Differential Effects of Testosterone and Estradiol on Clitoral Function: An Experimental Study in Rats

Hypoactive sexual desire disorder in women: new possibilities to ensure better understanding, diagnosis, and response to treatment

BACKGROUND

Hypoactive Sexual Desire Disorder (HSDD) is a frequent sex-related problem in women; however, a specific tool to characterize HSDD subtypes based on sexual inhibitory and excitatory factors is still lacking.

AIM

(1) To find a cutoff value in Sexual Inhibition Scale (SIS)/Sexual Excitation Scale (SES) scores predicting a diagnosis of HSDD in women consulting for sexual symptoms, (2) to explore the sexual inhibitory and excitatory profiles in women referred to a clinic for female sexual dysfunction by stratifying the sample according to the newfound cutoffs, and (3) to identify biopsychosocial factors significantly associated with the 2 profiles.

METHODS

An overall 133 women consulting for sexual symptoms were retrospectively evaluated for clinical, biochemical, and psychosexologic data collected at the first visit. A subgroup of 55 women treated with transdermal testosterone was retrospectively analyzed at baseline and the 6-month visit.

OUTCOMES

Patients underwent physical and laboratory examinations and completed the SIS/SES, Female Sexual Function Index, Female Sexual Distress Scale-Revised, Emotional Eating Scale, and Middlesex Hospital Questionnaire.

RESULTS

Specific cutoffs for SIS1 (≥32.5; indicating threat of performance failure) and SES (≤46.5) predicted HSDD diagnosis with an accuracy of 66.4% (P = .002) and 68.7% (P < .0001), respectively. Patients with impaired SIS1 scores showed higher distress and psychopathologic symptoms, while those with impaired SES scores demonstrated lower desire and arousal and a negative association with some metabolic and hormonal parameters. SES score also showed a significant predictive value on testosterone treatment efficacy for HSDD.

CLINICAL TRANSLATION

A better characterization of HSDD would enable individualized treatment based on the main underlying etiologies.

STRENGTHS AND LIMITATIONS

Limitations of the study include the small sample size and cross-sectional retrospective design, with the choice of treatment for HSDD limited to transdermal testosterone. Strengths comprise the thorough and multifactorial evaluation of every aspect potentially affecting inhibitory and excitatory components of sexual desire.

CONCLUSION

Validated cutoffs of SIS/SES scores could allow deep characterization of women diagnosed with HSDD, thus ensuring better tailoring of therapy and prediction of the probability of response to specific treatments.

Counseling Women About Sexual Health Effects of Contraceptives

Background: Choosing a contraceptive method is a pivotal decision for patients, whereas health care professionals (HCPs) face challenges in providing suitable recommendations. Adverse sexual effects often lead to dissatisfaction and discontinuation of contraceptives, underscoring the importance of thorough counseling and shared decision making between HCPs and patients. Objective: This article aims to investigate the relationship between contraceptive methods and female sexual function through a comprehensive review of available literature, emphasizing the importance of considering sexual health in contraceptive prescription and management. Methods: A systematic analysis of existing literature, incorporating studies utilizing validated sexual health questionnaires, was conducted to elucidate the intricate interplay between contraceptives and female sexual function. Results: The review encompasses various contraceptive methods, including combined hormonal contraceptives, progestin-only pills, depot medroxyprogesterone acetate, subdermal contraceptive implants, hormonal intrauterine devices, permanent sterilization, and barrier methods. Insights gleaned from the analysis shed light on the impact of these methods on female sexual health. Conclusion: Comprehensive understanding of the effects of contraceptives on female sexual function is crucial for both HCPs and patients. By integrating sexual health considerations into contraceptive surveillance, compliance can be improved, contraceptive efficacy optimized, and the risk of unwanted pregnancies minimized. This review underscores the significance of tailored counseling and shared decision making in contraceptive management, particularly for cisgender women.

Low prolactin level identifies hypoactive sexual desire disorder women with a reduced inhibition profile

PURPOSE

Data on the role of prolactin (PRL) in the physiologic range in the female sexual response are scanty. We aimed at investigating the association between PRL and sexual function as assessed by the Female Sexual Function Index (FSFI). We explored the presence of a cut-off level of PRL able to identify Hypoactive Sexual Desire Disorder (HSDD).

METHODS

277 pre- and post-menopausal women consulting for Female Sexual Dysfunction (FSD) and sexually active were enrolled in an observational, retrospective study. 42 women were used as no-FSD controls. A clinical, biochemical and psychosexual evaluation was performed. The main outcome measures were: FSFI, Female Sexual Distress Scale-Revised, Middlesex Hospital Questionnaire and Sexual excitation/sexual inhibition scale (SIS/SES).

RESULTS

Normo-PRL FSD women (n = 264) showed lower FSFI Desire score than controls (n = 42), and higher than hyper-PRL FSD women (n = 13). These differences emerged both in pre-menopausal and post-menopausal subjects. In the normo-PRL FSD group, those with PRL in the higher quintile reported higher FSFI Desire scores than those with PRL in the lowest quintile. Women with HSDD presented a lower PRL level than those without (p = 0.032). A ROC curve analysis for PRL showed an accuracy of 0.610 ± 0.044 (p = 0.014) in predicting HSDD. With a threshold of < 9.83 μg/L, sensitivity and specificity for HSDD were 63% and 56%, respectively. Subjects with PRL < 9.83 μg/L also reported lower sexual inhibition (p = 0.006) and lower cortisol levels (p = 0.003) than those with PRL >  = 9.83 μg/L.

CONCLUSIONS

Hyper-PRL is associated with low desire; however, among normo-PRL FSD women, those with the lowest levels demonstrated a poorer desire than those with the highest levels. PRL < 9.83 μg/L predicted HSDD and a lower sexual inhibitory trait.

Methamphetamine-induced vaginal lubrication in rats

BACKGROUND

Based on previous studies of vaginal lubrication as well as our own previously reported interview study of women who self-reported methamphetamine (meth)-induced vaginal lubrication, in the current study we sought to determine the potential dose-response relationship leading to meth-induced vaginal lubrication. We also developed an animal model to study the reported effects and examine potential mechanisms mediating this phenomenon.

AIM

We sought to characterize the effects of meth on vaginal lubrication in an animal model with the aim of providing a potential framework for new mechanisms that incorporate novel therapeutic agents for the treatment of vaginal dryness.

