Decreased plasma neurotrophin-4/5 levels in bipolar disorder patients in mania

Abstract

Objective: To evaluate two poorly explored neurotrophins (NT), NT-3 and NT-4/5, in bipolar disorder (BD). Methods: Forty patients with type I BD (18 in remission and 22 in mania) and 25 healthy controls matched for age, gender, and educational attainment were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatric Interview; the Young Mania Rating Scale and the Hamilton Depression Rating Scale were used to evaluate severity of symptoms in BD patients. Plasma levels of NT-3 and NT-4/5 were measured by enzyme-linked immunosorbent assay (ELISA). Results: BD patients in mania presented decreased NT-4/5 plasma levels in comparison with controls (p , 0.05). There were no significant differences in NT-3 plasma levels between BD patients and controls. Conclusion: These findings corroborate the view that neurotrophin dysfunction is associated with mood states in patients with BD.

Neurobiology of bipolar disorders: a review of genetic components, signaling pathways, biochemical changes, and neuroimaging findings

“…105 Another clinical study showed that NT-3 and NT-4 are elevated in the depressive phase of BD, 106 possibly indicating an attempt by the organism to defend itself against cellular stress. In turn, Barbosa et al 107 demonstrated decreased NT-3 and NT-4 levels in the manic phase of BD. Given that neurotrophins are essential for neuronal function and survival, it is assumed that the viability of nerve cells can be affected by a persistent reduction of these molecules in the nervous system.…”

Putative biological predictors of treatment response in bipolar disorders

“…Loch et al also reported increased plasma levels of both NT-3 and NT-4/5 in acutely depressed BD subjects compared to healthy controls; however, they did not find significant differences in NT-3 and NT-4/5 levels after lithium treatment [90]. Contrary to other reports, Barbosa et al reported decreased NT-4/5 plasma levels in BD patients with mania in comparison with controls without significant differences in NT-3 plasma levels between BD patients and controls [91].…”

Depression and Cardiovascular Disease: The Viewpoint of Platelets

“…NTs do not control directly mood but, they are fundamental in the activity-dependent modulation of networks and changes in plasticity [ 11 ]. Low NT levels have been associated with several affective disorders including bipolar depression (BD) [ 189 , 190 ], depression [ 12 , 191 ], mania [ 192 ], and obsessive compulsive disorders [ 193 ]. In particular, reductions in serum and plasma BDNF have been found in patients affected by depression [ 194 , 195 , 196 ], and in those who committed suicide [ 197 , 198 ].…”