In most types of erectile dysfunction, particularly in advanced stages, typical pathological features observed are reduced parenchymal cells coupled with increased tissue fibrosis. However, the current treatment methods have shown limited success in reversing these pathologic changes. Recent research has revealed that changes in autophagy levels, along with alterations in apoptosis and fibrosis-related proteins, are linked to the progression of erectile dysfunction, suggesting a significant association. Autophagy, known to significantly affect cell fate and tissue fibrosis, is currently being explored as a potential treatment modality for erectile dysfunction. However, these present studies are still in their nascent stage, and there are limited experimental data available. This review analyzes erectile dysfunction from a pathological perspective. It provides an in-depth overview of how autophagy is involved in the apoptotic processes of smooth muscle and endothelial cells and its role in the fibrotic processes occurring in the cavernosum. This study aimed to develop a theoretical framework for the potential effectiveness of autophagy in preventing and treating erectile dysfunction, thus encouraging further investigation among researchers in this area.
Male ; Humans ; Autophagy/physiology* ; Apoptosis/physiology* ; Erectile Dysfunction/physiopathology* ; Fibrosis ; Penis/pathology* ; Animals ; Endothelial Cells/pathology* ; Myocytes, Smooth Muscle/pathology*

Pericytes are multifunctional mural cells that surround the abluminal wall of endothelial cells and are associated with vascular development, vascular permeability, and angiogenesis. Additionally, pericytes demonstrate stem cell-like properties and contribute to neuroinflammatory processes. Pericytes have been extensively studied in the central nervous system. However, specific mechanisms underlying its involvement in various physiological and pathological conditions, especially in erectile dysfunction (ED), remain poorly understood. Advancements in in vitro and in vitro techniques, such as single-cell RNA sequencing, are expanding our understanding of pericytes. Recent studies have shown that pericyte dysfunction is considered an important factor in the pathogenesis of vascular and neurological ED. Therefore, this study aims to analyze the specific role of pericytes in ED, focusing on diabetic and neurogenic ED. This article provides a comprehensive review of research findings on PubMed from 2000 to 2023, concerning pericyte dysfunction in the process of ED, offering valuable insights, and suggesting directions for further research.
Pericytes/physiology* ; Humans ; Male ; Penis/innervation* ; Erectile Dysfunction/physiopathology* ; Nerve Regeneration/physiology* ; Neovascularization, Physiologic/physiology* ; Animals ; Angiogenesis

Platelet-rich plasma (PRP) shows promise as a regenerative modality for mild-to-moderate erectile dysfunction (ED). However, its efficacy in treating severe ED remains unknown. Blood samples from 8-week-old male rats were used to prepare PRP through a two-step centrifugation procedure, followed by chitosan activation and freeze thaw cycle. A hyperhomocysteinemia (HHcy)-related ED model was established using a methionine-enriched diet, and an apomorphine (APO) test was conducted during the 4 th week. APO-negative rats were divided into two groups and were injected with PRP or saline every 2 weeks. Erectile function and histological analyses of the corpus cavernosum were performed during the 16 th week. The results revealed that erectile function was significantly impaired in rats with HHcy-related ED compared to that in age-matched rats but was improved by repeated PRP injections. Immunofluorescence staining revealed a reduction in reactive oxygen species and additional benefits on the recovery of structures within the corpus cavernosum in rats that received PRP treatment compared to those in the saline-injected control group. Therefore, PRP could enhance functional and structural recovery in a severe HHcy-related ED model. A notable strength of the present study lies in the use of a repeated intracavernous injection method, mirroring protocols used in human studies, which offers more reliable results for translating the findings to humans.
Animals ; Male ; Platelet-Rich Plasma ; Hyperhomocysteinemia/complications* ; Erectile Dysfunction/etiology* ; Rats ; Disease Models, Animal ; Penis ; Rats, Sprague-Dawley ; Reactive Oxygen Species/metabolism* ; Penile Erection/physiology* ; Apomorphine/administration & dosage*

