Estrogens and Body Weight Regulation in Men

Dual inhibition of aminoacyl-tRNA synthetase interacting multifunctional protein-2 and α-synuclein by steroid derivative is neuroprotective in Parkinson's model

Aminoacyl-tRNA synthetase interacting multifunctional protein-2 (AIMP2), a parkin substrate, possesses self-aggregating properties, potentiating α-synuclein aggregation and neurotoxicity in PD. Thus, targeting both α-synuclein and AIMP2 would present an effective treatment for PD pathologies. Herein, we developed small compounds with dual inhibitory activity against AIMP2 and α-synuclein. Structure-activity relationship (SAR) analysis on commercial and newly synthesized steroid derivatives revealed critical chemical moieties for biological AIMP2 and α-synuclein inhibitory function. Among others, the new compound SG13-136 exhibited strong binding affinity and inhibitory function for both AIMP2 and α-synuclein in vitro. Importantly, in contrast to estriol and other steroids, SG13-136 lacked estrogenic activity, showing no overt toxicity in vivo. Furthermore, SG13-136 demonstrated therapeutic protective effects against PD pathologies in cellular and mouse models of α-synucleinopathy. Our study confirms the strategic validity of targeting both AIMP2 and α-synuclein in PD treatment and offers SAR information that could be used for PD drug discovery.

Linear and non-linear relationships between body fat mass distribution and bone mineral density in adults: The NHANES, 2011-2018

OBJECTIVE

The relationship between body fat mass and bone mineral density (BMD) remains controversial. This research aimed to explore the linear or non-linear relationship between body fat mass and BMD among adults in the United States.

METHODS

This cross-sectional study identified adults aged 18 years or older in the National Health and Nutrition Examination Survey from 2011 to 2018. After adjusting for covariates, linear relationships between body fat mass and BMD in different genders were tested by generalized linear models, and potential non-linear relationships were explored by generalized additive models and piecewise linear regression models.

RESULTS

The research included 4691 (57.9% of the total sample) males and 3417 (42.1% the of total sample) females. In both males and females, we found a negative association between android or total body fat mass and lumbar spine BMD and a positive association between appendicular, android, gynoid, or total body fat mass and whole body BMD (all P < 0.05). The relationships between body fat mass in all regions and lumbar spine BMD were U-shaped in males and inverted U-shaped in females (all Pnon-linear < 0.05). Inverted U-shaped relationships existed between body fat mass in all regions and whole body BMD in females (all Pnon-linear < 0.05).

CONCLUSIONS

Body fat mass was negatively and linearly associated with lumbar spine BMD, but positively associated with whole body BMD. Body fat mass had a U-shaped relationship with lumbar spine BMD in males and an inverted U-shaped association with lumbar spine and whole body BMD in females.

Association between life's essential 8 and testosterone deficiency in US men: findings from national health and nutrition examination survey (NHANES) 2011-2016

Background

Testosterone deficiency (TD) is closely associated with cardiovascular diseases (CVD). We intended to explore the association of Life's Essential 8 (LE8), the recently updated measurement of cardiovascular health, with the prevalence of TD among US male adults.

Methods

The population-based cross-sectional study selected male adults aged 20 years or older from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2016. According to the American Heart Association definitions, the LE8 score was measured on a scale of 0-100, and divided into health behavior and health factor scores, simultaneously. Furthermore, these scores were categorized into low (0-49), moderate (50-79), and high (80-100) classifications. TD is defined as a total testosterone level below 300ng/dL. Correlations were investigated by weighted multivariable logistic regression, and the robustness of the results were verified by subgroup analysis.

Results

A total of 4971 male adults with an average age of 47.46 ± 0.41 years were eligible for the final analyses, of whom 1372 were determined to have TD. The weighted mean LE8 score of the study population was 68.11 ± 0.41. After fully adjusting potential confounders, higher LE8 scores were significantly associated with low risk of TD (odd ratio [OR] for each 10-point increase, 0.79; 95% CI, 0.71-0.88) in a linear dose-response relationship. Similar patterns were also identified in the association of health factor scores with TD (OR for each 10-point increase, 0.74; 95% CI, 0.66-0.83). These results persisted when LE8 and health factor scores was categorized into low, moderate, and high groups. The inversed association of LE8 classifications and TD remained statistically significant among older, obese, and men without CVD.

Conclusions

LE8 and its health factor subscales scores were negatively associated with the presence of TD in linear fashions. Promoting adherence to optimal cardiovascular health levels may be advantageous to alleviate the burden of TD.

The Role of Hypogonadism in the Body Composition of Obese Men in the Preoperative Period of Bariatric Surgery

OBJECTIVE

To describe clinical characteristics, hormonal profile and body composition of obese men in preoperative of bariatric surgery.

METHODS

Cross-sectional, population-based study. Patients evaluated from June 2019 to December 2021 in 2 obesity referral centers. Patients underwent clinical evaluation, androgen deficiency screening using Androgen Deficiency in the Aging Male questionnaire, hormonal profile and body composition assessment through body mass index (BMI), body fat percentage (FM-%) and mass (FM-kg) measured by electrical bioimpedance and dual energy x-ray absorptiometry. To characterize hypogonadism, 2 cut-off points were considered: TT <264 ng/dL and TT <164 ng/dL.

RESULTS

Thirty patients were included, mean age 35.6 ± 8.8 years, mean weight 129.4 ± 14.0 kg and mean BMI 42.3 ± 4.7 kg/m2. Dyslipidemia was the most prevalent comorbidity. Considering TT <264 ng/dL, 22 patients (73%) had hypogonadism. The mean TT in hypogonadal men was 198.9 + 68.7 ng/dL and in eugonadal men 357.0 + 59.5 ng/dl (P < .001). Using TT <164 ng/dL, 7 patients (23%) had hypogonadism. The mean TT in hypogonadal patients was 116.6 + 28.9 ng/dL and in eugonadal patients 279.0 + 75.0 ng/dL (P < .001). In Androgen Deficiency in the Aging Male questionnaire, 93.3% had positive screening, with no significant difference between groups. There was no statistically significant difference in body composition between groups when using TT <264 ng/dL as the hypogonadism cutoff. Considering hypogonadism TT <164 ng/dL, hypogonadal patients had significantly higher values of weight (139.0 × 126.5 kg P = .036), BMI (46.1 × 41.2 kg/m2P = .014), FM-% (48.0 × 42.8% P = .010) and FM-kg (66.3 × 53.9 kg P = .007) than eugonadal patients.

CONCLUSION

Hypogonadism was identified in at least 23% of patients. Considering TT below the lower limit of normality for characterization of hypogonadism, we identified a significant worsening in body composition parameters.

