Sleep has attracted extensive attention due to its significance in health. However, its association with erectile dysfunction (ED) is insufficiently investigated. To investigate the potential causal links between sleep traits (insomnia, sleep duration, and chronotype) and ED, this study was performed. The single-nucleotide polymorphisms (SNPs) associated with insomnia, sleep duration, and chronotype were retrieved from previous genome-wide association studies (GWAS). A conventional two-sample Mendelian randomization (MR) was used to estimate the causal links between sleep traits and ED. The summary statistics of ED were from individuals of European ancestry (6175 cases vs 217 630 controls). As shown by the random effect inverse-variance-weighting (IVW) estimator, genetically predicted insomnia was causally associated with a 1.15-fold risk of ED (95% confidence interval: 1.07-1.23, P < 0.001). Sleep duration and morningness were not causally associated with ED, as indicated by the IVW (all P > 0.05). These findings were consistent with the results of sensitivity analyses. Based on genetic data, this study provides causal evidence that genetically predicted insomnia increases the risk of ED, whereas sleep duration and chronotype do not.
Male ; Humans ; Sleep Initiation and Maintenance Disorders/genetics* ; Genome-Wide Association Study ; Erectile Dysfunction/genetics* ; Sleep/genetics* ; Phenotype ; Polymorphism, Single Nucleotide

MicroRNAs (miRNAs) are short non-coding RNAs consisting of approximately 19－23 nucleotides and involved in many pathological and physiological processes by regulating post-transcriptional gene expressions. ED is one of the common male sexual dysfunctions seriously affecting the patient's quality of life, for which there is currently a lack of effective treatments clinically. More and more experiments have demonstrated that miRNAs are involved in the pathological process of different types of ED. This article presents an overview of the progress in the studies of the pathogenic role of miRNAs in ED.
Erectile Dysfunction/genetics* ; Gene Expression ; Humans ; Male ; MicroRNAs/genetics* ; Quality of Life

The aim of this study was to investigate the mechanism by which a diet inducing high hyperhomocysteinemia (HHcy) leads to the deterioration of erectile function in rats and whether this is inhibited by expression of the human tissue kallikrein-1 (hKLK1) gene. We established a rat model of HHcy by feeding methionine (Met)-rich diets to male Sprague-Dawley (SD) rats. Male wild-type SD rats (WTRs) and transgenic rats harboring the hKLK1 gene (TGRs) were fed a normal diet until 10 weeks of age. Then, 30 WTRs were randomly divided into three groups as follows: the control (n = 10) group, the low-dose (4% Met, n = 10) group, and the high-dose (7% Met, n = 10) group. Another 10 age-matched TGRs were fed the high-dose diet and designated as the TGR+7% Met group. After 30 days, in all four groups, erectile function was measured and penile tissues were harvested to determine oxidative stress, endothelial cell content, and penis fibrosis. Compared with the 7% Met group, the TGR+7% Met group showed diminished HHcy-induced erectile dysfunction (ED), indicating the improvement caused by hKLK1. Regarding corpus cavernosum endothelial cells, hKLK1 preserved endothelial cell-cell junctions and endothelial cell content, and activated protein kinase B/endothelial nitric oxide synthase (Akt/eNOS) signaling. Fibrosis assessment indicated that hKLK1 preserved normal penis structure by inhibiting apoptosis in the corpus cavernosum smooth muscle cells. Taken together, these findings showed that oxidative stress, impaired corpus cavernosum endothelial cells, and severe penis fibrosis were involved in the induction of ED by HHcy in rats, whereas hKLK1 preserved erectile function by inhibiting these pathophysiological changes.
Animals ; Apoptosis ; Diet ; Endothelial Cells ; Erectile Dysfunction/prevention & control* ; Fibrosis ; Humans ; Hyperhomocysteinemia/complications* ; Male ; Methionine ; Oxidative Stress ; Penis/pathology* ; Rats ; Rats, Sprague-Dawley ; Rats, Transgenic ; Signal Transduction/genetics* ; Tissue Kallikreins/genetics*

