Immune Modulating Effects of Daily Supplementation of COLD-fX (a Proprietary Extract of North American Ginseng) in Healthy Adults

Abstract

In a previous study, COLD-fX (CVT-E002), a proprietary extract of the root of North American ginseng (Panax quinuefolium), was found effective in the prevention of upper respiratory tract infections (URIs) in healthy adults. The underlying mechanisms of its action, however, were not determined. The present study was carried out to explore if the effects observed could be due to COLD-fX-mediated changes in the distribution of peripheral blood leukocytes, changes in the relative distribution of lymphocyte subsets or IgA levels in plasma. At the onset of an influenza season, a total of 323 subjects between 18 and 65 years with a history of more than 2 colds in the previous year, participated in a randomized double-blind placebo-controlled study. The participants were instructed to take 2 capsules/day of either COLD-fX or placebo for a period of 4 months. Two blood samples were collected from 42 (COLD-fX = 21; placebo = 21) of the 323 recruited volunteers. These samples were obtained before and after the treatment, and were used for determination of white blood cell differential counts, enumeration of lymphocyte subsets and measurement of plasma levels of immunoglobulin A (IgA). The distribution of colds over the 4 month period was found to be similar in both treatment and placebo groups. However although non-significant, the severity of the colds in the COLD-fX group was found to decrease over time. COLD-fX intervention increased the proportion of T-helper and natural killer (NK) cells, and decreased IgA levels in plasma to a greater extent than the placebo. It is possible, therefore, that these cells acted synergistically to reduce the severity and duration of URIs in the COLD-fX group. Further studies are warranted to determine the effects of daily supplementation of COLD-fX on the activities of T-helper and NK cells in plasma.

Stimulation and Suppression of Innate Immune Function by American Ginseng Polysaccharides: Biological Relevance and Identification of Bioactives

“…AGRPS and AQ extracts are not antagonists of LPS because they have low stimulatory effect and also requires pretreatment before they can suppress LPS stimulation. The data from this study supports the reported CVT-E002 TM immunostimulatory [22,29,48,[59][60][61][62] and suppression of proinflammatory effects [21,63] under basal and induced proinflammatory conditions respectively. Therapies directed at the neutralization of proinflammatory mediators Fig.…”

“…The ex vivo, in vivo and in vitro studies support the observations from our previous study, indicating that bioactive AGRPS isolated from AQ extract and its parent AQ extract exerted immunostimulatory effects [32]. The in vivo immunostimulatory effect of 125 mg/kg AGRPS and AQ extracts was very small as compared with 5 mg/kg LPS toxic stimulatory effect, suggesting that American ginseng extract and its natural health product containing polysaccharides like CVT-E002™ are safe with health benefits with regards to immunostimulation [48]. The results from this study suggests that under LPS mediated excessive stimulatory infectious condition like endotoxemia; pretreatment with AGRPS and AQ extracts will not cause additive immunostimulatory effects, but rather the extracts will reduce and neutralize LPS immunologic stimulatory effect.…”

“…Polysaccharides, incluing lentinan, a (1,3)-β-D-glucan, isolated and purified from Lentinus edodes has been licensed as an over-thecounter (OTC) dietary supplement and immunostimulatory drug in China [47]. In Canada, CVT-E002™ (sold commercially as COLD-FX®) a poly-furanosyl-pyranosyl polysaccharide-rich herbal product of the root of American ginseng was licensed in 2007 as a natural health product to 'help reduce the frequency, severity and duration of cold and flu symptoms by boosting the immune system' [21,48].…”

Bioactive Polysaccharides of American Ginseng Panax quinquefolius L. in Modulation of Immune Function: Phytochemical and Pharmacological Characterization

“…And a few polysaccharides, including lentinan, Astragalus polysaccharide, polyporus polysaccharide and Achyranthes bidentata polysaccharide have been licensed for clinical application in China [16]. In Canada, a polysaccharide-enriched American ginseng extract (Cold Fx®) has been licensed in 2007 as a natural health product to 'help reduce the frequency, severity and duration of cold and flu symptoms by boosting the immune system' with an estimated annual sale of over $48M [4,5]. Our findings on the paradoxical effects of AQ and PS extract on macrophage function in vivo may have significant implication in the use of American ginseng polysaccharides in several clinical applications.…”

“…Specifically, the polysaccharide fraction of ginseng has been shown to have immunomodulatory effects in both preclinical and clinical studies [3][4][5][6], although they are poorly characterized.…”