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OBJECTIVE: To analyze the influence of signal transducers and activators of transcription 2(STAT2) on the apoptosis of oxidative stress-induced HEI-OC1 hair cells. METHODS: With random number table method,HEI-OC1 hair cells were divided into interference group and non-interference group. The artificial synthesis design targeted STAT2 small interfering RNA(siRNA) and opti-modified Eagle medium(opti-MEM) were added into the interference group, and only the opti-MEM was added into the non-interfere group. The 0, 20, 40, 60 μmol/L of tertiary butyl peroxide hydrogen(t-BHP) was added into the interference and non-interference group. Western blotting was used to detect the relative expression of STAT2 and cysteine protease(caspase)-3. The apoptotic rate of hair cells was detected by flow cytometry. RESULTS: In the interference group and non-interference group, the apoptotic rate of HEI-OC1 cells and the relative expression level of STAT2, Caspase-3 increased with the dose of t-BHP(P<0.01). The apoptotic rate of HEI-OC1 cells and the relative expression level of Caspase-3 in the interference group with 20, 40, 60 μmol/L of t-BHP were higher than that of the 20, 40 μmol/L group(P<0.01). The apoptotic rate of HEI-OC1 cells in the interference group was higher than those in the non-interference group with the same dose(P<0.01), while the relative expression level of STAT2 was lower than those in the non-interference group with the same dose(P<0.01). CONCLUSION: Inhibiting oxidative stress and STAT2 expression in hair cells can lead to aggravation of apoptosis. STAT2 has anti-apoptotic effect.
RESUMO
Objective To study the biological effects of (Janus Kinase-Signal transducers and activators of transcription,AK-STATs)path-way in hair cell apoptosis by analyzing the expression level of signal transducers and activators of transcription (STATS) of apoptotic HEI-OC1 cells line induced by oxidative stress injury.Methods Using different poisoning concentrations (0,20,40,60μM) of(Tert-Butyl hydroperoxide,T-BHP) built the apoptotic HEI-OC1 cells model while 0 μM was used as the control group.The apoptosis level at different poisoning concentration groups was detected by Annexin V-FITC/PI and the expression level of STATs mRNA by real-time quantitative PCR detecting system.Results The apoptosis rates in different contamination groups(0,20,40,60 μM) were 3.9％,7.4％,32.0％,and 91.2％,respectively.Compared with control group,STAT1 mRNA,STAT3 mRNA,STATS mRNA,and STAT6 mRNA expression levels in different poisoning concentration groups declined significantly (F=5 534.302,P＜0.01;F=146.038,P＜0.01;F=685.929,P＜0.01;F=516.11,P＜ 0.01).No statistically significant differences were found among the poisoning concentration groups (P＞0.05).Compared with the control group,the STAT2 mRNA expression levels changed significantly (F=1 259.148,P＜ 0.01).The STAT2 mRNA expression level in 20 μM contamination group decreased while 40,60 μM contamination group increased significantly (P＜0.01).No expression of STAT4 in HEI-OC1 cell was noted.Conclusion The JAK-STAT2 signal pathway has the biological effects on leading oxidative stress injury apoptosis and JAK-STAT1/STAT3/STAT5/STAT6 has the biological effect of inhibit oxidative stress injury apoptosis.