The Chinese medicinal formula
Guanxin Shutong capsule (GXSTC) has been used for almost 10 years as a clinical treatment for
chest pain, depression, palpitation and
cardiovascular diseases. The aim of this study was to investigate the effects of GXSTC
drug-containing serum on
tumor necrosis factor-α (TNF-α)-stimulated endothelial cells. Cell viability was measured by MTT assay, and
nitric oxide (NO) levels and
NO synthase (NOS) activity were measured as standards of endothelial dysfunction.
Malondialdehyde (MDA) levels and
superoxide dismutase (SOD) activity were evaluated using commercial kits. In addition, the
protein expression of endothelial NOS (eNOS), AKT and
nicotinamide adenine dinucleotide phosphate (
NADPH) oxidase subunits was examined to evaluate the effect of GXSTC
drug-containing serum on ECV304 cells. GXSTC significantly reversed the decrease in NO production induced by TNF-α (5 ng/ml) in ECV304 cells. The expression of
NADPH oxidase subunits was increased by TNF-α treatment, but markedly inhibited by treatment with GXSTC in TNF-α-stimulated cells. In summary, GXSTC increased the production of NO in ECV304 cells and exerted a protective effect on ECV304 cells stimulated with TNF-α by upregulating the
mRNA and
protein expression of eNOS. This was accompanied by increased SOD activity and reduced MDA levels. These results suggested that GXSTC protects the endothelium via the NO pathway and exhibits
antioxidant effects.