Sex hormone-binding globulin: biomarker and hepatokine?

Associations between exposure to phthalates and liver function among women undergoing assisted reproductive technology

Phthalates can induce hepatotoxicity in animal studies. We aimed to assess the associations of individual and mixture of urinary phthalate metabolites with serum liver function indicators among 764 women undergoing assisted reproductive technology (ART). In linear models, we observed inverse correlations between urinary mono-benzyl phthalate and serum total protein (TP) as well as globulin (β=-0.27 and -0.23, respectively, P<0.05). Additionally, negative associations were identified between mono-isobutyl phthalate and mono-butyl phthalate (MBP) and aspartate aminotransferase-to-alanine transaminase ratio (AST/ALT) (P<0.05). MBP and the sum of all phthalate metabolites (∑all.phth.m) were positively associated with bilirubin, with β ranging from 0.14 to 0.47. Most phthalate metabolites were also positively related to gamma-glutamyl transferase (GGT) (all P<0.05). In Bayesian kernel machine regression models, phthalate mixture was positively associated with bilirubin and GGT, whereas inversely associated with AST/ALT and TP. Our results suggest that phthalate exposure may impair liver function among women undergoing ART.

Association of sex hormones with non-alcoholic fatty liver disease: An observational and Mendelian randomization study

BACKGROUND AND AIMS

Sex-specific associations of sex hormone-binding globulin (SHBG) and bioavailable testosterone (BAT) with NAFLD remain indeterminate. We aimed to explore observational and genetically determined relationships between each hormone and NAFLD.

METHODS

We included 187 395 men and 170 193 women from the UK Biobank. Linear and nonlinear Cox regression models and Mendelian randomization (MR) analysis were used to test the associations.

RESULTS

During 12.49 years of follow-up, 2209 male and 1886 female NAFLD cases were documented. Elevated SHBG levels were linearly associated with a lower risk of NAFLD in women (HR (95% CI), .71 (.63, .79)), but not in men (a "U" shape, pnon-linear < .001). Higher BAT levels were associated with a lower NAFLD risk in men (HR (95% CI), .81 (.71, .93)) but a higher risk in women (HR (95% CI): 1.25 (1.15, 1.36)). Genetically determined SHBG and BAT levels were linearly associated with NAFLD risk in women (OR (95% CI): .57 (.38, .87) and 2.21 (1.41, 3.26) respectively); in men, an "L-shaped" MR association between SHBG levels and NAFLD risk was found (pnon-linear = .016). The bidirectional MR analysis further revealed the effect of NAFLD on SHBG and BAT levels in both sexes.

CONCLUSIONS

Consistently, linear associations of lower SHBG and higher BAT levels with increased NAFLD risk were both conventionally and genetically found in women, while in men, SHBG acts in a nonlinear manner. In addition, NAFLD may affect SHBG and BAT levels.

Creating machine learning models that interpretably link systemic inflammatory index, sex steroid hormones, and dietary antioxidants to identify gout using the SHAP (SHapley Additive exPlanations) method

Background

The relationship between systemic inflammatory index (SII), sex steroid hormones, dietary antioxidants (DA), and gout has not been determined. We aim to develop a reliable and interpretable machine learning (ML) model that links SII, sex steroid hormones, and DA to gout identification.

Methods

The dataset we used to study the relationship between SII, sex steroid hormones, DA, and gout was from the National Health and Nutrition Examination Survey (NHANES). Six ML models were developed to identify gout by SII, sex steroid hormones, and DA. The seven performance discriminative features of each model were summarized, and the eXtreme Gradient Boosting (XGBoost) model with the best overall performance was selected to identify gout. We used the SHapley Additive exPlanation (SHAP) method to explain the XGBoost model and its decision-making process.

Results

An initial survey of 20,146 participants resulted in 8,550 being included in the study. Selecting the best performing XGBoost model associated with SII, sex steroid hormones, and DA to identify gout (male: AUC: 0.795, 95% CI: 0.746- 0.843, accuracy: 98.7%; female: AUC: 0.822, 95% CI: 0.754- 0.883, accuracy: 99.2%). In the male group, The SHAP values showed that the lower feature values of lutein + zeaxanthin (LZ), vitamin C (VitC), lycopene, zinc, total testosterone (TT), vitamin E (VitE), and vitamin A (VitA), the greater the positive effect on the model output. In the female group, SHAP values showed that lower feature values of E2, zinc, lycopene, LZ, TT, and selenium had a greater positive effect on model output.

Conclusion

The interpretable XGBoost model demonstrated accuracy, efficiency, and robustness in identifying associations between SII, sex steroid hormones, DA, and gout in participants. Decreased TT in males and decreased E2 in females may be associated with gout, and increased DA intake and decreased SII may reduce the potential risk of gout.

Association of Androgen Hormones, Sex Hormone-Binding Globulin, and the Menopausal Transition With Incident Diabetes Mellitus in Women With and Without HIV

BACKGROUND

HIV is associated with alterations in androgen hormone levels and sex hormone-binding globulin (SHBG) in women. Higher SHBG has been associated with a lower risk of diabetes in the general population, but the contribution of HIV, androgen hormones, SHBG, and menopausal phase to diabetes is unclear.

METHODS

From April 2003 through February 2020, 896 women with HIV (WWH) and 343 women without HIV (WWOH) from the Women's Interagency HIV Study with morning total testosterone, dehydroepiandrosterone sulfate (DHEAS), and SHBG levels were followed to assess for incident diabetes. Parametric regression models were used with age as the time scale and relative times (RT) as the measure of association of hormone level and menopausal phase with incident diabetes. Analyses incorporated time-dependent androgen hormone, SHBG levels, and menopausal phase and were adjusted for race/ethnicity, enrollment year, smoking status, BMI, hepatitis C virus status, and HIV-related factors.

