Clinical assessment of a supplement of Pycnogenol® and L-arginine in Japanese patients with mild to moderate erectile dysfunction

Efficacy of L-arginine and Pycnogenol ® in the treatment of male erectile dysfunction: a systematic review and meta-analysis

Background

The objective of this meta-analysis was to review clinical trials of the combination of Pycnogenol ® and L-arginine (PAL) in the treatment of erectile dysfunction in men and to observe the effect of PAL combined therapy on sexual function in patients with erectile dysfunction (ED), and we hope to provide more choices of drugs for treating patients with ED.

Methods and analysis

The study was constructed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. We searched seven databases from inception to 15 February 2023, for a comprehensive search of clinical trials using relevant keywords. Continuous variables in this meta-analysis were calculated using the mean difference and 95% confidence interval. All relevant statistical analyses were performed using RevMan v. 5.4 software.

Results

Three studies with 184 patients were included in the present meta-analysis. There were no significant differences in the basic characteristics of the included studies. The results of the current meta-analysis showed that there were significant differences in the international index of erectile function scores (erectile domain), intercourse satisfaction scores, orgasmic function scores, overall satisfaction scores, and sexual desire scores between the combination treatment group and the control group. There was no significant difference in improving the testosterone levels between the two groups.

Conclusion

These results indicate that the combination of PAL may have a significant effect on improving sexual function in patients with mild to moderate ED. This study will provide clinicians with more options for treating patients with ED. More randomized controlled trials are needed in the future to further demonstrate the effect of combination therapy on sexual function in patients with ED.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/#myprosperoUnique, Identifier: CRD42023411781.

Clozapine's multiple cellular mechanisms: What do we know after more than fifty years? A systematic review and critical assessment of translational mechanisms relevant for innovative strategies in treatment-resistant schizophrenia

Almost fifty years after its first introduction into clinical care, clozapine remains the only evidence-based pharmacological option for treatment-resistant schizophrenia (TRS), which affects approximately 30% of patients with schizophrenia. Despite the long-time experience with clozapine, the specific mechanism of action (MOA) responsible for its superior efficacy among antipsychotics is still elusive, both at the receptor and intracellular signaling level. This systematic review is aimed at critically assessing the role and specific relevance of clozapine's multimodal actions, dissecting those mechanisms that under a translational perspective could shed light on molecular targets worth to be considered for further innovative antipsychotic development. In vivo and in vitro preclinical findings, supported by innovative techniques and methods, together with pharmacogenomic and in vivo functional studies, point to multiple and possibly overlapping MOAs. To better explore this crucial issue, the specific affinity for 5-HT₂R, D1R, α_2c, and muscarinic receptors, the relatively low occupancy at dopamine D2R, the interaction with receptor dimers, as well as the potential confounder effects resulting in biased ligand action, and lastly, the role of the moiety responsible for lipophilic and alkaline features of clozapine are highlighted. Finally, the role of transcription and protein changes at the synaptic level, and the possibility that clozapine can directly impact synaptic architecture are addressed. Although clozapine's exact MOAs that contribute to its unique efficacy and some of its severe adverse effects have not been fully understood, relevant information can be gleaned from recent mechanistic understandings that may help design much needed additional therapeutic strategies for TRS.

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.

Pine bark (Pinus spp.) extract for treating chronic disorders

BACKGROUND

Pine bark (Pinus spp.) extract is rich in bioflavonoids, predominantly proanthocyanidins, which are antioxidants. Commercially-available extract supplements are marketed for preventing or treating various chronic conditions associated with oxidative stress. This is an update of a previously published review.

OBJECTIVES

To assess the efficacy and safety of pine bark extract supplements for treating chronic disorders.

SEARCH METHODS

We searched three databases and three trial registries; latest search: 30 September 2019. We contacted the manufacturers of pine bark extracts to identify additional studies and hand-searched bibliographies of included studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) evaluating pine bark extract supplements in adults or children with any chronic disorder.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility, extracted data and assessed risk of bias. Where possible, we pooled data in meta-analyses. We used GRADE to evaluate the certainty of evidence. Primary outcomes were participant- and investigator-reported clinical outcomes directly related to each disorder and all-cause mortality. We also assessed adverse events and biomarkers of oxidative stress.

