Association of plasma brain-derived neurotrophic factor levels with depressive disorder

Abstract:

Objective：To explore the correlation between the plasma levels of brain-derived neurotrophic factor （BDNF） and depres－sion. Methods：Enzyme-linked immunosorbent analysis（ELISA） was used to test the plasma BDNF levels in 60 depressive patients and 30 normal controls. Meanwhile，the subjects were assessed with the Hamilton depression scale（HAMD） and Beck Self-rating De－pression Scale（BDI）. Results：The plasma levels of BDNF in depressive patients（931.10±250.04） pg/ml was significantly lower than those of normal controls（1 348.06±192.67） pg/ml（t=-8.013，P=0.000）. The plasma BDNF levels in recurrent depressive patients（1 007.57±277.52） pg/ml was lower than those of first-episode depressive patients（854.63±195.15） pg/ml（t=2.469，P=0.017）. There was no difference in HDRS total score（t=1.009，P=0.317），BDI total score（t=1.743，P=0.087） and plasma BDNF levels（t=-0.281，P=0.779） between early-onset depressive patients and late-onset depressive patients. Depressive patients with suicidal tendency had higher HDRS total score（t=3.917，P=0.000） and BDI total score（t=3.482，P=0.001） than depressive patients without suicidal tendency. The plasma BDNF levels were significantly lower in depressive patients with suicidal tendency than in depressive patients without sui－cidal tendency（（778.88±230.71） pg/ml vs. （1055.64±191.00） pg/ml，t=-5.085，P=0.000）. The plasma BDNF level was significant－ly negatively correlated with HDRS total score and BDI total score in depressive patients. Conclusion：The alteration of plasma BDNF level is related to depression and suicide，and it maybe involved in pathophysiology of depression and suicidal behavior.