Effects of vibration on expressions of vascular endothelial inflammatory factors and IncRNA MEG3 in vitro

Background Prolonged exposure to vibration can cause vascular endothelial injury, and inflammatory response plays an important role in vascular endothelial injury. Studies have shown that long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3) is involved in regulating the expression of inflammatory injury of endothelial cells.

Objective To investigate the effects of vibration on the secretion of inflammatory factors and the expression of IncRNA MEG3 by vascular endothelial cells in vitro.

Methods Human umbilical vein endothelial cells (HUVEC) were divided into two categories: vibration and control. The vibration exposure included 63 Hz (6.76 m·s⁻²), 200 Hz (5.08 m·s⁻²), and 250 Hz (4.56 m·s⁻²) frequency bands, and 1 and 2 d exposure time with 1 to 4 h of daily vibration. The control treatment was the same as the vibration category except that they were not exposed to vibration. CCK-8 was used to detect the effects of different vibration frequencies and time on the viability of HUVEC. The expression levels of tumor necrosis factor-α (TNF-α), interleukin-8 (IL-8), interleukin-4 (IL-4), and interleukin-10 (IL-10) in the cells and supernatants were detected by enzyme-linked immunosorbent assay. The expression levels of IncRNA MEG3 were detected by real-time fluorescence quantitative PCR.

Results Compared with the cells with the control treatment, the cell viability of the 1-day exposure group increased after 1.5 h and 3 h of vibration at 63 Hz, while decreased after 2 h and 2.5 h; the cell viability of the 2-day exposure group increased at the frequency of 63 Hz for 1.5 h, but decreased at 2 h and 2.5 h. At the frequency of 200 Hz, the cell viability of the 1-day exposure group increased at 2 h and 4 h, but decreased at 2.5 h and 3 h; the cell viability of the 2-day exposure group increased at 1.5 h and decreased at 2.5 h. For the vibration exposure at frequency of 250 Hz, the cell viability of the 1-day exposure group increased at 1.5 h and 2.5 h, but decreased at 3 h; of the 2-day exposure group, the cell viability increased at 1.5 h and decreased at 3 h. For the exposure settings of 63 and 200 Hz vibration for 2.5 h and 250 Hz vibration for 3 h, and with the control treatment as reference, the expression levels of TNF-α, IL-8, IL-4, and IL-10 in cells and supernatants were increased in the 1 d and 2 d exposures; the expression level of lncRNA MEG3 decreased in the 1 d exposure group; however, for the 2 d exposure, the expression level of lncRNA MEG3 decreased only in the 63 Hz vibration exposure. All of these results were statistically significant (P<0.05).

Conclusion Vibration could induce an increase in the levels of inflammatory factors TNF-α, IL-8, IL-4, and IL-10 and a decrease in the expression level of lncRNA MEG3 in vascular endothelial cells in vitro.