This study aimed to investigate how obesity induced by a high-energy diet (HED) during pregnancy affects maternal gut microbiota, energy metabolism, intestinal barrier function, and body fat remodeling using C57BL/6J mice as the model. Results show that HED significantly increased maternal weight gain and adiposity and increased maternal body fat percentage ( P < 0.01). Serum biochemical indicators showed that HED elevated the energy metabolic burden on pregnant mothers ( P < 0.01). Notably, HED inhibited fat type conversion during pregnancy, worsening maternal obesity ( P < 0.01). Physical damage to the maternal liver and small intestine was observed, activating gut immunity and reducing gut antioxidant properties ( P < 0.01). However, increased expression of fatty acid transporters in the small intestine and an elevated villus height to crypt depth ratio accelerated maternal fatty acid absorption ( P < 0.01). Significant alterations in the maternal gut microbiota were identified, with key microorganisms such as Adlercreutzia, Anaerotruncus, Bifidobacterium, Roseburia, Alistipes, Mucispirillum, Lactococcus, Ruminococcus, Bacteroides, and Allobaculum showing correlations with maternal energy metabolism, gut health, and body fat conversion. This study elucidated the impact of HED on maternal gut microbiota, energy metabolism, gut health, and body fat conversion during pregnancy, highlighting a significant connection between gut microbiota and maternal health. • High-energy diet (HED) not only exacerbates maternal obesity but also impairs thermogenic capacity. • HED induces structural damage to the intestinal barrier, triggering a pro-inflammatory cytokine storm, particularly in the jejunum. • HED significantly alters maternal gut microbiota composition and enhances nutrient transport capacity. • Gut microbiota dysbiosis is a key factor in the deterioration of maternal health.
He et al. (2026) studied this question.