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illustration of brain showing cerebellum

NIH grant supports research on locomotor dysfunction in Down Syndrome

illustration of brain showing cerebellum

The National Institutes of Health (NIH) has granted the Children’s National Research Institute (CNRI) nearly $500,000 to better understand and identify specific alterations in the circuitry of the cerebellum that results in locomotor dysfunction in down syndrome.

Down syndrome (DS), the most commonly diagnosed chromosomal condition, affects a range of behavioral domains in children including motor and cognitive function. Cerebellar pathology has been consistently observed in DS, and is thought to contribute to dysfunction in locomotor and adaptive motor skills. However, the specific neural pathways underlying locomotor learning that are disrupted in DS remain poorly understood.

The National Institutes of Health (NIH) has granted the Children’s National Research Institute (CNRI) nearly $500,000 through their NIH-wide initiative INCLUDE – INvestigating Co-occurring conditions across the Lifespan to Understand Down syndrome – to better understand and identify specific alterations in the circuitry of the cerebellum that results in locomotor dysfunction in DS. The INCLUDE initiative aims to support the most promising high risk-high reward basic science.

“There is still a lot unknown about Down syndrome, in particular how fundamental cellular and physiological mechanisms of neural circuit function are altered in this syndrome,” says Vittorio Gallo, Ph.D., chief research officer at Children’s National Hospital and scientific director of CNRI. “Grant funding is particularly important to have the resources to develop and apply new cutting-edge methodology to study this neurodevelopmental disorder.”

The main goal of this research is to identify specific alterations in the circuitry of the cerebellum that result in locomotor dysfunction in DS. Defining specific abnormalities in motor behavior, and identifying the brain regions and neurons which are functionally involved will provide the basis for developing potential therapies for treating motor problems in individuals with DS.

“The last decade has brought rapid advances in neurotechnology to address questions at the ‘systems-level’ understanding of brain function,” says Aaron Sathyanesan, Ph.D., a Children’s National postdoctoral research fellow. “This technology has rarely been applied to preclinical models of neurodevelopmental disorders, and even more rarely to models of Down syndrome.”

An example is the use of fiber-optics to probe changes in neural circuitry during behavior. Using this technology, researchers can now directly correlate the changes in circuitry to deficits in behavior.

“Along with the other approaches in our proposal, this represents the synthesis of a new experimental paradigm that we hope will push the field forward,” says Dr. Sathyanesan.

In 1960, the average life expectancy of a baby with Down syndrome was around 10 years. Today, that life expectancy has increased to more than 47 years. That significant increase reflects critical advances in medicine, however, kids with DS still live with long-term challenges in motor and cognitive ability.

Children’s National strongly supports translation and innovation, and recently recruited internationally renowned DS researcher, Tarik Haydar, Ph.D., as its new director of the Center for Neuroscience Research.

“We’re building significant strength in this area of research. This grant helps open new avenues of investigation to define which cells and circuits are impacted by this common neurodevelopmental disorder,” says Dr. Gallo. “Our cutting-edge approach will help us answer questions that we could not answer before.”

Nobuyuki Ishibashi

R01 grant funds white matter protection study for congenital heart disease

Nobuyuki Ishibashi

Nobuyuki Ishibashi, M.D., is the principal investigator on a $3.2 million NIH R01 to study white matter growth and repair in utero for fetal brains affected by congenital heart disease.

Many of the neurological deficits seen in children with congenital heart disease (CHD) are related to abnormal white matter development early in life caused by reduced oxygen supply to the brain while in utero. Children with immature white matter at birth also commonly sustain additional white matter injuries following cardiac surgery.

The NIH recently awarded a prestigious R01 grant totaling more than $3.2 million to a collaborative project led by the Center for Neuroscience Research, the Sheikh Zayed Institute for Pediatric Surgical Innovation and the Children’s National Heart Institute at Children’s National Hospital as well as MedStar Washington Hospital Center.

The research, titled “White matter protection in the fetus with congenital heart disease,” looks specifically at whether providing a supplemental amount of the naturally occurring tetrahydrobiopterin (BH4) for pregnant women could rescue white matter development of fetuses with congenital heart disease whose brains aren’t receiving enough oxygen – or suffering from hypoxic-ischemic events.

Previous preclinical studies have shown that this lack of oxygen depletes the brain’s natural BH4 level, and the researchers hypothesize that BH4 levels play a critical role in the growth and development of white matter in the fetal brain by triggering key cellular/molecular processes. Specifically, the study will focus on three aims:

  1. Establish in a preclinical model the optimal protective regiment for women pregnant with a fetus who has CHD to receive BH4.
  2. Determine the appropriate approach to deliver BH4 to this population
  3. Leverage genetic tools and biochemical techniques in the laboratory to better understand where and how BH4 levels play a role in the growth (or lack thereof) of oligodendrocytes—the primary cells of white matter.

This laboratory-based work is the first step to determining if the neurodevelopment of babies born with CHD can be preserved or recovered by addressing key brain development that occurs before the baby is even born. Findings related to congenital heart disease may also translate to other populations where white matter development is affected by hypoxia-ischemia, including premature infants.

The project is led by principal investigator Nobuyuki Ishibashi, M.D., with co-investigators Vittorio Gallo, Ph.D., Joseph Scafidi, D.O., and Mary Donofrio, M.D. as well as colleagues at MedStar Washington Hospital Center.

Vittorio Gallo and Mark Batshaw

Children’s National Research Institute releases annual report

Vittorio Gallo and Marc Batshaw

Children’s National Research Institute directors Vittorio Gallo, Ph.D., and Mark Batshaw, M.D.

The Children’s National Research Institute recently released its 2019-2020 academic annual report, titled 150 Years Stronger Through Discovery and Care to mark the hospital’s 150th birthday. Not only does the annual report give an overview of the institute’s research and education efforts, but it also gives a peek in to how the institute has mobilized to address the coronavirus pandemic.

“Our inaugural research program in 1947 began with a budget of less than $10,000 for the study of polio — a pressing health problem for Washington’s children at the time and a pandemic that many of us remember from our own childhoods,” says Vittorio Gallo, Ph.D., chief research officer at Children’s National Hospital and scientific director at Children’s National Research Institute. “Today, our research portfolio has grown to more than $75 million, and our 314 research faculty and their staff are dedicated to finding answers to many of the health challenges in childhood.”

Highlights from the Children’s National Research Institute annual report

  • In 2018, Children’s National began construction of its new Research & Innovation Campus (CNRIC) on 12 acres of land transferred by the U.S. Army as part of the decommissioning of the former Walter Reed Army Medical Center campus. In 2020, construction on the CNRIC will be complete, and in 2012, the Children’s National Research Institute will begin to transition to the campus.
  • In late 2019, a team of scientists led by Eric Vilain, M.D., Ph.D., director of the Center for Genetic Medicine Research, traveled to the Democratic Republic of Congo to collect samples from 60 individuals that will form the basis of a new reference genome data set. The researchers hope their project will generate better reference genome data for diverse populations, starting with those of Central African descent.
  • A gift of $5.7 million received by the Center for Translational Research’s director, Lisa Guay-Woodford, M.D., will reinforce close collaboration between research and clinical care to improve the care and treatment of children with polycystic kidney disease and other inherited renal disorders.
  • The Center for Neuroscience Research’s integration into the infrastructure of Children’s National Hospital has created a unique set of opportunities for scientists and clinicians to work together on pressing problems in children’s health.
  • Children’s National and the National Institute of Allergy and Infectious Diseases are tackling pediatric research across three main areas of mutual interest: primary immune deficiencies, food allergies and post-Lyme disease syndrome. Their shared goal is to conduct clinical and translational research that improves what we know about those conditions and how we care for children who have them.
  • An immunotherapy trial has allowed a little boy to be a kid again. In the two years since he received cellular immunotherapy, Matthew has shown no signs of a returning tumor — the longest span of time he’s been tumor-free since age 3.
  • In the past 6 years, the 104 device projects that came through the National Capital Consortium for Pediatric Device Innovation accelerator program raised $148,680,256 in follow-on funding.
  • Even though he’s watched more than 500 aspiring physicians pass through the Children’s National pediatric residency program, program director Dewesh Agrawal, M.D., still gets teary at every graduation.

