Botanical Medicine and Natural Products Used for Erectile Dysfunction

Inhibition of erectile dysfunction-related enzymes by ginger (Zingiber officinale)-derived compounds: molecular docking and dynamics studies

Erectile dysfunction (ED) is one of the common forms of sexual disorder that significantly impacts the psychosocial quality of life amongst male folks. Previous studies have evidenced the role of arginase-1 (Arg-1), angiotensin-I-converting enzyme (ACE), phosphodiesterase-5 (PDE-5) and acetylcholinesterase (AChE) in the progression of this pathology. In the current investigation, a library of compounds present in Zingiber officinale was screened to discover lead therapeutic agents for potential inhibitors of these metabolic enzymes. The compounds were subjected to molecular docking analysis with the various proteins' standard inhibitors. Subsequently, the thermodynamic stability of the protein-ligand complexes of two top-docked compounds with the highest binding affinities for each protein was studied further via molecular dynamics (MD) using the CHARMM-GUI website. Moreover, the Absorption-Distribution-Metabolism-Excretion-Toxicity (ADMET) pharmacological properties and drug-likeness of the top-docked 5 compounds from the plant were investigated with the SuperPred and the SwissADME web servers. From the compounds' library, diacetoxy-6-gingerdiol, 10-gingerdione, alloaromadendrene, valencene, and 6-gingerdiol showed the strongest inhibitory capacities with the amino acids present at the catalytic pocket of the selected proteins. Nonetheless, valencene and alloaromadendrene displayed better stability with the various protein complexes. Given that all these compounds were predicted to be non-toxic and have acceptable drug-likeness profiles, this investigation revealed their potential as a source of lead phytochemicals from regularly consumed food substances to mitigate the pathophysiology of erectile dysfunction. However, additional lab-based experiments are required before these phytochemicals can be developed into clinically approved commercially available drugs.

Ex-vivo antioxidant, enzyme inhibitory properties and computational analysis unveil the molecular mechanism of cardiac and penile phosphodiesterase-5 inhibition by bacterial strain HOKA1 extract as an aphrodisiac's agent

The study uses in-vitro antioxidant, ex-vivo enzyme kinetics and in-silico approach using standard protocols to understand their inhibitory mechanism better. The study revealed that bacterial strain HOKA1 isolated from Oniru beach, grown in nutrient agar supplemented with sodium chloride (30%NaCl). Moreso, the bacterial strain HOKA1 extract showed better antioxidant capability and greatly reduced the penile and cardiac cGMP with the highest penile and cardiac concentration between 0.013 and 0.183 μM/Min as compared to the sildenafil citrate (0.00-0.203 μM/Min). Moreover, the kinetic parameters (Vmax and Km) effects revealed that bacterial strain HOKA1 extract inhibited PDE-5 activities better than sildenafil citrate. The GC-MS analysis revealed twenty-nine bioactive compounds in the extract, and these compounds could provide comprehensible supporting evidence for the antioxidant and inhibitory potential of the strain HOKA1 extract on PDE-5 activity. Molecular docking study revealed majority of the GC-MS-identified bioactive constituents from the HOKA1 extract showed high binding energy or lower bonding affinities (-6.8 to -3.3 kcal/mol) compared to reference drug sildenafil citrate (-9.6 kcal/mol), except campesterol (-10.0 kcal/mol); also, ergostane (-9.9 kcal/mol). The results of 100 ns simulation (RMSF, RMSD, Rg and H-bond) show extraordinary stability of PDE-5 with campesterol and ergostane, so also complimentary binding energy of MM-PBSA (campesterol -65.92±4.09 kcal/mol; ergostane -57.23±4.70 kcal/mol) indicating their probability of acting promising PDE-5 inhibitors. Therefore, the study revealed that bacterial strain HOKA1 extract showed a better aphrodisiac property, and its bioactive compounds (campesterol and ergostane) should be considered in upcoming rational development and design of more active selective PDE-5 inhibitors, making a treatment for erectile dysfunction.

Carvacrol prevents D-( +)-galactose-induced aging-associated erectile dysfunction by improving endothelial dysfunction and oxidative stress in rats

