Monitored food intake in early pregnancy modulates the maternal microbiome in the obese BPH/5 mouse model of superimposed preeclampsia.

Abstract

Preeclampsia (PE) is a life-threatening pregnancy disorder strongly associated with maternal obesity, yet the mechanistic links between diet, microbiome, and disease risk remain unclear. The obese BPH/5 mouse, which spontaneously develops PE-like features, provides a model to investigate how maternal nutrition influences microbial and metabolic profiles. Here, we tested the effects of modest caloric restriction [pair-fed (PF)] initiated at(e0.5) on maternal microbiota and circulating metabolites at(e7.5). Microbial communities were profiled by 16S rRNA sequencing across fecal, oral, and vaginal niches, and serum short-chain fatty acids (SCFAs) were quantified by gas chromatography mass spectrometry. The PF BPH/5 dams exhibited a markedly reduced Firmicutes-to-Bacteroidetes ratio and increased abundance ofandin fecal samples, which are taxa associated with improved metabolic balance and gut barrier support. In contrast, PF increased Proteobacteria abundance in BPH/5 vaginal and oral sites, a shift linked to inflammation and barrier dysfunction. Serum acetic acid was significantly decreased in PF BPH/5 dams and their offspring, suggesting that restricted intake lowers systemic SCFA availability. These findings demonstrate that early pregnancy caloric restriction produces both beneficial and adverse microbial shifts, suggesting that high-fiber dietary interventions that enhance SCFA production may better support maternal-fetal health than caloric restriction alone.Caloric restriction via monitored food intake in early pregnancy reshaped the maternal microbiome in obese BPH/5 mice, lowering fecal F/B ratios and enrichingand, while simultaneously reducing systemic acetic acid and increasing Proteobacteria in vaginal and oral sites. These findings reveal that diet-microbiome interactions in early gestation exert both beneficial and detrimental effects, underscoring the need for alternative interventions, potentially high-fiber, to support SCFA production and maternal-fetal health.