METHODS

Vaginal lubrication was measured via insertion of a preweighed, cotton-tipped swab into the vaginal canal of anesthetized rats following treatment with various doses of intravenous (IV) meth, up to 0.96 mg/kg, and after additional pharmacological manipulations, including administration of a nitric oxide synthase inhibitor and an estrogen receptor antagonist. Plasma signaling molecules, including estradiol, progesterone, testosterone, nitric oxide, and vasoactive intestinal polypeptide, were measured immediately before and at 9 time points after IV meth administration. Blood was collected via a previously implanted chronic indwelling jugular catheter and analyzed by use of commercially available kits per the manufacturer's instructions.

OUTCOMES

Outcomes for this study include the measurement of vaginal lubrication in anesthetized rats following various pharmacological manipulations and plasma levels of various signaling molecules.

RESULTS

Meth dose-dependently increased vaginal lubrication in anesthetized female rats. Meth significantly increased plasma levels compared to baseline of estradiol (2 and 15 minutes after meth infusion) as well as progesterone, testosterone, and nitric oxide (10 minutes after meth infusion). Also, vasoactive intestinal polypeptide decreased significantly compared to baseline for 45 minutes following meth infusion. Our data further suggest that nitric oxide, but not estradiol, is critical in the production of vaginal secretions in response to meth.

CLINICAL IMPLICATIONS

This study has far-reaching implications for women who are suffering from vaginal dryness and for whom estrogen therapy is unsuccessful, as the investigation has demonstrated that meth presents a novel mechanism for producing vaginal lubrication that can be targeted pharmacologically.

STRENGTHS AND LIMITATIONS

This study is, to our knowledge, the first performed to measure the physiological sexual effects of meth in an animal model. Animals were anesthetized when they were administered meth. In an ideal situation, animals would be self-administering the drug to recapitulate better the contingent nature of drug taking; however, this method was not feasible for the study reported here.

CONCLUSION

Methamphetamine increases vaginal lubrication in female rats through a nitric oxide-dependent mechanism.

Effect of folic acid on the sexual function of postmenopausal women: a triple-blind randomized controlled trial

BACKGROUND

There are reports of sexual dysfunction in postmenopausal women, and several treatment recommendations are available.

AIM

To investigate the effect of folic acid on postmenopausal women's sexual function.

METHODS

This triple-blind randomized controlled trial was conducted in Tehran, Iran, in 2020. A sample of 100 postmenopausal women was recruited from comprehensive health centers affiliated with the Shahid Beheshti University of Medical Sciences. Eligible women were randomly assigned to receive folic acid (5 mg) or placebo on an empty stomach every day for 8 weeks. Women were assessed at 3 time points: baseline and 4 and 8 weeks after the intervention.

OUTCOME

Sexual function was the main outcome, as measured by the Female Sexual Function Index.

RESULTS

The mean ± SD age of participants in the folic acid and placebo groups was 53.2 ± 3.84 and 54.4 ± 4.05 years, respectively (P = .609). The results obtained from mixed effects analysis of variance revealed a statistically significant difference between baseline and posttreatment scores and the interaction between time and group for desire, orgasm, satisfaction, arousal, pain, and total sexual function score, with the folic acid group improving more than control group. Lubrication was the only domain that showed no significant difference for the interaction between time and group.

CLINICAL IMPLICATIONS

Folic acid may beneficially affect sexual function in postmenopausal women.

STRENGTHS AND LIMITATIONS

Strengths include the novelty of the subject, the triple-blind design, the block randomization, the administration of a standard scale for sexual function (Female Sexual Function Index), and the affordability and availability of folic acid. This study was conducted with a small sample size and short follow-up time; therefore, interpretation of the results requires great caution.

CONCLUSION

The findings suggest that folic acid possibly improves sexual function in postmenopausal women. Larger studies are needed to confirm the findings.

TRIAL REGISTRATION

IRCT20150128020854N8; August 2, 2020. Iranian Registry of Clinical Trials; https://en.irct.ir/user/trial/48920/view.

Aging effects in the extracellular matrix of the clitoris: A scanning electron microscopic analysis

OBJECTIVE OF THE STUDY

The present work aims to observe the clitoris' extracellular matrix in young and old women with a scanning electron microscope.

MATERIALS AND METHODS

After approval of the local research ethics committee, samples of the clitoris body were obtained from cadavers of women between 20 and 40 old (G1) and from cadavers over the age of 60 (G2). The samples were decellularized with NaOH to maintain the extracellular matrix framework, submitted to silver sputter coating, and observed under a scanning electron microscope.

RESULTS

The mean age of the cadavers in G1 was 28 years old and 75±6 years old in G2. The groups were composed of 10 cadavers each. It was observed that the collagen was arranged in a disorganized fashion in the samples from the G2 in several regions. There was also a decrease in elastic fibers that anchored the collagen in these samples. The concentration of collagen showed an increase in the older samples in comparison to the G1 samples. Conclusions Female sexual dysfunction is a condition prevalent in a significantly large portion of women and it is more common in elderly women. It is known that the tumescence mechanism requires integrity of the extracellular matrix. The changes observed herein may alter the function of the organ and are similar to observations in studies of men with erectile dysfunction.

CONCLUSION

Female sexual dysfunction is a condition prevalent in a significantly large portion of women and it is more common in elderly women. It is known that the tumescence mechanism requires integrity of the extracellular matrix. The changes observed herein may alter the function of the organ and are similar to observations in studies of men with erectile dysfunction. .

Climacteric symptoms, age, and sense of coherence are associated with sexual function scores in women after menopause

BACKGROUND

Postmenopausal sexual function presupposes the integration of hormonal, neural, and vascular interactions and is subject to optimal crosstalk among psychological, interpersonal, cultural, and environmental factors. Sense of coherence (SOC) reflects a person's ability to cope with stressors and may influence the occurrence of menopausal symptoms and sexual dysfunction.

AIM

To investigate the association of severity of climacteric symptoms, cardiometabolic risk factors, and SOC with sexual function in postmenopausal women.

METHODS

Overall 281 sexually active postmenopausal women without significant psychopathology or cardiovascular disease attending the Menopause Unit of Aretaieion Hospital were evaluated by the Female Sexual Function Index (FSFI), Greene Climacteric Scale, Beck Depression Scale, and Sense of Coherence Scale. Hormonal and biochemical parameters and cardiometabolic risk factors were evaluated. FSFI scores <26.5 were considered pathologic.

OUTCOMES

Total and subdomain scores of sexual response were determined.

