Bioavailable testosterone is associated with symptoms of depression in adult men

Disturbed sex hormone milieu in males and females with major depressive disorder and low-grade inflammation

Sex hormones have biological effects on inflammation, and these might contribute to the sex-specific features of depression. C-reactive protein (CRP) is the most widely used inflammatory biomarker and consistent evidence shows a significant proportion (20-30 %) of patients with major depressive disorder (MDD) have CRP levels above 3 mg/L, a threshold indicating at least low-grade inflammation. Here, we investigate the interplay between sex hormones and CRP in the cross-sectional, observational Biomarkers in Depression Study. We measured serum high-sensitivity (hs-)CRP, in 64 healthy controls and 178 MDD patients, subdivided into those with hs-CRP below 3 mg/L (low-CRP; 53 males, 72 females) and with hs-CRP above 3 mg/L (high-CRP; 19 males, 34 females). We also measured interleukin-6, testosterone, 17-β-estradiol (E2), progesterone, sex-hormone binding globulin (SHBG), follicle-stimulating and luteinising hormones, and calculated testosterone-to-E2 ratio (T/E2), free androgen and estradiol indexes (FAI, FEI), and testosterone secretion index. In males, high-CRP patients had lower testosterone than controls (p = 0.001), and lower testosterone (p = 0.013), T/E2 (p < 0.001), and higher FEI (p = 0.015) than low-CRP patients. In females, high-CRP patients showed lower SHGB levels than controls (p = 0.033) and low-CRP patients (p = 0.034). The differences in testosterone, T/E2 ratio, and FEI levels in males survived the Benjamini-Hochberg FDR correction. In linear regression analyses, testosterone (β = -1.069 p = 0.033) predicted CRP concentrations (R2 = 0.252 p = 0.002) in male patients, and SHBG predicted CRP levels (β = -0.628 p = 0.009, R2 = 0.172 p = 0.003) in female patients. These findings may guide future research investigating interactions between gonadal and immune systems in depression, and the potential of hormonal therapies in MDD with inflammation.

Comprehensive Sex-Stratified Genetic Analysis of 28 Blood Biomarkers and Depression Reveals a Significant Association between Depression and Low Levels of Total Protein in Females

Introduction

Major depression (MD) is more common amongst women than men, and MD episodes have been associated with fluctuations in reproductive hormones amongst women. To investigate biological underpinnings of heterogeneity in MD, the associations between depression, stratified by sex and including perinatal depression (PND), and blood biomarkers, using UK Biobank (UKB) data, were evaluated, and extended to include the association of depression with biomarker polygenic scores (PGS), generated as proxy for each biomarker.

Method

Using female (N = 39,761) and male (N = 38,821) UKB participants, lifetime MD and PND were tested for association with 28 blood biomarkers. A GWAS was conducted for each biomarker and genetic correlations with depression subgroups were estimated. Using independent data from the Australian Genetics of Depression Study, PGS were constructed for each biomarker, and tested for association with depression status (n [female cases/controls] = 9,006/6,442; n [male cases/controls] = 3,106/6,222). Regions of significant local genetic correlation between depression subgroups and biomarkers highlighted by the PGS analysis were identified.

Results

Depression in females was significantly associated with levels of twelve biomarkers, including total protein (OR = 0.90, CI = [0.86, 0.94], p = 3.9 × 10-6) and vitamin D (OR = 0.94, CI = [0.90, 0.97], p = 2.6 × 10-4), and PND with five biomarker levels, also including total protein (OR = 0.88, CI = [0.81, 0.96], p = 4.7 × 10-3). Depression in males was significantly associated with levels of eleven biomarkers. In the independent Australian Genetics of Depression Study, PGS analysis found significant associations for female depression and PND with total protein (female depression: OR = 0.93, CI = [0.88, 0.98], p = 3.6 × 10-3; PND: OR = 0.91, CI = [0.86, 0.96], p = 1.1 × 10-3), as well as with vitamin D (female depression: OR = 0.93, CI = [0.89, 0.97], p = 2.0 × 10-3; PND: OR = 0.92, CI = [0.87, 0.97], p = 1.4 × 10-3). The male depression sample did not report any significant results, and the point estimate of total protein (OR = 0.98, CI = [0.92-1.04], p = 4.7 × 10-1) did not indicate any association. Local genetic correlation analysis highlighted significant genetic correlation between PND and total protein, located in 5q13.3 (rG = 0.68, CI = [0.33, 1.0], p = 3.6 × 10-4).

