Anti-Atherosclerotic Effect of Afrocyclamin A against Vascular Smooth Muscle Cells Is Mediated via p38 MAPK Signaling Pathway

Document Type : Original Article

Authors

1 Department of Vascular Surgery, Tianjin First Center Hospital, Tianjin, China

2 Department of Emergency Services, The Fourth People’s Hospital of Jinan City, Jinan, Shandong Province, China

3 Department of Vascular Surgery, The Affiliated Hospital of Qingdao University, Qingdao City, China

4 4Department of Hematology, The Fourth People’s Hospital of Jinan City, Jinan, Shandong Province, China

Abstract

Objective
Research suggests that fine particulate matter (PM2.5) contributes to the expansion and development of atherosclerosis. Infiltration and proliferation of vascular smooth muscle cells (VSMCs) from the blood vessel media into the intima, is an important step in the atherosclerosis pathophysiology. Afrocyclamin A, is an oleanane-type triterpene saponin, isolated from Androsace umbellate, which is commonly used in Chinese herbal medicine. In the study, we examined the effect of Afrocyclamin A on PM2.5-induced VSMCs proliferation and scrutinized possible mechanisms of action.
Materials and Methods
In the experimental study, counting Kit-8 (CCK-8) assay was used for estimation of VSMCs viability. BrdU immunofluorescence was used for estimation of VSMCs proliferation. The levels of antioxidant parameters such as malonaldehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH); proinflammatory cytokines such as interleukin-1β (IL-1β), IL-6, tumor necrosis factor-α (TNF-α), nitric oxide (NO), endothelin-1 (ET-1), and vascular cell adhesion molecule-1 (VCAM-1), were estimated. The expression of proliferating cell nuclear antigen (PCNA) and phospho-p38 MAPK (p-p38 MAPK) was assessed.
Results
Compared to PM2.5-treated cells, in addition to reducing PM2.5-induced VSMCs proliferation, Afrocyclamin A reduced the expression of PCNA and p-p38 MAPK, down-regulated the level of TNF-α, IL-1β, IL-6, VCAM-1, MDA and ET-1, and up-regulated SOD, GSH and NO level. Furthermore, the anti-proliferative effect of Afrocyclamin A was considerably increased following co-incubation of Afrocyclamin A with SB203580 (p38 MAPK inhibitor) in comparison with Afrocyclamin A-treated cells.
Conclusion
Based on the results, we can conclude that Afrocyclamin A might reduce PM2.5-induced VSMCs proliferation via reduction of p38 MAPK signaling pathway.