1
|
Guan G, Cannon RD, Coates DE, Mei L. Effect of the Rho-Kinase/ROCK Signaling Pathway on Cytoskeleton Components. Genes (Basel) 2023; 14:272. [PMID: 36833199 PMCID: PMC9957420 DOI: 10.3390/genes14020272] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/10/2023] [Accepted: 01/16/2023] [Indexed: 01/22/2023] Open
Abstract
The mechanical properties of cells are important in tissue homeostasis and enable cell growth, division, migration and the epithelial-mesenchymal transition. Mechanical properties are determined to a large extent by the cytoskeleton. The cytoskeleton is a complex and dynamic network composed of microfilaments, intermediate filaments and microtubules. These cellular structures confer both cell shape and mechanical properties. The architecture of the networks formed by the cytoskeleton is regulated by several pathways, a key one being the Rho-kinase/ROCK signaling pathway. This review describes the role of ROCK (Rho-associated coiled-coil forming kinase) and how it mediates effects on the key components of the cytoskeleton that are critical for cell behaviour.
Collapse
Affiliation(s)
- Guangzhao Guan
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
- Department of Oral Diagnostic and Surgical Sciences, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Richard D. Cannon
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| | - Dawn E. Coates
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
| | - Li Mei
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin 9016, New Zealand
- Department of Oral Sciences, Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin 9016, New Zealand
| |
Collapse
|
2
|
Pierre CJ, Azeez TA, Rossetti ML, Gordon BS, La Favor JD. Long-term administration of resveratrol and MitoQ stimulates cavernosum antioxidant gene expression in a mouse castration model of erectile dysfunction. Life Sci 2022; 310:121082. [PMID: 36252696 PMCID: PMC9746260 DOI: 10.1016/j.lfs.2022.121082] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 10/01/2022] [Accepted: 10/11/2022] [Indexed: 11/09/2022]
Abstract
AIMS Erectile dysfunction is a common complication within many pathological conditions associated with low testosterone. Testosterone deficiency increases oxidative stress in the penile tissue that contributes to endothelial dysfunction and subsequent erectile dysfunction. Current therapies do not ameliorate oxidative stress so targeting oxidative stress may improve erectile dysfunction. Resveratrol and MitoQ are two prospective drugs that have antioxidant-like properties and may be useful to improve erectile dysfunction induced by androgen deprivation. MATERIALS AND METHODS We castrated 12-week-old male C57BL/6 mice and performed an eight-week intervention with oral delivery of resveratrol or MitoQ at low and high doses. We assessed vascular reactivity of the corpus cavernosum and internal pudendal arteries (IPA) through dose-dependent responses to vasodilatory, vasocontractile, and neurogenic stimuli in a myograph system. We performed qRT-PCR to measure expression changes of 18 antioxidant genes in the corpus cavernosum. KEY FINDINGS Castration significantly impaired erectile function via impaired endothelial-dependent and-independent relaxation, and increased constriction of the corpus cavernosum, and induced severe endothelial dysfunction of the IPA. Castration decreased expression of 8 of the antioxidant genes investigated. Resveratrol and MitoQ were ineffective in reversing the effects of androgen deprivation on vascular reactivity, however high-dose resveratrol treatment upregulated several key antioxidant genes, including Cat, Sod1, Gstm1, and Prdx3. SIGNIFICANCE Our findings suggest that oral resveratrol and MitoQ treatment may provide protection to the corpus cavernosum under androgen deprived conditions by stimulating endogenous antioxidant systems. However, they may need to be paired with vasoactive drugs to reverse erectile dysfunction under androgen deprived conditions.
Collapse
Affiliation(s)
- Clifford J Pierre
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States
| | - Tooyib A Azeez
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States
| | - Michael L Rossetti
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States
| | - Bradley S Gordon
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States
| | - Justin D La Favor
- Department of Nutrition and Integrative Physiology, College of Health and Human Sciences, Florida State University, Tallahassee, FL, United States.
| |
Collapse
|
3
|
Lucas-Herald AK, Montezano AC, Alves-Lopes R, Haddow L, Alimussina M, O’Toole S, Flett M, Lee B, Amjad SB, Steven M, Brooksbank K, McCallum L, Delles C, Padmanabhan S, Ahmed SF, Touyz RM. Vascular dysfunction and increased cardiovascular risk in hypospadias. Eur Heart J 2022; 43:1832-1845. [PMID: 35567552 PMCID: PMC9113289 DOI: 10.1093/eurheartj/ehac112] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 12/30/2021] [Accepted: 02/15/2022] [Indexed: 11/30/2022] Open
Abstract
AIMS Hypogonadism is associated with cardiovascular disease. However, the cardiovascular impact of hypogonadism during development is unknown. Using hypospadias as a surrogate of hypogonadism, we investigated whether hypospadias is associated with vascular dysfunction and is a risk factor for cardiovascular disease. METHODS AND RESULTS Our human study spanned molecular mechanistic to epidemiological investigations. Clinical vascular phenotyping was performed in adolescents with hypospadias and controls. Small subcutaneous arteries from penile skin from boys undergoing hypospadias repair and controls were isolated and functional studies were assessed by myography. Vascular smooth muscle cells were used to assess: Rho kinase, reactive oxygen species (ROS), nitric oxide synthase/nitric oxide, and DNA damage. Systemic oxidative stress was assessed in plasma and urine. Hospital episode data compared men with a history of hypospadias vs. controls. In adolescents with hypospadias, systolic blood pressure (P = 0.005), pulse pressure (P = 0.03), and carotid intima-media thickness standard deviation scores (P = 0.01) were increased. Arteries from boys with hypospadias demonstrated increased U46619-induced vasoconstriction (P = 0.009) and reduced acetylcholine-induced endothelium-dependent (P < 0.0001) and sodium nitroprusside-induced endothelium-independent vasorelaxation (P < 0.0001). Men born with hypospadias were at increased risk of arrhythmia [odds ratio (OR) 2.8, 95% confidence interval (CI) 1.4-5.6, P = 0.003]; hypertension (OR 4.2, 95% CI 1.5-11.9, P = 0.04); and heart failure (OR 1.9, 95% CI 1.7-114.3, P = 0.02). CONCLUSION Hypospadias is associated with vascular dysfunction and predisposes to hypertension and cardiovascular disease in adulthood. Underlying mechanisms involve perturbed Rho kinase- and Nox5/ROS-dependent signalling. Our novel findings delineate molecular mechanisms of vascular injury in hypogonadism, and identify hypospadias as a cardiovascular risk factor in males.