Testosterone therapy reduces insulin resistance in men with adult-onset testosterone deficiency and metabolic syndrome. Results from the Moscow Study, a randomized controlled trial with an open-label phase

AIMS

To describe changes in homeostasis model assessment of insulin resistance index (HOMA-IR) following testosterone therapy in men with hypogonadism and metabolic syndrome (MetS).

MATERIALS AND METHODS

A randomized, placebo-controlled, double-blind randomized controlled trial (RCT) comprising 184 men with MetS and hypogonadism (testosterone undecanoate [TU]: 113 men, placebo: 71 men) was conducted. This was followed by an open-label phase in which all men were given TU. We focused on men who were not receiving antiglycaemic agents (TU: 81 men; placebo: 54 men) as these could affect HOMA-IR. Inter-group comparison of HOMA-IR was restricted to the RCT (30 weeks), whilst intra-group comparison was carried out on men provided TU during the RCT and open-label phases (study cohort) and men given placebo during the RCT and then switched to TU during the open-label phase (confirmatory cohort). Regression analysis was performed to identify factors associated with change in HOMA-IR (∆HOMA-IR).

RESULTS

The median HOMA-IR was significantly reduced at almost every time point (after 18 weeks) compared to baseline in men receiving TU in both the study and confirmatory cohorts. There was a significant decrease in median values of fasting glucose (30 weeks: -2.1%; 138 weeks: -4.9%) and insulin (30 weeks: -10.5%; 138 weeks: -35.5%) after TU treatment. Placebo was not associated with significant ∆HOMA-IR. The only consistent predictor of HOMA-IR decrease following TU treatment was baseline HOMA-IR (r2 ≥ 0.64).

CONCLUSIONS

Baseline HOMA-IR predicted ΔHOMA-IR, with a greater percentage change in insulin than in fasting glucose. In men with MetS/type 2 diabetes (T2DM) not on antiglycaemic therapy, improvements in HOMA-IR may be greater than suggested by change in fasting glucose. Our results suggest that hypogonadism screening be included in the management of men with MetS/T2DM.

Negative correlation between metabolic score for insulin resistance index and testosterone in male adults

BACKGROUND

Insulin resistance (IR) is strongly correlated with the decreased deficiency of testosterone levels in males. The metabolic score for insulin resistance (METS-IR) index is regarded as an innovative measure for the assessment on IR. The research aims to explore the correlation between the METS-IR index and the testosterone levels in males.

METHODS

In this study, a cross-sectional design was made through the data obtained from the National Health and Nutrition Examination Survey (NHANES) from 2013 to 2020. Besides, the METS-IR index was derived from serum triglyceride levels, fasting plasma glucose, HDL-C and BMI.

RESULTS

A total of 2082 participants were included in the final analysis. After controlling for confounding variables, it was found that METS-IR was independently and negatively correlated with testosterone levels (β = -3.88, 95% CI = -4.49, -3.27, P < 0.001). As shown by the generalized smooth curve fitting, METS-IR had a linear correlation with testosterone levels without threshold or saturation effects, which was consistently observed across all subgroups through stratified analysis (all P > 0.05). As revealed by the analysis on the ROC curve, the area under the curve (AUC) for the METS-IR index (0.732, 95% CI = 0.705, 0.760) was significantly larger than that of homeostatic model assessment of insulin resistance (HOMA-IR), TG/HDL ratio, triglyceride-glucose index (TyG) and body mass index (BMI).

CONCLUSION

The findings suggest a negative relationship between the METS-IR index and the testosterone levels in male adults. Furthermore, the METS-IR index demonstrates superior predictive ability for testosterone deficiency in comparison to HOMA-IR, TG/HDL ratio, TyG and BMI.

Fish Oil Improves Offspring Metabolic Health of Paternal Obese Mice by Targeting Adipose Tissue

Obesity is a fast-growing epidemic affecting more than 40% of the US population and leads to co-morbidities such as type 2 diabetes and cancer. More importantly, there is a rapid increase in childhood obesity associated with obesity in parents. Further, offspring are encoded with approximately half of their genetic information from the paternal side. Obesity in fathers at the preconceptional period likely influences the intergenerational development of obesity. This study focuses on the role of fish oil supplementation as a non-pharmacological intervention in fathers and its impact on childhood obesity using animal models. Male mice were fed a low-fat diet or high-fat diet with or without fish oil for 10 weeks and mated with female mice on a chow diet. Offspring were then continued on a chow diet until 8 or 16 weeks. In vivo insulin tolerance was tested to assess the metabolic health of offspring. Further, adipose tissue was harvested upon sacrifice, and genetic markers of inflammation and lipid metabolism in the tissue were analyzed. Offspring of males supplemented with fish oil showed lower body weight, improved insulin tolerance, and altered inflammatory markers. Markers of fatty acid oxidation were higher, while markers of fatty acid synthesis were lower in offspring of fathers fed fish oil. This supports fish oil as an accessible intervention to improve offspring metabolic health.

Exploring the role of testosterone upon adiposity and cardiovascular risk markers in men with severe obesity

A prominent endocrine disorder linked to unhealthy lifestyle behaviors and increased visceral adiposity is Male Obesity Secondary Hypogonadism (MOSH). The pathogenesis of MOSH remains under investigation. However, recent evidence supports a direct role of leptin in affecting Leydig cells, reducing testosterone production, and increasing appetite. Conversely, testosterone deficiency is associated with comorbidities like hypertension, diabetes, and nonalcoholic fatty liver disease. A recently published study entitled “Relationship between sex hormones, markers of adiposity and inflammation in male patients with severe obesity undergoing bariatric surgery” describes evidence supportive of an inverse association between testosterone and serum leptin as well as levels of c-reactive protein (CRP) and IL-6, as well as a correlation between body mass index and CRP. The same study also provides novel insight retrieved from their in vitro findings, which reveal that testosterone exposure influences the expression of genes associated with adiposity, like fatty acid binding protein 4, peroxisome proliferation-activated receptor γ (PPARγ), leptin, and adiponectin, as well as von Willebrand factor, in human-derived adipocytes. Overall, the latest evidence highlights the importance of early identification of hypogonadism in obese males and the potential benefits of testosterone supplementation in alleviating complications associated with obesity, particularly chronic inflammation. These observations underscore the need for a holistic approach to managing severe obesity, addressing hormonal and inflammatory factors to reduce its overall burden on health.