RESULTS

In total, 128 (14%) WWH and 47 (14%) WWOH developed diabetes. In WWH, a doubling of SHBG and DHEAS were associated with a 7% (RT = 1.07 [95% CI: 0.82 to 1.40] and 15% (RT = 1.15 [95% CI: 0.95 to 1.39]) longer time to diabetes, respectively; in WWOH, a doubling of SHBG and DHEAS were associated with 84% (RT = 1.84 [95% CI: 0.89 to 3.82]) and 41% (RT= 1.41 [95% CI: 0.82 to 2.44]) longer times to diabetes. Total testosterone was not associated. In WWH, later menopausal phase was associated with shorter times to diabetes.

CONCLUSIONS

Despite alterations in androgen hormone and SHBG levels in HIV, regardless of HIV status, higher SHBG and DHEAS were associated with nonstatistically significant slower progression to diabetes. The menopausal transition may be a better hormonal indicator of diabetes risk in WWH.

A protective role of genetically predicted sex hormone-binding globulin on stroke

Introduction

The role of sex hormone-binding globulin (SHBG) on stroke has been investigated in several observational studies. To provide the causal estimates of SHBG on stroke and its subtypes, bi-directional and multivariable Mendelian randomization (MR) analyses are performed.

Methods

The genetic instruments of SHBG were obtained from the UK Biobank. Outcome datasets for stroke and its subtypes were taken from the MEGASTROKE Consortium. The main analysis used in this study is the inverse variance weighting, complemented by other sensitivity approaches to verify the conformity of findings.

Results

We found that the risk of stroke grew by 13% (odd ratio [OR] = 0.87, 95% confidence interval [CI] = 0.79-0.95, P = 0.0041) and the risk of ischemic stroke grew by 15% (OR = 0.85, 95%CI = 0.77-0.95, P = 0.0038) caused by genetically predicted SHBG. The causal association remains robust in the reverse MR and multivariable MR analyses for stroke (reverse MR: all P > 0.01 for the IVW method; MVMR: OR = 0.72, 95%CI = 0.59-0.87, P = 0.0011) and ischemic stroke (reverse MR: all P > 0.01 for IVW; MVMR: OR = 0.70, 95%CI = 0.56-0.86, P = 0.0007).

Conclusion

Our MR study provides novel evidence that SHBG has an inverse association with stroke and ischemic stroke, exerting protective effects on stroke.

The Association Between SHBG and Osteoporosis: A NHANES Cross-Sectional Study and A Bidirectional Mendelian Randomization

This study aimed to examine the association between sex hormone-binding globulin (SHBG) and osteoporosis through a cross-sectional study and a two-sample bidirectional Mendelian randomization (MR). We used the National Health and Nutrition Examination Survey (NHANES) 2013-2014 and 2015-2016 data, with exposure as serum SHBG and outcome as osteoporosis and performed multivariate logistic regression to test the correlation between SHBG and osteoporosis. To determine the causal relationship between SHBG and osteoporosis, a two-sample bidirectional MR was employed. The genome-wide association study (GWAS) dataset for SHBG (n = 189,473) was obtained from the IEU database, and the GWAS dataset for osteoporosis (n = 212,778) was obtained from the FinnGen bioBank. The principal MR technique was inverse-variance weighting (IVW). In MR analyses, the MR-Egger intercept and Cochran Q test were used to detect multiple validity and horizontal heterogeneity. 1249 older adult participants (age ≥ 60) were involved in the cross-sectional study, including 113 osteoporosis cases. We identified a significant relationship between circulating SHBG concentration and osteoporosis risk [OR 3.963, 95% CI (2.095-7.495), P < 0.05]. Subgroup analysis indicated that SHBG was closely linked to the risk of osteoporosis in the female population [OR 1.008, 95% CI (1.002-1.013), P = 0.005] but not in males (P = 0.065). In addition, The IVW approach suggested a causal connection between SHBG and increased osteoporosis risk [OR 1.479, 95% CI (1.144-1.912), P = 0.003], and the MR-Egger intercept and the Cochran Q test validated the consistency of the MR results. Finally, the reverse MR analysis declined to identify a causal relation between SHBG and osteoporosis. Our research demonstrates a significant causal connection between circulating SHBG levels and increased osteoporosis risk. These results indicate that high SHBG may be associated with the risk of osteoporosis in postmenopausal women, but more research is needed.

Low levels of sex hormone-binding globulin predict an increased breast cancer risk and its underlying molecular mechanisms

Sex hormone-binding globulin (SHBG) is a serum glycoprotein exhibiting the unique feature of binding sex steroids with high affinity and specificity. Over the past few decades, there have been significant breakthroughs in our understanding of the function and regulation of SHBG. The biological role of SHBG has expanded from being considered a simple sex hormone transporter to being associated with several complex physiological and pathological changes in a variety of target tissues. Many factors can affect the plasma SHBG levels, with fluctuations in circulating levels affecting the development of various diseases, such as increasing the risk of developing breast cancer. This article reviews the clinical significance of changes in circulating SHBG levels in the development of breast cancer and the possible influence of these levels on endocrine drug resistance in hormone receptor-positive breast cancer. Higher levels of plasma SHBG significantly reduce the risk of estrogen receptor-positive breast cancer, especially in postmenopausal women. Moreover, the molecular mechanisms by which SHBG affects breast cancer risk are also summarized in detail. Finally, transcriptomics and proteomics data revealed that SHBG expression in breast tissue can effectively distinguish breast cancer from normal tissue. Additionally, the association between SHBG expression levels and various classical tumor-related pathways was investigated.

Associations of Serum Testosterone and Sex Hormone-binding Globulin With Incident Arrhythmias in Men From UK Biobank

CONTEXT

Sex hormones have been identified as cardiovascular risk factors, whereas the relationship between sex hormones and the risk of arrhythmias in men has not yet been well studied in the prospective cohort study.

OBJECTIVE

To analyze associations of serum testosterone and SHBG concentrations and calculate free testosterone (cFT) with arrhythmias in men.

