Metabolic syndrome in rats is associated with erectile dysfunction by impairing PI3K/Akt/eNOS activity

ROUX-en-Y gastric bypass surgery improves metabolic syndrome-related erectile dysfunction in mice via the IRS-1/PI3K/AKT/eNOS pathway

Objective

Although many clinical studies have shown that ROUX-en-Y gastric bypass (RYGB) surgery significantly improves metabolic syndrome-related erectile dysfunction (MED), the role and mechanism are unclear.

Aim

In this study we used a mouse model to explore how RYGB improves MED induced by a high-fat diet (HFD).

Methods

We established a mouse model of metabolic syndrome by feeding an HFD for 16 weeks. The mice were randomly assigned to the standard chow diet (SCD), HFD, or RYGB groups. Body weight, fasting blood glucose, plasma insulin, and total plasma cholesterol were analyzed. Erectile responses were evaluated by determining the mean systolic blood pressure and the intracavernosal pressure (ICP). Penile histologic examination (Masson's trichrome and immunohistochemical stain) and Western blot were performed.

Result

Compared with the SCD group, the ICP in the sham group was significantly lower, and the ICP of the RYGB was significantly increased. Masson's trichrome and immunohistochemical staining showed that the content of endothelium and smooth muscle in the corpus cavernosum of mice with MED was significantly reduced. Western blot analysis showed a significant decrease in α-smooth muscle actin and a significant increase in osteopontin in penile tissue in the sham group, which was improved by RYGB surgery. Furthermore, RYGB significantly increased IRS-1/PI3K/Akt/eNOS phosphorylation.

Clinical Translation

In this study we explored the mechanism of bariatric surgery to improve erectile dysfunction associated with metabolic syndrome and provided a theoretical basis for clinical research.

Strengths and Limitations

First, we did not investigate the mechanism by which RYGB affects the IRS-1/PI3K/Akt/eNOS signaling pathway. Second, the effect of the IRS-1/PI3K/Akt/eNOS signaling pathway on the function of corpus cavernosum endothelial cells and smooth muscle cells remains to be investigated in cellular studies.

Conclusion

This study demonstrated that RYGB may not only improve metabolic parameters but also restore erectile function in MED patients. The mechanism of the therapeutic effect of RYGB may be reactivation of the IRS-1/PI3K/Akt/eNOS pathway.

Combining transcriptomic analysis and network pharmacology to explore the mechanism by which Shaofu Zhuyu decoction improves diabetes mellitus erectile dysfunction

BACKGROUND

Erectile dysfunction is common among the complications of diabetes mellitus. Shaofu Zhuyu decoction (SFZYD) is commonly used to treat diabetic mellitus erectile dysfunction (DMED). However, its main active components and specific mechanism are still unknown.

PURPOSE

To confirm the activity of SFZYD in improving DMED, explore the main active components of SFZYD, and clarify the underlying mechanism.

METHODS

A diabetic rat model was induced with streptozotocin (STZ). After intragastric administration, erectile function was assessed by the maximum intracavernous pressure (ICPmax)/mean arterial pressure (MAP). Corpus cavernosum fibrosis was evaluated by Masson staining, and ELISA methods were used to determine the serum levels of IL-6, TNF-α, IL-10, IL-4 and IL-1β to evaluate inflammation. Then, the main active components of SFZYD were identified by UPLC‒MS/MS. Finally, the target and biological mechanism of SFZYD in improving DMED were predicted by combined network pharmacology and transcriptomics, which was also validated by molecular docking and cellular thermal shift assay (CETSA) experiments.

RESULTS

SFZYD significantly improved erectile dysfunction and inhibited inflammatory responses and local tissue fibrosis in diabetic rats. A total of 1846 active components were identified by UPLC‒MS/MS, and isorhamnetin was the main active component. The transcriptomic results were used to identify differentially expressed genes among the control, DM and SFZYD groups, and 1264 differentially expressed genes were obtained from the intersection. The network pharmacology results showed that SFZYD acts on core targets such as AKT1, ALB, HSP90AA1 and ESR1 through core components such as isorhamnetin, quercetin and chrysophanic acid. Further combined analysis revealed that multiple targets, such as CYP1B1, DPP4, NOS2 and LCN2, as well as the regulation of the PI3K-AKT signaling pathway, may be important mechanisms by which SFZYD improves DMED. Molecular docking verification showed that isorhamnetin, the key component of SFZYD, has good binding ability with several core targets, and its binding ability with CYP1B1 was the strongest. The CETSA results showed that isorhamnetin binds to CYP1B1 in CCECs.

