Huang M, Chen S P, Dai Y Y, Yang Y, Jiang W, Wang F, Zhang J X, Zhu Q X
Department of Occupational and Environmental Health, School of Public Health, Anhui Medical University, Hefei 230032, China.
Department of Dermatology, the Second Affiliated Hospital of Anhui Medical University, Hefei 230601, China.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi. 2021 Jan 20;39(1):5-11. doi: 10.3760/cma.j.cn121094-20200701-00380.
To observe the expressions of complement 3 (C3) and endothelial cell injury-associated proteins before and after cathepsin L (CTSL) blockade in renal injury of trichloroethylene (TCE) -sensitized mice. In June 2018, 41 SPF female BALB/c mice were divided respectively into blank control group (=5) , vehicle control group (=5) , TCE group (=15) and TCE+CTSLi group (=16) to establish trichloroethylene-sensitized mice model by pretreating the mice with intraperitoneal injection of CTSL inhibitor (CTSLi) and using TCE for the first and last challenge. According to the skin sensitization score, the mice were divided into positive group and negative group. 72 hours after the last challenge, the renal function indexes of the mice were detected, the pathological changes of mice kidneys were observed, and the glomerular C3 and endothelial cell damage-related proteins [vascular cell adhesion molecule 1 (VCAM-1) , tight junction protein 5 (Claudin-5) and Syndecan-1] expression levels were detected. The sensitization rates of mice in TCE group and TCE+CTSLi group were 53.3% (8/15) and 50.0% (8/16) , respectively, and there was no significant difference between the two groups (>0.05) . Compared with vehicle control group and the corresponding TCE negative group, the serum creatinine (CRE) and blood urea nitrogen (BUN) levels of mice in the TCE positive group was increased, while the TCE positive group were higher than the TCE+CTSLi positive group (<0.05) . Pathological examination showed obvious vacuolar degeneration and cellular edema in the mice kidney of the TCE positive group. In the TCE+CTSLi positive group, the above pathological damage was significantly improved. Immunohistochemical results showed that the expression of glomerular C3 fragment and VCAM-1 in TCE positive group were significantly higher than that of the vehicle control and TCE negative group (<0.05) , while TCE+CTSLi positive group was significantly lower than that of TCE positive group (<0.05) . Western blot test results showed that the relative expression levels of Claudin-5 and Syndecan-1 protein in the mice glomeruli of TCE positive group were significantly lower than those in the vehicle control group and TCE negative group (<0.05) . Compared with the TCE positive group, the Claudin-5 protein was increased in the kidney of the TCE+CTSLi positive group, but the difference was not statistically significant (>0.05) , while the Syndecan-1 protein was significantly increased in the TCE+CTSLi positive group (<0.05) . CTSL may mediate the glomerular structural damage by cutting complement C3, activating the complement system, damaging endothelial cell structural protein Syndecan-1 and overexpressing adhesion molecule VCAM-1 in TCE-sensitized mice. Inhibiting the expression of CTSL may be an effective way to protect the glomerular integrity of structure and function in pharmacology.
观察组织蛋白酶L（CTSL）阻断前后三氯乙烯（TCE）致敏小鼠肾损伤中补体3（C3）及内皮细胞损伤相关蛋白的表达情况。2018年6月，将41只SPF级雌性BALB/c小鼠分别分为空白对照组（n = 5）、溶剂对照组（n = 5）、TCE组（n = 15）和TCE + CTSL抑制剂（CTSLi）组（n = 16），通过腹腔注射CTSL抑制剂预处理小鼠，并使用TCE进行首次和末次激发，建立三氯乙烯致敏小鼠模型。根据皮肤致敏评分，将小鼠分为阳性组和阴性组。末次激发72小时后，检测小鼠肾功能指标，观察小鼠肾脏病理变化，检测肾小球C3及内皮细胞损伤相关蛋白[血管细胞黏附分子1（VCAM - 1）、紧密连接蛋白5（Claudin - 5）和Syndecan - 1]的表达水平。TCE组和TCE + CTSLi组小鼠的致敏率分别为53.3%（8/15）和50.0%（8/16），两组间差异无统计学意义（P>0.05）。与溶剂对照组及相应的TCE阴性组相比，TCE阳性组小鼠血清肌酐（CRE）和血尿素氮（BUN）水平升高，且TCE阳性组高于TCE + CTSLi阳性组（P<0.05）。病理检查显示，TCE阳性组小鼠肾脏有明显的空泡变性和细胞水肿。在TCE + CTSLi阳性组，上述病理损伤明显改善。免疫组化结果显示，TCE阳性组肾小球C3片段和VCAM - 1的表达明显高于溶剂对照组和TCE阴性组（P<0.05），而TCE + CTSLi阳性组明显低于TCE阳性组（P<0.05）。蛋白质免疫印迹试验结果显示,TCE阳性组小鼠肾小球中Claudin - 5和Syndecan - 1蛋白的相对表达水平明显低于溶剂对照组和TCE阴性组（P<0.05）。与TCE阳性组相比，TCE + CTSLi阳性组肾脏中Claudin - 5蛋白有所增加，但差异无统计学意义（P>0.05），而TCE + CTSLi阳性组中Syndecan - 1蛋白明显增加（P<0.05）。CTSL可能通过切割补体C3、激活补体系统、损伤内皮细胞结构蛋白Syndecan - 1和使黏附分子VCAM - 1过表达，介导TCE致敏小鼠的肾小球结构损伤。抑制CTSL的表达可能是药理学上保护肾小球结构和功能完整性的有效途径。