METHODS

Sex hormones were measured at baseline from UK Biobank. Main outcomes were incidence of atrial fibrillation/flutter (AF), ventricular arrhythmia (VA), and bradyarrhythmia (BA).

RESULTS

Of 173 498 men (aged 37-73 years, followed for 11 years), 11 368 had incident AF, 1646 had incident VA, and 4788 had incident BA. Compared with the third quartiles, the lowest category of serum testosterone was associated with increased risks of AF (hazard ratio [HR], 1.06; 95% CI, 1.00-1.12) and BA (HR, 1.11; 95% CI, 1.02-1.20) after multivariable adjustment, but no VA. Likewise, similar associations were found between cFT values and AF and BA events. Furthermore, higher levels of cFT were associated with increased risks of AF (HR, 1.07; 95% CI, 1.02-1.13) and VA (HR, 1.18; 95% CI, 1.01-1.37). Higher SHBG concentrations were associated with increased risks of AF (HR, 1.44; 95% CI, 1.34-1.54), VA (HR, 1.27; 95% CI, 1.07-1.52), and BA (HR, 1.17; 95% CI ,1.05-1.29).

CONCLUSIONS

Lower levels of testosterone and cFT were associated with increased risk of AF and BA. Higher cFT levels were associated with increased risk of AF and VA. Higher SHBG levels were associated with increased risk of AF, VA, and BA.

Fructose intake from sugar-sweetened beverages is associated with a greater risk of hyperandrogenism in women: UK Biobank cohort study

OBJECTIVE

To assess the association between fructose consumption and serum sex hormone-binding globulin (SHBG), (free) testosterone, and risk of hyperandrogenism in a population-based cohort.

DESIGN

An observational and genetic association study in participants of the UK Biobank (n = 136 384 and n = 383 392, respectively).

METHODS

We assessed the relationship of (1) the intake of different sources of fructose (ie, total, fruit, fruit juice, and sugar-sweetened beverages [SSBs]) and (2) rs2304681 (a missense variant in the gene encoding ketohexokinase, used as an instrument of impaired fructose metabolism), with SHBG, total and free testosterone levels, and risk of hyperandrogenism (free androgen index >4.5).

RESULTS

The intake of total fructose and fructose from fruit was associated with higher serum SHBG and lower free testosterone in men and women and lower risk of hyperandrogenism in women. In contrast, fructose intake from SSB (≥10 g/day) was associated with lower SHBG in men and women and with higher free testosterone levels and risk of hyperandrogenism in women (odds ratio [OR]: 1.018; 95% confidence interval [CI]: 1.010; 1.026). Carriers of the rs2304681 A allele were characterized by higher circulating SHBG (both men and women), lower serum free testosterone (women), and a lower risk of biochemical hyperandrogenism (OR: 0.997, 95% CI: 0.955; 0.999; women) and acne vulgaris (OR: 0.975, 95% CI: 0.952; 0.999; men and women combined).

CONCLUSIONS

The consumption of ≥10 g/day fructose from SSB, corresponding to ≥200 mL serving, is associated with a 2% higher risk of hyperandrogenism in women. These observational data are supported by our genetic data.

The relationship between sex hormone-binding protein and non-alcoholic fatty liver disease using Mendelian randomisation

BACKGROUND

The incidence of non-alcohol fatty liver disease (NAFLD) has been increasing annually with the improvement of living standards. Numerous epidemiological observations have linked sex hormone-binding protein (SHBG) levels to NAFLD. However, evidence of the causal role of SHBG in the development and progression of NAFLD is still absent. Therefore, a systematic assessment of the causal relationship is needed.

METHOD

A two-sample Mendelian randomisation (MR) analysis was conducted. Genome-wide association study (GWAS) data for SHBG were obtained online from the IEU database (ebi-a-GCST90012111) as exposure. GWAS data from the NAFLD of the Finngen consortium were used for preliminary analysis, while NAFLD data from another GWAS involving 8434 participants were used for replication and meta-analyses. Causal effects were investigated with inverse variance weighted (IVW), weighted median and MR-Egger regression. Sensitivity analyses including Cochran's Q test, leave-one-out analysis and MR-Egger intercept analysis were simultaneously conducted to assess heterogeneity and pleiotropy.

RESULTS

After rigorous selection, 179 single-nucleotide polymorphisms (SNPs) were identified as strongly correlated instrumental variables. Preliminary analysis suggested a significant causal relationship between genetically determined serum SHBG levels and NAFLD [odds ratio (OR) IVW  = .54, 95% confidence interval (CI) = .30-.98, p = .043], supported by the results of the replication analysis (ORIVW  = .61, 95% CI = .46-.81, p = .0006) and further meta-analysis (OR = .59, 95% CI = .46-.77, p < .0001).

CONCLUSION

The genetic tendency to high levels of SHBG was causally correlated with a reduced risk of NAFLD, indicating that circulating high levels of SHBG was a protective factor for NAFLD.

Inter-organ crosstalk during development and progression of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is characterized by tissue-specific insulin resistance and pancreatic β-cell dysfunction, which result from the interplay of local abnormalities within different tissues and systemic dysregulation of tissue crosstalk. The main local mechanisms comprise metabolic (lipid) signalling, altered mitochondrial metabolism with oxidative stress, endoplasmic reticulum stress and local inflammation. While the role of endocrine dysregulation in T2DM pathogenesis is well established, other forms of inter-organ crosstalk deserve closer investigation to better understand the multifactorial transition from normoglycaemia to hyperglycaemia. This narrative Review addresses the impact of certain tissue-specific messenger systems, such as metabolites, peptides and proteins and microRNAs, their secretion patterns and possible alternative transport mechanisms, such as extracellular vesicles (exosomes). The focus is on the effects of these messengers on distant organs during the development of T2DM and progression to its complications. Starting from the adipose tissue as a major organ relevant to T2DM pathophysiology, the discussion is expanded to other key tissues, such as skeletal muscle, liver, the endocrine pancreas and the intestine. Subsequently, this Review also sheds light on the potential of multimarker panels derived from these biomarkers and related multi-omics for the prediction of risk and progression of T2DM, novel diabetes mellitus subtypes and/or endotypes and T2DM-related complications.