CONCLUSION

SFZYD improves DMED, inhibits the inflammatory response and alleviates local tissue fibrosis. The combined application of transcriptomic, network pharmacology, molecular docking and CETSA approaches was helpful for revealing the mechanism by which SFZYD improves DMED, which may be related to the regulation of CYP1B1 and the PI3K-Akt signaling pathway.

Identifying potential cross-talk signatures for the occurrence of atherosclerosis in diabetic erectile dysfunction

BACKGROUND

Erectile dysfunction and atherosclerosis are common cardiovascular complications in diseases. Clinical associations between erectile dysfunction and atherosclerosis have been noticed, but the specific mechanisms are not illustrated adequately.

OBJECTIVES

The aim of the study was to further mine associated pathological mechanisms and genetic alterations of atherosclerosis in diabetes mellitus-related erectile dysfunction.

MATERIALS AND METHODS

Significant atherosclerosis-related genes were identified from transcriptome data of diabetes mellitus-related erectile dysfunction and atherosclerosis-related gene sets from DisGeNET and GeneCard databases. Functional enrichment and immune infiltration analyses were performed to clarify the biological roles and pathways as well as immune responses of significant atherosclerosis-related gene sets. A protein-protein interaction network was constructed, and gene clusters were performed. Then, data of diabetic plaques and high-glucose cavernosum endothelial cells were analyzed for validation. And hub atherosclerosis-related gene sets were identified. Finally, expressed pattern of hub atherosclerosis-related gene sets were explored by single-cell profiling and immune analysis.

RESULTS

In total, 202 significant atherosclerosis-related gene sets including 100 upregulated and 102 downregulated genes were identified. These genes were related to endothelial cell migration, inflammatory response, regulation of oxidative stress, and immune response. In immune infiltration, immature dendritic cells and monocytes showed differential expression between the diabetes mellitus-related erectile dysfunction and control groups, A protein-protein interaction network containing 135 nodes was constructed. A hub atherosclerosis-related gene set signature consisting of HBEGF, LOX, NQO1, and VLDLR was obtained by multi-omics validation. In addition, Functional enrichment analysis revealed that hub atherosclerosis-related gene sets were involved in oxidoreductase activity and extracellular matrix organization.

DISCUSSION AND CONCLUSION

We explored atherosclerosis-related genetic changes and signaling pathways in diabetes mellitus-related erectile dysfunction. HBEGF, LOX, NQO1, and VLDLR were identified as hub atherosclerosis-related gene sets. These may serve as potential biomarkers for the clinical management of atherosclerosis and preventing further cardiovascular risks in diabetes mellitus-related erectile dysfunction.

Relaxin-2 Prevents Erectile Dysfunction by Cavernous Nerve, Endothelial and Histopathological Protection Effects in Rats with Bilateral Cavernous Nerve Injury

PURPOSE

Cavernous nerve injury induced erectile dysfunction (ED) is a refractory complication with high incidence in person under radical prostatectomy. Studies have shown that relaxin-2 (RLX-2) plays a vital role of endothelial protection, vasodilation, anti-fibrosis and neuroprotection in a variety of diseases. However, whether penile cavernous erection can benefit from RLX-2 remains unknown. The purpose of the experiment was to explore the effects of RLX-2 on ED in the rat suffering with bilateral cavernous nerve injury (BCNI).

MATERIALS AND METHODS

The rats were divided into three groups: Sham group was underwent sham operation, BCNI+RLX group or BCNI group was underwent bilateral cavernous nerve crush and then randomly treated with RLX-2 (0.4 mg/kg/d) or saline by continuous administration using a subcutaneously implanted micro pump for 4 weeks respectively. Then, erectile function was evaluated by electrical stimulation of cavernous nerves. Cavernous nerves and penile tissues and were collected for histological evaluation.

RESULTS

Erectile function of rats with BCNI was partially improved after RLX-2 treatment. The BCNI group had lower expression of relaxin family peptide receptor (RXFP) 1, p-AKT/AKT, p-eNOS/eNOS ratios than sham operation rats, but RLX-2 could partially reversed these changes. Histologically, the BCNI+RLX group had a significant effect on preservation of neurofilament, neuronal glial antigen 2 of penile tissue and nNOS of cavernous nerves when compared with BCNI group. RLX-2 could inhibited the lever of BCNI induced corporal fibrosis and apoptosis via regulating TGFβ1-Smad2/3-CTGF pathway and the expression of Bax/Bcl-2 ratio, caspase3.