Aging is one of the risk factors involved in the development of erectile dysfunction (ED). Growing evidence suggests that oxidative stress is the critical mediator of changes in endothelial function and penile vascular tone in the aging process. Thus, reducing reactive oxygen species (ROS) levels may preserve the bioactivity of the penile vasculature. Antioxidant compounds, such as carvacrol, limit the damage caused by ROS and, therefore, benefit the treatment of ED. Thus, this study aims to evaluate the effects of carvacrol on ED using the D-( +)-galactose aging model. The animals were divided into five groups: control, D-( +)-galactose 150 mg/kg, carvacrol 50 mg/kg or 100 mg/kg, and sildenafil 1.5 mg/kg treated daily for 8 weeks. The physiological, functional, and morphological characteristics of aging-associated ED were evaluated after treatment with carvacrol. Carvacrol prevented ED in a D-( +)-galactose-induced aging model by reducing hypercontractility, enhancing endothelial dysfunction in the rat corpus cavernosum, and improving endothelial health of rat cavernous endothelial cells. In addition, carvacrol prevented the destruction of erectile components essential for penile erection and promoted a reduction of penile tissue senescence, probably through mechanisms that involve the harmful modulation of oxidative stress. Carvacrol significantly improved the erectile function of rats in a D-( +)-galactose-induced aging model and has excellent potential as a new therapeutic alternative in treating erectile dysfunction.

Recent progress on Prangos (Apiaceae) species used in traditional herbal medicine

ETHNOPHARMACOLOGICAL RELEVANCE

Plants have been used for a long time in traditional medicine to treat many diseases. The genus Prangos belongs to the Apiaceae family and has various medicinal and aromatic species. Since ancient times, Prangos species have been employed extensively in traditional medicine for different purposes and are especially popular for their aphrodisiac effects.

AIM OF THE REVIEW

The goal of this paper is to represent a systematic review of the species in the genus Prangos, including their botanical characteristics, uses in traditional medicine, phytochemical constituents, the composition of the essential oils produced, and the biological properties.

MATERIALS AND METHODS

The articles regarding traditional uses and bioactivities of Prangos species were evaluated using electronic databases such as PubMed, Google Scholar, and ScienceDirect. Use of the World Flora Online (WFO) - The Plant List, The International Plant Names Index, the World Checklist of Vascular Plants (2024), and ChemDraw Professional helped complete this compilation.

RESULTS

Phytochemical investigations have indicated that coumarins are characteristic constituents of Prangos species, especially prenylated simple coumarins and furanocoumarins, and also flavonoids, terpenoids, and phytosterols occur in this genus. In addition, the essential oils of these plants have been examined. The biological properties of the Prangos species seem worthy of further investigation. Also, some information about the toxicity of these species and their use as ingredients in food products is presented.

CONCLUSIONS

This review highlights the evaluation of traditional knowledge, phytochemical profiles, biological activities, and potential uses of Prangos species as foods and spices. Many pharmacological activities have been performed related to their traditional uses, but frequently, the exact mechanism of action remains scientifically unproven. This review has compiled data on the phytochemistry, the active secondary metabolites, the biological properties, and recent advances in Prangos species.

Exploring natural herbs: their role in treating male infertility, enhancing sexual desire and addressing urological disorders

Infertility affects 8-12% of couples globally, with male factors contributing to around 40% of cases. Common male infertility issues include erectile dysfunction (ED) and low sperm count or quality, which account for over 90% of cases. These problems often result from anatomical, hormonal, or genetic abnormalities. This review focuses on natural aphrodisiac herbs commonly used to address ED, providing detailed information on their botanical characteristics, metabolic pathways, recommended dosages, phytochemical properties, side effects, origins, and traditional uses. It also reviews recent studies on medicinal herbs that boost sexual desire and treat urological conditions. By compiling reliable findings from the past decade, the study aims to serve as a comprehensive resource for individuals dealing with sexual health issues. Through careful evaluation of each herb, it offers insights into their effectiveness and limitations, emphasizing the potential of natural treatments as complementary alternatives to conventional therapies for male infertility and related conditions.

Isoliquiritigenin: a potential drug candidate for the management of erectile dysfunction

OBJECTIVE

This study aimed to assess the erectogenic properties of isoliquiritigenin taking sildenafil (SDF) as the standard.

METHODS

The binding affinity of isoliquiritigenin (ISL) with the erectile marker proteins (endothelial nitric oxide synthase [eNOS] and enzyme phosphodiesterase type 5 [PDE5]) was investigated using Autodock Vina, which was validated using molecular dynamics simulation. Furthermore, the effect of ISL on the eNOS and PDE5 messenger ribonucleic acid (mRNA) expression and the sexual behavior of mice was investigated, along with the assessment of the pharmacokinetics of ISL.

KEY FINDINGS

The results revealed that the binding affinity of ISL-eNOS/PDE5 and SDF-eNOS/PDE5 was in the range of -7.5 to -8.6 kcal/mol. The ISL-eNOS/PDE5 complexes remained stable throughout the 100 ns simulation period. Root mean square deviation, Rg, SASA, hydrogen, and hydrophobic interactions were similar between ISL-eNOS/PDE5 and SDF-eNOS/PDE5. Analysis of mRNA expressions in paroxetine (PRX)-induced ED mice showed that the co-administration of PRX with ISL reduced PDE5 and increased eNOS mRNA expression, similar to the co-administered group (PRX+SDF). The sexual behavior study revealed that the results of PRX+ISL were better than those of the PRX+SDF group. Pharmacokinetic evaluation further demonstrated that ISL possesses drug-like properties.

