Role of MVBs and IL-1β in the vascular calcification of type 2 diabetic rats

Abstract

Objective To study the role of matrix vesicles bodies (MVBs) and interleukin-1β (IL-1β) in the vascular calcification of type 2 diabetic rats. Methods In vivo and in vitro vascular calcification models were developed by streptozotocin (STZ) plus vitamin D3 in rats with high-fat diet and β-glycerophosphate and high-glucose medium in vascular smooth muscle cells (VSMCs), respectively. Calcium deposition was detected by PET/CT, Von Kossa staining or alizarin red S staining. The expression of runt-related transcription factor 2 (RUNX 2), annexin-Ⅵ and IL-1β were detected by immunofluorescence staining, real-time quantitative PCR or Western blot. Results The aortic artery of calcified rats and the in vitro VSMCs both showed obvious calcium deposits. Compared to the control group, the expressions of bone morphogenetic protein-2 (BMP-2) and RUNX 2 significantly increased in the calcification group (P＜0.01, P＜0.05). At the same time, the expression of annexin-Ⅵ and IL-1β was also significantly up-regulated (P＜0.01, P＜0.05) and there was a co-localization between them. Rapamycin reduced expression of RUNX-2, annexin-Ⅵ and IL-1β in the calcification group (P＜0.01). After the treatment of chloroquine, the expression of RUNX 2 weas slightly up-regulated and annexin-Ⅵ was high-expressed(P＜0.01). Conclusions Autophagy reduces the release of MVBs and the expression of inflammatory factor IL-1β and so thereby reduces aortic calcification in type 2 diabetic rats.

Keywords

• type 2 diabetes mellitus|vascular calcification|matrix vesicles bodies|interleukin-1β