摘要
目的探讨内质网应激(ERS)诱导的肾小管上皮细胞凋亡是否参与了横纹肌溶解肾损伤过程。方法雄性Wistar大鼠33只,根据标本采集时间分为对照组及模型组,后者又按照时间分为1、3、6、12、24、48、72、96、120、168h 10个亚组(n=3)。建立甘油诱导横纹肌溶解肾损伤大鼠模型,建模后于相应时间点分别处死大鼠,收集血清及肾脏组织,利用肾功能指标和肾组织病理评估不同时间点肾脏损伤程度;采用TUNEL染色评估肾小管上皮细胞凋亡程度;Western blotting检测死亡受体途径和线粒体凋亡途径关键凋亡因子caspase-8、细胞色素C及caspase-9活性片段的表达,同时检测ERS伴侣蛋白GRP-78和特异性内质网凋亡因子caspase-12活性片段的表达。结果横纹肌溶解肾损伤后1h肾小管上皮细胞出现病变,24h出现大量坏死、脱落,肾小管上皮细胞凋亡数最高,72h肾小管-间质损伤达高峰。横纹肌溶解肾损伤后凋亡因子caspase-8、细胞色素C和caspase-9的表达上调,12h达到高峰(P<0.05),GRP-78表达升高趋势与caspase-12一致。结论肾小管上皮细胞凋亡是横纹肌溶解肾损伤的主要发病机制,除了死亡受体及线粒体途径的活化,ERS也可能在此过程中发挥了重要作用。
Objective To investigate whether apoptosis of renal tubular epithelial cells induced by endoplasmic reticulum stress （ERS） takes a role in the traumatic rhabdomyolysis-induced acute kidney injury （AKI）. Methods The model of rhabdomyolysis-induced AKI was reproduced by intramuscular injection of hypertonic glycerol into the hind limbs in male Wistar rats. There were 11 animal groups （each n=3） including control, lh, 3h, 6h, 12h, 24h, 48h, 72h, 96h, 120h and 168h groups. Serum and renal tissue were collected at various time points. Parameters of renal function and renal pathology were used to evaluate renal injury at various time points. The renal tubular epithelial cell apoptosis was revealed by TUNEL staining at each time point. The expressions of factors, caspase-8, cytochrome C and caspase-9 activity fragments, involved in apoptosis as induced by Fas ligand/ receptor interaction and mitochondria were determined by Western blotting at each time point. Furthermore, the expressions of endoplasmic reticulum chaperone protein GRP78 and apoptosis factor caspase-12 activity fragment were also assayed by Western blotting. Results Pathological changes of tubular epithelial cells were detected at lh, presenting a large area of necrosis at 24h, with the highest number of apoptotic renal tubular epithelial cells. Tubular-interstitial injury reached the peak at 72h. The expression of apoptotic factors （caspase-8, cytochrome C and caspase-9） was elevated reaching the peak at 12h. The change in endoplasmic reticulum stress protein expressions of GRP-78 showed a similar trend as that of caspase-12 （increased at lh, and reached the peak at 12h）. Conclusions Apoptosis of renal tubular epithelial cell is the main pathogenesis of rhabdomyolysis-induced renal injury. In addition to the activation of the death-receptor and the mitochondrial death pathway, endoplasmic reticulum stress also plays an important role in this process.
出处
《解放军医学杂志》
CAS
CSCD
北大核心
2015年第3期194-199,共6页
Medical Journal of Chinese People's Liberation Army
基金
全军医学科技青年培育项目(13QNP180)
国家自然科学基金(81470949)
北京市科技新星计划(Z121107002512078)
国家支撑计划课题(2011BAI10B00)
国家973项目(2013CB530800)~~
关键词
横纹肌溶解
急性肾损伤
细胞凋亡
内质网应激
rhabdomyolysis, acute kidney injury, apoptosis, endoplasmic reticulum stress