No evidence of genetic causal association between sex hormone-related traits and systemic lupus erythematosus: A two-sample Mendelian randomization study

OBJECTIVE

Previous studies have demonstrated an association between sex hormone-related traits and systemic lupus erythematosus (SLE). However, because of the difficulties in determining sequential temporality, the causal association remains elusive. In this study, we used two-sample Mendelian randomization (MR) to explore the genetic causal associations between sex hormone-related traits and SLE.

METHODS

We used a two-sample MR to explore the causal association between sex hormone-related traits and SLE. The summarized data for sex hormone-related traits (including testosterone, estradiol (E2), sex hormone-binding globulin (SHBG), and bioavailable testosterone (BT)) originated from large genome-wide association studies (GWASs) of European descent. Aggregated data for SLE were derived from the FinnGen consortium (835 cases and 300,162 controls). Random-effects inverse-variance weighted (IVW), MR-Egger, weighted median, simple mode, weighted mode, and fixed-effects IVW methods were used for the MR analysis. Random-effects IVW was the primary method used to analyze the genetic causal association between sex hormone-related traits and SLE. Heterogeneity of the MR results was detected using the IVW Cochran's Q estimates. The pleiotropy of MR results was detected using MR-Egger regression and the MR pleiotropy residual sum and outlier (MR-PRESSO) test. Finally, leave-one-out analysis was performed to determine whether MR results were affected by a single single-nucleotide polymorphism (SNP).

RESULTS

Random-effects IVW as the primary method showed that testosterone (odds ratio (OR), 0.87; 95% confidence interval (CI), 0.41-1.82; P = 0.705), E2 (OR, 0.95; 95% CI, 0.73-1.23; P = 0.693), SHBG (OR, 1.25; 95% CI, 0.74-2.13; P = 0.400), and BT (OR, 0.99; 95% CI, 0.67-1.47; P = 0.959) had no potential causal association with SLE. The MR-Egger, weighted median, simple mode, weighted mode, and fixed-effects IVW methods all indicated consistent results. The results of the MR-Egger regression showed that there was no pleiotropy in our MR analysis (P > 0.05). The IVW Cochran's Q estimates showed that the MR analysis results of E2, SHBG, and BT on SLE had no heterogeneity (P > 0.05), but testosterone and SLE had heterogeneity (P < 0.05). The leave-one-out analysis confirmed that a single SNP did not affect the MR results.

CONCLUSIONS

Our MR analysis demonstrated that genetically predicted testosterone, E2, SHBG, and BT levels were not associated with SLE risk, but the roles of other non-genetic pathways cannot be ruled out. Key Points • This is the first MR study to explore the causal association of sex hormone-related traits with SLE. • No evidence to support causal associations between sex hormone-related traits and SLE. • Our MR analysis may provide novel insights into the causal association between sex hormone-related traits and SLE risk.

Is elevated baseline SHBG associated with increased ovulation?

Sexual hormone binding globulin (SHBG) is associated with the endocrine and reproductive systems. We aimed to investigate the role of SHBG in the reproductive process. Therefore, we conducted a secondary analysis of the PCOSAct (Polycystic Ovary Syndrome and Acupuncture Clinical Trial) study, which involved 21 sites in China and a total of 1000 women with PCOS. Out of these, 954 women with SHBG were included in the analysis. Through multivariate analysis of ovulation predictors, we found that age, BMI, estradiol, testosterone, and SHBG all showed a positive predictive value for ovulation (p = 0.0211, 0.0011, 0.0211, 0.0029, 0.0434, respectively). However, the LH to FSH ratio had a negative predictive value (p = 0.0539). Higher quartiles of SHBG were associated with a higher rate of ovulation, and per quartile increased was statistically significant (HR = 1.138, 95%CI [1.054,1.229]). The association remained significant even after adjusting for testosterone (HR = 1.263, 95%CI [1.059, 1.507]). On the other hand, quartiles of testosterone and estradiol did not exhibit any significant tendency toward ovulation. SHBG demonstrated predictive ability for ovulation, conception, pregnancy, and live birth (p < 0.05), and this correlation remained significant after adjusting intervention. Kaplan-Meier curves illustrated that increased levels of SHBG were a factor in high rates of ovulation, conception, and pregnancy. In comparison to other sexual hormones, a higher baseline level of SHBG was related to increased ovulation.

Causal inference of sex hormone-binding globulin on venous thromboembolism: evidence from Mendelian randomisation

BACKGROUND

Previous cohort studies have shown that exogenous sex hormone use, such as testosterone replacement therapy and oestrogen-containing contraceptives, can increase the risk of venous thromboembolism (VTE). However, the relationship between endogenous sex hormone levels and VTE remains unclear. The goal of the present study was to explore the causal roles of endogenous sex hormones, including hormone-binding globulin (SHBG), bioactive testosterone (BT), and total testosterone (TT), in VTE and its two subgroups, deep vein thrombosis (DVT) and pulmonary embolism (PE).

METHODS

We used a genome-wide association study of sex hormones as exposure data and Finnish VTE data as the outcome. Inverse variance weighting, MR-Egger, and weighted median were used for two-sample Mendelian randomisation (MR). Sensitivity analyses included MR-Egger, MR-PRESSO, Cochrane Q test, MR Steiger, leave-one-out analysis, and funnel plot, combined with multivariate MR and replicated MR analyses using larger VTE data from the global biobank meta-analysis initiative. Linkage disequilibrium score regression (LDSC) was used to determine genetic associations and estimate sample overlap.

