Chito-oligosaccharides, the novel marine functional oligosaccharides, possess broad activities including anti-inflammatory and anti-oxidative effects. However, there are few studies about the molecular mechanisms of chito-oligosaccharides monomers against oxidative stress. In this study, the anti-oxidative effect and mechanism of Chitopentaose hydrochloride (COS-5) were explored in HaCaT cells. The results indicated that COS-5 improved cell viability and decreased the production of ROS induced by hydrogen peroxide (H₂O₂). COS-5 can increase the antioxidant-related enzymes including SOD and CAT and can reduce MDA production and LDH leakage in HaCaT cells. COS-5 effectively inhibited the decline of MMP and the expression of Caspase-3 protein. Moreover, COS-5 can significantly down-regulate abnormal activation of MAPKs pathway and up-regulate the Nrf2/ARE pathway. In summary, COS-5 has significant protective effect against H₂O₂-induced oxidative stress in HaCaT cells through regulating MAPKs and Nrf2/ARE pathways, suggesting that COS-5 may be used as a novel functional food supplement to prevent oxidative-stress-related diseases in the future.

壳寡糖是一种新型的海洋功能性寡糖，具有广泛的活性，包括抗炎和抗氧化作用。然而，关于壳寡糖单体抗氧化应激的分子机理的研究很少。在这项研究中，探讨了HaCaT细胞中盐酸几丁质糖（COS-5）的抗氧化作用及其机理。结果表明，COS-5可提高细胞活力，并降低过氧化氢（H ₂ O ₂）。COS-5可以增加抗氧化剂相关的酶，包括SOD和CAT，并可以减少HaCaT细胞中MDA的产生和LDH的泄漏。COS-5有效抑制MMP的下降和Caspase-3蛋白的表达。此外，COS-5可以显着下调MAPKs途径的异常激活并上调Nrf2 / ARE途径。总之，COS-5通过调节MAPK和Nrf2 / ARE途径对HaCaT细胞中H ₂ O ₂引起的氧化应激具有显着的保护作用，这表明COS-5可以用作预防氧化应激的新型功能性食品补充剂。相关疾病。