AUTHOR=Paulin Fernanda Viana , Goelzer Leandro Steinhorst , Müller Paulo de Tarso 

TITLE=Vitamin B12 Supplementation and NT-proBNP Levels in COPD Patients: A Secondary Analysis of a Randomized and Controlled Study in Rehabilitation

JOURNAL=Frontiers in Neuroscience

VOLUME=14

YEAR=2020

URL=https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2020.00740

DOI=10.3389/fnins.2020.00740

ISSN=1662-453X

ABSTRACT=<sec><title>Purpose</title><p>There is evidence of complex interaction between vitamin B<sub>12</sub> (vB<sub>12</sub>) level, hyperhomocysteinemia (HyCy), and natriuretic peptide secretion. Exercise training could also modulate such interaction. In this secondary analysis of a Randomized Clinical Trial performed in a chronic obstructive pulmonary disease (COPD) rehabilitation setting, our primary objective was to investigate the interaction between vB<sub>12</sub> supplementation, exercise training, and changes in NT-proBNP levels after 8 weeks of intervention. Secondary objectives were to explore the correlations between acute changes in NT-proBNP levels with (i) acute exercise and (ii) oxygen uptake (<italic>V</italic>’O<sub>2</sub>) kinetics during rest-to-exercise transition.</p></sec><sec><title>Methods</title><p>Thirty-two subjects with COPD were randomized into four groups: Rehabilitation+vB<sub>12</sub> (<italic>n</italic> = 8), Rehabilitation (<italic>n</italic> = 8), vB<sub>12</sub> (<italic>n</italic> = 8), or Maltodextrin(<italic>n</italic> = 8). They were evaluated at baseline and after 8 weeks, during resting and immediately after maximal exercise constant work-rate tests (CWTs, <italic>T</italic>lim), for NT-proBNP plasmatic levels.</p></sec><sec><title>Results</title><p>After interaction analysis, the supplementation with vB<sub>12</sub> significantly changed the time course of NT-proBNP responses during treatment (<italic>p</italic> = 0.048). However, the final analysis could not support a significant change in NT-proBNP levels owing to high-intensity constant work-rate exercise (<italic>p</italic>-value &gt; 0.05). There was a statistically significant correlation between <italic>V</italic>’O<sub>2</sub> time constant and ΔNT-proBNP values (<italic>T</italic>lim – rest) at baseline (<italic>p</italic> = 0.049) and 2 months later (<italic>p</italic> = 0.015), considering all subjects (<italic>n</italic> = 32).</p></sec><sec><title>Conclusion</title><p>We conclude that vB<sub>12</sub> supplementation could modulate NT-proBNP secretion. Moreover, possibly, the slower the initial <italic>V</italic>’O<sub>2</sub> adjustments toward a steady-state during rest-to-exercise transitions, the more severe the ventricular chamber volume/pressure stress recruitment, expressed through higher NT-proBNP secretion in subjects with larger <italic>V</italic>’O<sub>2</sub> time constants, despite unchanged final acute exercise-induced neurohormone secretion.</p></sec>