P380. Genetic Deficiency in Serotonin Transporter in Mice Alters Effects of Western Diet on Gut Microbiota

Serotonin transporter expression, besides implicated in serotonergic neurotransmission, is also involved in regulation of metabolic health. Animal work has shown gene x environment interactions, where serotonin transporter deficiency aggravated the effects of Western diet (a diet high in calories, saturated fat, sugar and cholesterol) on metabolic health and hippocampal-dependent behaviour. This transporter-dependent increased metabolic sensitivity to Western diet may be driven by the gut microbiota, as its expression affects gut microbial composition and metabolism of serotonin, lipids and steroids. Hence, variation in the gut microbiota due to differential serotonin transporter expression may result in differential susceptibility to the effects of Western diet on the gut microbiota and metabolic syndrome.