Inhibitory mechanism of Korean Red Ginseng on GM-CSF expression in UVB-irradiated keratinocytes

Abstract

BackgroundUV-irradiated keratinocytes secrete various proinflammatory cytokines. UV-induced skin damage is mediated by growth factors and proinflammatory cytokines such as granulocyte macrophage colony stimulating factor (GM-CSF). In a previous study, we found that the saponin of Korean Red Ginseng (SKRG) decreased the expression of GM-CSF in UVB-irradiated SP-1 keratinocytes. In this study, we attempted to find the inhibitory mechanism of SKRG on UVB-induced GM-CSF expression in SP-1 keratinocytes.MethodsWe investigated the inhibitory mechanism of SKRG and ginsenosides from Panax ginseng on UVB-induced GM-CSF expression in SP-1 keratinocytes.ResultsTreatment with SKRG decreased the expression of GM-CSF mRNA and protein induced by irradiation of UVB in SP-1 keratinocytes. The phosphorylation of ERK was induced by UVB at 10 min, and decreased with SKRG treatment in SP-1 keratinocytes. In addition, treatment with SKRG inhibited the UVB-induced phosphorylation of epidermal growth factor receptor (EGFR), which is known to be an upstream signal of ERK. From these results, we found that the inhibition of GM-CSF expression by SKRG was derived from the decreased phosphorylation of EGFR. To identify the specific compound composing SKRG, we tested fifteen kinds of ginsenosides. Among these compounds, ginsenoside-Rh3 decreased the expression of GM-CSF protein and mRNA in SP-1 keratinocytes.ConclusionTaken together, we found that treatment with SKRG decreased the phosphorylation of EGFR and ERK in UVB-irradiated SP-1 keratinocytes and subsequently inhibited the expression of GM-CSF. Furthermore, we identified ginsenoside-Rh3 as the active saponin in Korean Red Ginseng.

The use of natural ingredients in innovative Korean cosmeceuticals

“…There was no noted cytotoxic effect of red ginseng extract on the keratinocyte cells. These results support the antitumor, antimetastatic, and antiangiogenic properties of ginsenosides . It was also found that combining ginseng extract with Trichosanthis kirilowii (another herb used in traditional Asian medicine) inhibits melanogenesis in melanoma cells lines by decreasing tyrosinase activity and thereby decreasing melanin content in cells …”

Photoaging protective effects of BIOGF1K, a compound-K-rich fraction prepared from Panax ginseng

“…In fact, numerous cosmetic products contain fractions previously prepared in Korea from P. ginseng (e.g., BG11001, P. ginseng berry, and AP-SF) [48] , [49] , [50] . Studies on individual compounds from P. ginseng have indicated that ginsenosides (G)-Rg2, G-F2, G-Re, and G-Rb2 protect skin and possess additional cosmeceutical activities by suppressing melanin biosynthesis, enhancing cyclic growth of hair follicles, improving skin barrier function, and suppressing skin inflammation [51] , [52] , [53] . Therefore, ginsenosides in BIOGF1K could contribute to its antiphotoaging activity, thereby increasing the value of this fraction as a cosmeceutical biomaterial.…”

Inhibitory effects of ginsenosides on basic fibroblast growth factor-induced melanocyte proliferation

“…Keratinocyte derived paracrine factors stimulate melanocyte proliferation, leading to skin hyperpigmentation [18] . In a previous study, we found that SKRG decreased GM-CSF expression levels in UV-B induced keratinocytes [44] and inhibited the proliferation of GM-CSF induced melanocytes [39] . These findings showed that SKRG had antiproliferative effects on mouse melanocytes and ginsenoside Rh3 and F1 may be effective ingredients that inhibit skin pigmentation stimulated by bFGF following UV-B radiation.…”