Objective To establish a genetically modified mouse with low expression of lipoic acid synthase gene, and to test its antioxidant capacity.
METHODS: Loxp mice in the 3'-UTR region of lipoic acid synthase gene were crossed with E2a-Cre mice, and LiasL/+ mice were identified from the offspring, and further bred and genotyped. Ten 8-week-old male mice with genotypes of LiasL/L and Lias+/+ were selected; they were weighed and anesthetized, and blood was collected from the femoral artery, and then the lungs, kidneys and livers of the mice were isolated and weighed. The expression levels of lipoic acid synthase (LIAS) protein in lung, kidney and liver tissues were detected by Western Blot and immunohistochemical methods; serum was separated to detect total antioxidant capacity (TAC); kidney, liver and lung were homogenized and extracted. Total protein, SOD, CAT enzyme activity and MDA content were detected.
Results Western Blot and immunohistochemical analysis showed that, in addition to the results of LIAS immunohistochemical analysis of mouse liver, the expression levels of LIAS protein in kidney, liver and lung tissues of LiasL/L group mice were significantly lower than those of Lias+/+ group mice ( P < 0.05). Compared with Lias+/+ group mice, the serum TAC level of LiasL/L group mice was significantly decreased (P < 0.05), the activities of SOD and CAT enzymes in kidney, liver and lung organs of LiasL/L mice were significantly decreased, and MDA was significantly decreased. levels were significantly increased (P < 0.05).
Conclusion In this study, genetically modified mice with low expression of lipoic acid synthase gene were identified, and their expression in kidney, liver and lung was lower than that of wild-type mice, and caused oxidative damage to the corresponding organs.