College of Agriculture and Biotechnology, Hunan University of Humanities, Science and Technology, Loudi 417000, Hunan, China.
College of Agriculture and Biotechnology, Hunan University of Humanities, Science and Technology, Loudi 417000, Hunan, China.
Environ Toxicol Pharmacol. 2022 Aug;94:103926. doi: 10.1016/j.etap.2022.103926. Epub 2022 Jul 3.
Cadmium (Cd) is an environmental endocrine-disrupting pollutant which mainly occurs in pulsed manner in natural waters, while traditional toxicology experiments have less examined the effects of pulsed exposure. Here, we studied the effects of short-term (7 days) continuous and pulse exposure to 100 μg/L Cd on gut morphology and microbiota of frogs (Pelophylax nigromaculatus) during pre-hibernation. Compared to continuous exposure, Cd pulse exposure significantly increased individual mortality and decreased the villi height and the ratio of villi height to crypt depth of the gut. Cd continuous and pulse exposure both changed the community structure and relative abundance of intestinal microbiota. Compared to continuous exposure, Cd pulse exposure significantly decreased the relative abundance of beneficial bacteria (e.g., Cetobacterium and Aeromonas genus), and significantly increased the relative abundance of harmful bacteria (e.g., Parabacteroides, Odoribacter, and Acinetobacter genus). This study shows that the gut histology and microbiota of amphibians during pre-hibernation are more susceptible to Cd pulse exposure than continuous exposure.
镉（Cd）是一种环境内分泌干扰污染物，主要以脉冲方式出现在天然水中，而传统毒理学实验对脉冲暴露的影响研究较少。在这里，我们研究了在冬眠前，短期（7 天）连续和脉冲暴露于 100μg/L Cd 对青蛙（黑斑蛙）肠道形态和微生物群的影响。与连续暴露相比，Cd 脉冲暴露显著增加了个体死亡率，并降低了肠道的绒毛高度和绒毛高度与隐窝深度的比值。Cd 连续和脉冲暴露均改变了肠道微生物群落结构和相对丰度。与连续暴露相比，Cd 脉冲暴露显著降低了有益菌（如 Cetobacterium 和 Aeromonas 属）的相对丰度，显著增加了有害菌（如 Parabacteroides、Odoribacter 和 Acinetobacter 属）的相对丰度。本研究表明，冬眠前两栖动物的肠道组织学和微生物群对 Cd 脉冲暴露比连续暴露更敏感。