CONCLUSIONS

The results showed that ISL is equally potent as SDF in terms of binding affinity, specific pharmacological properties, and modulating sexual behavior.

The Effect of the Combination of Ginseng, Tribulus Terrestris, and L-arginine on the Sexual Performance of Men with Erectile Dysfunction: a randomized, double-blind, parallel, and placebo-controlled clinical trial

Objectives

Nitric oxide is the most important mediator of penile erection after the onset of sexual excitement. It activates cyclic guanosine monophosphate (cGMP), increasing penile blood flow. Most pharmaceutical medications prevent enzyme phosphodiesterase type 5 (PDE-5) from breaking down cGMP, thus keeping its level high. However, due to the adverse effects of pharmacological therapies, herbal drugs that improve sexual function have gained attention recently. This study aimed to investigate the combined effects of ginseng, Tribulus terrestris, and L-arginine amino acid on the sexual performance of individuals with erectile dysfunction (ED) using the 5-item version of the International Index of Erectile Function (IIEF-5) questionnaire.

Methods

Over three months, 98 men with erectile dysfunction were randomly assigned to receive either 500 mg of herbal supplements or placebo pills. Each herbal tablet contained 100 mg of protodioscin, 35 mg of ginsenosides, and 250 mg of L-arginine.

Results

The results showed that the changes in the average scores of ILEF-5 within each group before and after the intervention indicated that all parameters related to the improvement of sexual function in patients with erectile dysfunction improved in the herbal treatment group (p < 0.001). The herbal group significantly improved IIEF-5 scores in non-diabetics (p < 0.05). However, there was no significant difference in the changes of IIEF-5 scores between the two intervention and control groups in diabetic patients.

Conclusion

In conclusion, ginseng, Tribulus terrestris, and L-arginine have properties that increase energy and strengthen sexual function, making them suitable for patients with sexual disorders.

Beneficial effect of honokiol and magnolol on polyol pathway and oxidative stress parameters in the testes of diabetic rats

In diabetes hyperglycemia, excessive production of free radicals and present oxidative stress lead to many complications in the body, including male reproductive system disorders. To prevent the development of diabetic complications in the testes resulting from them, it seems beneficial to include compounds considered as natural antioxidants. Honokiol and magnolol are neolignans obtained from magnolia bark, which possess proven antioxidant properties. The aim of this study was to evaluate the effect of honokiol and magnolol on the parameters of oxidative stress, polyol pathway and glycation products in the testes as well as on selected biochemical parameters in the blood serum of rats with type 2 diabetes. The study was conducted on mature male Wistar rats with high fat diet and streptozotocin-induced type 2 diabetes. Neolignans-treated rats received honokiol or magnolol orally at the doses of 5 or 25 mg/kg, respectively, for 4 weeks. Parameters related to glucose and lipid homeostasis, basic serological parameters and sex hormones level in the serum as well as polyol pathway parameters, antioxidant enzyme activity, endogenous antioxidants level, sumaric parameters for oxidative stress and oxidative damage in the testes were estimated. Oral administration of honokiol and magnolol turned out to be beneficial in combating the effects of oxidative stess in the testes, but showed no favorable effects on serum biochemical parameters. Additionally, magnolol compared to honokiol revealed more advantageous impact indicating the reversal of the effects of diabetic complications in the male reproductive system and counteracted oxidative stress damages and polyol pathway disorders in the testes.

UPLC-Q-TOF-MS profiling of Viola stocksii Boiss. and evaluation of aphrodisiac potential and risk factors associated with erectile dysfunction

ETHNOPHARMACOLOGICAL RELEVANCE

Viola stocksii Boiss. locally known as makhni or makhanr booti, is an important medicinal food plant with multiple therapeutic applications, including erectile dysfunction (ED). It is mixed with butter and used for boosting energy and sexual health in the subcontinent.

AIMS OF THE STUDY

This study was designed to evaluate the chemical composition, aphrodisiac potential and effect of V. stocksii on the risk factors associated with ED.

METHODOLOGY

The hydroethanolic extract of V. stocksii (HEEVS) was prepared through the microwave-assisted extraction (MAE) technique. The chemical composition was evaluated using preliminary phytochemical screening and UPLC-Q-TOF-MS analysis. Metals and minerals analysis was performed by an atomic absorption spectrophotometer. The aphrodisiac activity of HEEVS was evaluated using an in vivo aphrodisiac model established in male albino rats and the effect on various sexual parameters such as mount, intromission, ejaculation frequencies and mount, intromission, ejaculation latencies, postejaculatory interval, penile reflexes and serum hormone concentration were analyzed. The effect of HEEVS on various risk factors associated with ED, including prostate cancer (PC), bacterial infections, diabetes and obesity, was evaluated using various in vitro assays. Moreover, four compounds were selected from the UPLC-Q-TOF-MS profile and evaluated for in silico computational analysis against phosphodiesterase-5 (PDE-5) for possible interaction.

