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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