RESULTS

Our findings genetically predicted that an increase in serum SHBG levels by one standard deviation (SD) caused 25% higher odds for VTE (OR: 1.25, 95% CI: 1.01-1.55) and 58% higher odds for PE (OR: 1.58, 95% CI: 1.20-2.08). LDSC supported the genetic correlation between these two traits and replicated analyses confirm SHBG's genetic effect on VTE in both sexes (OR: 1.46, 95% CI: 1.20-1.78) and in females (OR: 1.49, 95% CI: 1.17-1.91). In addition, an increase in serum TT levels by one SD caused 32% higher odds for VTE (OR: 1.32, 95% CI: 1.08-1.62) and 31% higher odds for DVT (OR: 1.31, 95% CI: 1.01-1.69); however, LDSC and replicated analyses did not find a genetic correlation between TT and VTE or its subtypes. No significant correlation was observed between BT and all three outcome traits.

CONCLUSION

Our study provides evidence that elevated serum SHBG levels, as predicted by genetics, increase VTE risk. However, the causal effect of testosterone levels on VTE requires further investigation.

Hepatokine Profile in Adolescents with Polycystic Ovary Syndrome: A Case-Control Study

The current guidelines suggest routine screening for non-alcoholic fatty liver disease (NAFLD) in patients with polycystic ovary syndrome (PCOS). Hepatokines seem to be promising surrogate endpoints for the diagnosis and severity of NAFLD. PCOS has its onset in adolescence and its metabolic sequalae begin during the same period. There are scarce data on the hepatokine profile of adolescent PCOS patients. This case-control study examined the serum profile of the hepatokines sex hormone-binding globulin (SHBG), selenoprotein P, fibroblast growth factor 21 (FGF21), and fetuin A in a sample of adolescent PCOS patients, and their association to metabolic and hormonal parameters. The selenoprotein P and SHBG serum concentrations were significantly decreased in PCOS patients vs. the controls (median (IQR), 2.47 (0.40) vs. 2.66 (0.36) μg/mL, p = 0.025; mean ± SD, 41.71 ± 19.41 vs. 54.94 ± 22.12 nmol/L, p = 0.011, respectively), whereas selenoprotein P was significantly and positively associated with testosterone (r = 0.325, p = 0.007) and the free androgen index (r = 0.361, p = 0.002). The SHBG demonstrated multiple significant negative correlations with adverse metabolic parameters. Among the PCOS patients, the FGF21 concentrations were significantly higher in those with NAFLD, whereas a 1 pg/mL increase in the FGF21 concentration increased the odds of NAFLD diagnosis by liver ultrasound by 1%, suggesting FGF21 as a potential biomarker for hepatic disease in females with PCOS in adolescence. Fetuin A was the least differentiated hepatokine between the PCOS patients and controls with the least associations with metabolic and hormonal parameters.

Sex Hormone-Binding Globulin and Risk of Coronary Heart Disease in Men and Women

BACKGROUND

The role of sex hormone-binding globulin (SHBG) levels in clinical risk stratification and intervention for coronary heart disease (CHD) remains uncertain. We aimed to examine whether circulating levels of SHBG are predictive of CHD risk in men and women.

METHODS

We investigated the association between SHBG and the risk of incident CHD in 128 322 men and 135 103 women free of CHD at baseline in the prospective United Kingdom Biobank (UKB) cohort. The unconfounded associations were estimated using Mendelian randomization (MR) analysis. We further conducted a meta-analysis to integrate currently available prospective evidence. CHD events included nonfatal and fatal myocardial infarction and coronary revascularization.

RESULTS

In the UKB, during a median of 11.7 follow-up years, 10 405 men and 4512 women developed CHD. Serum levels of SHBG were monotonically associated with a decreased risk of CHD in both men (adjusted hazard ratio [HR] per log nmol/L increase in SHBG: 0.88 [0.83-0.94]) and women (HR: 0.89 [0.83-0.96]). MR-based analyses suggested causality and a dose-response relationship of SHBG with CHD risk. A cumulative meta-analysis including 216 417 men and 138 282 women from 11 studies showed that higher levels of SHBG were prospectively associated with decreased CHD risk in men comparing the highest with the lowest quartile: pooled relative risk (RR) 0.81 (0.74-0.89) and women (pooled RR: 0.86 [0.78-0.94]).

CONCLUSIONS

Higher circulating SHBG levels were directly and independently predictive of lower CHD risk in both men and women. The utility of SHBG for CHD risk stratification and prediction warrants further study.

The role of Th17 cells in endocrine organs: Involvement of the gut, adipose tissue, liver and bone

T Helper 17 (Th17) cells are adaptive immune cells that play myriad roles in the body. Immune-endocrine interactions are vital in endocrine organs during pathological states. Th17 cells are known to take part in multiple autoimmune diseases over the years. Current evidence has moved from minimal to substantial that Th17 cells are closely related to endocrine organs. Diverse tissue Th17 cells have been discovered within endocrine organs, including gut, adipose tissue, liver and bone, and these cells are modulated by various secretions from endocrine organs. Th17 cells in these endocrine organs are key players in the process of an array of metabolic disorders and inflammatory conditions, including obesity, insulin resistance, nonalcoholic fatty liver disease (NAFLD), primary sclerosing cholangitis (PSC), osteoporosis and inflammatory bowel disease (IBD). We reviewed the pathogenetic or protective functions played by Th17 cells in various endocrine tissues and identified potential regulators for plasticity of it. Furthermore, we discussed the roles of Th17 cells in crosstalk of gut-organs axis.

Association between acrylamide exposure and sex hormones among premenopausal and postmenopausal women: NHANES, 2013-2016

PURPOSE

Acrylamide (AA) is a potential carcinogen that mainly comes from fried, baked and roasted foods, and Hb adducts of AA (HbAA) and its metabolite glycidamide (HbGA) are the biomarkers of its exposure. Increasing evidence suggests that AA is associated with various hormone-related cancers. This study aims to explore the association of HbAA and HbGA with female serum sex hormone concentrations.

