Mechanistic analysis of erectile dysfunction in a depression rat model

Associations between organic erectile dysfunction and the risk of herpes zoster and postherpetic neuralgia in men

BACKGROUND

Whether erectile dysfunction (ED) leads to considerable stress for affected men remains unclear? In this study, we investigated whether organic ED (OED) is associated with increased risks of herpes zoster (HZ) and postherpetic neuralgia (PHN).

METHODS

A representative subset of Taiwan's National Health Insurance Research Database was employed for this study. Enrollees with OED from the years 2000 to 2018 were selected. To ensure comparability between the case and control groups, we implemented 1:1 propensity score matching based on age, index year, comorbidities, and medications.

RESULTS

The case group included 20,808 patients with OED, while the control group consisted of 20,808 individuals without OED. The OED group exhibited a significantly elevated risk of HZ (adjusted hazard ratio [aHR] = 1.74) and PHN (aHR = 1.56) compared to the non-OED group.

CONCLUSIONS

Men experiencing OED seem to face elevated risks of HZ and PHN compared to those without OED. ED may serve as a warning sign for individuals at HZ risk.

Withania somnifera ameliorates sexual arousal and impotence in stressed sexually sluggish male rats by modulating neurotransmitters and NO/cGMP/PDE5α pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Psychological stress is a growing global threat to male sexual potency and erection efficiency. Withania somnifera (L.) Dunal (WS), also known as Ashwagandha, is a well-known Ayurvedic herb. The roots of Withania somnifera improve the body's ability to handle stress, strengthen the immune system, promote healthy ageing, and have aphrodisiac properties with male sexual stimulation effects. Despite its widespread acceptance as an Ayurvedic stress-relieving drug with beneficial effects on male reproductive health, Withania somnifera has yet to be studied for its potential role in improving the sexual arousal and erectile dysfunction of psychologically stressed sexually sluggish males.

AIM OF THE STUDY

To investigate the therapeutic effects of purified root powder of Withania somnifera on sexual behaviour and erectile efficiency in stressed sexually sluggish male rats.

MATERIALS AND METHODS

Sexually sluggish male rats were screened by premating tests after being exposed to a psychological stressor, restraint stress, 3 h/day for 30 days. Subsequently, these rats were treated with purified root powder of WS (150 or 300 mg/kg/day-PO) or sildenafil (5 mg/kg/day-PO) for 30 days. The rats were sacrificed after 24 h of the last treatment, and the effects on various factors related to sexual behaviour, penile histomorphology, serum hormones, and neurotransmitters associated with sexual arousal and penile erection were examined.

RESULTS

WS treatment improves prosexual and sexual behaviour in psychologically stressed sexually sluggish male rats by increasing non-contact erections and mounts, intromission, and ejaculation frequencies, while decreasing sexual exhaustion by decreasing post-ejaculation intervals and latencies. WS also modulates neurotransmitters and hormones associated with sexual desire and stress, including dopamine, serotonin, corticosterone, and prolactin. Additionally, there was also a dose-dependent increase in serum LH, FSH, and testosterone levels. The administration of WS to sexually sluggish rats resulted in significant improvements in penile histomorphology, specifically by increasing the ratio of smooth muscle (SM) to collagen. Furthermore, in sexually sluggish rats, WS treatment increased the expression of markers associated with penile erection facilitation, such as nNOS, eNOS, p-Akt, nitric oxide, acetylcholine, and cGMP. Notably, WS treatment decreased the expression of penile PDE5α in these rats in a dose-dependent manner. Remarkably, the therapeutic effects of WS are comparable to those of sildenafil.

CONCLUSIONS

Purified root powder of Withania somnifera was found to improve sexual arousal and erection efficiency in stressed, sexually sluggish male rats. This improvement was achieved by modulating the HPG and HPA axes as well as the NO/cGMP/PDE5α pathway involved in penile erection. Thus, our findings strongly support the potent therapeutic potential of purified root powder of WS in improving the sexual health of stressed sexually sluggish rats.

