Panax ginseng as a potential modulator of macrophages

Abstract

Bacteria-induced sepsis is a medical emergency requiring immediate intervention; the key to prevent sepsis is to prevent an infection from occurring in the first place. Although Panax ginseng (Korean ginseng) has been well known as an immune modulator, its role in bacterial sepsis is not well understood. Using RAW 264.7 macrophages and a murine model, we elucidated the protective effect of P. ginseng against community-associated Streptococcus pneumoniae (pneumococcus)-induced sepsis via inhibition of inflammation. In pneumococcal infections, pre-treatment with P. ginseng decreased the expressions of Toll-like receptor 4 (TLR4) and tumor necrosis factor (TNF)-ɑ in RAW 264.7 macrophages, but increased the expression of phosphoinositide 3-kinase (PI3K) and AKT kinase, thereby enhancing cellular viability. Furthermore, secretion of pro-inflammatory cytokines (TNF-ɑ and interleukin (IL)-1β) as well as neutrophil infiltration was diminished by pre-treatment with P. ginseng. As a result, mice pre-treated with P. ginseng demonstrated significantly higher survival rate and body weight gain than the non-treated mice (control). Treated mice showed diminished colonization of bacteria and morbidity. In addition, some studies have indicated that P. ginseng or ginseng compounds activated macrophage functions, which supports the immune system against cancer and other diseases. In the present study, we will discuss dual roles of P. ginseng in modulating macrophage functions.