普洱茶对慢性铅暴露致肾炎症损伤的保护作用及机制研究

Research on the Protection and Mechanism of Pu′er Tea on the Renal Inflammation Injury Resulted by Chronic Lead Treatment

铅(Pb)是环境中重要的无机污染物之一,可造成多系统多器官的损伤,肾脏是铅毒性的主要靶器官。铅能造成肾小管、肾小球的炎症损伤,导致肾间质纤维化,其主要机制为氧化应激、细胞凋亡等,本试验前期研究发现,慢性铅暴露可导致甲基乙二醛(Methylglyoxal,MG)在肾组织中累积。MG是广泛分布的邻二羰基化合物,具有两个高活性的羰基亲电中心,可与DNA、RNA中的核碱基和蛋白质中的碱性残基反应,通过AGEs-RAGE-NFκB通路促进炎性损伤。普洱茶为云南特色名茶,本实验利用不同剂量的普洱茶灌胃铅暴露模型鼠,观察普洱茶对小鼠全血铅水平、肾脏组织中MG含量、前炎症因子TNF-α、1L-1β、AGEs的受体蛋白RAGE和核转录因子NFκB表达的影响。结果显示,一定浓度的普洱茶不仅能起到促排铅效果,还能直接螯合组织中的MG,减少铅暴露所致MG的过量累积,减少AGEs的形成,降低其受体蛋白RAGE的表达,减少NFκB的磷酸化,降低TNF-α、1L-1β的量,减轻炎症损伤,最终起到保护肾脏的作用。

Lead（Pb） is one of the most important inorganic contaminants in the environment, which can cause multiple systems and multiple organs damage. Kidney is the main target organ for lead toxicity. Lead can cause renal glomerular damage, leading to renal interstitial fibrosis, and causing renal inflammation injury. Renal inflammation injury is current research focus, whose main mechanism is oxidative stress and cell apoptosis, etc. Preliminary study found that chronic lead exposure can cause the renal inflammation injury though increasing Methylglyoxal（MG）. MG is a dicarbonyl compounds distributed widely, with a high activity in reacting with nucleobase of DNA, RNA and residue of protein. Accumulation of MG can promote inflammatory injury through AGES-RAGE-NFκB pathway. Pu′er tea is Characteristic, it can remove MG producing by high glucose. In this study, Different doses of Pu′er tea were used to treat the lead exposure model, then detecting the whole blood lead level, inflammatory factor TNF-α, 1L-1β, RGAE protein expression and carbonyl compounds MG levels of kidney tissues of mouse. The results showed that a certain concentration of Pu′er tea can not only play pro-excretion effect, but also directly chelate the MG in organ, reduces the excessive accumulation of MG, and the formation of AGEs, down-regulate the expression of RAGE, and reduce the generation of TNF-α, 1L-1β, finally slowing subsequent inflammatory injury.