Increased plasma VEGF levels in major depressive or manic episodes in patients with mood disorders

Background: The neurotrophic hypothesis suggests that mood disorders are associated with dysfunction of neuronal networks under the influence of neurotrophic factors. Vascular endothelial growth factor (VEGF) is a neurotrophic factor as well as an angiogenic cytokine. Methods: We examined plasma VEGF levels in 35 unipolar patients who were diagnosed with current major depressive disorder (MDD), 35 bipolar patients who were diagnosed with bipolar I disorder, manic episode (BM), and 60 healthy controls. The severity of depressive or manic symptoms was measured using the Hamilton Depression Rating Scale (HDRS) or the Young Mania rating scale (YMRS), respectively. Results: Plasma VEGF levels were 163.28 ± 135.33 pg/mL in MDD patients, 199.82 ± 182.59 pg/mL in BM patients, and 110.05 ± 109.57 pg/mL in healthy controls. Both MDD and BM patients had significantly higher VEGF levels than healthy controls when controlling for BMI as a covariate (p = 0.010). Patients' VEGF levels were not correlated with either HDRS or YMRS scores. Limitations: We assessed plasma VEGF levels at one time point, and we did not determine the source of VEGF in our samples. Conclusions: Plasma VEGF levels were elevated in patients with acute episodes of major depressive disorder and bipolar disorder. Such an alteration of VEGF in acute episode, mood disorders may be associated with a neuroprotective role for VEGF.