海洋多肽对血管内皮细胞氧化损伤保护作用及机制

PROTECTIVE EFFECT AND MECHANISM OF POLYPEPTIDE FROM POLLOCK SKIN AGAINST OXIDATIVE INJURY IN VASCULAR ENDOTHELIAL CELLS

目的观察狭鳕鱼皮多肽对H2O2诱导的血管内皮细胞氧化损伤的保护作用及机制。方法制备H2O2诱导的人脐静脉内皮细胞(HUVECs)氧化损伤模型。实验分为正常对照组、模型组以及狭鳕鱼皮多肽高、中、低等3个剂量预处理组。狭鳕鱼皮多肽各剂量组应用多肽预处理6 h后,除正常对照组以外,其余各组细胞培养液中均加入H2O2,37℃孵育12 h。应用CCK-8方法检测细胞活性,酶法测定细胞抗氧化活性,流式细胞术检测细胞的凋亡情况,Western blot方法测定Caspase-3、P53及Bax/Bcl-2的表达。结果与正常对照组比较,模型组HUVECs增殖活性下降,抗氧化能力显著降低,凋亡率升高;与模型组比较,狭鳕鱼皮多肽高、中剂量组细胞增殖活性显著增加,抗氧化能力显著恢复,凋亡细胞减少,差异有显著性(F=4.71~56.90,P<0.05)。Western blot分析显示,狭鳕鱼皮多肽预处理可抑制Caspase-3的活化,下调P53表达,降低Bax/Bcl-2比值,显著降低H2O2介导的HUVECs凋亡(F=37.30~1508.00,P<0.05)。结论狭鳕鱼皮多肽对H2O2诱导的血管内皮细胞氧化损伤具有明显的保护作用,其作用与狭鳕鱼皮多肽显著提高内皮细胞的抗氧化能力,下调P53表达,抑制Caspase-3活化并降低Bax/Bcl-2比值,降低细胞凋亡有关。

Objective To investigate the protective effect and mechanism of pollock skin polypeptide against oxidative injury in vascular endothelial cells induced by H2O2.Methods Human umbilical vein endothelial cells(HUVECs)were used to establish a model of H2O2-induced oxidative injury,and the experimental cells were divided into normal control group,model group,and high-,middle-,and low-dose pollock skin polypeptide groups.The high-,middle-,and low-dose pollock skin polypeptide groups were pretreated with polypeptide for 6 h,and then all groups except the normal control group were cultured with H2O2 for 12 h at 37℃.CCK-8 assay was used to evaluate cell viability,the enzymatic method was used to measure the antioxidant activities of cells,flow cytometry was used to measure apoptosis rate,and Western blot was used to measure the expression of Caspase-3,P53,and Bcl-2-associated X(Bax)/B-cell lymphoma-2(Bcl-2).Results Compared with the normal control group,the model group had significant reductions in proliferative activity and antioxidant capacity and a significant increase in apoptosis rate.Compared with the model group,the high-and middle-dose pollock skin polypeptide groups had a significant increase in proli-ferative activity,a significant recovery of antioxidant capacity,and a significant reduction in cell apoptosis(F=4.71-56.90,P<0.05).Western blot showed that pretreatment with pollock skin polypeptide inhibited the activation of Caspase-3,downregulated the expression of P53,and reduced Bax/Bcl-2 ratio and the apoptosis of HUVECs due to H2O2(F=37.30-1508.00,P<0.05).Conclusion Pollock skin polypeptide exerts a marked protective effect against H2O2-induced oxidative injury in vascular endothe-lial cells,possibly by increasing the antioxidant capacity of vascular endothelial cells,downregulating P53,inhibiting the activation of caspase-3,and reducing Bax/Bcl-2 ratio and cell apoptosis.