Collapse
Affiliation(s)
- Angela K Lucas-Herald
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Centre for Research Excellence, University of Glasgow, 126 University Avenue, Glasgow G12 8TA, UK
- Developmental Endocrinology Research Group, School of Medicine, Dentistry and Nursing, University of Glasgow, Royal Hospital for Children, 1345 Govan Road, Glasgow G45 8TF, UK
| | - Augusto C Montezano
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Centre for Research Excellence, University of Glasgow, 126 University Avenue, Glasgow G12 8TA, UK
| | - Rheure Alves-Lopes
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Centre for Research Excellence, University of Glasgow, 126 University Avenue, Glasgow G12 8TA, UK
| | - Laura Haddow
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Centre for Research Excellence, University of Glasgow, 126 University Avenue, Glasgow G12 8TA, UK
| | - Malika Alimussina
- Developmental Endocrinology Research Group, School of Medicine, Dentistry and Nursing, University of Glasgow, Royal Hospital for Children, 1345 Govan Road, Glasgow G45 8TF, UK
| | - Stuart O’Toole
- Department of Pediatric Surgery, Royal Hospital for Children, 1345 Govan Road, Glasgow G45 8TF, UK
| | - Martyn Flett
- Department of Pediatric Surgery, Royal Hospital for Children, 1345 Govan Road, Glasgow G45 8TF, UK
| | - Boma Lee
- Department of Pediatric Surgery, Royal Hospital for Children, 1345 Govan Road, Glasgow G45 8TF, UK
| | - S Basith Amjad
- Department of Pediatric Surgery, Royal Hospital for Children, 1345 Govan Road, Glasgow G45 8TF, UK
| | - Mairi Steven
- Department of Pediatric Surgery, Royal Hospital for Children, 1345 Govan Road, Glasgow G45 8TF, UK
| | - Katriona Brooksbank
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Centre for Research Excellence, University of Glasgow, 126 University Avenue, Glasgow G12 8TA, UK
| | - Linsay McCallum
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Centre for Research Excellence, University of Glasgow, 126 University Avenue, Glasgow G12 8TA, UK
| | - Christian Delles
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Centre for Research Excellence, University of Glasgow, 126 University Avenue, Glasgow G12 8TA, UK
| | - Sandosh Padmanabhan
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Centre for Research Excellence, University of Glasgow, 126 University Avenue, Glasgow G12 8TA, UK
| | - S Faisal Ahmed
- Developmental Endocrinology Research Group, School of Medicine, Dentistry and Nursing, University of Glasgow, Royal Hospital for Children, 1345 Govan Road, Glasgow G45 8TF, UK
| | - Rhian M Touyz
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation Centre for Research Excellence, University of Glasgow, 126 University Avenue, Glasgow G12 8TA, UK
| |
Collapse
|
4
|
Krysiak R, Kowalcze K, Okopień B. The impact of hypotestosteronemia on cardiometabolic effects of atorvastatin in men with hypercholesterolemia: a pilot study. Coron Artery Dis 2021; 32:706-712. [PMID: 33826536 PMCID: PMC8912965 DOI: 10.1097/mca.0000000000001031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 01/25/2021] [Indexed: 12/02/2022]
Abstract
BACKGROUND Hypothyroidism, hyperprolactinemia, macroprolactinemia and low vitamin D status were found to impair pleiotropic effects of hypolipidemic agents. The aim of the current study was to investigate whether cardiometabolic effects of atorvastatin in men are determined by endogenous testosterone. METHODS We studied three groups of men matched for age, BMI, plasma lipids and blood pressure: 19 untreated subjects with low testosterone levels (group A), 19 normotestosteronemic men receiving testosterone preparations (group B) and 21 untreated men with testosterone levels within the reference range (group C). Because of coexistent hypercholesterolemia, all subjects were managed with atorvastatin (40 mg daily) for 6 months. Glucose homeostasis markers, plasma lipids, as well as circulating levels of testosterone, uric acid, high-sensitivity C-reactive protein (hsCRP), fibrinogen, homocysteine and 25-hydroxyvitamin D were determined at the beginning and at the end of the study. RESULTS At baseline, group A was more insulin-resistant and was characterized by higher levels of hsCRP, fibrinogen and homocysteine, and lower levels of 25-hydroxyvitamin D than the remaining groups of patients. Despite reducing total and low-density lipoprotein cholesterol and hsCRP levels in all treatment groups, this effect was stronger in groups B and C than in group A. In groups B and C, atorvastatin use was also associated with a decrease in uric acid, fibrinogen and homocysteine concentrations and with an increase in 25-hydroxyvitamin D levels. In group A, but not in the remaining groups, the drug decreased insulin sensitivity. CONCLUSION The obtained results suggest that untreated hypotestosteronemia may attenuate cardiometabolic effects of atorvastatin in men.
Collapse
Affiliation(s)
- Robert Krysiak
- Department of Internal Medicine and Clinical Pharmacology
| | - Karolina Kowalcze
- Department of Pediatrics in Bytom, School of Health Sciences in Katowice, Medical University of Silesia, Katowice, Poland
| | | |
Collapse
|
5
|
Hiremath DS, Geerling EC, Hai L, Narayan P. High levels of androgens cause chondrocyte accumulation and loss of smooth muscle in the mouse penile body†. Biol Reprod 2020; 102:1225-1233. [PMID: 32068232 DOI: 10.1093/biolre/ioaa023] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/12/2020] [Accepted: 02/14/2020] [Indexed: 11/14/2022] Open
Abstract
Androgens are essential for penile development and for maintaining penile structural and functional integrity. Loss of androgen levels or function results in a decrease in smooth muscle content, accumulation of adipocytes in the corpora cavernosa, and inhibition of erectile function. Our previous studies with a mouse model (KiLHRD582G) of constitutive luteinizing hormone receptor activity also showed structural abnormalities in the penis caused by a decrease in smooth muscle content, accumulation of chondrocytes, and sexual dysfunction. As KiLHRD582G mice exhibit very high levels of testosterone at all postnatal ages, the goal of this study was to determine if the elevated androgen levels were responsible for the morphological changes in the penis. Implantation of testosterone capsules in wild-type mice at neonatal (2 weeks) and postpubertal (5 weeks) ages resulted in the accumulation of chondrocytes in the corpora cavernosa of the adult animals. Mice implanted with testosterone capsules at 2 weeks of age exhibited a 4-fold increase in serum testosterone with a 1.5-fold loss of smooth muscle at 24 weeks of age. Collagen content was unchanged. Only 57% of testosterone implanted mice were fertile at 24 weeks of age. Mice implanted with testosterone capsules at 5 weeks of age showed no decrease in smooth muscle content at 24 weeks, although serum testosterone levels were elevated 5-fold. Implantation with dihydrotestosterone also resulted in chondrocyte accumulation and a 2-fold loss in smooth muscle content. Together, these studies demonstrate that supraphysiological levels of androgens cause structural changes in the penile corpora cavernosa and impair fertility.
