BACKGOUND: Inflammation is one of the key mechanisms in the development and progression of atherosclerosis. Accumulating evidence suggests that peroxisome proliferators- activated receptorgamma(PPARgamma) plays an important role in the prevention of arterial inflammation and the formation of atherogenesis. This study was designed to evaluate whether the new synthetic PPARgamma, ascochlorin-6(AS-6) has anti-inflammatory and anti-atherogenic effects in primary cultured rat vascular smooth muscle cells(VSMCs). METHODS: Rat VSMCs were isolated and cultured. Northern and Western blot analyses were performed to evaluate the effects of AS-6 on the expressions of tumor necrosis factor (TNF)-alpha-stimulated fractalkine, monocyte chemoattractant protein(MCP)-1 and vascular cell adhesion molecule (VCAM)-1 in VSMCs. A gel shift assay was performed to examine the mechanism by which AS-6 inhibits the expressions of fractalkine, MCP-1 and VCAM-1. RESULTS: TNF-alpha markedly induced the expressions of fractalkine, MCP-1 and VCAM-1 in primary cultured VSMCs. AS-6 inhibited the expressions of TNF-alpha-stimulated fractalkine, MCP-1 and VCAM-1 in primary cultured VSMCs. The result of the gel shift assay suggested the inhibitory effects of AS-6 on the expressions of TNF-alpha-stimulated fractalkine, MCP-1 and VCAM-1 were mediated through a nuclear factor kappaB associated pathway. CONCLUSION: The present study shows that AS-6 has anti-inflammatory effects on VSMCs, suggesting the possibility for the use of AS-6 for prevention of the development and progression of atherosclerosis.