Testosterone and erectile function: from basic research to a new clinical paradigm for managing men with androgen insufficiency and erectile dysfunction

Association between testosterone levels and RigiScan parameters of patients with erectile dysfunction

Background

It is difficult to diagnose hypogonadism because of the lack of objective assessments of erectile dysfunction (ED), which is caused by hypogonadism.

Aim

To provide a new approach for diagnosing hypogonadism, this study evaluated the efficacy of nocturnal penile tumescence and rigidity (NPTR) testing with RigiScan for patients with ED with and without hypogonadism.

Methods

From June 2021 to February 2023, 133 patients with ED (62 with hypogonadism and 71 without) underwent NPTR testing at the Department of Andrology. A detailed history of all participants was obtained. All participants also underwent a physical examination, sex hormone testing, and ultrasound examination of the cavernous vessels of the penis.

Outcomes

Patient characteristics, sex hormone serum levels, and RigiScan Plus data of NPTR testing of patients with ED were obtained and evaluated.

Results

Between the groups, there were no significant differences in age, body mass index, or erectile function score or in the prevalence of smoking, drinking, diabetes, hypertension, and hyperlipidemia. RigiScan data revealed differences in erection episodes per night, average event rigidity, erection durations, and percentage of tumescence greater than baseline, which were significantly lower in the testosterone-deficient group than in the normal testosterone group. The average event rigidity of the tip displayed the largest area under the curve value, with a sensitivity of 67.6%, a specificity of 85.5%, and a cutoff value of 52.50.

Clinical Implications

Our findings may allow appropriate patients to receive testosterone replacement therapy, which has been shown to be an effective treatment for hypogonadism.

Strengths and Limitations

This is the first study of its kind to perform a comprehensive review of the association between hypogonadism and RigiScan parameters. This study was limited by its small sample size.

Conclusion

RigiScan parameters of patients with ED and testosterone deficiency were significantly lower than those of patients with normal testosterone; therefore, RigiScan is useful for the differential diagnosis of patients with ED caused by hypogonadism.

Investigating the prevalence of erectile dysfunction among men exposed to organophosphate insecticides

INTRODUCTION

Erectile dysfunction (ED) poses a significant disease morbidity and contributor to male infertility, where an estimated 20-40% of men are affected annually. While several risk factors have been identified in the etiology of ED (e.g., aging, heart disease, diabetes, and obesity), the complete pathogenesis remains to be elucidated. Over the last few decades, the contribution of environmental exposures to the pathogenesis of ED has gained some attention, though population studies are limited and results are mixed. Among environmental contaminants, organophosphate (OP) insecticides represent one of the largest chemical classes, and chlorpyrifos is the most commonly used OP in the U.S. OP exposure has been implicated in driving biological processes, including inflammation, reactive oxygen species production, and endocrine and metabolism disruption, which have been demonstrated to adversely affect the hypothalamus and testes and may contribute to ED. Currently, studies evaluating the association between OPs and ED within the U.S. general population are sparse.

METHODS

Data were leveraged from the National Health and Nutrition Examination Survey (NHANES), which is an annually conducted, population-based cross-sectional study. Urinary levels of 3,5,6-trichloro-2-pyridinol (TCPy), a specific metabolite of the most pervasive OP insecticide chlorpyrifos, were quantified as measures of OP exposure. ED was defined by responses to questionnaire data, where individuals who replied "sometimes able" or "never able" to achieve an erection were classified as ED. Chi-square, analysis of variance (ANOVA), and multivariable, weighted linear and logistic regression analyses were used to compare sociodemographic variables between quartiles of TCPy exposure, identify risk factors for TCPy exposure and ED, and to analyze the relationship between TCPy and ED.

RESULTS

A total of 671 adult men were included in final analyses, representing 28,949,379 adults after survey weighting. Approximately 37% of our cohort had ED. Smoking, diabetes, aging, Mexican-American self-identification, and physical inactivity were associated with higher ED prevalence. Analysis of TCPy modeled as a continuous variable revealed nonsignificant associations with ED (OR = 1.02 95% CI [0.95, 1.09]). Stratification of total TCPy into quartiles revealed increased odds of ED among adults in the second and fourth quartiles, using the first quartile as the reference (OR = 2.04 95% CI [1.11, 3.72], OR = 1.51 95% CI [0.58, 3.93], OR = 2.62 95% CI [1.18, 5.79], for quartiles 2, 3, and 4, respectively).

CONCLUSIONS

The results of our study suggest a potential role for chlorpyrifos and other OPs the pathogenesis of ED. Future studies are warranted to validate these findings, determine clinical significance, and to investigate potential mechanisms underlying these associations.

The roles of sex hormones in the pathophysiology of age-related sarcopenia and frailty

Background

Sarcopenia is an age-related condition characterized by a progressive and systemic decline in skeletal muscle mass, quality, and strength. The incidence of sarcopenia contains sex-specific aspects, indicating the contribution of sex hormones to its pathophysiology. This review focuses on changing trends in sarcopenia, discusses alterations in definitions and diagnostic criteria, and emphasizes the association between sarcopenia and sex hormones.

Methods

A literature search was performed on PubMed for related articles published between 1997 and December 2023 using appropriate keywords.

Main Findings Results

Advances in research have emphasized the significance of muscle quality and strength over muscle mass, resulting in new diagnostic criteria for sarcopenia. Androgens demonstrated anabolic effects on skeletal muscles and played a significant role in the pathophysiology of sarcopenia. In clinical settings, androgen replacement therapy has exhibited certain positive outcomes for treating sarcopenia, despite concerns about potential side effects. Conversely, estrogen is involved in skeletal muscle maintenance, but the detailed mechanisms remain unclear. Moreover, results regarding the clinical application of estrogen replacement therapy for treating sarcopenia remained inconsistent.

Conclusion

The elucidation of molecular mechanisms that involve sex hormones is eagerly awaited for novel therapeutic interventions for sarcopenia.

Male- and female-specific reproductive risk factors across the lifespan for dementia or cognitive decline: a systematic review and meta-analysis

BACKGROUND

Sex difference exists in the prevalence of dementia and cognitive decline. The impacts of sex-specific reproductive risk factors across the lifespan on the risk of dementia or cognitive decline are still unclear. Herein, we conducted this systemic review and meta-analysis to finely depict the longitudinal associations between sex-specific reproductive factors and dementia or cognitive decline.

METHODS

PubMed, EMBASE, and Cochrane Library were searched up to January 2023. Studies focused on the associations of female- and male-specific reproductive factors with dementia or cognitive decline were included. Multivariable-adjusted effects were pooled via the random effect models. Evidence credibility was scored by the GRADE system. The study protocol was pre-registered in PROSPERO and the registration number is CRD42021278732.

RESULTS

A total of 94 studies were identified for evidence synthesis, comprising 9,839,964 females and 3,436,520 males. Among the identified studies, 63 of them were included in the meta-analysis. According to the results, seven female-specific reproductive factors including late menarche (risk increase by 15%), nulliparous (11%), grand parity (32%), bilateral oophorectomy (8%), short reproductive period (14%), early menopause (22%), increased estradiol level (46%), and two male-specific reproductive factors, androgen deprivation therapy (18%), and serum sex hormone-binding globulin (22%) were associated with an elevated risk of dementia or cognitive decline.

CONCLUSIONS

These findings potentially reflect sex hormone-driven discrepancy in the occurrence of dementia and could help build sex-based precise strategies for preventing dementia.

Effects of transplantation of umbilical cord blood mononuclear cells into the scrotum on sexual function in elderly mice

Aim: This study investigated the effect of allografting umbilical cord blood mononuclear cells (UCBMCs) into the scrotum on sexual function in male elderly mice. Methods: UCBMCs were injected once into the scrotal sheath cavity of elderly mice. Results: The transplanted UCBMCs survived in the scrotal sheath cavity for 1 month. The mice had significantly increased blood testosterone concentrations, cyclic guanosine monophosphate (cGMP) levels and total nitric oxide synthase (T-NOS) activity in the corpus cavernosum and an increase in the number of mouse matings within 30 min (all p = 0.000). Conclusion: Scrotum-implanted UCBMCs improve the sexual function of male elderly mice through testosterone production and the NOS/cGMP pathway, which may provide an innovative transplantation approach for the treatment of erectile dysfunction.

Effect of hypoandrogenism on expression of transient receptor potential vanilloid channels in rat penile corpus cavernosum and erectile function

BACKGROUND

Hypoandrogenism is a cause of erectile dysfunction (ED). Vascular smooth muscle cell contraction and relaxation are regulated by TRPV1-4 channels. However, the influence of hypoandrogenism on TRPV1-4 and its relationship with erectile function remain unclear.