The Biological Basis of Sex Differences in Athletic Performance: Consensus Statement for the American College of Sports Medicine

ABSTRACT

Biological sex is a primary determinant of athletic performance because of fundamental sex differences in anatomy and physiology dictated by sex chromosomes and sex hormones. Adult men are typically stronger, more powerful, and faster than women of similar age and training status. Thus, for athletic events and sports relying on endurance, muscle strength, speed, and power, males typically outperform females by 10%-30% depending on the requirements of the event. These sex differences in performance emerge with the onset of puberty and coincide with the increase in endogenous sex steroid hormones, in particular testosterone in males, which increases 30-fold by adulthood, but remains low in females. The primary goal of this consensus statement is to provide the latest scientific knowledge and mechanisms for the sex differences in athletic performance. This review highlights the differences in anatomy and physiology between males and females that are primary determinants of the sex differences in athletic performance and in response to exercise training, and the role of sex steroid hormones (particularly testosterone and estradiol). We also identify historical and nonphysiological factors that influence the sex differences in performance. Finally, we identify gaps in the knowledge of sex differences in athletic performance and the underlying mechanisms, providing substantial opportunities for high-impact studies. A major step toward closing the knowledge gap is to include more and equitable numbers of women to that of men in mechanistic studies that determine any of the sex differences in response to an acute bout of exercise, exercise training, and athletic performance.

High-Fat Diet Promotes Adipogenesis in Offspring Female Rats Induced by Perinatal Exposure to 4-Nonylphenol

Background

Both high-fat diet (HFD) and 4-nonylphenol (4-NP) could affect fat formation in adipose tissue individually. We investigated whether HFD promote abnormal adipose tissue formation caused by early exposure to 4-NP in life and preliminarily explore the possible mechanisms involved.

Methods

The first-generation rats were treated with HFD on postnatal day after pregnant rats exposure to 5 ug/kg/day 4-NP. Then, the second generation rats started to only receive normal diet without 4-NP or HFD. We analyzed organ coefficient and histopathology of fat tissues, biochemical index, and gene level involved in lipid metabolism in female offspring rats.

Results

HFD and 4-NP interaction synergistically increased birth weight, body weight, and organ coefficients of adipose tissue in offspring female rats. HFD accelerately aggravated abnormal lipid metabolism and increased the adipocyte mean areas around the uterus of the offspring female rats induced by prenatal exposure to 4-NP. HFD also facilitate the regulation of gene expression involved lipid metabolism in offspring female rats induced by perinatal exposure to 4-NP, even passed on to the second generation of female rats. Moreover, HFD and 4-NP interaction synergistically declined the gene and protein expression of estrogen receptor (ER) in the adipose tissue of second-generation female rats.

Conclusion

HFD and 4-NP synergistically regulate the expression of lipid metabolism genes in adipose tissue of F2 female rats and promote adipose tissue generation, leading to obesity in offspring rats, which is closely related to low expression of ER. Therefore, ER genes and proteins may be involved in the synergistic effect of HFD and 4-NP.

A negative association between triglyceride glucose-body mass index and testosterone in adult males: a cross-sectional study

Background and objectives

Insulin resistance (IR) is closely related to the decline or deficiency of testosterone in males. Triglyceride glucose-body mass (TyG-BMI) is considered to be a novel indicator of IR. We conducted this analysis to investigate the association between TyG-BMI and male testosterone, and to explore whether its ability to predict testosterone deficiency is superior to HOMA-IR and TyG.

Methods

This was a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES, 2011-2016). The TyG-BMI index was calculated from serum triglyceride, fasting plasma glucose and BMI. The association of TyG-BMI with male testosterone was estimated by weighted multivariable regression.

Results

We included 3394 participants for the final analysis. After adjusting for confounders, TyG-BMI was found to show an independent negative association with testosterone (β=-1.12, 95%CI: -1.50, -0.75, P<0.0001). Multivariate-adjusted beta also showed testosterone levels were significantly lower in the two highest TyG-BMI group (Q3, Q4) compared to the lowest group (Q1). Similar results were seen in all of the subgroup populations by stratified analysis (all P-interaction >0.05). Furthermore, ROC curve analysis indicated that the area under the curve of TyG-BMI index (0.73, 95% CI: 0.71, 0.75) was larger than that of HOMA-IR index (0.71, 95% CI: 0.69, 0.73) and TyG index (0.66, 95% CI: 0.64, 0.68).

Conclusion

Our result suggested a negative association between TyG-BMI index and testosterone in adult males. The predictability of the TyG-BMI index for testosterone deficiency is better than that of HOMA-IR index and TyG index.

Association of Blood Total Mercury with Dyslipidemia in a sample of U.S. Adolescents: Results from the National Health and Nutrition Examination Survey Database, 2011-2018

Background

Abnormal lipid profiles in adolescents predict metabolic and cardiovascular diseases in adulthood. While seafood consumption is the primary source of mercury exposure, it also provides beneficial nutrients such as omega-3 fatty acids (O3FA). Prior studies indicate that blood total mercury (TBHg) has endocrine disrupting effects and may be associated with abnormal lipid profiles in adolescents. However, the impact of beneficial nutrients on this relationship has not been examined. Our study investigated the relationship of TBHg with dyslipidemia and lipid profiles and potential confounding and modification of these relationships by sex, body mass index (BMI), selenium and O3FA from seafood consumption.

Methods

We examined 1,390 National Health and Nutrition Examination Survey participants 12-19 years of age from the 2011-2018 cycles. Using logistic and linear regression adjusted for survey design variables and stratified by sex a priori, we estimated the associations of TBHg and methylmercury with dyslipidemia, and with total cholesterol (TC), high (HDL-C) and low-density lipoprotein cholesterol (LDL-C) and triglycerides.

Results

The geometric mean of TBHg in this adolescent population was 0.44 μg/L. After controlling for socio-demographic covariates, BMI, serum selenium, age at menarche (females only) and average daily intake of O3FA; TBHg was significantly associated with higher TC levels (β=3.34, 95% CI: 0.19, 6.50; p<0.05) in females but not males. Methyl Hg was also associated with increased TC, as well as decreased HDL-C in females but not males. We did not find significant associations of Hg exposure with dyslipidemia, LDL-C or triglycerides levels in either male or female adolescents. However, we observed evidence of effect modification by BMI and serum selenium for associations of TBHg with TC levels in male and female adolescents, respectively.

Conclusion

Our findings of elevated TC levels in females but not males necessitates further research to better understand the underlying mechanisms driving these sex-specific associations.

