Department of Toxicology, School of Public Health, Anhui Medical University, Hefei, China; Key Laboratory of Environmental Toxicology of Anhui Higher Education Institutes, Hefei, China.
Department of Rehabilitation Medicine, The Second Hospital of Anhui Medical University, Hefei, China.
Sci Total Environ. 2021 Jul 10;777:146006. doi: 10.1016/j.scitotenv.2021.146006. Epub 2021 Feb 22.
Cadmium (Cd), a noxious heavy metal, is widespread in the living environment. Gestational exposure to Cd at environmental dose has been shown to cause fetal growth restriction (FGR). However, the long-term effects and the mechanisms underlying environmental Cd exposure on glucose metabolism in offspring remain unclear. Here, we established a murine model to study the impacts of gestational exposure to environmental Cd on glucose metabolism at different life stages of offspring. Results demonstrated that the offspring mice developed hyperglycemia in puberty and impaired glucose tolerance in adulthood following maternal Cd exposure during gestation. Further mechanistic investigation showed that Cd exposure upregulated the expression of key proteins in hepatic gluconeogenesis, including p-CREB, PGC-1α and G6PC, in pubertal and adult offspring. In addition, we demonstrated that Cd exposure during pregnancy markedly elevated the level of oxidative stress-related proteins, including NOX2, NOX4 and HO-1, in the fetal liver. The effects of gestational exposure to N-acetylcysteine (NAC), a free-radical scavenging antioxidant, presented that NAC supplementation alleviated hepatic oxidative stress in fetuses, and thereby reversed hyperglycemia and glucose intolerance in mouse offspring. Collectively, our data suggested that gestational exposure to environmental Cd caused diabetes-like phenotypes via enhancing hepatic gluconeogenesis, which is associated with oxidative stress in fetal livers. This work provides new insights into the protective effects of antioxidants on fetal-originated diabetes triggered by environmental toxicants.
镉(Cd)是一种有毒重金属,广泛存在于生活环境中。环境剂量的妊娠期镉暴露已被证明会导致胎儿生长受限(FGR)。然而,环境镉暴露对后代葡萄糖代谢的长期影响和机制仍不清楚。在这里,我们建立了一个小鼠模型来研究妊娠期暴露于环境镉对后代不同生命阶段葡萄糖代谢的影响。结果表明,母体妊娠期镉暴露后,后代小鼠在青春期出现高血糖,成年后出现葡萄糖耐量受损。进一步的机制研究表明,镉暴露上调了青春期和成年后代肝脏糖异生关键蛋白的表达,包括 p-CREB、PGC-1α 和 G6PC。此外,我们还证明,妊娠期暴露于镉会显著增加胎儿肝脏中氧化应激相关蛋白的水平,包括 NOX2、NOX4 和 HO-1。妊娠期暴露于 N-乙酰半胱氨酸(NAC),一种自由基清除抗氧化剂的实验结果表明,NAC 补充缓解了胎儿肝脏的氧化应激,从而逆转了小鼠后代的高血糖和葡萄糖耐量受损。总之,我们的数据表明,妊娠期暴露于环境镉通过增强肝脏糖异生导致类似糖尿病的表型,这与胎儿肝脏的氧化应激有关。这项工作为抗氧化剂对环境毒物引起的胎儿起源性糖尿病的保护作用提供了新的见解。