FINDINGS

The phytochemical screening revealed the presence of various secondary metabolites in HEEVS, while 58 compounds were tentatively identified in the UPLC-Q-TOF-MS analysis. Various important minerals and metals such as zinc, calcium, cadmium and magnesium were detected in the atomic absorption spectrometry analysis. The in vivo aphrodisiac evaluation showed a significant (p < 0.05) increase in the mount, intromission and ejaculation frequencies and a decrease in the mount, intromission latencies and post-ejaculatory intervals at a dose of 300 mg/kg. A marked (p < 0.05) increase was observed in the concentration of serum testosterone and luteinizing hormones in HEEVS treated animals with a significant increase in total penile reflexes. The extract displayed significant anti-prostate cancer activity and a potential antibacterial spectrum against E. coli and S. aureus, with MIC50 values of 215.72 μg/mL and 139.05 μg/mL, respectively. Similarly, HEEVS was found active towards pancreatic lipase (67.34 ± 1.03%), α-glucosidase (3.87 ± 0.54 mmol ACAE/g d.w.) and α-amylase (6.98 ± 1.63 mmol ACAE/g d.w.). The in silico docking study presented a potential interaction between the selected compounds and residues of the active site of PDE-5.

CONCLUSION

This report highlights the aphrodisiac potential of V. stocksii and provides experimental support for its traditional use in ED with an attenuative effect on the risk factors associated with ED. Moreover, the chemical composition displayed the presence of functional phytoconstituents and minerals in HEEVS and paves the way for the isolation of compounds with potent aphrodisiac activity.

Biological activities of African medicinal plants in the treatment of erectile dysfunction: a mechanistic perspective

The global incidence of erectile dysfunction is increasingly becoming a significant health concern, as its frequency demonstrates a consistent upward trajectory each year. In recent years, FDA-approved drugs like sildenafil among others has been approved to treat this disorder however the drug is not without its own side effects. In a bid to develop alternative therapeutic option, scientists have now turned to traditional medicine in search of a treatment regimen. Africa is blessed with numerous medicinal plants used in the treatment and management of several diseases including erectile dysfunction. Due to limited access to modern medicine and high-quality medical facilities, a significant number of individuals in Africa continue to depend on traditional medicine as a means of addressing critical health issues. Perhaps one of the grossly explored medicinal properties of plants in Africa is for erectile function. Through years of extensive research in medicinal plants, several plants indigenous to Africa have been identified to show profound ability to mitigate erectile dysfunction. While previous reports have indeed corroborated the ability of this plant to abate erectile dysfunction, there is still a dearth of information regarding the mechanistic aspect of these plants. Hence, the current review aims to provide a comprehensive mechanistic perspective to the major African medicinal plant which have been reported to be effective in the treatment of erectile dysfunction.

Efficacy and safety assessment of traditional Chinese medicine for erectile dysfunction: A meta-analysis and trial sequential analysis

BACKGROUND

Several patients with erectile dysfunction do not accept or benefit from conventional therapy with phosphodiesterase type 5 inhibitors; thus, alternative and complementary therapies are in need. Traditional Chinese medicine has been treating erectile dysfunction in China, but its clinical value is inconclusive.

OBJECTIVE

To systematically evaluate the efficacy and safety of traditional Chinese medicine in treating erectile dysfunction.

METHODS

Randomized controlled trials were retrieved from a comprehensive search in the literature published in the past decade from the Web of Science, PubMed, Embase, Cochrane Library, SinoMed, China National Knowledge Internet, WanFang, and VIP. We performed a meta-analysis of the International Index of Erectile Function 5 questionnaire scores, clinical recovery rates, and testosterone levels using Review Manager 5.4 software. The trial sequential analysis was conducted to check the results.

RESULTS

A total of 45 trials with 5016 patients were included. Meta-analysis results showed that traditional Chinese medicine effectively improved the International Index of Erectile Function 5 questionnaire scores (weighted mean difference = 3.78, 95% confidence interval: 3.12, 4.44; p < 0.001), clinical recovery rates (risk ratio = 1.57, 95% confidence interval: 1.38, 1.79; p < 0.001), testosterone levels (weighted mean difference = 2.42, 95% confidence interval: 1.59, 3.25; p < 0.001) compared with the controls. The single and add-on applications of traditional Chinese medicine could improve the International Index of Erectile Function 5 questionnaire score (p < 0.001). The trial sequential analysis confirmed the robustness of the analysis of the International Index of Erectile Function 5 questionnaire scores. A significant difference in the incidence of adverse effects between the treatment and control groups was not observed (risk ratio = 0.82, 95% confidence interval: 0.65, 1.05; p = 0.12).

