GASTROENTEROLOGY
Advances and Answers in Pediatric Health
A Gut Feeling
Pediatric gastroenterologist Jaime Belkind-Gerson, MD, MSc, is the Director of the Children’ s Hospital Colorado Neurogastroenterology and Motility Program and the University of Colorado enteric nervous system lab. Through years of extensive research, he knew the microbiome played a role in gut health. He recently learned just how big that role is, though, through the findings of two separate but related studies.
REPOPULATING THE GUT MICROBIOME
In one study, Dr. Belkind-Gerson and his team detail their work with a mouse model. A mix of three antibiotics were given daily for three weeks to eliminate most of the microbiome. The gut with the abnormal intestinal bacteria had a 30 % decrease of neurons within the myenteric and submucosal plexuses. Functionally, that meant global intestinal motility was slowed and markedly abnormal. When they removed the antibiotics and allowed the microbiome to repopulate, neuronal number and motility returned to normal. Clearly, bacteria stimulate neurogenesis and help correct function. But how? Part of what they found is that short-chain fatty acids produced by the bacteria seem to communicate with the body, protect the neurons and stimulate nervous system regeneration.
DISCOVERING A SCHWANN CELL PATHWAY
Schwann cells, or SC, produce the myelin around peripheral nerves and are critical for development, maintenance and function of the nerve. But there’ s no myelin in the gut, so why are there SC markers in the intestine? In mice, a recent observation is that an immature form of SC create extraintestinal autonomic ganglion cells during embryonic development. Those cells migrate into the gut shortly before or after birth to become colonic enteric neurons. Could the same be true in humans?
In a study recently awarded a best abstract by the North American Society of Pediatric Gastroenterology, Hepatology and Nutrition, Dr. Belkind-Gerson and his team observed rectal specimens resected during pull-through surgery for anorectal malformations. They found that neurons within or near the human colon stain positively to several SC immune markers. SC have a similar embryonic origin( the neural crest) to the neurons and glia in the gut— they’ re cousins. As in mice, the SC closest to the gut migrate when needed, changing their morphology and function, becoming different cells that repair damage and replenish neuronal mass and connections. •
Dr. Belkind-Gerson plans to publish both papers in the coming months. Look for more in an upcoming edition of Q: Magazine.
“ We now know gut bugs are extremely important, working in part to stimulate neurogenesis.”
JAIME BELKIND-GERSON, MD, MSC
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