The aim of this study was to investigate the role of mitofusin-2 (Mfn2) in different stages of diabetes in rats and to analyze the related mechanism(s). A diabetic model in SD rats was induced by a single
intraperitoneal injection of 55 mg/kg streptozoticin (STZ). The hearts were isolated from
diabetes mellitus (DM) rats at the fourth week (DM4W), eighth week (DM8W) and twelfth week (DM12W) and fasting
blood glucose (FBG) levels and the ratio of heart weight to
body weight (HW/BW) were measured.
Malondialdehyde (MDA) content,
superoxide dismutase (SOD) and
caspase 3 activities were measured. The expression of Mfn2 of the left anterior myocardium at the
mRNA level was detected using RT‑PCR. In contrast to the normal group, in the DM4W, DM8W and DM12W groups, there was a significant increase in the FBG levels, but no difference among the DM4W, DM8W and DM12W groups. The HW/BW ratio as well as the MDA content were increased, while SOD activity was reduced. Caspase‑3 activity was increased, while the expression of Mfn-2
mRNA levels was reduced. In addition, with the development of
diabetic cardiomyopathy, the contents of MDA and
caspase 3 were increased, whereas SOD activity and Mfn-2
mRNA levels were further reduced. In conclusion, our results indicated that with the development of diabetes, the expression of cardiac Mfn2 has showed a decrease, which may be associated with the decrease of
antioxidant ability and progression of apoptosis.