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blood glucose monitoring system

Patterns of continuous glucose monitoring use in young children after T1D diagnosis

blood glucose monitoring system

The findings suggest that, when clinically appropriate, continuous glucose monitoring initiation near or at the time of diagnosis benefits glycemic outcomes in young children when followed by sustained use.

Continuous glucose monitoring (CGM) is a blood glucose monitoring device worn on the body that is linked to positive glycemic outcomes in people with Type 1 diabetes (T1D). However, very little research has examined CGM use and glycemic outcomes in young children, particularly those newly diagnosed with T1D.

A new Diabetes Technology and Therapeutics study led by Randi Streisand, Ph.D., C.D.C.E.S., Chief of Psychology and Behavioral Health at Children’s National Hospital, and others identified four meaningful trajectories of CGM use among young children across 18-months post-T1D diagnosis: those who “always” used CGM; those who got on CGM later but stayed on it (“late/stable”); those who used CGM inconsistently; and those who “never” used CGM. The investigators conducted a study of 157 parents of young children (1-6 years) newly diagnosed with T1D who enrolled in a behavioral intervention.

Importantly, the authors found that those with private insurance were more likely than those with only public insurance to be in the “always” and “late/stable” groups (as opposed to the “never” group). Those in the “always” and “late/stable” groups also had better glycemic outcomes than those in the “never group” at 18-months post-T1D diagnosis.

“This research highlights that insurance type can be a barrier to accessing CGM,” Dr. Streisand noted. “Further, this is one of the first studies, among newly diagnosed young children, to show that CGM initiation at diagnosis or near diagnosis followed by sustained use is associated with better glycemic outcomes compared to never initiating CGM, supporting findings from other studies conducted with older youth.”

The findings inform clinical care with patients as it suggests that, when clinically appropriate, CGM initiation near or at the time of diagnosis benefits glycemic outcomes in young children when followed by sustained use. This is the only study to examine patterns of CGM use among 1-6-year-old children newly diagnosed with T1D over the first 18-months post-diagnosis.

“It was exciting to find differences in glycemic outcomes based on CGM initiation and use in this unique population,” Dr. Streisand said. However, the authors concluded that, given the health benefits of CGM, further exploration of barriers to CGM access and use among some families is needed.

In addition to Dr. Streisand, other Children’s National co-authors include Brynn Marks, M.D., M.S. HPEd.; Carrie Tully, Ph.D.Maureen Monaghan, Ph.D., C.D.E. , and Christine Wang, Ph.D.

brain network illustration

$2.5M to protect the brain from metabolic insult

brain network illustration

The brain comprises only 2% of the body’s volume, but it uses more than 20% of its energy, which makes this organ particularly vulnerable to changes in metabolism.

More than 30 million Americans have diabetes, with the vast majority having Type 2 disease. Characterized by insulin resistance and persistently high blood sugar levels, poorly controlled Type 2 diabetes has a host of well-recognized complications: compared with the general population, a greatly increased risk of kidney disease, vision loss, heart attacks and strokes and lower limb amputations.

But more recently, says Nathan A. Smith, MS, Ph.D., a principal investigator in Children’s National Research Institute’s Center for Neuroscience Research, another consequence has become increasingly apparent. With increasing insulin resistance comes cognitive damage, a factor that contributes significantly to dementia diagnoses as patients age.

The brain comprises only 2% of the body’s volume, but it uses more than 20% of its energy, Smith explains – which makes this organ particularly vulnerable to changes in metabolism. Type 2 diabetes and even prediabetic changes in glucose metabolism inflict damage upon this organ in mechanisms with dangerous synergy, he adds. Insulin resistance itself stresses brain cells, slowly depriving them of fuel. As blood sugar rises, it also increases inflammation and blocks nitric oxide, which together narrow the brain’s blood vessels while also increasing blood viscosity.

When the brain’s neurons slowly starve, they become increasingly inefficient at doing their job, eventually succumbing to this deprivation. These hits don’t just affect individual cells, Smith adds. They also affect connectivity that spans across the brain, neural networks that are a major focus of his research.

While it’s well established that Type 2 diabetes significantly boosts the risk of cognitive decline, Smith says, it’s been unclear whether this process might be halted or even reversed. It’s this question that forms the basis of a collaborative Frontiers grant, $2.5 million from the National Science Foundation split between his laboratory; the lead institution, Stony Brook University; and Massachusetts General Hospital/Harvard Medical School.

Smith and colleagues at the three institutions are testing whether changing the brain’s fuel source from glucose to ketones – byproducts from fat metabolism – could potentially save neurons and neural networks over time. Ketones already have shown promise for decades in treating some types of epilepsy, a disease that sometimes stems from an imbalance in neuronal excitation and inhibition. When some patients start on a ketogenic diet – an extreme version of a popular fat-based diet – many can significantly decrease or even stop their seizures, bringing their misfiring brain cells back to health.

Principal Investigator Smith and his laboratory at the Children’s National Research Institute are using experimental models to test whether ketones could protect the brain against the ravages of insulin resistance. They’re looking specifically at interneurons, the inhibitory cells of the brain and the most energy demanding. The team is using a technique known as patch clamping to determine how either insulin resistance or insulin resistance in the presence of ketones affect these cells’ ability to fire.

