动物造模 z-bio 2022-09-24 313

　　Objective To screen the differentially expressed genes and their related pathways in rat tibialis anterior muscle from chronic intermittent hypoxia exposure and acute hypoxia exposure.

　　Methods Twenty-four SD rats were divided into normoxia control group (C group), chronic intermittent hypoxia group (IH group, the oxygen concentration was 12.4%, 8 hours a day for 4 weeks) and acute hypoxia group (AH group). group, the oxygen concentration was 12.4%, 24 hours a day, a total of 3 days). After the intervention, the grasping force and lean body mass were tested, the tibialis anterior muscle (TA) was taken for HE staining, the muscle fiber cross-sectional area (FCSA) was counted, and the protein relative contents of Atrogin-1 and MuRF1 were tested by Western Blot, and the rats were extracted. TA total RNA was sequenced, the differential genes were screened, and the related biological process (BP) and pathway (pathway) were analyzed.

　　Results (1) During the intervention, the body weight of the IH group was lower than that of the C group at each time point, and the AH group continued to lose weight; after the intervention, the lean body mass and relative grip of the AH group were significantly lower than those of the C group (P<0.05). (2) The muscle fiber morphology was damaged in the IH group and the AH group, which was more obvious in the IH group, while the FCSA of TA in each group had no significant difference. (3) The contents of Atrogin-1 and MuRF1 in TA in IH group were significantly higher than those in C group, and the content of MuRF1 in AH group was significantly higher than that in C group (P<0.05). (4) Screening of differential genes found that the differential genes that were up-regulated in AH/C group and down-regulated in IH/C group were slow muscle structure-related genes. GO and KEGG analysis showed that the differential genes in the IH/C group were mainly enriched in the PPAR pathway; the functions of up-regulated differential genes were enriched in the process of antioxidant and glucose and lipid metabolism, and the down-regulated genes were enriched in the transformation between fast and slow muscles and the process of oxidative stress; The functions of up-regulated differential genes in AH/C group were mainly enriched in oxidative stress, inflammatory response and the transition between fast and slow muscle, while the down-regulated genes were enriched in smad protein signal transduction and ubiquitin protein ligase binding.

　　Conclusion Chronic intermittent hypoxia and acute hypoxia affect the differential expression of tibialis anterior muscle in rats, respectively, which are enriched in affecting the level of glucose and lipid metabolism and promoting oxidative stress and inflammatory response, indicating that different hypoxia patterns can affect skeletal muscle through different transcriptional pathways. metabolism.