We wanted to determine whether shear wave elastography (SWE) could be used to evaluate the aging degree of the corpus cavernosum (CC) and to identify the histological basis of changes in SWE measurements during the aging process. We performed a cross-sectional study enrolling healthy participants of different ages. We measured the Young's modulus (YM) of the penile CCs by SWE and assessed erectile function using the International Index of Erectile Function-5 (IIEF-5). Histological investigation was performed in surgically resected penile specimens from a separate group of patients to examine the smooth muscle and collagen content of the CCs. Furthermore, we measured the YM, erectile function, smooth muscle, and collagen content of the CCs in different age groups of rats. Finally, we enrolled 210 male volunteers in this study. The YM of the CC (CCYM) was positively correlated with age (r = 0.949, P < 0.01) and negatively correlated with erectile function (r = -0.843, P < 0.01). Histological examinations showed that CCs had increased collagen content but decreased smooth muscle content with increased age. The same positive correlation between CCYM and age was also observed in the animal study. In addition, the animal study showed that older rats, with increased CCYM and decreased erectile function, had lower smooth muscle content and higher collagen content. SWE can noninvasively and quantitatively evaluate the aging degree of the CC. Increased collagen content and decreased smooth muscle content might be the histological basis for the effect of aging on the CC and the increase in its YM.
Humans ; Male ; Rats ; Animals ; Erectile Dysfunction ; Elasticity Imaging Techniques ; Cross-Sectional Studies ; Penis/pathology* ; Penile Erection/physiology* ; Aging ; Collagen

Animals ; Brain ; embryology ; Ear ; embryology ; Esophagus ; embryology ; Fallopian Tubes ; embryology ; Female ; Heart ; embryology ; Humans ; Kidney ; embryology ; Liver ; embryology ; Lung ; embryology ; Male ; Organogenesis ; physiology ; Penis ; embryology ; Rabbits ; Stomach ; embryology ; Vagina ; embryology

Structural alterations in fibroelastic components of the penile corpus cavernousum (CC) may impair its compliance, resulting in venous leakage and erectile dysfunction (ED). Our study evaluated the effectiveness of noninvasive two-dimensional shear-wave elastography (2-D SWE) in quantifying penile CC lesions in rabbits with hyperlipidemia-induced ED. A total of 12 New Zealand white rabbits were randomly divided into two groups. Six were fed a high-cholesterol diet containing 2% cholesterol and 8.5% lard for 10 weeks and the other six were fed normal diet as controls. We measured the shear-wave elastic quantitative (SWQ) value of penile CC by 2-D SWE. Erectile function was investigated by intracavernous injection of papaverine, and immunohistochemical (IHC) staining and the western blot analysis to determine the penile CC lesions. After 10 weeks, the SWQ values obtained from penile CC were remarkably higher in the high-cholesterol-fed compared with the control group, and the ΔICP (ICP plateau minus ICP baseline)/MAP (ICP: intracavernous pressure, MAP: mean arterial pressure) was markedly decreased. The IHC staining and western blot revealed extracellular matrix (ECM) accumulation in penile cavernous tissues, and the smooth muscle cell (SMC) phenotypic transition was affected, as indicated by reduced alpha-smooth muscle actin and calponin-1 expression and increased phospho-myosin light chain₂₀ (p-MLC₂₀)/MLC₂₀ and osteopontin expression. Hyperlipidemia resulted in ECM accumulation accompanied with SMC phenotypic transition in penile CC and impaired the erectile function eventually. These might, in turn, lead to variations in the SWQ values. It suggests that 2-D SWE may be a novel, noninvasive and effective approach that distinguishes penile CC lesions secondary to hyperlipidemia from normal.
Animals ; Disease Models, Animal ; Elasticity Imaging Techniques/methods* ; Erectile Dysfunction/etiology* ; Hyperlipidemias/diagnostic imaging* ; Male ; Penile Erection/physiology* ; Penis/diagnostic imaging* ; Rabbits

ObjectiveTo investigate the protective effect of human urine-derived stem cells (USCs) on erectile function and cavernous structure in rats with cavernous nerve injury (CNI).

METHODSSixty adult male SD rats with normal sexual function were randomly divided into four groups of equal number: sham operation, bilateral CNI (BCNI) model control, phosphate buffered saline (PBS), and USC. The BCNI model was established in the latter three groups of rats by clamping the bilateral cavernous nerves. After modeling, the rats in the PBS and USC groups were treated by intracavernous injection of PBS at 200 μl and USCs at 1×106/200 μl PBS respectively for 28 days. Then, the maximum intracavernous pressure (mICP) and the ratio of mICP to mean arterial pressure (mICP/MAP) of the rats were calculated by electrical stimulation of the major pelvic ganglions, the proportion of nNOS- or NF200-positive nerve fibers in the total area of penile dorsal nerves determined by immunohistochemical staining, the levels of endothelial cell marker eNOS, smooth muscle marker α-SMA and collagen I detected by Western blot, and the smooth muscle to collagen ratio and the cell apoptosis rate in the corpus cavernosum measured by Masson staining and TUNEL, respectively.

