CXCL5 Cytokine Is a Major Factor in Platelet-Rich Plasma's Preservation of Erectile Function in Rats After Bilateral Cavernous Nerve Injury

Platelet-rich plasma (PRP) in nerve repair

Platelet-rich plasma (PRP) has the capability of assisting in the recovery of damaged tissues by releasing a variety of biologically active factors to initiate a hemostatic cascade reaction and promote the synthesis of new connective tissue and revascularization. It is now widely used for tissue engineering repair. In addition, PRP has demonstrated nerve repair and pain relief, and has been studied and applied to the facial nerve, median nerve, sciatic nerve, and central nerve. These suggest that PRP injection therapy has a positive effect on nerve repair. This indicates that PRP has high clinical value and potential application in nerve repair. It is worthwhile for scientists and medical workers to further explore and study PRP to expand its application in nerve repair, and to provide a more reliable scientific basis for the opening of a new approach to nerve repair.

Platelet-rich plasma for the treatment of erectile dysfunction: a systematic review of preclinical and clinical studies

INTRODUCTION

There has been tremendous growth in regenerative medicine during the last decade. For erectile dysfunction (ED), after the inclusion of low-intensity shockwave therapy as a treatment modality for ED management by the European Association of Urology sexual health guidelines, intracavernosal injection of platelet-rich plasma (PRP) has gained popularity between urologists and patients as a novel ED therapeutic modality with initial promising results. However, limited clinical data exist regarding efficacy and safety in patients with ED. Furthermore, despite numerous preclinical studies in other tissues and organs, the mechanism of action for restoring erectile function remains undetermined.

OBJECTIVES

This systematic review aims to present the current status of preclinical and clinical evidence regarding the use of PRP as treatment option for ED.

METHODS

A systematic literature search was conducted using PubMed, Cochrane, and ScienceDirect databases, until February 2023 for studies exploring the effect of PRP on ED.

RESULTS

We identified 517 articles, 23 of which were included in this review. These were 7 preclinical (of which 1 was a comparative trial and 6 were placebo-controlled randomized controlled trials) and 16 clinical studies (of which 1 was a comparative trial, 5 were randomized trials, and 2 were placebo-controlled randomized controlled trials). Preclinical data support the regenerative role of PRP in erectile tissue, in accordance with existing evidence in other tissues. Randomized clinical studies, as well as the first 2 available randomized, placebo-controlled clinical trials, showed promising efficacy and a lack of any adverse events.

CONCLUSION

As PRP for ED is widely used worldwide, there is an urgent need for high-quality studies with long-term follow-up. Standardization of research protocols, especially on the quality of PRP preparation, is also needed.

Effects of Platelet-Rich Plasma on the Oxymetholone-Induced Testicular Toxicity

Oxymetholone is one of the anabolic steroids that has widely been used among teenagers and athletes to increase their muscle bulk. It has undesirable effects on male health and fertility. In this study, the therapeutic effects of platelet-rich plasma (PRP) on oxymetholone-induced testicular toxicity were investigated in adult albino rats. During the experiments, 49 adult male albino rats were divided into 4 main groups: Group 0 (donor group) included 10 rats for the donation of PRP, Group I (control group) included 15 rats, Group II included 8 rats that received 10 mg/kg of oxymetholone orally, once daily, for 30 days, and Group III included 16 rats and was subdivided into 2 subgroups (IIIa and IIIb) that received oxymetholone the same as group II and then received PRP once and twice, respectively. Testicular tissues of all examined rats were obtained for processing and histological examination and sperm smears were stained and examined for sperm morphology. Oxymetholone-treated rats revealed wide spaces in between the tubules, vacuolated cytoplasm, and dark pyknotic nuclei of most cells, as well as deposition of homogenous acidophilic material between the tubules. Electron microscopic examination showed vacuolated cytoplasm of most cells, swollen mitochondria, and perinuclear dilatation. Concerning subgroup IIIa (PRP once), there was a partial improvement in the form of decreased vacuolations and regeneration of spermatogenic cells, as well as a reasonable improvement in sperm morphology. Regarding subgroup IIIb (PRP twice), histological sections revealed restoration of the normal testicular structure to a great extent, regeneration of the spermatogenic cells, and most sperms had normal morphology. Thus, it is recommended to use PRP to minimize structural changes in the testis of adult albino rats caused by oxymetholone.