Relationship between testosterone-estradiol ratio and some anthropometric and metabolic parameters among Nigerian men

Background

Alterations in sex hormone levels are implicated in the regulation of metabolic processes in men. In recent years, the prevalence of metabolic disorders, such as obesity, insulin resistance, and type 2 diabetes, has risen in Nigeria. In men, these disorders may be associated with the ratio of serum testosterone to estradiol levels. Therefore, we investigated the relationship between the testosterone-estradiol (T/E2) ratio, anthropometry, and metabolic parameters in Nigerian men.

Method

Eighty-five adult men were recruited for this study. Participants' data such as age, weight, height, BMI, and waist circumference were collected. Plasma total testosterone and estradiol levels, as well as metabolic parameters such as fasting blood sugar, creatinine, urea, HDL cholesterol, total cholesterol, and triglycerides levels, were determined. The data were analyzed using SPSS version 25 software.

Results

Anthropometric parameters such as weight, height, BMI, and waist circumference showed a negative correlation with plasma T/E2 (r = -0.265, -0.288, -0.106, -0.204; p = 0.007, 0.004, 0.167, 0.061 respectively). However, the T/E2 ratio showed a positive correlation with the metabolic parameters such as fasting blood sugar, HDL cholesterol levels, plasma creatinine, and urea (r = 0.219, 0.096, 0.992, 0.152; p = 0.022, 0.192, <0.001, 0.082 respectively), while there were negative correlations with total cholesterol and triglycerides levels (r = -0.200, -0.083; p = 0.034, 0.226 respectively).

Conclusion

These findings show that there are significant correlations between the T/E2 ratio and weight, height, fasting blood sugar, creatinine, and urea, while there are no significant correlations between T/E2 ratio and BMI, waist circumference, HDL-cholesterol, and triglycerides.

Feminizing Adrenocortical Tumor with Multiple Recurrences: A Case Report

Feminizing adrenocortical tumors (FATs) are exceptionally rare primary adrenal neoplasms that cause high estrogen and low testosterone levels. They are most common in adult males, typically presenting with gynecomastia, hypogonadism, and weight loss. They are almost always malignant, with a poor prognosis and a high recurrence rate. We report a case of a 35-year-old man with an adrenal FAT with high estrogen (181 pg/mL) and low testosterone (37 ng/dL) who presented with gynecomastia, erectile dysfunction, subclinical Cushing syndrome, and pain localizing to different regions of the torso. There was no evidence of metastatic disease initially as seen by visualization of a well-marginated mass on computed tomography scan. Surgical resection of the FAT was performed, and the mass was confirmed to be a low-grade tumor. Clinical symptoms were resolved after surgery. Despite complete resection with negative margins, the patient subsequently had two separate local metastatic recurrences within a few years, treated with a combination of further surgery and medical intervention. This case highlights the unique features of an exceedingly rare adrenal tumor and stresses the importance of early detection and vigilant surveillance following resection due to high recurrence rates.

Phosphorylation of S122 in ERα is important for the skeletal response to estrogen treatment in male mice

Estrogen receptor alpha (ERα) signaling has beneficial skeletal effects in males. ERα signaling also affects other tissues, and to find bone-specific treatments, more knowledge regarding tissue-specific ERα signaling is needed. ERα is subjected to posttranslational modifications, including phosphorylation, which can influence ERα function in a tissue-specific manner. To determine the importance of phosphorylation site S122 (corresponding to human ERα site S118) for the skeleton and other tissues, male mice with a S122A mutation were used. Total areal bone mineral density was similar between gonadal intact S122A and WT littermates followed up to 12 months of age, and weights of estrogen-responsive organs normalized for body weight were unchanged between S122A and WT males at both 3 and 12 months of age. Interestingly, 12-month-old S122A males had decreased body weight compared to WT. To investigate if site S122 affects the estrogen response in bone and other tissues, 12-week-old S122A and WT males were orchidectomized (orx) and treated with estradiol (E2) or placebo pellets for four weeks. E2 increased cortical thickness in tibia in both orx WT (+ 60%, p < 0.001) and S122A (+ 45%, p < 0.001) males. However, the E2 effect on cortical thickness was significantly decreased in orx S122A compared to WT mice (- 24%, p < 0.05). In contrast, E2 affected trabecular bone and organ weights similarly in orx S122A and WT males. Thus, ERα phosphorylation site S122 is required for a normal E2 response specifically in cortical bone in male mice, a finding that may have implications for development of future treatments against male osteoporosis.

The Roles of Androgens in Humans: Biology, Metabolic Regulation and Health

Androgens are an important and diverse group of steroid hormone molecular species. They play varied functional roles, such as the control of metabolic energy fate and partition, the maintenance of skeletal and body protein and integrity and the development of brain capabilities and behavioral setup (including those factors defining maleness). In addition, androgens are the precursors of estrogens, with which they share an extensive control of the reproductive mechanisms (in both sexes). In this review, the types of androgens, their functions and signaling are tabulated and described, including some less-known functions. The close interrelationship between corticosteroids and androgens is also analyzed, centered in the adrenal cortex, together with the main feedback control systems of the hypothalamic-hypophysis-gonads axis, and its modulation by the metabolic environment, sex, age and health. Testosterone (T) is singled out because of its high synthesis rate and turnover, but also because age-related hypogonadism is a key signal for the biologically planned early obsolescence of men, and the delayed onset of a faster rate of functional losses in women after menopause. The close collaboration of T with estradiol (E2) active in the maintenance of body metabolic systems is also presented Their parallel insufficiency has been directly related to the ravages of senescence and the metabolic syndrome constellation of disorders. The clinical use of T to correct hypoandrogenism helps maintain the functionality of core metabolism, limiting excess fat deposition, sarcopenia and cognoscitive frailty (part of these effects are due to the E2 generated from T). The effectiveness of using lipophilic T esters for T replacement treatments is analyzed in depth, and the main problems derived from their application are discussed.

Association of dietary and nutrient patterns with systemic inflammation in community dwelling adults

Purpose

Evidence investigating associations between dietary and nutrient patterns and inflammatory biomarkers is inconsistent and scarce. Therefore, we aimed to determine the association of dietary and nutrient patterns with inflammation.

Methods

Overall, 1,792 participants from the North-West Adelaide Health Study were included in this cross-sectional study. We derived dietary and nutrient patterns from food frequency questionnaire data using principal component analysis. Multivariable ordinal logistic regression determined the association between dietary and nutrient patterns and the grade of inflammation (normal, moderate, and severe) based on C-reactive protein (CRP) values. Subgroup analyses were stratified by gender, obesity and metabolic health status.

