Incluyo un articulo interesante sobre esta actividad de sinergismo en el estimulo de una mejor respuesta inmune, especialmente en las celulas naturalmente asesinas ,NKC, cuya actividad esta al máximo entre los 30 y 35 años y tiende a decaer con los años o situaciones criticas de inmunosupresión.
β-Carotene and selenium supplementation enhances immune response in aged humans
Steven M. Wood PD, RDa, Carla Beckham BA, BS, SM1, , b, Ayako Yosioka PD2, , b, Hamid Darban PD, CCP3, , b and Ronald R. Watson PD, , b
a Committee of Nutritional Sciences, University of Arizona, Tucson, AZ, USA
b College of Public Health, University of Arizona, Tucson, AZ, USA
Available online 14 September 2000.
Background: Nutritional research has focused on the effects of specific nutrients' ability to cause or prevent cancer. While β-carotene and selenium (both important for antioxidant systems) have cancer prevention capabilities, their antineoplastic mechanism(s) remains to be elucidated. Methods: In a prospective, randomized study design we evaluated immunological changes in free-living, healthy aged humans (57–84 years of age) given a placebo, β-carotene (45 mg/day), and/or selenium (400 μg/day) supplement for 6 months and after 2 months of discontinuation. Peripheral blood lymphocytes were evaluated and subtyped using flowcytometry. Natural killer (NK) cell cytotoxicity was determined by a fluorescent method. Plasma diene conjugates were assessed to evaluate changes in oxidative stress. Results: Selenium and selenium plus β-carotene supplementation caused an increase in total T cells by 27% and 31%, respectively (p < .05). The only group that was different (in T lymphocytes) from the controls (placebo group) after 6 months of supplementation (p < .05) was the selenium-supplemented group (+65%). Much of this increase was the result of an increase in CD4+ T-cell subsets. Selenium or β-carotene supplementation for 3 months increased NK cell cytotoxicity over pretreatment levels by 58% and 34%, respectively; however, these levels returned to +12% and −6% of pretreatment levels after 6 months supplementation. Selenium plus β-carotene supplementation caused an increase in the percentage of NK cell by 121% and 161% at 3 and 6 months, respectively. However, the increased numbers of NK cells were not correlated with NK cell activity. Conclusions: We found that selenium enhanced immune function (NK cell cytotoxicity) and phenotypic expression of T-cell subsets, whereas β-carotene affected only immune function. Increased NK cell cytotoxicity may last for only a short period of supplementation and was not sustained throughout the 6 months of supplementation. Supplemental selenium and β-carotene seemed to affect immune function in aged subjects by different mechanisms.
Author Keywords: β-carotene; selenium; aged; immune function
1 Current address: Biogen Inc., 12 Cambridge Center, Cambridge, MA 02142, USA.
2 Current address: Shokei-Gakuen University, Department of Domestic Sciences, Kumamoto, Japan.
3 Current address: Duquesne University, Department of Clinical Sciences, 125 Health Sciences Building, Pittsburgh, PA 15282, USA.
Address reprint requests to: Dr. Ronald R. Watson, Professor of Public Health Research, PO Box 245155, 1501 N. Campbell Ave., University of Arizona School of Medicine, Arizona Health Science Center, Tucson, AZ 85724, USA; Fax: (520) 626-6093; email: email@example.com