Intracavernous injection of platelet-rich plasma reverses erectile dysfunction of chronic cavernous nerve degeneration through reduction of prostate hyperplasia evidence from an aging-induced erectile dysfunction rat model

Age-induced erectile dysfunction (ED) is a convoluted medical condition, and restoring erectile function (EF) under geriatric conditions is highly complicated. Platelet-rich plasma (PRP) treatment is an inexpensive cell-based therapeutic strategy. We have aimed to restore EF in aged-ED rats with PRP as a therapeutic tool. Male rats were grouped into aged and young according to age. The young rats were considered as normal control (NC) and treated with saline. Aged were further divided into 2 groups and treated with intracavernous (IC) PRP and saline. Treatment was scheduled at the 9th and 10th week for NC and 41th and 42th week for aged-ED rats, with EF analysis scheduled on the 12th week for NC and 44th week for aged-ED rats, respectively. Erectile response, immunofluorescence staining, and electron microscopic analyses were performed. IC PRP treatment effectively reduced prostate hyperplasia (PH). EF response indicated a significant increase in crucial EF parameters in PRP-treated aged-ED rats. Histological evidence denoted a rigid and restored development of tunica adventitia of the dorsal artery, decreased vacuolation of the dorsal penile nerve, and structural expansion of the epineurium. Masson's trichrome and immunostaining results affirmed an elevated expression of α-smooth muscle actin (α-SMA) in the corpus cavernosum (CC). Ultrastructure findings revealed that PRP effectively rejuvenated degenerating nerves, preserved endothelium and adherent junctions of corporal smooth muscle, and restored the axonal scaffolds by upregulating neurofilament-H (NF-H) expression. Finally, PRP enhanced neural stability by enhancing the axonal remyelination processes in aged-ED rats. Hence, PRP treatment was proven to restore EF in aged-ED rats, which was considered a safe, novel, cost-effective, and hassle-free strategy for EF restoration in geriatric patients.

Molecular pathogenesis and treatment of cavernous nerve injury-induced erectile dysfunction: A narrative review

Introduction: Erectile dysfunction (ED) is a common complication after radical prostatectomy (RP), and it seriously affects the quality of life in patients and their partners. The primary trigger of postoperative ED is surgical injury to the cavernous nerves that control penile erection and run along the anterolateral aspect of the prostate. Despite the introduction and ongoing innovation of nerve-sparing techniques, a significant number of patients still suffer from moderate cavernous nerve injury (CNI), which is thought to be transient and reversible. Therefore, early postoperative penile rehabilitation therapy may salvage patients’ erectile function by promoting cavernous nerve regeneration and preventing penile structural alterations.

Aims: To present a comprehensive overview of the current molecular pathogenesis of CNI-induced ED, as well as novel therapeutic strategies and their potential mechanisms.

Methods: A literature search was performed using PubMed. Search terms included erectile dysfunction, cavernous nerve injury, pathogenesis, pathway, and treatment.

Results: The NOS/NO pathway, oxidative stress-related pathway, RhoA/ROCK pathway, transforming growth factor-β (TGF-β), sonic hedgehog (Shh), and hydrogen sulfide (H2S) are involved in the molecular pathogenesis of CNI-induced ED. Multiple neurotrophins, including brain-derived nerve growth factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and neurturin (NTN), were found to promote cavernous nerve regeneration. Emerging therapeutic approaches can be roughly summarized into four categories, namely small molecule and drug, stem cell-based therapy (SCT), micro-energy therapy and platelet-rich plasma (PRP) therapy.

Conclusion: These pathways collectively lead to the irreversible damage to the penile structure after CNI. The combined early rehabilitation strategies of promoting upstream nerve regeneration and recovering abnormal molecular signals of downstream penis are presumed to save patients’ erectile function after RP. In future studies, the cross-talk between these molecular pathways needs to be further clarified, and the questions of how denervation injury induces the molecular alterations in the penis also need to be addressed.

