Peripheral insulin-like growth factor 1 in bipolar disorder

• Published in: Psychiatry research Vol. 250; pp. 30 - 34
• Main Authors: da Silva, Emily G., Pfaffenseller, Bianca, Walz, Julio, Stertz, Laura, Fries, Gabriel, Rosa, Adriane R., Magalhães, Pedro V.
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01.04.2017
• Subjects: Adult; Bipolar disorder; Bipolar Disorder - blood; Female; Human Growth Hormone - blood; Humans; IGF-1; Inflammation; Insulin - blood; Insulin-Like Growth Factor I - metabolism; Male; Middle Aged; Neurotrophins; Psychiatry; Reference Values; Tumor Necrosis Factor-alpha - blood; Bipolar disorder; IGF-1; Inflammation; Neurotrophins
• ISSN: 0165-1781; 1872-7123; 1872-7123
• DOI: 10.1016/j.psychres.2017.01.061

Bipolar disorder is a recurrent and highly incapacitating illness, related to inflammation and changes in the insulin-like growth factor 1 (IGF-1). The objective of this study was to evaluate serum levels of IGF-1 in bipolar disorder patients and its relation to inflammation. We included 31 patients with bipolar disorder and 33 healthy controls. Serum concentrations of IGF-1, growth hormone (GH), insulin and tumor necrosis factor α (TNF-α) were analyzed. The serum levels of IGF-1 seem to be increased in bipolar disorder patients (248.84±104.91ng/mL) compared to controls (169.18±74.16ng/mL). Comparing reference values of IGF serum concentrations between groups, we found that 32% of patients had increased IGF-1 serum concentrations while only 3% of subjects are above normal range. We did not find statistically significant differences between groups in the concentration of insulin, GH, and TNF-α. This study suggests an association between IGF-1 in the pathophysiology of bipolar disorder. It is possible that this peripheral increase is related to a central nervous system increased resistance to IGF-1, thus reducing its neuroprotective action. •We evaluated IGF-1 serum levels in bipolar disorder euthymic patients.•There was a significant increase in IGF-1 serum levels in bipolar disorder patients.•There is evidence of IGF-1 role in specific brain regions, such as hippocampus, which is also impared in the bipolar disorder.