The effects of combined free radical scavenger and sildenafil therapy on age-associated erectile dysfunction: An animal model

The protective effect of Ferula elaeochytris on age-related erectile dysfunction

ETHNOPHARMACOLOGICAL RELEVANCE

Ferula elaeochytris Korovin (FE) is a perennial medicinal plant of Apiaceae family. Ferula elaeochytris Korovin, known as 'Çakşır' in Anatolia, is widely used as an aphrodisiac as well as antioxidant, anti-inflammatory, and anti-diabetic.

AIM OF THE STUDY

Erectile dysfunction (ED) is a serious public health problem that has a high prevalence and negatively affects the quality of life in elderly men. In the treatment and prophylaxis of many diseases, because of widely increasing use of plant extracts as therapeutic agents, preclinical studies related to plant extracts are becoming more important by the day. In this study, we aimed to investigate the protective effect of Ferula elaeochytris Korovin (FE) root extract on age-related ED.

MATERIALS AND METHODS

Seventy-two male Wistar albino rats were equally divided into four groups: 4-month aged rats (Y), 24-month aged rats (AG), and FE-administered (20 and 40 mg/kg/day; oral gavage; over 8 weeks) 24-month aged rats (AG + FE). The measurements included: changes in smooth muscle cells and collagen fibrils, tumor necrosis factor alpha (TNF-α), penile neuronal nitric oxide synthase (nNOS) and endothelial nitric oxide synthase (eNOS) expression, serum testosterone concentrations (ST), neurogenic- and endothelial-dependent relaxations of the corpus cavernosum (CC), intracavernosal pressure/mean arterial pressure (ICP/MAP), area under the curve (total ICP), total antioxidant status (TAS), and total oxidant status (TOS) on corpus cavernosal tissue.

RESULTS

These results have an important role in the development of ED. ICP/MAP, total ICP, eNOS/nNOS expressions and ST levels increased in AG+40 mg FE group compared to the AG group, whereas TNF-α levels decreased and oxidative and antioxidant parameters balanced.

CONCLUSIONS

Our findings show that FE may have a useful effect on decelerating the development of age-related ED.

Intranasal Tadalafil nanoemulsions: formulation, characterization and pharmacodynamic evaluation

This study aims at improving the bioavailability of a poorly soluble phosphodiesterase-5 inhibitor; tadalafil (TD) via developing intranasal (IN) nanoemulsions (NEs). Optimum NE ingredients were selected based on solubility studies, emulsification tests, and phase diagram construction. Both o/w and w/o NEs were selected based on their drug loading capacity. Optimum formulations were subjected to physicochemical characterization and were assessed for nasal toxicity through biochemical analysis of tumor necrosis factor-α (TNF-α) and caspase-3 in rat nasal tissues. Pharmacodynamic study was performed via biochemical analysis of cyclic guanosine monophosphate (cGMP) in rat penis 2-h post-treatment and compared with oral suspension of Cialis® tablets. Optimum o/w and w/o NEs were successfully prepared using different ratios of Capmul-MCM-EP, Labrasol:Transcutol-HP (1:1) and water. Optimized formulations exhibited more than 4000-fold increase in TD solubility compared with its aqueous solubility. Both formulations were optically isotropic with the majority of globules in the nanometric-size range. Nasal toxicity study revealed no significant difference in values of TNF-α and caspase-3 between the NE-treated groups and the control group. Both TD-NEs succeeded to achieve a significant enhancement in cGMP levels. Our findings suggested that IN administration of the developed TD-NEs could provide a safe and effective alternative to TD oral delivery.

Hydro-Jet Dissection of the Cavernous Nerves Preserves Erection Function in a Radical Prostatectomy Animal Model

Background

Postoperative erectile dysfunction (ED) remains a prevalent consequence of radical prostatectomy (RP) that significantly impacts patient quality of life. Water-jet technology is widely used for dissection in neurosurgical procedures but novel to urologic surgery.

Aim

To establish the impact of hydro-jet dissection (HJD) of the cavernous nerves (CN) on postoperative erectile function in an animal model of RP-induced ED.

Methods

32 male Sprague-Dawley rats were randomized to 4 groups: Sham surgery (n = 8), bilateral HJD of CN (n = 8), blunt CN injury (n = 8), or stretch CN injury (n = 8). After 4 weeks, erectile function was assessed by measuring intracavernous pressure (ICP), and penile tissues were harvested for immunohistologic studies.

Main Outcome Measure

The peak ICP and the area under the curve were calculated for each group. Immunohistologic studies were performed for α-smooth muscle actin and neuronal nitric oxide synthase on cross-sections of penile tissue.