MAIN RESULTS

This review included 27 RCTs (22 parallel and five cross-over designs; 1641 participants) evaluating pine bark extract supplements across 10 chronic disorders: asthma (two studies; 86 participants); attention deficit hyperactivity disorder (ADHD) (one study; 61 participants), cardiovascular disease (CVD) and risk factors (seven studies; 338 participants), chronic venous insufficiency (CVI) (two studies; 60 participants), diabetes mellitus (DM) (six studies; 339 participants), erectile dysfunction (three studies; 277 participants), female sexual dysfunction (one study; 83 participants), osteoarthritis (three studies; 293 participants), osteopenia (one study; 44 participants) and traumatic brain injury (one study; 60 participants). Two studies exclusively recruited children; the remainder recruited adults. Trials lasted between four weeks and six months. Placebo was the control in 24 studies. Overall risk of bias was low for four, high for one and unclear for 22 studies. In adults with asthma, we do not know whether pine bark extract increases change in forced expiratory volume in one second (FEV₁) % predicted/forced vital capacity (FVC) (mean difference (MD) 7.70, 95% confidence interval (CI) 3.19 to 12.21; one study; 44 participants; very low-certainty evidence), increases change in FEV₁ % predicted (MD 7.00, 95% CI 0.10 to 13.90; one study; 44 participants; very low-certainty evidence), improves asthma symptoms (risk ratio (RR) 1.85, 95% CI 1.32 to 2.58; one study; 60 participants; very low-certainty evidence) or increases the number of people able to stop using albuterol inhalers (RR 6.00, 95% CI 1.97 to 18.25; one study; 60 participants; very low-certainty evidence). In children with ADHD, we do not know whether pine bark extract decreases inattention and hyperactivity assessed by parent- and teacher-rating scales (narrative synthesis; one study; 57 participants; very low-certainty evidence) or increases the change in visual-motoric coordination and concentration (MD 3.37, 95% CI 2.41 to 4.33; one study; 57 participants; very low-certainty evidence). In participants with CVD, we do not know whether pine bark extract decreases diastolic blood pressure (MD -3.00 mm Hg, 95% CI -4.51 to -1.49; one study; 61 participants; very low-certainty evidence); increases HDL cholesterol (MD 0.05 mmol/L, 95% CI -0.01 to 0.11; one study; 61 participants; very low-certainty evidence) or decreases LDL cholesterol (MD -0.03 mmol/L, 95% CI -0.05 to 0.00; one study; 61 participants; very low-certainty evidence). In participants with CVI, we do not know whether pine bark extract decreases pain scores (MD -0.59, 95% CI -1.02 to -0.16; one study; 40 participants; very low-certainty evidence), increases the disappearance of pain (RR 25.0, 95% CI 1.58 to 395.48; one study; 40 participants; very low-certainty evidence) or increases physician-judged treatment efficacy (RR 4.75, 95% CI 1.97 to 11.48; 1 study; 40 participants; very low-certainty evidence). In type 2 DM, we do not know whether pine bark extract leads to a greater reduction in fasting blood glucose (MD 1.0 mmol/L, 95% CI 0.91 to 1.09; one study; 48 participants;very low-certainty evidence) or decreases HbA1c (MD -0.90 %, 95% CI -1.78 to -0.02; 1 study; 48 participants; very low-certainty evidence). In a mixed group of participants with type 1 and type 2 DM we do not know whether pine bark extract decreases HbA1c (MD -0.20 %, 95% CI -1.83 to 1.43; one study; 67 participants; very low-certainty evidence). In men with erectile dysfunction, we do not know whether pine bark extract supplements increase International Index of Erectile Function-5 scores (not pooled; two studies; 147 participants; very low-certainty evidence). In women with sexual dysfunction, we do not know whether pine bark extract increases satisfaction as measured by the Female Sexual Function Index (MD 5.10, 95% CI 3.49 to 6.71; one study; 75 participants; very low-certainty evidence) or leads to a greater reduction of pain scores (MD 4.30, 95% CI 2.69 to 5.91; one study; 75 participants; very low-certainty evidence). In adults with osteoarthritis of the knee, we do not know whether pine bark extract decreases composite Western Ontario and McMaster Universities Osteoarthritis Index scores (MD -730.00, 95% CI -1011.95 to -448.05; one study; 37 participants; very low-certainty evidence) or the use of non-steroidal anti-inflammatory medication (MD -18.30, 95% CI -25.14 to -11.46; one study; 35 participants; very low-certainty evidence). We do not know whether pine bark extract increases bone alkaline phosphatase in post-menopausal women with osteopenia (MD 1.16 ug/L, 95% CI -2.37 to 4.69; one study; 40 participants; very low-certainty evidence). In individuals with traumatic brain injury, we do not know whether pine bark extract decreases cognitive failure scores (MD -2.24, 95% CI -11.17 to 6.69; one study; 56 participants; very low-certainty evidence) or post-concussion symptoms (MD -0.76, 95% CI -5.39 to 3.87; one study; 56 participants; very low-certainty evidence). For most comparisons, studies did not report outcomes of hospital admissions or serious adverse events.

