College of Fisheries, Henan Normal University, Xinxiang 453007, PR China.
State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, PR China.
Ecotoxicol Environ Saf. 2018 Sep 30;160:257-264. doi: 10.1016/j.ecoenv.2018.05.050. Epub 2018 May 28.
The present study was conducted to determine the effects of waterborne copper exposure on the lipid metabolism and intestinal microbiota of juvenile common carp (Cyprinus carpio L.). Common carp were exposed to four waterborne copper (Cu) concentrations (0 (control), 0.07 (low), 0.14 (medium), and 0.28 (high) mg Cu/L) for 8 weeks. Exposure to a high concentration of Cu had a negative effect on growth indices (weight gain rate (WGR) and specific growth rate (SGR)). The biochemical indices measured in serum (low-density lipoprotein (LDL) and triglycerides (TGs)) were significantly affected by exposure to medium concentration levels of Cu. The mRNA levels of lipogenic enzymes (acetyl-CoA carboxylase 1 (ACC-1) and fatty acid synthase (FAS)) and sterol-regulator element-binding protein-1 (SREBP-1) in liver tissue and tight binding protein genes (ZO-1 and occludin) in intestinal epithelial tissue were significantly downregulated in the 0.14 and 0.28 mg/L Cu treatment groups, accompanied by upregulated mRNA levels of lipolysis enzymes (lipoprotein lipase (LPL) and carnitine palmitoyl transferase 1 (CPT-1)) in the liver. The data also showed that the composition of intestinal microbiota was changed following Cu exposure and could alter the α-diversity and β-diversity. The abundances of few putative short-chain fatty acid (SCFA)-producing bacteria, including Allobaculum, Blautia, Coprococcus, Faecalibacterium, Roseburia, and Ruminococcus, decreased significantly. More specifically, Roseburia sequences were positively associated with lipogenic enzymes, total protein (TP), and TGs and negatively associated with lipolysis enzymes. Other sequences related to probiotics (Lactobacillus, Bacillus and Akkermansia) were also found to decrease, accompanied by an increase in sequences related to pathogens (Pseudomonas and Acinetobacter). To the best of our knowledge, the present study provides the first evidence that waterborne, chronic Cu exposure can disturb the composition of intestinal microbiota related to lipid metabolism and immunity in freshwater fish, thereby increasing the risk of pathogen invasion.
本研究旨在探讨水铜暴露对幼鲤（Cyprinus carpio L.）脂代谢和肠道微生物群的影响。将鲤鱼暴露于四种水铜（Cu）浓度（0（对照）、0.07（低）、0.14（中）和 0.28（高）mg Cu/L）中 8 周。高浓度 Cu 暴露对生长指数（增重率（WGR）和特定生长率（SGR））有负面影响。血清中测量的生化指标（低密度脂蛋白（LDL）和甘油三酯（TGs））受到中等浓度 Cu 暴露的显著影响。肝组织中脂肪生成酶（乙酰辅酶 A 羧化酶 1（ACC-1）和脂肪酸合成酶（FAS）和固醇调节元件结合蛋白-1（SREBP-1）的 mRNA 水平以及肠上皮组织中的紧密结合蛋白基因（ZO-1 和 occludin）在 0.14 和 0.28 mg/L Cu 处理组中显著下调，同时肝中脂肪分解酶（脂蛋白脂肪酶（LPL）和肉碱棕榈酰转移酶 1（CPT-1））的 mRNA 水平上调。数据还表明，Cu 暴露后肠道微生物群的组成发生了变化，并可能改变 α-多样性和 β-多样性。少数假定的短链脂肪酸（SCFA）产生菌的丰度降低，包括 Allobaculum、Blautia、Coprococcus、Faecalibacterium、Roseburia 和 Ruminococcus。更具体地说，Roseburia 序列与脂肪生成酶、总蛋白（TP）和 TGs 呈正相关，与脂肪分解酶呈负相关。还发现与益生菌（乳杆菌、芽孢杆菌和 Akkermansia）相关的其他序列减少，同时与病原体（假单胞菌和不动杆菌）相关的序列增加。据我们所知，本研究首次提供了水铜慢性暴露会扰乱淡水鱼与脂代谢和免疫相关的肠道微生物群组成的证据，从而增加病原体入侵的风险。