Understanding and treating the novel coronavirus (COVID-19)

In a short period of time, Children’s National Research Institute has mobilized its scientists to address COVID-19, focusing on understanding the virus and advancing solutions to ameliorate the impact today and for future generations. Children’s National Research Institute Director Mark Batshaw, M.D., highlighted some of these efforts in the annual report:

  • Eric Vilain, M.D., Ph.D., director of the Center for Genetic Medicine Research, is looking at whether or not the microbiome of bacteria in the human nasal tract acts as a defensive shield against COVID-19.
  • Catherine Bollard, M.D., MBChB, director of the Center for Cancer and Immunology Research, and her team are seeing if they can “train” T cells to attack the invading coronavirus.
  • Sarah Mulkey, M.D., Ph.D., an investigator in the Center for Neuroscience Research and the Fetal Medicine Institute, is studying the effects of, and possible interventions for, coronavirus on the developing brain.

You can view the entire Children’s National Research Institute academic annual report online.

Vittorio Gallo

Special issue of “Neurochemical Research” honors Vittorio Gallo, Ph.D.

Vittorio Gallo

Investigators from around the world penned manuscripts that were assembled in a special issue of “Neurochemical Research” that honors Vittorio Gallo, Ph.D., for his leadership in the field of neural development and regeneration.

At a pivotal moment early in his career, Vittorio Gallo, Ph.D., was accepted to work with Professor Giulio Levi at the Institute for Cell Biology in Rome, a position that leveraged courses Gallo had taken in neurobiology and neurochemistry, and allowed him to work in the top research institute in Italy directed by the Nobel laureate, Professor Rita Levi-Montalcini.

For four years as a student and later as Levi’s collaborator, Gallo focused on amino acid neurotransmitters in the brain and mechanisms of glutamate and GABA release from nerve terminals. Those early years cemented a research focus on glutamate neurotransmission that would lead to a number of pivotal publications and research collaborations that have spanned decades.

Now, investigators from around the world who have worked most closely with Gallo penned tributes in the form of manuscripts that were assembled in a special issue of “Neurochemical Research” that honors Gallo “for his contributions to our understanding of glutamatergic and GABAergic transmission during brain development and to his leadership in the field of neural development and regeneration,” writes guest editor Arne Schousboe, of the University of Copenhagen in Denmark.

Dr. Gallo as a grad student

Vittorio Gallo, Ph.D. as a 21-year-old mustachioed graduate student.

“In spite of news headlines about competition in research and many of the negative things we hear about the research world, this shows that research is also able to create a community around us,” says Gallo, chief research officer at Children’s National Hospital and scientific director for the Children’s National Research Institute.

As just one example, he first met Schousboe 44 years ago when Gallo was a 21-year-old mustachioed graduate student.

“Research can really create a sense of community that we carry on from the time we are in training, nurture as we meet our colleagues at periodic conferences, and continue up to the present. Creating community is bi-directional: influencing people and being influenced by people. People were willing to contribute these 17 articles because they value me,” Gallo says. “This is a lot of work for the editor and the people who prepared papers for this special issue.”

In addition to Gallo publishing more than 140 peer-reviewed papers, 30 review articles and book chapters, Schousboe notes a number of Gallo’s accomplishments, including:

  • He helped to develop the cerebellar granule cell cultures as a model system to study how electrical activity and voltage-dependent calcium channels modulate granule neuron development and glutamate release.
  • He developed a biochemical/neuropharmacological assay to monitor the effects of GABA receptor modulators on the activity of GABA chloride channels in living neurons.
  • He and Maria Usowicz used patch-clamp recording and single channel analysis to demonstrate for the first time that astrocytes express glutamate-activated channels that display functional properties similar to neuronal counterparts.
  • He characterized one of the spliced isoforms of the AMPA receptor subunit gene Gria4 and demonstrated that this isoform was highly expressed in the cerebellum.
  • He and his Children’s National colleagues demonstrated that glutamate and GABA regulate oligodendrocyte progenitor cell proliferation and differentiation.
Purkinje cells

Purkinje cells are large neurons located in the cerebellum that are elaborately branched like interlocking tree limbs and represent the only source of output for the entire cerebellar cortex.

Even the image selected to grace the special issue’s cover continues the theme of continuity and leaving behind a legacy. That image of Purkinje cells was created by a young scientist who works in Gallo’s lab, Aaron Sathyanesan, Ph.D. Gallo began his career working on the cerebellum – a region of the brain important for motor control – and now studies with a team of scientists and clinician-scientists Purkinje cells’ role in locomotor adaptive behavior and how that is disrupted after neonatal brain injury.

“These cells are the main players in cerebellar circuitry,” Gallo says. “It’s a meaningful image because goes back to my roots as a graduate student and is also an image that someone produced in my lab early in his career. It’s very meaningful to me that Aaron agreed to provide this image for the cover of the special issue.”

Dr. Jonas and research collaborator Nobuyuki Ishibashi in the laboratory.

Cardiac surgery chief recognized for studies of surgery’s impacts on neurodevelopment

Dr. Jonas and research collaborator Nobuyuki Ishibashi in the laboratory.

Dr. Jonas and research collaborator Nobuyuki Ishibashi in the laboratory.

Richard Jonas, M.D., is this year’s recipient of the Newburger-Bellinger Cardiac Neurodevelopmental Award in recognition of his lifelong research into understanding the impact of cardiac surgery on the growth and development of the brain. The award was established in 2013 by the Cardiac Neurodevelopmental Outcome Collaborative (CNOC) to honor Jane Newburger and David Bellinger, pioneers in research designed to understand and improve neurodevelopmental outcomes for children with heart disease.

At Children’s National, Dr. Jonas’ laboratory studies of neuroprotection have been conducted in conjunction with Dr. Vittorio Gallo, director of neuroscience research at Children’s National, and Dr. Nobuyuki Ishibashi, director of the cardiac surgery research laboratory. Their NIH-supported studies have investigated the impact of congenital heart disease and cardiopulmonary bypass on the development of the brain, with particular focus on impacts to white matter, in people with congenital heart disease.

Dr. Jonas’s focus on neurodevelopment after cardiac surgery has spanned his entire career in medicine, starting with early studies in the Harvard psychology department where he developed models of ischemic brain injury. He subsequently undertook a series of highly productive pre-clinical cardiopulmonary bypass studies at the National Magnet Laboratory at MIT. These studies suggested that some of the bypass techniques used at the time were suboptimal. The findings helped spur a series of retrospective clinical studies and subsequently several prospective randomized clinical trials at Boston Children’s Hospital examining the neurodevelopmental consequences of various bypass techniques. These studies were conducted by Dr. Jonas and others, in collaboration with Dr. Jane Newburger and Dr. David Bellinger, for whom this award is named.

Dr. Jonas has been the chief of cardiac surgery and co-director of the Children’s National Heart Institute since 2004. He previously spent 20 years on staff at Children’s Hospital Boston including 10 years as department chief and as the William E. Ladd Chair of Surgery at Harvard Medical School.

As the recipient of the 2019 award, Dr. Jonas will deliver a keynote address at the 8th Annual Scientific Sessions of the Cardiac Neurodevelopmental Outcome Collaborative in Toronto, Ontario, October 11-13, 2019.

illustration of brain showing cerebellum

Focusing on the “little brain” to rescue cognition

illustration of brain showing cerebellum

Research faculty at Children’s National in Washington, D.C., with colleagues recently published a review article in Nature Reviews Neuroscience that covers the latest research about how abnormal development of the cerebellum leads to a variety of neurodevelopmental disorders.

Cerebellum translates as “little brain” in Latin. This piece of anatomy – that appears almost separate from the rest of the brain, tucked under the two cerebral hemispheres – long has been known to play a pivotal role in voluntary motor functions, such as walking or reaching for objects, as well as involuntary ones, such as maintaining posture.

But more recently, says Aaron Sathyanesan, Ph.D., a postdoctoral research fellow at the Children’s Research Institute, the research arm of Children’s National  in Washington, D.C., researchers have discovered that the cerebellum is also critically important for a variety of non-motor functions, including cognition and emotion.

Sathyanesan, who studies this brain region in the laboratory of Vittorio Gallo, Ph.D., Chief Research Officer at Children’s National and scientific director of the Children’s Research Institute, recently published a review article with colleagues in Nature Reviews Neuroscience covering the latest research about how altered development of the cerebellum contributes to a variety of neurodevelopmental disorders.

These disorders, he explains, are marked by problems in the nervous system that arise while it’s maturing, leading to effects on emotion, learning ability, self-control, or memory, or any combination of these. They include diagnoses as diverse as intellectual disability, autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder and Down syndrome.

“One reason why the cerebellum might be critically involved in each of these disorders,” Sathyanesan says, “is because its developmental trajectory takes so long.”