Collapse
Affiliation(s)
- Deepak S Hiremath
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL, USA
| | - Elizabeth C Geerling
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL, USA
| | - Lan Hai
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL, USA
| | - Prema Narayan
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL, USA
| |
Collapse
|
6
|
Testosterone Deficiency and Endothelial Dysfunction: Nitric Oxide, Asymmetric Dimethylarginine, and Endothelial Progenitor Cells. Sex Med Rev 2019; 7:661-668. [DOI: 10.1016/j.sxmr.2019.02.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 02/12/2019] [Accepted: 02/13/2019] [Indexed: 12/15/2022]
|
7
|
Kong X, Jiang J, Cheng B, Jiang R. Effect of low androgen status on the expression of adenosine A 2A and A 2B receptors in rat penile corpus cavernosum. Andrologia 2019; 51:e13344. [PMID: 31206753 DOI: 10.1111/and.13344] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/16/2019] [Accepted: 05/20/2019] [Indexed: 02/06/2023] Open
Abstract
To investigate whether low androgen status affects erectile function by regulating the expression of adenosine A2A and A2B receptors in rat penile corpus cavernosum. Thirty-six 8-week-old male Sprague-Dawley rats were randomly divided into six groups: sham-operated group (4w-sham, 8w-sham), castration group (4w-cast, 8w-cast) and androgen replacement group (4w-cast+T, 8w-cast+T). The rats in the androgen replacement groups were subcutaneously injected with testosterone propionate (3 mg/kg) every other day after castration. The maximum intracavernous pressure/mean arterial pressure (ICPmax/MAP), the expression of A2A , A2B , AKT and eNOS and the concentrations of cAMP and cGMP in the corpus cavernosum were detected at the 4th and 8th weeks after the operation. The serum testosterone level and the ratio of ICPmax/MAP decreased significantly in the castration group as compared to other groups (p < 0.01). There was no significant difference in the expression of A2A receptor among groups, while the expression of A2B , AKT and eNOS and the concentrations of cAMP and cGMP in the castration group were significantly lower than in other groups (p < 0.01). Low androgen status inhibits the AKT/eNOS/cGMP signalling pathways and the production of cAMP in the corpus cavernosum of castrated rats by down-regulating the expression of A2B receptor, and results in decreased of ICPmax/MAP.
Collapse
Affiliation(s)
- XiangJun Kong
- Department of Urology, Nephropathy Clinical Medical Research Center of Sichuan Province, Affiliated Hospital, Southwest medical University, Luzhou, China
| | - Jun Jiang
- Department of Thyroid Surgery, Affiliated Hospital, Southwest Medical University, Luzhou, China
| | - Bo Cheng
- Department of Urology, Nephropathy Clinical Medical Research Center of Sichuan Province, Affiliated Hospital, Southwest medical University, Luzhou, China
| | - Rui Jiang
- Department of Urology, Nephropathy Clinical Medical Research Center of Sichuan Province, Affiliated Hospital, Southwest medical University, Luzhou, China
| |
Collapse
|
8
|
Yin J, Guo YM, Chen P, Xiao H, Wang XH, DiSanto ME, Zhang XH. Testosterone regulates the expression and functional activity of sphingosine-1-phosphate receptors in the rat corpus cavernosum. J Cell Mol Med 2017; 22:1507-1516. [PMID: 29266713 PMCID: PMC5824404 DOI: 10.1111/jcmm.13416] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2016] [Accepted: 09/12/2017] [Indexed: 01/29/2023] Open
Abstract
The bioactive lipid sphingosine‐1‐phosphate (S1P) regulates smooth muscle (SM) contractility predominantly via three G protein‐coupled receptors. The S1P1 receptor is associated with nitric oxide (NO)‐mediated SM relaxation, while S1P2 & S1P3 receptors are linked to SM contraction via activation of the Rho‐kinase pathway. This study is to determine testosterone (T) modulating the expression and functional activity of S1P receptors in corpus cavernosum (CC). Adult male Sprague‐Dawley rats were randomly divided into three groups: sham‐operated controls, surgical castration and T supplemented group. Serum S1P levels were detected by high‐performance liquid chromatography. The expression of S1P1‐3 receptors and sphingosine kinases was detected by real‐time RT‐PCR. In vitro organ bath contractility and in vivo intracavernous pressure (ICP) measurement were also performed. T deprivation significantly decreased ICP rise. Meanwhile, surgical castration induced a significant increase in serum S1P level and the expression of S1P2‐3 receptors by twofold (P < 0.05) but a decrease in the expression of S1P1 receptor. Castration also augmented exogenous phenylephrine (PE), S1P, S1P1,3 receptor agonist FTY720‐P contractility and S1P2‐specific antagonist JTE013 relaxation effect. T supplemented could restore the aforementioned changes. We provide novel data that castration increased serum S1P concentration and up‐regulated the expression of S1P2‐3 receptors in CC. Consistently, agonizing S1P receptors induced CCSM contraction and antagonizing mediated relaxation were augmented. This provides the first clear evidence that S1P system dysregulation may contribute to hypogonadism‐related erectile dysfunction (ED), and S1P receptors may be expected as a potential target for treating ED.
