Multi-omics analysis revealed spermidine contributes to ovarian function improvement

Spermidine is involved in extensive cellular processes, including mammalian oocyte development. Wheat germ is a natural source of polyamines and contains high concentrations of spermidine. No studies have assessed the effects and mechanisms of action of wheat germ spermidine in regulating mammalian ovarian functions. Herein, a dietary experiment was conducted in mice administered wheat germ extract (WGE) for 90 days. Dietary WGE significantly increased spermidine absorption and affected the metabolism of the other polyamines (spermine and putrescine) in mouse intestines. Dietary intake of 50 g/kg WGE significantly increased the number of mouse pups per litter (p < 0.01), and the secreted levels of the sex hormones E2 and P4 (p < 0.05). Furthermore, compared with a normal diet, WGE feeding led to significantly greater ovarian reserves and fewer atretic follicles (p < 0.001). Finally, co-relationship analysis revealed gut microbes that significantly correlated with sex hormone levels. In summary, our results confirm that wheat germ spermidine plays a beneficial role in mouse ovarian function. Moreover, changes in the structure of the gut microbiota are likely to be crucial for improving ovarian function.