Results

In the fully adjusted model, a plant-sourced nutrient pattern (NP) was strongly associated with a lower grade of inflammation in men (OR_Q5vsQ1 = 0.59, 95% CI: 0.38–0.93, p-trend = 0.08), obesity (OR_Q5vsQ1 = 0.43; 95% CI: 0.24–0.77, p-trend = 0.03) and metabolically unhealthy obesity (OR_Q5vsQ1 = 0.24; 95% CI: 0.11–0.52, p-trend = 0.01). A mixed NP was positively associated with higher grade of inflammation (OR_Q5vsQ1 = 1.35; 95% CI: 0.99–1.84, p-trend = 0.03) in all participants. A prudent dietary pattern was inversely associated with a lower grade of inflammation (OR_Q5vsQ1 = 0.72, 95% CI: 0.52–1.01, p-trend = 0.14). In contrast, a western dietary pattern and animal-sourced NP were associated with a higher grade of inflammation in the all participants although BMI attenuated the magnitude of association (OR_Q5vsQ1 = 0.83, 95% CI: 0.55–1.25; and OR_Q5vsQ1 = 0.94, 95% CI: 0.63–1.39, respectively) in the fully adjusted model.

Conclusion

A plant-sourced NP was independently associated with lower inflammation. The association was stronger in men, and those classified as obese and metabolically unhealthy obese. Increasing consumption of plant-based foods may mitigate obesity-induced inflammation and its consequences.

Skinny people serum factors promote the differentiation of multipotent stem cells into brown adipose tissue

The original study by Alessio et al reported that skinny people (SP) serum can promote the formation of brown adipocytes, but not the differentiation of white adipocytes. This finding may explain why SP do not often become obese, despite consuming more calories than the body needs. More importantly, they demonstrated that circulating factors in SP serum can promote the expression of UCP-1 protein, thereby reducing fat accumulation. In this study, only male serum samples were evaluated to avoid the interference of sex hormones in experiments, but adult males also synthesize estrogen, which is produced by the cells of the testes. At the same time, adult females secrete androgens, and females synthesize androgens that are mainly produced by the adrenal cortex. We believe that the approach of excluding sex hormone interference by sex selection alone may be flawed, so we comment on the article and debate the statistical analysis of the article.

Sex hormones, adiposity, and metabolic traits in men and women: a Mendelian randomisation study

OBJECTIVE

Epidemiological and clinical studies have highlighted important roles for sex hormones in the regulation of fat distribution and systemic metabolism. We investigated the bidirectional associations between bioavailable serum testosterone (BioT) in both sexes and oestradiol (E2) in men and adiposity and metabolic traits using Mendelian randomisation (MR).

DESIGN AND METHODS

As genetic instruments for sex hormones, we selected all the genome-wide significant, independent signals from a genome-wide association studies (GWAS) in up to 425 097 European ancestry UK Biobank participants. European population-specific, summary-level data for adiposity, metabolic, and blood pressure traits were obtained from the largest publicly available GWAS. Sex-specific, two-sample MR analyses were used to estimate the associations of sex hormones with these traits and vice versa.

RESULTS

In women, higher BioT was associated with obesity, upper-body fat distribution, and low HDL-cholesterol although, based on analyses modelling the sex hormone-binding globulin-independent effects of BioT, the last two associations might be indirect. Conversely, obesity and android fat distribution were associated with elevated serum BioT. In men, higher BioT was associated with lower hip circumference and lower fasting glucose. Reciprocally, obesity was associated with lower BioT and higher E2, while upper-body fat distribution and raised triglycerides were associated with lower E2.

CONCLUSIONS

Adipose tissue and metabolic dysfunction are associated with deranged sex hormone levels in both sexes. In women, elevated BioT might be a cause of obesity. Conversely, in men, higher BioT appears to have beneficial effects on adiposity and glucose metabolism.

The associations between body fat distribution and bone mineral density in the Oxford Biobank: a cross sectional study

BACKGROUND

Body composition is associated with bone mineral density (BMD), but the precise associations between body fat distribution and BMD remain unclear. The regional adipose tissue depots have different metabolic profiles. We hypothesized that they would have independent associations with BMD.

RESEARCH DESIGN AND METHODS

We used data from 4,900 healthy individuals aged 30-50 years old from the Oxford Biobank to analyze associations between regional fat mass, lean mass and total BMD.

RESULTS

Total lean mass was strongly positively associated with BMD. An increase in total BMD was observed with increasing mass of all the fat depots, as measured either by anthropometry or DXA, when accounting for lean mass. However, on adjustment for both total fat mass and lean mass, fat depot specific associations emerged. Increased android and visceral adipose tissue mass in men, and increased visceral adipose tissue mass in women, were associated with lower BMD.

CONCLUSIONS

Fat distribution alters the association between adiposity and BMD.

Obesity, Body Composition, and Sex Hormones: Implications for Cardiovascular Risk

Cardiovascular disease (CVD) continues to be the leading cause of death in adults, highlighting the need to develop novel strategies to mitigate cardiovascular risk. The advancing obesity epidemic is now threatening the gains in CVD risk reduction brought about by contemporary pharmaceutical and surgical interventions. There are sex differences in the development and outcomes of CVD; premenopausal women have significantly lower CVD risk than men of the same age, but women lose this advantage as they transition to menopause, an observation suggesting potential role of sex hormones in determining CVD risk. Clear differences in obesity and regional fat distribution among men and women also exist. While men have relatively high fat in the abdominal area, women tend to distribute a larger proportion of their fat in the lower body. Considering that regional body fat distribution is an important CVD risk factor, differences in how men and women store their body fat may partly contribute to sex-based alterations in CVD risk as well. This article presents findings related to the role of obesity and sex hormones in determining CVD risk. Evidence for the role of sex hormones in determining body composition in men and women is also presented. Lastly, the clinical potential for using sex hormones to alter body composition and reduce CVD risk is outlined. © 2022 American Physiological Society. Compr Physiol 12:1-45, 2022.

Overfeeding-induced weight gain elicits decreases in sex hormone-binding globulin in healthy males-Implications for body fat distribution

OBJECTIVE

Obesity and upper-body fat elevates cardiometabolic risk. However, mechanisms predisposing to upper-body fat accumulation are not completely understood. In males, low testosterone (T) frequently associates with obesity, and estrogen deficiency may contribute to upper-body adiposity. This study examines the effects of overfeeding-induced weight gain on changes in gonadal hormones in healthy males and its association with regional fat depots.

METHODS

Twenty-five males (age: 29.7 ± 6.9 years; BMI: 24.7 ± 3.1 kg/m2 ) were overfed for 8 weeks to gain approximately 5% body weight. Changes in total and regional fat depots were assessed using dual-energy x-ray absorptiometry and abdominal computed tomography scans. Circulating T, estrone (E1), 17-β estradiol (E2), and sex hormone-binding globulin (SHBG) concentrations were measured at baseline and after weight gain.

