Conclusions
20(R)-Rh2, a minor stereoisomer of ginsenoside Rh2, possesses matrix metalloproteinase inhibitory, anti-inflammatory and antioxidative activity.
Methods
In-vitro anti-inflammatory activity of 20(R)-Rh2 was evaluated by analysing nitric oxide (NO) and prostaglandin E2 (PGE2) contents in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. Its antioxidant activity was determined by measuring the level of reactive oxygen species (ROS) in the macrophage and keratinocyte cells. Matrix metalloproteinase-9 (MMP-9) and -2 (MMP-2) activity in the culture medium was detected using zymography. Key findings: 20(R)-Rh2 was able to suppress NO, PGE2, ROS and pro-matrix metalloproteinase-9 (pro-MMP-9) levels that were enhanced in the LPS-stimulated murine RAW264.7 macrophage cells. 20(R)-Rh2 also exhibited inhibitory effects on the level of ROS and the activity of MMP-9 and -2 in human HaCat keratinocyte cells without stimulant exposure. 20(R)-Rh2 could suppress the gelatinolytic activity of MMP-9 enhanced by tumour necrosis factor-α in the keratinocytes. Conclusions: 20(R)-Rh2, a minor stereoisomer of ginsenoside Rh2, possesses matrix metalloproteinase inhibitory, anti-inflammatory and antioxidative activity.