Berberine protects vascular endothelial cells in hypertensive rats.

OBJECTIVE This study is to investigate the effect and mechanism of berberine on vascular endothelial cell injury. METHODS The isolated aortic endothelial cells were divided into negative control group, spontaneous hypertension group, and berberine group (1.25, 2.5, and 5 μmol/L berberine). CCK-8 assay was performed to detect cell proliferation. Annexin V-FITC flow cytometry and Hochest33342/PI staining were used to measure cell apoptosis. Expression of TLR4, Myd88, and NF-κB was detected with Western blotting analysis. Level of IL-6 and TNF-α was measured with ELISA. RESULTS Compared with spontaneous hypertension group, cell proliferation in berberine group was significantly improved (P < 0.05). Flow cytometry showed that cell apoptosis was reduced in berberine group in a dose-dependent manner and there was statistically significant difference between spontaneous hypertension group and berberine group (P < 0.05). This result was further confirmed by Hochest33342/PI staining. Expression levels of TLR4, Myd88 and NF-κB were increased in spontaneous hypertension group. However, their expression levels were significantly reduced in berberine group than those in spontaneous hypertension group (P < 0.05). Similarly, levels of IL-6 and TNF-α were increased in spontaneous hypertension group and decreased in berberine group. And, the difference was significant (P < 0.05). Importantly, there were significant differences between negative control group and spontaneous hypertension group in cell proliferation, apoptosis, and expression of TLR4, Myd88, NF-κB, IL-6 and TNF-α. CONCLUSION Berberine plays a protective role in vascular endothelial cell injury through inhibiting apoptosis and expression of TLR4, Myd88, NF-κB, IL-6 and TNF-α.