RESULTSAfter 28 days of treatment, the rats in the USC group, as compared with those in the PBS and BCNI model control groups, showed significant increases in the mICP (［81 ± 9.9］ vs ［31 ± 8.3］ and ［33 ± 4.2］ mmHg, P <0.05), mICP/MAP ratio (0.72 ± 0.05 vs 0.36 ± 0.03 and 0.35 ± 0.04, P <0.05), the proportions of nNOS-positive nerve fibers (［11.31 ± 4.22］% vs ［6.86 ± 3.08］% and ［7.29 ± 4.84］% , P <0.05) and NF200-positive nerve fibers in the total area of penile dorsal nerves (［27.31 ± 3.12］% vs ［17.38 ± 2.87］% and ［19.49 ± 4.92］%, P <0.05), the eNOS/GAPDH ratio (0.52 ± 0.08 vs 0.31 ± 0.06 and 0.33 ± 0.07, P <0.05), and the α-SMA/GAPDH ratio (1.01 ± 0.09 vs 0.36 ± 0.05 and 0.38 ± 0.04, P <0.05), but a remarkable decrease in the collagen I/GAPDH ratio (0.28 ± 0.06 vs 0.68 ± 0.04 and 0.70 ± 0.10, P <0.05). The ratio of smooth muscle to collagen in the corpus cavernosum was significantly higher in the USC than in the PBS and BCNI model control groups (17.91 ± 2.86 vs 7.70 ± 3.12 and 8.21 ± 3.83, P <0.05) while the rate of cell apoptosis markedly lower in the former than in the latter two (3.31 ± 0.83 vs 9.82 ± 0.76, P <0.01; 3.31 ± 0.83 vs 9.75 ± 0.91, P <0.05).

CONCLUSIONSIntracavernous injection of USCs can protect the erectile function of the rat with cavernous nerve injury by protecting the nerves, improving the endothelial function, alleviating fibrosis and inhibiting cell apoptosis in the cavernous tissue.

Actins ; analysis ; Animals ; Arterial Pressure ; Collagen ; analysis ; Disease Models, Animal ; Erectile Dysfunction ; prevention & control ; Male ; Nitric Oxide Synthase Type I ; analysis ; Nitric Oxide Synthase Type III ; analysis ; Penile Erection ; physiology ; Penis ; innervation ; Pudendal Nerve ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Saline Solution ; administration & dosage ; Stem Cell Transplantation ; methods ; Stem Cells ; Urine ; cytology

Penile hypersensitivity plays an important role in premature ejaculation (PE), but differences in penile sensitivity among subtypes of PE are unknown. Therefore, we compared penile sensory thresholds in PE subtypes of lifelong and acquired PE, PE with and without erectile dysfunction (ED), PE with an intravaginal ejaculation latency time ≤1 min and >1 min, and PE with and without orgasmic pleasure perceptual dysfunction. During August 2014 to January 2016, 136 patients with PE were included. Penile warm, cold, and vibratory thresholds were measured. Data of clinical characteristics, sexual life, Premature Ejaculation Diagnostic Tool (PEDT) score, and the 5-item version of the International Index of Erectile Function (IIEF-5) score were collected. Vibratory thresholds of the PE with ED group were higher in the right coronal sulcus (median amplitude: 4.92 vs 3.65 μ m, P = 0.02) and the right penile shaft (median amplitude: 3.87 vs 3.30 μ m, P = 0.03), while differences in penile sensory thresholds between other subtypes were not significant. The median PEDT score was lower in the PE without ED group (12 vs 14, P < 0.001). The IIEF-5 and PEDT scores were negatively correlated (r = -0.29, P < 0.001). Patients with orgasmic pleasure perceptual dysfunction had a lower median IIEF-5 score (20 vs 21, P = 0.02). Patients with PE and ED had lower penile sensitivity, and ED was associated with more severe symptoms and weaker orgasmic pleasure perception. In men with PE, management of comorbid ED is necessary. In case of side effects in erectile function, topical anesthetics should be cautiously used in men with PE and ED.
Adolescent ; Adult ; Ejaculation ; Erectile Dysfunction/physiopathology* ; Humans ; Male ; Middle Aged ; Orgasm ; Penis/physiology* ; Physical Stimulation ; Pleasure ; Premature Ejaculation/physiopathology* ; Prospective Studies ; Sensory Thresholds ; Sexual Dysfunctions, Psychological ; Sexuality ; Surveys and Questionnaires ; Temperature ; Vibration ; Young Adult