Unlike other brain structures, which have relatively short windows of development spanning weeks or months, the principal cells of the cerebellum – known as Purkinje cells – start to differentiate from stem cell precursors at the beginning of the seventh gestational week, with new cells continuing to appear until babies are nearly one year old.  In contrast, cells in the neocortex, a part of the brain involved in higher-order brain functions such as cognition, sensory perception and language is mostly finished forming while fetuses are still gestating in the womb.

This long window for maturation allows the cerebellum to make connections with other regions throughout the brain, such as extensive connections with the cerebral cortex, the outer layer of the cerebrum that plays a key role in perception, attention, awareness, thought, memory, language and consciousness. It also allows ample time for things to go wrong.

“Together,” Sathyanesan says, “these two characteristics are at the root of the cerebellum’s involvement in a host of neurodevelopmental disorders.”

For example, the review article notes, researchers have discovered both structural and functional abnormalities in the cerebellums of patients with ASD. Functional magnetic resonance imaging (MRI), an imaging technique that measures activity in different parts of the brain, suggests that significant differences exist between connectivity between the cerebellum and cortex in people with ASD compared with neurotypical individuals. Differences in cerebellar connectivity are also evident in resting-state functional connectivity MRI, an imaging technique that measures brain activity in subjects when they are not performing a specific task. Some of these differences appear to involve patterns of overconnectivity to different brain regions, explains Sathyanesan; other differences suggest that the cerebellums of patients with ASD don’t have enough connections to other brain regions.

These findings could clarify research from Children’s National and elsewhere that has shown that babies born prematurely often sustain cerebellar injuries due to multiple hits, including a lack of oxygen supplied by infants’ immature lungs, he adds. Besides having a sibling with ASD, premature birth is the most prevalent risk factor for an ASD diagnosis.

The review also notes that researchers have discovered structural changes in the cerebellums of patients with Down syndrome, who tend to have smaller cerebellar volumes than neurotypical individuals. Experimental models of this trisomy recapitulate this difference, along with abnormal connectivity to the cerebral cortex and other brain regions.

Although the cerebellum is a pivotal contributor toward these conditions, Sathyanesan says, learning more about this brain region helps make it an important target for treating these neurodevelopmental disorders. For example, he says, researchers are investigating whether problems with the cerebellum and abnormal connectivity could be lessened through a non-invasive form of brain stimulation called transcranial direct current stimulation or an invasive one known as deep brain stimulation. Similarly, a variety of existing pharmaceuticals or new ones in development could modify the cerebellum’s biochemistry and, consequently, its function.

“If we can rescue the cerebellum’s normal activity in these disorders, we may be able to alleviate the problems with cognition that pervade them all,” he says.

In addition to Sathyanesan and Senior Author Gallo, Children’s National study co-authors include Joseph Scafidi, D.O., neonatal neurologist; Joy Zhou and Roy V. Sillitoe, Baylor College of Medicine; and Detlef H. Heck, of University of Tennessee Health Science Center.

Financial support for research described in this post was provided by the National Institute of Neurological Disorders and Stroke under grant numbers 5R01NS099461, R01NS089664, R01NS100874, R01NS105138 and R37NS109478; the Hamill Foundation; the Baylor College of Medicine Intellectual and Developmental Disabilities Research Center under grant number U54HD083092; the University of Tennessee Health Science Center (UTHSC) Neuroscience Institute; the UTHSC Cornet Award; the National Institute of Mental Health under grant number R01MH112143; and the District of Columbia Intellectual and Developmental Disabilities Research Center under grant number U54 HD090257.

Vittorio Gallo Alpha Omega Alpha Award

Vittorio Gallo, Ph.D., inducted into Alpha Omega Alpha

Vittorio Gallo Alpha Omega Alpha Award

Vittorio Gallo, Ph.D., Chief Research Officer at Children’s National, was inducted into Alpha Omega Alpha (AΩA), a national medical honor society that since 1902 has recognized excellence, leadership and research in the medical profession.

“I think it’s great to receive this recognition. I was very excited and surprised,” Gallo says of being nominated to join the honor society.

“Traditionally AΩA membership is based on professionalism, academic and clinical excellence, research, and community service – all in the name of ‘being worthy to serve the suffering,’ which is what the Greek letters AΩA stand for,” says Panagiotis Kratimenos, M.D., Ph.D., an ΑΩΑ member and attending neonatologist at Children’s National who conducts neuroscience research under Gallo’s mentorship. Dr. Kratimenos nominated his mentor for induction.

“Being his mentee, I thought Gallo was an excellent choice for AΩΑ faculty member,” Dr. Kratimenos says. “He is an outstanding scientist, an excellent mentor and his research is focused on improving the quality of life of children with brain injury and developmental disabilities – so he serves the suffering. He also has mentored numerous physicians over the course of his career.”

Gallo’s formal induction occurred in late May 2019, just prior to the medical school graduation at the George Washington University School of Medicine & Health Sciences (GWSMHS) and was strongly supported by Jeffrey S. Akman, Vice President for Health Affairs and Dean of the university’s medical school.

“I’ve been part of Children’s National and in the medical field for almost 18 years. That’s what I’m passionate about: being able to enhance translational research in a clinical environment,” Gallo says. “In a way, this recognition from the medical field is a perfect match for what I do. As Chief Research Officer at Children’s National, I am charged with continuing to expand our research program in one of the top U.S. children’s hospitals. And, as Associate Dean for Child Health Research at GWSMHS, I enhance research collaboration between the two institutions.”

Vittorio Gallo

Neurodevelopmental disorders: Developing medical treatments

Vittorio Gallo

Vittorio Gallo, Ph.D., Chief Research Officer, participates in the world’s largest general scientific gathering, leading panelists in a timely conversation about progress made so far with neurodevelopmental disorders and challenges that lie ahead.

The human brain is the body’s operating system. Imagine if rogue code worked its way into its hardware and software, delaying some processes, disrupting others, wreaking general havoc.

Neurodevelopmental disorders are like that errant code. They can occur early in life and impact brain development for the rest of the person’s life. Not only can fundamental brain development go awry, processes that refine the brain also can become abnormal, creating a double neural hit.  Adding to those complications, children with neurodevelopmental disorders like autism spectrum disorder (ASD) and Fragile X syndrome often contend with multiple, overlapping cognitive impairments and learning disabilities.

The multiple layers of complexities for these disorders can make developing effective medical treatments particularly challenging, says Vittorio Gallo, Ph.D., Chief Research Officer at Children’s National Health System and recipient of a coveted Senator Jacob Javits Award in the Neurosciences.

During the Feb. 16, 2019, “Neurodevelopmental Disorders: Developing Medical Treatments” symposium, Gallo will guide esteemed panelists in a timely conversation about progress made so far and challenges that lie ahead during the AAAS Annual Meeting in Washington, the world’s largest general scientific gathering.

“This is a very important symposium; we’re going to put all of the open questions on the table,” says Gallo. “We’re going to present a snapshot of where the field is right now: We’ve made incredible advances in developmental neuroscience, neonatology, neurology, diagnostic imaging and other related fields. The essential building blocks are in place. Where are we now in developing therapeutics for these complex disorders?”

For select disorders, many genes have been identified, and each new gene has the potential to become a target for improved therapies. However, for other neurodevelopmental disorders, like ASD, an array of new genes continue to be discovered, leaving an unfinished picture of which genetic networks are of most importance.

Gallo says the assembled experts also plan to explore major research questions that remain unanswered as well as how to learn from past experiences to make future studies more powerful and insightful.

“One topic up for discussion will be new preclinical models that have the potential to help in identifying specific mechanisms that cause these disorders. A combination of genetic, biological, psychosocial and environmental risk factors are being combined in these preclinical models,” Gallo says.

“Our studies of the future need to move beyond describing and observing in order to transform into studies that establish causality between the aberrant developmental processes and these constellations of neurodevelopmental disorders.”

Study authors Aaron Sathyanesan, Ph.D., Joseph Abbah, B.Pharm., Ph.D., Srikanya Kundu, Ph.D. and Vittorio Gallo, Ph.D.

Children’s perinatal hypoxia research lauded

Study authors Aaron Sathyanesan, Ph.D., Joseph Abbah, B.Pharm., Ph.D., Srikanya Kundu, Ph.D. and Vittorio Gallo, Ph.D.

Study authors Aaron Sathyanesan, Ph.D., Joseph Abbah, B.Pharm., Ph.D., Srikanya Kundu, Ph.D. and Vittorio Gallo, Ph.D.

