Androgen stimulates endothelial cell proliferation via an androgen receptor/VEGF/cyclin A-mediated mechanism

Menopause-related changes in vascular signaling by sex hormones

Cardiovascular disease (CVD), such as hypertension and coronary artery disease, involves pathological changes in vascular signaling, function, and structure. Vascular signaling is regulated by multiple intrinsic and extrinsic factors that influence endothelial cells, vascular smooth muscle, and extracellular matrix. Vascular function is also influenced by environmental factors including diet, exercise, and stress, as well as genetic background, sex differences, and age. CVD is more common in adult men and postmenopausal women than in premenopausal women. Specifically, women during menopausal transition, with declining ovarian function and production of estrogen (E2) and progesterone, show marked increase in the incidence of CVD and associated vascular dysfunction. Mechanistic research suggests that E2 and E2 receptor signaling have beneficial effects on vascular function including vasodilation, decreased blood pressure, and cardiovascular protection. Also, the tangible benefits of E2 supplementation in improving menopausal symptoms have prompted clinical trials of menopausal hormone therapy (MHT) in CVD, but the results have been inconsistent. The inadequate benefits of MHT in CVD could be attributed to the E2 type, dose, formulation, route, timing, and duration as well as menopausal changes in E2/E2 receptor vascular signaling. Other factors that could affect the responsiveness to MHT are the integrated hormonal milieu including gonadotropins, progesterone, and testosterone, vascular health status, preexisting cardiovascular conditions, and menopause-related dysfunction in the renal, gastrointestinal, endocrine, immune, and nervous systems. Further analysis of these factors should enhance our understanding of menopause-related changes in vascular signaling by sex hormones and provide better guidance for management of CVD in postmenopausal women. SIGNIFICANCE STATEMENT: Cardiovascular disease is more common in adult men and postmenopausal women than premenopausal women. Earlier observations of vascular benefits of menopausal hormone therapy did not materialize in randomized clinical trials. Further examination of the cardiovascular effects of sex hormones in different formulations and regimens, and the menopausal changes in vascular signaling would help to adjust the menopausal hormone therapy protocols in order to enhance their effectiveness in reducing the risk and the management of cardiovascular disease in postmenopausal women.

Androgenic Anabolic Steroids Cause Thiol Imbalance in the Vascular Endothelial Cells

BACKGROUND

Androgenic anabolic steroids (AASs) are synthetic drugs structurally related to testosterone, with the ability to bind to androgen receptors. Their uncontrolled use by professional and recreational sportspeople is a widespread problem. AAS abuse is correlated with severe damage to the cardiovascular system, including changes in homeostasis and coagulation disorders. AASs alter vascular function by blocking nitric oxide (NO)-mediated dilation, impairing endothelial growth and by potentiating vasoconstrictor signals.

METHODS

This paper demonstrated that long-term use of AASs (nandrolone and boldenone), negatively affects the basic cell functions of vascular endothelial cells. The susceptibility of endothelial cells to AASs depends on the expression of androgen receptors, although cells without androgen receptors can also be affected by high doses of AASs to a limited extent. Seven-day incubation with AASs diminishes endothelial cell proliferation and migration (determined by transwell and scratch migration assay) and monolayer formation (using transendothelial electrical resistance assay).

RESULTS

Disturbances in cell function were accompanied by downregulation of peroxiredoxins (PRDX1 and PRDX2), involved in maintaining the thiol-disulphide balance. In addition, AASs increased oxidation of the non-enzymatic thiol buffer, glutathione (GSH), reduced secretion of thiol oxidoreductase protein disulphide isomerase (PDI) from endothelial cells and affected the thiol pattern of PDI.

CONCLUSIONS

These changes may be related to a thiol-disulfide imbalance and vascular endothelium dysfunction, that are often correlated with abnormal platelet aggregation, inflammation, increased vascular permeability, and vascular smooth muscle cell proliferation-all of which are observed in athletes who abuse AASs.

The role of androgens in migraine pathophysiology

Migraine affects ∼12 % of the worldwide population and is more prevalent in females, which suggests a role of sex hormones in migraine pathophysiology. Most studies have focused on estrogen and progesterone, and the involvement of androgens has been less studied. However, due to the recent advances in androgen interventions, which could advance new androgen-based migraine treatments, it is critical to better understand the role of androgens in migraine. Testosterone, the most studied androgen, was found to have an antinociceptive effect in various animal and human pain studies. Thus, it could also have a protective effect related to lower migraine severity and prevalence. In this review, we discuss studies examining the role of androgens on migraine-related symptoms in migraine animal models. Additionally, we summarize the results of human studies comparing androgen levels between patients with migraine and healthy controls, studies assessing the relationships between androgen levels and migraine severity, and intervention studies examining the impact of testosterone treatment on migraine severity. Many of the studies have limitations, however, the results suggest that androgens may have a minor effect on migraine. Still, it is possible that androgens are involved in migraine pathophysiology in a sub-group of patients such as in adolescents or postmenopausal women. We discuss potential mechanisms in which testosterone, as the main androgen tested, can impact migraine. These mechanisms range from the cellular level to systems and behavior and include the effect of testosterone on sensory neurons, the immune and vascular systems, the stress response, brain function, and mood. Lastly, we suggest future directions to advance this line of research.

Novel Plasma Membrane Androgen Receptor SLC39A9 Mediates Ovulatory Changes in Cells of the Monkey Ovarian Follicle

Follicular androgens are important for successful ovulation and fertilization. The classical nuclear androgen receptor (AR) is a transcription factor expressed in the cells of the ovarian follicle. Androgen actions can also occur via membrane androgen receptor SLC39A9. Studies in fish ovary demonstrated that androgens bind to SLC39A9 and increase intracellular zinc to regulate ovarian cell function. To determine if SLC39A9 is expressed and functional in the key cell types of the mammalian ovulatory follicle, adult female cynomolgus macaques underwent ovarian stimulation. Ovaries or ovarian follicular aspirates were harvested at 0, 12, 24, and 36 hours after human chorionic gonadotropin (hCG). SLC39A9 and AR mRNA and protein were present in granulosa, theca, and vascular endothelial cells across the entire 40-hour ovulatory window. Testosterone, bovine serum albumin-conjugated testosterone (BSA-T), and androstenedione stimulated zinc influx in granulosa, theca, and vascular endothelial cells. The SLC39A9-selective agonist (-)-epicatechin also stimulated zinc influx in vascular endothelial cells. Taken together, these data support the conclusion that SLC39A9 activation via androgen induces zinc influx in key ovarian cells. Testosterone, BSA-T, and androstenedione each increased proliferation in vascular endothelial cells, indicating the potential involvement of SLC39A9 in ovulatory angiogenesis. Vascular endothelial cell migration also increased after treatment with testosterone, but not after treatment with BSA-T or androstenedione, suggesting that androgens stimulate vascular endothelial cell migration through nuclear AR but not SLC39A9. The presence of SLC39A9 receptors and SLC39A9 activation by follicular androstenedione concentrations suggests that androgen activation of ovarian SLC39A9 may regulate ovulatory changes in the mammalian follicle.

Dihydrotestosterone Augments the Angiogenic and Migratory Potential of Human Endothelial Progenitor Cells by an Androgen Receptor-Dependent Mechanism

Endothelial progenitor cells (EPCs) play a critical role in cardiovascular regeneration. Enhancement of their native properties would be highly beneficial to ensuring the proper functioning of the cardiovascular system. As androgens have a positive effect on the cardiovascular system, we hypothesized that dihydrotestosterone (DHT) could also influence EPC-mediated repair processes. To evaluate this hypothesis, we investigated the effects of DHT on cultured human EPCs' proliferation, viability, morphology, migration, angiogenesis, gene and protein expression, and ability to integrate into cardiac tissue. The results showed that DHT at different concentrations had no cytotoxic effect on EPCs, significantly enhanced the cell proliferation and viability and induces fast, androgen-receptor-dependent formation of capillary-like structures. DHT treatment of EPCs regulated gene expression of androgen receptors and the genes and proteins involved in cell migration and angiogenesis. Importantly, DHT stimulation promoted EPC migration and the cells' ability to adhere and integrate into murine cardiac slices, suggesting it has a role in promoting tissue regeneration. Mass spectrometry analysis further highlighted the impact of DHT on EPCs' functioning. In conclusion, DHT increases the proliferation, migration, and androgen-receptor-dependent angiogenesis of EPCs; enhances the cells' secretion of key factors involved in angiogenesis; and significantly potentiates cellular integration into heart tissue. The data offer support for potential therapeutic applications of DHT in cardiovascular regeneration and repair processes.

Targeting androgen receptor (AR) with a synthetic peptide increases apoptosis in triple negative breast cancer and AR-expressing prostate cancer cell lines

BACKGROUND

The androgen receptor (AR) has been studied as an approach to cancer therapy.

