Anti-Photoaging and Anti-Inflammatory Effects of Ginsenoside Rk3 During Exposure to UV Irradiation.

Ginseng is a widely cultivated perennial plant in China and Korea. Ginsenoside Rk3 is one of the major active components of ginseng and is a promising candidate to regulate skin pigments and exert anti-photoaging effects on skin physiology. Ginsenoside Rk3 was mixed with a cream (G-Rk3 cream) and smeared on the skin of mice. Then, the mice were exposed to ultraviolet (UV) A (340 nm and 40 W) and UVB (313 nm and 40 W) radiation. Special attention was given to the anti-photoaging and anti-inflammatory effects of ginsenoside Rk3 on the mouse skin. Macroscopic evaluation indicated that the mouse dorsal skin looked smooth and plump even under UV irradiation for 12 weeks. Pathological analysis indicated that there was no obvious photoaging or inflammation in the mouse skin that was treated with the G-Rk3 cream. More healthy, intact, and neat collagen fibers were observed in mice treated with the G-Rk3 cream than in untreated mice. Further analysis proved that ginsenoside Rk3 could inhibit the decrease in water and hydroxyproline levels in skin tissues and the loss of superoxide dismutase and glutathione peroxidase activities in the blood. Moreover, ginsenoside Rk3 slowed or halted increases in malondialdehyde, matrix metalloproteinase (MMP)-1, and MMP-3 levels in the blood and levels of interleukin 1, interleukin 6, and tumor necrosis factor α in skin tissues. In conclusion, ginsenoside Rk3 plays a significant role in inhibiting photoaging and inflammation to protect skin health.