RESULTS

Overfeeding resulted in 3.8 (3.3, 4.9) kg weight gain with increased total body fat. Weight gain did not alter circulating T (p = 0.82), E1 (p = 0.52), or E2 (p = 0.28). However, SHBG decreased (p = 0.04) along with consequent increases in T/SHBG (p = 0.02) and E2/SHBG (p = 0.03) ratios. Importantly, baseline E2/SHBG ratio was inversely associated with increases in upper-body fat mass (ρ = -0.43, p = 0.03).

CONCLUSIONS

Modest weight gain does not alter circulating gonadal hormones in males but may increase bioavailability of T and E2 via decreases in SHBG. The association between baseline E2/SHBG and regional fat mass suggests that higher levels of bioavailable E2 may protect from upper-body fat accumulation during overfeeding-induced modest weight gain in healthy males. Our study suggests a complex relationship between adipose tissue, gonadal hormones, and fat accumulation in males.

A virus-free cellular model recapitulates several features of severe COVID-19

As for all newly-emergent pathogens, SARS-CoV-2 presents with a relative paucity of clinical information and experimental models, a situation hampering both the development of new effective treatments and the prediction of future outbreaks. Here, we find that a simple virus-free model, based on publicly available transcriptional data from human cell lines, is surprisingly able to recapitulate several features of the clinically relevant infections. By segregating cell lines (n = 1305) from the CCLE project on the base of their sole angiotensin-converting enzyme 2 (ACE2) mRNA content, we found that overexpressing cells present with molecular features resembling those of at-risk patients, including senescence, impairment of antibody production, epigenetic regulation, DNA repair and apoptosis, neutralization of the interferon response, proneness to an overemphasized innate immune activity, hyperinflammation by IL-1, diabetes, hypercoagulation and hypogonadism. Likewise, several pathways were found to display a differential expression between sexes, with males being in the least advantageous position, thus suggesting that the model could reproduce even the sex-related disparities observed in the clinical outcome of patients with COVID-19. Overall, besides validating a new disease model, our data suggest that, in patients with severe COVID-19, a baseline ground could be already present and, as a consequence, the viral infection might simply exacerbate a variety of latent (or inherent) pre-existing conditions, representing therefore a tipping point at which they become clinically significant.

The Impact of Estrogen and Estrogen-Like Molecules in Neurogenesis and Neurodegeneration: Beneficial or Harmful?

Estrogens and estrogen-like molecules can modify the biology of several cell types. Estrogen receptors alpha (ERα) and beta (ERβ) belong to the so-called classical family of estrogen receptors, while the G protein-coupled estrogen receptor 1 (GPER-1) represents a non-classical estrogen receptor mainly located in the plasma membrane. As estrogen receptors are ubiquitously distributed, they can modulate cell proliferation, differentiation, and survival in several tissues and organs, including the central nervous system (CNS). Estrogens can exert neuroprotective roles by acting as anti-oxidants, promoting DNA repair, inducing the expression of growth factors, and modulating cerebral blood flow. Additionally, estrogen-dependent signaling pathways are involved in regulating the balance between proliferation and differentiation of neural stem/progenitor cells (NSPCs), thus influencing neurogenic processes. Since several estrogen-based therapies are used nowadays and estrogen-like molecules, including phytoestrogens and xenoestrogens, are omnipresent in our environment, estrogen-dependent changes in cell biology and tissue homeostasis have gained attention in human health and disease. This article provides a comprehensive literature review on the current knowledge of estrogen and estrogen-like molecules and their impact on cell survival and neurodegeneration, as well as their role in NSPCs proliferation/differentiation balance and neurogenesis.

Health benefits attributed to 17α-estradiol, a lifespan-extending compound, are mediated through estrogen receptor α

Metabolic dysfunction underlies several chronic diseases, many of which are exacerbated by obesity. Dietary interventions can reverse metabolic declines and slow aging, although compliance issues remain paramount. 17α-estradiol treatment improves metabolic parameters and slows aging in male mice. The mechanisms by which 17α-estradiol elicits these benefits remain unresolved. Herein, we show that 17α-estradiol elicits similar genomic binding and transcriptional activation through estrogen receptor α (ERα) to that of 17β-estradiol. In addition, we show that the ablation of ERα completely attenuates the beneficial metabolic effects of 17α-E2 in male mice. Our findings suggest that 17α-E2 may act through the liver and hypothalamus to improve metabolic parameters in male mice. Lastly, we also determined that 17α-E2 improves metabolic parameters in male rats, thereby proving that the beneficial effects of 17α-E2 are not limited to mice. Collectively, these studies suggest ERα may be a drug target for mitigating chronic diseases in male mammals.

Adjuvant treatment of early male breast cancer

PURPOSE OF REVIEW

Male breast cancer (MaBC) is a rare disease, and some challenges exist in its management because current treatment recommendations are extrapolated from trials that mostly excluded men. This review will revise all available data that could improve the treatment of MaBC, with a special focus on adjuvant systemic treatments.

RECENT FINDINGS

To date, men with hormone receptor-positive breast cancer, who are candidates for adjuvant endocrine therapy, should be offered tamoxifen (TAM) for five years. Additional five years are possible, according to tolerance and recurrence risk. If TAM is contraindicated, a gonadotropin-releasing hormone (GnRH) agonist or antagonist and aromatase inhibitor should be proposed. Chemotherapy and targeted therapy in the other breast cancer subtypes should be used with the same indications offered to women with breast cancer. All men with breast cancer should be offered genetic counseling and germline genetic testing of cancer predisposition genes.

SUMMARY

For decades, men with breast cancer have been treated suboptimally and denied the participation in clinical trials. Recently, many clinical trials started enrolling both genders, as strongly endorsed by the Food and Drug Administration. Hopefully, this turnaround will help subdue the disparities in the quality of care.

Estrogen Receptor beta (ERβ) Regulation of Lipid Homeostasis-Does Sex Matter?

In this communication, we aim to summarize the role of estrogen receptor beta (ERβ) in lipid metabolism in the main metabolic organs with a special focus on sex differences. The action of ERβ is tissue-specific and acts in a sex-dependent manner, emphasizing the necessity of developing sex- and tissue-selective targeting drugs in the future.