RESULTS

Pathologic FSFI scores were found in 79.7% of the sample. Linear models of multivariable regression analysis showed that FSFI scores were associated with (1) Beck scores (b  = -0.200; 95% CI, -0.472 to -0.073, P = .001), vasomotor symptom severity (b = -0.324; 95% CI, -0.985 to 0.051; P < .001), and age and (2) SOC (b = 0.150, 95% CI, 0.036-0.331; P = .008), vasomotor symptom severity (b = -0.361; 95% CI, -0.743 to 0.245; P < .001), and age. Both models were adjusted for menopausal age, diabetes mellitus, hypertension, type of menopause, and menopausal hormone therapy intake. SOC was associated with Beck depression scores (β = -0.487, P < .001; Greene Climacteric Scale total scores, β = -0.199, P < .001). FSFI score <26.5 vs >26.5 was associated with SOC (odds ratio, 0.982; 95% CI, 0.563 to 1.947; P = .006) and moderate to severe vasomotor symptom severity (odds ratio, 2.476; 95% CI, 1.478 to 3.120; P = .009) independent of age, diabetes mellitus, hypertension, menopausal hormone therapy intake, type of menopause, or Beck depression classification.

CLINICAL IMPLICATIONS

The results indicate the importance of psychometric assessment of postmenopausal women when presenting with scores of low sexual function. The severity of vasomotor symptoms should also be addressed in any case.

STRENGTHS AND LIMITATIONS

This is the first study investigating the relationship between SOC and sexuality in menopause in a carefully selected homogenous population. Limitations included the cross-sectional design and the fact that sexual distress was not assessed.

CONCLUSIONS

Pathologic FSFI scores were highly prevalent in this sample of postmenopausal women. FSFI is associated positively with age and severity of vasomotor symptoms and negatively with SOC.

The regulatory effect of sex steroids on the RhoA/ROCK pathway in the rat distal vagina

BACKGROUND

Sex steroids have been demonstrated as important modulators of vaginal function. The RhoA/ROCK calcium-sensitizing pathway plays a role in genital smooth muscle contractile mechanism, but its regulation has never been elucidated.

AIM

This study investigated the sex steroid regulation of the vaginal smooth muscle RhoA/ROCK pathway using a validated animal model.

METHODS

Ovariectomized (OVX) Sprague-Dawley rats were treated with 17β-estradiol (E2), testosterone (T), and T with letrozole (T + L) and compared with intact animals. Contractility studies were performed to test the effect of the ROCK inhibitor Y-27632 and the nitric oxide (NO) synthase inhibitor L-NAME. In vaginal tissues, ROCK1 immunolocalization was investigated; mRNA expression was analyzed by semiquantitative reverse transcriptase-polymerase chain reaction; and RhoA membrane translocation was evaluated by Western blot. Finally, rat vaginal smooth muscle cells (rvSMCs) were isolated from the distal vagina of intact and OVX animals, and quantification of the RhoA inhibitory protein RhoGDI was performed after stimulation with NO donor sodium nitroprusside, with or without administration of the soluble guanylate cyclase inhibitor ODQ or PRKG1 inhibitor KT5823.

OUTCOMES

Androgens are critical in inhibiting the RhoA/ROCK pathway of the smooth muscle compartment in the distal vagina.

RESULTS

ROCK1 was immunolocalized in the smooth muscle bundles and blood vessel wall of the vagina, with weak positivity detected in the epithelium. Y-27632 induced a dose-dependent relaxation of noradrenaline precontracted vaginal strips, decreased by OVX and restored by E2, while T and T + L decreased it below the OVX level. In Western blot analysis, when compared with control, OVX significantly induced RhoA activation, as revealed by its membrane translocation, with T reverting it at a level significantly lower than in controls. This effect was not exerted by E2. Abolishing NO formation via L-NAME increased Y-27632 responsiveness in the OVX + T group; L-NAME had partial effects in controls while not modulating Y-27632 responsiveness in the OVX and OVX + E2 groups. Finally, stimulation of rvSMCs from control animals with sodium nitroprusside significantly increased RhoGDI protein expression, counteracted by ODQ and partially by KT5823 incubation; no effect was observed in rvSMCs from OVX rats.

CLINICAL IMPLICATIONS

Androgens, by inhibiting the RhoA/ROCK pathway, could positively contribute to vaginal smooth muscle relaxation, favoring sexual intercourse.

STRENGTHS AND LIMITATIONS

This study describes the role of androgens in maintaining vaginal well-being. The absence of a sham-operated animal group and the use of the only intact animal as control represented a limitation to the study.

Revisiting the physiological role of androgens in women

INTRODUCTION

Extensive research underlines the critical functions of androgens in females. Nevertheless, the precise mechanisms of their action are poorly understood. Here, we review the existing literature regarding the physiological role of androgens in women throughout life.

AREAS COVERED

Several studies show that androgen receptors (ARs) are broadly expressed in numerous female tissues. They are essential for many physiological processes, including reproductive, sexual, cardiovascular, bone, muscle, and brain health. They are also involved in adipose tissue and liver function. Androgen levels change with the menstrual cycle and decrease in the first decades of life, independently of menopause.

EXPERT OPINION

To date, studies are limited by including small numbers of women, the difficulty of dosing androgens, and their cyclical variations. In particular, whether androgens play any significant role in regulating the establishment of pregnancy is poorly understood. The neural functions of ARs have also been investigated less thoroughly, although it is expressed at high levels in brain structures. Moreover, the mechanism underlying the decline of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) with age is unclear. Other factors, including estrogen's effect on adrenal androgen production, reciprocal regulation of ARs, and non-classical effects of androgens, remain to be determined.

Testosterone positively regulates vagina NO-induced relaxation: an experimental study in rats

PURPOSE

Female sexual response involves a complex interplay between neurophysiological mechanisms and the nitric oxide (NO)-mediated relaxation of clitoris and vagina. The aim of this study was to evaluate sex steroids regulation of the relaxant pathway in vagina, using a validated animal model.

METHODS

Subgroups of OVX Sprague-Dawley rats were treated with 17β-estradiol, testosterone, or testosterone and letrozole, and compared with a group of intact animals. Masson's trichrome staining was performed for morphological evaluation of the distal vaginal wall, in vitro contractility studies investigated the effect of OVX and in vivo treatments on vaginal smooth muscle activity. RNA from vaginal tissue was analyzed by semi-quantitative RT-PCR.