AIM

To reveal whether hypoandrogenism affects erectile function by influencing TRPV1-4 expression in the corpus cavernosum of rats.

METHODS

Male Sprague-Dawley rats (N = 36) aged 8 weeks were assigned to 6 groups at random (n = 6): sham operation, castrated, castrated + testosterone replacement, sham operation + transfection, castrated + transfection, and castrated + empty transfection. Four weeks after castration, 20 μL of lentiviral vector (1 × 108 TU/mL) carrying the TRPV4 gene was injected into the penile cavernous tissue of the transfection groups. One week after transfection, the maximum intracavernous pressure (ICPmax)/mean arterial pressure (MAP) and the content of TRPV1-4, phosphorylated eNOS (p-eNOS)/eNOS, and nitric oxide (NO) in penile cavernous tissue of each group were measured.

OUTCOMES

Under low androgen conditions, TRPV4 expression in endothelial cells in the rat penile cavernosum was sharply reduced, resulting in a decrease in p-eNOS/eNOS and NO content, which could inhibit erectile function.

RESULTS

In rat penile cavernous tissue, TRPV1-4 was expressed in the cell membranes of endothelial cells and smooth muscle cells. The ICPmax/MAP and the content of TRPV4, p-eNOS/eNOS, and NO end product nitrite level in rat penile cavernous tissue was markedly reduced in the castrated group as compared with the sham group (P < .05). The ICPmax/MAP and the content of TRPV4, p-eNOS/eNOS, and NO end product nitrite level in rat penile cavernous tissue were markedly improved in the castrated + transfection group vs the castrated group (P < .01).

CLINICAL IMPLICATIONS

Upregulation of TRPV4 expression in penile cavernosum tissue might be a viable therapeutic for ED caused by hypoandrogenism.

STRENGTHS AND LIMITATIONS

The specific mechanism of TRPV4 in ED needs to be further verified by androgen receptor or TRPV4 gene knockout experiments.

CONCLUSION

Hypoandrogenism may cause ED by reducing the expression of TRPV4 in rat penile cavernous tissue. Upregulation of TRPV4 expression in penile cavernous tissue can increase the ratio of p-eNOS/eNOS and NO levels and ameliorate the erectile function of castrated rats.

Low androgen levels induce ferroptosis of rat penile cavernous endothelial cells

Background

Endothelial dysfunction caused by low androgen levels in penile tissue can lead to erectile dysfunction. The exact mechanism of endothelial dysfunction has not been thoroughly studied.

Objective

The study sought to verify whether low androgen levels induce ferroptosis of endothelial cells in rat penile tissue.

Methods

Rat penile cavernous endothelial cells (CP-R133) were divided into a no-androgen group (Dihydrotestosterone (DHT): 0 nmol/L), very low-androgen group (DHT: 0.1 nmol/L), low-androgen group (DHT: 1 nmol/L), DHT = 10 nmol/L group, DHT (0 nmol/L) + ferrostatin-1 (Fer-1) group, DHT (0.1 nmol/L) + Fer-1 group, DHT (1 nmol/L) + Fer-1 group, DHT (10 nmol/L) + Fer-1 group. Cell viability, intracellular ferrous ion (Fe2+), malondialdehyde (MDA), GSH into oxidized glutathione (GSSG), reactive oxygen species (ROS), nitric oxide (NO), transferrin receptor 1 protein (TfR1), solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), acyl-CoA synthetase long-chain family member 4 (ACSL4), endothelial nitric oxide synthase (eNOS), and phospho-eNOS (p-eNOS) were detected.

Outcomes

Low androgen levels could induce ferroptosis of rat penile cavernous endothelial cells in vivo by upregulating the expressions of TfR1 and ACSL4 and downregulating the expressions of SLC7A11 and GPX4.

Results

Cell viability, the levels of glutathione (GSH), NO, SLC7A11, GPX4, and p-eNOS/eNOS in the DHT = 0 nmol/L group were lower than those in the other groups (P < .05). The levels of Fe2+, ROS, MDA, GSSG, TfR1, and ACSL4 in the DHT = 0 nmol/L group were higher than those in the other groups (P < .05). Cell viability and the levels of GSH, NO, SLC7A11, GPX4, and p-eNOS/eNOS in the DHT = 1 nmol/L group were lower than those in the DHT (1 nmol/L) + Fer-1 group, DHT = 10 nmol/L group, and DHT (10 nmol/L) + Fer-1 group (P < .05). The levels of Fe2+, ROS, MDA, GSSG, TfR1, and ACSL4 in the DHT = 1 nmol/L group were higher than those in the DHT (1 nmol/L) + Fer-1 group, DHT = 10 nmol/L group, and DHT (10 nmol/L) + Fer-1 group (P < .05).

Clinical Implications

A ferroptosis inhibitor might be a novel drug for treating erectile dysfunction caused by low androgen level.

Strengths and Limitations

The results of this study need to be further confirmed in in vitro and in human studies. Meanwhile, further investigation is needed to clarify whether low androgen levels affect ferroptosis of rat penile cavernous smooth muscle and nerve cells.

Conclusion

Low androgen levels can induce ferroptosis of endothelial cells in rat penile tissue. Inhibition of ferroptosis can reverse endothelial dysfunction caused by low androgen levels.

Effects of comfort food diet on the penile morphology of stressed rats

Purpose

To investigate the effects of chronic stress, associated or not with comfort food, on the morphology of the penis.

Materials & methods

Thirty-two adult Wistar rats were divided into four experimental groups: Control group (C), receiving standard rat chow, and under normal conditions; Stressed group (S), receiving standard chow, and submitted to stressful situations; Control + comfort food group (C + CF), receiving standard chow and comfort food, and under normal conditions; and Stressed + comfort food group (S + CF), receiving standard chow and comfort food, and submitted to stressful situations. At 10 weeks of age, food supply and stress were initiated. All groups had ad libitum access to standard chow and water, and groups receiving comfort food also had access to Froot Loops®. Chronic stress was induced by restriction, animals were contained daily in polypropylene tubes for 2 h, for eight weeks. After eight weeks all animals were killed; penises were removed for histomorphometric analysis.

Results

Body mass was similar among the groups. Food intake in S + CF group was lower than in other groups. Concerning food preference, groups C + CF and S + CF preferred comfort food over the standard chow, with this preference being higher in S + CF than in C + CF. The area of the corpora cavernosa without tunica albuginea was lower in group S + CF than in group C. Most interestingly, the surface density of connective tissue in the corpora cavernosa was higher in groups S and S + CF compared to group C. In contrast, smooth muscle surface density was markedly lower in S + CF compared to groups C and C + CF, while group S also had reduced smooth muscle in comparison to group C.

Conclusion

Chronic stress caused a morphological alteration on penile histomorphometry. Also, stress increased the preference for comfort foods which caused more deleterious effects in some parameters.

Stepwise Frontal Analysis Coupled with Affinity Chromatography: A Fast and Reliable Method for Potential Ligand Isolation and Evaluation from Mahuang-Fuzi-Xixin Decoction

Mahuang-Fuzi-Xixin Decoction (MFXD) is widely used in the treatment of asthma, however, the functional components in the decoction targeting beta2-adrenoceptor (β₂ -AR) remain unclear. Herein, we immobilized the haloalkane dehalogenase (Halo)-tagged β₂ -AR on the 6-chlorocaproic acid-modified microspheres. Using the affinity stationary phase, the interactions of four ligands with the receptor were analyzed by stepwise frontal analysis. The association constants were (4.75±0.28)×10⁴  M^-1 for salbutamol, (2.93±0.15)×10⁴  M^-1 for terbutaline, (1.23±0.03)×10⁴  M^-1 for methoxyphenamine, (5.67±0.38)×10⁴  M^-1 for clorprenaline at high-affinity binding site, and (2.73±0.05)×10³  M^-1 at low-affinity binding site. These association constants showed the same rank order as the radioligand binding assay, demonstrating that immobilized β₂ -AR had capacity to screen bioactive compounds binding to the receptor while stepwise frontal analysis could predict their binding affinities. Application of the immobilized receptor in analysis of MFXD by chromatographic method revealed that ephedrine, aconifine, karakoline, and chasmanine were the bioactive compounds targeting β₂ -AR. Among them, ephedrine and chasmanine exhibited association constants of (2.94±0.02)×10⁴ M^-1 and (4.60±0.15)×10⁴  M^-1 to the receptor by stepwise frontal analysis. Molecular docking analysis demonstrated that ephedrine, chasmanine, and the other two compounds interact with β₂ -AR through the same pocket involving the key amino acids such as Asn312, Asp113, Phe289, Trp286, Tyr316, and Val114. As such, we reasoned that the four compounds dominate the therapeutic effect of MFXD against asthma through β₂ -AR mediating pathway. This work shed light on the potential of immobilized β₂ -AR for drug discovery and provided a valuable methodology for rapid screening.

