Ginsenoside Rg1 ameliorates psoriasis-like skin lesions by suppressing proliferation and NLRP3 inflammasomes in keratinocytes.

As a common chronic skin disease, psoriasis is characterized by the involvement of congenital acquired inflammatory immune diseases. In the study, our results indicated the effect of ginsenoside Rg1 on psoriasis-like skin and the potential protection mechanisms that have not yet been investigated. In vivo, psoriasis-like skin mice model was induced by imiquimod (IMQ), then was treated by ginsenoside Rg1 for consecutive 4 weeks to evaluate its effect, respectively. In vitro, M5 cocktail treatment of human immortalized keratinocyte HaCaT-induced psoriasis-like skin cell model, which was exposed to ginsenoside Rg1. The inflammatory cell infiltration, expression level of keratinocyte proliferation marker Ki67, keratinocyte proliferation, inflammatory cytokines, and ROS/NLRP3 pathway-related proteins in vivo and in vitro were examined by hematoxylin and eosin, immunohistochemistry, ELISA, CCK-8, flow cytometry, and western blot. All results demonstrated that ginsenoside Rg1 attenuated the injury of psoriasis-like skin, which inhibited the proliferation of skin keratinocytes and the activation of NLRP3 inflammasome and the level of inflammatory factors such as IL-1β and IL-18, and decreased the level of Ki67, NLRP3, and caspase-1 in mice and HaCaT. Furthermore, NLRP3 overexpression attenuates the effect of ginsenoside Rg1 on M5 cocktail-induced proliferation and NLRP3 inflammasomes in HaCaT. These results demonstrated that ginsenoside Rg1 could suppress the ROS/NLRP3 pathway to treat psoriasis-like skin. PRACTICAL APPLICATIONS: This is the very first study to explore the efficacy of ginsenoside Rg1 against psoriasis-like skin lesions to reveal the underlying mechanism. In this paper, the detection of skin histopathological analysis, CCK-8, flow cytometry, western blot, and ELISA analysis shows that ginsenoside Rg1 has preventive effect on psoriasis caused by imiquimod or M5 cocktail through inhibiting NLRP3 inflammasome, which helps in the development of novel nutraceutical/functional food against psoriasis and thus could improve the quality of life in psoriasis patients.