Plasma Pyridoxal-5-Phosphate Is Inversely Associated with Systemic Markers of Inflammation in a Population of U.S. Adults

Abstract

Low vitamin B-6 status, based on plasma concentrations of pyridoxal-5-phosphate (PLP), has been identified in inflammatory diseases, including cardiovascular disease, rheumatoid arthritis, inflammatory bowel disease, and diabetes. Our objective was to examine the association between plasma PLP and multiple markers of inflammation in a community-based cohort [n = 2229 participants (55% women, mean age 61 ± 9 y)]. We created an overall inflammation score (IS) as the sum of standardized values of 13 individual inflammatory markers. Multivariable-adjusted regression analysis was used to assess the associations between the IS and plasma PLP. Geometric mean plasma PLP concentrations were lower in the highest tertile category of IS relative to the lowest (61 vs. 80 nmol/L; P-trend < 0.0001). Similarly, the prevalence of PLP insufficiency was significantly higher for participants in the highest compared with the lowest tertiles for IS categories. These relationships persisted after accounting for vitamin B-6 intake. Also, there were significant inverse relationships between plasma PLP and 4 IS based on functionally related markers, including acute phase reactants, cytokines, adhesion molecules, and oxidative stress. In addition, secondary analyses revealed that many of the individual inflammatory markers were inversely associated with plasma PLP after adjusting for plasma C-reactive protein concentration. This study, in combination with past findings, further supports our hypothesis that inflammation is associated with a functional deficiency of vitamin B-6. We discuss 2 possible roles for PLP in the inflammatory process, including tryptophan metabolism and serine hydroxymethyltransferase activity.

Circulating Biomarkers of Tryptophan and the Kynurenine Pathway and Lung Cancer Risk

“…KTR showed positive associations with age and BMI as previously shown (33)(34)(35)(36)(37), and with neopterin, which can be explained by the fact that both neopterin and IDO are stimulated by INF-g (38)(39)(40). Both KTR and neopterin were negatively associated with PLP, which is in accordance with multiple observations of inflammation or immune activation in subject with low PLP status (41). We also observed an inverse association of KTR, and several kynurenines with cotinine, in line with published results (42), which may reflect the immunosuppressive effect from smoking (43).…”

Association of Low Baseline Levels of Erythrocyte Folate With Treatment Nonresponse at Three Months in Rheumatoid Arthritis Patients Receiving Methotrexate

“…However, earlier research showed that vitamin B 6 levels are inversely associated with systemic markers of inflammation (28). In addition, mild vitamin B 6 deficiency characterizes a subclinical at-risk condition in inflammation-related diseases (29).…”

Vitamin B6 Prevents IL-1β Protein Production by Inhibiting NLRP3 Inflammasome Activation

“…There is growing evidence that vitamin B6 has anti-inflammatory activity. Epidemiological evidence indicates that patients with inflammation have significantly lower blood levels of PLP than control subjects (1,2). In patients with rheumatoid arthritis, high-dose vitamin B6 supplementation (100 mg/day) suppresses plasma IL-6 and TNF-␣ levels (3).…”

“…The B6 vitamer pyridoxal 5Ј-phosphate (PLP) 2 is an essential cofactor for many enzymes involved in amino acid metabolism. There is growing evidence that vitamin B6 has anti-inflammatory activity.…”