水体铜对鲤肠道菌群结构及免疫力的影响

为了解水体重金属铜对鲤肠道菌群多样性、结构及免疫力的影响,以不同质量浓度的水体铜胁迫鲤56d,对鲤肠道菌群α多样性、β多样性、基于属水平的群落组成结构及肠道免疫调控因子和紧密连接蛋白的基因表达进行了分析.结果显示,0.14mg·L-1、0.28mg·L-1处理组与对照组相比,α多样性指数有显著性下降(P0.01),主成分分析(PCA)显示两处理组与对照组群落组成区分明显,优势菌群发生明显变化;同时,两处理组肠道免疫调控因子Il-1β,IL-8,TNF-α及信号分子NF-κB基因表达有显著增加(P0.01),肠道紧密连接蛋白Claudin-3,Claudin-c及免疫调控因子IL-10、信号分子TOR基因表达有显著下降(P0.01).结果表明:中、高质量浓度水体铜胁迫显著降低了鲤肠道菌群的多样性,改变了结构组成,对鲤肠道上皮免疫屏障造成了损伤.

Effect of waterborn copper on the intestinal microbiota and immunity of common carp(Cyprinus carpio L)

In order to clarify the effect of waterborn copper on the intestinal microbiota and immunity of common carp,diversity indexes analysis and abundance changes of the microbiota based on genus level were carried out.Also,mRNA expression level analysis about the immunity factors and tight junction protein in the gut were done.The result showed that the Shannon index and observed species were significantly decreased in 0.14 mg·L~(-1),0.28 mg·L~(-1) treatment group.The composition of the microbiota in these two groups were also observed obviously different with the control or 0.07 mg·L~(-1) treatment group according to PCA analysis.Moreover,the major abundance of the microflora at the genus level were changed in the two treatments following Cu exposure.The mRNA expression level about the proinflammatory cytokines(Ilr-1β,IL-8,TNF-α)and signal molecular of regulation pathway(NF-κB)were detected significantly up-regulated in 0.14 mg·L~(-1),0.28 mg·L~(-1) treatment group.However,tight connection protein(Claudin-3、Claudin-c)and antiflammatory cytokines(IL~(-1)0),signal molecular(TOR)were found down-regulated conversely.In conclusion:waterborne copper exposure significantly decreased the microflora diversity and changed the community structure of the intestinal microbiota of common carp,accompanied with severely immunity damage.