Collapse
Affiliation(s)
- Jing Yin
- Department of Rehabilitation, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yu-Ming Guo
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Ping Chen
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - He Xiao
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Xing-Huan Wang
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Michael E DiSanto
- Surgery and Biomedical Sciences, Cooper Medical School of Rowan University, Camden, NJ, USA
| | - Xin-Hua Zhang
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| |
Collapse
|
9
|
Yin J, Guo YM, Chen P, Xiao H, Wang XH, DiSanto ME, Zhang XH. Testosterone regulates the expression and functional activity of sphingosine-1-phosphate receptors in the rat corpus cavernosum. J Cell Mol Med 2017. [DOI: 10.1111/jcmm.13416 29266713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Jing Yin
- Department of Rehabilitation; Zhongnan Hospital of Wuhan University; Wuhan China
| | - Yu-ming Guo
- Department of Urology; Zhongnan Hospital of Wuhan University; Wuhan China
| | - Ping Chen
- Department of Urology; Zhongnan Hospital of Wuhan University; Wuhan China
| | - He Xiao
- Department of Urology; Zhongnan Hospital of Wuhan University; Wuhan China
| | - Xing-huan Wang
- Department of Urology; Zhongnan Hospital of Wuhan University; Wuhan China
| | - Michael E DiSanto
- Surgery and Biomedical Sciences; Cooper Medical School of Rowan University; Camden NJ USA
| | - Xin-hua Zhang
- Department of Urology; Zhongnan Hospital of Wuhan University; Wuhan China
| |
Collapse
|
10
|
Musicki B, Karakus S, Akakpo W, Silva FH, Liu J, Chen H, Zirkin BR, Burnett AL. Testosterone replacement in transgenic sickle cell mice controls priapic activity and upregulates PDE5 expression and eNOS activity in the penis. Andrology 2017; 6:184-191. [PMID: 29145710 DOI: 10.1111/andr.12442] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 08/30/2017] [Accepted: 10/04/2017] [Indexed: 01/02/2023]
Abstract
Sickle cell disease (SCD)-associated priapism is characterized by decreased nitric oxide (NO) signaling and downregulated phosphodiesterase (PDE)5 protein expression and activity in the penis. Priapism is also associated with testosterone deficiency, but molecular mechanisms underlying testosterone effects in the penis in SCD are not known. Given the critical role of androgens in erection physiology and NO synthase (NOS)/PDE5 expression, we hypothesized that testosterone replacement to eugonadal testosterone levels reduces priapism by reversing impaired endothelial (e)NOS activity and molecular abnormalities involving PDE5. Adult male transgenic Berkeley sickle cell (Sickle) and wild-type (WT) mice were implanted with testosterone pellets, which release 1.2 μg testosterone/day for 21 days, or vehicle. After 21 days, animals underwent erectile function assessment followed by collection of blood for serum testosterone measurements, penes for molecular analysis, and seminal vesicles as testosterone-responsive tissue. Serum testosterone levels were measured by radioimmunoassay; protein expressions of PDE5, α-smooth muscle actin, eNOS and nNOS, and phosphorylation of PDE5 at Ser-92, eNOS at Ser-1177, neuronal (n) NOS at Ser-1412, and Akt at Ser-473 were measured by Western blot in penile tissue. Testosterone treatment reversed downregulated serum testosterone levels and increased (p < 0.05) the weight of seminal vesicles in Sickle mice to levels comparable to that of WT mice, indicating restored testosterone levels in Sickle mice. Testosterone treatment reduced (p < 0.05) prolonged detumescence in Sickle mice and normalized downregulated P-PDE5 (Ser-92), PDE5, P-eNOS (Ser-1177), and P-Akt (Ser-473) protein expressions in the Sickle mouse penis. Testosterone treatment did not affect P-nNOS (Ser-1412), eNOS, nNOS, or α-smooth muscle actin protein expressions in the Sickle mouse penis. In conclusion, in the mouse model of human SCD, increasing testosterone to eugonadal levels reduced priapic activity and reversed impaired Akt/eNOS activity and PDE5 protein expression in the penis.
Collapse
Affiliation(s)
- B Musicki
- The James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - S Karakus
- The James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - W Akakpo
- The James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - F H Silva
- The James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - J Liu
- Department of Biochemistry and Molecular Biology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - H Chen
- Department of Biochemistry and Molecular Biology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - B R Zirkin
- Department of Biochemistry and Molecular Biology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - A L Burnett
- The James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, MD, USA
| |
Collapse
|
11
|
Translational Perspective on the Role of Testosterone in Sexual Function and Dysfunction. J Sex Med 2017; 13:1183-98. [PMID: 27436075 DOI: 10.1016/j.jsxm.2016.06.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 05/13/2016] [Accepted: 06/09/2016] [Indexed: 12/31/2022]
Abstract
INTRODUCTION The biological importance of testosterone is generally accepted by the medical community; however, controversy focuses on its relevance to sexual function and the sexual response, and our understanding of the extent of its role in this area is evolving. AIM To provide scientific evidence examining the role of testosterone at the cellular and molecular levels as it pertains to normal erectile physiology and the development of erectile dysfunction and to assist in guiding successful therapeutic interventions for androgen-dependent sexual dysfunction. METHODS In this White Paper, the Basic Science Committee of the Sexual Medicine Society of North America assessed the current basic science literature examining the role of testosterone in sexual function and dysfunction. RESULTS Testosterone plays an important role in sexual function through multiple processes: physiologic (stimulates activity of nitric oxide synthase), developmental (establishes and maintains the structural and functional integrity of the penis), neural (development, maintenance, function, and plasticity of the cavernous nerve and pelvic ganglia), therapeutically for dysfunctional regulation (beneficial effect on aging, diabetes, and prostatectomy), and phosphodiesterase type 5 inhibition (testosterone supplement to counteract phosphodiesterase type 5 inhibitor resistance). CONCLUSION Despite controversies concerning testosterone with regard to sexual function, basic science studies provide incontrovertible evidence for a significant role of testosterone in sexual function and suggest that properly administered testosterone therapy is potentially advantageous for treating male sexual dysfunction.