Dimorphic effect of 17β-oestradiol on pathology and oxidative stress in experimental malaria

Malaria is the parasitic disease with the highest mortality worldwide; males exhibit higher mortality and more severe symptomatology than females, suggesting the participation of sexual hormones in protection and pathology. We have documented that gonadectomy modifies oxidative stress in Plasmodium berghei ANKA-infected mice in a dimorphic manner. However, gonadectomy decreases all sexual steroids levels, making it difficult to determine the contribution of each hormone to the results. This study aimed to explore the participation of 17β-oestradiol (E2) in oxidative stress in the blood, spleen, liver and brain of P. berghei-infected female and male mice. E2 was administered to intact or gonadectomized (GX) male and female mice to assess their effects on parasitaemia, body weight loss and hypothermia. We also measured the effect of E2 on the specific activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) and on malondialdehyde (MDA) levels in the blood, spleen, liver and brain of CBA/Ca male and female mice infected with P. berghei ANKA. We detected the effects of E2 and sexual dimorphism on all tissues and variables analysed. Administration of E2 increased parasitaemia in intact mice. However, reconstitution of GX female mice with E2 decreased parasitaemia. E2 decreased body weight and differentially modulated oxidative stress depending on the sex, infection and tissue analysed. Low antioxidant activity was detected in the brain, suggesting additional protective antioxidant mechanisms in the brain independent of antioxidant enzymes. Our results explained, at least in part, the sexual dimorphism in this experimental model of malaria.

Novel causes and consequences of overtraining syndrome: the EROS-DISRUPTORS study

Background

Hormonal physiology in athletes, dysfunctional paths leading to overtraining syndrome (OTS), and clinical and biochemical behaviors that are independently modified by the presence of OTS remain unclear. Although multiple markers of OTS have recently been identified, the independent influence of OTS on hormones and metabolism have not been assessed. Hence, the objective of the present study was to uncover the previously unrecognized independent predictors of OTS and understand how OTS independently modifies the behaviors of clinical and biochemical parameters.

Methods

In a total of 39 athletes (OTS-affected athletes (OTS) = 14 and healthy athletes (ATL) = 25), we performed two clusters of statistical analyses using the full data of the Endocrine and Metabolic Responses on Overtraining Syndrome (EROS) study, in a total of 117 markers. We first used logistic regression to analyze five modifiable parameters (carbohydrate, protein, and overall caloric intake, sleep quality, and concurrent cognitive effort) as potential additional independent risk factors for OTS, and OTS as the outcome. We then used multivariate linear regression to analyze OTS as the independent variable and 38 dependent variables. Training patterns were found to be similar between OTS and ATL, and therefore excessive training was not a risk, and consequently not a predictor, for OTS.

Results

Each of the three dietary patterns (daily carbohydrate, daily protein, and daily overall calorie intake) were found to be the independent triggers of OTS, while sleeping, social, and training characteristics depended on other factors to induce OTS. Once triggered, OTS independently induced multiple changes, including reductions of cortisol, late growth hormone and adrenocorticotropic hormone responses to stimulations, testosterone-to-estradiol ratio, neutrophils, neutrophil-to-lymphocyte ratio, vigor levels, hydration status, and muscle mass, while increase of tension levels and visceral fat.

Conclusions

OTS can be independently triggered by eating patterns, regardless of training patterns, while the occurrence of OTS reduced late hormonal responses and the testosterone-to-estradiol ratio, worsened mood, and affected the immunology panel. These novel findings may explain underperformance, which is the key characteristic of OTS.

Role of Complement and Complement-Related Adipokines in Regulation of Energy Metabolism and Fat Storage

Adipose tissue releases many cytokines and inflammatory factors described as adipokines. In obesity, adipokines released from expanding adipose tissue are implicated in disease progression and metabolic dysfunction. However, mechanisms controlling the progression of adiposity and metabolic complications are not fully understood. It has been suggested that expanding fat mass and sustained release of inflammatory adipokines in adipose tissue lead to hypoxia, oxidative stress, apoptosis, and cellular damage. These changes trigger an immune response involving infiltration of adipose tissue with immune cells, complement activation and generation of factors involved in opsonization and clearance of damaged cells. Abundant evidence now indicates that adipose tissue is an active secretory source of complement and complement-related adipokines that, in addition to their inflammatory role, contribute to the regulation of metabolic function. This article highlights advances in knowledge regarding the role of these adipokines in energy regulation of adipose tissue through modulating lipogenic and lipolytic pathways. Several adipokines will be discussed including adipsin, Factor H, properdin, C3a, Acylation-Stimulating Protein, C1q/TNF-related proteins, and response gene to complement-32 (RGC-32). Interactions between these factors will be described considering their immune-metabolic roles in the adipose tissue microenvironment and their potential contribution to progression of adiposity and metabolic dysfunction. The differential expression and the role of complement factors in gender-related fat partitioning will also be addressed. Identifying lipogenic adipokines and their specific autocrine/paracrine roles may provide means for adipose-tissue-targeted therapeutic interventions that may disrupt the vicious circle of adiposity and disease progression. © 2019 American Physiological Society. Compr Physiol 9:1411-1429, 2019.

Obesity and male hypogonadism: Tales of a vicious cycle

Obesity prevalence, particularly in children and young adults, is perilously increasing worldwide foreseeing serious negative health impacts in the future to come. Obesity is linked to impaired male gonadal function and is currently a major cause of hypogonadism. Besides signs and symptoms directly derived from decreased circulating testosterone levels, males with obesity also present poor fertility outcomes, further evidencing the parallelism between obesity and male reproductive function. In addition, males with androgen deficiency also exhibit increased fat accumulation and reduced muscle and mineral bone mass. Thus, compelling evidence highlights a vicious cycle where male hypogonadism can lead to increased adiposity, while obesity can be a cause for male hypogonadism. On the opposite direction, sustained weight loss can attain amelioration of male gonadal function. In this scenario, a thorough evaluation of gonadal function in men with obesity is crucial to dissect the causes from the consequences in order to target clinical interventions towards maximized improvement of reproductive health. This review will address the causes and consequences of the bidirectional relationship between obesity and hypogonadism, highlighting the implicit male reproductive repercussions.

