Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Critical Care giúp cho các bạn có thêm kiến thức về ngành y học đề tài: The Yin and Yang actions of North American ginseng root in modulating the immune function of macrophages. | Azike et al. Chinese Medicine 2011 6 21 http content 6 1 21 CHINESE MEDICINE RESEARCH Open Access The Yin and Yang actions of North American ginseng root in modulating the immune function of macrophages Chike Godwin Azike Paul Abrahams Charpentier Jirui Hou Hua Pei and Edmund Man King Lui Abstract Background Immuno-modulatory effects of ginseng including both immuno-stimulatory and immunosuppressive effects have been widely reported. This study aims to determine whether the paradoxical immunomodulatory effect is related to unique phytochemical profiles of different North American NA ginseng namely aqueous AQ and alcoholic ALC extracts. Methods AQ and ALC extracts were prepared and their immuno-bioactivity were studied in vitro in murine macrophages Raw through measuring the direct stimulatory production of pro-inflammatory mediator and cytokines as well as the suppression of lipopolysaccharide LPS -stimulatory response by the two extracts. Gel permeation chromatography was used to fractionate and isolate phytochemicals for characterization of ginseng extracts. Results AQ extract up-regulated the production of nitric oxide NO tumour necrosis factor-a TNF-a and interleukin-6 IL-6 while ALC extract did not. ALC extract but not AQ extract suppressed LPS-induced macrophage NO and TNF-a production. These immuno-stimulatory and suppressive effects were exhibited at similar extract concentrations. Moreover the macrophage-stimulating activity of the AQ extract was inhibited in the presence of ALC extract. Fractionation of AQ extract revealed the presence of two major peaks at 230 nm with average molecular weights of 73 000 and 37 000 Da. The first fraction had similar elution volume as the crude polysaccharide PS fraction isolated from the AQ extract and it was the only bioactive species. Parallel fractionation study of ALC extract yielded similar elution profiles however both sub-fractions were devoid of PS. Fraction I of the ALC