Impact of anabolic androgenic steroids on male sexual and reproductive function: a systematic review

INTRODUCTION

Anabolic-androgenic steroids (AASs) are a complex cluster of synthetic derivatives of testosterone. AAS abuse is considered a major public health issue since it has increased among young/adolescent males. The use of steroids has a prevalence rate of 14% in young athletes and 30-75% in professional athletes or bodybuilders. AASs simulate the testosterone mechanism, binding the intracellular androgen receptor, and dysregulating the normal hypothalamic-pituitary-gonadal axis in the same way as exogenous testosterone. Abuse can produce several side effects on organs, such as the genital system. The physio-pathological mechanisms that cause AAS abuse-related, genital system disorders in humans are still not completely known.

EVIDENCE ACQUISITION

This study focuses on the effect of AASs on the male reproductive organs in humans and animals.

EVIDENCE SYNTHESIS

A systematic review was performed using SCOPUS, PubMed, Google Scholar, and Web of Sciences database up to 31 December 2021 using the keywords: "anabolic-androgenic steroids," "erectile dysfunction," "spermatogenesis" and "infertility;" (anabolic agents) "erectile dysfunction," "spermatogenesis" and "infertility." The review of the literature identified 66 articles published until 2021. Sixty-two articles were included. The use of AASs induces testicular atrophy and azoospermia known as "anabolic steroid-induced hypogonadism." Anabolic steroid induced infertility is characterized by oligo or azoospermia and abnormalities in sperm motility and morphology. Although sperm quality recovers in most cases within 4 months of stopping anabolic steroid abuse, the negative consequences on spermatogenesis can take up to 3 years to disappear. Human studies reported a positive correlation between AAS abuse in athletes and an increase in morphologically abnormal spermatozoa. Animal studies showed the destruction of Leydig cells and testicular atrophy in animals treated with cycles of AASs.

CONCLUSIONS

The present review of the literature highlights how little is known about the action of AASs on the male genital system. However, although their use is prohibited in many countries, the black market for these substances is still very frequent. The scientific landscape still has a lot to invest in the research of AAS on the male genital system to make young people even more aware of the negative aspects of these substances, contributing to the reduction of these products in an inappropriate way.

Does Testosterone Salvage PDE5i Non-Responders? A Scoping Review

Erectile physiology, in order to function normally, requires the complex coordination of endocrine, neurocognitive, neuromuscular and vascular mechanisms. Testosterone (T) influences male sexuality as well as penile erections at multiple levels, including a direct influence on the nitric oxide synthase (NOS)/cGMP/phosphodiesterase 5 pathway in the penis. However, the precise role of testosterone replacement (TRT) to “salvage” men with mixed ED failing phosphdiesterase-5 inhibitors (PDE5i) remains unclear. We conducted a scoping review identifying the rationale for TRT in ED failing PDE5i, and we critically discuss clinical trials that have examined TRT in the setting of PDE5i use. Overall, TRT replacement appears to be well tolerated and may enhance the response to PDE5i and quality of life, particularly for men with mixed ED, and particularly among men with very low levels of testosterone. However, most of the available literature examines concurrent TRT alone or simultaneous TRT + PDE5i usage, without necessarily selecting for PDE5i failure cases. The present studies are limited to heterogenous studies with small sample sizes, without an exact predominant etiologic factor causing ED. Furthermore, studies showing the most benefit are non-placebo-controlled trials; however, the correction of more profound hypogonadism may lead to an improved response to PDE5i. Stronger conclusions would require properly selected patient populations and larger placebo-controlled RCTs.

Erectile Dysfunction: Pharmacological Pathways with Understudied Potentials

Erectile dysfunction (ED) is a public health concern worldwide. In the past, it was perceived as a phenomenon attributed to age advancement. However, more individuals are affected every year that do not fall under that age criterion. Epidemiological research revealed that this abnormality has an association with endothelial dysfunction connected to several cardiovascular (CV) risk factors. Currently, ED is interpreted as a clinical marker for future adverse events and not only as a present health issue that negatively affects the quality of life. The management of ED involves lifestyle modifications, therapeutic optimization for comorbid conditions, and pharmacological and psychosexual therapy. Phosphodiesterase type 5 (PDE5) inhibitors are the first-line pharmacological agents to be prescribed for such a condition. Nonetheless, other pharmacological pathways and agents remain underinvestigated or were investigated at some stage. This review aimed to present to future researchers interested in this field with some pharmacological agents that showed favorable effects on a limited number of studies on human subjects or experimental models.

Androgens and Non-Genomic vascular responses in hypertension

Arterial hypertension is a global public health concern. In the last few years, the interest in androgen deficiency has been growing, and the association between androgens and high blood pressure (BP) is still controversial. One purpose of this review was to summarize the available findings in order to clarify whether male sex steroid hormones have beneficial or harmful effect on BP. The second purpose was to enhance the recognition of the acute non-genomic sex-independent vasorelaxing effect of androgens. Remarkably, BP variation is expected to be a consequence of the androgen-induced vasorelaxation which reduces systemic BP; hence the in vivo vasodepressor, hypotensive, and antihypertensive responses of androgens were also analyzed. This article reviews the current understanding of the physiological regulation of vascular smooth muscle contractility by androgens. Additionally, it summarizes older and more recent data on androgens, and some of the possible underlying mechanisms of relaxation, structural-functional differences in the androgen molecules, and their designing ability to induce vasorelaxation. The clinical relevance of these findings in terms of designing future therapeutics mainly the 5-reduced metabolite of testosterone, 5β-dihydrotestosterone, is also highlighted. Literature collected through a PubMed database search, as well as our experimental work, was used for the present review.

Evaluation of Serum Testosterone Levels Following Three Months of SA3X (Spilanthes acmella) Supplementation

Introduction: Low testosterone is usually associated with erectile dysfunction (ED). SA3X (Spilanthes acmella) has proven to be effective in alleviating symptoms of ED, which could be due to an alteration in serum testosterone levels. This study was carried out to evaluate the change in testosterone levels in participants with ED supplemented with SA3X for three months.

Materials and Methods: A group of 326 sexually active men aged 25-60 years was investigated from November 2021 to May 2022 in Hyderabad. The participants were subjected to supplementation with SA3X capsules for three months, and a follow-up was done at the end of six months with serum testosterone assessment in each visit. The change in testosterone level was assessed using a mixed model repeated measures analysis.

Results: A significant increase was observed in the mean serum testosterone levels by the end of the second month (323.91 ± 13.76 ng/dL vs. 309.84 ± 14.11 ng/dL; p=0.03) and third month (332.27 ± 12.85 ng/dL vs. 309.84 ± 14.11 ng/dL; p<0.01) of SA3X therapy. The adjusted mean change in testosterone levels was found to be 22.43 ng/dL at the end of the three-month therapy. It was also observed that the change in testosterone levels was significantly lower in participants having diabetes mellitus, hypercholesterolemia, and a history of substance abuse. However, participants on phosphodiesterase-5 inhibitors had an increased change in testosterone levels.

Conclusion: Supplementation with SA3X capsules for three months increases the serum testosterone levels. However, causality cannot be ascertained owing to the longitudinal nature of the study, and further controlled trials are required for the same.

Erectile dysfunction in hypospadiac male adult rats induced by maternal exposure to di-n-butyl phthalate

For the treatment of hypospadias, a significant number of studies focus on penile reconstruction. However, scant attention is given to sexual behavior of hypospadiac patients and underlying mechanisms. A rat model of hypospadias was constructed by maternal di-n-butyl phthalate (DBP) exposure (800 mg/kg/day by gavage during gestational days 14-18). Ten-week-old male rats with hypospadias undertook significantly decreased penis/body weight ratio, reduced testis/body weight ratio, lower serum testosterone level and thinner myelin sheath thickness of cavernosum nerves. Meanwhile, erectile dysfunction (ED) was found in hypospadiac rats, which showed significant increases in transforming growth factor-β1 (TGF-β1) protein expression and decreases in the expression of alpha smooth muscle actin (α-SMA) protein, neuronal and endothelial nitric oxide synthase protein (nNOS and eNOS). In addition, phosphorylated protein kinase B/protein kinase B (pAkt/Akt) ratios were remarkably lower, but the Bcl-2-associated X protein (Bax)/Bcl-2 ratios, caspase-3 protein expression, nuclear factor erythroid 2-related factor 2/ Kelch-like ECH-associated protein 1 (Nrf2/Keap-1) ratios, NAD(P)H dehydrogenase quinone 1(NQO1) protein expression and heme oxygenase-1 (HO-1) protein expression were higher in the hypospadias groups than the control group. Notably, ED is comorbid with hypospadias in cases. Penile fibrosis, testosterone deficiency, and endothelial dysfunction lead to ED in hypospadias induced by DBP eventually, which might be explained by activating Akt/Bad/Bax/caspase-3 pathway, Nrf2/Keap-1 pathway and suppressing NOS/cGMP pathway in penis.

