基于PGC-1α通路探索珍龙醒脑胶囊对大鼠脑缺血再灌注损伤的保护机制

Exploring the Protective Mechanism of Zhenlong Xingnao Capsule on Cer ebral Ischemia-reperfusion Injury in Rats based on PGC-1αPathway

目的:基于过氧化物酶体增殖物激活受体-γ共激活因子-1α(PGC-1α)通路探索珍龙醒脑胶囊对大鼠脑缺血再灌注损伤的保护机制。方法:SD大鼠随机分为假手术组(Sham)组、模型组(I/R)组、珍龙醒脑低、中、高剂量组(ZLXNl、ZLXNm、ZLXNh)组。每组12只。除Sham外采用改良的Longa 法复制缺血性脑损伤大鼠模型,造模后除I/R外,3组大鼠分别灌胃给予珍龙醒脑50、100及200mg/(kg·d),I/R组和Sham组同步给予0.9%氯化钠溶液,疗程1周。造模后第6,12,24h进行神经功能缺陷评分;治疗干预1周后采用ELISA法检测海马组织中超氧化物歧化酶(SOD)、丙二醛、谷胱甘肽过氧化物酶、肿瘤坏死因子-α、白细胞介素-6含量,Western blot 检测核转录因子κB(NF-κB)、PGC-1α、核呼吸因子-1(NRF1)、线粒体转录因子 A(TFAM)的mRNA表达。结果:与I/R组比较,ZLXNm、ZLXNh组各时间点神经功能缺陷评分明显降低,差异具有统计学意义(P<0.05);珍龙醒脑胶囊各剂量组的 白细胞介素-6、肿瘤坏死因子-α和丙二醛水平显著降低,而谷胱甘肽过氧化物酶显著升高,差异有统计学意义(P< 0.05)。ZLXNl组SOD活性与I/R组比较,差异无统计学意义(P>0.05),ZLXNm、ZLXNh组SOD显著升高,差异有统计学意义(P<0.05)。珍龙醒脑各剂量组海马组织PGC-1α和 TFAMmRNA 表达显著升高(P<0.05),NF-κB蛋白表达在ZLXNm、ZLXNh组显著降低(P<0.05),NRF1蛋白表达在ZLXNm、ZLXNh组显著升高(P<0.05)。结论:珍龙醒脑胶囊可以促进脑缺血再灌注损伤大鼠的神经功能恢复,并抑制氧化应激和炎性反应从而发挥神经保护作用。其机制可能与 NF-κB表达的下调和 PGC-1α 信号通路激活有关。

Objective:To explore the protective mechanism of Zhenlong Xingnao Capsule on cerebral ischemia-reperfusion injury in rats based on the peroxisome proliferator-activated receptor-γcoactivator-1α(PGC-1α)pathway.Methods:SD rats were randomly divided into sham operation group(Sham),model group(I/R),Zhenlong Xingnao low,medium and high dose groups(ZLXNl,ZLXNm,ZLXNh).There were 12 rats in each group.Except for Sham,the modified Longa method was used to replicate the rat model of ischemic brain injury.After modeling,except for I/R,the three groups of rats were given Zhenlong Xingnao 50,100 and 200 mg/(kg·d)by gavage,and the I/R group and Sham group were given 0.9%sodium chloride solution simultaneously.The treatment course was 1 week.Neurological deficit scores were performed at 6,12,and 24 hours after modeling.After one week of treatment,ELISA was used to detect the levels of superoxide dismutase(SOD),malondialdehyde,glutathione peroxidase,tumor necrosis factor-α,and interleukin-6 in hippocampal tissue,and Western blot was used to detect the mRNA expressions of nuclear transcription factorκB(NF-κB),PGC-1α,nuclear respiratory factor-1(NRF1),and mitochondrial transcription factor A(TFAM).Results:Compared with the I/R group,the neurological deficit scores of the ZLXNm and ZLXNh groups at each time point were significantly reduced,and the differences were statistically significant(P<0.05);the levels of interleukin-6,tumor necrosis factor-α,and malondialdehyde in the Zhenlong Xingnao Capsule groups were significantly reduced,while the levels of glutathione peroxidase were significantly increased,and the differences were statistically significant(P<0.05).There was no significant difference in SOD activity between the ZLXNl group and the I/R group(P>0.05),while SOD in the ZLXNm and ZLXNh groups increased significantly(P<0.05).The expression of PGC-1αand TFAM mRNA in the hippocampus of each dose group of Zhenlong Xingnao was significantly increased(P<0.05),the expression of NF-κB protein was significantly decreased in the ZLXNm and ZLXNh groups(P<0.05),and the expression of NRF1 protein was significantly increased in the ZLXNm and ZLXNh groups(P<0.05).Conclusion:Zhenlong Xingnao Capsule can promote the recovery of neurological function in rats with cerebral ischemia-reperfusion injury,and inhibit oxidative stress and inflammatory response to play a neuroprotective role.Its mechanism may be related to the downregulation of NF-κB expression and the activation of PGC-1αsignaling pathway.