Protective effects of whey protein isolate (wpi) peptides on lung fibroblasts cell mrc-5 caused by the damage of h2o2 | 乳清蛋白抗氧化肽对H2O2所致人胚肺成纤维细胞MRC-5过氧化损伤的保护作用

صينى. 【目的】探讨纯化后的乳清蛋白抗氧化肽P4对人胚肺成纤维细胞(human lung fibroblast)MRC-5过氧化损伤的保护作用及可能的作用机制。【方法】采用H2O2诱导建立细胞氧化损伤模型,应用四唑蓝快速比色法(MTT法)检测细胞存活率,通过检测细胞培养液中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)活性及丙二醛(MDA)含量,来确定P4对过氧化损伤MRC-5细胞的保护作用,并利用电镜观察细胞形态学变化。【结果】1 mmol?L-1 H2O2孵育24 h可显著诱导MRC-5细胞损伤,使细胞存活力下降到22.47%,细胞经不同浓度的抗氧化肽P4(4、20、100 μg?mL-1)与H2O2共孵育后,特别是100 μg?mL-1(高剂量组)抗氧化肽P4可使细胞存活率达到44.77%。同时,提高乳清蛋白抗氧化肽P4的浓度,可促进受损的MRC-5细胞修复,提高了SOD、CAT、GSH-Px酶活性,降低MDA含量。扫描电镜和透射电镜观察结果也表明,一定浓度的乳清抗氧化肽对MRC-5细胞具有保护作用。【结论】乳清抗氧化肽通过拮抗H2O2而对MRC-5的过氧化损伤具有保护作用。

إنجليزي. 【Objective】 A study was conducted to investigate the protective effects of purified whey protein isolate (WPI) peptides P4 on lung fibroblasts cell MRC-5 caused by the damage of H2O2 and its protective mechanism. 【Method】 Oxidative damage was induced by H2O2, and cell viability was measured by the 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay. The influence of WPI peptides P4 on H2O2-induced MRC-5 injury was assessed by measuring the superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities and the malondialdehyde (MDA) content. The change of cell morphology was observed by scanning transmission electron microscopy. 【Result】 The results demonstrated that MRC-5 cells were damaged by incubation with 1 mmol?L-1 H2O2 for 24 h, and the viability of MRC-5 cells reduced to 22.47%. The addition of WPI peptides P4 (4, 20, and 100 μg?mL-1) into the MRC-5 cell suspensions prior to the exposure to 1 mmol?L-1 of H2O2 resulted in a greater survival rate of the cells. In particular, the cell viability reached 44.77% after treating with 100 μg?mL-1 WPI peptides P4. Moreover, at elevated concentrations, WPI peptides P4 exhibited increased repairing capability for injured MRC-5 as well as increased protection of SOD, CAT and GSH-PX while reducing MDA formation. Scanning transmission electron microscopy also showed that WPI peptides P4 had the protection on MRC-5. 【Conclusion】 The purified WPI peptides P4 possess protective effects on MRC-5 cell injuries induced by H2O2, and this may be related to the antioxidative activity of WPI peptides.