Anti-inflammatory property of hydrogen-rich Gynostemma pentaphyllum Makino distillate.

Hydrogen-rich Gynostemma pentaphyllum Makino distillate (HRGD) is produced by distilling G. pentaphyllum Makino, with the addition of hydrogen gas. This study sought to explore the pharmacological and biological impacts of HRGD on the generation of pro-inflammatory cytokines and mediators in macrophages. The cells were treated with various concentrations of HRGD (2, 4 and 8 μg/mL) in the absence or presence of lipopolysaccharide (LPS) (1 μg/mL) for 24 h. The results indicated that HRGD is an effective inhibitor of LPS-induced nitric oxide (NO·) production in RAW 264.7 cells: The NO· concentration was reduced dramatically after treatment with 8 μg/m98L HRGD (11.8 μM) compared to the LPS-induced group (28.4 μM). These inhibitory effects of HRGD included a dose-dependent decrease in the expression of cyclooxygenase-2 (COX-2) and prostaglandin E2 (PGE2) proteins. To evaluate the inhibitory effects of HRGD on other cytokines, we also measured cytokines tumor necrosis factor-α (TNF-α) level in the cell supernatants of LPS-stimulated RAW 264.7 macrophages by enzyme-linked immunosorbent assay. In this assay, HRGD significantly decreased the expression of TNF-α in a dose-dependent manner (p < 0.05). The study also performed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on macrophages. HRGD did not display any cytotoxicity in this assay. The findings demonstrated that HRGD could modulate macrophage-mediated inflammatory functions such as the overproduction of cytokines, NO· and PGE2 without any cytotoxic. [ABSTRACT FROM AUTHOR]