槲皮素对急性脑出血大鼠神经功能恢复的作用及对PKC/ERK信号通路的影响

Effect of quercetin on recovery of neurological function and PKC/ERK signaling pathway in rats with acute cerebral hemorrhage

目的探讨槲皮素对急性脑出血大鼠神经功能恢复的作用及对蛋白激酶C(PKC)/胞外信号调节蛋白激酶(ERK)信号通路的影响。方法50只SD雄性大鼠随机取10只作为A组,34只急性脑出血模型大鼠随机分为B组、C组、D组、E组,分别纳入8只、8只、9只、9只。B组、D组、E组分别以含10μL/kg PKC激动剂佛波醇酯、75 mg/kg槲皮素+10μL/kg PKC激动剂佛波醇酯混合液、75 mg/kg槲皮素的生理盐水1 mL腹腔注射,A组、C组以1 mL生理盐水腹腔注射,每隔12 h给药1次,连续3 d。采用神经功能缺陷评分(NSS)评估神经功能;干湿法测定脑组织湿重/干重(W/D)值;酶联免疫吸附法(ELISA)检测白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α);原位末端脱氧核苷酸转移酶标记(TUNEL)法评估神经细胞凋亡;苏木精-伊红(HE)染色法检测脑组织病理形态学;蛋白质印迹法检测PKC、磷酸化PKC(p-PKC)、ERK1/2、磷酸化ERK1/2(p-ERK1/2)蛋白相对表达量。结果与B组比较,C组、D组、E组NSS评分降低,且E组<D组<C组(P<0.05);与A组比较,B组、C组、D组、E组W/D、IL-6、TNF-α、神经细胞凋亡率升高,且E组<D组<C组<B组(P<0.05);HE染色显示,与B组、C组比较,D组、E组神经细胞结构、神经元数目、细胞核等形态异常有所改善,其中E组改善更显著;与A组比较,B组、C组、D组、E组p-PKC、p-ERK1/2蛋白相对表达量升高,且E组<D组<C组<B组(P<0.05)。结论槲皮素可促进急性脑出血大鼠神经功能恢复,作用机制可能与调节PKC/ERK信号通路有关。

Objective To investigate the effect of quercetin on the recovery of neurological function and the protein kinase C(PKC)/extracellular-regulated kinase(ERK)signaling pathway in rats with acute cerebral hemorrhage.Methods 10 male SD rates were randomly selected from 50 SD male rats were randomly selected as group A,34 acute cerebral hemorrhage model rats were randomly divided into group B,group C,group D,and group E,including 8,8,9,and 9 rats respectively.Group B,group D and group E were injected intraperitoneally with 1 mL normal saline containing 10μL/kg PKC agonist phorbol ester,75 mg/kg quercetin+10μL/kg PKC agonist phorbol ester mixture and 75 mg/kg quercetin respectively.Group A and group C were injected intraperitoneally with 1 mL normal saline every 12 hours for 3 consecutive days.Neurological severity scores(NSS)was used to evaluate neurological function.Wet/dry weight ratio(W/D)of brain tissue was measured by wet and dry methods.Interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)were detected by enzyme linked immunosorbent assay(ELISA).In situ terminal deoxynucleoitidy transferase mediated nick end labeling(TUNEL)was used to evaluate neuronal apoptosis.Hematoxylin eosin(HE)staining was used to detect brain histopathology.The relative protein expression of PKC,p-PKC,ERK1/2 and p-ERK1/2 were detected by Western blot.Results Compared with group B,the NSS scores of group C,group D and group E decreased,group E<group D<group C(P<0.05).Compared with group A,W/D,IL-6,TNF-αand apoptosis rate of nerve cells in group B,group C,group D and group E increased,group E<group D<group C<group B(P<0.05).HE staining showed that compared with group B and group C,the morphological abnormalities of nerve cell structure,neuron number and nucleus in group D and group E were improved,especially in group E.Compared with group A,the relative expression levels of p-PKC and p-ERK1/2 protein in group B,group C,group D and group E were increased,group E<group D<group C<group B(P<0.05).Conclusions Quercetin can promote the recovery of neurological function in rats with acute intracerebral hemorrhage,and its mechanism may be related to the regulation of PKC/ERK signaling pathway.