OBJECTIVES: Neurotrophic factors exert substantial effects on the central nervous system. The present study investigates the roles of insulin-like growth factor-1 (IGF-1), β-nerve growth factor (β-NGF), and brain-derived neurotrophic factor (BDNF) in bipolar disorder. METHODS: Baseline levels of culture-stimulated IGF-1, β-NGF, and BDNF were compared in 116 patients with bipolar I disorder and 123 healthy controls. Neurotrophic factors were also compared in patients before and after 6 weeks of pharmacotherapy. A multivariate logistic regression analysis was used to investigate the influence of the neurotrophic factors analyzed in quartile form, in relation to confounding variables, such as age, sex, and body mass index. RESULTS: IGF-1 was significantly higher in patients (mean=514.57, SD=259.78) than in healthy controls (mean=316.82, SD=270.00, p<0.0001) at baseline. Furthermore, higher levels of IGF-1 substantially increased the risk for bipolar I disorder. IGF-1 level was not significantly changed at 6-weeks (mean=506.41, SD=313.66). No changes in BDNF or β-NGF-1 levels were found following the 6-week treatment period. IGF-1 and β-NGF were negatively correlated in healthy controls, but not in patients. Severity of manic symptoms was not associated with any of the neurotrophic factors. LIMITATIONS: We did not measure cortisol, growth hormone, or IGF-1 receptors. This study is cross-sectional in design. CONCLUSIONS: Elevated IGF-1 levels may be a trait marker for bipolar disorder. Further studies are needed to thoroughly investigate the role of IGF-1 in relation to other neuroendocrine factors and biological markers for bipolar disorder.
OBJECTIVES: Neurotrophic factors exert substantial effects on the central nervous system. The present study investigates the roles of insulin-like growth factor-1 (IGF-1), β-nerve growth factor (β-NGF), and brain-derived neurotrophic factor (BDNF) in bipolar disorder. METHODS: Baseline levels of culture-stimulated IGF-1, β-NGF, and BDNF were compared in 116 patients with bipolar I disorder and 123 healthy controls. Neurotrophic factors were also compared in patients before and after 6 weeks of pharmacotherapy. A multivariate logistic regression analysis was used to investigate the influence of the neurotrophic factors analyzed in quartile form, in relation to confounding variables, such as age, sex, and body mass index. RESULTS:IGF-1 was significantly higher in patients (mean=514.57, SD=259.78) than in healthy controls (mean=316.82, SD=270.00, p<0.0001) at baseline. Furthermore, higher levels of IGF-1 substantially increased the risk for bipolar I disorder. IGF-1 level was not significantly changed at 6-weeks (mean=506.41, SD=313.66). No changes in BDNF or β-NGF-1 levels were found following the 6-week treatment period. IGF-1 and β-NGF were negatively correlated in healthy controls, but not in patients. Severity of manic symptoms was not associated with any of the neurotrophic factors. LIMITATIONS: We did not measure cortisol, growth hormone, or IGF-1 receptors. This study is cross-sectional in design. CONCLUSIONS: Elevated IGF-1 levels may be a trait marker for bipolar disorder. Further studies are needed to thoroughly investigate the role of IGF-1 in relation to other neuroendocrine factors and biological markers for bipolar disorder.
Authors: Elena Milanesi; Adva Hadar; Elisabetta Maffioletti; Haim Werner; Noam Shomron; Massimo Gennarelli; Thomas G Schulze; Marta Costa; Maria Del Zompo; Alessio Squassina; David Gurwitz Journal: J Mol Neurosci Date: 2015-03-05 Impact factor: 3.444
Authors: Brisa S Fernandes; Marc L Molendijk; Cristiano A Köhler; Jair C Soares; Cláudio Manuel G S Leite; Rodrigo Machado-Vieira; Thamara L Ribeiro; Jéssica C Silva; Paulo M G Sales; João Quevedo; Viola Oertel-Knöchel; Eduard Vieta; Ana González-Pinto; Michael Berk; André F Carvalho Journal: BMC Med Date: 2015-11-30 Impact factor: 8.775
Authors: Victor Munive; Jonathan A Zegarra-Valdivia; Raquel Herrero-Labrador; Ana M Fernandez; Ignacio Torres Aleman Journal: Aging (Albany NY) Date: 2019-01-11 Impact factor: 5.682