Collapse
|
12
|
Liu L, Li E, Li F, Luo L, Zhao S, Kang R, Luo J, Zhao Z. Effect of Testosterone on the Phenotypic Modulation of Corpus Cavernosum Smooth Muscle Cells in a Castrated Rat Model. Urology 2017; 103:273.e1-273.e6. [PMID: 28214569 DOI: 10.1016/j.urology.2017.02.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 02/03/2017] [Accepted: 02/08/2017] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To investigate the effect of testosterone (T) on the phenotypic modulation of corpus cavernosum smooth muscle (CCSM) cells in a castrated rat model. MATERIALS AND METHODS Thirty male Sprague-Dawley rats were randomly divided into 3 groups: control, castration, and castration with T supplementation (castration + T). Erectile function, histologic change, and biochemical markers were assessed for phenotypic modulation of CCSM cells in corporal tissue. Moreover, the primary rat CCSM cells were isolated and examined by Western blot analysis. RESULTS Our data showed that serum T level, mean weight of the body, erectile function, and smooth muscle-to-collagen ratio were significantly decreased in the castration group compared with those in the control and castration + T groups. The expressions of CCSM cells' phenotypic markers, such as α-smooth muscle actin, calponin, and smooth muscle myosin heavy chain 11, were markedly lower, whereas osteopontin protein expression was significantly higher in castrated rats than in control and castrated + T rats. In addition, the immunofluorescence staining of α-smooth muscle actin and calponin markedly decreased in the primary CCSM cells of the castrated rats compared with the intensity of the control and the castration + T rats. CONCLUSION CCSM cells undergo phenotype modulation in castrated rats, whereas T reversed the alterations. T may play a key role in the phenotype modulation of CCSM cells.
Collapse
Affiliation(s)
- Luhao Liu
- Department of Urology and Andrology, Minimally Invasive Surgery Center, Guangdong Provincial Key Laboratory of Urology, The First Affiliated Hospital of Guangzhou Medical University. Guangzhou, Guangdong, China
| | - Ermao Li
- Department of Urology and Andrology, Minimally Invasive Surgery Center, Guangdong Provincial Key Laboratory of Urology, The First Affiliated Hospital of Guangzhou Medical University. Guangzhou, Guangdong, China
| | - Futian Li
- Department of Urology and Andrology, Minimally Invasive Surgery Center, Guangdong Provincial Key Laboratory of Urology, The First Affiliated Hospital of Guangzhou Medical University. Guangzhou, Guangdong, China
| | - Lianmin Luo
- Department of Urology and Andrology, Minimally Invasive Surgery Center, Guangdong Provincial Key Laboratory of Urology, The First Affiliated Hospital of Guangzhou Medical University. Guangzhou, Guangdong, China
| | - Shankun Zhao
- Department of Urology and Andrology, Minimally Invasive Surgery Center, Guangdong Provincial Key Laboratory of Urology, The First Affiliated Hospital of Guangzhou Medical University. Guangzhou, Guangdong, China
| | - Ran Kang
- Department of Urology and Andrology, Minimally Invasive Surgery Center, Guangdong Provincial Key Laboratory of Urology, The First Affiliated Hospital of Guangzhou Medical University. Guangzhou, Guangdong, China
| | - Jintai Luo
- Department of Urology and Andrology, Minimally Invasive Surgery Center, Guangdong Provincial Key Laboratory of Urology, The First Affiliated Hospital of Guangzhou Medical University. Guangzhou, Guangdong, China
| | - Zhigang Zhao
- Department of Urology and Andrology, Minimally Invasive Surgery Center, Guangdong Provincial Key Laboratory of Urology, The First Affiliated Hospital of Guangzhou Medical University. Guangzhou, Guangdong, China.
| |
Collapse
|
13
|
Zhang WH, Zhang XH. Clinical and preclinical treatment of urologic diseases with phosphodiesterase isoenzymes 5 inhibitors: an update. Asian J Androl 2017; 18:723-31. [PMID: 26620458 PMCID: PMC5000795 DOI: 10.4103/1008-682x.167721] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Phosphodiesterase isoenzymes 5 inhibitors (PDE5-Is) are the first-line therapy for erectile dysfunction (ED). The constant discoveries of nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) cell-signaling pathway for smooth muscle (SM) control in other urogenital tracts (UGTs) make PDE5-Is promising pharmacologic agents against other benign urological diseases. This article reviews the literature and contains some previously unpublished data about characterizations and activities of PDE5 and its inhibitors in treating urological disorders. Scientific discoveries have improved our understanding of cell-signaling pathway in NO/cGMP-mediated SM relaxation in UGTs. Moreover, the clinical applications of PDE5-Is have been widely recognized. On-demand PDE5-Is are efficacious for most cases of ED, while daily-dosing and combination with testosterone are recommended for refractory cases. Soluble guanylate cyclase (sGC) stimulators also have promising role in the management of severe ED conditions. PDE5-Is are also the first rehabilitation strategy for postoperation or postradiotherapy ED for prostate cancer patients. PDE5-Is, especially combined with α-adrenoceptor antagonists, are very effective for benign prostatic hyperplasia (BPH) except on maximum urinary flow rate (Q max ) with tadalafil recently proved for BPH with/without ED. Furthermore, PDE5-Is are currently under various phases of clinical or preclinical researches with promising potential for other urinary and genital illnesses, such as priapism, premature ejaculation, urinary tract calculi, overactive bladder, Peyronie's disease, and female sexual dysfunction. Inhibition of PDE5 is expected to be an effective strategy in treating benign urological diseases. However, further clinical studies and basic researches investigating mechanisms of PDE5-Is in disorders of UGTs are required.