Low androgen level impairs erectile function of rat by regulating the Ng/CaN/AKT/eNOS pathway in penile corpus cavernosum

BACKGROUND

The mechanism by which low androgen status inhibit erectile function has not yet been clearly elucidated. Neurogranin (Ng) is a Ca²⁺ -sensitive calmodulin binding protein that is expressed in endothelial cells and regulates eNOS function.

OBJECTIVES

To investigate whether low androgen status inhibit erectile function by regulating the Ng/CaN/AKT/eNOS pathway in the penile cavernous tissue of rats.

MATERIALS AND METHODS

Thirty-six 8-week-old male Sprague-Dawley rats were randomly divided into six groups as follows (n = 6): 4-week control group (4w-control), 4-week castration group (4w-cast), 4-week castration+testosterone replacement group (4w-cast+T), 8-week control group (8w-control), 8-week castration group (8w-cast), and 8-week castration+testosterone replacement group (8w-cast+T). Four weeks and eight weeks after surgery, the ratio of the maximum intracavernous pressure/mean arterial pressure (ICPmax/MAP) was examined. The level of NO and the expression of Ng, calcineurin (CaN), AKT, p-AKT(S473), eNOS, and p-eNOS(Ser1177) in the penile cavernous tissue of each group were determined.

RESULTS

Ng and CaN were mainly expressed in the membrane and cytoplasm of endothelial cells and smooth muscle cells in the penile cavernous tissue of rats. The ICPmax/MAP and the concentration of NO in the cast group were significantly lower than those in the control group and cast+T replacement group (p < 0.01). The expression of Ng and the ratios of p-AKT/AKT and p-eNOS/eNOS in the penile cavernous tissue of rats in the cast group were significantly lower than those in the control group and cast+T replacement group (p < 0.01). The expression of CaN in the penile cavernous tissue of rats in the cast group was significantly increased compared with that in the control group and the cast+T replacement group (p < 0.01).

CONCLUSION

Inhibiting the expression of Ng and subsequently upregulating the expression of CaN in the rat penile cavernous tissue was one of the upstream mechanisms of low androgen status inhibiting erectile function by inhibiting the AKT/eNOS signaling pathway.

Associations among romantic and sexual partner history and muscle dysmorphia symptoms, disordered eating, and appearance- and performance-enhancing drugs and supplement use among cisgender gay men

This study examined relationship status (e.g., single versus not single) and number of sexual partners in relation to muscularity- and disordered eating-related attitudes and behaviors among 1090 cisgender gay men enrolled in The PRIDE Study in 2018. Participants completed measures assessing muscle dysmorphia (MD) symptoms, disordered eating attitudes and behaviors, and appearance- and performance-enhancing drug or supplement (APEDS) use. In linear regression models adjusting for theoretically relevant covariates, neither relationship status nor number of past-month sexual partners was associated with disordered eating attitudes. In terms of MD symptoms, single (versus not single) relationship status was associated with greater appearance intolerance, and a greater number of sexual partners was associated with greater drive for size and functional impairment. In adjusted logistic regression models, a greater number of past-month sexual partners was associated with use of anabolic-androgenic steroids, synthetic performance-enhancing substances, protein supplements, and creatine supplements, as well as greater likelihood of engaging in compelled/driven exercise. Across all associations, effect sizes were generally small. Overall, results support that inquiring about sexual partners may have utility in evaluating risk for muscularity-oriented attitudes and behaviors among cisgender gay men. Future work will need to replicate these findings, particularly in more diverse samples.

Human Papillomavirus Infection and the Risk of Erectile Dysfunction: A Nationwide Population-Based Matched Cohort Study

Background: Male patients with genital warts are known for higher rates of sexual dysfunction. This study was conducted to investigate whether human papillomaviruses (HPV) infection is associated with an increased risk of erectile dysfunction (ED). Methods: Patients aged over 18 with HPV infection (n = 13,296) and propensity score-matched controls (n = 53,184) were recruited from the Longitudinal Health Insurance Database (LHID). The primary endpoint was the diagnosis of ED. Chi-square tests were used to analyze the distribution of demographic characteristics. The Cox proportional hazards regression was used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the development of ED in both groups, after adjusting for sex, age, relevant comorbidities, co-medication, and surgery. Results: ED developed in 181 patients of the study group. The incidence density of ED was 2.53 per 1000 person-years for the HPV group and 1.51 per 1000 person-years for the non-HPV group, with an adjusted HR (95% CI) of 1.63 (1.37–1.94). In stratification analysis, adjusted HR of diabetes-, chronic obstructive pulmonary disease (COPD-), and stroke-subgroup were 2.39, 2.51, and 4.82, with significant p values for interaction, respectively. Sensitivity analysis yields consistent findings. Conclusions: The patients with HPV infection had a higher risk of subsequent ED in comparison to the non-HPV controls. The mechanism behind such association and its possible role in ED prevention deserves further study in the future.

Low androgen status inhibits erectile function by up-regulating the expression of proteins of mitochondria-associated membranes in rat corpus cavernosum

OBJECTIVE

To investigate the effect of low androgen status on mitochondria-associated membranes (MAMs) and its relationship with erectile function.

METHODS

A total of 36 eight-week-old male Sprague-Dawley rats were randomly divided into 6 groups: the control (sham-operated) group, the castration group, the castration + testosterone (cast + T) group, the control + siRNA group, the cast + siRNA group, and the cast + empty vector group. Testosterone propionate (3 mg/kg) was subcutaneously injected into the rats in the cast + T group every other day starting from the second day after the surgery. Four weeks later, lentiviral vectors carrying phosphofurin acidic cluster sorting protein 2 (PACS-2) gene-specific siRNA (1 × 10⁸ TU/ mL, 10 μL) were injected into the rats in the siRNA groups. At the 6th week of castration, the ratio of the maximum intracavernous pressure/the mean arterial pressure (ICPmax/MAP), the levels of nitric oxide (NO), endothelial nitric oxide synthase (eNOS), phospho-eNOS (p-eNOS), fatty acid-CoA ligase 4 (FACL-4), PACS-2, and inositol 1,4,5-trisphosphate receptor type 1 (IP3R1) in the penile corpus cavernosum were determined.

RESULTS

The FACL-4, PACS-2 and IP3R1 were primarily localized in the cytoplasm of endothelial cells and part of smooth muscle cells in the corpus cavernosum. The level of NO, the ratio of ICPmax/MAP, and p-eNOS/eNOS were decreased significantly in the castration group compared with the control group (P<0.01). The expressions of FACL-4, PACS-2, and IP3R1 were increased significantly in the castration group compared with the control group (P<0.01). The level of NO, the ratios of ICPmax/MAP, and the ratio of p-eNOS/eNOS were increased significantly in the cast + siRNA group compared with the castration group (P<0.01). The expressions of FACL-4 and PACS-2 were decreased significantly in the cast + siRNA group compared with the castration group (P<0.01).

CONCLUSION

Low androgen status up-regulated the expressions of patients in MAMs (FACL-4, PACS-2 and IP3R1) in the corpus cavernosum and inhibited the eNOS/NO/cGMP signaling pathway, resulting in impaired erectile function in rats. Erectile function may be improved by inhibiting the high expression of PACS-2 in the corpus cavernosum under low androgen state. This article is protected by copyright. All rights reserved.

Pharmacological Management of Pattern Hair Loss

Pattern hair loss (PHL) is a condition that worsens with time and the only way it can be slowed down is with pharmacological intervention. Pharmacological treatments for PHL, from an evidenced-based perspective with respect to safety and efficacy, are limited to only two drugs, minoxidil and finasteride. However, there are a host of drugs being used, off-label with limited evidence. This article attempts to review the literature on this topic, and the authors add to this, with their experience of over two decades on incorporating pharmacologic treatments along with hair transplantation in their management of PHL.

