[Animal modeling] Effect of low expression of lipoic acid synthase on antioxidant capacity of mice

  Objective To establish a genetically modified mouse with low expression of lipoic acid synthase gene and detect its antioxidant capacity.

  Methods The Loxp mice in the 3 '- UTR region of lipoic acid synthase gene were hybridized with E2a Cre mice, and the LiasL/+mice were identified from the offspring mice, and further reproduction and genotype identification were conducted. Ten 8-week old male mice with LiasL/L and Lias+/+genotypes were selected; After weighing and anesthesia, blood was collected through femoral artery, and then lungs, kidneys and livers of mice were separated and weighed. The expression of lipoic acid synthase (LIAS) protein in lung, kidney and liver tissues was detected by Western Blot and immunohistochemistry; Serum was separated and total antioxidant capacity (TAC) was measured; The total protein was extracted from kidney, liver and lung homogenates, and the activity of SOD, CAT enzyme and the content of MDA were detected.

  Results Western Blot and immunohistochemical analysis showed that except the results of liver LIAS immunohistochemical analysis, the expression level of Lias protein in kidney, liver and lung tissues of LiasL/L group mice was significantly lower than that of LIAS+/+group mice (P<0.05). Compared with Lias+/+group mice, the serum TAC level of LiasL/L group mice decreased significantly (P<0.05), the SOD and CAT enzyme activities in kidney, liver and lung organs of LiasL/L mice decreased significantly, and the MDA level increased significantly (P<0.05).

  Conclusion The gene modified mice with low expression of lipoic acid synthase gene were identified in this study. The expression of lipoic acid synthase gene in kidney, liver and lung was lower than that in wild-type mice, and caused oxidative damage to corresponding organs.