The Effect of High Glucose on the Proliferation and Migration of Vascular Smooth Muscle Cells

Kim, Mi Kyoung; Kang, Yang Ho; Son, Seok Man; Kim, In Ju; Kim, Yong Ki

Abstract

BACKGROUND: Oxidative stress contributes to vascular diseases for patients with diabetes by promoting vascular smooth muscle cell (VSMC) proliferation, monocyte/macrophage infiltration, and vascular tone alteration. As the mechanism of development and progression of diabetic vascular complications is poorly understood, this study was aimed to assess the potential role of hyperglycemia-induced oxidative stress and to determine whether thise oxidative stress is a major factor in hyperglycemia-induced migration and proliferation of VSMCs.
METHODS
Rat aortic VSMCs were incubated for 48 hours in either a normal glucose (NG, 5.5 mM) or a high glucose (HG, 30 mM) condition. We then measured the proliferation and migration of VSMCs and the superoxide production.
RESULTS
The migration and proliferation of VSMCs incubated under a HG condition were markedly increased compared to the NG condition. Treatment with diphenyleneiodonium (DPI, 10 M) and superoxide dismutase (SOD, 500 U/mL) significantly suppressed the HG-induced migration and proliferation of VSMCs. Superoxide production was significantly increased in the HG condition, and it was markedly decreased after a treatment with DPI and SOD.
CONCLUSION
These data suggest that HG-induced VSMC migration and proliferation are related to the production of superoxide anion that is derived from NAD(P)H oxidase.