Associations between Sex Hormones and Circulating Growth Differentiation Factor-15 in Male Patients with Major Depressive Disorder

Ting Sun,Yan Li,Xiaojun Sun,Rui Peng

doi:10.3390/brainsci11121612

Abstract

The interaction between the endocrine system and inflammation is crucial pathogenesis of depression. Our study aimed at exploring the possible relationship between sex hormones and growth differentiation factor-15 (GDF-15), a common indicator of inflammation in male patients with major depressive disorder (MDD). Methods: GDF-15 levels of 121 male MDD patients were compared with 105 healthy subjects with the help of a Cobas 8000 automatic chemiluminescence immunoanalyzer. Results: (1) MDD patients showed higher GDF-15 levels, a lower testosterone (T) level and testosterone/estradiol ratio (T/E2 ratio) than healthy subjects (all p < 0.05). (2) Serum T levels and the T/E2 ratio were inversely associated with GDF-15 serum levels (all p < 0.05). (3) HAMD-24 scores were positively correlated with the levels of GDF-15 (p < 0.01), but not with T levels, estradiol (E2) levels, and the T/E2 ratio (all p > 0.05). Conclusion: The high level of GDF-15 was correlated with a low T/E2 ratio and T deficiency in male MDD patients. The above results demonstrate that up-regulation of serum GDF-15 and down-regulation of T and T/E2 ratio may be correlated with the occurrence and severity of depression. So, changing the level of GDF-15 by regulating the proportion of sex hormones may play a key role in the prognosis and treatment of depression.

Highlights

Major depressive disorder (MDD) is a serious and complex psychiatric disorder with a high rate of disability, morbidity, and recurrence, which may seriously damage social and cognitive functions [1,2,3]
Our group previously demonstrated that an unbalanced T/E2 ratio is closely related to the etiology and pathogenesis of MDD and that a combined T and E2 supplementation is more effective than T or E2 alone [8]
Levels of inflammatory indexes such as high-sensitivity C-reactive protein (hs-CRP) and White blood cell (WBC) were higher in male MDD patients than in healthy subjects

Summary

Introduction

Major depressive disorder (MDD) is a serious and complex psychiatric disorder with a high rate of disability, morbidity, and recurrence, which may seriously damage social and cognitive functions [1,2,3]. One limitation found in the previous work on the relationship between sex hormone levels and depression is that it assessed the estradiol (E2) and T effects independently; the potential interactions or synergistic effects between the two were overlooked. Another weakness is that most previous studies failed to adjust for confounding factors that may affect T levels and depressive symptoms. Our group previously demonstrated that an unbalanced T/E2 ratio is closely related to the etiology and pathogenesis of MDD (which is mediated by the inflammatory response) and that a combined T and E2 supplementation is more effective than T or E2 alone [8]

Methods

Results

Conclusion