We evaluated whether LIM-kinase 2 inhibitor (LIMK2i) could improve erectile function by suppressing corporal fibrosis through the normalization of the Rho-associated coiled-coil protein kinase 1 (ROCK1)/LIMK2/Cofilin pathway in a rat model of cavernous nerve crush injury (CNCI). Sixty 11-week-old male Sprague-Dawley rats were divided equally into five groups: sham surgery (S), CNCI (I), and CNCI treated with low-dose (L), medium-dose (M), and high-dose (H) LIMK2i. The L, M, and H groups were treated with a daily intraperitoneal injection of LIMK2i (2.5, 5.0, and 10.0 mg kg^-1 body weight, respectively) for 1 week after surgery. The erectile response was assessed using electrostimulation at 1 week, postoperatively. Penile tissues were processed for Masson's trichrome staining, double immunofluorescence, and Western blot assay. Erectile responses in the H group improved compared with the I group, while the M group showed only partial improvement. A significantly decreased smooth muscle/collagen ratio and an increased content of fibroblasts positive for phospho-LIMK2 were noted in the I group. The M and H groups revealed significant improvements in histological alterations and the dysregulated LIMK2/Cofilin pathway, except for LIMK2 phosphorylation in the M group. The inhibition of LIMK2 did not affect the ROCK1 protein expression. The content of fibroblasts positive for phospho-LIMK2 in the H group returned to the level found in the S group, whereas it did not in the M group. However, the L group did not exhibit such improvements. Our data suggest that the inhibition of LIMK2, particularly with administration of 10.0 mg kg^-1 body weight LIMK2i, can improve corporal fibrosis and erectile function by normalizing the LIMK2/Cofilin pathway.
Animals ; Cofilin 1/metabolism* ; Electric Stimulation ; Erectile Dysfunction/etiology* ; Fibroblasts/pathology* ; Fibrosis/drug therapy* ; Lim Kinases/antagonists & inhibitors* ; Male ; Penile Diseases/drug therapy* ; Penis/innervation* ; Peripheral Nerve Injuries/pathology* ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Signal Transduction/drug effects* ; rho-Associated Kinases/genetics*

Men with diabetic erectile dysfunction (ED) respond poorly to the currently available oral phosphodiesterase-5 inhibitors. Therefore, functional therapies for diabetic ED are needed. Stromal vascular fraction (SVF) and the adenovirus-mediated cartilage oligomeric matrix angiopoietin-1 (Ad-COMP-Ang1) gene are known to play critical roles in penile erection. We previously reported that SVF and Ad-COMP-Ang1 have only a short-term effect in restoring erectile function. Further improvements to ED therapy are needed for long-lasting effects. In the present study, we aimed to test if the combination of SVF and Ad-COMP-Ang1 could extend the erection effect in diabetic ED. We found that the combination therapy showed a long-term effect in restoring erectile function through enhanced penile endothelial and neural cell regeneration. Combination therapy with SVF and Ad-COMP-Ang1 notably restored cavernous endothelial cell numbers, pericyte numbers, endothelial cell-cell junctions, decreased cavernous endothelial cell permeability, and promoted neural regeneration for at least 4 weeks in diabetic mice. In summary, this is an initial description of the long-term effect of combination therapy with SVF and Ad-COMP-Ang1 in restoring erectile function through a dual effect on endothelial and neural cell regeneration. Such combination therapy may have therapeutic potential for the treatment of diabetic ED.
Angiopoietin-1/genetics* ; Animals ; Diabetes Mellitus, Experimental/metabolism* ; Endothelium, Vascular/metabolism* ; Erectile Dysfunction/therapy* ; Genetic Therapy/methods* ; Intercellular Junctions/metabolism* ; Male ; Mesenchymal Stem Cell Transplantation ; Mice ; Penile Erection/physiology* ; Permeability

Erectile dysfunction (ED) is a disease associated with a variety of factors such as age, psychological factors, physical conditions, and lifestyle, and it severely affects the patients quality of life. In the past, some non-coding RNAs (ncRNAs) transcribed by genes but not translated into the protein were regarded as the "waste" in the process of gene expression. But in the recent years, ncRNAs have been found to play a crucial role in regulating gene expression and its products, which may affect penile erectile function. This review focuses on the recent progress in the studies of the relationship between ncRNAs and erectile dysfunction.
Erectile Dysfunction ; genetics ; Gene Expression ; Humans ; Male ; Quality of Life ; RNA, Untranslated ; physiology

Erectile dysfunction (ED), as a common male disease, seriously affects the patients' sexual life quality. Most ED patients benefit from phosphodiesterase type 5 (PDE5) inhibitors, but some refractory ED sufferers fail to respond to them. With the rapid development of molecular biology, the relevant molecular signaling pathways of penile erection and molecular pathogenesis of ED have been gradually clarified, and attempts have been made at a better management or a complete cure of ED with advanced molecular biological methods such as the gene therapy. This article presents an overview on the research progress in the molecular signaling pathways, molecular pathogenesis, and gene therapy of ED.
Biomedical Research ; Erectile Dysfunction ; genetics ; therapy ; Genetic Therapy ; Humans ; Male ; Penile Erection ; genetics ; Phosphodiesterase 5 Inhibitors ; therapeutic use ; Quality of Life ; Signal Transduction

OBJECTIVETo explore the effect of the calcitonin gene related peptide (CGRP) on the phenotypic transformation of corpus cavernosum smooth muscle cells (CCSM) in diabetic rats with erectile dysfunction (ED).