AIMS

We used human breast cancer-derived cells with high, low, and very low expression levels of AR, in addition to prostate cancer-derived LNCaP and DU-145 cells as a positive and negative controls to examine apoptosis caused by a synthetic peptide that targets ARs.

METHODS AND RESULTS

The peptide was produced to inhibit AR transactivation in breast cancer cell lines. We then measured cell viability, caspase-3 activity, and the ratio of Bax/Bcl-2. The findings indicated that the peptide (100-500 nM) in the presence of dihydrotestosterone (DHT) reduced cell growth in cells with high and low expression level of AR (p < .001), but not in cells with very low levels of AR. Treatment with 100-500 nM of peptide activated caspase-3 and increased the ratio of Bax/Bcl-2 in cells with high and low expression levels of AR. Also, increasing concentrations of the peptide (100-500 nM) reduced BrdU incorporation in the presence of DHT and promoted apoptosis in cells with high and low expression levels of AR (p < .001).

CONCLUSION

The findings indicate the peptide significantly increased apoptosis in cancer cells.

Disruption of Vitamin D Signaling Impairs Adaptation of Cerebrocortical Microcirculation to Carotid Artery Occlusion in Hyperandrogenic Female Mice

Vitamin D deficiency contributes to the pathogenesis of age-related cerebrovascular diseases, including ischemic stroke. Sex hormonal status may also influence the prevalence of these disorders, indicated by a heightened vulnerability among postmenopausal and hyperandrogenic women. To investigate the potential interaction between sex steroids and disrupted vitamin D signaling in the cerebral microcirculation, we examined the cerebrovascular adaptation to unilateral carotid artery occlusion (CAO) in intact, ovariectomized, and hyperandrogenic female mice with normal or functionally inactive vitamin D receptor (VDR). We also analyzed the morphology of leptomeningeal anastomoses, which play a significant role in the compensation. Ablation of VDR by itself did not impact the cerebrocortical adaptation to CAO despite the reduced number of pial collaterals. While ovariectomy did not undermine compensatory mechanisms following CAO, androgen excess combined with VDR inactivity resulted in prolonged hypoperfusion in the cerebral cortex ipsilateral to the occlusion. These findings suggest that the cerebrovascular consequences of disrupted VDR signaling are less pronounced in females, providing a level of protection even after ovariectomy. Conversely, even short-term androgen excess with lacking VDR signaling may lead to unfavorable outcomes of ischemic stroke, highlighting the complex interplay between sex steroids and vitamin D in terms of cerebrovascular diseases.

Androgen receptor (CAG)n repeat polymorphism contributes to risk of sudden cardiac death originated from coronary artery disease with sex discrepancy

Sudden cardiac death (SCD) is the leading cause of natural death worldwide which is responsible for almost half of all heart disease deaths, making it a substantial public health problem. Previous epidemiological studies from different countries have demonstrated the significant SCD incident difference rate between males and females. Besides environmental and social effects, differential genetic architecture also underlines the SCD incidence discrepancy. To this end, the functional (CAG)_n repeat polymorphism within Androgen Receptor (AR) gene was analyzed to evaluate its associations with SCD originated from coronary artery disease (SCD-CAD) susceptibility in Chinese populations using 182 SCD-CAD cases and 564 healthy controls. At allelic level, the (CAG)₂₆ allele conferred a lower SCD-CAD risk in males (adjusted odds ratio [OR] = 0.428; 95% confidence interval [CI] = 0.254, 0.915; P = 0.023). On the contrary, the (CAG)₂₆ allele was reversely associated with a higher SCD-CAD risk in females (OR = 2.581; 95% CI = 0.944, 7.056; P = 0.057). Further cutoff strategy analysis revealed that those male subjects carrying shorter allele (≤26 repeats) had significantly lower SCD-CAD risk (OR = 0.343; 95% CI = 0.221, 0.531; P = 8.1653e^-7). Additionally, an allele-dependent SCD risk tendency was observed in male subjects. Specifically, compared with males carrying allele longer than 26 repeats, the SCD-CAD risk (OR value) for male subjects carrying shorter alleles (from 25 to 21) gradually increased from 0.437 to 0.533, indicating the (CAG)₂₆ allele of the repeat polymorphism may be the watershed in male SCD etiology. Lastly, the length variations associated with multiple phenotypes were also summarized. Collectively, our results revealed for the first time that the (CAG)_n repeat polymorphism within the AR gene was associated with SCD-CAD risk in Chinese populations with sex discrepancy, proposing a new candidate genetic marker for molecular diagnosis of SCD-CAD. Furthermore, a sex-dependent SCD-CAD risk stratification and prevention approach was encouraged. Further studies with more female samples were warranted to validate our findings.

Sex-related external factors influence pulmonary vascular angiogenesis in a sex-dependent manner

Bronchopulmonary dysplasia (BPD) is a disease with a significant sexual dimorphism where males have a disadvantage compared with their female counterparts. Although mechanisms behind this sexual dimorphism are poorly understood, sex differences in angiogenesis have been identified as one possible source of the male disadvantage in BPD. Pulmonary angiogenesis was assessed in vitro using a bead sprouting assay with pooled male or female human pulmonary microvascular endothelial cells (HPMECs, 18-19 wk gestation, canalicular stage of human lung development) in standard (sex-hormone containing) and hormone-stripped medium. We identified sex-specific phenotypes in angiogenesis where male HPMECs produce fewer but longer sprouts compared with female HPMECs. The presence of sex hormones from standard culture medium modifies the male HPMEC phenotype with shorter and fewer sprouts but does not influence the female phenotype. Using a conditioned medium model, we further characterized the influence of the sex-specific secretome. Male and female HPMECs secrete factors that increase the maximum length of sprouts in female, but not male HPMECs. The presence of sex hormones abolishes this response. The male HPMEC secretome inhibits angiogenic sprouting in male HPMECs in the absence of sex hormones. Taken together, these results demonstrate that the pulmonary endothelial cell phenotypes are influenced by sex hormones and sex-specific secreted factors in a sex-dependent manner.NEW & NOTEWORTHY We identified a sex-specific phenotype wherein male HPMECs produce fewer but longer sprouts than females. Surprisingly, the presence of sex hormones only modifies the male phenotype, resulting in shorter and even fewer sprouts. Furthermore, we found the sex-specific secretome has a sex-dependent influence on angiogenesis that is also sex-hormone sensitive. These new and surprising findings point to the unappreciated role of sex and sex-related exogenous factors in early developmental angiogenesis.

Evaluation of the Interaction of Sex Hormones and Cardiovascular Function and Health

Purpose of Review

Sex hormones drive development and function of reproductive organs or the development of secondary sex characteristics but their effects on the cardiovascular system are poorly understood. In this review, we identify the gaps in our understanding of the interaction between sex hormones and the cardiovascular system.

Recent Findings

Studies are progressively elucidating molecular functions of sex hormones in specific cell types in parallel with the initiation of crucial large randomized controlled trials aimed at improving therapies for cardiovascular diseases (CVDs) associated with aberrant levels of sex hormones.

Summary

In contrast with historical assumptions, we now understand that men and women show different symptoms and progression of CVDs. Abnormal levels of sex hormones pose an independent risk for CVD, which is apparent in conditions like Klinefelter syndrome, androgen insensitivity syndrome, and menopause. Moreover, sex hormone–based therapies remain understudied and may not be beneficial for cardiovascular health.

Sexual Dimorphism in Small-intestinal Neuroendocrine Tumors: Lower Prevalence of Mesenteric Disease in Premenopausal Women

CONTEXT

Small-intestinal neuroendocrine tumors (SI-NETs) have a modest but significantly higher prevalence and worse prognosis in male patients.

OBJECTIVE

This work aims to increase understanding of this sexual dimorphism in SI-NETs.

PATIENTS AND METHODS

Retrospectively, SI-NET patients treated in a single tertiary center were included and analyzed for disease characteristics. Estrogen receptor 1 (ESR1) and 2 (ESR2), progesterone receptor (PGR), and androgen receptor (AR) messenger RNA (mRNA) expression was assessed in primary tumors and healthy intestine. Estrogen receptor alpha (ERα) and AR protein expression were analyzed by immunohistochemistry in primary tumors and mesenteric metastases.

RESULTS

Of the 559 patients, 47% were female. Mesenteric metastasis/fibrosis was more prevalent in men (71% / 46%) than women (58% / 37%; P = 0.001 and P = 0.027, respectively). In women, prevalence of mesenteric metastases increased gradually with age from 41.1% in women <50 years to 71.7% in women >70 years. Increased expression of ESR1 and AR mRNA was observed in primary tumors compared to healthy intestine (both P < 0.001). ERα staining was observed in tumor cells and stroma with a strong correlation between tumor cells of primary tumors and mesenteric metastases (rho = 0.831, P = 0.02), but not in stroma (rho = -0.037, P = 0.91). AR expression was only found in stroma.

