Autophagic cell death on reductive cardiac development in STZ‐induced diabetic rats

Abstract

Diabetes is a major predictor of heart failure. However, little is known regarding mechanisms how it causes heart to pathological remodeling and even cardiac dysfunction. Here, we tested the role of autophagy in diabetic cardiac dysfunction. Here, we hypothesized that diabetes induces cardiac autophagy. When H9c2 cells were exposed to low‐glucose and/or glucose‐free media, we observed augmented LC3 expression, which serves as a marker protein for autophagosomes. To confirm whether it does reflection of in vitro evidence compared to in vivo diabetic animal model, diabetic mellitus was induced using by streptozotocin (60mg/kg, IP) at 4‐wks‐age in rats. Body weight and blood glucose level were measured throughout this experiment. The left ventricle (LV) including the interventricular septum was isolated and weighed for body weight and tibial bone length. Diabetic rats have shown the reduction of size of LV rather than hypertrophy according to growth retardation and higher level of LC3 protein expression, suggesting activated autophagic cell death. Taken together, these findings implicate that progression of pathological remodeling of heart development is associated with autophagy. Thereby we suggest further studies regarding effect of diabetic cardiac autophagy on heart dysfunction including heart failure. [Supported by KRF–2006–E00344).