CONCLUSIONS

RLX-2 could improve erectile function of BCNI rats by protecting cavernous nerve and endothelial function and suppressing corporal fibrosis and apoptosis via RXFP1 and AKT/eNOS pathway. Our findings may provide a promising treatment for refractory BCNI induced ED.

Uncovering the genetic links of diabetic erectile dysfunction and chronic prostatitis/chronic pelvic pain syndrome

Background: Clinical associations between erectile dysfunction and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) have been noticed, but the common pathogenic mechanisms between them remain elusive. The aim of the study was to mine shared genetic alterations between ED and chronic prostatitis/chronic pelvic pain syndrome. Method: Transcriptome data of ED and chronic prostatitis/chronic pelvic pain syndrome-related genes (CPRGs) were retrieved from relevant databases and differentially expressed analysis was used to obtain significant CPRGs. Then function enrichment and interaction analyses were performed to show shared transcriptional signature, including gene ontology and pathway enrichment, the construction of protein-protein interaction (PPI) network, cluster analysis, and co-expression analysis. Hub CPRGs and key cross-link were selected by validating these genes in clinical samples, chronic prostatitis/chronic pelvic pain syndrome and ED-related datasets. Then the miRNA-OSRGs co-regulatory network was predicted and validated. Subpopulation distribution and disease association of hub CPRGs were further identified. Result: Differentially expressed analysis revealed 363 significant CPRGs between ED and chronic prostatitis/chronic pelvic pain syndrome, functioning in inflammatory reaction, oxidative stress, apoptosis, smooth muscle cell proliferation, and extracellular matrix organization. A PPI network containing 245 nodes and 504 interactions was constructed. Module analysis depicted that multicellular organismal process and immune metabolic process were enriched. 17 genes were screened in PPI via topological algorithms, and reactive oxygen species as well as interleukin-1 metabolism were regarded as the bridging interactive mechanism. After screening and validation, a hub-CPRG signature consisting of COL1A1, MAPK6, LPL, NFE2L2 and NQO1 were identified and associated miRNA were verified. These miRNAs played an important role in immune and inflammatory response likewise. Finally, NQO1 was identified as a key genetic link between ED and chronic prostatitis/chronic pelvic pain syndrome. It was predominately enriched in corpus cavernosum endothelial cell, and correlated with other male urogenital and immune system diseases tightly. Conclusion: We identified the genetic profiles as well as corresponding regulatory network underlying interaction between ED and chronic prostatitis/chronic pelvic pain syndrome via multi-omics analysis. These findings expanded a new understanding for the molecular mechanism of ED with chronic prostatitis/chronic pelvic pain syndrome.

Ganoderma lucidum polysaccharide ameliorated diabetes mellitus-induced erectile dysfunction in rats by regulating fibrosis and the NOS/ERK/JNK pathway

Background

Diabetes mellitus-induced erectile dysfunction (DMED) is a frequent complication of diabetes mellitus (DM), with limited therapy at present. This study aimed to explore the role and mechanism of Ganoderma lucidum polysaccharide (GLP) on DMED.

Methods

DMED was induced in the experimental rats [male 12-week-old Sprague-Dawley (SD) rats] by treatment with streptozotocin (60 mg/kg) and apomorphine (APO). Next, rats in the GLP low dose (GLP-L)/GLP high dose (GLP-H) groups were treated with GLP (100 or 400 mg/kg/d, respectively) for 8 weeks. Subsequently, erectile function was assessed by APO and electrostimulation of the cavernous nerve (CN). Serum or penile testosterone (T), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and cyclic guanosine monophosphate (cGMP) contents were evaluated by enzyme-linked immunosorbent assay (ELISA). The levels of oxidative stress indicators in the corpus cavernosum (CC) were measured by corresponding kits, and histological changes in the CC were observed by hematoxylin-eosin (HE) and Masson staining. Additionally, the apoptosis index, caspase-3, caspase-9, and eNOS expression, and mitochondrial membrane potential (MMP) were also detected. Furthermore, quantitative polymerase chain reaction (qPCR) and western blot assays were conducted to determine the NOS, TGF-β1 mRNA expression, ERK1/2, eNOS, JNK phosphorylation, and arginase II protein expression.