Low Exercise Tolerance as a Marker of Erectile Dysfunction and Depression among Post-Myocardial Infarction Men

Evidence has grown recently on the correlation between lifestyle and physical activity, and their impact on the functioning of the entire organism. In addition, a decrease in physical efficiency may be an indicator of the early diagnosis of systemic diseases. The aim of this study was to determine whether there is a relationship between exercise tolerance and possible erectile dysfunction or mental disorders. A cross-sectional study was conducted among 254 men in 4 cardiac rehabilitation centers in Poland using the standardized International Index of Erectile Function 5 (IIEF-5) and Beck Depression Inventory (BDI) questionnaires. Erectile dysfunction was directly proportional to the metabolic equivalent of the task (MET) variable. An increase in exercise tolerance by 1 point was associated with an increase in the IIEF-5 score by 1.62 points, indicating a reduction in the severity of erectile dysfunction. The 1-point increase in MET was associated with a 1.8-point decrease in BDI, indicating that an increase in exercise tolerance is associated with a decrease in the severity of depressive disorders. Increasing the tolerance of physical effort has a beneficial effect not only on the general well-being, but also on the sexual and mental health of men. An increase in exercise tolerance is associated with a reduction in the incidence of erectile dysfunction. On the other hand, in patients with depressive disorders, the improvement of exercise tolerance reduces the intensity of depression symptoms. Exercise tolerance can be an early and simple marker at the onset of erectile dysfunction or mood disorders.

The role of microRNAs in erectile dysfunction: From pathogenesis to therapeutic potential

Erectile dysfunction (ED) is a common male sexual dysfunction disease, and it was predicted that the number of ED patients worldwide will reach 322 million by 2025. However, the pathogenesis of ED is complex and the current treatment options are still limited, so it is urgent to explore new treatment strategies. Recent studies have shown that microRNAs (miRNAs) play an important role in ED, and these single-stranded non-coding small RNA molecules are involved in key pathophysiological processes in the occurrence and development of ED. Therefore, miRNAs have remarkable potential as therapeutic targets in ED. Here, this review introduces the physiological basis of erectile function and the pathophysiological changes in ED and summarizes the current knowledge on the expression, biological functions, and molecular mechanisms of miRNAs in ED, especially the potential of miRNA-targeted therapies to improve ED. This review will provide a comprehensive view of the role of miRNAs in the pathogenesis of ED and the potential value of miRNAs in the treatment of ED.

Genetic evidence suggests that depression increases the risk of erectile dysfunction: A Mendelian randomization study

Background: The causal relationship between depression and erectile dysfunction (ED) is still uncertain.

Objectives: To identify the genetically predicted causality of depression on ED through Mendelian randomization (MR).

Materials and methods: A comprehensive GWAS meta-analysis comprising 807,553 Europeans provided single-nucleotide polymorphism (SNP) information for depression, and another genome-wide association analysis involving 223,805 European ancestries measured SNPs for ED. The inverse variance weighted (IVW) method was used as the primary MR analysis method to evaluate causal effects. In addition, the maximum likelihood method, MR-Egger, weighted median, robust adjusted contour score (MR.RAPS), and MR pleiotropic residual and outlier (MR-PRESSO) methods were used as supplements for sensitivity analysis.

Results: According to the IVW analysis, depression significantly increases the incidence of ED (odds ratio [OR] = 1.68, 95% confidence interval [CI] = 1.38–2.05, p < 0.001). In sensitivity analyses, the ORs for the maximum likelihood method, MR-Egger, weighted median, MR.RAPS, and MR-PRESSO are 1.70 (95% CI = 1.39–2.08, p < 0 .001), 1.94 (95% CI = 0.63–6.01, p > 0 .05), 1.59 (95% CI = 1.21–2.10, p < 0 .001), 1 .70 (95% CI = 1.39–2.08, p < 0 .001), and 1.68 (95% CI = 1.40–2.04, p < 0 .001). There is no clear indication of potential heterogeneity or pleiotropy (p for the MR-Egger intercept = 0.804; p for the global test = 0.594; and p for Cochran’s Q statistics >0.05).

Conclusion: Genetically predicted depression plays a potentially causal role in the occurrence of ED.