CONCLUSION

Sexual dimorphism in SI-NETs was most pronounced in mesenteric disease, and the risk of mesenteric metastasis in women increased around menopause. The combination of increased ERα and AR expression in the SI-NET microenvironment suggests a modulating role of sex steroids in the development of the characteristic SI-NET mesenteric metastasis and associated fibrosis.

Androgens promote vascular endothelial cell proliferation through activation of a ZIP9-dependent inhibitory G protein/PI3K-Akt/Erk/cyclin D1 pathway

While androgens have been reported to mediate cardiovascular endothelial cell proliferation, the potential involvement of membrane androgen receptors (mAR) has not been examined. Here we show ZIP9, a recently characterized mAR, mediates androgen-induced early proliferative events in human umbilical vein endothelial cells (HUVECs). Androgen treatment significantly increased cyclin D1 nuclear localization and proliferation, which were blocked by transfection with siRNA targeting ZIP9 but not the nuclear AR. Testosterone rapidly activated inhibitory G protein signaling, Erk, and Akt, and inhibition of these signaling members abrogated the ZIP9-mediated cyclin D1 and proliferative responses. Erk and Akt modulated cyclin D1 nuclear localization by upregulation of cyclin D1 mRNA and inhibition of GSK-3β activity, respectively. This is the first study to demonstrate a role for ZIP9 in HUVEC proliferation and indicates ZIP9 is a physiologically-relevant androgen receptor in the cardiovascular system that merits further study as a potential therapeutic target for treating cardiovascular disease.

Fetoplacental vasculature as a model to study human cardiovascular endocrine disruption

Increasing evidence has associated the exposure of endocrine-disrupting chemicals (EDCs) with the cardiovascular (CV) system. This exposure is particularly problematic in a sensitive window of development, pregnancy. Pregnancy exposome can affect the overall health of the pregnancy by dramatic changes in vascular physiology and endocrine activity, increasing maternal susceptibility. Moreover, fetoplacental vascular function is generally altered, increasing the risk of developing pregnancy complications (including cardiovascular diseases, CVD) and predisposing the foetus to adverse health risks later in life. Thus, our review summarizes the existing literature on exposures to EDCs during pregnancy and adverse maternal health outcomes, focusing on the human placenta, vein, and umbilical artery associated with pregnancy complications. The purpose of this review is to highlight the role of fetoplacental vasculature as a model for the study of human cardiovascular endocrine disruption. Therefore, we emphasize that the placenta, together with the umbilical arteries and veins, allows a better characterization of the pregnant woman's exposome. Consequently, it contributes to the protection of the mother and foetus against CV disorders in life.

Dehydroepiandrosterone (DHEA) role in enhancement and maintenance of implantation (DREAM): randomised double-blind placebo-controlled trial-study protocol

INTRODUCTION

Dehydroepiandrosterone (DHEA) is an important precursor of androgen and has been studied and researched extensively for improving the various outcome measures of ovarian stimulation in women with advanced age or poor ovarian response. Androgens also play an important role in the enhancement of endometrial and decidual function by regulating both the transcriptome and secretome of the endometrial stromal cells and have a positive effect on various factors like insulin-like growth factor binding protein 1, homeobox genes (HOXA10, HOXA11), secreted phosphoprotein 1, prolactin which are necessary for implantation. It is well-known that the circulating 'precursor pool' of DHEA declines with age more so in poor ovarian reserve patients and exogenous supplementation may be beneficial in such cases. This double-blinded randomised controlled trial (RCT) aims to test the hypothesis whether transient targeted supplementation of DHEA as an adjuvant to progesterone in frozen embryo transfer (FET) cycles, for women with low serum testosterone, helps in improving live birth rate.

METHODS AND ANALYSIS

This study is planned as a double-blinded, placebo-controlled randomised trial and the sample size, calculated for the primary outcome measure-live birth rate, is 140. All participants will be having a flexible antagonist protocol for controlled ovarian stimulation and an elective freeze-all policy for the embryos as per the hospital protocol after written informed consent. For FET, the endometrium will be prepared by hormone replacement treatment protocol. During the FET cycle, the intervention group will be receiving DHEA 25 mg two times a day for 15 days from the day of starting progesterone supplementation and the control group will be receiving a placebo.

ETHICS AND DISSEMINATION

The approval of the study was granted by the Clinical Trials Registry-India and the Institutional Ethical Committee of CRAFT Hospital and Research Center. All participants will provide written informed consent before being randomised into allocated treatment groups. The results will be disseminated to doctors and patients through conference presentations, peer-reviewed publications, social media and patient information booklets.

TRIAL REGISTRATION NUMBERS

CTRI/2020/06/025918; ECR/1044/Inst/KL/2018.

The Role of Androgen Receptor in Cross Talk Between Stromal Cells and Prostate Cancer Epithelial Cells

Prostate cancer (PCa) lists as the second most lethal cancer for men in western countries, and androgen receptor (AR) plays a central role in its initiation and progression, which prompts the development of androgen deprivation therapy (ADT) as the standard treatment. Prostate tumor microenvironment, consisting of stromal cells and extracellular matrix (ECM), has dynamic interactions with PCa epithelial cells and affects their growth and invasiveness. Studies have shown that both genomic and non-genomic AR signaling pathways are involved in the biological regulation of PCa epithelial cells. In addition, AR signaling in prostate stroma is also involved in PCa carcinogenesis and progression. Loss of AR in PCa stroma is clinically observed as PCa progresses to advanced stage. Especially, downregulation of AR in stromal fibroblasts dysregulates the expression levels of ECM proteins, thus creating a suitable environment for PCa cells to metastasize. Importantly, ADT treatment enhances this reciprocal interaction and predisposes stromal cells to promote cell invasion of PCa cells. During this process, AR in PCa epithelium actively responds to various stimuli derived from the surrounding stromal cells and undergoes enhanced degradation while elevating the expression of certain genes such as MMP9 responsible for cell invasion. AR reduction in epithelial cells also accelerates these cells to differentiate into cancer stem-like cells and neuroendocrine cells, which are AR-negative PCa cells and inherently resistant to ADT treatments. Overall, understanding of the cross talk between tumor microenvironment and PCa at the molecular level may assist the development of novel therapeutic strategies against this disease. This review will provide a snapshot of AR's action when the interaction of stromal cells and PCa cells occurs.

11-Ketotestosterone is a major androgen produced in porcine adrenal glands and testes

Porcine steroid hormone profiles have some unique characteristics. We previously studied human and murine steroidogenesis using steroidogenic cells-derived from mesenchymal stem cells (MSCs). To investigate porcine steroidogenesis, we induced steroidogenic cells from porcine subcutaneous preadipocytes (PSPA cells), which originate from MSCs. Using cAMP, adenovirus-mediated introduction of steroidogenic factor-1 (SF-1)/adrenal 4-binding protein (Ad4BP) induced the differentiation of PSPA cells into sex steroid-producing cells. Introducing SF-1/Ad4BP also induced the aldo-keto reductase 1C1 (AKR1C1) gene. Porcine AKR1C1 had 17β-hydroxysteroid dehydrogenase activity, which converts androstenedione and 11-ketoandrostenedione into testosterone (T) and 11-ketotestosteorne (11KT). Furthermore, differentiated cells expressed hydroxysteroid 11β-dehydrogenase 2 (HSD11B2) and produced 11KT. HSD11B2 was expressed in testicular Leydig cells and the adrenal cortex. 11KT was present in the plasma of both immature male and female pigs, with slightly higher levels in the male pigs. T levels were much higher in the male pigs. It is noteworthy that in the female pigs, the 11KT levels were >10-fold higher than the T levels. However, castration altered the 11KT and T plasma profiles in the male pigs to near those of the females. 11KT induced endothelial nitric oxide synthase (eNOS) in porcine vascular endothelial cells. These results indicate that 11KT is produced in porcine adrenal glands and testes, and may regulate cardiovascular functions through eNOS expression.

