Sexually Dimorphic Regulation of Gut Microbiota and Body Weight by a Naturally Occurring Flavonoid

Abstract

Objectives 7,8-Dihydroxyflavone (DHF) is a naturally occurring flavonoid that is being actively investigated as a therapeutic modality in the treatment of neurological disorders. A recent study also indicated that oral DHF supplementation protected female but not male mice from diet-induced obesity. However, the mechanisms underlying this sexually-dimorphic effects of DHF were not known. The aim of the work is to investigate the mechanisms underlying sex-specific effects of flavonoid. Methods Age-matched male and female mice were given ad libitum access to high fat-diet and drinking water containing vehicle or DHF for 12 weeks. Body weights, body composition, food, and water intake, were assessed. Immunohistological analysis, immunohistochemistry staining, plasma triglycerides, plasma bile acids, and hepatic lipids were investigated. Fresh fecal samples were collected, genomic DNA was extracted and hypervariable region V4 of the 16S rRNA gene was amplified. Gut microbiota structure was evaluated using alpha diversity indices and beta diversity distance metrices. Principal coordinates analysis (PCoA) was performed using the R “ape” package to visualize differences in gut microbiota structure between treatment groups along principal coordinates that accounted for most of the variations. Results Oral administration of DHF, remodels the intestinal microbiome of female, but not male, prior to divergence in body weight. This is concomitant with increase in brown adipose tissue thermogenesis, mediated by increased expression of UCP1 and Pgc -1α protecting the female mice from diet-induced obesity. Conclusions This study demonstrates sexually-dimorphic effects of a clinically relevant natural compound. Importantly, it points to a role for sex-dependent remodeling of the intestinal microbiome as a mechanism for weight control in females. Thus, our discoveries pave the way for personalized nutrition strategies that account for sex differences in metabolism. Funding Sources NIH.