AUTHORS' CONCLUSIONS

Small sample sizes, limited numbers of RCTs per condition, variation in outcome measures, and poor reporting of the included RCTs mean no definitive conclusions regarding the efficacy or safety of pine bark extract supplements are possible.

Assessing the Efficacy and Mechanisms of Pycnogenol® on Cognitive Aging From In Vitro Animal and Human Studies

Brain aging is a complex and multifactorial process broadly involving changes in the brain's structure, neuronal activity, and biochemical profile. These changes in brain function have also been linked to age-associated variations in cognitive function. Recent research has suggested a role of increased oxidative stress and reduced cognition in older people. Therefore, studies that examine the effects of antioxidants on cognitive performance are important, particularly in the context of an increase in elderly populations in most Western countries. One such antioxidant, Pycnogenol, is a standardized plant-based extract obtained from the bark of the French maritime pine and has a long historical use to treat inflammation and improve health. More recently, Pycnogenol has been subjected to more than 100 research trials. In vitro and animal studies using the standardized extract have indicated a multimodal action of Pycnogenol, and several human studies have shown improvements in cognitive function after chronic administration. In this paper, we review these studies in the context of understanding both biological and cognitive changes due to Pycnogenol and evaluate possibilities of Pycnogenol to improve neurocognitive function.

Pycnogenol supplementation as an adjunct treatment for antidepressant-induced sexual dysfunction

INTRODUCTION

Major depressive disorder is a serious mental disorder in which treatment with antidepressant medication is associated with incidence of adverse events, such as constipation, diarrhea, dry mouth, headache, insomnia, and sexual dysfunction (SDys). Escitalopram (ESC), an effective and safe selective serotonin reuptake inhibitor with good tolerability, was used in this study. In this study, we investigated the prospective effect of Pycnogenol (PYC), an antioxidant, anti-inflammatory, and vasodilator agent, on ESC-induced SDys.

METHODS

This was a randomized, parallel, open-label study. Seventy-two outpatients of both genders with depression were randomized into two groups as follows: 37 patients from the ESC + PYC group took 50 mg of PYC per day for 4 months in ESC co-treatment, and 35 subjects from the ESC group took ESC only. Five patients dropped out and were excluded from the analysis. The participants were examined every month (visits 1-4).

RESULTS

ESC use led to improvement of depressive symptoms and severity scored by standardized psychiatric tests. PYC co-treatment resulted in attenuation of SDys beginning at 1 month of treatment and continuing for two consecutive months. Furthermore, an increase in heart rate in the PYC group was registered.

CONCLUSIONS

We propose that PYC-mediated SDys attenuation is based on its ability to improve endothelial functions by its antioxidant, anti-inflammatory, vasodilatory, and anticoagulant action. We assume that the action of PYC on heart rate is in accordance with the aforementioned vasodilatory action of PYC and consequent baroreflex-mediated heart rate response. PYC co-treatment reduced ESC-induced SDys and elevated heart rate.

Herbal Dietary Supplements for Erectile Dysfunction: A Systematic Review and Meta-Analysis

PURPOSE

Erectile dysfunction (ED) is a common condition that significantly affects quality of life and interpersonal relationships.

OBJECTIVE

Our objective was to perform a systematic review and meta-analysis to evaluate the efficacy of herbal dietary supplements in the treatment of ED.

MATERIALS AND METHODS

We searched five databases to identify randomized controlled trials (RCTs) that evaluated the clinical efficacy of herbal medicines in ED. Quality was assessed and risk of bias was estimated using the Jadad score and the Cochrane risk-of-bias tool.

