Abstract
It is well known that Panax ginseng (PG) has various pharmacological effects such as anti-aging and anti-inflammation. In a previous study, the authors identified that PG extract induced hair growth by means of a mechanism similar to that of minoxidil. In the present study, the inhibitory effect of PG extract on Dickkopf-1 (DKK-1)-induced catagen-like changes in hair follicles (HFs) was investigated in addition to the underlying mechanism of action. The effects of PG extract on cell proliferation, anti-apoptotic effect, and hair growth were observed using cultured outer root sheath (ORS) keratinocytes and human HFs with or without DKK-1 treatment. The PG extract significantly stimulated proliferation and inhibited apoptosis, respectively, in ORS keratinocytes. PG extract treatment affected the expression of apoptosis-related genes Bcl-2 and Bax. DKK-1 inhibited hair growth, and PG extract dramatically reversed the effect of DKK-1 on ex vivo human hair organ culture. PG extract antagonizes DKK-1-induced catagen-like changes, in part, through the regulation of apoptosis-related gene expression in HFs. These findings suggested that PG extract may reduce hair loss despite the presence of DKK-1, a strong catagen inducer via apoptosis.