Immune system and nutraceuticals
A wide variety of nutraceuticals have been shown to impose crucial roles in immune status and susceptibility to some diseases conditions. Nutraceuticals that belong to the category of immune boosters are useful to improve immune function. They include extracts from the coneflowers, or herbs of the genus Echinacea, such as Echinacea angustfolia, Echinacea pillida, Echinacea purpurea. The coneflowers in particular are a popular herbal remedy used in the central United States, an area to which they are indigenous. Astragalus mongolicus, Astragalus membranaceus, and other herbs of the Astragalus genus are also effective immune boosters. Astragalus stimulates development and transformation of stem cells in the marrow and lymph tissue to active immune cells. Phytoestrogens mostly are recommended for prevention of various diseases related to hormonal imbalance. There is a special interest in soy isoflavones as potential superior alternatives to the synthetic selective estrogen receptor modulators, which are currently applied in hormone replacement therapy. Garlic and morphine also are good examples of the nutraceuticals, which respectively stimulate and suppress the immune system.
The effect of herbal medicines and bacteria on the immune system and intestinal epithelial cell function has led to new credence for the use of nutraceuticals and probiotics in clinical settings. Probiotics are effective in conditions such as infectious diarrhea in children and recurrent Clostridium difficile induced infections.
Supplementation with probiotics (live viable microbial organisms) may provide maturational signals for the lymphoid tissue and improve the balance of pro and antiinflammatory cytokines. Probiotics manipulate the intestinal microflora to maintain a normal balance between pathogenic and nonpathogenic bacteria. Usage of these agents in the treatment of specific diseases has evolved into the ability to have a very high index of safety, reduction of antibiotic use and the public’s positive perception about “alternative” or “natural” therapies. Most probiotic preparations consist of one or more lactic acid bacteria. Within this group, strains of Lactobacillus, Bifidobacterium sp. and occasionally Streptococcus are most commonly used.