ABSTRACT
Objective To research the relationship between miR-21 and radiation sensitivity of cervical cancer HeLa cells,and to elucidate the possible action mechanism of miR-21 in apoptosis and autophagy of cells.Methods The HeLa cells were divided into mock groups (transfected with miR-21 NC,mimics,inhibitor NC or inhibitor)and 4 Gy irradiation groups (transfected with miR-2 1 NC, mimics,inhibitor NC or inhibitor with irradiation). The miR-2 1 expression was detected by real-time PCR;colony-forming assay was used to detect the changes of radiation sensitivity;the apoptosis and autophagy were analyzed by FACS assay;the target gene of miR-2 1 was predicted by bioinformatics methods;Dual-luciferase Reporter Assay was used to demonstrate the binding of miR-2 1 and targets;the expression of beclin1 protein was measured by Western blotting method. Results After 4 Gy radiation,compared with mock group,the expression of miR-21 was increased remarkably (P0.05).Compared with miR-21 NC+4 Gy group,the apoptotic rate of HeLa cells in miR-21 mimics+4 Gy group was increased (P<0.05).After transfection with miR-21 inhibitor,compared with miR-21 inhibitor NC group,the apoptotic rate of HeLa cells in duced by radiation was decreased (P<0.05 ). Compared with miR-21 NC group, the autophagy rate was increased after transfection with miR-21 mimics (P<0.05).After transfection with miR-21 mimics and radiation, the expression level of beclin1 protein was increased (P<0.05 ) compared with miR-21 NC+4 Gy group. Conclusion Beclin1 is the target gene of miR-21 in HeLa cells. Overexpression of miR-21 can increase the radiation-induced apoptosis and autophagy,but has on influence in radiation sensitivity of HeLa cells.
ABSTRACT
Objective To explore the effects of 75 mGy irradiation on the apoptosis of spermatogenic cells and antioxidant capacity of serum and testis and hormone levels in male rats with diabetes mellitus(DM).Methods Rats were injected intraperitoneally with streptozotocin(STZ)to develop diabetes.The diabetic rats were irradiated with 75 mGy X-rays every other day for 4 weeks.Their survival rate and body weight were recorded 12 weeks after development of diabetes.The apeptosis percentage of germ cells was measured with flow cytometry and TUNEL method.The changes of anti-oxidation and gonadal hormone levels in serum and testis were measured with kits.Results After the rats suffered from diabetes for 12 weeks,the survival rate in DM group was 25%(6/24),100% in normal control group(16116).The survival rate in 75 mGy + DM group(9/16,56.25%)was obviously higher than that in the DM group(X2= 4.00,P < 0.05).Meanwhile,the percentage of apaptotic spermatogenic cells in the diabetic rats was significantly larger than those in the normal control and irradiation groups(F = 5.496,P < 0.05).MDA and NO levels in serum and testis of diabetic rats were higher in varying degrees than that in the normal control,while the serum and testis MDA content in the 75 mGy + DM group were lower than those in the DM group especially in the testis(F = 10.644,P < 0.01).75 mGy X-ray irradiation decreased NO content in the diabetic rats serum significantly(F = 14.379,P < 0.05)and increased NOS activity and TS,FSH level(F = 9.676,43.194 and 5.282,respectively,P < 0.05 and P < 0.01).Conclusions LDR could decrease the MDA level and NO content,and increase the antioxidant enzyme activity and TS and FSH levels in testis and serum of diabetic rats.