CONCLUSION

Traditional Chinese medicine can gain better responses in improving the International Index of Erectile Function 5 questionnaire scores, clinical recovery rates, and testosterone levels as an alternative and complementary treatment, with no increase in side effects. However, more standardized, long-term, traditional Chinese medicine and integrative therapy clinical trials are needed to support the clinical application of traditional Chinese medicine.

Traditional, Complementary and Alternative Medicines in the Treatment of Ejaculatory Disorders: A Systematic Review

Background and Objectives: Ejaculatory dysfunction (EjD) is a common male sexual disorder that includes premature ejaculation, delayed ejaculation, retrograde ejaculation, and anejaculation. Although psychological and pharmacological treatments are available, traditional, complementary, and alternative medicine (TCAM) is reportedly used. However, the clinical evidence for TCAM in EjD remains unclear. Therefore, this study aims to systematically review human clinical trials investigating the use of TCAM to treat EjD. Materials and Methods: A systematic review of the literature following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted by searching Scopus and PubMed databases. Controlled clinical trials investigating a cohort of male patients diagnosed primarily with EjD and undergoing any TCAM intervention compared to any comparison group were included. Quality of the studies was assessed using the Cochrane Risk of Bias tool for randomized controlled trials. Results: Following article screening, 22 articles were included. Of these, 21 investigated TCAM in premature ejaculation, and only 1 investigated TCAM in retrograde ejaculation. Different TCAM categories included studies that investigated lifestyle, exercise and/or physical activities (n = 7); herbal medicine supplements (n = 5); topical herbal applications (n = 4); acupuncture or electroacupuncture (n = 3); vitamin, mineral and/or nutraceutical supplements (n = 1); hyaluronic acid penile injection (n = 1); and music therapy (n = 1). Only 31.8% (n = 7) of the included studies were found to have a low risk of bias. The available studies were widely heterogenous in the TCAM intervention investigated and comparison groups used. However, the included studies generally showed improved outcomes intra-group and when compared to placebo. Conclusions: Different TCAM interventions may have an important role particularly in the management of PE. However, more studies using standardized interventions are needed.

Botanical drugs for treating erectile dysfunction: clinical evidence

Phosphodiesterase-5 inhibitors (PDE5-i) have been widely used in clinical practice for the treatment of erectile dysfunction (ED). However, due to its suboptimal therapeutic effects and side effects, it is necessary to develop new medicines for ED treatment. Botanical drugs have been widely investigated as potential ED treatment drugs and have shown promising therapeutic effects. This review summarized 34 studies, including five botanical drugs with PDE5 inhibitory activity, seven botanical drugs without PDE5 inhibitory activity, and six mixed botanical drugs. The results of clinical studies regarding the aforementioned botanical drugs and relevant mechanisms are summarized in this study. It is necessary to conduct high-quality clinical trials to verify the dosage, targeted patients and therapeutic effects, and further pharmacology experiments are also needed to identify the active compounds.

Tectorigenin: A Review of Its Sources, Pharmacology, Toxicity, and Pharmacokinetics

Tectorigenin is a well-known natural flavonoid aglycone and an active component that exists in numerous plants. Growing evidence suggests that tectorigenin has multiple pharmacological effects, such as anticancer, antidiabetic, hepatoprotective, anti-inflammatory, antioxidative, antimicrobial, cardioprotective, and neuroprotective. These pharmacological properties provide the basis for the treatment of many kinds of illnesses, including several types of cancer, diabetes, hepatic fibrosis, osteoarthritis, Alzheimer's disease, etc. The purpose of this paper is to provide a comprehensive summary and review of the sources, extraction and synthesis, pharmacological effects, toxicity, pharmacokinetics, and delivery strategy aspects of tectorigenin. Tectorigenin may exert certain cytotoxicity, which is related to the administration time and concentration. Pharmacokinetic studies have demonstrated that the main metabolic pathways in rats for tectorigenin are glucuronidation, sulfation, demethylation and methoxylation, but that it exhibits poor bioavailability. From our perspective, further research on tectorigenin should cover: exploring the pharmacological targets and mechanisms of action; finding an appropriate concentration to balance pharmacological effects and toxicity; attempting diversified delivery strategies to improve the bioavailability; and structural modification to obtain tectorigenin derivatives with higher pharmacological activity.

