摘要
目的:探讨适度活化低氧诱导因子(hypoxia-inducible factor,HIF)对延缓残肾慢性肾脏病进展的作用及可能机制。方法:雄性SD大鼠采用二步法5/6肾大部切除术建立残肾模型,随机分为L-mimosine(L-Mim)治疗组(术后5~12周短期给予脯氨酸羟化酶抑制剂,隔日50 mg/kg腹腔给药)和未治疗残肾组,同时设立假手术对照组。术后12周末处死大鼠留取标本。结果:L-Mim治疗组大鼠血肌酐水平[(82.4±6.3)比(130.1±24.1)μmol/L,P〈0.05]、24 h尿蛋白水平[(0.7±0.1)比(1.7±0.5)g/d,P〈0.05]以及残肾病理改变较未治疗残肾组大鼠有显著改善。miRNA芯片分析结果提示:L-Mim治疗组肾皮质miR-29c丰度高于未治疗残肾组,伴HIF-1α和HIF-2α表达增强。经荧光素酶报告检测系统和体外突变实验明确原肌球蛋白1(TPM1)为miR-29c靶基因之一。HK2细胞转染pre-miR-29c寡核苷酸后可以抑制TGF-β1(3 ng/mL,24 h)诱导的原肌球蛋白水平上调(P〈0.05或0.01)。结论:大鼠残肾肾间质纤维化病变明显并伴miR-29c水平下调,适度活化HIF水平可通过上调miR-29c表达延缓残肾功能恶化。
Objective:To investigate the role and probable mechanism of moderate activation of hypoxia-inducible factor(HIF)in slowing chronic kidney disease progression of remnant kidney.Methods:Rat models of remnant kidney were established by5/6 subtotal nephrectomy in male Sprague-Dawley rats.And then they were randomly allocated to L-mimosine(L-Mim)treatment group,in which the rats were treated with intraperitoneal injections of L-Mim during 5-12 week after operation,and untreated remnant kidney group.Meanwhile,sham operated rats were set as control group.All rats were sacrificed at the end of week 12,and the specimens were collected.Results:The serum creatinine level in L-Mim treatment group was lower than that in untreated remnant kidney group(82.4±6.3 vs.130.1±24.1μmol/L,P〈0.05),as well as the 24 h Ualblevel(0.7±0.1 vs.1.7±0.5 g/d,P〈0.05).And the pathological changes in in L-Mim treatment group was slightly improved while compared to untreated remnant kidney group.The result of miRNA microarray analysis showed that miR-29 c in renal cortex was up-regulated in L-Mim group compared with untreated remnant group and meanwhile the expressions of HIF-1αand HIF-2αincreased.Tropomyosin1(TPM1)met the sequence criteria for microRNA-target interaction,which was later confirmed by luciferase reporter system and mutation test in vitro.HK2 cell transfected with pre-miT-29 c oligonucleotide could inhibit the tropomyosin up-regulation induced by TGF-β1treatment(3 ng/mL,24 h),P〈0.05 or 0.01.Conclusions:Renal interstitial fibrosis in rat remnant kidney was significant,and it was accompanied by the miR-29 c down-regulation.Moderate activation of HIF level may attenuate the deterioration of renal function by up-regulating miR-29 c expression.
出处
《中国临床医学》
2016年第1期6-12,共7页
Chinese Journal of Clinical Medicine
基金
国家自然科学基金资助项目(编号:81200557
81430015)
上海市科学技术委员会基金项目(编号:14DZ2260200)