Vitamin B − 6 deficiency impairs interleukin 2 production and lymphocyte proliferation in elderly adults

Abstract

The effect of vitamin B-6 deficiency on immune response was studied in eight healthy elderly adults. The protocol consisted of a 5-d baseline (BL) period; a vitamin B-6-depletion period of less than or equal to 20 d; three stages of vitamin B-6-repletion, each lasting 21 d; and a 4-d final phase. The amounts of vitamin B-6 ingested during the different phases of the study were 3.00, 15.00, 22.50, and 33.75 micrograms.kg body wt-1.d-1, respectively. During the final phase the subjects ingested 50 mg vitamin B-6/d. Fasting blood was collected at the end of each period. Vitamin B-6 depletion significantly decreased percentage and total number of lymphocytes, mitogenic responses of peripheral blood lymphocytes to T- and B-cell mitogens, and interleukin 2 production. These indices returned to BL values after the third vitamin B-6-repletion period, when the total vitamin B-6 intakes were 1.90 +/- 0.18 mg/d for women and 2.88 +/- 0.17 mg/d for men. Vitamin B-6 deficiency impairs in vitro indices of cell-mediated immunity in healthy elderly adults. This impairment is reversible by vitamin B-6 repletion.

The prevalence and risk factors for age-related macular degeneration in rural–urban India, Sankara Nethralaya Rural–Urban Age-related Macular degeneration study, Report No. 1

“…The supplementation was more effective in those subjects with the lowest initial plasma pyridoxal phosphate levels, indicating that higher than RDA levels of B6 might be needed to achieve optimal immune responsiveness in older persons. This is supported by the study by Meydani et al (122) who, using a B6 depletionrepletion protocol, showed that IL-2 production and mitogenic response to T and B cell mitogens by peripheral blood mononuclear cells of older subjects are influenced by changes in dietary vitamin B6 levels. In this study, biochemical measures of vitamin B6 status returned to normal at dosages of 1.90-1.96 mg/day.…”

Vitamin B6: a challenging link between nutrition and inflammation in CVD

“…Low vitamin B 6 concentrations could thus reflect an increased consumption of PLP in the accelerated synthesis of cytokines (76) and in the activation and proliferation of lymphocytes, both of which are key events in the inflammatory process (77,78) . Considering the epidemiological evidence of a role of vitamin B 6 in inflammatory-related diseases and the observed relationship with inflammatory markers (11,16,18,79) , it is plausible that vitamin B 6 plays a role in CVD pathogenesis through mechanisms linked to inflammation (Table 4).…”

Vitamin B6 supplementation improves pro-inflammatory responses in patients with rheumatoid arthritis

“…Hussein et al (2008) also found a high CD4 þ /CD8 þ T-cell ratio in RA patients. Low plasma PLP concentrations have been related to alteration of immune responses, including impairment of both humoral and cell-mediated immunity (Meydani et al, 1991(Meydani et al, , 1992Rall and Meydani, 1993). In turn, reduced plasma PLP levels may alter immunological functions.…”