Results

The erectile function test revealed that erectile dysfunction (ED) was alleviated in the DMED rats following treatment with GLP. Moreover, GLP upregulated the T and cGMP content, improved the oxidative stress and histological injuries of CC, and also inhibited the apoptosis and MMP loss of penile tissues in DMED rats. Furthermore, GLP treatment enhanced the mRNA expression of NOS and TGF-β1 and suppressed the phosphorylation of ERK1/2, eNOS, and JNK, as well as the protein expression of arginase II in DMED rats.

Conclusions

GLP ameliorated DMED by repairing the CC pathological damage and upregulating NOS expression and ERK/JNK phosphorylation, indicating that GLP may be a candidate drug for DMED therapy.

Thermodynamic approach for the understanding of the kinetics of heat effects induced by structural relaxation of metallic glasses

We present a novel approach to the understanding of heat effects induced by structural relaxation of metallic glasses. The key idea consists in the application of a general thermodynamic equation for the entropy change due to the evolution of a non-equilibrium part of a complex system. This non-equilibrium part is considered as a defect subsystem of glass and its evolution is governed by local thermoactivated rearrangements with a Gibbs free energy barrier proportional to the high-frequency shear modulus. The only assumption on the nature of the defects is that they should provide a reduction of the shear modulus-a diaelastic effect. This approach allows to determine glass entropy change upon relaxation. On this basis, the kinetics of the heat effects controlled by defect-induced structural relaxation is calculated. A very good agreement between the calculation and specially performed calorimetric and shear modulus measurements on three metallic glasses is found.

Establishment of mouse line showing inducible priapism-like phenotypes

Purpose

Penile research is expected to reveal new targets for treatment and prevention of the complex mechanisms of its disorder including erectile dysfunction (ED). Thus, analyses of the molecular processes of penile ED and continuous erection as priapism are essential issues of reproductive medicine.

Methods

By performing mouse N-ethyl-N-nitrosourea mutagenesis and exome sequencing, we established a novel mouse line displaying protruded genitalia phenotype (PGP; priapism-like phenotype) and identified a novel Pitpna gene mutation for PGP. Extensive histological analyses on the Pitpna mutant and intracavernous pressure measurement (ICP) and liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI/MS)/MS analyses were performed.

Results

We evaluated the role of phospholipids during erection for the first time and showed the mutants of inducible phenotypes of priapism. Moreover, quantitative analysis using LC-ESI/MS/MS revealed that the level of phosphatidylinositol (PI) was significantly lower in the mutant penile samples. These results imply that PI may contribute to penile erection by PITPα.

Conclusions

Our findings suggest that the current mutant is a mouse model for priapism and abnormalities in PI signaling pathways through PITPα may lead to priapism providing an attractive novel therapeutic target in its treatment.

Role of dietary calcium and its possible mechanism against metabolic disorders: A concise review

The global prevalence of metabolic disorders including hypertension, dyslipidemia, insulin resistance, nonalcoholic fatty liver, and cardiovascular diseases seemed to affect people of all ages cutting across the national, economic, and demographic barrier. Therefore, the prevention of metabolic disorders is considered of paramount importance. The dietary role of nutrients including vitamins and minerals is one of the recommended preventive measures against metabolic disorders in modern society. Recently, dietary calcium, a common nutrient not only showed a beneficial effect against obesity through weight management, but also gained great attention against the risk of metabolic disorders. Though dietary calcium shows several beneficial effects against metabolic disorders but some inconsistent results were also reported. So, the present review aims to extract recent knowledge as well as their possible underlying mechanisms regarding the role of dietary calcium against metabolic disorders. The present review also discusses the negative impact as well as prospect of calcium intake on health issues. In summary, high calcium diet prevents the harmful consequences of metabolic disorders by regulating hormonal actions, alteration in intracellular calcium level, renin-angiotensin system, intestinal fat absorption, fecal fat excretion, lipid metabolism, carbohydrate metabolism, inflammation, and oxidative stress which together improve the metabolic health of an individual. PRACTICAL APPLICATIONS: Metabolic disorder is a global health issue across all sections of society and is growing rapidly in spite of several attempts by the scientific community to prevent it. Recently dietary calcium gained great attention in the last few years for its role in the management and treatment of metabolic disorders. The current review highlights the beneficial role of dietary calcium against several metabolic complications by exploring their underlying mechanisms at cellular level. This study will provide valuable information regarding the recommendation of dietary calcium in health policy as well as its inclusion in the dietary chart through calcium-rich foods and/or taking calcium supplements which can be a useful approach in preventing the risk of metabolic disorder depending on the health status of an individual.