METHODS

942 women from the National Health and Nutrition Examination Survey cycles (2013-2016) were included in this cross-sectional study. The associations between HbAA or HbGA or HbGA/HbAA and sex hormones were assessed by the multiple linear regression. Further stratified analyses were conducted to figure out the effects of menopausal status, BMI and smoking status on sex hormone levels.

RESULTS

Among all participants, 597 were premenopausal and 345 were postmenopausal. HbAA was positively associated with both two androgen indicators. Specifically, a ln-unit increase in HbAA was associated with 0.41 ng/dL higher ln(total testosterone, TT) (95% CI 0.00, 0.27) and 0.14 ng/dL higher ln(free testosterone) (95%CI 0.00, 0.28), respectively. However, HbGA concentrations had no association with sex hormones in the overall population. Additionally, HbGA/HbAA was negatively associated with TT and SHBG in the overall population as well as postmenopausal women. In stratified analysis, higher HbAA was associated with rising TT in postmenopausal women (β = 0.29, 95%CI 0.04, 0.53) and underweight/normal-weight women (β = 0.18, 95%CI 0.03, 0.33). Other indicators had no significant association detected in estradiol and sex hormone-binding globulin.

CONCLUSION

Our results revealed that HbAA was positively associated with androgen concentrations, especially in postmenopausal and BMI < 25 women.

Serum sex hormone-binding globulin is a mediator of the association between intrahepatic lipid content and type 2 diabetes: the Maastricht Study

AIMS/HYPOTHESIS

Serum sex hormone-binding globulin (SHBG) has been proposed to act as a hepatokine that contributes to the extrahepatic complications observed in non-alcoholic fatty liver disease (NAFLD). However, it remains uncertain whether serum SHBG mediates the association between intrahepatic lipids (IHL) and type 2 diabetes. Therefore, we studied whether, and to what extent, serum SHBG mediates the association between IHL content and type 2 diabetes.

METHODS

We used cross-sectional data from the Maastricht Study (n=1554), a population-based cohort study with oversampling of individuals with type 2 diabetes. Type 2 diabetes status was assessed by oral glucose tolerance test, and IHL content was measured using 3T Dixon MRI. Mediation analyses were performed to assess the role of serum SHBG in mediating the association between IHL content and type 2 diabetes.

RESULTS

IHL content was significantly associated with type 2 diabetes in women and men (OR 1.08 [95% CI 1.04, 1.14] and OR 1.12 [95% CI 1.08, 1.17], respectively). Serum SHBG significantly mediated the association between IHL content and type 2 diabetes. The contribution of serum SHBG was higher in women (OR 1.04 [95% CI 1.02, 1.07]; proportion mediated 50.9% [95% CI 26.7, 81.3]) than in men (OR 1.02 [95% CI 1.01, 1.03]; proportion mediated 17.2% [95% CI 9.6, 27.6]). Repeat analyses with proxies of type 2 diabetes and adjustment for covariates did not substantially affect the results.

CONCLUSIONS/INTERPRETATION

In this large-scale population-based cohort study, serum SHBG was found to be a mediator of the association between IHL content and type 2 diabetes. These findings extend our understanding of the potential mechanisms by which NAFLD is a risk factor for type 2 diabetes, and further elaborate on the role of SHBG as a hepatokine.

First Evidence Indicates the Physiology- and Axial-Myopia-Dependent Profiles of Steroid Hormones in Aqueous Humor

The quantitative level of steroid hormones (SHs) in some body fluids have been accepted for clinical diagnosis, whereas their distribution in aqueous humor (AH) is unknown yet. Herein, a profiling study was conducted with a total of 171 AH and 107 plasma samples using liquid chromatography coupled with tandem mass spectrometry (LC MS/MS). For the first time, six kinds of SHs in AH were quantitatively estimated, and their abundances were ranked at cortisol (F), corticosterone (COR), androstenedione (A2), and 11-deoxycortisol (11DOC). The corresponding abundance of all SHs in AH was significantly lower than those in plasma, while there was a lack of a proportional relationship with the abundance of plasma SHs. Dehydroepiandrosterone sulfate, the most abundant plasma SH, was undetectable in AH, implying that the blood-aqueous barrier might specifically block its transferral. Axial myopia generally results from many factors throughout the entire eye from tissues and molecules; furthermore, the correlation of AH SHs and axial myopia was assessed to look for their indication in such myopia. The panel with five kinds of AH SHs (F, COR, CORT, ALD and A2) was functional as a discriminator for axial myopia and control. The abundance of SHs, therefore, has a specific distribution in AH and can potentially contribute to axial myopia.

Association between de novo lipogenesis susceptibility genes and coronary artery disease

BACKGROUND AND AIMS

Coronary artery disease (CAD) is the principal cause of death in individuals with non-alcoholic fatty liver disease (NAFLD). The aim of this study was to use genetic epidemiology to study the association between de novo lipogenesis (DNL), one of the major pathways leading to NAFLD, and CAD risk.

METHODS AND RESULTS

DNL susceptibility genes were used as instruments and selected using three approaches: 1) genes that are associated with both high serum triglycerides and low sex hormone-binding globulin, both downstream consequences of DNL (unbiased approach), 2) genes that have a known role in DNL (biased approach), and 3) genes that have been associated with serum fatty acids, used as a proxy of DNL. Gene-CAD effect estimates were retrieved from the meta-analysis of CARDIoGRAM and the UK Biobank (∼76014 cases and ∼264785 controls). Effect estimates were clustered using a fixed-effects meta-analysis. Twenty-two DNL susceptibility genes were identified by the unbiased approach, nine genes by the biased approach and seven genes were associated with plasma fatty acids. Clustering of genes selected in the unbiased and biased approach showed a statistically significant association with CAD (OR:1.016, 95%CI:1.012; 1.020 and OR:1.013, 95%CI:1.007; 1.020, respectively), while clustering of fatty acid genes did not (OR:1.004, 95%CI:0.996-1.011). Subsequent exclusion of potential influential outliers did reveal a statistically significant association (OR:1.009, 95%CI:1.000; 1.018).