METHODSModels of diabetes and diabetic ED were established in male Sprague-Dawley rats by administration of streptozotocin, and CCSMs were primarily cultured and subjected to immunocytochemical assay. The cells were divided into a diabetic ED and a normal control group, and exposed to 0, 10, 60 and 100 nmol/L of CGRP for 24 hours. Then the relative expressions of calponin 1 (Cnn1) and osteopontin (OPN) mRNA were determined by real-time fluorescence quantitative RT-PCR (qRT-PCR).

RESULTSThe rate of SMalpha-actin positive cells in the CCSMs was (95.94 +/- 0.03) %. The expression of Cnn1 mRNA was significantly lower while that of OPN mRNA remarkably higher in the diabetic ED rats (4.41 +/- 0.29 and 5.28 +/- 0.32) than in the normal controls (10.35 +/- 0.62 and 1.32 +/- 0.24) (P < 0.01). Exposure to 100 nmol/L of CGRP significantly upregulated the expression of Cnn1 mRNA and downregulated that of OPN mRNA as compared with the unexposed rats (6.9 +/- 0.22 vs 4.41 +/- 0.29 and 3.26 +/- 0.31 vs 5.28 +/- 0.32, P < 0.01).

CONCLUSIONCGRP can transform the phenotype of CCSMs in diabetic ED rats from contractile to synthetic type.

Animals ; Calcitonin Gene-Related Peptide ; pharmacology ; Calcium-Binding Proteins ; metabolism ; Cells, Cultured ; Diabetes Mellitus, Experimental ; complications ; genetics ; metabolism ; Erectile Dysfunction ; etiology ; genetics ; metabolism ; Male ; Microfilament Proteins ; metabolism ; Muscle, Smooth ; cytology ; metabolism ; Osteopontin ; metabolism ; Penis ; cytology ; drug effects ; metabolism ; Phenotype ; Rats ; Rats, Sprague-Dawley

Growth factors have a universal bioactivity. Gene therapy is a new strategy in dealing with erectile dysfunction (ED). This paper presents an overview on the value of growth factors, particularly the vascular epithelial growth factor (VEGF) and insulin-like growth factor 1 (IGF-1), in the treatment of ED.
Animals ; Erectile Dysfunction ; therapy ; Genetic Therapy ; Humans ; Insulin-Like Growth Factor I ; genetics ; Male ; Rats ; Vascular Endothelial Growth Factor A ; genetics

OBJECTIVETo investigate the changes of gene expression profiles associated with erectile dysfunction in diabetic rats.

METHODSAffymetrix Gene Chip arrays from the Gene Expression Omnibus (GEO) were used to examine the alterations in the gene expression profiles between streptozotocin-induced diabetic rats and littermate controls, and the data were analyzed with GeneSifter microarray analysis software.

RESULTSA total of 661 differentially expressed genes were identified, including 280 up-regulated and 381 down-regulated ones. Among the differentially expressed genes, kruppel-like factor 5 (klf5) was upregulated by 4.01 folds and ceruloplasmin(cp) by 5.14 folds; collagen, type XI, alpha1 was down-regulated by 5.84 folds and collagen, type I, alpha1 by 5.77 folds. The 661 differentially expressed genes involved such functional processes as glycoprotein biosynthesis, collagen fibril organization, angiogenesis in wound healing, triglyceride metabolism, cell proliferation and other important biological processes, and some pathways also involved such as fatty acid metabolism, neurodegenerative disorders, and ECM-receptor interactions.

CONCLUSIONSome genes such as klf5, cp, and collagen play important roles in the pathophysiology of diabetes-induced erectile dysfunction. Bioinformatic approaches offer a new means for identifying candidate genes and pathways relevant to the pathophysiology of diabetes-induced erectile dysfunction, highlighting also the potential complexity of this disorder.

Animals ; Computational Biology ; Diabetes Mellitus, Experimental ; complications ; genetics ; Erectile Dysfunction ; etiology ; genetics ; Gene Expression ; Gene Expression Profiling ; Male ; Oligonucleotide Array Sequence Analysis ; Rats