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Buffington et al (2016) and Reber et al. (2016)

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This week's articles were about the role of the gut-brain axis in neurodevelopment and stress. Reber and colleagues used a heat-killed version of the bacteria, M. vaccae, as a type of vaccine and found that administration to mouse models resulted in decreased response to chronic stress, prevented colitis related to stress, and reduced measures of anxiety. Reber et al. also used the inactivated M. vaccae in a mouse model of IBD and found that the bacteria prevented stress-induce flare-ups of colitis, but that this could be reversed by removing T cells. Buffington and colleagues instead examined the role of gut microbiota in maternal high-fat diets (MHFD) in the neurodevelopment and social behaviors of their offspring. Buffington et al. found that housing MHFD rats with the offspring of regular diet (MRD) rats prevented social deficits in their offspring. They also found that this co-housing arrangement prevented an imbalance in the gut bacteria

Reber and colleagues' findings were very intriguing to me, and hit kind of close to home. A little over a year ago, my parents adopted my little sister from Seoul. She's 3 years old, is very small for her age and has delayed speech and motor coordination. We spent the last year (and a variety of doctors and specialists) trying to diagnose the underlying cause for her inability to grow. She has IBD and ulcerative colitis which led to an inflamed gut, discomfort, and decreased appetite. After giving her a daily probiotic drink that meets her allergy needs, she now eats a lot better and has gained a few pounds. She has also been in speech therapy and OT, and has improved so much. But, she does still have anxiety, which is understandable due to the trauma she has experienced. Reber and colleagues' work had a very clear clinical translation—to use probiotics as a treatment for both a healthy gut, and healthy brain. Seeing how my sister has improved, and reading the findings of Reber et al.'s work, really has me convinced that this is a strong therapeutic option.

Buffington and colleagues' work was also very interesting, and I think it makes a good argument for prevention of neurodevelopmental disorders, like ASD. There are certainly many good reasons for mothers to have healthy diets during pregnancy aside from social factors, but the surprising part of this study was that co-habitating with a healthy rat's offspring had preventative factors for the pregnant mother's offspring. I'm not as convinced about this study, but its' findings were so interesting that I definitely think it warrants further investigation and I would be excited to see how future studies play out. The brain-gut axis is so cool!!!!

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