Short Sleep Duration and Erectile Dysfunction: A Review of the Literature

The meaning of sleep has puzzled people for millennia. In modern society, short sleep duration is becoming a global problem. It has been established that short sleep duration can increase the risk of several diseases, such as cardiovascular and metabolic diseases. Currently, a growing body of research has revealed a possible link between sleep disorders and erectile dysfunction (ED). However, the mechanisms linking short sleep duration and ED are largely unknown. Thus, we provide a review of clinical trials and animal studies. In this review, we propose putative pathways connecting short sleep duration and ED, including neuroendocrine pathways and molecular mechanisms, aiming to pave the way for future research. Meanwhile, the assessment and improvement of sleep quality should be recommended in the diagnosis and treatment of ED patients.

Potential Effect of the Circadian Clock on Erectile Dysfunction

The circadian rhythm is an internal timing system, which is generated by circadian clock genes. Because the circadian rhythm regulates numerous cellular, behavioral, and physiological processes, organisms have evolved with intrinsic biological rhythms to adapt the daily environmental changes. A variety of pathological events occur at specific times, while disturbed rhythms can lead to metabolic syndrome, vascular dysfunction, inflammatory disorders, and cancer. Therefore, the circadian clock is considered closely related to various diseases. Recently, accumulated data have shown that the penis is regulated by the circadian clock, while erectile function is impaired by an altered sleep-wake cycle. The circadian rhythm appears to be a novel therapeutic target for preventing and managing erectile dysfunction (ED), although research is still progressing. In this review, we briefly summarize the superficial interactions between the circadian clock and erectile function, while focusing on how disturbed rhythms contribute to risk factors of ED. These risk factors include NO/cGMP pathway, atherosclerosis, diabetes mellitus, lipid abnormalities, testosterone deficiency, as well as dysfunction of endothelial and smooth muscle cells. On the basis of recent findings, we discuss the potential role of the circadian clock for future therapeutic strategies on ED, although further relevant research needs to be performed.

Ex vivo Akt inhibition reverses castration induced internal pudendal artery and penile endothelial dysfunction

AIMS

Androgen deprivation therapy is a common prostate cancer treatment which causes men to have castrate levels of testosterone. Unfortunately, most testosterone deficient patients will suffer severe erectile dysfunction (ED) and have no effective ED treatment options. Testosterone deficiency causes endothelial dysfunction and impairs penile vasodilation necessary to maintain an erection. Recent evidence demonstrates testosterone activates androgen receptors (AR) and generates nitric oxide (NO) through the Akt-endothelial NO synthase (eNOS) pathway; however, it remains unknown how castration impacts this signaling pathway.

MATERIALS AND METHODS

In this study, we used a surgically castrated rat model to determine how castration impacts ex vivo internal pudendal artery (IPA) and penile relaxation through the Akt-eNOS pathway.

KEY FINDINGS

Unlike systemic vasculature, castration causes significant IPA and penis endothelial dysfunction associated with a 50% AR reduction. Though testosterone and acetylcholine (ACh) both phosphorylate Akt and eNOS, castration did not affect testosterone-mediated IPA and penile Akt or eNOS phosphorylation. Surprisingly, castration increases ACh-mediated Akt and eNOS phosphorylation but reduces the eNOS dimer to monomer ratio. Akt inhibition using 10DEBC preserves IPA eNOS dimers. Functionally, 10DEBC reverses castration induced ex vivo IPA and penile endothelial dysfunction.

SIGNIFICANCE

These data demonstrate how castration uncouples eNOS and provide a novel strategy for improving endothelial-dependent relaxation necessary for an erection. Further studies are needed to determine if Akt inhibition may treat or even prevent ED in testosterone deficient prostate cancer survivors.

Estradiol is an independent risk factor for organic erectile dysfunction in eugonadal young men

Erectile dysfunction attributable to testosterone deficiency is less common in young males, and the effect of estradiol on erectile function in eugonadal young males is unclear. We analyzed data from 195 male participants, including 143 eugonadal patients with erectile dysfunction and 52 healthy men. To distinguish psychogenic and organic erectile dysfunction, penile rigidity was measured using the nocturnal penile tumescence rigidity test. Serum levels of sexual hormones were quantified by electrochemiluminescence, and penile vascular status was assessed by penile color Doppler ultrasound. Both serum estradiol levels and the ratio of estradiol to testosterone were higher in patients with organic erectile dysfunction than in patients with psychogenic erectile dysfunction or healthy controls. Organic erectile dysfunction was negatively associated with estradiol levels and the ratio of estradiol to testosterone, and estradiol was the only significant risk factor for organic erectile dysfunction (odds ratio: 1.094; 95% confidence interval: 1.042–1.149, P = 0.000). Moreover, serum estradiol levels were negatively correlated with penile rigidity. Serum estradiol levels were higher and penile rigidity was lower in patients with venous erectile dysfunction than in patients with nonvascular erectile dysfunction. We conclude that elevated serum estradiol levels may impair erectile function and may be involved in the pathogenesis of organic erectile dysfunction in eugonadal young men.

The serum levels of testosterone in coronary artery disease patients; relation to NO, eNOS, endothelin-1, and disease severity

OBJECTIVES

The changes in testosterone level and its correlation with the endothelial nitric oxide systems balance in patients with coronary artery disease (CAD) remains uncertain. Therefore, in our study, we aimed to evaluate the levels of testosterone, endothelin-1 (ET-1), nitric oxide (NO), and endothelial NOS (eNOS) in CAD patients, and control group to find the relationship between these parameters and disease severity.

METHODS

Forty-four patients as CAD group with significant (≥50%) stenosis confirmed by angiography was included in the study, and 40 healthy men were included as the control group. According to the number of vessels obstruction, CAD severity was determined. The serum indicated parameters were assessed to discriminate between patients and controls.

RESULTS

It was found that testosterone levels in the CDA group were significantly lower than those of the control group (p<0.05). In addition, the level of ET-1 in the CAD group was higher than that in the control group, but levels of NO and eNOS in observation were significantly lower than those in the control group (p<0.05). The correlation analysis revealed that testosterone was passivity correlated with serum NO levels (r=0.550, p=0.001).

CONCLUSIONS

The current study reports that serum levels of testosterone are closely related to endothelial NO levels and might be of relevance to the pathogenesis of endothelial dysfunction and disease severity in CAD patients.

Prenatal exposure to di-n-butyl phthalate induces erectile dysfunction in male adult rats

Di-n-butyl phthalate (DBP) is a widely used plasticizer and an environmental endocrine-disrupting compound. However, whether prenatal exposure to DBP can impair erectile function remains unknown. We conducted this study to investigate the potential effects of prenatal exposure to DBP on erectile function and the underlying mechanisms. A rat model of prenatal DBP exposure (12.5, 100 or 800 mg/kg/day by gavage during gestational days 13-21) was established. Prenatal DBP exposure significantly decreased penis/body weight ratio, myelin sheath thickness of cavernosum nerves and serum testosterone level in male rats at the age of 10 weeks. Furthermore, erectile dysfunction was detected in all DBP exposure groups, which exhibited substantial increases in transforming growth factor-β1 (TGF-β1) expression and decreases in the expression of alpha smooth muscle actin (α-SMA), neuronal and endothelial nitric oxide synthase (nNOS and eNOS). Additionally, the phospho-B-cell lymphoma 2 (Bcl-2)-associated death promoter (p-Bad)/Bad and phospho-the protein kinase B (p-AKT)/AKT ratios were remarkably lower, but the Bcl-2-associated X protein (Bax)/Bcl-2 ratio and caspase-3 were higher in DBP exposure groups than in the control group. Notably, prenatal exposure to DBP increase the risk of ED in male adult rats, even taking low dose of DBP (12.5 mg/kg/day). DBP exposure causing penile fibrosis, decreased testosterone level, and endothelial dysfunction may be responsible for ED by activating Akt/Bad/Bax/caspase-3 pathway and suppressing NOS/cGMP pathway in penis.

Effect of Late Androgen Replacement Therapy on Erectile Function Through Structural Changes in Castrated Rats

Background

Because androgen replacement therapy (ART) is not performed immediately after the onset of androgen deficiency, the treatment is considered to be late.

Aim

To investigate the effects of late ART, starting 4 weeks after castration of rats, on erectile function and structural changes in the corpus cavernosum.

Methods

Rats were subjected to ART for 4 (Late-ART [4w]) or 8 (Late-ART [8w]) weeks. In either case, rats were assigned to the following groups: castrated (Cast), castrated with subcutaneous administration of testosterone (3 mg/kg/day; Cast+T), and sham (Sham). Cast + T rats received daily subcutaneous doses of testosterone starting 4 weeks after castration for 4 or 8 weeks whereas Sham and Cast rats received only the vehicle.

Outcomes

Erectile function was assessed by evaluating intracavernosal pressure (ICP) and mean arterial pressure (MAP) after electrical stimulation of the cavernous nerve, corporal veno-occlusive function using dynamic infusion cavernosometry, and histology using Masson's trichrome staining.

