Stress at work alters serum brain-derived neurotrophic factor (BDNF) levels and plasma 3-methoxy-4-hydroxyphenylglycol (MHPG) levels in healthy volunteers: BDNF and MHPG as possible biological markers of mental stress?

There is growing evidence that blood levels of brain-derived neurotrophic factor (BDNF) and catecholamine, and cytokines are related to not only to depressive, suicidal, and anxious states but also to depression-associated personality traits. Psychological job stress is well known to lead to symptoms of depression and anxiety. In the present study, we examined effects of psychological job stress on serum levels of BDNF and plasma levels of catecholamine metabolites, and cytokines in healthy volunteers (n=106, male/female=42/64, age=36+/-12 yr) working in a hospital setting. The values (mean+/-SD) of scores for stress items in the Stress and Arousal Check List (s-SACL), plasma MHPG levels, and, serum BDNF levels in all participants were 7.2+/-3.3, 5.2+/-3.4 ng/mL, and 23.3+/-14.7 ng/mL, respectively. A negative correlation was found between scores for s-SACL and serum BDNF levels (rho=-0.211, p=0.022). A positive correlation was also found between scores on the s-SACL and plasma levels of 3-methoxy-4-hydroxyphenylglycol (MHPG) (rho=0.416, p=0.01), but not homovanillic acid (HVA). No relationship was found between s-SACL scores and plasma levels of interleukin-6 (IL-6) or tumor necrosis factor alpha (TNFalpha). These results suggest that serum BDNF levels and plasma MHPG levels might be biological markers reflective of psychological job stress in hospital employees.