RESULTS

Immunohistochemical analysis showed that OVX induced epithelial and smooth muscle structural atrophy, testosterone and testo + letrozole increased the muscle bundles content and organization without affecting the epithelium while 17β-estradiol mediated the opposite effects. In vitro contractility studies were performed on noradrenaline pre-contracted vaginal strips from each experimental group. Acetylcholine (0.001-10 µM) stimulation induced a concentration-dependent relaxation, significantly reduced by NO-synthase inhibitor L-NAME and by guanylate cyclase inhibitor ODQ. OVX resulted in a decreased responsiveness to acetylcholine, restored by testosterone, with or without letrozole, but not by 17β-estradiol. OVX sensitivity to the NO-donor SNP was higher than in the control. Vardenafil, a PDE5 inhibitor, enhanced SNP effect in OVX + testosterone as well as in control, as supported by RNA expression analysis.

CONCLUSIONS

Our study demonstrates that testosterone improves the NO-mediated smooth muscle vaginal cells relaxation confirming its role in maintaining the integrity of muscular relaxant machinery.

Hormonal response after masturbation in young healthy men - a randomized controlled cross-over pilot study

BACKGROUND

Hormones like testosterone play a crucial role in performance enhancement and muscle growth. Therefore, various attempts to increase testosterone release and testosterone concentration have been made, especially in the context of resistance training. Among practitioners, sexual activity (coitus and masturbation) a few hours before training is often discussed to result in increases of testosterone concentration and thus promote muscle growth. However, there is no evidence to support this assumption and the kinetics of the testosterone and cortisol response after sexual activity have not been adequately investigated. Therefore, the aim of this pilot-study was to examine the kinetics of hormone concentrations of total testosterone, free testosterone and cortisol and their ratios after masturbation. In a three-arm single blinded cross-over study, the effects of masturbation with visual stimulus were compared to a visual stimulus without masturbation and the natural kinetics in healthy young men.

RESULTS

The results showed a significant between-condition difference in free testosterone concentrations. Masturbation (p < 0.01) and a visual stimulus (p < 0.05) may seem to counteract the circadian drop of free testosterone concentrations over the day. However, no statistical change was observed in the ratios between total testosterone, free testosterone and cortisol.

CONCLUSIONS

It can be assumed that masturbation may have a potential effect on free testosterone concentrations but not on hormonal ratios. However, additional studies with larger sample sizes are needed to validate these findings.

Effects of testosterone treatment on clitoral haemodynamics in women with sexual dysfunction

PURPOSE

To explore the effects of 6-month systemic testosterone (T) administration on clitoral color Doppler ultrasound (CDU) parameters in women with female sexual dysfunction (FSD).

METHODS

81 women with FSD were retrospectively recruited. Data on CDU parameters at baseline and after 6 months with four different treatments were available and thus further longitudinally analyzed: local non-hormonal moisturizers (NH group), n = 37; transdermal 2% T gel 300 mcg/day (T group), n = 23; local estrogens (E group), n = 12; combined therapy (T + E group), n = 9. Patients underwent physical, laboratory, and genital CDU examinations at both visits and completed different validated questionnaires, including the Female Sexual Function Index (FSFI).

RESULTS

At 6-month visit, T therapy significantly increased clitoral artery peak systolic velocity (PSV) when compared to both NH (p < 0.0001) and E (p < 0.0001) groups. A similar increase was found in the T + E group (p = 0.039 vs. E). In addition, T treatment was associated with significantly higher FSFI desire, pain, arousal, lubrication, orgasm, and total scores at 6-month visit vs. baseline. Similar findings were observed in the T + E group. No significant differences in the variations of total and high-density lipoprotein-cholesterol, triglycerides, fasting glycemia, insulin and glycated hemoglobin levels were found among the four groups. No adverse events were observed.

CONCLUSION

In women complaining for FSD, systemic T administration, either alone or combined with local estrogens, was associated with a positive effect on clitoral blood flow and a clinical improvement in sexual function, showing a good safety profile.

TRIAL REGISTRATION NUMBER

NCT04336891; date of registration: April 7, 2020.

Clitoral Priapism in a Transgender Male

Introduction

Clitoral priapism due to venous outflow obstruction is a rare event and medical emergency. Androgen-induced clitoromegaly in transgender men has not been previously identified as a risk factor.

Aims

Advance current knowledge on identification and treatment of clitoral priapism in the transgender male.

Methods

A 32 year-old presurgical transgender male underwent gender-affirming laparoscopic total hysterectomy and bilateral salpingo-oöphorectomy without incident. Seven days postop, he developed progressive and painful clitoral engorgement that was persistent. Examination and imaging were consistent with clitoral priapism.

Results

Clitoral priapism was treated with adrenergic drugs (imipramine and pseudoephedrine) with rapid resolution of symptoms.

Conclusion

Clitoral priapism is a rare phenomenon usually associated with use of a psychotropic medication. Whether clitoromegaly secondary to androgen administration in transgender men is a risk factor for this rare medical emergency is unknown. Prompt recognition and treatment is paramount.

Kusko RE, Singhal E, Kauffman RP. Clitoral Priapism in a Transgender Male. Sex Med 2021;9:100431.

Effect of Zinc on Testosterone Levels and Sexual Function of Postmenopausal Women: A Randomized Controlled Trial

This study aimed to investigate the effect of zinc supplementation on testosterone levels and sexual function in postmenopausal women. This randomized clinical trial was performed on 116 postmenopausal women with serum zinc levels below 62, and low sexual function who were randomly divided into two groups: intervention and control. Serum zinc levels, testosterone, hemoglobin and hematocrit, as well as their Female Sexual Function Index (FSFI) were evaluated before and after the intervention. Data analysis was performed using paired and independent t-tests, Fisher's exact test, and Chi Square test. The use of zinc supplementation in the intervention group significantly improved sexual desire, arousal, orgasm, satisfaction, vaginal moisture, and pain during intercourse and also the overall score of sexual function compared to the control group (p < 0.001). Zinc supplementation in the intervention group, resulted in a significant increase in testosterone levels compared to the control group, which improved sexual function in postmenopausal women non-significantly. The results of this study showed that zinc supplementation can improve testosterone levels and sexual function in postmenopausal women. Using this supplement in postmenopausal women having zinc insufficiency is recommended. Also, there is need for more studies to prove the effect of zinc on testosterone and sexual function.

Overexpressing miR-122-5p Inhibits the Relaxation of Vaginal Smooth Muscle in Female Sexual Arousal Disorder by Targeting Vasoactive Intestinal Peptide Receptor 1

Introduction

Female sexual arousal disorder (FSAD) is a common issue causing physical and psychological pain, but it has no standard diagnostic criteria or treatment. So its pathogenesis desiderates to be explored.

Aim

To investigate the specific function of miR-122-5p in FSAD.