Ethnological validation of Ashwagandha (Withania somnifera L. Dunal) ghrita as 'Vajikarana Rasayana': In-silico, in-vitro and in-vivoapproach

ETHNOPHARMACOLOGICAL RELEVANCE

Processing cow ghee (clarified butterfat) with therapeutic herbs, i.e. ghrita, is recognized for augmenting the therapeutic efficacy of plant materials. Ashwagandha ghrita (AG) is an effective Ayurvedic formulation consisting of Indian ginseng, i.e., Withania somnifera (L.) Dunal, the main constituent used to treat infertility, weakness, gynaecological disorders, and general debility.

OBJECTIVES

The present investigation was undertaken to corroborate the ethnopharmacological claim of AG as 'Vajikarana Rasayana' for its aphrodisiac potential using bioinformatics (in-silico) and experimental (in-vitro and in-vivo) approaches.

METHODS

AG was formulated as per the methods reported in Ayurved sarsangraha. AG was further subjected to HPLC, GCMS analysis, and biological (acute toxicity and aphrodisiac) assessment per the standard procedures. Thirty-eight bioactives of Indian ginseng were subjected to computational studies (molecular docking and network pharmacology) to confirm the plausible mechanism.

RESULTS

AG was found to be safe up to 2000 mg/kg body wt., and it showed dose-dependent upsurge (p < 0.01 and p < 0.05, wherever necessary) in mount and intromission frequency, genital grooming, and anogenital sniffing at 150 and 300 mg/kg body weight suggesting aphrodisiac activity. In-vitro studies demonstrated significant relaxation of the Corpus Cavernosal Smooth Muscle at all concentrations in a dose-dependent manner. Furthermore, the results of molecular modelling studies were in agreement with the biological activity and showed interaction with phosphodiesterase-5 as a possible target.

CONCLUSION

AG exhibited an aphrodisiac effect and substantiated the traditional claim of Indian ginseng-based ghrita formulation as 'Vajikarana Rasayana'.

The Race to Replace PDE5i: Recent Advances and Interventions to Treat or Manage Erectile Dysfunction: Evidence from Patent Landscape (2016-2021)

For a few decades, globally, erectile dysfunction (ED) has become more prominent even in young adults and represents a mounting health concern causing a significant effect on men’s quality of life. There is an expectation that by the end of 2025, the number of ED cases can rise to 322 million. We aimed to comprehensively analyze the scientific output of scholarly articles and studies in the field of ED (2016–2021). Data from scholarly articles were collected using Pubmed, and clinical trials-related information was accessed from the clinical trials website. An extensive patent search was conducted using databases such as USPTO (United States patent and trademark office) and EPO (European patent office), WIPO (World Intellectual Property Organization), etc. Owing to the high market value of ED drugs, considerable interest was attained to grab the opportunities. The race to replace the phosphodiesterase type 5 inhibitor (PDE5 inhibitor-PDE5i) can be identified as evident from the significant number of patents filed and the inventions cleared with clinical trials. Some other intriguing interventions are identified for ED treatment but have yet to gain public acceptance. The current analysis confirms the overall evolution and unexplored corners of research on ED treatment strategies with a current global projection.

Nutraceuticals and Phytotherapy in Men's Health: Antioxidants, Pro-oxidants, and a Novel Opportunity for Lifestyle Changes

Patients using nutraceuticals represent a diverse patient population with a keen potential interest and/or adherence to healthy lifestyle changes. BPH nutraceuticals, including saw palmetto were as safe, but not more effective than placebo in the STEP and CAMUS clinical trials, but another high-quality saw palmetto product could be tested in a phase 3 trial. Several other BPH supplements need more recent robust clinical data, environmental oversight, or safety data. ED supplements, including Panax ginseng, and the notable nitric oxide (NO) enhancing amino acids arginine and citrulline have positive preliminary short-term efficacy data with and without PDE-5 inhibitors, but herbal quality control (QC) or safety signals with some of these agents in specific patient populations need to be resolved. "Less is more" should be the current mantra in the prostate cancer milieu, and potentially in some men with male infertility based on the FAZST trial because it is plausible some antioxidants are exhibiting prooxidant activity in some settings. Some prescription anthelmintic medications are being studied, others are being purchased over-the-counter (OTC), but their preliminary safety and efficacy against cancer have been concerning and questionable. In fairness, ongoing additional objective clinical trial data should become available soon, especially with mebendazole. DHEA or DHEA enhancing products have multiple concerns including HDL reductions, and their questionable use in men with BPH or prostate cancer based on the limited data. Some of these concerns should also be addressed in long-term robust clinical trials of prescription testosterone agents. Regardless, more attention should be directed toward heart-healthy lifestyle changes for most urologic men's health conditions, whether they are used in a preventive or synergistic setting with other acceptable clinical treatment options.