Collapse
Affiliation(s)
- Wen-Hao Zhang
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan City 430071, Hubei Province, P.R. China
| | - Xin-Hua Zhang
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan City 430071, Hubei Province, P.R. China
| |
Collapse
|
14
|
Echeverri Tirado LC, Ferrer JE, Herrera AM. Aging and Erectile Dysfunction. Sex Med Rev 2016; 4:63-73. [DOI: 10.1016/j.sxmr.2015.10.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 06/22/2015] [Indexed: 01/23/2023]
|
15
|
Giagulli VA, Carbone MD, Ramunni MI, Licchelli B, De Pergola G, Sabbà C, Guastamacchia E, Triggiani V. Adding liraglutide to lifestyle changes, metformin and testosterone therapy boosts erectile function in diabetic obese men with overt hypogonadism. Andrology 2015; 3:1094-103. [DOI: 10.1111/andr.12099] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Revised: 07/18/2015] [Accepted: 07/29/2015] [Indexed: 01/01/2023]
Affiliation(s)
- V. A. Giagulli
- Outpatient Clinic for Endocrinology and Metabolic Diseases; Conversano Hospital; Conversano Italy
- Endocrinology and Metabolic Diseases; University of Bari; Bari Italy
| | - M. D. Carbone
- Institute of Clinical and Hormonal Research; Foggia Italy
| | - M. I. Ramunni
- Outpatient Clinic for Endocrinology and Metabolic Diseases; Conversano Hospital; Conversano Italy
| | - B. Licchelli
- Endocrinology and Metabolic Diseases; University of Bari; Bari Italy
| | - G. De Pergola
- Nutrition Outpatient Clinic; Clinical Oncology Unit; University of Bari; Bari Italy
| | - C. Sabbà
- Rare Diseases Center; University of Bari; Bari Italy
| | - E. Guastamacchia
- Endocrinology and Metabolic Diseases; University of Bari; Bari Italy
| | - V. Triggiani
- Endocrinology and Metabolic Diseases; University of Bari; Bari Italy
| |
Collapse
|
16
|
Toque HA, Caldwell RW. New approaches to the design and discovery of therapies to prevent erectile dysfunction. Expert Opin Drug Discov 2014; 9:1447-69. [DOI: 10.1517/17460441.2014.949234] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
17
|
Goswami SK, Inamdar MN, Jamwal R, Dethe S. Effect of Cinnamomum cassia methanol extract and sildenafil on arginase and sexual function of young male Wistar rats. J Sex Med 2014; 11:1475-83. [PMID: 24758372 DOI: 10.1111/jsm.12535] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Herbs have been used as an aphrodisiac since ages. Cinnamomum cassia is an important ingredient of many Ayurvedic formulations to treat male sexual disorder including erectile dysfunction (ED). AIM The objective of the present study was to evaluate erectogenic and aphrodisiac activity of methanol extract of C. cassia bark in young male rats. METHODS Methanol extract of C. cassia was screened in vitro for arginase inhibition potential and IC50 was determined. Effect of the extract was observed in vitro on phenylephrine pre-contracted isolated rat corpus cavernosum smooth muscle (CCSM) at 0.1, 1, 10, and 100 μg/mL. Young male Wistar rats were dosed with extract at 100 mg/kg body weight for 28 days and its effects on sexual behavior and penile smooth muscle : collagen level were observed. MAIN OUTCOME MEASURE Effect of C. cassia was studied on arginase activity in vitro and sexual behavior of young male rats. RESULTS C. cassia inhibited arginase activity in vitro with an IC50 of 61.72 ± 2.20 μg/mL. The extract relaxed phenylephrine pre-contracted isolated rat CCSM up to 43% and significantly increased (P < 0.05) sexual function of young male rats. Treatment with the extract also increased smooth muscle level and decreased collagen level in rat penile tissue. CONCLUSION The study proves usefulness of methanol extract of C. cassia bark for increasing sexual function.
Collapse
Affiliation(s)
- Sumanta K Goswami
- Department of Pharmacology, Al-Ameen College of Pharmacy, Bangalore, India
| | | | | | | |
Collapse
|
18
|
Goswami SK, Inamdar MN, Jamwal R, Dethe S. Efficacy of Cinnamomum cassia Blume. in age induced sexual dysfunction of rats. J Young Pharm 2013; 5:148-53. [PMID: 24563594 DOI: 10.1016/j.jyp.2013.11.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 11/01/2013] [Indexed: 01/23/2023] Open
Abstract
OBJECTIVE Cinnamomum cassia has been suggested in Ayurveda for the management of sexual dysfunction. This research work was conducted to shed some light on the mechanism of action of the extract, and evaluate the efficacy of its methanol extract in age induced sexual dysfunction in male Wistar rats. Secondary objective of the project was to study the effect of treatment on sperm parameters and smooth muscle:collagen level in rat penile tissue. METHODS Young and aged male rats were treated with methanol extract of Cinnamomum cassia at a dose of 100 mg/kg and sexual behavior was observed on 28th day in presence of female rats in estrous phase. Sildenafil was used as standard medicine. Effect of treatment was studied on epididymal sperm parameters, and Massons trichrome staining of rat penile tissues was performed to know the level of smooth muscle:collagen. RESULTS The treatment significantly increased sexual function in aged rats that had decreased in comparison to young rats, but did not have any significant effect on sperm count, live and defective sperm percentage. However, treatment induced an increase in smooth muscle level and a decrease in collagen level in the aged rat penile tissue in comparison to that of age matched control. CONCLUSION Based on our studies, we found that Cinnamomum cassia extract was effective in management of sexual dysfunction in aged rats and hence we propose a possible mechanism of action for Cinnamomum cassia which could be responsible for restoring sexual activity in aged rat.
Collapse
Affiliation(s)
| | | | - Rohitash Jamwal
- Bioassay Lab, Research and Development Centre, Natural Remedies Pvt. Ltd., Bangalore 560100, India
| | - Shekhar Dethe
- Bioassay Lab, Research and Development Centre, Natural Remedies Pvt. Ltd., Bangalore 560100, India
| |
Collapse
|
19
|
Mazur DJ, Helfand BT, McVary KT. Influences of Neuroregulatory Factors on the Development of Lower Urinary Tract Symptoms/Benign Prostatic Hyperplasia and Erectile Dysfunction in Aging Men. Urol Clin North Am 2012; 39:77-88. [DOI: 10.1016/j.ucl.2011.09.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
|
20
|
Zhang X, Zang N, Wei Y, Yin J, Teng R, Seftel A, Disanto ME. Testosterone regulates smooth muscle contractile pathways in the rat prostate: emphasis on PDE5 signaling. Am J Physiol Endocrinol Metab 2012; 302:E243-53. [PMID: 22028410 PMCID: PMC3340899 DOI: 10.1152/ajpendo.00458.2011] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Testosterone (T) plays a permissive role in the development of benign prostatic hyperplasia (BPH), and phosphodiesterase 5 inhibitors (PDE5is) have been found to be effective for BPH and lower urinary tract symptoms (LUTS) in clinical trials. This study investigated the effect of T on smooth muscle (SM) contractile and regulatory signaling pathways, including PDE5 expression and functional activity in prostate in male rats (sham-operated, surgically castrated, and castrated with T supplementation). In vitro organ bath studies, real-time RT-PCR, Western blot analysis, and immunohistochemistry were performed. Castration heavily attenuated contractility, including sensitivity to phenylephrine with SM myosin immunostaining revealing a disrupted SM cell arrangement in the stroma. PDE5 was immunolocalized exclusively in the prostate stroma, and orchiectomy signficantly reduced PDE5 immunopositivity, mRNA, and protein expression, along with nNOS and ROKβ mRNA, whereas it increased eNOS plus α(1a) and α(1b) adrenoreceptor expression in castrated animals. The PDE5i zaprinast significantly increased prostate strip relaxation to the nitric oxide donor sodium nitroprusside (SNP) in control but not castrated rats. But SNP alone was more effective on castrated rats, comparable with sham treated with SNP plus zaprinast. T supplementation prevented or restored all above changes, including SNP and zaprinast in vitro responsiveness. In conclusion, our data show that T positively regulates PDE5 expression and functional activities in prostate, and T ablation not only suppresses prostate size but also reduces prostatic SM contractility, with several potential SM contraction/relaxation pathways implicated. Zaprinast findings strongly suggest a major role for PDE5/cGMP in this signaling cascade. PDE5 inhibition may represent a novel mechanism for treatment of BPH.