Results

No increase in the ICP was observed in Cast+T rats in the Late-ART (4w) group (0.47 ± 0.02, P > .05), whereas, in Cast+T rats in the Late-ART (8w) group, there was a significant increase in the ICP/MAP ratio (0.60 ± 0.02, P < .05), drop rate, and smooth muscle/collagen ratio.

Clinical Translation

The present study provides scientific evidence for the effect of late ART on erectile function.

Strengths and Limitations

This study provides insights into the influence of late ART on erectile function through improvements in the structure of corpus cavernosum. The major limitation of this study is the difference in the time required for healing between the humans and rats, which might have a bearing on the translational relevenace of the results.

Conclusions

Late ART could improve erectile function. However, as improvement requires a considerable time period, it is necessary to persist with therapy patiently for optimal results.

Kataoka T, Hotta Y, Yamamoto Y, et al. Effect of Late Androgen Replacement Therapy on Erectile Function Through Structural Changes in Castrated Rats. Sex Med 2021;XX:XX–XXX.

Risk of osteoporosis in patients with erectile dysfunction: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Erectile dysfunction (ED) and osteoporosis are both common health problems and have similar risk factors. Recent studies have found that people with ED have a higher risk of osteoporosis.We aimed to systematically assess osteoporosis risk in patients with ED.

METHODS

A systematically research was carried out in Medline via PubMed, Cochrane Library, EMBASE, and Web of Science up to June 4, 2020, to identify articles related to ED and osteoporosis. The 2 researchers independently reviewed the literature, extracted the data, and evaluated the quality of the literature. All analyses were done using RevMan5.3 and Stata14.

RESULTS

A total of 4 studies involving 22,312 participants were included. The meta-analysis results showed that the risk of osteoporosis in the ED group was significantly higher than that in the non-ED group [odds ratio (OR) = 2.66, 95% confidence interval (95% CI) 1.42 to 4.98, P = .002, I2 = 68%]. Interestingly, compared with older participants, the increased risk of osteoporosis in ED patients seemed to be more pronounced in younger participants. Despite the lack of data for meta-analysis, more than half of the literature mentioned this tendency. We found the source of heterogeneity through sensitivity analysis, and there was no significant effect on the results before and after the removal of this literature, indicating that our results were robust. No obvious publication bias was found through Egger method (P = .672).

CONCLUSION

People with ED have a higher risk of osteoporosis, especially among younger males. Because the assessment of osteoporosis is economical and noninvasive, ED patients should be evaluated by bone mineral density or men with osteoporosis should be further assessed for erectile function.

Role of Glucose-Lowering Medications in Erectile Dysfunction

Erectile dysfunction (ED) is a long-term complication of type 2 diabetes (T2D) widely known to affect the quality of life. Several aspects of altered metabolism in individuals with T2D may help to compromise the penile vasculature structure and functions, thus exacerbating the imbalance between smooth muscle contractility and relaxation. Among these, advanced glycation end-products and reactive oxygen species derived from a hyperglycaemic state are known to accelerate endothelial dysfunction by lowering nitric oxide bioavailability, the essential stimulus of relaxation. Although several studies have explained the pathogenetic mechanisms involved in the generation of erectile failure, few studies to date have described the efficacy of glucose-lowering medications in the restoration of normal sexual activity. Herein, we will present current knowledge about the main starters of the pathophysiology of diabetic ED and explore the role of different anti-diabetes therapies in the potential remission of ED, highlighting specific pathways whose activation or inhibition could be fundamental for sexual care in a diabetes setting.

Estradiol-Testosterone Imbalance Is Associated with Erectile Dysfunction in Patients with Klinefelter Syndrome

Erectile dysfunction (ED) is a frequent sexual disorder in adult men. Klinefelter syndrome (KS) is the most common sex chromosomal disorder and a frequent cause of male hypogonadism. Psychological and cognitive aspects are quite typical in KS and have been linked to ED, while the role of testosterone (T) levels in sexual function of KS subjects has not been fully elucidated. The purpose of the present study is to investigate the role of hormonal disturbances in erectile function of subjects with KS. We conducted a retrospective study involving 52 Klinefelter patients newly diagnosed who never received androgen replacing therapy. All the subjects underwent medical history, accurate physical examination, and blood tests. The International Index of Erectile Function questionnaire (IIEF-EF) score correlated negatively with estradiol/testosterone ratio (E2/T); this correlation remained statistically significant after correction for age (ρ −0.320 p = 0.018). A multiple linear regression analysis identified age and E2/T as the main predictors of IIEF-EF score (R2 0.169 F = 3.848 p = 0.008). Our findings corroborate previous KS data obtained in the general population showing an association between higher E2/T ratio and impaired erectile function. Larger studies are required to better elucidate the pathophysiology of ED in patients with KS.

Low androgen status inhibits erectile function by increasing pyroptosis in rat corpus cavernosum

BACKGROUND

The mechanism of erectile dysfunction (ED) caused by low androgen status is not fully understood.

OBJECTIVES

To investigate whether low androgen status inhibits erectile function of rats by inducing pyroptosis in the corpus cavernosum (CC).

MATERIALS AND METHODS

Thirty-six eight-weeks-old healthy male Sprague-Dawley rats were equally divided into six groups: sham-operated group (4w sham, 8w sham), castration group (4w cast, 8w cast), and castration + testosterone (T) group (4w cast + T, 8w cast + T). The rats in castration + T groups were injected with testosterone propionate subcutaneously every other day. After 4 and 8 weeks, the ratio of maximum intracavernous pressure (ICPmax)/mean arterial pressure (MAP), the level of serum T, the concentration of nitric oxide (NO) and interleukin-1β (IL-1β), the expression of NOD-like receptor pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC), Caspase-1 p20, gasdermin D-N (GSDMD-N), transforming growth factor β1 (TGF-β1), collagen-I, and collagen-III, the ratio of smooth muscle/collagen (SM/C), and the proportion of pyroptotic cells in the CC were analyzed.

RESULTS

The ratio of ICPmax/MAP (3/5 V) and SM/C, the level of NO and serum T was significantly decreased in castration groups when compared to other groups (p < 0.01). NLRP3, ASC, Caspase-1, and GSDMD were mainly expressed in the cytoplasm of smooth muscle cells (SMCs) and endothelial cells (ECs) in the CC. The expression of NLRP3, ASC, Caspase-1p20, GSDMD-N, IL-1β, TGF-β1, collagen-I, and collagen-III was significantly increased in castration groups when compared with other groups (p < 0.01). The proportion of pyroptotic cells in the CC was increased significantly in castration groups when compared with other groups (p < 0.05).

DISCUSSION AND CONCLUSION

Low androgen status inhibits erectile function of rats by promoting CC fibrosis and reducing NO synthesis through pyroptosis of SMCs and ECs in the CC.

Serum folic acid levels and erectile dysfunction: A meta-analysis and systematic review

The aim of this study was to assess the relationship between serum folic acid (FA) levels and erectile dysfunction (ED) through a meta-analysis. A research was conducted in MEDLINE via PubMed, Cochrane Library, EMBASE and Web of Science up to 22 November 2020 to identify studies related to FA and ED. Two authors independently screened the literature, evaluated methodological quality and extracted the data. We used RevMan5.3 and STATA 14.0 for meta-analysis. A total of six studies including 1,842 participants were included, and the results showed that the FA levels in the non-ED group were significantly higher than those in the ED group (MD = 3.37, 95% CI 1.49-5.52, p = 0.004). Subgroup analysis indicated that with the increase in ED severity, the difference in FA levels between groups was more obvious (MD: 1.99 vs. 4.63 vs. 5.63). The differences in FA levels between groups seem more significant in the younger group (MD = 4.87, 95% CI 2.58-6.89, p < 0.001) than in the older group (MD = 3.15, 95% CI 2.21-4.08, p < 0.001). In conclusion, FA deficiency is closely related to ED, and the degree of FA deficiency may reflect the severity of ED. In addition, the association seems to be more pronounced in the younger group.