Quantitative evaluations of vortex vein ampullae by adjusted 3D reverse projection model of ultra-widefield fundus images

The purpose of this study was to determine the number and location of vortex vein ampullae (VVA) in normal eyes. This was an observational retrospective study. Montage images of one on-axis and two off-axis ultra-widefield images of 74 healthy eyes were enhanced, and reverse projected onto a 3D model eye. The number and distance between the optic disc to each VVA in the four sectors were compared. The significance of correlations between these values and age, sex, visual acuity, refractive error, and axial length was determined. The mean number of VVA was 8.10/eye with 1.84, 2.12, 2.19 and 1.95 in upper lateral, lower lateral, upper nasal, and lower nasal sectors, respectively. The mean number of VVA/eye was significantly greater in men at 8.43 than women at 7.76 (P = 0.025). The mean distance between the optic disc and VVA was 14.15 mm, and it was 14.04, 15.55, 13.29 and 13.66 mm in the upper lateral, lower lateral, upper nasal and lower nasal sectors, respectively (all P < 0.05). The number and location of VVA can be obtained non-invasively, and the number was significantly higher in men than women. This technique can be used to determine whether these values are altered in a retinochoroidal disease.

The role of androgen receptors in vascular and cell proliferation of the prostate adenocarcinomas

Prostate adenocarcinoma (PA) is by incidence and prognosis a unique model for investigating the biomolecular mechanisms involved in tumor progression. In this study, we analyzed the immunoexpression of androgen receptor (AR), cluster of differentiation 105 (CD105) and Ki67 for 61 cases of PA, in relation to the main clinicopathological parameters of the lesions. The AR scores, CD105 microvessel density (MVD) and Ki67 proliferation index (PI) were significantly higher in patients with serum prostate-specific antigen (PSA) above 20 ng/mL, in ductal, colloid and sarcomatoid types of PA, in growth patterns 4–5 or mixed, respectively in the case of high-grade advanced stage tumors, with perineural and vascular invasion, as well as in groups with a reserved prognosis. The results obtained, reflected in the positive linear correlation of AR, CD105 and Ki67 expression, indicate synchronous endocrine, angiogenic and proliferative mechanisms involved in tumor progression, which can be used to optimize the targeted tumor therapy.

Endocrine Challenges in Patients with Continuous-Flow Left Ventricular Assist Devices

Heart failure (HF) remains a leading cause of morbidity, hospitalization, and mortality worldwide. Advancement of mechanical circulatory support technology has led to the use of continuous-flow left ventricular assist devices (LVADs), reducing hospitalizations, and improving quality of life and outcomes in advanced HF. Recent studies have highlighted how metabolic and endocrine dysfunction may be a consequence of, or associated with, HF, and may represent a novel (still neglected) therapeutic target in the treatment of HF. On the other hand, it is not clear whether LVAD support, may impact the outcome by also improving organ perfusion as well as improving the neuro-hormonal state of the patients, reducing the endocrine dysfunction. Moreover, endocrine function is likely a major determinant of human homeostasis, and is a key issue in the recovery from critical illness. Care of the endocrine function may contribute to improving cardiac contractility, immune function, as well as infection control, and rehabilitation during and after a LVAD placement. In this review, data on endocrine challenges in patients carrying an LVAD are gathered to highlight pathophysiological states relevant to this setting of patients, and to summarize the current therapeutic suggestions in the treatment of thyroid dysfunction, and vitamin D, erythropoietin and testosterone administration.

Low Serum-Free Testosterone Concentration in Chinese Male Patients with Uncomplicated Acute Type B Aortic Dissection

OBJECTIVE

Although aortic dissection occurs predominantly in men, its association with androgens is unknown. The aim of this study was to evaluate the androgen levels in Chinese male patients with uncomplicated, acute type B aortic dissection.

STUDY DESIGN

Cross-sectional study.

MATERIALS AND METHODS

A total of 192 age-matched male patients with uncomplicated, acute type B aortic dissection or essential hypertension were recruited between 2016 and 2018. The demographic and clinical data were analyzed.

RESULTS

Male patients with uncomplicated, acute type B aortic dissection had lower serum total testosterone and free testosterone than male patients with essential hypertension (7.6 ± 3.7 nmol/L vs. 10.9 ± 3.8 nmol/L, P < 0.001; 36.0 ± 19.8 pmol/L vs. 56.4 ± 19.2 pmol/L, P < 0.001). Lower free testosterone level was significantly associated with uncomplicated, acute type B aortic dissection (univariate odds ratio 0.948, P < 0.001; multivariate odds ratio = 0.966, P = 0.002). No statistical difference was observed for free testosterone between younger patient groups (aged < 51 years; aged 51-60 years) and older patient groups (aged 61-70 years; aged >70 years) with uncomplicated, acute type B aortic dissection (33.7 ± 19.8 pmol/L vs. 38.5 ± 19.8 pmol/L, P = 0.239).

CONCLUSIONS

Lower free testosterone was independently associated with uncomplicated, acute type B aortic dissection in the Chinese male population with hypertension. Additional studies are needed to clarify whether earlier onset in Chinese patients with aortic dissection is associated with androgen deficiency.

Androgens Stimulate EPC-Mediated Neovascularization and Are Associated with Increased Coronary Collateralization

Endothelial progenitor cells (EPCs) play a key role in neovascularization and have been linked to improved cardiovascular outcomes. Although there is a well-established inverse relationship between androgen levels and cardiovascular mortality in men, the role of androgens in EPC function is not fully understood. In this study, we investigated the effects of androgens on 2 subpopulations of EPCs, early EPCs (EEPCs) and late outgrowth EPCs (OECs), and their relationships with coronary collateralization. Early EPCs and OECs were isolated from the peripheral blood of young healthy men and treated with dihydrotestosterone (DHT) with or without androgen receptor (AR) antagonist, hydroxyflutamide, in vitro. Dihydrotestosterone treatment enhanced AR-mediated proliferation, migration, and tubulogenesis of EEPCs and OECs in a dose-dependent manner. Furthermore, DHT augmented EPC sensitivity to extracellular stimulation by vascular endothelial growth factor (VEGF) via increased surface VEGF receptor expression and AKT activation. In vivo, xenotransplantation of DHT pretreated human EPCs augmented blood flow recovery and angiogenesis in BALB/c nude male mice, compared to mice receiving untreated EPCs, following hindlimb ischemia. In particular, DHT pretreated human OECs exhibited higher reparative potential than EEPCs in augmenting postischemic blood flow recovery in mice. Furthermore, whole blood was collected from the coronary sinus of men with single vessel coronary artery disease (CAD) who underwent elective percutaneous intervention (n = 23). Coronary collateralization was assessed using the collateral flow index. Serum testosterone and EPC levels were measured. In men with CAD, circulating testosterone was positively associated with the extent of coronary collateralization and the levels of OECs. In conclusion, androgens enhance EPC function and promote neovascularization after ischemia in mice and are associated with coronary collateralization in men.

Androgen receptor activation reduces the endothelial cell proliferation through activating the cSrc/AKT/p38/ERK/NFκB-mediated pathway

The effect of androgen on angiogenesis has been documented. However, its underlying molecular mechanisms have not been well illustrated. Here, we show that treatment with an androgen receptor (AR) agonist, metribolone (R1881; 0.05-5 nM), or dihydrotestosterone (DHT; 0.5-2 nM), concentration- and time-dependently inhibited proliferation in human umbilical venous endothelial cells (HUVEC). This inhibitory effect was confirmed in human microvascular endothelial cells (HMEC-1). Flow cytometric analysis demonstrated that R1881 induced G0/G1 phase cell cycle arrest in HUVEC. Blockade of the AR activity by pre-treatment with an AR antagonist, hydroxyflutamide (HF), or knockdown of AR expression using the shRNA technique abolished the R1881-induced HUVEC proliferation inhibition, suggesting that AR activation can inhibit endothelial cell proliferation. We further investigated the signaling pathway contributing to the proliferation inhibition induced by AR activation. Our data suggest that R1881 reduced the proliferation rate of HUVEC through activating the AR/cSrc/AKT/p38/ERK/NFκB pathway, subsequently up-regulating p53 expression, which in turn increased the levels of p21 and p27 protein, hence decreasing the activities of cyclin-dependent kinase 2 (CDK2) and CDK4, and finally reduced the cell proliferation rate. An extra-nuclear pathway involved in the proliferation inhibition induced by AR activation in vascular endothelial cells was confirmed by showing that membrane-impermeable testosterone-bovine serum albumin (BSA) treatment significantly increased the levels of p53, p27 and p21 protein and reduced cell proliferation. These data highlight the underlying molecular mechanisms by which AR activation induced proliferation inhibition in vascular endothelial cells.

Structural and functional abnormalities of penile cavernous endothelial cells result in erectile dysfunction at experimental autoimmune prostatitis rat

Background

There is growing recognition of the association of CP/CPPS accompany with ED. However, the specific mechanism of action remains unclear. The aim of this study was to investigate structural and functional abnormalities of cavernous endothelial cells in EAP rat, which may result in the ED.

Methods

we use rat prostate protein extract supplemented with immunoadjuvant to induce EAP rat, ICP and MAP were measured and inflammatory factor infiltration, Akt, eNOS, AR, nNOS and iNOS in the corpus cavernosum were tested. Subsequently, the normal rat and EAP rat cavernosum endothelial cells were purified by MACS, and the metabolism, oxidative stress, MMP, Akt, eNOS, AR and iNOS were evaluated.