Collapse
Affiliation(s)
- Xinhua Zhang
- Cooper University Hospital, Three Cooper Plaza, Camden, NJ 08103, USA
| | | | | | | | | | | | | |
Collapse
|
21
|
Gur S, Kadowitz PJ, Hellstrom WJ. RhoA/Rho‐Kinase as a Therapeutic Target for the Male Urogenital Tract. J Sex Med 2011; 8:675-87. [DOI: 10.1111/j.1743-6109.2010.02084.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
|
22
|
Zhang XH, Melman A, Disanto ME. Update on corpus cavernosum smooth muscle contractile pathways in erectile function: a role for testosterone? J Sex Med 2011; 8:1865-79. [PMID: 21324096 DOI: 10.1111/j.1743-6109.2011.02218.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Normal erectile function (EF) involves a coordinated relaxation of the arteries that supply the penis and the corpus cavernosum smooth muscle (CCSM), resulting in expansion of the sinusoids and increased intracavernous pressure. But the CCSM spends the majority of its time in the contracted state which is mediated by norepinephrine released from nerve endings and other vasoconstrictors like endothelins released from the endothelium. These agents cause smooth muscle myosin (SMM) phosphorylation by elevating intracellular calcium. When calcium returns to basal levels, the calcium sensitivity increases and prevents myosin dephosphorylation, which involves the RhoA/Rho-kinase (ROK) mechanism, thus maintaining force. Although mounting evidences demonstrate that androgens have a major influence on EF that is not just centrally mediated, this notion remains quite controversial. AIM To summarize the current knowledge on CCSM contractile pathways, the role they play in modulating EF, and the influence of androgens. METHODS The article reviews the literature and contains some previously unpublished data on CCSM contraction signaling including the role that androgens are known to play in modulating these pathways. MAIN OUTCOME MEASURES Data from peer-reviewed publications and previously unpublished observations. RESULTS In addition to downregulation of many pro-erectile molecular mechanisms, decreased testosterone (T) levels upregulate CCSM contractility, including hyperresponsiveness to α-adrenergic agonists, increased SMM phosphorylation, alteration of SMM isoform composition, activation of RhoA/ROK signaling and modulation of sphingosine-1-phosphate regulation of CCSM tone. CONCLUSIONS Decreased T levels upregulate CCSM contractile signaling. Meanwhile, it downregulates CCSM relaxation pathways synergizing to produce erectile dysfunction (ED). Although some urologists and researchers are still skeptical of the influence of androgens on penile erection, understanding these molecular control mechanisms as well as the influence that androgens have on these pathways should provide new evidence supporting the roles of androgens in EF and enhance the discovery of novel targets for drug development to treat ED.
Collapse
Affiliation(s)
- Xin-Hua Zhang
- Department of Surgery/Division of Urology, Cooper University Hospital, Camden, NJ, USA Department of Urology, First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | | | | |
Collapse
|
23
|
Nunes KP, Rigsby CS, Webb RC. RhoA/Rho-kinase and vascular diseases: what is the link? Cell Mol Life Sci 2010; 67:3823-36. [PMID: 20668910 PMCID: PMC2996825 DOI: 10.1007/s00018-010-0460-1] [Citation(s) in RCA: 117] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 07/07/2010] [Accepted: 07/08/2010] [Indexed: 12/29/2022]
Abstract
RhoA/Rho-kinase pathway plays an important role in many pathological conditions. RhoA participates in the regulation of smooth muscle tone and activates many downstream kinases. The best characterized are the serine/threonine kinase isoforms (Rho-kinase or ROCK), ROCKα/ROCK2 and ROCKβ/ROCK1. ROCK is necessary for diverse functions such as local blood flow, arterial/pulmonary blood pressure, airway resistance and intestinal peristalsis. ROCK activation permits actin/myosin interactions and smooth muscle cells contraction by maintaining the activity of myosin light-chain kinase, independently of the free cytosolic calcium level. The sensitization of smooth muscle myofilaments to calcium has been implicated in many pathological states, such as hypertension, diabetes, heart attack, stroke, pulmonary hypertension, erectile dysfunction, and cancer. The focus of this review is on the involvement of RhoA/Rho-kinase in diseases. We will briefly describe the ROCK isoforms and the role of RhoA/Rho-kinase in the vasculature, before exploring the most recent findings regarding this pathway and various diseases.
Collapse
Affiliation(s)
- Kenia Pedrosa Nunes
- Department of Physiology, Medical College of Georgia, Augusta, GA 30912, USA.
| | | | | |
Collapse
|
24
|
Chavalmane AK, Comeglio P, Morelli A, Filippi S, Fibbi B, Vignozzi L, Sarchielli E, Marchetta M, Failli P, Sandner P, Saad F, Gacci M, Vannelli GB, Maggi M. Sex Steroid Receptors in Male Human Bladder: Expression and Biological Function. J Sex Med 2010; 7:2698-713. [DOI: 10.1111/j.1743-6109.2010.01811.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
25
|
Hahmann C, Schroeter T. Rho-kinase inhibitors as therapeutics: from pan inhibition to isoform selectivity. Cell Mol Life Sci 2010; 67:171-7. [PMID: 19907920 PMCID: PMC11115778 DOI: 10.1007/s00018-009-0189-x] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 09/08/2009] [Accepted: 09/17/2009] [Indexed: 01/02/2023]
Abstract
The emerging critical implications of Rho/Rho-kinase (ROCK) signaling in neurodegenerative diseases, glaucoma, renoprotection, diabetes and cancer have sparked growing interest in the pharmacological potential of ROCK inhibitors beyond their current application in cardiovascular disease. This article discusses the therapeutic benefits of novel ROCK inhibitors in development, and highlights the recent advances in the current understanding of disease-dependent and isoform-specific functions of ROCK and their potential impact on future therapeutic strategies.