Results

Rats in the HJD group demonstrate a significantly higher mean peak ICP and area under the curve compared with both CN injury groups (P = .001). Postoperative erectile function in the HJD group returned to baseline function. Preservation of α-smooth muscle actin and neuronal nitric oxide synthase was observed in the HJD group compared with the other surgical trauma groups.

Clinical Implications

Hydro-jet dissection used in an RP animal model maintains erectile function and offers a potential benefit that warrants further human studies.

Strengths & Limitations

This is a novel animal study comparing a new technology to established CN dissection techniques. This study uses an animal model, which may not completely translate to post-RP ED in humans.

Conclusion

Hydro-jet dissection of the CN during RP in an animal model is associated with significantly better postoperative erectile function when compared with other CN injury. Clinical studies are needed to further investigate the putative benefit of HJD on erectile function in patients undergoing RP.

Campbell JD, Alenezi H, DeYoung LX, et al. Hydrojet Dissection of the Cavernous Nerves Preserves Erection Function in a Radical Prostatectomy Animal Model. Sex Med 2019;7:104–110.

Caveolin-1 and MLRs: A potential target for neuronal growth and neuroplasticity after ischemic stroke

Ischemic stroke is a leading cause of morbidity and mortality worldwide. Thrombolytic therapy, the only established treatment to reduce the neurological deficits caused by ischemic stroke, is limited by time window and potential complications. Therefore, it is necessary to develop new therapeutic strategies to improve neuronal growth and neurological function following ischemic stroke. Membrane lipid rafts (MLRs) are crucial structures for neuron survival and growth signaling pathways. Caveolin-1 (Cav-1), the main scaffold protein present in MLRs, targets many neural growth proteins and promotes growth of neurons and dendrites. Targeting Cav-1 may be a promising therapeutic strategy to enhance neuroplasticity after cerebral ischemia. This review addresses the role of Cav-1 and MLRs in neuronal growth after ischemic stroke, with an emphasis on the mechanisms by which Cav-1/MLRs modulate neuroplasticity via related receptors, signaling pathways, and gene expression. We further discuss how Cav-1/MLRs may be exploited as a potential therapeutic target to restore neuroplasticity after ischemic stroke. Finally, several representative pharmacological agents known to enhance neuroplasticity are discussed in this review.

Resveratrol treatment may preserve the erectile function after radiotherapy by restoring antioxidant defence mechanisms, SIRT1 and NOS protein expressions

Radiotherapy (RT) for prostate cancer (PC) can cause erectile dysfunction (ED) by damaging neurovascular structures with oxidative stress. In this study, we evaluated the effects of resveratrol, an antioxidant, on post-RT ED. Fifty rats in five groups were evaluated; control (C), prostate-confined radiotherapy with short- and long-term vehicle or resveratrol treatment. Cavernosal tissues were obtained to analyze glutathione (GSH), nitric oxide (NO), cyclic guanosine monophosphate (cGMP), 8-hydroxy-2'-deoxy-guanosine (8-OHdG) levels and superoxide dismutase (SOD), caspase-3 activities, sirtuin-1, Foxo-3, nNOS, and eNOS protein expressions. Intracavernosal pressures (ICP) were measured for the long-term treatment group. In the RT + long-term vehicle treatment group, tissue GSH, NO, cGMP, and SOD activity were decreased while 8-OHdg levels and caspase-3 activities were increased. Radiotherapy caused a decrease in sirtuin-1, nNOS, and eNOS protein expressions. These parameters were reversed by resveratrol treatment. Foxo-3 protein expressions were unaltered in the RT + short-term vehicle treatment group and started to increase as a defense mechanism in the RT + long-term vehicle group; however, resveratrol treatment caused a significant increase in Foxo-3 expressions. Resveratrol preserved the metabolic pathways involved in erectile function and provided functional protection. Resveratrol can be used as a supplementary agent in patients undergoing radiotherapy to preserve erectile function.

Understanding the cellular basis and pathophysiology of Peyronie's disease to optimize treatment for erectile dysfunction

Erectile dysfunction (ED) is a common condition that significantly impacts a man’s physical and psychological well-being. ED is often associated with Peyronie’s disease (PD), which is an abnormal curvature of the penis. Delayed treatment of or surgical invention for PD often results in ED and therefore unsatisfied patients. The pathophysiology of PD is incompletely understood, but has been studied extensively and based on our current understanding of PD physiology, many medical treatment options have been proposed. In this paper, we will review what is known about the pathophysiology of PD and the medical treatment options that have been trialed as a result. More investigations in regards to the basic science of PD need to be carried out in order to elucidate the exact mechanisms of the fibrosis, and propose new, more successful treatment options which should be implemented prior to the onset of ED.