A preliminary study of the efficacy of the polyherbal preparation Sao Thong Tai for erectile dysfunction among elderly men: a double-blind, randomized controlled trial

Background

The traditional Thai polyherbal formulation “Sao Thong Tai” (STT) contains four medicinal plants, namely Boesenbergia rotunda (L.) Mansf., Sida acuta Burm.f., Dactyloctenium aegyptium (L.) Willd., and Oryza sativa L. and it is considered an aphrodisiac and remedy for the effective treatment of decreased male libido in Thai traditional medicine and it may ameliorate erectile function. This pilot study was carried out to investigate the efficacy and safety of the polyherbal STT for mild to moderate erectile dysfunction in a small group of elderly men in Thailand in a double-blind, randomized controlled trial.

Methods

This research is a preliminary study. Fifty-four elderly males aged 50-69 years who had been diagnosed with mild to moderate ED were randomized into two groups of equal size: an STT group (n=27) and a placebo control group (n=27). The patients received either an 800 mg dose of STT extract or a lactose placebo twice a day for the eight-week treatment period, after which they were followed up for four weeks. Erectile function, sexual activity, self-reported attitudes toward sexual dysfunction, and partner-reported sexual dysfunction were investigated to confirm the efficacy of the polyherbal preparation. The International Index of Erectile Function (IIEF-5) and the Scale for Quality of Sexual Function (QSF) were used for primary outcome assessment.

Results

The IIEF-5 scores of the STT group were significantly increased compared with those of the placebo group (p<0.001). The severity of ED decreased from "mild" or "mild to moderate" to normal in 88.9% of the STT group vs. 0% of the placebo group, and the QSF score increased in the STT group (p<0.001). Sexual activity, self-reported views of sexual dysfunction, and partners’ views of sexual dysfunction showed significant improvement in the STT group, and there was no significant difference in psychosomatic quality of life. No adverse events were observed in either group.

Conclusion

Compared with a placebo, an oral aqueous extract of STT taken daily at a dose of 1,600 mg for eight weeks can effectively treat mild to moderate ED in elderly men. The preparation was also shown to be safe with respect to all parameters assessed. This finding demonstrates that STT can be used for the effective treatment of decreased male libido in Thai traditional medicine and may ameliorate ED.

Trial registration

TCTR/20180126001 033/2560. Registered 16 January 2018, Thai Clinical Trials Registry http://www.thaiclinicaltrials.org/

Molecular Action of Herbal Medicine in Physiology of Erection and its Dysfunction

Erection is a physiological process that involves vascular, hormonal, and nervous factors. Erectile dysfunction is one of the male sexual problems that occur globally and is reported to affect men's quality of life. Herbal plants have been widely used for disease treatment, including the problem of erectile dysfunction. This paper aims to review the molecular potential of various plants in the physiology of erection and to treat erectile dysfunction. The literature search was carried out through the Pubmed and Google Scholar databases regarding the molecular mechanisms of herbal plants and their potential involvement in the physiology of erection and overcoming erectile dysfunction. This paper focuses on six herbal plants: Panax ginseng, Ginkgo biloba, Epimedium, Black pepper, Tribulus terrestris, and Eurycoma longifolia. The six herbal plants have involvement in the erection process and have molecular potential in the treatment of erectile problems

Evaluation of the Effect on Sexual Performance of a Nutraceutical Combination Containing Alpha Lipoic Acid, Vitis vinifera L. and Ginkgo biloba, Compared to Placebo, Avanafil or a Combination of Nutraceutical Plus Avanafil in Males With Type 2 Diabetes Mellitus With Erectile Dysfunction

AIM

To evaluate if therapy with a nutraceutical combination of alpha lipoic acid, Vitis vinifera L. and Ginkgo biloba (Blunorm forte^®) can be helpful and be synergic with Avanafil.

METHODS

The trial included 123 males with type 2 diabetic mellitus and with erectile dysfunction (ED), aged ≥18 years. Patients were divided in four different arms: 1^st arm: placebo during the three months of treatment and before sexual act; 2^nd arm: placebo for three months and Avanafil: 1 tablet, 200 mg, 15-30 minutes before sexual act; 3^rd arm: Blunorm forte: 1 tablet, 40 minutes before the meal (breakfast) during the three months and Avanafil: 1 tablet, 200 mg, 15-30 minutes before sexual act; 4^th arm: Blunorm forte: 1 tablet, 40 minutes before the meal (breakfast and dinner) during the three months and placebo 15-30 minutes before sexual act.

