[Protective effect of Astragalus polysaccharide on MRC-5 cells from oxidative damage induced by hydrogen peroxide].
OBJECTIVE
To investigate the effects of Astragalus polysaccharide (APS) on the expressions of apurinic/apyrimidinic endonuclease/redox factor-1 (APE/Ref-1) and thioredoxin (TRX) in MRC-5 human embryo lung fibroblasts induced by hydrogen peroxide (H2O2) and explore the mechanism of APS protecting MRC-5 cells from oxidative damage.


METHODS
The MRC-5 cells were randomly divided into groups: the normal control group, groups induced by H2O2 of different concentrations, groups treated with 200, 400, 800 mg/L APS. The inhibitory rate of cell proliferation in H2O2-induced MRC-5 cells was measured by MTT assay to make sure the successful establishment of oxidative damage model. With the optimal concentration of H2O2 and different concentrations of APS on MRC-5 cells, we determined the optimal concentrate of APS to prevent oxidative damage in MRC-5 cells. The level of 8-hydroxy-2'-deoxyguanosine (8-OHdG) was detected by immunofluorescence staining. The apoptotic cells were identified by flow cytometry (FCM). The mRNA and protein levels of APE/Ref-1 and TRX were respectively detected by reverse transcription PCR and Western blotting.


RESULTS
H2O2 induced oxidative damage in MRC-5 cells in a concentration-dependent manner. We chose the oxidative damage model induced by 800 μmol/L H2O2 for 24 hours to further study the protective mechanism of APS. Compared with H2O2 control groups, 200 mg/L APS significantly increased the protein level of APE/Ref-1 and TRX, decreased the content of 8-OHdG and the apoptosis of MRC-5 cells, and improved dramatically the cell viability.


CONCLUSIONS
H2O2 can induce oxidative damage in MRC-5 cells. APS can promote APE/Ref-1 and TRX expressions in the damaged MRC-5 cells to relieve the oxidative damage and inhibit cell apoptosis.
School of Basic Medicine, Jiamusi University, Jiamusi 154007, China.
Juexiao
J
Chen
School of Basic Medicine, Jiamusi University, Jiamusi 154007, China.
Guifen
G
Wang
School of Life Science, Jiamusi University, Jiamusi 154007, China.
Li
L
Li
School of Basic Medicine, Jiamusi University, Jiamusi 154007, China.
Pengxia
P
Zhang
D000080242:8-Hydroxy-2'-Deoxyguanosine; D017209:Apoptosis / Q000187:drug effects; D027883:Astragalus Plant / Q000737:chemistry*; D015153:Blotting, Western; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase / Q000235:genetics / Q000378:metabolism; D003849:Deoxyguanosine / Q000031:analogs & derivatives / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005434:Flow Cytometry; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008168:Lung / Q000166:cytology / Q000196:embryology; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects; D011134:Polysaccharides / Q000494:pharmacology*; D020011:Protective Agents / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013879:Thioredoxins / Q000235:genetics / Q000378:metabolism
D016877:Oxidants; D011134:Polysaccharides; D020011:Protective Agents; D013879:Thioredoxins; D000080242:8-Hydroxy-2'-Deoxyguanosine; D006861:Hydrogen Peroxide; C085108:APEX1 protein, human; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D003849:Deoxyguanosine