Improved Vitamin B-6 Status Is Positively Related to Lymphocyte Proliferation in Young Women Consuming a Controlled Diet

• Published in: The Journal of nutrition Vol. 132; no. 11; pp. 3308 - 3313
• Main Authors: Kwak, Ho-Kyung, Leklem, James E., Hardin, Karin, Hansen, Christine M., Shultz, Terry D.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Bethesda, MD Elsevier Inc 01.11.2002; American Society for Nutritional Sciences; American Institute of Nutrition
• Subjects: 4-pyridoxic acid; administration & dosage; Adult; Alanine Transaminase; Alanine Transaminase - blood; Analysis of the immune response. Humoral and cellular immunity; Biological and medical sciences; biosynthesis; blood; Body Height; chemistry; Cytokines; Diet; enzymology; erythrocytes; Erythrocytes - enzymology; fasting; Female; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Immunobiology; interleukin 2; Interleukin-2 - biosynthesis; Interleukin-2 - blood; Leukocytes, Mononuclear; Leukocytes, Mononuclear - chemistry; lymphocyte; Lymphocyte Activation; lymphocyte proliferation; mononuclear leukocytes; Nutritional Status; Organs and cells involved in the immune response; peripheral blood mononuclear cells; pharmacology; phytohemagglutinin; Phytohemagglutinins; Phytohemagglutinins - pharmacology; proliferation; pyridoxal; Pyridoxal Phosphate; Pyridoxal Phosphate - blood; Pyridoxic Acid; Pyridoxic Acid - urine; pyridoxine; urine; Vitamin B; Vitamin B 6; Vitamin B 6 - administration & dosage; vitamin B-6 status; Women; young women; young women; peripheral blood mononuclear cells; proliferation; EALT; PHA; IL-2; B-6; PBMC; RDA; lymphocyte; 4-PA; interleukin 2; PLP; vitamin B-6 status; EAST; Ig; Human; Cell proliferation; Immune response; Cytokine; Cellular immunity; B-Vitamins; Pyridoxine; Supplemented diet; Feeding; Micronutrient; Interleukin 2; Young adult; T-Lymphocyte; Female; Nutritional status
• ISSN: 0022-3166; 1541-6100
• DOI: 10.1093/jn/132.11.3308

To examine the effect of increased intake levels of vitamin B-6 (B-6) on lymphocyte proliferation and interleukin 2 (IL-2) concentration, young women (n = 7) consumed a constant diet containing 1 mg (5.91 μmol) B-6/d for a 7-d adjustment period, followed by three 14-d experimental periods during which the daily B-6 intake was 1.5, 2.1 and 2.7 mg (8.86, 12.41 and 15.95 μmol)/d, respectively. Weekly fasting blood and daily 24-h urine samples were collected. Lymphocyte proliferation and IL-2 production were measured in response to phytohemagglutinin. Vitamin B-6 status improved with increased B-6 intake as measured by plasma pyridoxal 5′-phosphate (PLP) and urinary 4-pyridoxic acid. When subjects consumed 2.1 mg B-6/d for 7 d, lymphocyte proliferation increased by 35% (P ≤ 0.05) compared with the mean value after consumption of 1.5 mg B-6/d for 14 d. There was no further enhancement after an additional week of 2.1 and 2.7 mg B-6/d for 2 wk. Lymphocyte proliferation was correlated (P ≤ 0.01) with vitamin B-6 intake (r = 0.757), plasma PLP (r = 0.456) and erythrocyte aminotransferase activities (r = −0.361). Plasma IL-2 concentration and in vitro production did not change throughout the study, although five of seven subjects showed increases with intakes of 2.1 and 2.7 mg B-6/d, respectively, compared with the 1.5 mg/d intake. Concentrations of PLP in peripheral blood mononuclear cells were correlated (r = 0.357, P ≤ 0.01) with plasma PLP, but not with proliferation. These results show that improving vitamin B-6 status by consuming a B-6 intake higher than the current Recommended Dietary Allowance enhances lymphocyte proliferation.