Erectile dysfunction: Is platelet-rich plasma the new frontier for treatment in patients with erectile dysfunction? A review of the existing evidence

Erectile dysfunction (ED) is one of the commonest disorders in adult males and affects 12–19% of men of reproductive age. Only few studies have evaluated the impact of ED on men and couples with infertility—these studies report higher rates of ED in this sub-group of men compared to the general population, with the prevalence of ED in men diagnosed with male infertility ranging from 6.7 to 61.6%. Nevertheless, ED is considered a rare cause of male infertility, accounting for about 0.4–5% of all causes of male infertility. ED remains a poorly treated condition globally and current therapies, like oral medication, offer only temporary symptomatic relief and do not influence disease progression—patients are potentially on lifelong treatment, with ED worsening over time. In contrast, regenerative medicine may potentially reverse or halt the progression of ED processes. In this article, we review the evidence for intracavernosal injections of platelet-rich plasma (PRP) in the treatment of ED.

Assessment of the intracavernosal injection platelet-rich plasma in addition to daily oral tadalafil intake in diabetic patients with erectile dysfunction non-responding to on-demand oral PDE5 inhibitors

This study aimed to evaluate the effectiveness of ICI of platelet-rich plasma (PRP) in addition to daily oral tadalafil intake in diabetic erectile dysfunction (ED) patients non-responding to PDE5 inhibitors. Overall, 48 patients complaining of ED non-responding to on-demand PDE5 inhibitors were allocated into 2 equal groups, diabetics and non-diabetics that were given a daily dose of 5 mg tadalafil plus vardenafil 20 mg on demand during the study besides being subjected to 3 doses of ICI of PRP, 4 weeks apart. Responses to on-demand PDE5 inhibitors, International index of erectile function-5 (IIEF-5) score, erection hardness scores (EHS) and pharmaco-dynamic duplex studies were assessed. After PRP injections, 33% and 50% of cases were satisfied with on-demand PDE5 inhibitors, respectively, whereas 41% and 66% of them showed improved EHS response. Compared with baseline scores, the mean IIEF-5 scores were significantly improved after PRP therapy in the diabetic ED group (12.1 vs. 8.04, p = 0.003) as well as in the non-diabetic ED group (14.8 vs. 10.2, p = 0.001) linked to pharmaco-penile duplex readings. Both good and fair diabetic control exhibited significant responses to ICI therapy of PRP compared with bad controlled cases. The significant improvement included; the IIEF-5 score increase (86.7%, 126% vs. 16.1%), improved EHS as well as penile duplex readings. Baseline HbA1C demonstrated a significant negative correlation with IIEF-5 score before (p = 0.019) and after PRP therapy (p = 0.002) respectively. It could be concluded that ICI of PRP could be an effective therapy for treating ED patients non-responding to on-demand oral PDE5 treatment.

Evaluation of Platelet-Rich Plasma Therapy for Peripheral Nerve Regeneration: A Critical Review of Literature

Peripheral nerve injury (PNI) is a common disease in clinic, and the regeneration process of peripheral nerve tissue is slow, and patients with PNI often suffer from the loss of nerve function. At present, related research on the mechanism of peripheral nerve regeneration has become a hot spot, and scholars are also seeking a method that can accelerate the regeneration of peripheral nerve. Platelet-rich plasma (PRP) is a platelet concentrate extracted from autologous blood by centrifugation, which is a kind of bioactive substance. High concentration of platelets can release a variety of growth factors after activation, and can promote the proliferation and differentiation of tissue cells, which can accelerate the process of tissue regeneration. The application of PRP comes from the body, there is no immune rejection reaction, it can promote tissue regeneration with less cost, it is,therefore, widely used in various clinical fields. At present, there are relatively few studies on the application of PRP to peripheral nerve regeneration. This article summarizes the literature in recent years to illustrate the effect of PRP on peripheral nerve regeneration from mechanism to clinical application, and prospects for the application of PRP to peripheral nerve.