RESULTS

In total, 24 RCTs, including 2080 patients with ED, were identified. Among these, 12 evaluated monopreparations (five ginseng [n = 399], three saffron [n = 397], two Tribulus terrestris [n = 202], and one each Pinus pinaster [n = 21] and Lepidium meyenii [n = 50]), seven evaluated formulations (n = 544), and five investigated dietary supplements in combination with pure compounds (n = 410). Ginseng significantly improved erectile function (International Index of Erectile Function [IIEF]-5 score: 140 ginseng, 96 placebo; standardized mean difference [SMD] 0.43; 95% confidence interval [CI] 0.15-0.70; P < 0.01; I² = 0), P. pinaster and L. meyenii showed very preliminary positive results, and saffron and T. terrestris treatment produced mixed results. Several herbal formulations were associated with a decrease of IIEF-5 or IIEF-15, although the results were preliminary. The quality of the included studies varied, with only seven having a prevalent low risk of bias. The median methodological quality Jadad score was three out of a maximum of five. Adverse events were recorded in 19 of 24 trials, with no significant differences between placebo and verum in placebo-controlled studies.

CONCLUSIONS

Encouraging evidence suggests that ginseng may be an effective herbal treatment for ED. However, further, larger, and high-quality studies are required before firm conclusions can be drawn. Promising (although very preliminary) results have also been generated for some herbal formulations. Overall, more research in the field, adhering to the CONSORT statement extension for reporting trials, is justified before the use of herbal products in ED can be recommended.

Pleiotropic Effects of French Maritime Pine Bark Extract to Promote Healthy Aging

Extension of the healthy life span is of primary importance for the aging society. Among exercise, healthy nutrition, and mental training, food supplements are widely used as preventive measures to postpone the diverse symptoms of aging. The extract from the bark of the French maritime pine, Pycnogenol, rich on flavonoids, has anti-inflammatory and antioxidative property, proven in in vivo studies. The extract reduces oxidative stress and improves endothelial health. Its antithrombotic properties are based on inhibition of platelet aggregation. In double-blind, placebo-controlled clinical studies, Pycnogenol shows diverse positive effects. With respect to cardiovascular symptoms, the extract has an antihypertensive effect, slows down the progression of atherosclerosis, and prevents venous thrombosis. As reported in studies in China and the United States, type 2 diabetes and diabetic retinopathy is improved with Pycnogenol. The extract restores mobility of seniors in case of patients suffering from osteoarthritis, Pycnogenol reduces pain and stiffness and use of analgesics. Furthermore, cognitive functions of elderly people, especially spatial memory, are significantly ameliorated. Climacteric symptoms are significantly alleviated by the pine bark extract. Urinary symptoms of benign prostatic hyperplasia are reduced by Pycnogenol. In combination with L-arginine, Pycnogenol restores erectile function in men with erectile dysfunction. The sum of these positive effects on relevant symptoms of aging suggests using Pycnogenol for a more extended period of healthy aging.

Sexual Activity in Patients with Cardiac Diseases

SUMMARY – In this article, we outline the latest guidelines published by the American Heart Association on sexual activity in patients with coronary artery disease, heart failure, structural heart diseases, arrhythmias, implanted pacemakers or cardioverter defibrillators, as well as on treatment options of sexual dysfunction. Sexual activities are similar to mild/moderate physical activity during a short period. Most patients are recommended to involve in sexual activity after prior comprehensive evaluation of physical condition. Those with stable cardiac symptoms and good functional capacity are at a low risk of adverse cardiovascular events, and others require treatment or stabilization before involving in sexual activity. Stress testing is useful in evaluating safety of sexual activity in patients with questionable or undetermined risk. Treatment of sexual dysfunction includes counseling of patients and their sexual partners, and drug treatment with phosphodiesterase inhibitors (sildenafil, tadalafil, vardenafil) which have been demonstrated to be safe and effective, in men, and with serotonin reuptake inhibitors (flibanserin) and local vaginal estrogen administration in women. In conclusion, in routine clinical practice, patients should be approached individually and multidisciplinarily in order to detect and eliminate the factors that interfere with normal sexual activities and disturb the quality of life.