Chronic sublethal hypoxia is associated with locomotor miscoordination and long-term cerebellar learning deficits in a clinically relevant model of neonatal brain injury, according to a study led by Children’s National Health System researchers published by Nature Communications. Using high-tech optical and physiological methods that allow researchers to turn neurons on and off and an advanced behavioral tool, the research team found that Purkinje cells fire significantly less often after injury due to perinatal hypoxia.

The research team leveraged a fully automated, computerized apparatus – an Erasmus Ladder – to test experimental models’ adaptive cerebellar locomotor learning skills, tracking their missteps as well as how long it took the models to learn the course.

The research project, led by Aaron Sathyanesan, Ph.D., a Children’s postdoctoral research fellow, was honored with a F1000 primevery good rating.” The Children’s research team used both quantitative behavior tests and electrophysiological assays, “a valuable and objective platform for functional assessment of targeted therapeutics in neurological disorders,” according to the recommendation on a digital forum in which the world’s leading scientists and clinicians highlight the best articles published in the field.

Calling the Erasmus Ladder an “elegant” behavioral system, Richard Lu, Ph.D., and Kalen Berry write that the Children’s National Health System research team “revealed locomotor behavior and cerebellar learning deficits, and further utilized multielectrode recording/optogenetics approaches to define critical pathophysiological features, such as defects in Purkinje cell firing after neonatal brain injury.”

Lu, Beatrice C. Lampkin Endowed Chair in Cancer Epigenetics, and Berry, an associate faculty member in the Cancer and Blood Diseases Institute, both at Cincinnati Children’s, note that the Children’s results “suggest that GABA signaling may represent a potential therapeutic target for hypoxia-related neonatal brain injury that, if provided at the correct time during development post-injury, could offer lifelong improvements.”

In addition to Sathyanesan, Children’s co-authors include Co-Lead Author, Srikanya Kundu, Ph.D., and Joseph Abbah, both of Children’s Center for Neuroscience Research, and Vittorio Gallo, Ph.D., Children’s Chief Research Officer and the study’s senior author.

Research covered in this story was supported by the Intellectual and Developmental Disability Research Center under award number U54HD090257.

Nobuyuki Ishibashi

Cortical dysmaturation in congenital heart disease

Nobuyuki Ishibashi

On Jan. 4, 2019, Nobuyuki Ishibashi, M.D., the director of the Cardiac Surgery Research Laboratory and an investigator with the Center for Neuroscience Research at Children’s National Health System, published a review in Trends in Neurosciences about the mechanisms of cortical dysmaturation, or disturbances in cortical development, that can occur in children born with congenital heart disease (CHD). By understanding the early-life impact and relationship between cardiac abnormalities and cortical neuronal development, Dr. Ishibashi and the study authors hope to influence strategies for neonatal neuroprotection, mitigating the risk for developmental delays among CHD patients.

Dr. Ishibashi answers questions about this review and CHD-neurodevelopmental research:

  1. Tell us more about your research. Why did you choose to study these interactions in this patient population?

My research focuses on studying how CHD and neonatal cardiac surgery affect the rapidly-developing brain. Many children with CHD, particularly the most complex anomalies, suffer from important behavioral anomalies and neurodevelopmental delays after cardiac surgery. As a surgeon scientist, I want to optimize treatment strategy and develop a new standard of care that will reduce neurodevelopmental impairment in our patients.

  1. How does this study fit into your larger body of work? What are a few take-home messages from this paper?

Our team and other laboratories have recently identified a persistent perinatal neurogenesis that targets the frontal cortex – the brain area responsible for higher-order cognitive functions. The main message from this article is that further understanding of the cellular and molecular mechanisms underlying cortical development and dysmaturation will likely help to identify novel strategies to treat and improve outcomes in our patients suffering from intellectual and behavioral disabilities.

  1. What do you want pediatricians and researchers to know about this study? Why is it important right now?

Although the hospital mortality risk is greatly reduced, children with complex CHD frequently display subsequent neurological disabilities affecting intellectual function, memory, executive function, speech and language, gross and fine motor skills and visuospatial functions. In addition to the impact of the neurological morbidity on the patients themselves, the toll on families and society is immense. Therefore it is crucial to determine the causes of altered brain maturation in CHD.

  1. How do you envision this research influencing future studies and pediatric health outcomes? As a researcher, how will you proceed?

In this article we placed special emphasis on the need for well-designed preclinical studies to define disturbances in cortical neurogenesis due to perinatal brain injury. I believe that further study of the impact of hypoxemia on brain development is of broad relevance — not just for children with congenital heart disease, but for other populations where intellectual and behavioral dysfunctions are a source of chronic morbidity, such as survivors of premature birth.

  1. What discoveries do you envision being at the forefront of this field?

One of the important questions is: During which developmental period, prenatal or postnatal, is the brain most sensitive to developmental and behavioral disabilities associated with hypoxemia? Future experimental models will help us study key effects of congenital cortical development anomalies on brain development in children with CHD.

  1. What impact could this research make? What’s the most striking finding and how do you think it will influence the field?

Although cortical neurogenesis at fetal and adult stages has been widely studied, the development of the human frontal cortex during the perinatal period has only recently received greater attention as a result of new identification of ongoing postnatal neurogenesis in the region responsible for important intellectual and behavioral functions. Children’s National is very excited with the discoveries because it has opened new opportunities that may lead to regeneration and repair of the dysmature cortex. If researchers identify ways to restore endogenous neurogenic abilities after birth, the risk of neurodevelopment disabilities and limitations could be greatly reduced.

  1. Is there anything else you would like to add that we didn’t ask you about? What excites you about this research?

In this article we highlight an urgent need to create a truly translational area of research in CHD-induced brain injury through further exploration and integration of preclinical models. I’m very excited about the highly productive partnerships we developed within the Center for Neuroscience Research at Children’s National, led by an internationally-renowned developmental neuroscientist, Vittorio Gallo, Ph.D., who is a co-senior author of this article. Because of our collaboration, my team has successfully utilized sophisticated and cutting-edge neuroscience techniques to study brain development in children born with CHD. To determine the causes of altered brain maturation in congenital heart disease and ultimately improve neurological function, we believe that a strong unity between cardiovascular and neuroscience research must be established.

Additional study authors include Camille Leonetti, Ph.D., a postdoctoral research fellow with the Center for Neuroscience Research and Children’s National Heart Institute, and Stephen Back, M.D., Ph.D., a professor of pediatrics at Oregon Health and Science University.

The research was supported by multiple grants and awards from the National Institutes of Health, inclusive of the National Heart Lung and Blood Institute (RO1HL139712), the National Institute of Neurological Disorders and Stroke (1RO1NS054044, R37NS045737, R37NS109478), the National Institute on Aging (1RO1AG031892-01) and the National Institute of Child Health and Human Development (U54HD090257).

Additional support for this review was awarded by the American Heart Association (17GRNT33370058) and the District of Columbia Intellectual and Developmental Disabilities Research Center, which is supported through the Eunice Kennedy Shriver National Institute of Child Health and Human Development program grant 1U54HD090257.

Vittorio Gallo

Vittorio Gallo, Ph.D., honored with Senator Jacob Javits Award in the Neurosciences

Vittorio Gallo

Vittorio Gallo, Ph.D., Children’s Chief Research Officer, has been awarded a prestigious Senator Jacob Javits Award in the Neurosciences, which extends federal funding for Gallo’s lab for at least seven years. The long-term support is offered to “investigators with a history of exceptional talent, imagination and preeminent scientific achievement.”

Only National Institute of Neurological Disorders and Stroke (NINDS) staff members or NINDS Council members may nominate researchers for the coveted awards, named in honor of Sen. Jacob Javits, (R-New York). Before his death, Sen. Javits advocated for additional research in a wide variety of disorders of the brain and nervous system.

“It’s a great recognition from the neuroscience community and from NINDS for contributions to neuroscience and outstanding service to the neuroscience community,” Gallo says. “It’s also very exciting because it gives additional national visibility to our Center for Neuroscience Research and to Children’s National Health System, as one of the nation’s leading research institutions.”

Through the award, Gallo’s successful five-year Research Project Grant from the National Institutes of Health will be converted to a seven-year award. In the fourth year of federal funding, he can apply for a budgetary increase.

“Thanks to this funding, I predict we will be able to identify cellular and molecular mechanisms that underlie developmental delays in children who experienced neonatal brain injury,” Gallo says.