Erectile dysfunction (ED) associated with type 2 diabetes is a severe problem that requires effective treatment. Pancreatic kininogenase (PK) has the potential to improve the erectile function of ED patients. This study aims to investigate the effect of PK on erectile function in streptozotocin-induced type 2 diabetic ED rats. To achieve this goal, we divided male Sprague-Dawley rats into five groups. One group was not treated, and the other four groups were treated with saline, sildenafil, PK or sildenafil, and PK, respectively, for 4 weeks after the induction of type 2 diabetic ED. Then, intracavernous pressure under cavernous nerve stimulation was measured, and penile tissue was collected for further study. Endothelial nitric oxide synthase levels, smooth muscle content, endothelium content, cyclic guanosine monophosphate (cGMP) levels in the corpus cavernosum, and neuronal nitric oxide synthase levels in the dorsal penile nerve were measured. Improved erectile function and endothelium and smooth muscle content in the corpus cavernosum were observed in diabetic ED rats. When treating diabetic ED rats with PK and sildenafil at the same time, a better therapeutic effect was achieved. These data demonstrate that intraperitoneal injection of PK can improve erectile function in a rat model of type 2 diabetic ED. With further research on specific mechanisms of erectile function improvement, PK may become a novel treatment for diabetic ED.
Animals ; Cyclic GMP/metabolism* ; Diabetes Mellitus, Experimental/physiopathology* ; Erectile Dysfunction/physiopathology* ; Kallikreins/therapeutic use* ; Male ; Muscle, Smooth, Vascular/physiopathology* ; Nitric Oxide Synthase Type I/metabolism* ; Nitric Oxide Synthase Type III/metabolism* ; Penile Erection/physiology* ; Penis/metabolism* ; Rats ; Rats, Sprague-Dawley ; Sildenafil Citrate/therapeutic use* ; Treatment Outcome ; Urological Agents/therapeutic use*

Objective: To search for the methods of isolating, purifying and culturing corpus cavernosal endothelial cells (CCECs) from SD rats, observe their growth characteristics, and providing seed cells for the study of erectile dysfunction (ED). METHODS: The corpus cavernosal tissue from the SD rat was digested with 0.1% elastase, followed by purification of CCECs with immunomagnetic beads. After further amplification, monoclonal CCECs were sorted out with the cloning cylinder and their morphological and proliferative characteristics were observed. The von Willebrand factor (VWF) in the CCECs was identified by immunofluorescence staining, the CD31 molecule detected by immumohistochemistry, the purity of the CCECs determined by flow cytometry, and the proliferation of the cells measured with CCK-8 and growth curves. RESULTS: After 7 days of purification and culture, the CCECs were fused into a monolayer under the inverted phase-contrast microscope, arranged like flagstones. The growth curves showed that the CCECs were in latency with a low growth rate at 1－2 days, in the logarithmic growth phase with a rapid rate at 3－4 days, and into the platform phase around the 6th day. VWF was positively expressed in the CCECs with much green fluorescence, and so was CD31 with a large number of brownish particles. The positive rate of the CCECs which were labelled with the VWF purified with magnetic beads combined with cloning cylinders was up to (91.9±3.75)%. CONCLUSIONS High-purity rat CCECs can be cultured successfully using immunomagnetic beads combined with cloning cylinders, with stable proliferation and passage in the endothelial cell medium.
Animals ; Cell Culture Techniques ; Cell Movement ; Cell Proliferation ; Cells, Cultured ; Endothelial Cells ; chemistry ; cytology ; physiology ; Erectile Dysfunction ; pathology ; Flow Cytometry ; Humans ; Immunomagnetic Separation ; Male ; Penis ; cytology ; Platelet Endothelial Cell Adhesion Molecule-1 ; analysis ; Rats ; Rats, Sprague-Dawley ; Sincalide ; analysis ; von Willebrand Factor ; analysis