Maternal High‐Fat Diet Results in Long‐Term Sex‐Specific Alterations to Metabolic and Gut Microbial Diurnal Oscillations in Adult Offspring

Abstract Scope: Circadian rhythms profoundly impact metabolism and the gut microbiota. A maternal high‐fat diet (HFD) exerts effects on the metabolic syndrome of adult offspring in a sex‐specific manner, the underlying mechanisms, however, remain unclear. Methods and results: Female mice are fed an HFD and raise their offspring on a standard chow diet until 24 weeks. The glucose tolerance, insulin sensitivity, and diurnal rhythms of serum metabolic profiles are assessed in male and female adult offspring. Simultaneously, 16S rRNA is applied to characterize gut microbiota diurnal rhythms. The study finds that maternal HFD tends to deteriorate glucose tolerance and impairs insulin sensitivity in male offspring, but not female offspring, which can be associated with the circadian alterations of serum metabolic profiles in male offspring. As expected, maternal HFD sex‐specifically alters diurnal rhythms of the gut microbiota, which exhibits putative associations with metabolic profiles in males. Conclusions: The present study identifies the critical role of gut microbiota diurnal rhythms in triggering sex‐biased metabolic diurnal rhythms in response to maternal HFD, at least in part. As early life may be a critical window for preventing metabolic diseases, these findings provide the basis for developing chronobiology applications targeting the gut microbiota to combat early metabolic alterations, especially in males.