Discussion and Conclusion

Multiple lines of evidence from genetic analysis highlight an association between total serum protein levels and depression in females. Further research involving prospective measurement of total protein and depressive symptoms is warranted.

Role of sex hormone-binding globulin in the free hormone hypothesis and the relevance of free testosterone in androgen physiology

According to the free hormone hypothesis, biological activity of a certain hormone is best reflected by free rather than total hormone concentrations. A crucial element in this theory is the presence of binding proteins, which function as gatekeepers for steroid action. For testosterone, tissue exposure is governed by a delicate equilibrium between free and total testosterone which is determined through interaction with the binding proteins sex hormone-binding globulin and albumin. Ageing, genetics and various pathological conditions influence this equilibrium, hereby possibly modulating hormonal exposure to the target tissues. Despite ongoing controversy on the subject, strong evidence from recent in vitro, in vivo and human experiments emphasizes the relevance of free testosterone. Currently, however, clinical possibilities for free hormone diagnostics are limited. Direct immunoassays are inaccurate, while gold standard liquid chromatography with tandem mass spectrometry (LC-MS/MS) coupled equilibrium dialysis is not available for clinical routine. Calculation models for free testosterone, despite intrinsic limitations, provide a suitable alternative, of which the Vermeulen calculator is currently the preferred method. Calculated free testosterone is indeed associated with bone health, frailty and other clinical endpoints. Moreover, the added value of free testosterone in the clinical diagnosis of male hypogonadism is clearly evident. In suspected hypogonadal men in whom borderline low total testosterone and/or altered sex hormone-binding globulin levels are detected, the determination of free testosterone avoids under- and overdiagnosis, facilitating adequate prescription of hormonal replacement therapy. As such, free testosterone should be integrated as a standard biochemical parameter, on top of total testosterone, in the diagnostic workflow of male hypogonadism.

Baicalin Attenuates Continuous Activation of β-Catenin Induced by Lipopolysaccharide (LPS) and Depression Complicated by Infertility in Male Rats

Background

Baicalin (BA) is a potential candidate drug to inhibit depressive behavior. However, the mechanism of BA's role on depression complicated with male infertility (DCMI) is still unclear. This study aimed to investigate the role of BA in alleviating inflammatory factor-induced DCMI by regulating β-catenin.

Methods

Firstly, we performed sucrose preference test (SPT), open field test (OFT), tail suspension test (TST), and forced swim test (FST) in the chronic unpredictable mild stress (CUMS) + lipopolysaccharide (LPS) model rats to study the effect of BA on depressive behavior. The levels of neuropeptide Y (NPY), testosterone (T), and IL-1β, IL-6, TNF-α, IL-10, and IL-4 in the peripheral blood plasma of normal people, patients with depression, and patients with DCMI were measured. Then, the levels of IL-1β, IL-6, TNF-α, IL-10, IL-4, β-catenin in rat testis and peripheral blood and ANXA2, APP, SEMG1, and SEMG2 in seminal plasma proteins were examined. Moreover, the level of β-catenin in the testicular tissue was detected. LPS was used to treat Sertoli cells, and the level of β-catenin was detected. Finally, we evaluated the reproductive phenotype and sperm motility of rats.