Methods

18 subjects were grouped into FSAD and normal control groups according to the Chinese version of the Female Sexual Function Index, and the expression levels of miR-122-5p and vasoactive intestinal peptide receptor 1 (VIPR1) protein in their tissue were verified through real-time quantitative polymerase chain reaction (qRT-PCR) and western blot (WB) analysis. Then in vitro experiment, miR-122-5p was overexpressed or inhibited in rat vaginal smooth muscle cells (SMCs). The relaxation of rat vaginal SMCs was reflected by the cell morphology, intracellular free cytosolic calcium ion (Ca²⁺) levels, cell proliferation and apoptosis, together with the cyclic adenosine monophosphate (cAMP) concentration and protein kinase A (PKA) activities. Additionally, the expression levels of relaxation-related proteins, including VIPR1, stimulatory G protein (Gs), adenylate cyclase (AC), and PKA, were detected based on WB analysis. Furthermore, a rescue experiment that simultaneously overexpressed or silenced miR-122-5p and VIPR1 was conducted, and all the indicators were evaluated.

Main Outcomes Measure

The expression level of VIPR1 and downstream proteins, cell morphology, cell proliferation and apoptosis, and intracellular free Ca²⁺ levels were examined.

Results

We verified that women with FSAD had higher miR-122-5p and lower VIPR1 protein. Then overexpressing miR-122-5p decreased relaxation of rat vaginal SMCs, which was manifested as a contractile morphology of cells, an increased intracellular free Ca²⁺ concentration, and lower cAMP concentration and PKA activity. Moreover, by rescue experiments, we inferred that VIPR1 was the target of miR-122-5p and affected the relaxation function of vaginal SMCs.

Conclusion

miR-122-5p regulates the relaxation of vaginal SMCs in FSAD by targeting VIPR1, ulteriorly providing an underlying diagnostic and therapeutic target for FSAD.

Cong S, Gui T, Shi Q, et al. Overexpressing miR-122-5p Inhibits the Relaxation of Vaginal Smooth Muscle in Female Sexual Arousal Disorder by Targeting Vasoactive Intestinal Peptide Receptor 1. Sex Med 2021;9:100390.

International Society for the Study of Women's Sexual Health Clinical Practice Guideline for the Use of Systemic Testosterone for Hypoactive Sexual Desire Disorder in Women

AIM

To provide a clinical practice guideline for the use of testosterone including identification of patients, laboratory testing, dosing, post-treatment monitoring, and follow-up care in women with hypoactive sexual desire disorder (HSDD).

METHODS

The International Society for the Study of Women's Sexual Health appointed a multidisciplinary panel of experts who performed a literature review of original research, meta-analyses, review papers, and consensus guidelines regarding testosterone use in women. Consensus was reached using a modified Delphi method.

OUTCOMES

A clinically useful guideline following a biopsychosocial assessment and treatment approach for the safe and efficacious use of testosterone in women with HSDD was developed including measurement, indications, formulations, prescribing, dosing, monitoring, and follow-up.

RESULTS

Although the Global Position Statement endorses testosterone therapy for only postmenopausal women, limited data also support the use in late reproductive age premenopausal women, consistent with the International Society for the Study of Women's Sexual Health Process of Care for the Management of HSDD. Systemic transdermal testosterone is recommended for women with HSDD not primarily related to modifiable factors or comorbidities such as relationship or mental health problems. Current available research supports a moderate therapeutic benefit. Safety data show no serious adverse events with physiologic testosterone use, but long-term safety has not been established. Before initiation of therapy, clinicians should provide an informed consent. Shared decision-making involves a comprehensive discussion of off-label use, as well as benefits and risks. A total testosterone level should not be used to diagnose HSDD, but as a baseline for monitoring. Government-approved transdermal male formulations can be used cautiously with dosing appropriate for women. Patients should be assessed for signs of androgen excess and total testosterone levels monitored to maintain concentrations in the physiologic premenopausal range. Compounded products cannot be recommended because of the lack of efficacy and safety data.

CLINICAL IMPLICATIONS

This clinical practice guideline provides standards for safely prescribing testosterone to women with HSDD, including identification of appropriate patients, dosing, and monitoring.

STRENGTHS AND LIMITATIONS

This evidence-based guideline builds on a recently published comprehensive meta-analysis and the Global Position Statement endorsed by numerous societies. The limitation is that testosterone therapy is not approved for women by most regulatory agencies, thereby making prescribing and proper dosing challenging.

CONCLUSION

Despite substantial evidence regarding safety, efficacy, and clinical use, access to testosterone therapy for the treatment of HSDD in women remains a significant unmet need.

International Society for the Study of Women's Sexual Health Clinical Practice Guideline for the Use of Systemic Testosterone for Hypoactive Sexual Desire Disorder in Women

Background: The Global Consensus Position Statement on the Use of Testosterone Therapy for Women (Global Position Statement) recommended testosterone therapy for postmenopausal women with hypoactive sexual desire disorder (HSDD).

Aim: To provide a clinical practice guideline for the use of testosterone including identification of patients, laboratory testing, dosing, post-treatment monitoring, and follow-up care in women with HSDD.

Methods: The International Society for the Study of Women's Sexual Health appointed a multidisciplinary panel of experts who performed a literature review of original research, meta-analyses, review papers, and consensus guidelines regarding testosterone use in women. Consensus was reached using a modified Delphi method.

Outcomes: A clinically useful guideline following a biopsychosocial assessment and treatment approach for the safe and efficacious use of testosterone in women with HSDD was developed including measurement, indications, formulations, prescribing, dosing, monitoring, and follow-up.

Results: Although the Global Position Statement endorses testosterone therapy for only postmenopausal women, limited data also support the use in late reproductive age premenopausal women, consistent with the International Society for the Study of Women's Sexual Health Process of Care for the Management of HSDD. Systemic transdermal testosterone is recommended for women with HSDD not primarily related to modifiable factors or comorbidities such as relationship or mental health problems. Current available research supports a moderate therapeutic benefit. Safety data show no serious adverse events with physiologic testosterone use, but long-term safety has not been established. Before initiation of therapy, clinicians should provide an informed consent. Shared decision-making involves a comprehensive discussion of off-label use, as well as benefits and risks. A total testosterone level should not be used to diagnose HSDD, but as a baseline for monitoring. Government-approved transdermal male formulations can be used cautiously with dosing appropriate for women. Patients should be assessed for signs of androgen excess and total testosterone levels monitored to maintain concentrations in the physiologic premenopausal range. Compounded products cannot be recommended because of the lack of efficacy and safety data.

