Atherosclerosis is a chronic inflammatory disease in the vessel, and inflammatory
cytokines play an important role in the inflammatory process of
atherosclerosis. A high level of
free fatty acids (FFAs) produced in
lipid metabolism disorders are known to participate in the formation of
atherosclerosis through multiple bioactivities. As the main
saturated fatty acid in FFAs,
palmitic acid stimulates the expression of inflammatory
cytokines in macrophages. However, it is unclear whether
palmitic acid exerts a pro-inflammatory effect on vascular smooth muscle cells (VSMCs). The purpose of the present study was to observe the effect of
palmitic acid on the expression of
C-reactive protein (CRP),
tumor necrosis factor α (TNF-α) and
inducible nitric oxide synthase (iNOS) in VSMCs. Rat VSMCs were cultured, and
palmitic acid was used as a stimulant for CRP, TNF-α and iNOS expression.
mRNA expression was assayed with reverse transcription-polymerase chain reaction, and
protein expression was detected with western blot analysis and immunocytochemistry. The results showed that
palmitic acid significantly stimulated
mRNA and
protein expression of CRP, TNF-α and iNOS in VSMCs in time- and concentration-dependent manners, and therefore,
palmitic acid is able to exert a pro-inflammatory effect on VSMCs via stimulating CRP, TNF-α and iNOS expression. The findings provide a novel explanation for the direct pro-inflammatory and atherogenic effects of
palmitic acid, and for the association with
metabolic syndrome, such as
type 2 diabetes mellitus,
obesity and
atherosclerosis. Therefore, the intervention with
anti-inflammatory agents may effectively delay the formation and progression of
atherosclerosis in patients with
metabolic syndrome.