Obesity and Fat Metabolism in Human Immunodeficiency Virus-Infected Individuals: Immunopathogenic Mechanisms and Clinical Implications

Metabolic complications relating to complex effects of viral and immune-mediated mechanisms are now a focus of clinical care among persons living with human immunodeficiency virus (PLHIV), and obesity is emerging as a critical problem. To address knowledge gaps, the US National Institutes of Health sponsored a symposium in May 2018 entitled "Obesity and Fat Metabolism in HIV-infected Individuals." Mechanisms relating to adipose dysfunction and fibrosis, immune function, inflammation, and gastrointestinal integrity were highlighted as contributors to obesity among PLHIV. Fibrotic subcutaneous adipose tissue is metabolically dysfunctional and loses its capacity to expand, leading to fat redistribution, including visceral obesity and ectopic fat accumulation, promoting insulin resistance. Viral proteins, including viral protein R and negative regulatory factor, have effects on adipogenic pathways and cellular metabolism in resident macrophages and T cells. HIV also affects immune cell trafficking into the adipose compartments, with effects on adipogenesis, lipolysis, and ectopic fat accumulation. Key cellular metabolic functions are likely to be affected in PLHIV by gut-derived cytokines and altered microbiota. There are limited strategies to reduce obesity specifically in PLHIV. Enhancing our understanding of critical pathogenic mechanisms will enable the development of novel therapeutics that may normalize adipose tissue function and distribution, reduce inflammation, and improve insulin sensitivity in PLHIV.

Drug-drug interactions between feminizing hormone therapy and pre-exposure prophylaxis among transgender women: the iFACT study

INTRODUCTION

Concerns over potential drug-drug interactions (DDI) between feminizing hormone therapy (FHT) and pre-exposure prophylaxis (PrEP) have hampered uptake and adherence of PrEP among transgender women (TGW). To determine DDI between FHT and PrEP, we measured the pharmacokinetic (PK) parameters of blood plasma estradiol (E2) and tenofovir (TFV) in Thai TGW.

METHODS

Twenty TGW who never underwent orchiectomy and had not received injectable FHT within six months were enrolled between January and March 2018. FHT (E2 valerate and cyproterone acetate) were prescribed to participants at baseline until week 5, and then from week 8 until the end of study. Daily PrEP (tenofovir disoproxil fumarate/emtricitabine) was initiated at week 3 and continued without interruption. Intensive E2 PK parameters and testosterone concentration at 24 hours (C24 ) were measured at weeks 3 (without PrEP) and 5 (with PrEP), and intensive TFV PK parameters were measured at weeks 5 (with FHT) and 8 (without FHT).

RESULTS

Median (interquartile range) age, body mass index, and creatinine clearance were 21.5 (21-26) years, 20.6 (19.0-22.4) kg/m2 , and 116 (101-126.5) mL/min, respectively. The geometric mean (%CV) of area under curve from time zero to 24 hours (AUC0-24 ), maximum concentration (Cmax ), and C24 of E2 at weeks 3 and 5 were 775.13 (26.2) pg h/mL, 51.47 (26.9) pg/mL, and 15.15 (42.0) pg/mL; and 782.84 (39.6), 55.76 (32.9), and 14.32 (67.4), respectively. The geometric mean (%CV) of TFV AUC0-24 , Cmax , and C24 at weeks 5 and 8 were 2242.1 (26.5) ng h/mL, 353.9 (34.0) ng/mL, and 40.9 (31.4) ng/mL; and 2530.2 (31.3), 311.4 (30.0), and 49.8 (29.6), respectively. The geometric mean of TFV AUC0-24 and C24 at week 5 were significantly less than that at week 8 by 12% (p = 0.03) and 18% (p < 0.001), respectively. There were no significant changes in E2 PK parameters and median C24 of bioavailable testosterone between week 3 and week 5.

CONCLUSIONS

Our study demonstrated lower blood plasma TFV exposure in the presence of FHT, suggesting that FHT may potentially affect PrEP efficacy among TGW; but E2 exposure was not affected by PrEP. Further studies are warranted to determine whether these reductions in TFV are clinically significant. Clinical Trial Number: NCT03620734.

Disruption of ESR1 alters the expression of genes regulating hepatic lipid and carbohydrate metabolism in male rats

The liver helps maintain energy homeostasis by synthesizing and storing glucose and lipids. Gonadal steroids, particularly estrogens, play an important role in regulating metabolism. As estrogens are considered female hormones, metabolic disorders related to the disruption of estrogen signaling have mostly been studied in females. Estrogen receptor alpha (ESR1) is the predominant receptor in both the male and female liver, and it mediates the hepatic response to estrogens. Loss of ESR1 increases weight gain and obesity in female rats, while reducing the normal growth in males. Although Esr1-/- male rats have a reduced body weight, they exhibit increased adipose deposition and impaired glucose tolerance. We further investigated whether these metabolic disorders in Esr1-/- male rats were linked with the loss of transcriptional regulation by ESR1 in the liver. To identify the ESR-regulated genes, RNA-sequencing was performed on liver mRNAs from wildtype and Esr1-/- male rats. Based on an absolute fold change of ≥2 with a p-value ≤ 0.05, a total of 706 differentially expressed genes were identified in the Esr1-/- male liver: 478 downregulated, and 228 upregulated. Pathway analyses demonstrate that the differentially expressed genes include transcriptional regulators (Cry1, Nr1d1, Nr0b2), transporters (Slc1a2), and regulators of biosynthesis (Cyp7b1, Cyp8b1), and hormone metabolism (Hsd17b2, Sult1e1). Many of these genes are also integral parts of the lipid and carbohydrate metabolism pathways in the liver. Interestingly, certain critical regulators of the metabolic pathways displayed a sexual dimorphism in expression, which may explain the divergent weight gain in Esr1-/- male and female rats despite common metabolic dysfunctions.

Possible role of phytoestrogens in breast cancer via GPER-1/GPR30 signaling

Estrogens generated within endocrine organs and the reproductive system act as ligands for at least three types of estrogen receptors. Estrogen receptors α (ERα) and β (ERβ) belong to the so-called classical family of estrogen receptors, whereas the G protein-coupled receptor GPR30, also known as GPER-1, has been described as a novel estrogen receptor sited in the cell membrane of target cells. Furthermore, these receptors are under stimulation of a family of exogenous estrogens, known as phytoestrogens, which are a diverse group of non-steroidal plant compounds derived from plant food consumed by humans and animals. Because phytoestrogens are omnipresent in our daily diet, they are becoming increasingly important in both human health and disease. Recent evidence indicates that in addition to classical estrogen receptors, phytoestrogens also activate GPER-1 a relevant observation since GPER-1 is involved in several physiopathological disorders and especially in estrogen-dependent diseases such as breast cancer.The first estrogen receptors discovered were the classical ERα and ERβ, but from an evolutionary point of view G protein-coupled receptors trace their origins in history to over a billion years ago suggesting that estrogen receptors like GPER-1 may have been the targets of choice for ancient phytoestrogens and/or estrogens.This review provides a comprehensive and systematic literature search on phytoestrogens and its relationship with classical estrogen receptors and GPER-1 including its role in breast cancer, an issue still under discussion.