Clinical Implications: This clinical practice guideline provides standards for safely prescribing testosterone to women with HSDD, including identification of appropriate patients, dosing, and monitoring.

Strengths & Limitations: This evidence-based guideline builds on a recently published comprehensive meta-analysis and the Global Position Statement endorsed by numerous societies. The limitation is that testosterone therapy is not approved for women by most regulatory agencies, thereby making prescribing and proper dosing challenging.

Conclusion: Despite substantial evidence regarding safety, efficacy, and clinical use, access to testosterone therapy for the treatment of HSDD in women remains a significant unmet need.

Construction of circRNA-miRNA-mRNA Network for Exploring Underlying Mechanisms of Lubrication Disorder

Lubrication disorder is a common health issue that manifests as insufficient sexual arousal at the beginning of sex. It often causes physical and psychological distress. However, there are few studies on lubrication disorder, and the complexity of circular RNA (circRNA) and the related competing endogenous RNA (ceRNA) network in lubrication disorder is still poorly known. Therefore, this study aims to build a regulatory circRNA-micro (mi)RNA-mRNA network and explore potential molecular markers of lubrication disorder. In the study, 12 subjects were recruited, including 6 in the lubrication disorder group and 6 in the normal control group. RNA sequencing was exploited to identify the expression profiles of circRNA, miRNA and mRNA between two groups, and then to construct the circRNA-miRNA-mRNA networks. The enrichment analyses of the differentially expressed (DE)-mRNAs were examined via Gene Set Enrichment Analysis (GSEA). Furthermore, the expression level and interactions among circRNA, miRNA, and mRNA were validated using real-time quantitative polymerase chain reaction (RT-qPCR) and dual-luciferase reporter assays. In the results, 73 circRNAs, 287 miRNAs, and 354 target mRNAs were differentially expressed between two groups when taking | Log2 (fold change)| > 1 and P-value < 0.05 as criteria, and then the results of GSEA revealed that DE-mRNAs were linked with "vascular smooth muscle contraction," "aldosterone regulated sodium reabsorption," "calcium signaling pathway," etc. 19 target relationships among 5 circRNAs, 4 miRNAs, and 7 mRNAs were found and constructed the ceRNA network. Among them, hsa-miR-212-5p and hsa-miR-874-3p were demonstrated to be related to the occurrence of lubrication disorder. Eventually, consistent with sequencing, RT-qPCR showed that hsa_circ_0026782 and ASB2 were upregulated while hsa-miR-874-3p was downregulated, and dual-luciferase reporter assays confirmed the interactions among them. In summary, the findings indicate that the circRNA-miRNA-mRNA regulatory network is presented in lubrication disorder, and ulteriorly provide a deeper understanding of the specific regulatory mechanism of lubrication disorder from the perspective of the circRNA-miRNA-mRNA network.

Insight on the Intracrinology of Menopause: Androgen Production within the Human Vagina

In this study, we investigated steroidogenic gene mRNA expression in human vaginas and verified the ability of human vagina smooth muscle cells (hvSMCs) to synthesize androgens from upstream precursor dehydroepiandrosterone (DHEA). As a readout for androgen receptor (AR) activation, we evaluated the mRNA expression of various androgen-dependent markers. hvSMCs were isolated from vagina tissues of women undergoing surgery for benign gynecological diseases. In these cells, we evaluated mRNA expression of several steroidogenic enzymes and sex steroid receptors using real time reverse transcription-polymerase chain reaction. Androgen production was quantified with liquid chromatography tandem-mass spectrometry (LC-MS/MS). In vaginal tissues, AR mRNA was significantly less expressed than estrogen receptor α, whereas in hvSMCs, its mRNA expression was higher than progestin and both estrogen receptors. In hvSMCs and in vaginal tissue, when compared to ovaries, the mRNA expression of proandrogenic steroidogenic enzymes (HSD3β1/β2, HSD17β3/β5), along with 5α-reductase isoforms and sulfotransferase, resulted as being more abundant. In addition, enzymes involved in androgen inactivation were less expressed than in the ovaries. The LC-MS/MS analysis revealed that, in hvSMCs, short-term DHEA supplementation increased Δ4-androstenedione levels in spent medium, while increasing testosterone and DHT secretion after longer incubation. Finally, androgenic signaling activation was evaluated through AR-dependent marker mRNA expression, after DHEA and T stimulation. This study confirmed that the human vagina is an androgen-target organ with the ability to synthesize androgens, thus providing support for the use of androgens for local symptoms of genitourinary syndrome in menopause.

Testosterone, cardiomyopathies, and heart failure: a narrative review

Testosterone exerts an important regulation of cardiovascular function through genomic and nongenomic pathways. It produces several changes in cardiomyocytes, the main actor of cardiomyopathies, which are characterized by pathological remodeling, eventually leading to heart failure. Testosterone is involved in contractility, in the energy metabolism of myocardial cells, apoptosis, and the remodeling process. In myocarditis, testosterone directly promotes the type of inflammation that leads to fibrosis, and influences viremia with virus localization. At the same time, testosterone exerts cardioprotective effects that have been observed in different studies. There is increasing evidence that low endogenous levels of testosterone have a negative impact in some cardiomyopathies and a protective impact in others. This review focuses on the interrelationships between testosterone and cardiomyopathies and heart failure.

Olfactory Exposure to β-Caryophyllene Increases Testosterone Levels in Women's Saliva

INTRODUCTION

From previous studies, we hypothesized that olfactory exposure to β-caryophyllene stimulates women's libido. However, Japan's sex culture is so closed that it is difficult to test this possibility without accumulating scientific evidence. Therefore, it is necessary to measure the concentration of sex-related hormones in saliva, an experimental technique that is relatively easy to obtain research permission, and to obtain a scientific basis to convince ethics committee reviewers.

AIM

The aim of this study is to investigate whether β-caryophyllene increases salivary testosterone concentrations associated with libido and vaginal sensation during intercourse in women.

METHODS

19 women in the follicular phase of the menstrual cycle participated in the study. The subjects then sat in front of the odor exposure device we had created. Each subject was exposed to dipropylene glycol for 20 minutes, followed by 3% β-caryophyllene for 20 minutes. Saliva was collected 4 times: before and after control exposure, and before and after β-caryophyllene exposure.

MAIN OUTCOME MEASURE

Salivary testosterone and estrogen concentrations were measured with a competition ELISA.

