二乙烯三胺/一氧化氮聚合物诱导的驴乳腺上皮细胞氧化损伤模型的建立OA

This experiment aimed to investigate the conditions for inducing oxidative damage in donkey mam-mary epithelial cells(DMECs)using diethylenetriamine/nitric oxide polymer(DETA/NO),in order to estab-lish a reliable cellular oxidative damage model for research related to donkey mammary glands.In experiment 1,F2 generation DMECs cultured in vitro were treated with varying concentrations(0,200,400,600,800,1 000 and 1 200 μmol/L)of DETA/NO as a stressor for 2,4,6 and 8 h to simulate an oxidative damage environment caused by excessive nitric oxide(NO)accumulation in vivo,and to identify the suitable DETA/NO treatment time based on the cell proliferation rate.In experiment 2:based on the suitable DETA/NO treatment time(6 h)identified in experiment 1,DMECs were treated with different concentrations(0,200,400,600,800,1 000 and 1 200 μmol/L)of DETA/NO for 6 h.Using oxidative stress and inflamma-tory response indicators as criteria,the optimal DETA/NO concentration for establishing the DMEC oxidative damage model was further determined.Additionally,to validate the successful establishment of the DETA/NO-induced oxidative damage model in DMECs,the expression of genes related to antioxidant and inflammatory factors were measured in the oxidative damaged DMECs.The results showed as follows:1)when DMECs were treated with 1 000 μmol/L DETA/NO for 6 h,the cell proliferation rate was 66.61%,which falled within the suitable range(60%to 70%)for establishing a cellular oxidative damage model.Thus,6 h was se-lected as the suitable DETA/NO treatment time.2)DETA/NO at concentrations of 800 to 1 200 μmol/L in-duced oxidative damage in DMECs compared with the control group(0 μmol/L),as indicated by significantly reduced activities of catalase(CAT),glutathione peroxidase(GPx)and superoxide dismutase(SOD)(P＜0.05),along with significantly elevated levels of the interleukin-1β(IL-1β),interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)(P＜0.05).Furthermore,compared with the 800 μmol/L group,the 1 000 and 1 200 μmol/L groups exhibited even lower activities of the aforementioned antioxidant enzymes and higher levels of inflammatory factors such as IL-1β.However,no significant differences were observed in these indicators be-tween the 1 000 and 1 200 μmol/L groups(P＞0.05).Considering that the cell proliferation rate in the 1 200 μmol/L group was relatively lower(58.6%),1 000 μmol/L was selected as the optimal DETA/NO treat-ment concentration for establishing the oxidative damage model.Validation of the DMEC oxidative damage model established by treatment with 1 000 μmol/L DETA/NO for 6 h,the results showed that the mRNA relative expres-sion levels of CAT and GPx1 in the 1 000 μmol/L group were significantly lower than those in the control group(P＜0.05),while the mRNA relative expression levels of IL-1β,IL-6 and TNF-α were significantly higher(P＜0.05).In summary,treatment with 1 000 μmol/L DETA/NO for 6 h can successfully establish an oxidative dam-age model in DMECs.[Chinese Journal of Animal Nutrition,2026,38(4):2994-3002]