Testosterone deficiency in men receiving immunotherapy for malignant melanoma

Immunotherapy has been established as a standard of care for patients with malignant melanoma, however, the long-term side-effects of immunotherapy are still emerging. Studies over the last decade have documented increasing reports of endocrine dysfunction following the initiation of immunotherapy. Our study aimed to detect the proportion of men who have low testosterone before, during, and or/after receiving immunotherapy for malignant melanoma, and to determine the proportion of men who receive testosterone replacement therapy after detection of low testosterone. We performed retrospective chart review of patients with malignant melanoma treated with immunotherapy. Low testosterone was identified in 34 out of 49 patients at some point during their treatment with immunotherapy. Despite low testosterone levels in two-thirds of patients, only three patients were treated with testosterone replacement therapy. In addition to laboratory evidence of low testosterone, patients were also symptomatic as 43 out of 49 patients reported fatigue to their providers. Four patients developed hypophysitis and subsequent hypopituitarism, all of whom were receiving Ipilimumab. We conclude that patients with stage 3 or 4 melanoma treated with immunotherapy appear to be at an increased risk of developing testosterone deficiency during their treatment.

High efficacy, rapid onset nanobiolosomes of sildenafil as a topical therapy for erectile dysfunction in aged rats

Developing topical sildenafil for local treatment of erectile dysfunction has been of great interest in pharmaceutical research. Sildenafil citrate (SC) exhibited a well-documented success for treatment of several types of erectile dysfunction. However, its oral use is limited by serious adverse effects, poor bioavailability, delayed onset, and drug-drug interactions. This work is the first to design and assess sildenafil-loaded bilosomes for topical local treatment of erectile dysfunction. Different sildenafil-loaded bilosomes were prepared and characterized. Permeability of selected formulations was conducted through full-thickness human skin. Optimized bilosomes integrating sodium tauroglycocholate (STGC) showed spherical shape with good particle size (133 nm), high zeta potential (-53.6 mV) and high entrapment efficiency (87.45%). Ex-vivo permeability study revealed that about 39% of the applied dose permeated within 15 min. Furthermore, in-vivo appraisal of therapeutic efficacy was performed using aged male Sprague-Dawley rats. After single application of 2 mg/kg sildenafil loaded in STGC-bilosomes, behavioral and biochemical evaluation was carried out. Behavioral assessment recorded an increased rats' potency manifested as 2 folds increase in intromission frequency and intromission ratio compared to untreated group. That was accompanied by significant increase in cGMP concentration in corpora cavernosa (P < 0.0001) confirming increased potency. In conclusion, STGC-bilosomes could provide topical treatment of impotence with 20% of the oral dose and fast onset of action (10 min).

Estradiol correlates with erectile dysfunction and its severity in type 2 diabetic patients

AIMS

Erectile dysfunction (ED) is a frequent microvascular complication of type 2 diabetes mellitus (T2DM). Hormonal derangements such as hypogonadism and hyperestrogenism are common in T2DM. Our aim was to investigate the relationship between estrogens and ED in diabetic patients.

METHODS

We performed a retrospective study on 57 patients with T2DM suffering from ED. ED was assessed with the International Index of Erectile Function questionnaire (IIEF-5) and penile color-doppler ultrasound (PCDU). Blood tests included glycated hemoglobin, lipid profile, total testosterone (T), and estradiol (E2).

RESULTS

E2 was negatively correlated with IIEF-5 score after correction for age, diabetes duration, BMI, HbA1c, LDL- and HDL-cholesterol, T and PSA (r = -0.457, p < 0.01). Patients in the higher E2 quartile, had statistically higher probability of severe ED (61.5%). In the same patients, the PCDU demonstrated a statistically longer Acceleration Time (120.0 ± 24.5, p = 0.048) indicating an impaired arterial flow.

CONCLUSIONS

In diabetic patients, higher E2 is associated with worse erectile function and impaired cavernous arterial flow. Diabetic patients with high E2 are more prone to severe ED. It could be suggested to include estradiol measurement in the hormonal assessment of ED in patients with T2DM.

Research progress on the relationship between sex hormone-binding globulin and male reproductive system diseases

Sex hormone-binding globulin, also known as testosterone-estradiol-binding globulin, is a multifunctional protein synthesised by hepatocytes. Sex hormone-binding globulin specifically binds and transports sex hormones to regulate plasma bioactive sex hormone levels and affects their bioavailability. As male sex hormone expression is dominated by testosterone, the binding of sex hormone-binding globulin with testosterone leads to the reduction in bioavailable testosterone, which cannot fulfil its physiological roles, thereby resulting in male infertility, erectile and gonadal dysfunction, prostate cancer and other male reproductive system diseases. Sex hormone-binding globulin may be involved in the pathogenesis of male reproductive system diseases, seriously affecting the quality of life of men. In this article, we review the association between sex hormone-binding globulin and male reproductive system diseases.

Early Effect of Metabolic Surgery on Erectile Function and Ejaculation: a Pilot Study of Obese Men with Type 2 Diabetes Mellitus

PURPOSE

Majority of men with type 2 diabetes mellitus (T2DM) have been reported to experience erectile dysfunction (ED) in a lifetime. The aim of our study was to prospectively evaluate the postoperative condition of ED and premature ejaculation (PE) in men who underwent metabolic surgery for the treatment of T2DM.

MATERIALS AND METHODS

A total of 36 sexually active male individuals with T2DM who were applied for metabolic surgery were given two different questionnaire forms prior to and 6 months after the surgery. Patients filled the International Index of Erectile Function (IIEF) and the Premature Ejaculation Profile (PEP) questionnaires before and 6 months after the surgery. The BMI, fasting blood glucose (FBG), and glycated hemoglobin (HbA1c) concentrations were also measured prior to the surgery and on follow-up points of postoperative first, third, and sixth months.

RESULTS

Erectile function (EF) and overall satisfaction domains of the IIEF questionnaire increased significantly after the surgery in the patient groups irrespective of the previous ED severity (p < 0.001). There were significant improvements of the PEP interpersonal difficulty related to ejaculation score and HbA1c levels in the severe/moderate EF group and IIEF EF, PEP interpersonal difficulty related to ejaculation domains, and HbA1c levels of mild to moderate/mild/no ED group after the metabolic surgery.

CONCLUSION

Metabolic surgery could improve erectile and ejaculatory function scores of obese patients with T2DM.

Association of erectile dysfunction and type II diabetes mellitus at a tertiary care centre of south India

BACKGROUND AND AIMS

Erectile Dysfunction (ED) is more common in diabetic men and, unfortunately, occurs at an earlier age in diabetic patients when compared with the general population. The study aims to evaluate the independent predictors of ED in adult men with type 2 diabetes mellitus (DM) at a tertiary care center of South India.

METHODS

A total of 720 men aged 30-70 years who had been diagnosed with type 2 DM were enrolled for the study from January 2017 to January 2020 from the outpatient diabetes clinic of the Hospital. All patients completed the abridged version of the International Index of Erectile Function (IIEF-5) questionnaire.

RESULTS

The mean age of the patients was (58.4 ± 7.8 years). 68.6% of subjects had varying degrees of erectile dysfunction, of which 54.6% had moderate to severe ED. 55.8% had poor glycemic control (HbA1c ≥ 7%). Subjects with ED had a longer duration of DM than those without ED (mean DM duration was 8.1 ± 4.9 years versus 4.4 ± 3.5 years; p < 0.001). Longer duration of DM, poor glycemic control, hypertension, peripheral arterial disease, testosterone deficiency were all independent predictors ED (p < 0.05).

CONCLUSIONS

A high incidence of erectile dysfunction was observed in type 2 DM patients attending the diabetic clinic, and over half of the people affected were of moderate-to-severe in intensity. Poor glycemic control, testosterone deficiency, peripheral arterial disease were the modifiable risk factors for ED in diabetic subjects. At the same time, a longer duration of type 2 DM was noticed as a glaring non-modifiable risk factor, according to our study.

Long-term treatment with testosterone undecanoate injections in men with hypogonadism alleviates erectile dysfunction and reduces risk of major adverse cardiovascular events, prostate cancer, and mortality

Objective: The association between erectile dysfunction (ED), hypogonadism, cardiovascular disease, and type 2 diabetes is well documented, but long-term data are limited. The aim of this study is to investigate effects of long-term testosterone therapy (TTh) with testosterone undecanoate in men with hypogonadism and ED.Patients and methods: Observational, prospective registry of 805 hypogonadal men with different degrees of ED, evaluated by the International Index of Erectile Function - Erectile Function Domain. Four hundred and twelve patients underwent TTh, 393 patients served as controls, with an observation period up to 12 years.Results: TTh led to substantial and sustained reduction of ED; improvement in erectile function was significant for each successive year until year 9. This was accompanied by improvements in cardiometabolic risk factors and urinary function throughout the 12-year follow-up period. Benefits of TTh were stronger for patients with moderate/severe ED than for patients with no/minor ED. Incidence of prostate cancer, major adverse cardiovascular events, and mortality were significantly lower in men on TTh compared with untreated men.Conclusion: Long-term TTh for up to 12 years alleviates ED, improves cardiometabolic risk factors, and reduces prostate cancer. Patients must stay on TTh consistently for a long time to achieve maximum benefits of TTh.

