参芍口服液对糖尿病肾病大鼠肾脏内质网应激因子GRP78、PERK及CHOP表达的影响

Effect of Shenshao oral liquid on expression of GRP78, PERK and CHOP in rat models of diabetic nephropathy

摘要:

目的观察参芍口服液对糖尿病肾病大鼠肾脏内质网应激标志性因子GRP78、PERK 及CHOP 表达的影响。方法将30只健康雄性Wistar大鼠随机分为正常对照组（Sham 组）、模型组（DN 组）和参芍口服液组（SS 组）。DN组和SS 组予以高脂饲料加链脲佐菌素腹腔注射复制糖尿病肾病模型。SS 组每日1 次给予参芍口服液（250 mg/kg）灌胃，Sham 组和DN 组每日1 次给予等剂量的蒸馏水灌胃。12 周后检测各组血糖、尿素氮（BUN）、肌酐（Scr）及24 h尿蛋白定量（PRO）；HE染色光镜下观察大鼠肾组织病理形态学改变；Western blot检测大鼠肾组织GRP78、PERK 及CHOP 蛋白表达情况；TUNEL 染色检测大鼠肾组织细胞凋亡情况。结果DN组血糖、BUN、Scr及PRO与Sham组相比均增高，SS组血糖、BUN、Scr及PRO 与DN组相比均降低（P <0.05）。HE发现Sham 组大鼠肾组织形态结构清楚，未见异常；DN 组可见肾小球体积增大，可见大量炎症细胞浸润，肾小球系膜基质区增生，肾小管基底膜增厚，部分肾小球、肾小管出现纤维化；SS 组肾组织病理形态变化轻于DN组。Western blot发现DN组肾脏组织GRP78、PERK 及CHOP 蛋白表达高于Sham 组，SS 组肾组织GRP78、PERK 及CHOP 蛋白表达均低于DN 组（P <0.05）。TUNEL发现DN组较Sham 组肾脏组织存在更多细胞凋亡；SS 组凋亡细胞少于DN组。结论参芍口服液可减轻糖尿病肾病大鼠肾脏病理损害，延缓肾功能减退，具有肾保护作用，其机制可能与降低内质网应激相关因子GRP78、PERK 及CHOP的表达及减少肾组织细胞凋亡有关。

Abstract:

Objective To investigate the effect of Shenshao oral liquid on expression of endoplasmic reticulum stress factors GRP78, PERK and CHOP in rat models of diabetic nephropathy. Methods A total of 30 healthy male Wistar rats were randomly divided into Sham group, model group (DN group) and Shenshao oral liquid group (SS group). Animals in DN group and SS group were fed with high fat diet in addition to intraperitoneal injection of streptozotocin. Rats in SS group were administrated with Shenshao oral liquid (250 mg/kg) daily, and distilled water were administered daily into rats from Sham group and DN group. Blood glucose, blood urea nitrogen (BUN), creatinine (Scr) and 24-hour urinary protein (PRO) were measured 12 weeks post insults. Histopathological changes in renal tissue were graded through HE staining. Expression levels of GRP78, PERK and CHOP in kidney were measured by Western blot. Apoptosis rate were determined by TUNEL staining. Results Blood glucose, BUN, Scr and PRO in rats from DN group were significantly increased compared with Sham group (P < 0.05), which were attenuated with treatment of Shenshao oral liquid (P < 0.05). HE staining showed that morphological abnormality was observed in DN group including enlarged glomerular volume, inflammatory cell infiltration, glomerular mesangial stromal hyperplasia, tubular basement membrane thickening, and glomerular and tubular fibrosis. Above histopathological deterioration of renal tissue was significantly ameliorated by treatment of Shenshao oral liquid (P < 0.05). Western blot showed that the expression levels of GRP78, PERK and CHOP in renal tissue of DN group were significantly increased when compared with Sham group, which was decreased in SS group. TUNEL staining manifested that increased apoptosis rate in DN group ( < 0.05) in comparison with Sham group could be attenuated in SS group (P <0.05). Conclusions Shenshao oral liquid reduces development of diabetic nephropathy, restoring renal function in dependence of manipulation on endoplasmic reticulum stress related factors GRP78, PERK, CHOP and apoptosis.