CONCLUSIONS

DNL susceptibility genes are associated with an increased risk of CAD. These findings suggest that DNL may be involved in the pathogenesis of CAD and favor further development of strategies that target NAFLD through DNL.

Does the Ketogenic Diet Improve the Quality of Ovarian Function in Obese Women?

Background: Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, the prevalence of which ranges from 8 to 13%. It is characterized by metabolic, reproductive, and psychological alterations. PCOS prevalence is related to body mass index (BMI). Women with BMI < 25 kg/m2 have a prevalence of 4.3%, whereas women with BMI > 30 kg/m2 have a prevalence of 14%. Moreover, women with PCOS have a risk of type 2 diabetes mellitus (T2DM) two-fold higher than controls, independently of BMI. Both PCOS and T2DM are also consequences of lower serum sex-hormone-binding globulin (SHBG) levels, which is currently considered a biomarker of metabolic disorders, in particular T2DM. Aim: To evaluate the effect of the very-low-calorie ketogenic diet (VLCKD) on markers suggested to be predictive of metabolic and ovulatory dysfunction. These comprehend SHBG, anti-Mullerian hormone (AMH), and progesterone levels on day 21 of the menstrual cycle in a cohort of obese non-diabetic women with PCOS and regular menses. Methods: Twenty-five patients (mean age 25.4 ± 3.44 years) with obesity and PCOS underwent VLCKD for 12 weeks. Each of them underwent measurements of anthropometric parameters (body weight, height, and waist circumference) and blood testing to evaluate serum levels of SHBG, AMH, and progesterone before and after 12 weeks of VLCKD. Results: At enrollment, all patients had high BMI, WC, and AMH, whereas SHBG and progesterone levels were low. After VLCKD, the patients showed a significant reduction in BMI, WC, and HOMA index. In particular, 76% of patients (19/25) switched from obesity to overweight, and the HOMA index normalized, reaching values lower than 2.5 in 96% (24/25) of patients. In addition, serum AMH levels significantly decreased, and progesterone and SHBG significantly increased after VLCKD. Conclusions: This is the first study documenting the effects of VLCKD on ovarian reserve and luteal function in women with PCOS. VLCKD could be used to improve metabolic and ovulatory dysfunction in women with PCOS. Further studies are needed to understand the reasons for the AMH reduction.

Fructose 1-phosphate, an evolutionary signaling molecule of abundancy

Evidence is accumulating that specifically fructose exerts adverse cardiometabolic effects in humans. Recent experimental studies have shown that fructose not only serves as a substrate for, among others, intrahepatic lipid formation, but also has a signaling function. It is postulated that fructose 1-phosphate (F1-P) has evolved as a signaling molecule of abundancy that stimulates nutrient absorption, lipid storage, and reproduction. Such a role would provide an explanation for why fructose contributes to the pathogenesis of evolutionary mismatch diseases, including nonalcoholic fatty liver disease (NAFLD), cardiovascular disease, polycystic ovary syndrome (PCOS), and colorectal cancer, in the current era of nutritional abundance. It is anticipated that reducing F1-P, by either pharmacological inhibition of ketohexokinase (KHK) or societal measures, will mitigate the risk of these diseases.

The Association Between Circulating Sex Hormones and Central Serous Chorioretinopathy: A Case-Control Study

Background

Central serous chorioretinopathy (CSC) is preferential cocurated in males, however the associations between sex hormones and CSC incidence or progression remains unclear. The sex hormone concentration assessments in CSC cases and healthy controls will update the knowledge in CSC management.

Methods

This case-control study included 59 CSC cases and 30 healthy controls, from January 2019 to December 2020. The CSC cases would be defined as spontaneous resolved if the subretinal fluid were absorbed within three months. The concentrations of total testosterone (TT), free testosterone (FT), estradiol (E2), sex hormone-binding globulin (SHBG), progesterone, leuteinizing hormone (LH) and dehydroepiandrosterone sulfate (DHEA-S) were detected in all the participants. The relationships between sex hormone concentrations and CSC-related characteristics were analyzed with Pearson correlation analyses.

Results

Significantly increased TT, FT, FT/E2 ratio, SHBG concentrations as well as decreased DHEA-S level were detected in non-resolved CSC group compared with the control group. Comparing with the resolved ones, it was found that TT, FT and SHBG concentrations were increased in the non-resolved CSC. A significant positive correlation between TT concentrations and CMT (R²=0.168, P=0.031) as well as SRF height (R²=0.146, P=0.045) were detected in the non-solved CSC group.

Conclusion

Different concentrations of TT, FT, FT/E2 ratio, DHEA-S and SHBG were detected in resolved and non-resolved CSC cases. Sex hormones were related to CSC symptom durations and related parameters.

Contribution of organokines in the development of NAFLD/NASH associated hepatocellular carcinoma

Globally the incidence of hepatocellular carcinoma (HCC) is on an upsurge. Evidence is accumulating that liver disorders like nonalcoholic fatty liver disease (NAFLD) and its more progressive form nonalcoholic steatohepatitis (NASH) are associated with increased risk of developing HCC. NAFLD has a prevalence of about 25% and 50%-90% in obese population. With the growing burden of obesity epidemic worldwide, HCC presents a major healthcare burden. While cirrhosis is one of the major risk factors of HCC, available literature suggests that NAFLD/NASH associated HCC also develops in minimum or noncirrhotic livers. Therefore, there is an urgent need to understand the pathogenesis and risk factors associated with NAFLD and NASH related HCC that would help in early diagnosis and favorable prognosis of HCC secondary to NAFLD. Adipokines, hepatokines and myokines are factors secreted by adipocytes, hepatocytes and myocytes, respectively, playing essential roles in cellular homeostasis, energy balance and metabolism with autocrine, paracrine and endocrine effects. In this review, we endeavor to focus on the role of these organokines in the pathogenesis of NAFLD/NASH and its progression to HCC to augment the understanding of the factors stimulating hepatocytes to acquire a malignant phenotype. This shall aid in the development of novel therapeutic strategies and tools for early diagnosis of NAFLD/NASH and HCC.