Uncovering the mechanisms of leech and centipede granules in the treatment of diabetes mellitus-induced erectile dysfunction utilising network pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes mellitus-induced erectile dysfunction (DMED) is one of the most common complications of diabetes mellitus. Leech and centipede granules (LCG) have traditionally been used as blood-activating agents in various ethnomedicinal systems of East Asia, especially in China. It is often used to regulate bodily functions and considered as adjuvant therapy for promoting blood circulation, alleviating blood coagulation, activating meridians, and relieving stasis.

AIM OF THE STUDY

This study aimed to identify potential genes and mechanisms of LCG on DMED from the network pharmacological perspective.

MATERIALS AND METHODS

The active components of LCG were identified by UHPLC-Q-TOF-MS, TCMID, and the BATMAN-TCM databases, and the disease targets of DMED were obtained from the DisGeNET, CooLGeN, GeneCards databases. After identifying DMED targets of LCG, a protein-protein interaction (PPI) network was constructed. Hub genes and significant modules were identified via the MCODE plug-in of Cytoscape software. Then, significant signaling pathways of the modules were identified using the Metascape database. The probable interaction mode of compounds-hub genes is examined using Molecular Operating Environment (MOE) docking software. Besides, we investigated the effects and mechanisms of LCG on improving erectile function in the streptozotocin (STZ)-induced diabetic rats model.

RESULTS

Combined UHPLC-Q-TOF-MS analysis with network pharmacology study, 18 active compounds were selected for target prediction. There are 97 common target genes between LCG and DMED. Enrichment of the KEGG pathway mainly involves in the calcium signaling pathway, NF-kappa B signaling pathway, cGMP-PKG signaling pathway, HIF-1 signaling pathway, PI3K-Akt signaling pathway, and mTOR signaling pathway. Nine hub genes were regulated by LCG in DMED, including CXCL8, NOS3, CRH, TH, BDNF, DRD4, ACE, CNR1, and HTR1A. The results of molecular docking analysis showed that the tyrosin, ursolic acid, and L-Histidine has a relatively stable interaction with corresponding hub genes via generating hydrogen bonds, H-π, and π-π interactions. Significantly, the results in docking predicted a higher affinity of vardenafil to the hub genes compared to the tyrosin, ursolic acid, and L-Histidine. Furthermore, LCG increased the testosterone, erection frequency, the ratio of ICP and MAP, SOD, cGMP, cAMP as well as decreased the MDA, and AGEs expression levels. And, LCG ameliorated the histological change of penile tissues in DMED rats. Hence, LCG attenuates oxidative stress, increases NO production; For the mechanism exploration, LCG could significantly upregulate the mRNA and protein expression of CNR1, NOS3, CRH, TH, BDNF, and DRD4, whereas CXCL8, ACE, and HTR1A levels were significantly higher than those in the DMED group. Moreover, LCG activates the NO/cGMP/PKG pathway, PI3K/Akt/nNOS pathway, cAMP/PKA pathway, and inhibits the HIF-1α/mTOR pathway to improve erectile function.

CONCLUSIONS

Our results suggest that LCG maybe offer a new therapeutic basis for the treatment of DMED via altering the gene expression of involved metabolic pathways.

Diagnostic Criteria for Metabolic Syndrome in Diet-Induced Rodent Models: A Systematic Review

BACKGROUND

Thousands of publications in recent years have addressed the induction of metabolic syndrome (MetS) in rodents. However, the criteria and the reference values for diagnosing this disease have not been defined.

OBJECTIVE

Our main objective was to carry out a systematic review to gather evidence about the criteria for biochemical and anthropometric parameters in which scientific studies have relied on to report that rats developed MetS from a previous dietary manipulation.

METHODS

We compiled characteristics and findings of diet-induced MetS with high-fat, high-carbohydrate, high-fat/high-carbohydrates, and cafeteria diet from PubMed and Science Direct databases published in the last 5 years.

RESULTS

The results on the principal determinants for the syndrome, published in the reviewed articles, were chosen to propose reference values in the rat models of food induction.

