Molecular and Biochemical Studies on Mitocondrial DNA in Diabetic Rats

Summary:-The present study was performed to study the effect of both type one and two diabetes on some the mitochondrial genes expression (NAD-H dehydrogenase subunit one and cytochromoxidase subunit 3) and subsequent effect of diabetes on antioxidants (Sstudy was carried out on fourty fife male rats weighting 200 gm which divided into three groups in each on fifteen rats :1-First group :- Rats were kept as control .2-Seconed group(type one diabetic rats):- In this group fifteen rats were fed on chow diet and were diabetic by using streptozotocin as a single intra peritoneal injection dose of 65 mg/kg body weight and maintained for 1 week.3-Thired group(type two diabetic rats):-In this group rats were fed on high-sucrose and high-fat chow. After six-week feeding,injected IP with freshly prepared STZ at a single dosage of 30 mg/kg body weight .Blood glucose level were determined using one touch apparatus to indicate diabetes and then control and diabetic rats were scarified and the following sample were collected :1- whole blood during scarification : for serum separation to determine serum glucose.2- Tissue sample : take liver and muscle samples immediately for molecular analysis in liquid nitrogen container also take skeletal muscle , liver and kidney samples for biochemical studies in deep freezer at -20 °c.For biochemical measurement of antioxidants we make tissue homogenate from liver , muscle , and kidney (1gm tissue in 9 ml saline then make homogenization in homogenizer). The result of the study can be summarized as follows:- On comparing between the groups the gene expression of ND1 and COX3 are increases in liver and muscle of type one diabetic rats in comparing with control group.- On comparing between the groups the gene expression of ND1 and COX3 are increases in liver and muscle of type two diabetic rats in comparing with control group .- On comparing between the groups the gene expression of ND1 and COX3 are increases in liver and muscle of type one diabetic rats more than in type two diabetic rats .- Concerning to the results the blood glucose of type one diabetic rats is higher than type two diabetic rats .- Concerning to the results the SOD and catalase is significantly decreased in liver , muscle and kidney of type one diabetic rats in comparison to control group .- Concerning to the results the SOD and catalase is significantly decreased in liver , muscle and kidney of type two diabetic rats in comparison to control group .- Concerning to the results the SOD and Catalase is decreased in liver , muscle and kidney of type one diabetic rats in comparison to type two diabetic rats .- There is positive correlation between SOD and Catalase in liver , kidney and muscle in both type one and type two diabetes .It could be concluded that :1- There is increase in ND1 and Cox3 gene expression in liver and muscle of both type one and two diabetes .2- There is Decrease in the activity of SOD and Catalase of both type one and two diabetes .3- As the blood glucose increase in diabetic state lead to further increase in ND1 and Cox3 gene expression in liver and muscle and subsequent decrease in antioxidant ( SOD and Catalase ) .- from our work we can recommended that:from the result we found that by increase the blood glucose level in diabetic state lead to further increase in mitochondrial gene expression and further decrease in antioxidants so diabetic patient should be controlled ( by insulin or hypoglycemic drugs