Results

The EAP rat model was successfully constructed. The ratio of max ICP/MAP in EAP rat was significantly lower and TNF-α infiltration in corpus cavernosum was significantly higher than normal rats. Besides, Akt, eNOS and AR were decreased, iNOS was significantly increased. The growth and metabolism of endothelial cells in the EAP rats corpus cavernosum decreased and inflammatory factor mRNA was increased and intracellular oxidative stress was also increased significantly. The MMP of EAP rats cavernosum endothelial cells decreased and the expression of Akt, eNOS and AR were also significantly decreased, iNOS was significantly increased.

Conclusion

The prostate suffer local inflammatory infiltrate and promotes cytokines infiltrated into corpus cavernosum caused the oxidative stress increases and the metabolism or MMP decreases. In addition, AR, Akt and eNOS expression and phosphorylation are also reduced, thereby inhibiting the diastolic function of the corpus cavernosum, resulting in decreased erectile function.

Cadmium exposure alters steroid receptors and proinflammatory cytokine levels in endothelial cells in vitro: a potential mechanism of endocrine disruptor atherogenic effect

BACKGROUND

Cadmium (Cd) is a widespread environmental pollutant that causes alterations in human health acting as endocrine disruptor. Recent data suggest that cardiovascular system might be a contamination target tissue, since Cd is found in atheromatic plaques. Thus, the purpose of this study was to evaluate the consequence of Cd exposure of endothelial cells in vitro to evaluate detrimental effect in vascular system by a potential sex-steroid hormone receptor-dependent mechanism(s).

METHODS

To this aim, Human Umbilical Vein Endothelial Cells (HUVECs) were cultured and exposed to several concentrations of cadmium chloride (CdCl₂) for different interval times.

RESULTS

CdCl₂ exposure of HUVECs induced a significant increase of ERβ and Cyp19a1 at both mRNA and protein levels, while a drastic dose-dependent decrease of AR expression level was observed after 24 h of exposure. On the contrary, an increase of PhAR^ser308 as well as a reduction of PhGSK-3β^ser9 and PhAKT^ser473 was detected after 1 h treatment. This effect was consistently reduced by GSK inhibition. Furthermore, CdCl₂ abolished DHT-induced cell proliferation in HUVECs suggesting an antagonist-like effect of Cd on AR-mediated signaling. Remarkable, after 6 h CdCl₂-treatment, a relevant increase in TNF-α, IL-6 and IL-8 mRNA was observed and this effect was blocked by the presence of an ERβ-selective antagonist. Moreover, Cd-induced TxR1 overexpression, likely, correlated with the activation of p38 MAPK/NF-κB pathway.

CONCLUSION

In conclusion, our study demonstrates for the first time that Cd alters sex-steroid hormone receptors level and activity likely affecting intracellular signaling linked to a proinflammatory state in endothelial cells. This alteration might possibly lead to endothelial cell injury and vascular dysfunction and could be a mechanism of gender-specific atherogenic damages induced by endocrine disruptors and, thus, induce atherogenic events with increased risk of cardiovascular diseases in individuals exposed to this endocrine disruptor.

Testosterone induced downregulation of migration and proliferation in human Umbilical Vein Endothelial Cells by Androgen Receptor dependent and independent mechanisms

Recent research has emphasized the potential unfavorable effects of declining testosterone (T) levels in men and the putative beneficial effect of androgen therapy in select women. Some controversy surrounding the mechanism of action and the effects of T on endothelium remains. In this study, we evaluated the mechanism of T action on pooled primary Human Umbilical Vein Endothelial Cells (HUVEC) of mixed gender by focusing on two important processes, proliferation and migration. In our in vitro model system, we found that only the supra-physiological dose of T affected these two processes irrespective of the ratio of male to female cells in the pools. At a concentration of 1 μM, T downregulated the proliferation of HUVEC by inducing arrest in the G1 cell cycle phase in an Androgen Receptor (AR)-independent manner. We show that treatment with 1 μM T also induced downregulation of HUVEC migration. This process was AR-dependent and was associated with persistent phosphorylation of ezrin, radixin and moesin. Regardless of the mechanism of action, the treatment of HUVEC with both supra- and physiological doses of T was associated with posttranscriptional stabilization of the AR upon ligand binding.

Role of androgens in cardiovascular pathology

Cardiovascular effects of android hormones in normal and pathological conditions can lead to either positive or negative effects. The reason for this variation is unknown, but may be influenced by gender-specific effects of androids, heterogeneity of the vascular endothelium, differential expression of the androgen receptor in endothelial cells (ECs) and route of androgen administration. Generally, androgenic hormones are beneficial for ECs because these hormones induce nitric oxide production, proliferation, motility, and growth of ECs and inhibit inflammatory activation and induction of procoagulant, and adhesive properties in ECs. This indeed prevents endothelial dysfunction, an essential initial step in the development of vascular pathologies, including atherosclerosis. However, androgens can also activate endothelial production of some vasoconstrictors, which can have detrimental effects on the vascular endothelium. Androgens also activate proliferation, migration, and recruitment of endothelial progenitor cells (EPCs), thereby contributing to vascular repair and restoration of the endothelial layer. In this paper, we consider effects of androgen hormones on EC and EPC function in physiological and pathological conditions.

Effects of androgen and progestin on the proliferation and differentiation of osteoblasts

Osteoporosis is liable to affect patients with gonadal hormone deficiency, and a supplement of androgens may be used to increase bone density of patients with osteoporosis. Since the androgens currently used may cause severe side effects, it is useful to investigate the effect of other androgens and progestin on bone improvement. The aim of the current study was to investigate the effects of pregnenolone (Preg), androstenedione (AD), etiocholanolone (Etio), androsterone (An), nandrolone (NA) and testosterone (T) on the proliferation and differentiation of osteoblasts for potential clinical applications. Human osteoblasts were cultured and treated with androgens and progestin, including Preg, AD, Etio, An, NA, and T, at concentrations of 0, 10^-10, 10^-8, 10^-6 and 10^-5 mol/l. The levels of cell proliferation, alkaline phosphatase (ALP) activity and osteocalcin content were measured and assessed. Preg, AD, Etio, An, and T at concentrations of 10^-10 and/or 10^-8 mol/l significantly improved osteoblast proliferation. NA at concentrations of 10^-10, 10^-8, 10^-6 and 10^-5 mol/l also significantly improved osteoblast proliferation. Preg, AD, Etio, An, NA, and T significantly increased ALP activity and osteocalcin content. The present study demonstrated, for the first time, that Preg, AD, Etio, An, and NA could improve the proliferation and differentiation of osteoblasts in vitro.

Androgen receptor moonlighting in the prostate cancer microenvironment

Androgen receptor (AR) signaling is vital for the normal development of the prostate and is critically involved in prostate cancer (PCa). AR is not only found in epithelial prostate cells but is also expressed in various cells in the PCa-associated stroma, which constitute the tumor microenvironment (TME). In the TME, AR is expressed in fibroblasts, macrophages, lymphocytes and neutrophils. AR expression in the TME was shown to be decreased in higher-grade and metastatic PCa, suggesting that stromal AR plays a protective role against PCa progression. With that, the functionality of AR in stromal cells appears to deviate from the receptor's classical function as described in PCa cells. However, the biological action of AR in these cells and its effect on cancer progression remains to be fully understood. Here, we systematically review the pathological, genomic and biological literature on AR actions in various subsets of prostate stromal cells and aim to better understand the consequences of AR signaling in the TME in relation to PCa development and progression.

Fatty acids rather than hormones restore in vitro angiogenesis in human male and female endothelial cells cultured in charcoal-stripped serum

Charcoal-stripped serum (CSS) is a well-accepted method to model effects of sex hormones in cell cultures. We have recently shown that human endothelial cells (ECs) fail to growth and to undergo in vitro angiogenesis when cultured in CSS. However, the mechanism(s) underlying the CSS-induced impairment of in vitro EC properties are still unknown. In addition, whether there is any sexual dimorphism in the CSS-induced EC phenotype remains to be determined. Here, by independently studying human male and female ECs, we found that CSS inhibited both male and female EC growth and in vitro angiogenesis, with a more pronounced effect on male EC sprouting. Reconstitution of CSS with 17-β estradiol, dihydrotestosterone, or the lipophilic thyroid hormone did not restore EC functions in both sexes. On the contrary, supplementation with palmitic acid or the acetyl-CoA precursor acetate significantly rescued the CSS-induced inhibition of growth and sprouting in both male and female ECs. We can conclude that the loss of metabolic precursors (e.g., fatty acids) rather than of hormones is involved in the impairment of in vitro proliferative and angiogenic properties of male and female ECs cultured with CSS.

