Expression Of Bnip-3, Bcl-2, Caspase-3 And HIF-1 In Experimental Diabetic Cardiomyopathy

Diabetes is one of the three most main diseases. It becomes to be the research point because of its increasing incidence date these years. Diabetic cardiomyopathy is the complicating disease that independent of macroangiopathy. In the pathogenic research of diabetic cardiomyopathy, the researcher identified the existence of cardiac myocyte apoptosis in diabetic cardiomyopathy. Apoptosis is different from cell death, which is active and programmed cell death. Its generation and development is under the control of gene expression. The new research on this transfer the focus on the specific enzymolysis process of the key proteins. The functions of caspase-3, Bcl-2 and Bnip-3 are more elucidated in tumor. The significance of their expression in diabetic cardiomyopathy is still unknown.This study established the rat diabetic cardiomyopathy model induced by STZ. We detected the blood glucose level by glucose hydrocarbonylation procedure, cholesterol by enzymatic method, triglyceride level, high density lipoprotein and low density lipoprotein level, insulin level by radio-immunity. We also detected the expression of troponin-I by immunifaction and the expression of Bnip-3, Bcl-2,caspase-3 and HIF-1 in cardiac myocyte.The results were as follows. The blood glucose level of the experimental group was 25.08±7.14mmol/l which was significant higher than 7.27±1.10lmmol/l of the control group. (P<0.001). The insulin level of the experimental group was 7.80±2.33mmol/l which was significant lower than 16.58±5.48mmol/l of the control group. (P<0.001) The troponin-I of the experimental group was 0.078±0.068 which was significant higher than 0.008±0.007 of the control group。(p<0.05).The cholesterol level of the experimental group was 2.64±0.53mmol/l which was significant higher than 0.80±0.17mmol/l of the control group。(p<0.0001).The triglyceride level of the experimental group was 2.79±0.67mmol/l which was significant higher than 1.56±0.19mmol/l of the control group。(p<0.001).The LDL level of the experimental group was 1.74±0.497mmol/l which was significant higher than 0.86±0.09mmol/l of the control group。(p<0.001).The HDL level of the experimental group was 0.88±0.10mmol/l which was significant lower than 1.33±0.230mmol/l of the control group。(p<0.001)。All of this results were significant. The immunohistochemistry analysis showed that Bnip positive expression was located in the cytoplasm and nucleolus. Its positive expression ratio was 60.61±14.92(%)in the experimental group which was significant higher than36.06±5.43(%)in the control group.(P<0.001). The positive expression of Bcl-2 was located in the cell membrane and/or cytoplasm. Its positive expression ratio was 22.34±12.70(%)in the experimental group which was significant lower than74.03±10.45(%)in the control group.(P<0.001).The positive expression of caspase-3 was located in the cytoplasm and nucleolus. Its positive expression ratio was 92.42±7.51(%)in the experimental group which was significant higher than 9.94±21.22(%)in the control group.( P<0.0001). The positive expression of HIF-1 was located in the cytoplasm and nucleolus. Its positive expression ratio was 47.39±8.63(%)in the experimental group which was significant higher than 28.99±10.37(%)in the control group.( p<0.05). All the results were significant.In summary, the blood glucose level, blood fat increased significantly in the diabetic cardiomyopathy. The increased troponin-1 demonstrated the injury of the cardiac myocyte. The significantly increased expression of Bnip-3, caspase-3 ,HIF-1 and the decreased expression of Bcl-2 showed that Bnip-3 may be associated with cell apoptosis. Its increased expression promoted the cell apoptosis. This could be one of the causes that induced the early pathological changes of the diabetic cardiomyopathy. Its expression may be induced HIF-1 and inhibited by the expression of Bcl-2. It may induce cell apoptosis though caspase pathway. The regulatory mechanism of Bnip-3 ,caspase-3, Bcl-2 and HIF-1 need further research to identify.