A comparative study on immune-stimulatory and antioxidant activities of various types of ginseng extracts in murine and rodent models

Abstract

Background: Ginseng (Panax ginseng) is a widely used traditional herbal supplement that possesses various health-enhancing efficacies. Various ginseng products are available in market, especially in the Korean peninsula, in the form of drinks, tablets, and capsules. The different ginseng types include the traditional red ginseng extract (RGE), white ginseng, and black red ginseng extract (BRGE). Their fermented and enzyme-treated products are also available. Different treatment regimens alter the bioavailability of certain compounds present in the respective ginseng extracts. Therefore, in this study, we aimed to compare the antioxidant and immune-stimulating activities of RGE, BRGE, and fermented red ginseng extract (FRGE).

Methods: We used an acetaminophen-induced oxidative stress model for investigating the reduction of oxidative stress by RGE, BRGE, and FRGE in Sprague Dawley rats. A cyclophosphamide-induced immunosuppression model was used to evaluate the immune-stimulating activities of these ginseng extracts in BALB/c mice.

Results: Our results showed that most prominently, RGE (in almost all experiments) exhibited excellent antioxidant effects via increasing superoxide dismutase, catalase, and glutathione peroxidase activities in the liver and decreasing serum 8-hydroxy-2'-deoxyguanosine, aspartate aminotransferase, and lactate dehydrogenase levels compared with the groups treated with FRGE and BRGE. Moreover, RGE significantly increased the number of white blood cells, especially T and B lymphocytes, and antibody-forming cells in the spleen and thymus, and it also activated a number of immune cell subtypes.

Conclusion: Taken together, these results indicate that RGE is the best supplement for consumption in everyday life for overall health-enhancing properties.

Keywords: Antioxidant; Black red ginseng extract; Fermented red ginseng extract; Immune stimulation; Red ginseng extract.

Fig. 1

Effects of RGE, BRGE, and FRGE on oxidative and hepatic pathological parameters. (A) SOD activity in NC group as compared to the normal group, †p < 0.01 and SOD activity in RGE- and FRGE-treated groups compared to the control group (NC), ^*p < 0.05. (B) CAT activity as compared to the normal group, †p < 0.01 and CAT activity in the RGE- and BRGE-treated groups compared to the control group (NC), ^*p < 0.05. (C) GPx activity as compared to the normal group, †p < 0.01 and GPx activity in RGE-, BRGE-, and FRGE-treated groups compared to the control group (NC), ^*p < 0.05. (D) 8-OHdG activity as compared to the normal group, †p < 0.01 8-OHdG levels in the RGE-treated group compared to the control group (NC) (*) and BRGE- and FRGE-treated groups (#), ^*#p < 0.05. (E) AST levels in the control group (NC) compared to the normal group, †p < 0.01 and AST level in the RGE-treated group compared to the control group (NC), ^∗p < 0.05. (F) ALT levels in the control group (NC) compared to the normal group, †p < 0.01. (G) LDH levels in the control group (NC) compared to the normal group, †p < 0.01 and LDH levels in RGE-treated group compared to the control group (NC), ^*p < 0.05. 8-OHdG, 8-hydroxy-2′-deoxyguanosine; ALT, alanine aminotransferase; APAP, acetaminophen; AST, aspartate aminotransferase; BRGE, black red ginseng extract; CAT, catalase; FRGE, fermented red ginseng extract; GPx, Glutathione peroxidase; LDH, lactate dehydrogenase; RGE, red ginseng extract; SOD, superoxide dismutase.

Fig. 2

Effects of RGE, BRGE, and FRGE on antibody-forming cells (AFCs) and splenic subpopulation in BALB/c mice treated with CY. (A) Decrease in splenocytes (x10⁸) from the normal group at **p < 0.01. Increase in splenocytes (x10⁸) in the RGE- and BRGE-treated groups compared with the CY control at ^#p < 0.05. (B) Decrease in AFCs (x10³)/spleen from the normal group at **p < 0.01, increase in AFCs (x10³)/spleen in the RGE-, BRGE-, and FRGE-treated groups compared with the CY control at ^##p < 0.01, and $ significantly less than RGE at p < 0.05. (C) Decrease in AFCs (x10⁶)/spleen from the normal group at **p < 0.01, increase in AFCs (x10⁶)/spleen in the RGE-, BRGE-, and FRGE-treated groups compared with the CY control at ^##p < 0.01, and $ significantly less than RGE at p < 0.05. (D) Decrease in the number of T-lymphocytes compared with the normal group at **p < 0.01, whereas increase in the number of T-lymphocytes in RGE- and FRGE-treated groups compared with the CY control at ^#p < 0.05 and ^##p < 0.01 and $ significantly less than RGE at p < 0.05. (E) Decrease in the number of B lymphocytes compared with the normal group at **p < 0.01, whereas increase in the number of B lymphocytes in RGE- and FRGE-treated groups compared with the CY control at ^##p < 0.01 and $ significantly less than RGE at p < 0.05. BRGE, black red ginseng extract; CY, cyclophosphamide; FRGE, fermented red ginseng extract; RGE, red ginseng extract.

Fig. 3

Effects of RGE, FRGE and BRGE on immune cell subtypes from thymus tissue. (A, B) Absolute number of CD4⁺CD8⁺ cells from thymus tissue for RGE group as compared with CY group at *p < 0.01 by FACS analysis. (C, D) Absolute number of CD4⁺CD25⁺ cells from thymus tissue for RGE group as compared with CY group at *p < 0.01 by FACS analysis. Bar graphs are representative of three independent experiments. BRGE, black red ginseng extract; CY, cyclophosphamide; FACS, fluorescent antibody cell sorting; FRGE, fermented red ginseng extract; RGE, red ginseng extract.

Fig. 4

Effects of RGE, FRGE, and BRGE on neutrophil migration assay and serum levels of antiinflammatory cytokines. (A) Chemotaxis of neutrophils from RGE-treated and FRGE-treated group as compared to CY-treated group at ^**p < 0.05. (B) Serum levels of IL-12 in RGE group as determined by ELISA when compared to CY-treated group at ^*p < 0.01. (C) Serum levels of IL-4 in RGE, FRGE, and BRGE groups as determined by ELISA when compared to CY-treated group at ^**p < 0.05. (D) Serum levels of IFN-γ in RGE and FRGE groups as determined by ELISA when compared to CY-treated group at ^**p < 0.05. Bar graphs are representative of three independent experiments. BRGE, black red ginseng extract; CY, cyclophosphamide; FRGE, fermented red ginseng extract; IFN, interferon; IL, interleukin; RGE, red ginseng extract.