Gut microbial metabolism of dietary fiber protects against high-energy feeding induced ovarian follicular atresia in a pig model.

To investigate the effects of dietary fiber on follicular atresia in pigs fed a high-fat diet, we fed 32 prepubescent gilts a basal diet (CON) or a CON diet supplemented with 300 g/d dietary fiber (fiber), 240 g/d soy oil (SO), or both (fiber + SO). At the 19th day of the 4th estrus cycle, gilts fed the SO diet showed 112% more atretic follicles and greater expression of the apoptotic markers, Bax and Caspase-3, and these effects were reversed by the fiber diet. The abundance of short-chain fatty acid-producing microbes was decreased by the SO diet, but this effect was reversed by fiber treatment. Concentrations of serotonin and melatonin in the serum and follicular fluid were increased by the fiber diet. Overall, dietary fiber protected against high-fat feeding induced follicular atresia at least partly via gut microbiota-related serotonin-melatonin synthesis. These results provide insight into preventing negative effects on fertility in humans consuming a high-energy diet.