“We are really starting to understand this very complex problem: How does neonatal brain injury lead to developmental delays later in a child’s life? What are the mechanisms? We know there are cognitive and behavioral abnormalities that are common to children who have experienced hypoxia as newborns. But we don’t really know how these behavioral abnormalities arise at the physiological, cellular and molecular levels.”

Gallo says identifying these cellular targets will make it possible to tailor interventions that target distinct cell types at different times in the child’s life.

Recent work by Gallo’s lab includes a research paper published online Aug. 13, 2018, by Nature Communications that found chronic sublethal hypoxia is associated with locomotor miscoordination and long-term cerebellar learning deficits in a clinically relevant model of neonatal brain injury.

toddler on a playground

Perinatal hypoxia associated with long-term cerebellar learning deficits and Purkinje cell misfiring

toddler on a playground

The type of hypoxia that occurs with preterm birth is associated with locomotor miscoordination and long-term cerebellar learning deficits but can be partially alleviated with an off-the-shelf medicine, according to a study using a preclinical model.

Oxygen deprivation associated with preterm birth leaves telltale signs on the brains of newborns in the form of alterations to cerebellar white matter at the cellular and the physiological levels. Now, an experimental model of this chronic hypoxia reveals that those cellular alterations have behavioral consequences.

Chronic sublethal hypoxia is associated with locomotor miscoordination and long-term cerebellar learning deficits in a clinically relevant model of neonatal brain injury, according to a study led by Children’s National Health System researchers published online Aug. 13, 2018, by Nature Communications. Using high-tech optical and physiological methods that allow researchers to turn neurons on and off and an advanced behavioral tool, the research team finds that Purkinje cells fire significantly less often after injury due to perinatal hypoxia. However, an off-the-shelf medicine now used to treat epilepsy enables those specialized brain cells to regain their ability to fire, improving locomotor performance.

Step out of the car onto the pavement, hop up to the level of the curb, stride to the entrance, and climb a flight of stairs. Or, play a round of tennis. The cerebellum coordinates such locomotor performance and muscle memory, guiding people of all ages as they adapt to a changing environment.

“Most of us successfully coordinate our movements to navigate the three-dimensional spaces we encounter daily,” says Vittorio Gallo, Ph.D., Children’s Chief Research Officer and the study’s senior author. “After children start walking, they also have to learn how to navigate the environment and the spaces around them.”

These essential tasks, Gallo says, are coordinated by Purkinje cells, large neurons located in the cerebellum that are elaborately branched like interlocking tree limbs and represent the only source of output for the entire cerebellar cortex. The rate of development of the fetal cerebellum dramatically increases at a time during pregnancy that often coincides with preterm birth, which can delay or disrupt normal brain development.

“It’s almost like a short circuit. Purkinje cells play a very crucial role, and when the frequency of their firing is diminished by injury the whole output of this brain region is impaired,” Gallo says. “For a family of a child who has this type of impaired neural development, if we understand the nature of this disrupted circuitry and can better quantify it, in terms of locomotor performance, then we can develop new therapeutic approaches.”

Study authors Aaron Sathyanesan, Ph.D., Joseph Abbah, B.Pharm., Ph.D., Srikanya Kundu, Ph.D. and Vittorio Gallo, Ph.D.

The research team leveraged a fully automated, computerized apparatus that looks like a ladder placed on a flat surface, encased in glass, with a darkened box at either end. Both the hypoxic and control groups had training sessions during which they learned how to traverse the horizontal ladder, coaxed out of the darkened room by a gentle puff of air and a light cue. Challenge sessions tested their adaptive cerebellar locomotor learning skills. The pads they strode across were pressure-sensitive and analyzed individual stepping patterns to predict how long it should take each to complete the course.

During challenge sessions, obstacles were presented in the course, announced by an audible tone. If learning was normal, then the response to the tone paired with the obstacle would be a quick adjustment of movement, without breaking stride, says Aaron Sathyanesan, Ph.D., co-lead author. Experimental models exposed to perinatal hypoxia showed significant deficits in associating that tone with the obstacle.

“With the control group, we saw fewer missteps during any given trial,” Sathyanesan says. “And, when they got really comfortable, they took longer steps. With the hypoxic group, it took them longer to learn the course. They made a significantly higher number of missteps from day one. By the end of the training period, they could walk along all of the default rungs, but it took them longer to learn how to do so.”

Purkinje cells fire two different kinds of spikes. Simple spikes are a form of constant activity as rhythmic and automatic as a heartbeat. Complex spikes, by contrast, occur less frequently. Sathyanesan and co-authors say that some of the deficits that they observed were due to a reduction in the frequency of simple spiking.

Two weeks after experiencing hypoxia, the hypoxic group’s locomotor performance remained significantly worse than the control group, and delays in learning could still be seen five weeks after hypoxia.

Gamma-aminobutyric acid (GABA), a neurotransmitter, excites immature neurons before and shortly after birth but soon afterward switches to having an inhibitory effect within in the cerebellum, Sathyanesan says. The research team hypothesizes that reduced levels of excitatory GABA during early development leads to long-term motor problems. Using an off-the-shelf drug to increase GABA levels immediately after hypoxia dramatically improved locomotor performance.

“Treating experimental models with tiagabine after hypoxic injury elevates GABA levels, partially restoring Purkinje cells’ ability to fire,” Gallo says. “We now know that restoring GABA levels during this specific window of time has a beneficial effect. However, our approach was not specifically targeted to Purkinje cells. We elevated GABA everywhere in the brain. With more targeted and selective administration to Purkinje cells, we want to gauge whether tiagabine has a more powerful effect on normalizing firing frequency.”

In addition to Gallo and Sathyanesan, Children’s co-authors include Co-Lead Author, Srikanya Kundu, Ph.D., and Joseph Abbah, B.Pharm., Ph.D., both of Children’s Center for Neuroscience Research.

Research covered in this story was supported by the Intellectual and Developmental Disability Research Center under award number U54HD090257.

Research and Education Week awardees embody the diverse power of innovation

cnmc-research-education-week

“Diversity powers innovation” was brought to life at Children’s National April 16 to 20, 2018, during the eighth annual Research and Education Week. Children’s faculty were honored as President’s Award winners and for exhibiting outstanding mentorship, while more than 360 scientific poster presentations were displayed throughout the Main Atrium.

Two clinical researchers received Mentorship Awards for excellence in fostering the development of junior faculty. Lauren Kenworthy, Ph.D received the award for Translational Science and Murray M. Pollack, M.D., M.B.A., was recognized in the Clinical Science category as part of Children’s National Health System’s Research and Education Week 2018.

Dr. Kenworthy has devoted her career to improving the lives of people on the autism spectrum and was cited by former mentees as an inspirational and tireless counselor. Her mentorship led to promising new lines of research investigating methods for engaging culturally diverse families in autism studies, as well as the impact of dual language exposure on cognition in autism.

Meanwhile, Dr. Pollack was honored for his enduring focus on motivating early-career professionals to investigate outcomes in pediatric critical care, emergency medicine and neonatology. Dr. Pollack is one of the founders of the Collaborative Pediatric Critical Care Research Network. He developed PRISM 1 and 2, which has revolutionized pediatric intensive care by providing a methodology to predict mortality and outcome using standardly collected clinical data. Mentees credit Dr. Pollack with helping them develop critical thinking skills and encouraging them to address creativity and focus in their research agenda.

In addition to the Mentorship and President’s Awards, 34 other Children’s National faculty, residents, interns and research staff were among the winners of Poster Presentation awards. The event is a celebration of the commitment to improving pediatric health in the form of education, research, scholarship and innovation that occurs every day at Children’s National.

Children’s Research Institute (CRI) served as host for the week’s events to showcase the breadth of research and education programs occurring within the entire health system, along with the rich demographic and cultural origins of the teams that make up Children’s National. The lineup of events included scientific poster presentations, as well as a full slate of guest lectures, educational workshops and panel discussions.

“It’s critical that we provide pathways for young people of all backgrounds to pursue careers in science and medicine,” says Vittorio Gallo, Ph.D., Children’s chief research officer and CRI’s scientific director. “In an accelerated global research and health care environment, internationalization of innovation requires an understanding of cultural diversity and inclusion of different mindsets and broader spectrums of perspectives and expertise from a wide range of networks,” Gallo adds.

“Here at Children’s National we want our current and future clinician-researchers to reflect the patients we serve, which is why our emphasis this year was on harnessing diversity and inclusion as tools to power innovation,” says Mark L. Batshaw, M.D., physician-in-chief and chief academic officer of Children’s National.

