In utero and lactational exposure to BDE-47 promotes obesity development in mouse offspring fed a high-fat diet: impaired lipid metabolism and intestinal dysbiosis

Dezhen Wang, Jin Yan, Miaomiao Teng, Sen Yan, Zhiqiang Zhou, Wentao Zhu

In this study, we investigated the effects of in utero and lactational exposure to BDE-47 on the progression of obesity and metabolic dysfunction in a diet-induced obesity model. Pregnant ICR mice were treated via oral gavage with low doses of BDE-47 (0, 0.002, and 0.2 mg/kg body weight) from gestational day 6 to postnatal day 21. After weaning, male offspring were fed an AIN93-based normal diet (ND) or high-fat diet (HFD: 60% calories from fat) for 14 weeks. We examined body weight, liver weight, histopathology, blood biochemistry, gene expression, and serum metabolic changes. A combination of 16S rRNA gene sequencing and1H NMR-based metabolomics was conducted to examine the effects of BDE-47 on the gut microbiome. Results showed that in utero and lactational exposure to BDE-47 caused a worsening of HFD-induced obesity, hepatic steatosis, and injury; impaired glucose homeostasis and metabolic dysfunction, and mRNA levels of genes involved in lipid metabolism were significantly altered in the BDE-47-treated HFD group. The gut microbiome were perturbed by BDE-47, causing diversity reduction, compositional alteration, and metabolic changes. These changes were more pronounced for BDE-47-treated HFD mice. All these results indicate that early life exposure to low doses of BDE-47 can promote obesity and the development of metabolic dysfunction.