CONCLUSION

The values obtained will serve as reference cut-of points in the development of the disease; in addition, the compilation of data will be useful in planning and executing research protocols in animal models.

XingNaoJing injection ameliorates cerebral ischaemia/reperfusion injury via SIRT1-mediated inflammatory response inhibition

Context: XingNaoJing injection (XNJ), extracted from a traditional compound Chinese medicine Angong niuhuang pill, is well known for treating stroke in the clinic, but the specific effects and mechanisms remain unclear.Objective: We investigated the mechanistic basis for the protective effect of XNJ on cerebral ischaemia/reperfusion (I/R) injury.Materials and methods: Five groups of 10 SD rats underwent 2 h of middle cerebral artery occlusion (MCAO) followed by 24 h reperfusion. XNJ at 10 and 15 mL/kg was intraperitoneally administered 24 h before ischaemia and at the onset of reperfusion respectively. The silent information regulator 1 (SIRT1) inhibitor EX527 was intracerebroventricularly injected 0.5 h before reperfusion. Cerebral infarction size, neurological scores, morphological changes, and expression levels of inflammatory mediators and SIRT1 were measured. Furthermore, human brain microvascular endothelial cells (HBMECs) were subjected to 3 h oxygen and glucose deprivation (OGD) followed by 24 h reoxygenation to mimic cerebral I/R in vitro. EX527 pre-treatment occurred 1 h before OGD. SIRT1 and inflammatory mediator levels were analyzed.Results: Both XNJ doses significantly decreased cerebral infarct area (40.11% vs. 19.66% and 9.87%) and improved neurological scores and morphological changes. Inflammatory mediator levels were remarkably decreased in both model systems after XNJ treatment. XNJ also enhanced SIRT1 expression. Notably, the SIRT1 inhibitor EX527 attenuated the XNJ-mediated decrease in inflammation in vivo and in vitro.Conclusions: XNJ improved cerebral I/R injury through inhibiting the inflammatory response via the SIRT1 pathway, which may be a useful target in treating cerebral I/R injury.

Exercise and caloric restriction improve cardiovascular and erectile function in rats with metabolic syndrome

The aim of this study is to examine the possible benefits of exercise and caloric restriction (CR) on cardiovascular hemodynamics, erectile function, and antioxidant system in metabolic syndrome (MS). Sixty male Spraque-Dawley rats were divided into five groups; control, MS, MS + CR, MS + exercise (EXC), and MS + CR + EXC. To induce MS, 10% fructose solution was applied for 3 months. Thereafter, in CR groups calorie was restricted 40% and in EXC groups swimming was performed for 6 weeks. Body weight, blood glucose, and blood pressure (BP) levels were measured before and after MS induction and at the end of the experiment. After decapitation, tumor necrosis factor (TNF)-α, adiponectin (ADP), and plasminogen activator inhibitor (PAI)-1 levels were investigated in blood, oxidative stress parameters were examined in heart, aorta, and corpus cavernosum (CC) tissues. Isometric contraction in isolated tissue bath was studied in aorta and CC tissues. Animals subjected to exercise and CR had decreased BP and blood glucose levels. Impaired contraction-relaxation responses in MS group were improved with exercise and CR. MS-induced increase in TNF-α, PAI-1, malondialdehyde (MDA), and decrease in ADP, glutathione (GSH), and superoxide dismutase (SOD) were normalized with exercise and CR. Exercise and CR may be beneficial against changes in cardiovascular hemodynamics caused by MS.

A Systematic Review on Rho-Kinase as a Potential Therapeutic Target for the Treatment of Erectile Dysfunction

Background

Erectile dysfunction (ED) is a common clinical condition with limited treatment options. The main aim of the present systematic review was to synthesize information on Rho-kinase as a novel therapeutic approach for the treatment of ED.

Methods

We performed a systematic literature study in PubMed, Google Scholar and Scopus. Included studies were original articles studied the role of Rho-kinase in the pathogenesis and/or new treatment approach for ED in animal models and clinical studies, published between 2014 and 2019. Data derived from each study were study design used, interventions applied and main treatment outcomes. The quality of the selected articles was assessed by CAMARADES criteria and data were analyzed using descriptive statistics.

