Expression of small heat shock protein family and autophagy related proteins in the hippocampus of db/db mice with spontaneous type 2 diabetes

Abstract

Objective To study the changes of small heat shock proteins (sHSPs) and autophagy-related proteins in hippocampus of spontaneous type 2 diabetic db/db mice. Methods The db/m mice were used as control group, while diabetic db/db mice were used as model group, 10 mice in each group. The body weight, fasting blood glucose (FBG), the expression of small and medium heat shock protein family and autophagy-related genes in hippocampus were detected by real-time PCR, and the expression of HSPB8, BAG3, LC3 and P62 was detected by Western blot. Results 1) The body weight and fasting blood sugar of db/db mice were significantly higher than those of db/m mice(P＜0.01). 2)Small heat shock protein family B [small] member 1-10 (HSPB1-10) gene was expressed in the hippocampus of mice. The expression of HSPB1, HSPB3, HSPB5, HSPB6 and HSPB8 in db/db group was significantly lower than that in db/m group(P＜0.05); the expression of HSPB2, HSPB9 and HSPB10 in db/db group was higher than that in db/m group(P＜0.05); the expression of LC3 in db/db mice was higher than that in db/m group(P＜0.01), whereas the expression of P62 was lower than that of db/m(P＜0.01). 3)The expression of HSPB8, BAG3 and LC3-Ⅱ increased in db/db group(P＜0.01), but the expression of P62 decreased(P＜0.05). Conclusions All sHSPs are expressed in the hippocampus of mice, but the expression profile is different. The expression of HSPB8 protein is increased and autophagy is activated in the hippocampus of 8-week-old diabetic mice.

Keywords

• diabetes mellitus|small heat shock protein|autophagy|db/db mice