EIF2S3Y suppresses the pluripotency state and promotes the proliferation of mouse embryonic stem cells

Eukaryotic translation initiation factor 2, subunit 3, and structural gene Y-linked (EIF2S3Y) is essential for spermatogenesis in mouse models. However, its effect on embryonic stem (ES) cells remains unknown. In our observation, differentiated ES cells showed higher levels of EIF2S3Y. To further elucidate its role in ES cells, we utilized ES-derived EIF2S3Y-overexpressing cells and found that EIF2S3Y down-regulated the pluripotency state of ES cells, which might be explained by decreased histone methylation levels because of reduced levels of ten-eleven translocation 1 (TET1). Moreover, EIF2S3Y-overexpressing cells showed an enhanced proliferation rate, which might be due to increased Cyclin A and Cyclin E levels. This study highlighted novel roles of EIF2S3Y in the pluripotency maintenance and proliferation control of ES cells, which would provide an efficient model to study germ cell generation as well as cancer development using ES cells, thus providing valuable target for clinical applications of ES cells.

Androgen receptor increases hematogenous metastasis yet decreases lymphatic metastasis of renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a gender-biased tumor. Here we report that there is also a gender difference between pulmonary metastasis and lymph node metastasis showing that the androgen receptor (AR)-positive ccRCC may prefer to metastasize to lung rather than to lymph nodes. A higher AR expression increases ccRCC hematogenous metastasis yet decreases ccRCC lymphatic metastases. Mechanism dissection indicates that AR enhances miR-185-5p expression via binding to the androgen response elements located on the promoter of miR-185-5p, which suppresses VEGF-C expression via binding to its 3' UTR. In contrast, AR-enhanced miR-185-5p also promotes HIF2α/VEGF-A expression via binding to the promoter region of HIF2α. Together, these results provide a unique mechanism by which AR can either increase or decrease ccRCC metastasis at different sites and may help us to develop combined therapies using anti-AR and anti-VEGF-C compounds to better suppress ccRCC progression.The incidence of renal cell carcinoma is higher in males than in females due to the different androgen receptor signaling but the molecular mechanisms behind this gender bias are unclear. Here the authors show how androgen receptor expression influences the metastatic route through the regulation of miR-185 and VEGF isoforms.

Expression and regulation of Angiopoietins and their receptor Tie-2 in sika deer antler

The cartilage vascularization and chondrocyte survival are essential for endochondral ossification which occurs in the process of antler growth. Angiopoietins (Ang) is a family of major angiogenic growth factors and involved in regulating the vascularization. However, the expression and regulation of Angs in the antler are still unknown. The aim of this study is to localize the expression of Ang-1, Ang-2 and their receptor Tie-2 in sika deer antler using in situ hybridization and focused on analyzing the regulation of testosterone, estrogen, all-trans-retinoic acid (ATRA) and 9cRA on their expression in antler chondrocytes. The results showed that Ang-1, Ang-2 and Tie-2 were highly expressed in antler chondrocytes. Administration of testosterone to antler chondrocytes led to a notable increase in the expression of Ang-1 and Tie-2, and a reduction in the expression of Ang-2. The similar result was also observed after estrogen treatment. In contrast, ATRA and 9cRA could inhibit the expression of Ang-1 in antler chondrocytes and heighten the expression of Ang-2. Simultaneously, ATRA could downregulate the expression of Tie-2 in antler chondrocytes at 12 and 24 h, while 9cRA upregulate the expression of Tie-2 at 3 and 6 h. Collectively, Ang-1, Ang-2 and Tie-2 are expressed in antler chondrocytes and their expression can be affected by testosterone, estrogen, ATRA and 9cRA.

Protective effects of physiological testosterone on advanced glycation end product‑induced injury in human endothelial cells

The effect of testosterone, a sex steroid, on endothelial cells is controversial as it is uncertain if it has a protective effect on them. Whether physiological testosterone can inhibit the deleterious effects of advanced glycation end products (AGEs) on endothelial cells remains to be elucidated. The present study focused on elucidating the effect of testosterone on the injury of endothelial cells induced by AGEs. Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and treated with AGEs in the presence or absence of various concentrations of testosterone. The cell viability in each group was measured using an MTS assay. Early-stage apoptosis was detected using flow cytometry with Annexin V-fluorescein isothiocyanate/propidium iodide double staining, and the expression levels of apoptosis-associated proteins, B cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax) and caspase-3, were determined using western blot analysis. Oxidative stress and pro-inflammatory parameters in the medium were evaluated using an enzyme-linked immunosorbent assay. The MTS results showed that AGEs significantly decreased the proliferation of HUVECs, whereas a physiological concentration of testosterone alleviated this damage. Physiological concentrations of testosterone protected the HUVECs from AGE-induced apoptosis, mediated by caspase-3 and Bax/Bcl-2. In addition, treatment of the HUVECs with AGEs caused a significant decrease in anti-oxidative parameters, but increased the concentrations of malondialdehyde and tumor necrosis factor-α. The activation of Janus kinase 2 and signal transducer and activator of transcription 3 was significantly increased by incubation with AGEs. However, pre-incubation with a physiological concentration of testosterone attenuated these changes. Therefore, the data obtained in the present study established the potential role of physiological testosterone in ameliorating AGE-induced damage in HUVECs.

Human cells involved in atherosclerosis have a sex

The influence of sex has been largely described in cardiovascular diseases. Atherosclerosis is a complex process that involves many cell types such as vessel cells, immune cells and endothelial progenitor cells; however, many, if not all, studies do not report the sex of the cells. This review focuses on sex differences in human cells involved in the atherosclerotic process, emphasizing the role of sex hormones. Furthermore, we report sex differences and issues related to the processes that determine the fate of the cells such as apoptotic and autophagic mechanisms. The analysis of the data reveals that there are still many gaps in our knowledge regarding sex influences in atherosclerosis, largely for the cell types that have not been well studied, stressing the urgent need for a clear definition of experimental conditions and the inclusion of both sexes in preclinical studies.

Androgens modulate male-derived endothelial cell homeostasis using androgen receptor-dependent and receptor-independent mechanisms

BACKGROUND

Sex-related differences in the role of androgen have been reported in cardiovascular diseases and angiogenesis. Moreover, androgen receptor (AR) has been causally involved in the homeostasis of human prostate endothelial cells. However, levels of expression, functionality and biological role of AR in male- and female-derived human endothelial cells (ECs) remain poorly characterized. The objectives of this work were (1) to characterize the functional expression of AR in male- and female-derived human umbilical vein endothelial cell (HUVEC), and (2) to specifically analyze the biological effects of DHT, and the role of AR on these effects, in male-derived HUVECs (mHUVECs).

RESULTS

Immunohistochemical analyses of tissue microarrays from benign human tissues confirmed expression of AR in ECs from several androgen-regulated and non-androgen-regulated human organs. Functional expression of AR was validated in vitro in male- and female-derived HUVECs using quantitative RT-PCR, immunoblotting and AR-mediated transcriptional activity assays. Our results indicated that functional expression of AR in male- and female-derived HUVECs was heterogeneous, but not sex dependent. In parallel, we analyzed in depth the biological effects of DHT, and the role of AR on these effects, on proliferation, survival and tube formation capacity in mHUVECs. Our results indicated that DHT did not affect mHUVEC survival; however, DHT stimulated mHUVEC proliferation and suppressed mHUVEC tube formation capacity. While the effect of DHT on proliferation was mediated through AR, the effect of DHT on tube formation did not depend on the presence of a functional AR, but rather depended on the ability of mHUVECs to further metabolize DHT.

CONCLUSIONS

(1) Heterogeneous expression of AR in male- and female-derived HUVEC could define the presence of functionally different subpopulations of ECs that may be affected differentially by androgens, which could explain, at least in part, the pleiotropic effects of androgen on vascular biology, and (2) DHT, and metabolites of DHT, generally thought to represent progressively more hydrophilic products along the path to elimination, may have differential roles in modulating the biology of human ECs through AR-dependent and AR-independent mechanisms, respectively.