RESULTS

β-caryophyllene significantly increased the salivary concentration of testosterone (control vs β-caryophyllene; 0.97 ± 0.05 vs 1.13 ± 0.03, P = .00, 95% confidence interval of control: 0.84-1.09, 95% confidence interval of β-caryophyllene: 1.04-1.20) but not estrogen (control vs β-caryophyllene; 1.05 ± 0.03 vs 1.07 ± 0.04, P = .69, 95% confidence interval of control: 0.96-1.12, 95% confidence interval of β-caryophyllene: 0.98-1.15).

STRENGTHS & LIMITATIONS

The personal preferences of the subjects and the order of exposure may have affected the results.

CONCLUSION

β-caryophyllene may be a remedy with fewer side effects for women with decreased libido. We believe that β-caryophyllene may be a remedy for women with decreased libido. However, this hypothesis must be tested by further clinical studies. Wataru Tarumi, Kazuyuki Shinohara. Olfactory Exposure to β-Caryophyllene Increases Testosterone Levels in Women's Saliva. J Sex Med 2020;8:525-531.

The non-aromatizable androgen dihydrotestosterone (DHT) facilitates sexual behavior in ovariectomized female rats primed with estradiol

It is still unclear whether Testosterone (T) increases sexual desire through a stimulation of the androgen receptor in relevant brain regions or through its conversion to estrogens. The aim of this study was to clarify the mechanisms of T facilitation of female sexual desire by assessing the effect of a non-aromatizable androgen (Dihydrotestosterone, DHT) in a validated animal model. Ovariectomized (OVX) Long-Evans rats were treated with oil (O) + O, 10 mcg Estradiol Benzoate (EB) + O, 10 mcg EB + 500 mcg Progesterone (P), O + 500 mcg DHT or 10 mcg EB + 500 mcg DHT (n = 12 per group). EB was administered 48 h, while P and DHT 4 h, prior to 4 sexual behavioral testing sessions in bisected unilevel pacing chambers. Appetitive behaviors (the frequencies of hops/darts and solicitations) were considered as the main outcome measure. Sexual receptivity indexes [lordosis magnitude, expressed as lordosis rating (LR), and lordosis quotient (LQ)], rejection responses, as well as mounts, intromissions and ejaculations received from the male were also coded. The probability of transition among sexual behaviors was evaluated by Transition Matrices; T-Pattern analysis was performed to detect hidden repeated temporal behavioral sequences. Preliminary analyses found no statistically significant differences between the O + O and EB + O groups, therefore we excluded the EB + O group from further analyses. Rats treated with EB + DHT displayed significantly more appetitive behaviors compared to negative controls (O + O and O + DHT), whereas no difference was observed between EB + DHT rats and positive controls (EB + P); noteworthy, a higher number of appetitive behaviors was observed in the O + DHT group compared to the O + O group. Furthermore, rats treated with EB + DHT showed significantly higher receptivity measures (LR and LQ) and received more mounts, intromissions and ejaculations compared to negative controls (O + O and O + DHT), to levels equivalent to EB + P. No differences were detected in female-male mounts or rejection responses among the 4 groups. Under a qualitative perspective, full solicitation was found exclusively in T-patterns of the EB + DHT group, which was also the only one to display T-patterns of higher order encompassing appetitive behaviors-only events. In conclusion, the administration of DHT in EB-primed OVX Long-Evans rats enhances sexual behavior measures. Specifically, DHT seems to stimulate sequences of appetitive behaviors separated from copulative/reproductive measures. Our data support an independent role of androgens in the facilitation of female sexual desire.

The role of androgens in the treatment of genitourinary syndrome of menopause (GSM): International Society for the Study of Women's Sexual Health (ISSWSH) expert consensus panel review

OBJECTIVE

The objective of this consensus document is to broaden the perspective on clinical management of genitourinary syndrome of menopause to include androgens.

METHODS

A modified Delphi method was used to reach consensus among the 14 international panelists representing multiple disciplines and societies.

RESULTS

Menopause-related genitourinary symptoms affect over 50% of midlife and older women. These symptoms have a marked impact on sexual functioning, daily activities, emotional well-being, body image, and interpersonal relations. Tissues in the genitourinary system are both androgen and estrogen-dependent. The clitoris, vestibule, including minor and major vestibular glands, urethra, anterior vaginal wall, periurethral tissue, and pelvic floor are androgen-responsive. Historically, treatment of postmenopausal genitourinary symptoms involved both androgens and estrogens. This subsequently gave rise to predominantly estrogen-based therapies. More recently, double-blind, placebo-controlled clinical trials have demonstrated that local vaginal dehydroepiandrosterone improves symptoms in postmenopausal women, including moderate to severe dyspareunia. Limited data suggest that systemic testosterone treatment may improve vaginal epithelial health and blood flow. Open-label studies that have used high doses of intravaginal testosterone in the presence of aromatase inhibitor therapy for breast cancer have resulted in supraphysiological serum testosterone levels, and have been reported to lower vaginal pH, improve the vaginal maturation index, and reduce dyspareunia.

CONCLUSIONS

Vaginal dehydroepiandrosterone, hypothesized to enhance local production of both androgen and estrogen, is effective for the management of dyspareunia in menopause. Vaginal testosterone offers potential as a treatment for genitourinary syndrome of menopause, but more studies are needed.

Maternal exposure to bisphenol A during pregnancy interferes testis development of F1 male mice

This study was conducted to investigate the effects of maternal exposure to bisphenol A (BPA) on testis development of F1 male mice. The BPA exposure model of pregnant mice was prepared by intragastric administration of BPA at the doses of 0, 2.5, 5, 10, 20, and 40 mg/kg/day at gestation day (GD) 0.5-17.5. The testis index of the offspring mice was calculated at postnatal day (PND) 21 and PND 56. The results showed that maternal exposure to 20 mg/kg BPA during pregnancy significantly increased the testicular index of F1 males at PND 21, and 40 mg/kg BPA significantly decreased the testicular index of F1 males at PND 56 (P < 0.01). BPA significantly reduced serum testosterone (T) and estradiol (E2) levels, and improved testicular ERα and ERβ levels in F1 males at both PND 21 and PND 56. BPA exposure also upregulated transcription of testicular Dnmt1 and inhibited the transcription of testicular Dnmt3A and Dnmt3B in F1 mice at PND 21. BPA reduced the transcriptional level of testicular DNA methyltransferase (Dnmt), increased the expression of testicular caspase-7, caspase-9, and bax, and decreased the expression of bcl-2 in F1 mice at PND 56. Consistent with that, BPA improved the apoptosis rate in the testis at PND 56 (P < 0.01 or P < 0.05). Our study indicates that BPA disrupts the secretion of testosterone, estradiol, and estrogen receptors by interfering with the transcription of testicular DNA methyltransferase (Dnmt) in offspring males, which damages testicular tissues and affects the potential reproductive function.

