香叶木素缓解MRL/lpr狼疮性肾炎小鼠肾炎症反应的作用及可能机制

Role and possible mechanism of diosmetin in alleviating nephritis response in MRL/lpr lupus nephritis mice

目的 探讨香叶木素对狼疮性肾炎的保护作用及其可能的机制。方法 将10只C57BL/6小鼠作为对照组,50只MRL/lpr狼疮性肾炎小鼠按随机数字表法分为MRL/lpr组、地塞米松组、香叶木素低剂量组(0.25 mg/kg)、香叶木素中剂量组(0.50 mg/kg)和香叶木素高剂量组(1.00 mg/kg),每组10只。连续7 d腹腔注射给药,取所有小鼠血清及肾脏组织。HE染色观察肾组织形态学变化。试剂盒检测血清肌酐、血尿素氮和血清抗双链DNA抗体水平,以及血清和肾组织中IL-1β、IL-6和TNF-α表达水平。Western blot检测肾组织中NLRP3、ASC、Caspase-1、IL-1β、p-NF-κB和p-IκBα蛋白表达。结果 与MRL/lpr组相比,香叶木素中、高剂量组和地塞米松组小鼠肾组织中炎性细胞浸润减少,且小鼠血清肌酐、血尿素氮和血清抗双链DNA抗体的水平均显著降低(P<0.05),小鼠血清和肾脏组织中IL-1β、IL-6和TNF-α的蛋白表达均显著降低(P<0.05)。与MRL/Lpr组相比,香叶木素中、高剂量组和地塞米松组小鼠肾组织中NLRP3、ASC、Caspase-1、IL-1β和p-NF-κB的蛋白表达均显著降低(P<0.05),而p-IκBα蛋白表达显著升高(P<0.05)。结论 香叶木素对MRL/lpr小鼠肾脏具有一定保护作用,其机制可能与抑制NLRP3和NF-κB信号通路有关。

Objective To investigate the protective effect of diosmetin on lupus nephritis and its possible mechanism. Methods Ten C57 BL/6 mice were used as control group, and 50 MRL/lpr lupus mice were randomly divided into MRL/lpr group, dexamethasone group, and 3 doses of diosmetin groups(0.25, 0.50 and 1.00 mg/kg). After intraperitoneal injection for 7 d, the serum and kidney tissues of all mice were collected. HE staining was used to observe the morphological changes of the kidneys. Corresponding kits were used to measure the levels of serum creatinine, blood urea nitrogen, and serum anti-double-stranded DNA antibody, as well as the expression levels of IL-1β, IL-6, and TNF-α in the serum and renal tissue. The protein levels of NLRP3, ASC, Caspase-1, IL-1β, p-NF-κB and p-IκBα in renal tissues were detected by Western blotting. Results Compared with the MRL/lpr group, the medium and high dose diosmetin groups and the dexamethasone group had reduced infiltration of inflammatory cells in the kidney tissue, and significantly decreased levels of serum creatinine, blood urea nitrogen and serum anti-double-chain DNA antibody(P<0.05). Meanwhile, the protein expression levels of IL-1β, IL-6 and TNF-α in the serum and kidney tissues were also significantly decreased(P<0.05). Compared with the MRL/lpr group, the protein levels of NLRP3, ASC, Caspase-1, IL-1β and p-NF-κB were remarkably decreased(P<0.05), while that of p-IκBα was notably increased in the medium and high dose diosemetin groups and the dexamethasone group(P<0.05). Conclusion Diosmetin has a protective effect on the kidney of MRL/lpr mice, and the mechanism may be related to the inhibition of NLRP3 and NF-κB signaling pathway.