Pyridoxine supplementation: effect on lymphocyte responses in elderly persons

Abstract

The effect of pyridoxine supplementation on lymphocyte responsiveness was investigated in 15 persons aged 65-81 y. Eleven subjects received 50 mg/d pyridoxine HCl (PN). Four subjects received a placebo. Lymphocyte proliferation to T and B cell mitogens, lymphocyte subpopulations with monoclonal antibodies, and plasma pyridoxal 5'-phosphate (PLP) were measured before and after 1 and 2 mo of supplementation. After 1 and 2 mo plasma PLP levels increased by 195 +/- 88 nM and 201 +/- 84 nM, respectively, in subjects receiving PN. With PN supplementation, lymphocyte proliferation increased significantly in response to phytohemagglutinin (p less than 0.01), pokeweed mitogen (p less than 0.01), and Staphylococcus aureus (Cowain I) (p less than 0.05). For PN-treated subjects with low presupplement plasma PLP levels, lymphocyte blastogenesis also increased significantly (p less than 0.01) in response to concanavalin A. Percentages of T3+ and T4+ but not T8+ cells increased significantly (p less than 0.05) in PN-treated subjects. These results suggest that improving vitamin B-6 status is important in stimulating immunocompetence in the elderly.

Vitamin B6 supplementation increases immune responses in critically ill patients

“…In the present study, our critically ill patients had abnormal immune responses even though their vitamin B 6 intake was higher than Taiwan DRI recommendations (Department of Health, Taiwan, 2002) on the first day of admission to the ICU. In agreement with the previous studies (Casciato et al, 1984;Talbott et al, 1987;Folkers et al, 1993), several cellular immune response parameters (i.e., T lymphocyte, T-helper and T-suppressor cells) significantly increased after the supplementation of either 50 or 100 mg/day of vitamin B 6 for 14 days; whereas immune responses showed no significant changes in the control group. This suggests that vitamin B 6 supplementation could increase immune responsiveness of only T cells but not B cells.…”

“…However, the effect of vitamin B 6 supplementation on immune responses in immunocompromised subgroups within the population (i.e., elderly, ill patients) has been seldom reported. Only a few studies have shown that 50-300 mg/day vitamin B 6 supplementation in either healthy elderly or hemodialysis patients significantly improved immune responses of subjects (Casciato et al, 1984;Talbott et al, 1987;Folkers et al, 1993). In the present study, our critically ill patients had abnormal immune responses even though their vitamin B 6 intake was higher than Taiwan DRI recommendations (Department of Health, Taiwan, 2002) on the first day of admission to the ICU.…”

“…This suggests that vitamin B 6 supplementation could increase immune responsiveness of only T cells but not B cells. The increase in the percentage of T3 þ and T4 þ cells has been suggested to affect the differentiation of immature T cells to mature T cells by vitamin B 6 supplementation in healthy elderly (Talbott et al, 1987). In the study of Gray et al (2004), patients who underwent an elective knee arthroplasty had a significant increase in circulatory CRP concentrations and there was a significant fall in plasma PLP concentration but red cell PLP remained stable.…”

“…Casciato et al (1984) indicated that eight hemodialysis patients supplemented with 50 mg/day of vitamin B 6 (pyridoxine hydrochloride (HCl)) for 3-5 weeks showed an improvement in their nitroblue tetrazolium reduction test, the generation of chemotactic factors from plasma, lymphocyte subpopulation and lymphocyte transformation in response to mitogens. Lymphocyte proliferation significantly increased in response to phytohemagglutinin, pokweweed and Staphylococcus aureus after 11 healthy elderly were supplemented with 50 mg/day of vitamin B 6 (pyridoxine) for 2 months; Talbott et al (1987), therefore, indicated that increasing vitamin B 6 intake could improve immune responsiveness of both T and B cells. Folkers et al (1993) treated nine healthy subjects with 300 mg/day of pyridoxine, consequently their T4 lymphocytes and T4/T8 ratio significantly increased over 2 months.…”

Vitamin B6 intakes and status of mechanically ventilated critically ill patients in Taiwan

“…Critical clinical conditions and complex metabolism in the critically ill may account for the reduction of plasma PLP and PL. Since vitamin B6 is required for normal nucleic acid and protein synthesis and for cellular multiplication, vitamin B6 deficiency causes profound effects on immune system function (Axlerod 1971;Talbott et al, 1987). Dietary or supplemented vitamin B6 intake is suggested for hospitalized patients.…”