“Research and Education Week 2018 presented a perfect opportunity to celebrate the work of our diverse research, education and care teams, who have come together to find innovative solutions by working with local, national and international partners. This event highlights the ingenuity and inspiration that our researchers contribute to our mission of healing children,” Dr. Batshaw concludes.

Awards for the best posters were distributed according to the following categories:

  • Basic and translational science
  • Quality and performance improvement
  • Clinical research
  • Community-based research and
  • Education, training and program development.

Each winner illustrated promising advances in the development of new therapies, diagnostics and medical devices.

Diversity powers innovation: Denice Cora-Bramble, M.D., MBA
Diversity powers innovation: Vittorio Gallo, Ph.D.
Diversity powers innovation: Mark L. Batshaw, M.D.

Vittorio Gallo

Perinatal brain injury headlines American Society for Neurochemistry

Vittorio Gallo

Dr. Gallo’s research could have major implications for overcoming the common behavioral and developmental challenges associated with premature birth.

Children’s National Chief Research Officer Vittorio Gallo, Ph.D., recently had the honor of presenting a presidential lecture at the 48th Annual Meeting of the American Society for Neurochemistry (ASN). The lecture focused on his lifelong investigations of the cellular and molecular mechanisms of white matter development and injury, including myelin and glial cells – which are involved in the brain’s response to injury.

Specifically, he outlined the underlying diffuse white matter injury observed in his lab’s pre-clinical model of perinatal hypoxia, and presented new, non-invasive interventions that promote functional recovery and attenuate developmental delay after perinatal injury in the model. Diffuse white matter injuries are the most frequently observed pattern of brain injury in contemporary cohorts of premature infants. Illuminating methods that might stimulate growth and repair of such injuries shows promise for potential noninvasive strategies that might mitigate the long-term behavioral abnormalities and developmental delay associated with premature birth.

Dr. Gallo’s work in developmental neuroscience has been seminal in deepening understanding of cerebral palsy and multiple sclerosis. During his tenure as center director, he transformed the Center for Neuroscience Research into one of the nation’s premier programs.

ASN gathers nearly 400 delegates from the neurochemistry sector each year, including bench and clinical scientists, principal investigators, graduate students and postdoctoral fellows all actively involved in research from North America and around the world.

Vittorio Gallo

How the environment helps to shape the brain

Vittorio Gallo

“The strength, duration and timing of environmental experience influences plasticity in brain circuitry, which is made up of communication cables called axons that link neurons throughout the brain and are coated by myelin, a fatty substance that helps nerve impulses speed from place to place,” says Vittorio Gallo, Ph.D., Chief Research Officer at Children’s National and senior study author.

Researchers have long known that babies of all kinds need to be exposed to rich, complex environments for optimal brain health and potential. Exposure to new sights, sounds and other sensory experiences appears to be critical for strengthening infants’ developing brains and encouraging smoothly running neural networks. Until recently, little was known about the biological mechanisms behind this phenomenon.

In a review article published online Aug. 22, 2017 in Trends in Neurosciences, Children’s National Health System researchers discuss the role of environmental stimuli on the development of myelin—the fatty insulation that surrounds the extensions that connect cells throughout the nervous system and make up a large part of the brain’s white matter. Positive influences, such as exposure to a large vocabulary and novel objects, can boost the growth of myelin. Conversely, negative influences, such as neglect and social isolation, can harm it, potentially altering the course of brain development.

“The strength, duration and timing of environmental experience influences plasticity in brain circuitry, which is made up of communication cables called axons that link neurons throughout the brain and are coated by myelin, a fatty substance that helps nerve impulses speed from place to place,” says Vittorio Gallo, Ph.D., Chief Research Officer at Children’s National and senior study author. “As it responds to environmental stimuli, the brain continually shores up myelin’s integrity. Just as important, damaged myelin can leave gaps in the neural network which can lead to cognitive, motor and behavioral deficits.”

According to Gallo and study lead author Thomas A. Forbes, a pool of oligodendrocyte progenitor cells (OPCs) specialize in making myelin and do so from childhood into adulthood. The resulting oligodendrocyte cells (OLs) form an important working partnership with axons. From approximately 23 to 37 weeks’ gestation, OLs develop in the fetal brain and they continue to be generated after birth until adolescence.

“This dynamic feedback loop between myelin plasticity and neuronal excitability is crucial,” Forbes says. “It helps to strengthen motor and cognitive function and permits children and adults to learn new skills and to record new memories.”

In utero, genetics plays an outsized role in the initial structure of white matter, which is located in the subcortical region of the brain and takes its white color from myelin, the lipid and protein sheath that electrically insulates nerve cells. Defects in the microstructural organization of white matter are associated with many neurodevelopmental disorders. Once infants are born, environmental experiences also can begin to exert a meaningful role.

“The environment can be viewed as a noninvasive therapeutic approach that can be employed to bolster white matter health, either on its own or working in tandem with pharmacologic therapies,” Gallo adds. “The question is how to design the best environment for infants and children to grow and to achieve the highest cognitive function. An enriched environment not only involves the opportunity to move and participate in physical exercise and physical therapy; it is also an environment where there is novelty, new experiences and continuously active learning. It is equally important to minimize social stressors. It’s all about the balance.”

Among the potential interventions to boost brain power, independent of socioeconomic status:

  • Exposing children to new and different objects with an opportunity for physical activity and interaction with a number of playmates. This type of setting challenges the child to continuously adapt to his or her surroundings in a social, physical and experiential manner. In experimental models, enriched environments supported brain health by increasing the volume and length of myelinated fibers, the volume of myelin sheaths and by boosting total brain volume.
  • Exposure to music helps with cognition, hearing and motor skills for those who play an instrument, tapping multiple areas of the brain to work together collaboratively. Diffusion tensor imaging (DTI) reveals that professional pianists who began playing as children have improved white matter integrity and plasticity, Gallo and Forbes
  • At its heart, active learning requires interacting with and adapting to the environment. Generating new OLs influences learning new motor skills in the very young as well as the very old. And cognitive training and stimulation shapes and preserves white matter integrity in the aging.
  • DTI studies indicate that four weeks of integrative mind-body training alters myelination and improves white matter efficiency with especially pronounced changes in the area of the brain responsible for self-regulation, impulse control and emotion.
  • Voluntary exercise in experimental models is associated with OPCs differentiating into mature OLs. Imaging studies show a positive relationship between physical fitness, white matter health and the brain networks involved in memory.

Conversely, such negative influences as premature birth, poor nutrition, disease, neglect and social isolation can degrade myelin integrity, compromising the person’s ability to carry out basic motor skills and cognitive function. Usually, the pool of OPCs expands as the fetus is about to be born. But brain injury, lack of oxygen and restricted blood supply can delay maturation of certain brain cells and can cause abnormalities in white matter that diminish the brain’s capacity to synthesize myelin. Additional white matter insults can be caused by use of anesthesia and stress, among other variables.

The environmental influence has the potential to be “the Archimedes’ Lever to appropriating WM development among a limited range of only partially efficacious treatment options,” the authors conclude.

A sirtuin might help repair a common neonatal brain injury

Sirtuin could repair common neonatal brain injury

A sirtuin might help repair a common neonatal brain injury

A team of researchers  investigated the molecular mechanisms behind oligodendrocyte progenitor cell proliferation in neonatal hypoxia.

What’s known

Hypoxia, or a lack of oxygen, is a major cause of diffuse white matter injury (DWMI). This condition leads to permanent developmental disabilities in prematurely born infants. The long-term abnormalities of the brain’s white matter that characterize DWMI are caused by the loss of a specific type of cells known as oligodendrocytes, which support nerve cells and produce myelin, a lipid and protein sheath that electrically insulates nerve cells. Oligodendrocytes are produced by a population of immature cells known as oligodendrocyte progenitor cells (OPCs). Previous research has shown that hypoxia can trigger OPCs to proliferate and presumably produce new oligodendrocytes. The molecular pathways that hypoxia triggers to make new OPCs remain unclear.

What’s new

A team of researchers led by Vittorio Gallo, Ph.D., director of the Center for Neuroscience Research and the Intellectual and Developmental Disabilities Research Center at Children’s National Health System, investigated the molecular mechanisms behind what prompts OPCs to proliferate in a preclinical model of neonatal hypoxia. The researchers found that a molecule known as Sirt1 acts as a major regulator of OPC proliferation and regeneration. Sirt1 is a sirtuin, a class of molecules that has attracted interest over the past several years for its role in stem cells, aging and inflammation. Hypoxia appears to induce Sirt1 formation. When the researchers prevented brain tissues in petri dishes from making Sirt1 or removed this molecule in preclinical models, these actions prevented OPC proliferation. What’s more, preventing Sirt1 production also inhibited OPCs from making oligodendrocytes. These findings suggest that Sirt1 is essential for replacing oligodendrocytes to repair DWMI after hypoxia. Additionally, finding ways to enhance Sirt1 activity eventually could provide a novel way to help infants recover after hypoxia and prevent DWMI.