Effects of a supplement combining Pycnogenol® and l-arginine aspartate on lower urinary dysfunction compared with saw palmetto extract

Objectives

Lower urinary tract symptoms (LUTS) and sexual dysfunction (SDys) are common problems that affect quality of life (QOL) in elderly men. In addition to prescribed drugs, many over-the-counter medications including supplements are used to treat QOL diseases. Phosphodiesterase inhibitors are reported to be effective for both LUTS and SDys by increasing nitric oxide levels. French maritime pine bark extract Pycnogenol^®, which is a potent nitric oxide donor, is reported to be effective for SDys. However, no reports have been published on whether it ameliorates LUTS.

Design

Open-labeled, randomized study. The effects of two supplements, Nokogiriyashi EX^® containing 160 mg saw palmetto (SP) extract per tablet and Edicare^® containing 10 mg of Pycnogenol^®, 115 mg of l-arginine and 92 mg of aspartate (PAA) per tablet on International Prostate Symptom Score (IPSS), IPSS–QOL, Overactive Bladder Symptom Score (OABSS), International Index of Erectile Function 5 (IIEF5), Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF), urinary 8-OHdG and uroflowmetry (UFM) of total 40 men with LUTS and SDys were examined.

Results

19 subjects were instructed to take two tablets of SP, on the other 20 were on four tablets of PAA for 16 weeks. IPSS and IPSS–QOL showed statistically significant improvements in both groups. OABSS and IIEF5 were significantly improved in the PAA group. Conversely, ICIQ-SF, 8-OHdG and UFM did not change in either group.

Conclusions

PAA might be an effective therapeutic alternative for elderly patients with LUTS and SDys.

A model for managing erectile dysfunction following prostate cancer treatment

PURPOSE OF REVIEW

Radical prostatectomy, regardless of the technology used intraoperatively, induces erectile dysfunction for most men who undergo the procedure. For many men, this proves to be transient. Penile rehabilitation strategies have been developed with the goal of increasing the probability and speed of return of sexual function. The purpose of this work is to review the fundamentals of erectile dysfunction relevant to the postprostatectomy patient as well as the components that are often included in penile rehabilitation strategies.

RECENT FINDINGS

Preservation of smooth muscle tissue is the key to preserving erectile function. This can be accomplished by providing the penis with regular exposure to oxygenated blood through intracaversonal injection therapy or vacuum erection device therapy. Dietary supplementation aimed to increase the nitric oxide production can also be beneficial. As well, chronic administration of PDE5 inhibitors may also help maintain the smooth muscle/collagen ratio in the corporal tissue.

SUMMARY

These findings have led to the development of our management model that includes daily vacuum erection device therapy, dietary supplementation and PDE5 inhibitors which is described in detail. The success of any rehabilitation strategy is dependent on the patient compliance which needs to be facilitated by care-giver encouragement and the setting of realistic expectations.

Effects of Korean ginseng berry extract on sexual function in men with erectile dysfunction: a multicenter, placebo-controlled, double-blind clinical study

Ginseng is beneficial for many aspects of human physiology, including sexual function. In this study, we have evaluated the efficacy and safety of an extract of ginseng berry, which has a ginsenoside profile distinct from other parts of the plant, on sexual function in men with erectile dysfunction. In all, 119 men with mild-to-moderate ED participated in a multicenter, randomized, double-blind, parallel, placebo-controlled clinical study. They were administered 4 tablets of either standardized Korean ginseng berry (SKGB, 350 mg ginseng berry extract per tablet), or placebo, daily, for 8 weeks. Efficacy was assessed with the International Index of Erectile Function (IIEF)-15 and premature ejaculation diagnostic tool (PEDT) at the end of the 4th and 8th week. We observed that the total and each of the individual domain scores of IIEF-15 increased from 40.95 ± 7.05 to 46.19 ± 12.69 significantly in the SKGB by the 8th week (P<0.05). The erectile function domain of IIEF changed slightly from 17.17 ± 2.57 to 18.59 ± 5.99 in the SKGB group by the 8th week (P<0.05). In addition, PEDT scores significantly improved from 9.14 ± 4.57 to 7.97 ± 4.4 and 7.53 ± 4.26 in the SKGB group after 4 and 8 weeks of treatment (P<0.05). Safety markers including hormone and lipid in the blood were assessed at the end of the 4th and 8th week and they remained unchanged. Oral administration of the SKGB extract improved all domains of sexual function. It can be used as an alternative medicine to improve sexual life in men with sexual dysfunction.