Dissociation of NSC606985 induces atypical ER-stress and cell death in prostate cancer cells

Castration-resistant prostate cancer (CRPC) is a major cause of prostate cancer (Pca) death. Chemotherapy is able to improve the survival of CRPC patients. We previously found that NSC606985 (NSC), a highly water-soluble camptothecin analog, induced cell death in Pca cells via interaction with topoisomerase 1 and activation of the mitochondrial apoptotic pathway. To further elucidate the role of NSC, we studied the effect of NSC on ER-stress and its association with NSC-induced cell death in Pca cells. NSC produced a time- and dose-dependent induction of GRP78, CHOP and XBP1s mRNA, and CHOP protein expression in Pca cells including DU145, indicating an activation of ER-stress. However, unlike conventional ER-stress in which GRP78 protein is increased, NSC produced a time- and dose-dependent U-shape change in GRP78 protein in DU145 cells. The NSC-induced decrease in GRP78 protein was blocked by protease inhibitors, N-acetyl-L-leucyl-L-leucylnorleucinal (ALLN), a lysosomal protease inhibitor, and epoxomicin (EPO), a ubiquitin-protease inhibitor. ALLN, but not EPO, also partially inhibited NSC-induced cell death. However, both 4-PBA and TUDCA, two chemical chaperons that effectively reduced tunicamycin-induced ER-stress, failed to attenuate NSC-induced GRP78, CHOP and XBP1s mRNA expression and cell death. Moreover, knockdown of NSC induction of CHOP expression using a specific siRNA had no effect on NSC-induced cytochrome c release and NSC-induced cell death. These results suggest that NSC produced an atypical ER-stress that is dissociated from NSC-induced activation of the mitochondrial apoptotic pathway and NSC-induced cell death in DU145 prostate cancer cells.

Androgen actions on endothelium functions and cardiovascular diseases

The roles of androgens on cardiovascular physiology and pathophysiology are controversial as both beneficial and detrimental effects have been reported. Although the reasons for this discrepancy are unclear, multiple factors such as genetic and epigenetic variation, sex-specificity, hormone interactions, drug preparation and route of administration may contribute. Recently, growing evidence suggests that androgens exhibit beneficial effects on cardiovascular function though the mechanism remains to be elucidated. Endothelial cells (ECs) which line the interior surface of blood vessels are distributed throughout the circulatory system, and play a crucial role in cardiovascular function. Endothelial progenitor cells (EPCs) are considered an indispensable element for the reconstitution and maintenance of an intact endothelial layer. Endothelial dysfunction is regarded as an initiating step in development of atherosclerosis and cardiovascular diseases. The modulation of endothelial functions by androgens through either genomic or nongenomic signal pathways is one possible mechanism by which androgens act on the cardiovascular system. Obtaining insight into the mechanisms by which androgens affect EC and EPC functions will allow us to determine whether androgens possess beneficial effects on the cardiovascular system. This in turn may be critical in the prevention and therapy of cardiovascular diseases. This article seeks to review recent progress in androgen regulation of endothelial function, the sex-specificity of androgen actions, and its clinical applications in the cardiovascular system.

Sexual dimorphism in cancer

The incidence of many types of cancer arising in organs with non-reproductive functions is significantly higher in male populations than in female populations, with associated differences in survival. Occupational and/or behavioural factors are well-known underlying determinants. However, cellular and molecular differences between the two sexes are also likely to be important. In this Opinion article, we focus on the complex interplay that sex hormones and sex chromosomes can have in intrinsic control of cancer-initiating cell populations, the tumour microenvironment and systemic determinants of cancer development, such as the immune system and metabolism. A better appreciation of these differences between the two sexes could be of substantial value for cancer prevention as well as treatment.

Androgen receptor (AR) promotes male bladder cancer cell proliferation and migration via regulating CD24 and VEGF

Increasing evidence has proved the pivotal roles of androgen receptor in various diseases, including prostate cancer and bladder cancer. The CD24 has been proved to be correlated to bladder cancer metastasis and tumorigenesis in recent study. This study was aimed to investigate the roles of AR in bladder cell proliferation and metastasis and to explore its potential mechanism. Expressions of AR in two kinds of bladder tumor cells (T24 and UM-UC-3) were analyzed using the CRISPR Activation Plasmid transfection or siRNA-mediated gene. The effects of AR on tumor cell proliferation and migration were also analyzed. Moreover, the effects of CD24 and influence of AR on cell proliferation and metastasis-related protein were also analyzed. The results showed that AR was significantly down-regulated in T24 cells but was significantly overexpressed in UM-UC-3 cells. The up-regulated T24 promotes cell proliferation, but this enhance effect was blocked by silencing CD24. Additionally, the AR overexpression significantly increased the VEGF and CD24 expression. Besides, the migrated bladder cells was increased by the up-regulated AR, but was decreased by silencing CD24 or silencing VEGF. Taken together, our study suggested that the up-regulated AR enhances the male bladder tumor cell proliferation and metastasis via modulating the CD24 and VEGF. This study may provide theoretical basis for the possibility of AR to be a therapeutic target for bladder cancer.

Pharmacologic blockade and genetic deletion of androgen receptor attenuates aortic aneurysm formation

BACKGROUND

Testosterone is theorized to play a major role in the pathophysiology of abdominal aortic aneurysms (AAAs) because this disease occurs primarily in men. The role of the androgen receptor (AR) in the formation of AAAs has not been well elucidated, and therefore, it is hypothesized that androgen blockade will attenuate experimental aortic aneurysm formation.

METHODS

Aortas of 8- to 12-week-old male C57Bl/6 wild-type (WT) mice or male AR knockout (AR(-/-)) mice were perfused with purified porcine pancreatic elastase (0.35 U/mL) to induce AAA formation. Two groups of WT male mice were treated with the AR blockers flutamide (50 mg/kg) or ketoconazole (150 mg/kg) twice daily by intraperitoneal injection. Aortas were harvested on day 14 after video micrometry was used to measure AAA diameter. Cytokine arrays and histologic analysis were performed on aortic tissue. Groups were compared using an analysis of variance and a Tukey post hoc test.

RESULTS

Flutamide and ketoconazole treatment (mean ± standard error of the mean) attenuated AAA formation in WT mice (84.2% ± 22.8% [P = .009] and 91.5% ± 18.2% [P = .037]) compared with WT elastase (121% ± 5.23%). In addition, AR(-/-) mice showed attenuation of AAA growth (64.4% ± 22.7%; P < .0001) compared with WT elastase. Cytokine arrays of aortic tissue revealed decreased levels of proinflammatory cytokines interleukin (IL)-α, IL-6, and IL-17 in flutamide-treated and AR(-/-) groups compared with controls.

CONCLUSIONS

Pharmacologic and genetic AR blockade cause attenuation of AAA formation. Therapies for AR blockade used in prostate cancer may provide medical treatment to halt progression of AAAs in humans.

Human testicular peritubular cells secrete pigment epithelium-derived factor (PEDF), which may be responsible for the avascularity of the seminiferous tubules

Male fertility depends on spermatogenesis, which takes place in the seminiferous tubules of the testis. This compartment is devoid of blood vessels, which are however found in the wall of the seminiferous tubules. Our proteomic study using cultured human testicular peritubular cells (HTPCs) i.e. the cells, which form this wall, revealed that they constitutively secrete pigment epithelium-derived factor, PEDF, which is known to exert anti-angiogenic actions. Immunohistochemistry supports its presence in vivo, in the human tubular wall. Co-culture studies and analysis of cell migration patterns showed that human endothelial cells (HUVECs) are repulsed by HTPCs. The factor involved is likely PEDF, as a PEDF-antiserum blocked the repulsing action. Thus testicular peritubular cells, via PEDF, may prevent vascularization of human seminiferous tubules. Dihydrotestosterone (DHT) increased PEDF (qPCR) in HTPCs, however PEDF expression in the testis of a non-human primate occurs before puberty. Thus PEDF could be involved in the establishment of the avascular nature of seminiferous tubules and after puberty androgens may further reinforce this feature. Testicular microvessels and blood flow are known to contribute to the spermatogonial stem cell niche. Hence HTPCs via control of testicular microvessels may contribute to the regulation of spermatogonial stem cells, as well.

Role of dihydrotestosterone (DHT) on TGF-β1 signaling pathway in epithelial ovarian cancer cells

Purpose

One of the hypotheses regarding the genesis of epithelial ovarian cancer involves the action of androgens on the proliferation of epithelial ovarian cells, as well as inclusion cysts. The purpose of the present study was to evaluate whether DHT causes changes in the TGF-β1 pathway that might modify the anti-proliferative effect of the latter.

Methods

The levels of TGF-β1 protein, of its receptors (TGFBR1 and TGFBR2), of Smad2/3 (canonical signaling pathway protein) and of p21 (cell cycle protein) were assessed in ovarian tissues, epithelial ovarian cancer cell lines (A2780) and control cell lines (HOSE) through the use of immunohistochemistry and immunocytochemistry. Additionally, cell lines were treated with 100 nmol/L DHT, 10 ng/mL of TGF-β1 and DHT + TGF-β1 during 72 h in the presence and absence of a siRNA against androgen receptor. After treatment, TGFBR1 and TGFBR2 levels were detected through Western blotting and p21 was assessed through immunocytochemistry.