Effects of ovarian hormones on the emission of 50-kHz ultrasonic vocalizations during distributed clitoral stimulation in the rat

Fifty-kHz ultrasonic vocalizations (USVs) are emitted by adult rats during appetitive phases of behavior in response to stimuli thought to be associated with a positive affective state. In particular, 50-kHz USVs with rapid frequency oscillations, known as trills and flat-trills, in which these oscillations are flanked by a monotonic portion, are together positively correlated with appetitive behaviors such as rough and tumble play, drug and natural reward, and mating. Female rats produce 50-kHz USVs during a variety of sexual contexts, yet data are still vague as female sexual behavior is seldom studied on its own. Distributed clitoral stimulation (CLS) offers a unique approach to investigating female 50-kHz USVs as it mimics stimulation received during mating. Although CLS induces a sexual reward state, it is unknown whether CLS elicits trills and flat-trills. We addressed this question using eight ovariectomized rats, we investigated whether ovarian hormones augmented these call subtypes in response to CLS. The combined and separate effects of estradiol benzoate (EB) and progesterone (P), and oil vehicle were assessed through comparison of these call subtypes between CLS and inter-CLS interval. We found that CLS with EB + P significantly increased call duration and rate, lowered peak frequency, and widened the bandwidth of trills. Flat-trills showed a similar pattern except for call duration. Call distribution during the CLS and inter-CLS interval suggest that trill and flat-trills may be indicative of both anticipatory and sexual reward.

From inflammation to sexual dysfunctions: a journey through diabetes, obesity, and metabolic syndrome

Metabolic diseases are associated with chronic low-grade inflammation, which has been indicated as a potential mediator of endothelial dysfunction and cardiovascular disease. Visceral adiposity is thought to be the starting condition of the inflammatory state through the release of inflammatory cytokines, including TNF-alpha, CRP, and IL-6, which in turn promote endothelial dysfunction, endothelial expression of chemokines (IL-1) and adhesion molecules (ICAM-1, VCAM-1, and P-selectin), and the inhibition of anti-atherogenic factors (adiponectin). Obesity, metabolic diseases, and diabetes, all conditions characterized by abdominal fat, are well-recognized risk factors for sexual dysfunction in both sexes. Evidence from randomized-controlled trials supports the association between inflammatory milieau and erectile dysfunction in men suffering from metabolic diseases, whereas, in women, this has to be confirmed in further studies. A healthy lifestyle based on dietary pattern with high content of whole grain, fruit, nuts and seeds, and vegetables and low in sodium and saturated fatty acids plus regular physical activity may help to modulate the pro-inflammatory state associated with metabolic diseases and the related burden of sexual dysfunctions.

Molecular basis of androgen action on human sexual desire

Reproduction is a fundamental process for the species maintenance and the propagation of genetic information. The energy expenditure for mating is overtaken by motivational stimuli, such as orgasm, finely regulated by steroid hormones, gonadotropins, neurotransmitters and molecules acting in the brain and peripheral organs. These functions are often investigated using animal models and translated to humans, where the androgens action is mediated by nuclear and membrane receptors converging in the regulation of both long-term genomic and rapid non-genomic signals. In both sexes, testosterone is a central player of this game and is involved in the regulation of sexual desire and arousal, and, finally, in reproduction through cognitive and peripheral physiological mechanisms which may decline with aging and circadian disruption. Finally, genetic variations impact on reproductive behaviours, resulting in sex-specific effect and different reproductive strategies. In this review, androgen actions on sexual desire are evaluated, focusing on the molecular levels of interaction.

Genomic and non-genomic effects of androgens in the cardiovascular system: clinical implications

The principle steroidal androgens are testosterone and its metabolite 5α-dihydrotestosterone (DHT), which is converted from testosterone by the enzyme 5α-reductase. Through the classic pathway with androgens crossing the plasma membrane and binding to the androgen receptor (AR) or via mechanisms independent of the ligand-dependent transactivation function of nuclear receptors, testosterone induces genomic and non-genomic effects respectively. AR is widely distributed in several tissues, including vascular endothelial and smooth muscle cells. Androgens are essential for many developmental and physiological processes, especially in male reproductive tissues. It is now clear that androgens have multiple actions besides sex differentiation and sexual maturation and that many physiological systems are influenced by androgens, including regulation of cardiovascular function [nitric oxide (NO) release, Ca²⁺ mobilization, vascular apoptosis, hypertrophy, calcification, senescence and reactive oxygen species (ROS) generation]. This review focuses on evidence indicating that interplay between genomic and non-genomic actions of testosterone may influence cardiovascular function.

Micturition dysfunction in four-month old ovariectomized rats: Effects of testosterone replacement

AIMS

Androgen deficiency has been implicated in urological complications of postmenopausal women. This study examined the effects of testosterone replacements on the lower urinary tract dysfunction in 4-month old ovariectomized (OVX) rats.

MAIN METHODS

Sprague-Dawley female rats were OVX bilaterally. Three months later, rats received single intramuscular injections of testosterone undecanoate. Cystometric study, and bladder and urethra smooth muscle reactivities were evaluated.

KEY FINDINGS

Ovariectomy reduced by 65% (p<0.05) the serum testosterone levels. Testosterone replacement at 5mg/kg restored serum hormone levels to baseline, whereas 10mg/kg produced 14-fold higher testosterone levels. OVX rats exhibited significant increases of body weight, perigonadal fat and blood pressure, and reduced uterus weight, but none of these parameters were changed by testosterone replacements. OVX rats exhibited micturition dysfunction characterized by increases of basal pressure, threshold pressure, voiding frequency and post-voiding pressure. In addition, the bladder contractions induced by electrical-field stimulation (EFS) and carbachol were significantly reduced, whereas angiotensin II-induced urethral contractions were significantly increased in OVX rats. Testosterone replacement at 10mg/kg (but not at 5mg/kg) dose fully normalized the in vivo micturition dysfunction, as well as the in vitro bladder and urethral alterations. Testosterone (10mg/kg) also significantly potentiated the bladder relaxations induced by the β₃-adrenoceptor agonist mirabegron. The protective effects of testosterone were not modified by concomitant treatment with the aromatase inhibitor letrozole (2.5mg/kg, 4weeks).

SIGNIFICANCE

The improvement of micturition dysfunction by testosterone replacement suggests that androgen therapy might be of therapeutic benefit for urological complications associated with post-menopause.