血红素氧合酶1通过影响脓毒症大鼠血栓调节蛋白表达发挥肾脏保护作用

Heme oxygenase-1 protects renal function in septic rats via influencing expression of thrombomodulin

目的:探讨血红素氧合酶1(HO-1)对脓毒症大鼠肾脏的保护作用及其机制,观察肾脏血栓调节蛋白(TM)表达的变化以及HO-1对TM的影响。方法:采用盲肠结扎穿孔(CLP)法制作脓毒症大鼠模型。将72只脓毒症大鼠随机分为对照组、CLP组、CLP+HO-1诱导剂组和CLP+HO-1抑制剂组,每组18只;按分组处理后分时相处死大鼠,留取血浆和肾脏组织,分析各组之间血清肌酐(Cr)、胱抑素C(Cys-C)、碳氧血红蛋白(COHb)、凝血酶原时间(PT)和活化部分凝血活酶时间(APTT)的差别,ELISA法检测血浆TM、肿瘤坏死因子α(TNF-α)和白细胞介素1β(IL-1β)水平变化,肾脏组织经马休黄/猩红/天青石蓝染色(MSB)法对比各组之间病理变化,并应用Western blot分析肾脏组织TM表达水平。结果:与对照组相比,脓毒症组中大鼠肾脏微血栓形成明显,凝血功能障碍,炎症反应明显,肾脏功能受损;在HO-1诱导剂组中大鼠肾脏微血栓及炎症反应较脓毒症组显著减轻(P<0.05),肾脏功能得到改善,TM表达较脓毒症组上调(P<0.05);而HO-1抑制剂起到了相反的作用。结论:HO-1能够增加脓毒症大鼠肾脏TM的表达,发挥抗凝血及抗炎作用,从而改善脓毒症大鼠的肾脏功能。

AIM: To investigate the protective effect of heme oxygenase-1(HO-1) on the kidney of septic rats and the influence of HO-1 on the expression of thrombomodulin(TM) in the kidney. METHODS: Sepsis in rats was developed with cecal ligation and puncture(CLP). The septic rats were randomly divided into sham group, CLP group, CLP+HO-1 inducer group and CLP+HO-1 inhibitor group(n=18). The plasma levels of creatinine(Cr), cystatin-C(Cys-C), carboxyhemoglobin(COHb), tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β) and TM, and the changes of prothrombin time(PT) and activated partial thromboplastin time(APTT) in each group were measured. Histopathological examination was performed in the kidney. The expression of TM in the kidney tissue was detected by Western blot. RESULTS: Compared with sham group, significantly elevated plasma levels of Cr, Cys-C, TNF-α, IL-1β and TM(P<0.05), shortened PT and APTT(P<0.05), significantly increased microthrombus formation, and lowered TM expression in the kidney(P<0.05) of CLP group were observed. The administration of hemin lowered the plasma levels of Cr, Cys-C, TNF-α, IL-1β and TM(P<0.05), prolonged PT and APTT(P<0.05), attenuated microthrombus formation, and up-regulated the expression of TM in the kidney(P<0.05). In contrast, ZnPP had the opposite effects. CONCLUSION: HO-1 increases the expression of TM in the kidney and exerts anticoagulatory and antiinflammatory effects, thereby improving renal function in the septic rats.