Results

Epithelial ovarian cancer tissues showed a decrease in TGF-β1 I receptor (p < 0.05) and a change in Smad2/3 protein levels. Additionally, after treatment of cell lines with DHT, protein levels of TGF-β1 receptors (TGFBR1–TGFBR2) showed a decrease (p < 0.05) that might cause a potential disorder in TGF-β1 response, represented by the significant decrease in p21 protein levels in the presence of DHT (p < 0.001).

Conclusions

Overall, our results indicate a defect in the canonical TGF-β signaling pathway in epithelial ovarian cancer caused by androgen action, thus suggesting eventual changes in such tissue proliferation rates.

Circulating endothelial progenitor cells in type 1 diabetic patients with erectile dysfunction

Circulating endothelial progenitor cells (EPCs) are bone marrow-derived stem cells able to migrate to sites of damaged endothelium and differentiate into endothelial cells, thereby contributing to vascular repair. Recent studies demonstrated a reduction of EPCs in patients with diabetes mellitus or erectile dysfunction (ED). The aim of this study was to evaluate the circulating levels of different EPCs phenotypes and their relation with testosterone levels in young type 1 diabetic patients with ED. We studied 118 consecutively type 1 diabetic patients and 60 age-matched healthy controls. Erectile function was assessed by completing the International Index of Erectile Function (IIEF-5) and EPCs levels by flow cytometry. Testosterone concentrations were evaluated in all the study population. We identified 38 diabetic patients with ED (Group 1) and 80 patients without ED (Group 2). CD34+KDR+CD133+ cells were significantly lower in patients in Group 1 as compared with those in Group 2 [median and interquartile range, n/10(6) events, 12 (6-16) vs. 18 (13-22), P < 0.001)]. In all participants in the study, there was a significant correlation between circulating CD34+KDR+CD133+ cells and testosterone levels (r = 0.410, P < 0.001), which was highest in Group 1, intermediate in Group 2, and lowest in Group 3 (controls). There was a significant correlation between IIEF-5 score and both CD34+KDR+ (r = 0.459, P = 0.003) and CD34+KDR+CD133+ (r = 0.316, P = 0.050) cells among patients of Group 1, as well as between testosterone levels and most of the EPCs phenotypes. Finally, multivariate regression analysis identified levels of circulating CD34+KDR+ cells as an independent risk factor for ED (β-coefficient 0.348, P = 0.007). In conclusion, type 1 diabetic patients with ED show reduced levels of CD34+KDR+CD133+ cells, whose number correlates with IIEF. Further studies are needed to fully understand the exact mechanisms by which testosterone regulates vascular homeostasis.

The therapeutic effects of docosahexaenoic acid on oestrogen/androgen-induced benign prostatic hyperplasia in rats

Benign prostatic hyperplasia (BPH) is one of the major disorders of the urinary system in elderly men. Docosahexaenoic acid (DHA) is the main component of n-3 polyunsaturated fatty acids (n-3 PUFAs) and has nerve protective, anti-inflammatory and tumour-growth inhibitory effects. Here, the therapeutic potential of DHA in treating BPH was investigated. Seal oil effectively prevented the development of prostatic hyperplasia induced by oestradiol/testosterone in a rat model by suppressing the increase of the prostatic index (PI), reducing the thickness of the peri-glandular smooth muscle layer, inhibiting the proliferation of both prostate epithelial and stromal cells, and downregulating the expression of androgen receptor (AR) and oestrogen receptor α (ERα). An in vitro study showed that DHA inhibited the growth of the human prostate stromal cell line WPMY-1 and the epithelial cell line RWPE-1 in a dose- and time-dependent manner. In both cell lines, the DHA arrested the cell cycle in the G2/M phase. In addition, DHA also reduced the expression of ERα and AR in the WPMY-1 and RWPE-1 cells. These results indicate that DHA inhibits the multiplication of prostate stromal and epithelial cells through a mechanism that may involve cell cycle arrest and the downregulation of ERα and AR expression.

Androgen receptor in human endothelial cells

Androgen receptor (AR) is a ligand-inducible transcription factor, and a member of the steroid-thyroid-retinoid receptor superfamily, that mediates the biological effects of androgens in a wide range of physiological and pathological processes. AR expression was identified in vascular cells nearly 20 years ago, and recent research has shown that AR mediates a variety of actions of androgens in endothelial and vascular smooth muscle cells. In this mini-review, we review evidence indicating the importance of AR in human endothelial cell (HUVEC) homeostatic and pathogenic processes. Although a role for AR in the modulation of HUVEC biology is evident, the molecular mechanisms by which AR regulates HUVEC homeostasis and disease processes are not fully understood. Understanding these mechanisms could provide critical insights into the processes of pathogenesis of diseases ranging from cardiovascular disease to cancer that are major causes of human morbidity and mortality.

The evaluation of involvement of angiotensin II, its receptors, and androgen receptor in endometrial cancer

Endometrial cancer (EC) is the most common gynecological malignancy. Alterations of angiogenic factors including angiotensin (AngII) or VEGF are observed in EC. Expression of angiotensin receptor 1 (AT1) is correlated with EC. Moreover, the expression of VEGF is up-regulated by AngII. Androgens are involved in the pathogenesis of EC. Genetic variations in androgen receptor (AR) gene may increase EC risk. This review proved strong correlation among EC, AngII, its receptors and AR, where AT influence on AR and, as a result, induce the expression of genes related to carcinogenesis.

The prevention and treatment effects of tanshinone IIA on oestrogen/androgen-induced benign prostatic hyperplasia in rats

Benign prostatic hyperplasia (BPH) is one of the major diseases of the urinary system in elderly men. Tanshinone IIA (Tan IIA) is the active ingredient extracted from the traditional Chinese medicine Salvia, and it has effects of anti-oxidation, anti-inflammation, vascular smooth muscle relaxation and tumour growth inhibition. The present study aimed to investigate the therapeutic potential of Tan IIA in the prevention and treatment of BPH. In a rat model of oestradiol/testosterone-induced BPH, Tan IIA inhibited the increase in the thickness of the peri-glandular smooth muscle layer, suppressed the expression of proliferating cell nuclear antigen (PCNA) in both prostate epithelial cells and stromal cells, downregulated the expression of androgen receptor (AR), oestrogen receptor α (ERα), cyclin B1 (CCNB1) and cyclin D1 (CCND1), and effectively prevented the development of the disorder. In vitro, Tan IIA inhibited the proliferation of human prostate stromal cell line WPMY-1 and epithelial cell line RWPE-1 in a dose- and time-dependent manner. In WPMY-1 cells, Tan IIA treatment arrested the cell cycle at the G2/M phase and downregulated the expression of CCNB1. However, in RWPE-1 cells, Tan IIA treatment arrested cell cycle at the G0/G1 phase and reduced the expression of CCND1. Tan IIA also reduced the expression of ERα and AR in WPMY-1 and RWPE-1 cells. These results suggest that Tan IIA can inhibit the growth of prostate stromal and epithelial cells both in vivo and in vitro by a mechanism that may involve arresting the cell cycle and downregulating ERα and AR expression.

Aging impairs VEGF-mediated, androgen-dependent regulation of angiogenesis

There is a progressive impairment of vascular repair mechanisms with advancing age concomitant with a steady decline in circulating androgen levels in men. Emerging evidence indicates androgens regulate angiogenesis; however, little research has focused on the impact of age upon androgen-mediated regulation of angiogenic mechanisms. Human dermal fibroblasts from young (<30 years) and older (>65 years) men were incubated with DHT, with or without androgen receptor antagonist hydroxyflutamide, or phosphoinositide 3-kinase inhibitor. Fibroblast-conditioned medium was used to stimulate angiogenic functions in human umbilical vein endothelial cells. Nuclear fractionation and fluorescence microscopy were used to study androgen receptor (AR) distribution. Conditioned medium from fibroblasts of young men, but not old men, treated with DHT produced a 3-fold increase in human umbilical vein endothelial cell tubulogenesis and 2-fold increase in migration via increased vascular endothelial growth factor (VEGF) expression and secretion, predominantly of VEGF145. DHT-induced VEGF secretion from fibroblasts of young men was AR-dependent and increased AKT phosphorylation, which was abrogated by phosphoinositide 3-kinase inhibition. By contrast, fibroblasts from older men were unresponsive to DHT and lacked androgen-mediated enhancement in VEGF production. These findings were associated with reduced AR nuclear translocation in old fibroblasts. The failure of DHT-induced paracrine stimulation of angiogenesis in fibroblasts from older men is likely due to defective nuclear translocation of AR. This first demonstration of androgen resistance (or insensitivity) acquired by human fibroblasts with aging suggests that pharmacological testosterone therapy for old men may be less effective in enhancing angiogenesis and facilitating tissue regeneration mechanisms reliant on paracrine release of VEGF.