Association Between Dietary Inflammatory Index and Sex Hormone Binding Globulin and Sex Hormone in U.S. Adult Females

Context

It is still unknown whether the dietary inflammatory index (DII) is associated with sex hormones and sex hormone binding globulin (SHBG) in adult women.

Objective

This study examined the association between DII and sex hormones and SHBG in U.S. adult women.

Design and Participants

This was a cross-sectional study. A total of 2,092 female participants (age ≥ 20) from the 2013–2016 National Health and Nutrition Examination Survey were enrolled. Dietary inflammatory potential was assessed by DII based on 24-h dietary recall. SHBG was assessed using immuno-antibodies and chemo-luminescence, whereas sex hormones were measured by ID-LC–MS/MS.

Results

The average DII was 0.21 ± 1.68, ranging from −4.54 (most anti-inflammatory) to 4.28 (most pro-inflammatory). After adjusting all covariates, a per-unit DII increase in DII tertile 3 was related to an 8.05 nmol/L SHBG decrease compared to DII tertile 1 (P = 0.0366). Subgroup analysis stratified by perimenopausal period found that this negative association remained strong but only existed in women before (β = −3.71, 95% CI: −7.43, −0.12, P = 0.0423) the perimenopausal period. Interaction terms were added to both subgroup analyses and found no significant heterogeneity among different body mass index (BMI) or perimenopausal groups (P &gt; 0.05). Treshold analyses showed that the association of age with SHBG was an inverted U-shaped curve (inflection point: age = 50 yrs).

Conclusion

A proinflammatory diet caused decreased SHBG. However, more well-designed studies are still needed to validate and verify the causal relationship between DII and sex hormones and SHBG.

Genetic, Molecular, and Cellular Determinants of Sex-Specific Cardiovascular Traits

Despite the well-known sex dimorphism in cardiovascular disease traits, the exact genetic, molecular, and cellular underpinnings of these differences are not well understood. A growing body of evidence currently points at the links between cardiovascular disease traits and the genome, epigenome, transcriptome, and metabolome. However, the sex-specific differences in these links remain largely unstudied due to challenges in bioinformatic methods, inadequate statistical power, analytic costs, and paucity of valid experimental models. This review article provides an overview of the literature on sex differences in genetic architecture, heritability, epigenetic changes, transcriptomic signatures, and metabolomic profiles in relation to cardiovascular disease traits. We also review the literature on the associations between sex hormones and cardiovascular disease traits and discuss the potential mechanisms underlying these associations, focusing on human studies.

Body weight and fat mass across the menopausal transition: hormonal modulators

BACKGROUND

The role of the menopause in weight gain is an understudied yet important field, given the rising prevalence of obesity and its associated risk of disease.

OBJECTIVE

To review the current evidence regarding the impact of the menopausal transition on changes in body composition and fat accrual in women and the hormonal mechanisms underlying the process.

METHODS

A critical appraisal of the current literature by experts in the field.

RESULTS

Menopause is associated with an overall increase in fat mass, which tends to accumulate around the waist. There is also a decrease in lean mass, particularly evident in the lower limbs. Reduced energy expenditure (EE) has been confirmed in parallel with increased food intake, the latter being more evident in experimental models. A prominent role has been found for the estrogen receptor (ER) alpha isoform in fat accrual. Human studies suggest a role for androgens in central fat accumulation and type 2 diabetes. FSH is a key factor in the process of fat accumulation, but only in rodents. Clinical studies suggest that these endocrine alterations are insufficient to explain the observed changes.

CONCLUSIONS

The menopausal transition is associated with an increase in adiposity, which accumulates preferentially in the abdominal area. Hypoestrogenism and the imbalance of the androgen/estrogen ratio are strong candidates to explain the phenomenon, although other hormonal factors probably also play a role. The impact on risk of disease is still insufficiently known, although an association with risk factors, such as an unfavorable lipid profile or insulin resistance seems likely.

Relationship between total testosterone, sex hormone-binding globulin levels and the severity of non-alcoholic fatty liver disease in males: a meta-analysis

BACKGROUND

In recent years, many studies have reported the relationship between non-alcoholic fatty liver disease (NAFLD) and sex hormones, especially total testosterone (TT) and sex hormone-binding globulin (SHBG). However, the relationship between sex hormones and the severity of NAFLD is still unclear.

METHODS

PubMed, Embase, Cochrane Library, Web of Science, WanFang, China National Knowledge Infrastructure and VIP databases were searched for relevant studies from inception to 31 August 2021. Values of weighted mean differences (WMDs) and odds ratios (ORs) with their 95% confidence intervals (CIs) were combined by Stata 12.0 software to evaluate the relationship between TT, SHBG and the severity of NAFLD in males.

RESULTS

A total of 2995 patients with NAFLD from 10 published cross-sectional studies were included for further analysis. The meta-analysis indicated that the moderate-severe group had a lower TT than the mild group in males with NAFLD (WMD: -0.35 ng/ml, 95% CI = -0.50 to -0.20). TT and SHBG were important risk factors of moderate-severe NAFLD in males (OR_TT = 0.79, 95% CI = 0.73 to 0.86; OR_SHBG = 0.22, 95% CI = 0.12 to 0.39; p < 0.001). Moreover, when the analysis was limited to men older than age 50, SHBG levels were lower in those with moderate-severe disease (WMD: -11.32 nmol/l, 95% CI = -14.23 to -8.40); while for men with body mass index (BMI) >27 kg/m², moderate-severe NAFLD had higher SHBG levels than those with mild disease (WMD: 1.20 nmol/l, 95% CI = -2.01 to 4.42).

CONCLUSION

The present meta-analysis shows that lower TT is associated with the severity of NAFLD in males, while the relationship between SHBG and severity of NAFLD is still to be further verified.