RESUMO
Objective Vascular smooth muscle cells are the main cells in atherosclerosis. Reports are rarely seen on influenza virus infection on human aortic smooth muscle cells (HASMC) and its influence on the expressions of the related cytokines. This study was to investigate the impact of influenza A virus (IAV) and influenza B virus (IBV) infection on HASMCs and the expressions of cytokines. Methods HASMCs were stimulated with IAV or IBV or not stimulated with virus (the control). The nucleoprotein of the influenza virus in the cells was detected by immunofluorescence assay, the proliferation of the cells determined with CCK8, and the level of influenza virus RNA in the supernatant measured by qPCR. The collected supernatant was used to infect Madin-Darby canine kidney (MDCK) cells and detect the influenza virus nucleoprotein. The expressions of the cytokines of the influenza virus after 24 hours of infection were determined by qPCR. Results At 3 and 4 days after infected with influenza virus, the proliferation of the HASMCs was significantly inhibited in the IAV and IBV groups as compared with the control (P<0.05). The expression of virus RNA in the supernatant of the IBV group at 3 days was 5.75 times as high as that at 2 days (P<0.05), dropped at 4 days but still higher than that at 2 days (P<0.01). Compared with the normal culture medium, the medium with virus growth fluid significantly elevated the RNA level of IAV (0.842±0.148 vs 15.182±1.932, P< 0.01) and IBV (0.962±0.033 vs 4.029±0.681, P<0.01). After infection, the expression of MCP-1 was remarkably up-regulated in the IAV and IBV groups (4.364±0.193 and 3.348±0.507) in comparison with that in the control group (1.001±0.001) (P<0.05), and so were the expressions of IL-6 and TNF-α (P<0.05). Conclusion Both IAV and IBV can infect HASMCs and increase the expressions of the cytokines MCP-1, IL-6 , and TNF-α.