Results

A total of 1067 original articles were retrieved in the given period and eighteen papers met our inclusion criteria. Five articles explain the role of Rho-kinase in ED pathogenesis using different models such as cavernous nerve crush injury, heart failure-induced ED, vasculogenic and post-radical prostatectomy ED, diabetes-induced ED and age-related ED. Other ten papers explain the role of novel drugs evaluated for ED treatment by targeting Rho-kinase as a new approach for ED therapy. The rest three papers discuss the role of plant extracts used by traditional society for the treatment of ED and assess their potential function in targeting Rho-kinase in animal models. The penile erectile functional index has shown that the ratio of intracavernosal pressure to mean arterial pressure (ICP/MAP) was decreased due to age and various chronic diseases. Whilst, ROCK I and ROCK II expression were increased. Western blot findings have also shown that ROCK II and MYPT-1 phosphorylation rates increased in cavernous tissue after ED induction. Besides, compounds which can inhibit the action of Rho-kinase activity showed relaxation of the corpus cavernosum, decrease in corporal fibrosis, and alleviate increased apoptosis and caspase-3 activity in an NO-independent manner. Moreover, histological and molecular dysregulation have been improved by inhibition of Rho-kinase.

Conclusion

Targeting Rho-kinase may be a possible target for the treatment of ED secondary to specific causes, and Rho-kinase inhibitors may be a new drug family for the treatment of ED. However, this requires further studies for in-depth understanding.

Proteomic analysis of oxidative stress response in human umbilical vein endothelial cells (HUVECs): role of heme oxygenase 1 (HMOX1) in hypoxanthine-induced oxidative stress in HUVECs

Background

Erectile dysfunction (ED) is a well-known complication of diabetes, affecting up to 75% of diabetic men. Although the etiology of diabetic ED is multifactorial, endothelial dysfunction is considered to be a pillar of its pathophysiology. Endothelial dysfunction is caused by the harmful effects of high glucose levels and increased oxidative stress on the endothelial cells that comprise the vascular endothelium. The aim of this study was to identify the proteomic changes caused by high glucose-induced oxidative stress and explore the role of heme oxygenase 1 (HMOX1) in it.

Methods

The cellular proteomic response to hypoxanthine-induced oxidative stress in human umbilical vein endothelial cells (HUVECs) was analyzed by isobaric tags for relative and absolute quantitation (iTRAQ) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Differentially expressed proteins (DEPs) were analyzed through Network and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Further validation assays was performed to validate the role of HMOX1.

Results

The results showed that 66 and 76 DEPs were markedly upregulated and downregulated, respectively, for HUVECs oxidative stress. Among these proteins, we verified eight dysregulated genes by quantitative reverse transcription PCR, including nucleolin (NCL), X-ray repair cross-complementing protein 6 (XRCC6), ubiquinol-cytochrome C reductase binding protein (UQCRB), non-POU domain containing octamer binding (NONO), heme oxygenase 1 (HMOX1), nucleobindin 1 (NUCB1), DEK, and chromatin target of prmt1 (CHTOP). Further, using overexpression and genetic knockdown approaches, we found that HMOX1 was critical for the oxidative stress response in HUVECs.

Conclusions

We found that HMOX1 was closely related to the oxidative stress response induced by hypoxanthine. To the best of our knowledge, this study is the first overview of the responses of HUVECs to oxidative stress. The findings will contribute to analyses of the detailed molecular mechanisms involved in the pathogenesis of endothelial dysfunction and related molecular mechanisms in ED patients.

Research of stroke combined hyperlipidemia-induced erectile dysfunction in rat model

Objective: The study was aimed to evaluate the influences of erectile dysfunction (ED) in a rat model of stroke combined with hyperlipidemia (HLP). Methods: Male Sprague-Dawley rats were divided into control and hyperlipidemia (HLP) groups. HLP model was constructed by feeding with high-fat and cholesterol diets. Serum levels of total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), triglyceride (TG), and non-HDL were identified to check the model was success. Stroke model was established by FeCl₃. ICP/MAP value was detected to evaluate the erectile function of rats. Serum level of lipoproteins and the expressions of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) were detected by ELISA. Hematoxylin-eosin (HE) staining of corpus cavernosum and measurement of penis length were utilized to assessment erectile function. Western blot was used. Results: TC, TG, LDL, and non-HDL-C in serum were up-regulated, while HDL level was attenuated. After treatment, the serum lipid level recovered. From the ICP/MAP values, the erectile function of both two treatment groups recovered. The expression of PDE5A was up-regulated, while the levels of eNOS and cGMP were suppressed after surgery. The length of penis was decreased, and corpus cavernosum was damaged following HLP and stroke. However, the erectile function was recovered after treatment. Conclusion: Stroke combined HLP caused ED through NO-cGMP-PDE5 pathway.