They’re also looking at how calcium ions migrate in and out of the cells’ membranes, a necessary prerequisite for neurons’ electrical activity. Finally, they’re evaluating whether these potential changes to the cells’ electrophysiological properties in turn change how different parts of the brain communicate with each other, potentially restructuring the networks that are vital to every action this organ performs.

Colleagues at Athinoula A. Martinos Center for Biomedical Imaging at Massachusetts General Hospital and Harvard Medical School, led by Principal Investigator Eva-Maria Ratai, Ph.D.,  will perform parallel work in human subjects. They will use imaging to determine how these two fuel types, glucose or ketones, affect how the brain uses energy and produces the communication molecules known as neurotransmitters. They’re also investigating how these factors might affect the stability of neural networks using techniques that investigate the performance of these networks both while study subjects are at rest and performing a task.

Finally, colleagues at the Laufer Center for Physical and Quantitative Biology at Stony Brook University, led by Principal Investigator Lilianne R. Mujica-Parodi, Ph.D., will use results generated at the other two institutions to construct computational models that can accurately predict how the brain will behave under metabolic stress: how it copes when deprived of fuel and whether it might be able to retain healthy function when its cells receive ketones instead of glucose.

Collectively, Smith says, these results could help retain brain function even under glucose restraints. (For this, the research team owes a special thanks to Mujica-Parodi, who assembled the group to answer this important question, thus underscoring the importance of team science, he adds.)

“By supplying an alternate fuel source, we may eventually be able to preserve the brain even in the face of insulin resistance,” Smith says.

Catherine Limperopoulos

Breastfeeding boosts metabolites important for brain growth

Catherine Limperopoulos

“Proton magnetic resonance spectroscopy, a non-invasive imaging technique that describes the chemical composition of specific brain structures, enables us to measure metabolites that may play a critical role for growth and explain what makes breastfeeding beneficial for newborns’ developing brains,” says Catherine Limperopoulos, Ph.D.

Micro-preemies who primarily consume breast milk have significantly higher levels of metabolites important for brain growth and development, according to sophisticated imaging conducted by an interdisciplinary research team at Children’s National.

“Our previous research established that vulnerable preterm infants who are fed breast milk early in life have improved brain growth and neurodevelopmental outcomes. It was unclear what makes breastfeeding so beneficial for newborns’ developing brains,” says Catherine Limperopoulos, Ph.D., director of MRI Research of the Developing Brain at Children’s National. “Proton magnetic resonance spectroscopy, a non-invasive imaging technique that describes the chemical composition of specific brain structures, enables us to measure metabolites essential for growth and answer that lingering question.”

According to the Centers for Disease Control and Prevention, about 1 in 10 U.S. infants is born preterm. The Children’s research team presented their findings during the Pediatric Academic Societies 2019 Annual Meeting.

The research-clinicians enrolled babies who were very low birthweight (less than 1,500 grams) and 32 weeks gestational age or younger at birth when they were admitted to Children’s neonatal intensive care unit in the first week of life. The team gathered data from the right frontal white matter and the cerebellum – a brain region that enables people to maintain balance and proper muscle coordination and that supports high-order cognitive functions.

Each chemical has its own a unique spectral fingerprint. The team generated light signatures for key metabolites and calculated the quantity of each metabolite. Of note:

  • Cerebral white matter spectra showed significantly greater levels of inositol (a molecule similar to glucose) for babies fed breast milk, compared with babies fed formula.
  • Cerebellar spectra had significantly greater creatine levels for breastfed babies compared with infants fed formula.
  • And the percentage of days infants were fed breast milk was associated with significantly greater levels of both creatine and choline, a water soluble nutrient.

“Key metabolite levels ramp up during the times babies’ brains experience exponential growth,” says Katherine M. Ottolini, the study’s lead author. “Creatine facilitates recycling of ATP, the cell’s energy currency. Seeing greater quantities of this metabolite denotes more rapid changes and higher cellular maturation. Choline is a marker of cell membrane turnover; when new cells are generated, we see choline levels rise.”

Already, Children’s National leverages an array of imaging options that describe normal brain growth, which makes it easier to spot when fetal or neonatal brain development goes awry, enabling earlier intervention and more effective treatment. “Proton magnetic resonance spectroscopy may serve as an important additional tool to advance our understanding of how breastfeeding boosts neurodevelopment for preterm infants,” Limperopoulos adds.

Pediatric Academic Societies 2019 Annual Meeting presentation

  • “Improved cerebral and cerebellar metabolism in breast milk-fed VLBW infants.”
    • Monday, April 29, 2019, 3:30–3:45 p.m. (EST)

Katherine M. Ottolini, lead author; Nickie Andescavage, M.D., Attending, Neonatal-Perinatal Medicine and co-author; Kushal Kapse, research and development staff engineer and co-author; Sudeepta Basu, M.D., neonatologist and co-author; and Catherine Limperopoulos, Ph.D., director of MRI Research of the Developing Brain and senior author, all of Children’s National.