Questions for future research

Q: How can Sirt1 activity be enhanced in preclinical models and humans?
Q: Can deficits triggered by diffuse white matter injury be prevented or reversed with Sirt1?
Q: Which other treatments might be useful for diffuse white matter injury?

Source: Sirt1 regulates glial progenitor proliferation and regeneration in white matter after neonatal brain injury.” Jablonska, M., M. Gierdalski, L. Chew, T. Hawley, M. Catron, A. Lichauco, J. Cabrera-Luque, T. Yuen, D. Rowitch and V. Gallo. Published by Nature Communications on Dec. 19, 2016.

Congenital heart disease and cortical growth

The cover of  Science Translational Medicine features a new study of the cellular-level changes in the brain induced by congenital heart disease. Reprinted with permission from AAAS. Not for download

Disruptions in cerebral oxygen supply caused by congenital heart disease have significant impact on cortical growth, according to a research led by Children’s National Health System. The findings of the research team, which include co-authors from the National Institutes of Health, Boston Children’s Hospital and Johns Hopkins School of Medicine, appear on the cover of Science Translational Medicine. The subventricular zone (SVZ) in normal newborns’ brains is home to the largest stockpile of neural stem/progenitor cells, with newly generated neurons migrating from this zone to specific regions of the frontal cortex and differentiating into interneurons. When newborns experience disruptions in cerebral oxygen supply due to congenital heart disease, essential cellular processes go awry and this contributes to reduced cortical growth.

The preliminary findings point to the importance of restoring these cells’ neurogenic potential, possibly through therapeutics, to lessen children’s long-­term neurological deficits.

“We know that congenital heart disease (CHD) reduces cerebral oxygen at a time when the developing fetal brain most needs oxygen. Now, we are beginning to understand the mechanisms of CHD-­induced brain injuries at a cellular level, and we have identified a robust supply of cells that have the ability to travel directly to the site of injury and potentially provide help by replacing lost or damaged neurons,” says Nobuyuki Ishibashi, M.D., Director of the Cardiac Surgery Research Laboratory at Children’s National, and co­-senior study author.

The third trimester of pregnancy is a time of dramatic growth for the fetal brain, which expands in volume and develops complex structures and network connections that growing children rely on throughout adulthood. According to the National Heart, Lung, and Blood Institute, congenital heart defects are the most common major birth defect, affecting 8 in 1,000 newborns. Infants born with CHD can experience myriad neurological deficits, including behavioral, cognitive, social, motor and attention disorders, the research team adds.

Cardiologists have tapped non­invasive imaging to monitor fetal hearts during gestation in high-­risk pregnancies and can then perform corrective surgery in the first weeks of life to fix damaged hearts. Long­ term neurological deficits due to immature cortical development also have emerged as major challenges in pregnancies complicated by CHD.

“I think this is an enormously important paper for surgeons and for children and families who are affected by CHD. Surgeons have been worried for years that the things we do during corrective heart surgery have the potential to affect the development of the brain. And we’ve learned to improve how we do heart surgery so that the procedure causes minimal damage to the brain. But we still see some kids who have behavioral problems and learning delays,” says Richard A. Jonas, M.D., Chief of the Division of Cardiac Surgery at Children’s National, and co-­senior study author. “We’re beginning to understand that there are things about CHD that affect the development of the brain before a baby is even born. What this paper shows is that the low oxygen level that sometimes results from a congenital heart problem might contribute to that and can slow down the growth of the brain. The good news is that it should be possible to reverse that problem using the cells that continue to develop in the neonate’s brain after birth.”

Among preclinical models, the spatiotemporal progression of brain growth in this particular model most closely parallels that of humans. Likewise, the SVZ cytoarchitecture of the neonatal preclinical model exposed to hypoxia mimics that of humans in utero and shortly after birth. The research team leveraged CellTracker Green to follow the path traveled by SVZ­ derived cells and to illuminate their fate, with postnatal SVZ supplying the developing cortex with newly generated neurons. SVZ­ derived cells were primarily neuroblasts. Superparamagnetic iron oxide nanoparticles supplied answers about long­ term SVZ migration, with SVZ ­derived cells making their way to the prefrontal cortex and the somatosensory cortex of the brain.

“We demonstrated that in the postnatal period, newly generated neurons migrate from the SVZ to specific cortices, with the majority migrating to the prefrontal cortex,” says Vittorio Gallo, Ph.D., Director of the Center for Neuroscience Research at Children’s National, and co­-senior study author. “Of note, we revealed that the anterior SVZ is a critical source of newborn neurons destined to populate the upper layers of the cortex. We challenged this process through chronic hypoxia exposure, which severely impaired neurogenesis within the SVZ, depleting this critical source of interneurons.”

In the preclinical model of hypoxia as well as in humans, brains were smaller, weighed significantly less and had a significant reduction in cortical gray matter volume. In the prefrontal cortex, there was a significant reduction in white matter neuroblasts. Taken as a whole, according to the study authors, the findings suggest that impaired neurogenesis within the SVZ represents a cellular mechanism underlying hypoxia ­induced, region ­specific reduction in immature neurons in the cortex. The prefrontal cortex, the region of the brain that enables such functions as judgment, decision­ making and problem solving, is most impacted. Impairments in higher ­order cognitive functions involving the prefrontal cortex are common in patients with CHD.

This is the consequential malfunction of the brain during congenital heart defects.

Congenital heart disease and white matter injury

This is the consequential malfunction of the brain during congenital heart defects.

Although recent advances have greatly improved the survival of children with congenital heart disease, up to 55 percent will be left with injury to their brain’s white matter – an area that is critical for aiding connection and communication between various regions in the brain.

What’s known

Eight of every 1,000 children born each year have congenital heart disease (CHD). Although recent advances have greatly improved the survival of these children, up to 55 percent will be left with injury to their brain’s white matter – an area that is critical for aiding connection and communication between various regions in the brain. The resulting spectrum of neurological deficits can have significant costs for the individual, their family and society. Although studies have demonstrated that white matter injuries due to CHD have many contributing factors, including abnormal blood flow to the fetal brain, many questions remain about the mechanisms that cause these injuries and the best interventions.

What’s new

A Children’s National Health System research team combed existing literature, reviewing studies from Children’s as well as other research groups, to develop an article detailing the current state of knowledge on CHD and white matter injury. The scientists write that advances in neuroimaging – including magnetic resonance imaging, magnetic resonance spectroscopy, Doppler ultrasound and diffusion tensor imaging – have provided a wealth of knowledge about brain development in patients who have CHD. Unfortunately, these techniques alone are unable to provide pivotal insights into how CHD affects cells and molecules in the brain. However, by integrating animal models with findings in human subjects and in postmortem human tissue, the scientists believe that it will be possible to find novel therapeutic targets and new standards of care to prevent developmental delay associated with cardiac abnormalities.

For example, using a porcine model, the Children’s team was able to define a strategy for white matter protection in congenital heart surgery through cellular and developmental analysis of different white matter regions. Another study from Children’s combined rodent hypoxia with a brain slice model to replicate the unique brain conditions in neonates with severe and complex congenital heart disease. This innovative animal model provided novel insights into the possible additive effect of preoperative hypoxia on brain insults due to cardiopulmonary bypass and deep hypothermic circulatory arrest.

The Children’s research team also recently published an additional review article describing the key windows of development during which the immature brain is most vulnerable to CHD-related injury.

Questions for future research

Q: Can we create an animal model that recapitulates the morphogenic and developmental aspects of CHD without directly affecting other organs or developmental processes?
Q: What are the prenatal and neonatal cellular responses to CHD in the developing brain?
Q: What are the molecular mechanisms underlying white matter immaturity and vulnerability to CHD, and how can we intervene?
Q: How can we accurately assess the dynamic neurological outcomes of CHD and/or corrective surgery in animal models?
Q: Prenatal or postnatal insults to the developing brain: which is most devastating in regards to developmental and behavioral disabilities?
Q: How can we best extrapolate from, and integrate, neuroimaging findings/correlations in human patients with cellular/molecular approaches in animal models?