Effect of estradiol on penile erection: a cross-sectional study

Background

Past studies have shown that elevated estradiol levels could inhibit penile erection, but the relationship between estradiol and erection of the penile tip or base has not been extensively researched.

Methods

We therefore investigated estradiol's effects on the erection of the penile tip and base, with a cross-sectional study of 135 patients with erectile dysfunction (ED), based on scores of ≤21 according to the International Index of Erectile Function-5. All patients were tested for nocturnal penile tumescence, blood pressure (BP), serum glucose, total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL), progesterone (P), estradiol (E), and testosterone (T). Univariate and multivariate analyses were used to assess associations between estradiol levels and erection at the penile tip and base.

Results

We found no obvious relationship between erection time at penile tip and estradiol levels but did observe a negative correlation between base erection time and estradiol level [hazard ratio (HR): ‒0.11; 95% CI: ‒0.80-1.72]. With increasing estradiol concentration, multivariate analysis showed an obvious reduction in base erection time among patients with normal Rigiscan results (HR: ‒0.31; 95% CI: ‒1.63-1.29) (P<0.05) as estradiol concentration increased.

Conclusions

Our data indicate that estradiol inhibits penile erection, particularly at the penile base. Also, when the effective erection time of the penile base lasts longer than 10 min, estradiol has a more obvious inhibitory effect on penile base erection.

Randomized controlled trials - mechanistic studies of testosterone and the cardiovascular system

Testosterone deficiency is common in men with cardiovascular disease (CVD), and randomized placebo-controlled trials (RCTs) have reported beneficial effects of testosterone therapy on exercise-induced cardiac ischemia in chronic stable angina, functional exercise capacity, maximum oxygen consumption during exercise (VO_2max) and muscle strength in chronic heart failure (CHF), shortening of the Q-T interval, and improvement of some cardiovascular risk factors. Testosterone deficiency is associated with an adverse CV risk profile and mortality. Clinical and scientific studies have provided mechanistic evidence to support and explain the findings of the RCTs. Testosterone is a rapid-onset arterial vasodilator within the coronary circulation and other vascular beds including the pulmonary vasculature and can reduce the overall peripheral systemic vascular resistance. Evidence has demonstrated that testosterone mediates this effect on vascular reactivity through calcium channel blockade (L-calcium channel) and stimulates potassium channel opening by direct nongenomic mechanisms. Testosterone also stimulates repolarization of cardiac myocytes by stimulating the ultra-rapid potassium channel-operated current. Testosterone improves cardiac output, functional exercise capacity, VO_2max and vagally mediated arterial baroreceptor cardiac reflex sensitivity in CHF, and other mechanisms. Independent of the benefit of testosterone on cardiac function, testosterone substitution may also increase skeletal muscle glucose metabolism and enhance muscular strength, both factors that could contribute to the improvement in functional exercise capacity may include improved glucose metabolism and muscle strength. Testosterone improves metabolic CV risk factors including body composition, insulin resistance, and hypercholesterolemia by improving both glucose utilization and lipid metabolism by a combination of genomic and nongenomic actions of glucose uptake and utilization expression of the insulin receptor, glucose transporters, and expression on regulatory enzymes of key metabolic pathways. The effect on high-density lipoprotein-cholesterol (HDL-C) differs between studies in that it has been found to fall, rise, or have no change in levels. Testosterone replacement can suppress the levels of circulating pro-inflammatory cytokines and stimulate the production of interleukin-10 (IL-10) which has anti-inflammatory and anti-atherogenic actions in men with CVD. No effect on C-reactive protein has been detected. No adverse effects on clotting factors have been detected. RCTs have not clearly demonstrated any significant evidence that testosterone improves or adversely affects the surrogate markers of atherosclerosis such as reduction in carotid intima thickness or coronary calcium deposition. Any effect of testosterone on prevention or amelioration of atherosclerosis is likely to occur over years as shown in statin therapy trials and not months as used in testosterone RCTs. The weight of evidence from long-term epidemiological studies supports a protective effect as evidenced by a reduction in major adverse CV events (MACEs) and mortality in studies which have treated men with testosterone deficiency. No RCT where testosterone has been replaced to the normal healthy range has reported a significant benefit or adverse effect on MACE nor has any recent meta-analysis.

Congenital absence of the penis (aphallia): A rare case report

RATIONALE

Absence of the penis, known as aphallia, is a very rare congenital anomaly. It is believed to be a result of either the absence of the genital tubercle or its failure to fully develop and is associated with the level of hormones and chromosomal rearrangements. The failure of the genital tubercle influences the development of the penis and partly depends upon testosterone secreted by Leydig cells of the testis. Chromosomal polymorphisms may affect the functions of protection and regulation, potentially leading to susceptibility to congenital diseases. Herein, an extremely rare case of a congenital absence of the penis is described.

PATIENT CONCERNS

A 3-month-old was brought to the OPD by his parents with complaints of absence of penis since birth and urine being passed rectally. When he was born, he was registered as a boy because his chromosomes were 46XY but with 9qh+. Local examination revealed the total absence of the penis. The scrotum was well developed. The testes were palpable bilaterally. The anal opening was located normally. No urethral orifice could be identified. However, his parents had not yet decided whether to accept treatment. The child has been lost to follow up.

DIAGNOSIS

Congenital absence of the penis (aphallia) (46 XY normal male karyotype).

INTERVENTIONS

We explained the nature of the abnormality and management options to the parents. However, it was much regretted that the patient was too young to make a decision and that his parents had not made a decision yet. They left without any further contact.

OUTCOME

Because the parents left our hospital without any contact, it has not been possible to develop a follow-up plan.

LESSONS

In consideration of the rarity and devastating psychosocial consequences of this case, we accordingly call for active cooperation with doctors to minimize the negative impact of this malformation. Early assignment of gender avoids confusion and contradiction. Parental confidence solidifies the child's own confidence in his or her gender.

Androgen Deficiency and Phosphodiesterase Type 5 Expression Changes in Aging Male: Therapeutic Implications

The age-related decline of serum T occurs in ~20-30% of adult men and it is today defined as late-onset hypogonadism (LOH). In the elderly, such decline becomes more prevalent (up to 60%) and shows-up with erectile dysfunction (ED) and hypoactive sexual desire. A large body of experimental evidences have shown that the combination of T replacement therapy (TRT) and phosphodiesterase type 5 inhibitors (PDE5i) is, usually, effective in restoring erectile function in patients with LOH and ED who have not responded to monotherapy for sexual disturbances. In fact, PDE5is potentiate the action of nitric oxide (NO) produced by endothelial cells, resulting in a vasodilator effect, while T facilitates PDE5i effects by increasing the expression of PDE5 in corpora cavernosa. Meta-analytic data have recognized to PDE5i a protective role on the cardiovascular health in patients with decreased left ventricular ejection fraction. In addition, several studies have shown pleiotropic beneficial effects of these drugs throughout the body (i.e., on bones, urogenital tract and cerebral, metabolic, and cardiovascular levels). TRT itself is able to decrease endothelial dysfunction, oxidative stress and inflammation, thus lowering the cardiovascular risk. Furthermore, untreated hypogonadism could be the cause of PDE5i ineffectiveness especially in the elderly. For these reasons, aging men complaining ED who have LOH should undergo TRT before or at the moment when PDE5i treatment is started.

Histomorphological changes in the common carotid artery of the male rat in induced hypogonadism

The role of androgens in the development of cardiovascular diseases remains controversial. The current study therefore sought to determine the changes in the histomorphology of the common carotid artery of the male rat in orchidectomy-induced hypogonadism. Twenty-two Rattus norvegicus male rats aged 2 months were used. The rats were randomly assigned into baseline (n=4), experimental (n=9), and control (n=9) groups. Hypogonadism was surgically induced in the experimental group by bilateral orchiectomy under local anesthesia. At experiment weeks 3, 6, and 9, three rats from each group (experimental and control) were euthanized, their common carotid artery harvested, and routine processing was done for paraffin embedding, sectioning, and staining. The photomicrographs were taken using a digital photomicroscope for morphometric analysis. Orchidectomy resulted in the development of vascular fibrosis, with a significant increase in collagen fiber density and decrease in smooth muscle and elastic fiber density. Moreover, there was development of intimal hyperplasia, with fragmentation of medial elastic lamellae in the common carotid artery of the castrated rats. Orchidectomy induces adverse changes in structure of the common carotid artery of the male rat. These changes may impair vascular function, therefore constituting a possible structural basis for the higher incidences of cardiovascular diseases observed in hypogonadism.