RESULTS

A significant reduction of fasting plasma glucose, and homeostasis model assessment-insulin resistance index were recorded both in Avanafil + Blunorm forte and with Blunorm forte. Metalloproteinases-2, and -9 were reduced in the Avanafil + Blunorm forte group. High sensitivity-C-reactive protein was decreased by both Avanafil, and Avanafil + Blunorm forte group. No variations were recorded with the other treatments. The group treated with Blunorm forte and Avanafil reached a higher International Index of Erectile Function (IIEF) score after 3 months of therapy compared to baseline and placebo and compared to Avanafil and Blunorm forte taken alone.

CONCLUSION

Blunorm forte^® can be helpful and synergic with Avanafil in increasing sexual performance compared to placebo.

Pathological Significance of Macrophages in Erectile Dysfunction Including Peyronie's Disease

Erectile function is regulated by complex mechanisms centered on vascular- and nerve-related systems. Hence, dysregulation of these systems leads to erectile dysfunction (ED), which causes mental distress and decreases the quality of life of patients and their partners. At the molecular level, many factors, such as fibrosis, lipid metabolism abnormalities, the immune system, and stem cells, play crucial roles in the etiology and development of ED. Although phosphodiesterase type 5 (PDE5) inhibitors are currently the standard treatment agents for patients with ED, they are effective only in a subgroup of patients. Therefore, further insight into the pathological mechanism underlying ED is needed to discuss ED treatment strategies. In this review, we focused on the biological and pathological significance of macrophages in ED because the interaction of macrophages with ED-related mechanisms have not been well explored, despite their important roles in vasculogenic and neurogenic diseases. Furthermore, we examined the pathological significance of macrophages in Peyronie’s disease (PD), a cause of ED characterized by penile deformation (visible curvature) during erection and pain. Although microinjury and the subsequent abnormal healing process of the tunica albuginea are known to be important processes in this disease, the detailed etiology and pathophysiology of PD are not fully understood. This is the first review on the pathological role of macrophages in PD.

Alternative medicine and herbal remedies in the treatment of erectile dysfunction: A systematic review

Objectives: To systematically review and discuss the current evidence from placebo-controlled clinical trials that investigated the use of alternative medicines and herbal remedies in the management of erectile dysfunction (ED). Methods: A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-based systematic review using specific keyword combinations was conducted on the PubMed and Scopus databases. Randomised controlled trials investigating herbal medicine in at least one group and using the International Index of Erectile Function (IIEF) as an outcome in patients primarily diagnosed with ED were included for review. Results: Following the literature search, screening and eligibility analysis, a total of 42 articles were included. The 42 articles were categorised as single herb extractions (n = 14), combination herbal formula (n = 5), combination of herbal formula and non-herbal nutraceuticals (n = 7), non-herbal nutraceuticals (n = 5), acupuncture and moxibustion (n = 2), diet and nutrition (n = 3), exercise (n = 5), and topical treatments (n = 1). Based on the results, Korean ginseng, Pygnogenol and Prelox, Tribulus terrestris, Lepidium meyenii, L-arginine, acupuncture and lifestyle interventions were the more predominantly investigated treatments interventions for ED. Conclusions: Panax ginseng, Pygnogenol, Prelox and Tribulus terrestris have promising evidence as herbal products, alongside L-arginine as a nutritional supplement, for ED based on IIEF outcomes, and warrant further clinical investigation. The mechanisms of action remain unclear, but each of these appears to in part increase nitric oxide synthesis. Importantly, improved diet and exercise should be considered, particularly in patients with obesity or diabetes mellitus.

Development of Phosphodiesterase-Protein-Kinase Complexes as Novel Targets for Discovery of Inhibitors with Enhanced Specificity

Phosphodiesterases (PDEs) hydrolyze cyclic nucleotides to modulate multiple signaling events in cells. PDEs are recognized to actively associate with cyclic nucleotide receptors (protein kinases, PKs) in larger macromolecular assemblies referred to as signalosomes. Complexation of PDEs with PKs generates an expanded active site that enhances PDE activity. This facilitates signalosome-associated PDEs to preferentially catalyze active hydrolysis of cyclic nucleotides bound to PKs and aid in signal termination. PDEs are important drug targets, and current strategies for inhibitor discovery are based entirely on targeting conserved PDE catalytic domains. This often results in inhibitors with cross-reactivity amongst closely related PDEs and attendant unwanted side effects. Here, our approach targeted PDE–PK complexes as they would occur in signalosomes, thereby offering greater specificity. Our developed fluorescence polarization assay was adapted to identify inhibitors that block cyclic nucleotide pockets in PDE–PK complexes in one mode and disrupt protein-protein interactions between PDEs and PKs in a second mode. We tested this approach with three different systems—cAMP-specific PDE8–PKAR, cGMP-specific PDE5–PKG, and dual-specificity RegA–R_D complexes—and ranked inhibitors according to their inhibition potency. Targeting PDE–PK complexes offers biochemical tools for describing the exquisite specificity of cyclic nucleotide signaling networks in cells.