Source: Reprinted from Trends in Neurosciences, Vol. 38/Ed. 6, Paul D. Morton, Nobuyuki Ishibashi, Richard A. Jonas and Vittorio Gallo, “Congenital cardiac anomalies and white matter injury,” pp. 353-363, Copyright 2015, with permission from Elsevier.

Vittorio Gallo

Vittorio Gallo named Chief Research Officer

Vittorio Gallo

As chief research officer, Vittorio Gallo, Ph.D., will be instrumental in developing and realizing Children’s Research Institute’s long-term strategic vision.

Children’s National Health System has appointed the longtime director of its Center for Neuroscience Research, Vittorio Gallo, Ph.D., as Chief Research Officer. Gallo’s appointment comes at a pivotal time for the institution’s research strategic plan, as significant growth and expansion will occur in the next few years. Gallo is a neuroscientist who studies white matter disorders, with particular focus on white matter growth and repair. He is also the Wolf-Pack Chair in Neuroscience at Children’s Research Institute, the academic arm of Children’s National.

As Chief Research Officer, Gallo will be instrumental in developing and realizing Children’s Research Institute’s long-term strategic vision, which includes building out the nearly 12-acre property once occupied by Walter Reed National Military Medical Center to serve as a regional innovation hub and to support Children’s scientists conducting world-class pediatric research in neuroscience, genetics, clinical and translational science, cancer and immunology. He succeeds Mendel Tuchman, M.D., who has had a long and distinguished career as Children’s Chief Research Officer for the past 12 years and who will remain for one year in an emeritus role, continuing federally funded research projects and mentoring junior researchers.

“I am tremendously pleased that Vittorio has agreed to become Chief Research Officer as of July 1, 2017, at such a pivotal time in Children’s history,” says Mark L. Batshaw, M.D., Physician-in-Chief and Chief Academic Officer at Children’s National. “Since Mendel announced plans to retire last summer, I spent a great deal of time talking to Children’s Research Institute investigators and leaders and also asking colleagues around the nation about the type of person and unique skill sets needed to serve as Mendel’s successor. With each conversation, it became increasingly clear that the most outstanding candidate for the Chief Research Officer position already works within Children’s walls,” Dr. Batshaw adds.

“I am deeply honored by being selected as Children’s next Chief Research Officer and am excited about being able to play a leadership role in defining the major areas of research that will be based at the Walter Reed space. The project represents an incredible opportunity to maintain the core nucleus of our research strengths – genetics, immunology, neurodevelopmental disorders and disabilities – and to expand into new, exciting areas of research. What’s more, we have an unprecedented opportunity to form new partnerships with peers in academia and private industry, and forge new community partnerships,” Gallo says. “I am already referring to this as Walter Reed ‘Now,’ so that we are not waiting for construction to begin to establish these important partnerships.”

Gallo’s research focus has been on white matter development and injury, myelin and glial cells – which are involved in the brain’s response to injury. His past and current focus is also on neural stem cells. His work in developmental neuroscience has been seminal in deepening understanding of cerebral palsy and multiple sclerosis. He came to Children’s National from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) intramural program. His intimate knowledge of the workings of the National Institutes of Health (NIH) has helped him to establish meaningful collaborations between both institutions. During his tenure, he has transformed the Center for Neuroscience Research into one of the nation’s premier programs. The Center is home to the prestigious NIH/NICHD-funded District of Columbia Intellectual and Developmental Disabilities Research Center, which Gallo directs.

Children’s research scientists working under the auspices of Children’s Research Institute conduct and promote highly collaborative and multidisciplinary research within the hospital that aims to better understand, treat and, ultimately, prevent pediatric disease. As Chief Research Officer, Gallo will continue to establish and enhance collaborations between research and clinical programs. Such cross-cutting projects will be essential in defining new mechanisms that underlie pediatric disease. “We know, for instance, that various mechanisms contribute to many genetic and neurological pediatric diseases, and that co-morbidities add another layer of complexity. Tapping expertise across disciplines has the potential to unravel current mysteries, as well as to better characterize unknown and rare diseases,” he says.

“Children’s National is among the nation’s top seven pediatric hospitals in NIH research funding, and the extraordinary innovations that have been produced by our clinicians and scientists have been put into practice here and in hospitals around the world,” Dr. Batshaw adds. “Children’s leadership aspires to nudge the organization higher, to rank among the nation’s top five pediatric hospitals in NIH research funding.”

Gallo says the opportunity for Children’s research to expand beyond the existing buildings and the concurrent expansion into new areas of research will trigger more hiring. “We plan to grow our research enterprise through strategic hires and by attracting even more visiting investigators from around the world. By expanding our community of investigators, we aim to strengthen our status as one of the nation’s leading pediatric hospitals,” he says.

Harnessing progenitor cells in neonatal white matter repair

The sirtuin protein Sirt1 plays a crucial role in the proliferation and regeneration of glial cells from an existing pool of progenitor cells — a process that rebuilds vital white matter following neonatal hypoxic brain injury. Although scientists do not fully understand Sirt1’s role in controlling cellular proliferation, this pre-clinical model of neonatal brain injury outlines for the first time how Sirt1 contributes to development of additional progenitor cells and maturation of fully functional oligodendrocytes.

The findings, published December 19 in Nature Communications, suggest that modulation of this protein could enhance progenitor cell regeneration, spurring additional white matter growth and repair following neonatal brain injury.

“It is not a cure. But, in order to regenerate the white matter that is lost or damaged, the first steps are to identify endogenous cells capable of regenerating lost cells and then to expand their pool. The glial progenitor cells represent 4 to 5 percent of total brain cells,” says Vittorio Gallo, Ph.D., Director of the Center for Neuroscience Research at Children’s National, and senior author of the study. “It’s a sizable pool, considering that the brain is made up of billions of cells. The advantage is that these progenitor cells are already there, with no requirement to slip them through the blood-brain barrier. Eventually they will differentiate into oligodendrocyte cells in white matter, mature glia, and that’s exactly what we want them to do.”

The study team identified Sirt1 as a novel, major regulator of basal oligodendrocyte progenitor cell (OPC) proliferation and regeneration in response to hypoxia in neonatal white matter, Gallo and co-authors write. “We demonstrate that Sirt1 deacetylates and activates Cdk2, a kinase which controls OPC expansion. We also elucidate the mechanism by which Sirt1 targets other individual members of the Cdk2 signaling pathway, by regulating their deacetylation, complex formation and E2F1 release, molecular events which drive Cdk2-mediated OPC proliferation,” says Li-Jin Chew, Ph.D., research associate professor at Children’s Center for Neuroscience Research and a study co-author.

Hypoxia-induced brain injury in neonates initiates spontaneous amplification of progenitor cells but also causes a deficiency of mature oligodendrocytes. Inhibiting Sirt1 expression in vitro and in vivo showed that loss of its deacetylase activity prevents OPC proliferation in hypoxia while promoting oligodendrocyte maturation – which underscores the importance of Sirt1 activity in maintaining the delicate balance between these two processes.

The tantalizing findings – the result of four years of research work in mouse models of neonatal hypoxia – hint at the prospect of lessening the severity of developmental delays experienced by the majority of preemies, Gallo adds. About 1 in 10 infants born in the United States are delivered preterm, prior to the 37th gestational week of pregnancy, according to the Centers for Disease Control and Prevention.  Brain injury associated with preterm birth – including white matter injury – can have long-term cognitive and behavioral consequences, with more than 50 percent of infants who survive prematurity needing special education, behavioral intervention and pharmacological treatment, Gallo says.

Time is of the essence, since Sirt1 plays a beneficial role at a certain place (white matter) and at a specific time (while the immature brain continues to develop). “We see maximal Sirt1 expression and activity within the first week after neonatal brain injury. There is a very narrow window in which to harness the stimulus that amplifies the progenitor cell population and target this particular molecule for repair,” he says.

Sirt1, a nicotinamide adenine dinucleotide-dependent class III histone deacetylase, is known to be involved in normal cell development, aging, inflammatory responses, energy metabolism and calorie restriction, the study team reports. Its activity can be modulated by sirtinol, an off-the-shelf drug that inhibits sirtuin proteins. The finding points to the potential for therapeutic interventions for diffuse white matter injury in neonates.

Next, the research team aims to study these processes in a large animal model whose brains are structurally, anatomically and metabolically similar to the human brain.

“Ideally, we want to be able to promote the timely regeneration of cells that are lost by designing strategies for interventions that synchronize these cellular events to a common and successful end,” Gallo says.