Effects of a high energy density diet in the "corpus cavernosum" of mice

Erectile dysfunction is a common condition that affects men over age 40. It is highly related to obesity. The corpus cavernosum is the most important structure involved in erection. The aim of this study was to evaluate the structure of the corpus cavernosum of mice fed with a high energy density diet (HED). At 3 months of age, male C57BL/6 mice were fed with a HED diet (50% lipids) or standard chow (SC) diet (10% lipids) for 14 weeks. Afterwards, the animals were euthanized and the corpus cavernosum was analyzed through stereology. Statistical significance was calculated by the student's t-test (p < 0.05). The group fed with HED diet showed higher values of body weight, blood pressure and higher rates of cholesterol, triglycerides, and glucose from the second week to the end of the experiment. The HED group showed a significant increase in the connective tissue (15%) and a decrease in smooth muscle fibers (41%). The testosterone concentration in the HED group was 63% lower than in SC animals. Animals fed with a HED presented reduced testosterone serum levels and morphological changes on the corpus cavernosum, which may be related to erectile dysfunction.

CircRUNX2 through has-miR-203 regulates RUNX2 to prevent osteoporosis

Objective

We aimed to discover the molecular mechanism of hsa_circ_0076694 (circRUNX2) on osteogenic differentiation. We also explored the interaction between circRUNX2, miR‐203 and RUNX2.

Methods

Clinical samples obtained from femoral neck fracture patients’ bone tissues were used to collect circRUNX2, miR‐203, and RUNX2 expression data, while their expression changes were observed in human bone mesenchymal stem cells (hBMSCs) during osteogenic differentiation. QRT‐PCR and Western blot were used to analyse levels of RNAs and proteins. Biotin pull down, RIP, RNA FISH, and Dual‐Luciferase Reporter assays demonstrated the relationship between circRUNX2, miR‐203, and RUNX2. ALP and ARS staining were used to measure the degree of osteogenic differentiation under the control of circRUNX2, miR‐203.

Results

CircRUNX2 were down‐regulated in osteoporotic patients’ bone tissues. CircRUNX2 could inhibit miR‐203 expression by sponging miR‐203. MiR‐203 inhibited osteogenic differentiation by targeting the 3′‐UTR of RUNX2 and down‐regulate RUNX2 expression. Overexpression of circRUNX2 promoted the expression of osteogenic differentiation‐related proteins such as RUNX2, OCN, OPN, BSP, and prevented osteoporosis.

Conclusion

circRUNX2 could sponge miR‐203 and enhance RUNX2 expression, thus circRUNX2 prevents osteoporosis and may provide a novel therapeutic strategy for it.

Xingnaojing Injection Protects against Cerebral Ischemia Reperfusion Injury via PI3K/Akt-Mediated eNOS Phosphorylation

Xingnaojing (XNJ) injection, derived from traditional Chinese medicine formulation, has a protective effect against stroke, but the underlying mechanism is unclear, which severely limited its clinical application. This research aims to elucidate the role and mechanism of XNJ in reducing cerebral ischemic reperfusion (I/R) injury. Rats received 2 h cerebral ischemia followed by reperfusion of 24 h and were intraperitoneally given 5, 10, or 15 ml/kg XNJ 24 h before ischemia and at the onset of reperfusion, respectively. TTC staining, HE staining, and neurological score were implied to evaluate the effectiveness of XNJ. The protein expressions of PI3K/Akt and eNOS signaling were measured. Experiments were further performed in human brain microvascular endothelial cells (HBMECs) to investigate the protective mechanisms of XNJ. HBMECs were subjected to 3 h oxygen and glucose deprivation following 24 h of reoxygenation (OGD) to mimic cerebral I/R in vitro. PI3K inhibitor LY294002 was added with or without the preconditioning of XNJ. Multiple methods including western blot, immunofluorescence, DAPI staining, JC-1, and flow cytometry were carried out to evaluate the effect of XNJ on HBMECs. XNJ could improve rat cerebral ischemic injury and OGD induced HBMECs apoptosis. In vivo and in vitro researches indicated that the mechanism might be relevant to the activation of PI3K/Akt/eNOS signaling.