Abstract
OBJECTIVE To study the anti-fatigue effects of differently-cultivated Astragalus extract in a hypoxic environment of the plateau and explore the related mechanisms.METHODS Fifty-six male KM mice were randomly divided into the hypoxic swimming control(HSC)group,imitation wild Astragalus extract(IWA)430,860 and 1 720 mg·kg-1 groups,and cultivated Astragalus extract(CA)463,925 and 1 850 mg·kg-1 groups.The drug was administered by gavage once daily for 15 days,while body mass was monitored every three days.After 15 days of gavage,the mice were subjected to load swimming(5%body weight)in a hypobaric chamber(simulating a 4 000 m altitude),with exhaus-tive swimming time measured to identify the optimal dosage.Following randomization,fifty male KM mice were assigned to five groups:normoxic control(NC),hypoxic control(HC),HSC,IWA 860 and CA 925 mg·kg-1.All groups underwent daily gavage for 15 d before 90 min non-weight-bearing swimming was conducted in the HSC,IWA 860 and CA 925 mg·kg-1 groups within a hypobaric chamber,followed by immediate measurement of muscle strength.Hematoxylin-eosin(HE)staining was used to observe the histopathological changes in liver and gastrocnemius muscle tissues.Blood urea nitrogen(BUN),blood glucose(BG)and serum lactic acid(LA),glutathione(GSH),glutathione peroxidase(GSH-Px),malondialdehyde(MDA),superoxide dismutase(SOD),liver glycogen(LG)and muscle glycogen(MG)in livers and muscles,and total antioxidant capacity(T-AOC)and reactive oxygen species(ROS)in muscles were measured by commercial kits.Taurine and hypotaurine were measured by HPLC.Enzyme-linked immunosorbent assay(ELISA)was used for cysteine sulfenic acid decarboxylase(CSAD)measure-ment.Western blotting was used to detect protein expressions of phosphatidylinositol 3-kinase(PI3K),protein kinase B(Akt),nuclear factor E2-related factor 2(Nrf2),and heme oxygenase-1(HO-1)in skeletal muscles.RESULTS Compared with the HSC group,the swimming time was prolonged in IWA 463,IWA 860,CA 925 and CA 1 850 mg·kg-1 groups.Compared with the HSC group,the muscle strength of mice in the IWA 860 mg·kg-1 group and the CA 925 mg·kg-1 group was significantly increased,histo-pathological damage in the liver and gastrocnemius muscle was reduced,serum levels of LA and BUN were significantly decreased,levels of BG,LG and MG were significantly increased,levels of GSH,GSH-Px and SOD were significantly increased,contents of MDA were significantly decreased,expressions of CSAD were significantly increased in liver tissue,contents of GSH,T-AOC,taurine and hypotaurine were significantly increased,levels of ROS were significantly decreased,and protein expressions of PI3K,Akt,Nrf2,HO-1 were significantly upregulated in muscle tissues.CONCLUSION Under simulated high-altitude hypoxic conditions,extracts of Astragalus membranaceus cultivated by two methods consis-tently exhibit anti-fatigue effects.Its mechanisms may be mitigating oxidative stress,augmenting taurine and hypotaurine metabolic regulation,and activating PI3K/Akt and Nrf2/HO-1 signaling pathways.IWA has a better anti-fatigue effect than CA.关键词
黄芪水提物/低压低氧/氧化应激/抗疲劳Key words
Astragalus extract/hypobaric hypoxia/oxidative stress/anti-fatigue分类
医药卫生
