This review highlights the most important characteristics and possible applications of AG. Among numerous studies AG was documented to exert beneficial activity towards nervous system. It boosts memory, increases calmness, and enhances cognitive performance . It has therapeutic potential in treatment of Alzheimer disease and anxiety [64,66]. It also affects cardiovascular system—changes cardiac structure in hypertension, reduces heart rate, inhibits hypertrophy and heart failure [79,81,128,170]. Furthermore, AG prevents oesophageal damage resulted from reflux oesophagitis and formation of ulcer in gastric mucosa [84,85]. Apart from that, it displays antimicrobial activity against different pathogenic strains of bacteria including resistant to antibiotics S. aureus strain . AG is extensively investigated in terms of anti-cancer activity. It promotes apoptosis of cancer cells and alters many different signalling pathways important for cancer transformation [92,93,94,95,96,97,98,171]. It also protects normal cells from unwanted side effects of anti-cancer drugs and diminishes cancer-related fatigue [100,110]. However, the mechanisms underlying beneficial activity of AG in cancer is not fully understood. Administration of AG may be beneficial for individuals suffering from obesity and diabetes. It enhances sensitivity of tissues to insulin and inhibits formation of adipose tissue. Also, polysaccharides of AG were reported to display pro-health effects by stimulating the immune system. Assinewe et al. observed that polysaccharide of AG extract containing glucose, galactose, arabinose, rhamnose, and mannose displayed cytokine-stimulating activity on macrophages. In this study, aqueous extracts of AG roots (1–100 μg/mL) stimulated the release of immunoreactive TNF, contributing to the activation of macrophages . Yu et al. also showed immunostimulatory effect of the fraction of polysaccharide present in AG extract (50–400 μg/mL). AG extract application led to enhancement of splenic lymphocyte proliferation, macrophage phagocytosis and nitric oxide production . AG extract (125 mg/kg for 3–6 days) stimulated alveolar macrophages in rats associated with increased level of NO, TNF-α and IL-6 in plasma . These results were in agreement with those obtained by Azike. Similarly, AdG water extract (125 mg/kg) administered to rats for 3–6 days upregulated nitric oxide, TNF-α and IL-6. Within in vitro study macrophages were incubated with different concentrations of AG. A dose-dependent immunostimulatory activity of aqueous and alcohol extracts of AG (50–200 μg/mL) in rat macrophages was observed and an in vitro effect was more pronounced than corresponding in vivo result due to relatively low bioavailability of the extract administrated orally . As the methodology of AG separation is poorly developed, it is a promising direction for the future research.
Aging is a complicated process with multiple modulations occurring at many levels, from the molecular to the cells. Ginseng, an ancient Chinese herb widely used in Eastern medicine, has been studied for its anti-aging properties., and has been shown to have beneficial effects with regards to anti-inflammation, anti-oxidation, cardiovascular regulation, neurological improvement, anti-tumor, skin protection and immune modulation.
While ginseng did not appear to significantly increase the change in fatigue scores over placebo at 4 weeks (14.4 vs 8.2; P=.07), fatigue scores at 8 weeks were significantly improved (20 vs 10.3; P=.003). Interestingly, though, there was a significant improvement in fatigue scores with ginseng at both 4 weeks (P=.02) and 8 weeks (P=.01) when researchers looked at only those patients who were currently receiving cancer treatment. On the other hand, those patients who were not currently undergoing treatment did not show a significant improvement at either time cutoff.
The mechanism by which American ginseng may be able to moderate fatigue is evidenced by preclinical data. Several investigators have established a consistent link between CRF and inflammation and have provided data to support dysregulation of the hypothalamic pituitary adrenal axis (42–46). These data suggest that chronic fatigue in cancer is associated with an inability for the hypothalamic pituitary adrenal axis to regulate inflammatory processes and that concentrations of inflammatory cytokines remain elevated instead of reachieving homeostasis (42–46). Preclinical data evaluating the biologic activity of ginseng have demonstrated the ability of ginseng to downregulate inflammatory pathways (47), decrease inflammation (26–28), and modulate cortisol and the impact of chronic stress on the hypothalamic pituitary adrenal axis (27).