Results

BA (especially 100 mg/kg) could notably ameliorate depression-like behavior induced by CUMS + LPS. The levels of IL-4, IL-10, T, and NPY in depression patients, DCMI patients, and CUMS + LPS model rats elevated, while the levels of IL-1β, IL-6, and TNF-α were reduced. However, BA alleviated the changes in these factors. Moreover, BA alleviated male rat depression induced by CUMS + LPS. LPS upregulated β-catenin (NP) but could not adjust β-catenin (TP) level in rat Sertoli cells. BA relieved the symptoms of DCMI by regulating β-catenin. Furthermore, BA ameliorated the reproductive ability of depressed rats.

Conclusion

BA modulated β-catenin in the relief of inflammatory factor-induced DCMI.

Association between Serum Testosterone Levels and Body Composition among Men 20-59 Years of Age

INTRODUCTION

Sex hormones play an important role in the development and maintenance of bone and muscle mass. However, studies regarding serum testosterone levels, osteoporosis, and sarcopenia in men are relatively sparse and have led to contradictory conclusions. Therefore, this study aimed to investigate the association between serum testosterone levels and body composition, including bone mineral density (BMD), appendicular lean mass index (ALMI), and appendicular fat mass index (AFMI), among men 20-59 years of age through a cross-sectional analysis of the National Health and Nutrition Examination Survey.

MATERIALS AND METHODS

Our analysis was based on the data for 3,875 men, 20-59 years of age. Weighted multiple regression analyses were used to estimate the independent association between serum testosterone levels and body composition. Weighted generalized additive models and smooth curve fittings were used to characterize the nonlinear associations between them.

RESULTS

The association between the serum testosterone level and lumbar BMD was positive in each multivariable linear regression model. In the model adjusted for age and race, the serum testosterone level was negatively associated with ALMI. However, in the models adjusted for body mass index, this association became positive. In addition, the association between the serum testosterone level and AFMI was negative in each multivariable linear regression model.

CONCLUSION

Our study demonstrated a positive association of serum testosterone level with lumbar BMD and ALMI, and a negative association with AFMI, among men 20-59 years of age, suggesting that increasing testosterone levels may be beneficial to skeletal health in young and middle-aged men with low testosterone levels.

The effects of methylated flavonoids on depression-like activity and pro-inflammatory cytokine thresholds in mice induced by repeated finasteride administration

The aim of the study was to investigate the influence of naringenin (NGN) and its methylated derivatives (50 or 100 mg kg−1) on finasteride-caused depression-like performance in mice to identify the effects on behavior and biomarkers of inflammation in the management of depression. Depression-like behavior was induced by repeated dose of finasteride (100 mg kg−1, subcutaneously) in mice. The effects of the naringenin (50 or 100 mg kg−1) or its methylated derivatives (Ngn-M; 50 or 100 mg kg−1 or Ngn-DM; 50 or 100 mg kg−1) and duloxetine (DXT, 10 mg kg−1) were evaluated for the immobility time in tail suspension and forced swimming tests following finasteride pre-treatment. The levels of brain pro-inflammatory cytokines such as IL-1β and TNF-α were also measured by Enzyme-Linked Immunosorbent Assay to further evaluate the impact of naringenin and its methylated derivatives on inflammation. Pre-treatment with finasteride substantially increased both the immobility time spent in tail suspension and forced swimming tests and brain levels of IL-1β and TNF–α in mice. Doluxetine (DLX) was given at a dose of 10 mg kg−1, and Naringenin or its methylated derivatives were given at doses of 50 and 100 mg kg−1 orally. It reduced immobility time in both tests, restored the preference to sucrose solution, and normalized cytokine levels (p < 0.01) in mice. Similar effects were observed with DTX (10 mg kg−1) as positive control. The increased brain levels of malondialdehyde (MDA) or nitrite were considerably (p < 0.05) decreased while substantially (p < 0.05) increased glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) levels after finasteride pre-treatment relative to vehicle-control by naringenin or its methylated derivatives (50 or 100 mg kg−1). These findings demonstrated the potential for methylated flavonoids as safe and effective anti-depressive agents.