Expression Of CLIC4 And Apoptotic Protein In C6 Glioma Cells Injuried By Lipopolysaccharide And H₂O₂

Glioma is the highest morbility tumor in intracalvarium, and it holds 90% in CNS tumor. The invasion and diversion of glioma is the main reason of tumor recurrence, bad prognosis, failure therapy and patient death. Therefore, it is one of the most important study in medical research to explore the valid therapy ways to cure the glioma.There are some disputes about LPS's function in cell damage. Some research supposed LPS could promote many cytokine release, including TNF synthesis and release and contribute to cell damage. mtCLIC/CLIC4 is one of chloride intracellular channel members, and is controlled by TNF-αand p53. The increasing expression of CLIC4 can induce cell apoptosis.Objective: The cell damage model of rat glima was obtained with Hydrogen Peroxide (H2O2). To observe the effect of Lipopolysaccharide (LPS) on malignant glioma C6 cells injuried with observing the expression change of Bcl-2, Bax, Caspase3 and CLIC4.Methods : The LDH release rate was detected by ultraviolet spectrophotometry, the apoptotic rate of C6 cell was determined by TUNEL, Bcl-2, Bax, Caspase-3 mRNA level was detected by RT-PCR and Bcl-2, Bax, Caspase-3, Cyt-C, and CLIC4 protein level was detected by Western Blotting. Results: Compared with the control group, the apoptotic rate and LDH release rate increased in LPS treated group(P﹤0.05), the expression of Caspase-3 increased, but the Bcl-2, Bax, CLIC4 and cytosolic Cyt-C expression did not change. the apoptotic rate and LDH release rate increased in H2O2 treatment group(P﹤0.05), the expression of Bcl-2 decreased, Bax, Caspase-3, CLIC4 protein level increased obviously. When compared with the H2O2 group, the apoptotic rate and LDH release rate increased in the LPS combining with H2O2 treatment group(P﹤0.05), the expression of Bcl-2 decreased, but Bax, Caspase-3, cytosolic Cyt-C increased, and the CLIC4 expression did not change.Conclusion:LPS and H2O2 can induce the apoptosis in C6, respectively. The combination effect is enhanced. It suggested that LPS combining with H2O2 can aggravate the injury of C6 cells through down-regulated Bcl-2, up-regulated Bax and the overactivation of Caspase-3. The mitochondrial chloride intracellular channel CLIC4 is involved in the oxidative injury of C6, but is not involved in C6 injury induced by LPS.