抗糖尿病药物二甲双胍(MET)大部分未被人体代谢。其残留物在各种水生环境中很容易检测到,并可能对水生物种的生长和生存产生不利影响。迄今为止,在非鱼类物种中几乎没有探索其毒理学作用。这里,我们将黑斑池塘蛙(Pelophylaxnigromaculatus)的t暴露于不同浓度(0、1、10和100μg/L)的MET中30天,并测量了身体大小,肠道微生物群和代谢产物,以评估两栖动物幼虫MET暴露的潜在影响。MET暴露不影响t的生长和肠道微生物多样性。然而,肠道微生物组成发生显著变化,与一些致病菌(例如,沙门氏菌属细菌,Comamonas,窄食单胞菌,三球菌)增加和一些有益细菌(例如,Blautia,Prevotella)在MET暴露的t中减少。MET暴露后,与生长和免疫性能相关的一些肠道代谢物的水平也发生了显着变化。总的来说,我们的结果表明,暴露于MET,即使在与环境相关的浓度下,会导致肠道微生物群失调和代谢物改变,从而影响非目标水生生物的健康状况,比如两栖动物。
The antidiabetic pharmaceutical metformin (MET) is largely unmetabolized by the human body. Its residues are readily detectable in various aquatic environments and may have adverse impacts on the growth and survival of aquatic species. To date, its toxicological effects have scarcely been explored in non-fish species. Here, we exposed the tadpoles of black-spotted pond frog (Pelophylax nigromaculatus) to different concentrations (0, 1, 10 and 100 μg/L) of MET for 30 days and measured the body size, intestinal microbiota and metabolites to evaluate potential effects of MET exposure in amphibian larvae. MET exposure did not affect the growth and intestinal microbial diversity of tadpoles. However, intestinal microbial composition changed significantly, with some pathogenic bacteria (e.g., bacterial genera Salmonella, Comamonas, Stenotrophomonas, Trichococcus) increasing and some beneficial bacteria (e.g., Blautia, Prevotella) decreasing in MET-exposed tadpoles. The levels of some intestinal metabolites associated with growth and immune performance also changed significantly following MET exposure. Overall, our results indicated that exposure to MET, even at environmentally relevant concentrations, would cause intestinal microbiota dysbiosis and metabolite alteration, thereby influencing the health status of non-target aquatic organisms, such as amphibians.