Collapse
Affiliation(s)
- C. Hahmann
- Discovery Biology, Translational Research Institute, The Scripps Research Institute, Scripps Florida, 130 Scripps Way, Jupiter, FL 33458 USA
| | - T. Schroeter
- Discovery Biology, Translational Research Institute, The Scripps Research Institute, Scripps Florida, 130 Scripps Way, Jupiter, FL 33458 USA
| |
Collapse
|
26
|
Abstract
Erectile dysfunction (ED) is a clinical disorder that results from a continuous spectrum of clinical factors, including physical illness (comprising the organic component of ED), reaction to stress (the intrapsychic component of ED) and relationship difficulties (the relationship component of ED). Testosterone clearly has a relevant role in all three causes of ED; the usefulness of this hormone in the treatment of ED has not, however, been completely clarified. The main physiological action of testosterone in the male sexual response is to regulate the timing of the erectile process as a function of sexual desire, thereby coordinating penile erection with sex. The link between ED, hypogonadism and underlying disorders (such as metabolic syndrome and type 2 diabetes mellitus) is nowadays well documented. The recognition of underlying disorders might be useful in motivating men with ED to improve their health-related lifestyle choices. Hence, patients with ED might be considered 'lucky', because their disorder offers the opportunity to undergo medical examinations to detect underlying disease. Both ED and hypogonadism are treatable conditions. A range of testosterone preparations are available for supplementation; their combination with phosphodiesterase 5 inhibitors might improve outcomes in some cases.
Collapse
|
27
|
Wingard CJ, Moukdar F, Prasad RY, Cathey BL, Wilkinson L. Reversal of voltage-dependent erectile responses in the Zucker obese-diabetic rat by rosuvastatin-altered RhoA/Rho-kinase signaling. J Sex Med 2009; 6 Suppl 3:269-78. [PMID: 19267849 DOI: 10.1111/j.1743-6109.2008.01184.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
INTRODUCTION The combination of independent risk factors for erectile dysfunction, obesity, hypertension, and diabetes are collectively manifested in a condition known as metabolic syndrome X (MSX). However, the regulatory mechanisms responsible for the erectile dysfunction (ED) are not fully understood. Clinical studies suggest that a pleiotropic effect of statin's ability to enhance vascular relaxation might be through an impact on nitric oxide signaling or through a regulation of RhoA activation. AIM We hypothesized that regulatory aspects of short-term statin therapy involve the alteration of the RhoA/Rho-kinase signaling cascade and will reverse the ED seen in a rat model of MSX. MAIN OUTCOME MEASURES The magnitude and sensitivity of the voltage-dependent maintenance of intracavernosal blood pressure and mean arterial blood pressure. These responses were correlated with tissue protein and mRNA expression levels of RhoA and Rho kinases. METHODS Erectile function was evaluated by assessing voltage-dependent stimulation of the cavernosal nerve in 16-20 weeks old lean and obese-diabetic Zucker rats treated with 5 mg/kg/day of rosuvastatin intraperitoneally for 3 days. Cavernosal tissue RhoA and Rho-kinases expression levels were evaluated by real-time reverse transcriptase-polymerase chain reaction, Western blot. RESULTS The voltage-dependent erectile responses were suppressed by >30% in the obese-diabetic Zucker rat. The 3-day treatment with rosuvastatin partially restored the erectile response. The Rho-kinase inhibitor, H-1152, dose dependently increased the erectile responses and shifted the voltage sensitivity with statin treatment. Analysis of protein expression levels suggested elevation of RhoA and Rho kinases in obese-diabetics and statin treatment lowering Rho-kinase II. The RhoA and Rho-kinase II mRNA levels were significantly reduced in the rosuvastatin-treated obese-diabetic animals. CONCLUSIONS These results support a hypothesis that short-term statin therapy may lower RhoA/Rho-kinase expression levels and improve cavernosal blood pressure response to Rho-kinase inhibition and voltage-stimulation, and reversing an augmented vasoconstricted state associated with diabetes and/or hypertension in MSX.
Collapse
Affiliation(s)
- Christopher J Wingard
- Brody School of Medicine at East Carolina University, Department of Physiology, Greenville, NC 27834, USA.
| | | | | | | | | |
Collapse
|
28
|
Lin CS, Xin ZC, Wang Z, Lin G, Lue TF. Molecular Yin and Yang of erectile function and dysfunction. Asian J Androl 2008; 10:433-40. [PMID: 18385905 DOI: 10.1111/j.1745-7262.2008.00396.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
In regard to erectile function, Yin is flaccidity and Yang erection. In the past decade, research has mostly focused on the Yang aspect of erectile function. However, in recent years, the Yin side is attracting increasingly greater attention. This is due to the realization that penile flaccidity is no less important than penile erection and is actively maintained by mechanisms that play critical roles in certain types of erectile dysfunction (ED); for example, in diabetic patients. In addition, there is evidence that the Yin and Yang signaling pathways interact with each other during the transition from flaccidity to erection, and vice versa. As such, it is important that we view erectile function from not only the Yang but also the Yin side. The purpose of this article is to review recent advances in the understanding of the molecular mechanisms that regulate the Yin and Yang of the penis. Emphasis is given to the Rho kinase signaling pathway that regulates the Yin, and to the cyclic nucleotide signaling pathway that regulates the Yang. Discussion is organized in such a way so as to follow the signaling cascade, that is, beginning with the extracellular signaling molecules (e.g., norepinephrin and nitric oxide) and their receptors, converging onto the intracellular effectors (e.g., Rho kinase and protein kinase G), branching into secondary effectors, and finishing with contractile molecules and phosphodiesterases. Interactions between the Yin and Yang signaling pathways are discussed as well.
Collapse
Affiliation(s)
- Ching-Shwun Lin
- Knuppe Molecular Urology Laboratory, University of California, San Francisco, CA 94143, USA.
| | | | | | | | | |
Collapse
|
29
|
Yuan J, DeSouza R, Westney OL, Wang R. Insights of priapism mechanism and rationale treatment for recurrent priapism. Asian J Androl 2008; 10:88-101. [DOI: 10.1111/j.1745-7262.2008.00314.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
|
30
|
Vignozzi L, Morelli A, Filippi S, Ambrosini S, Mancina R, Luconi M, Mungai S, Vannelli GB, Zhang XH, Forti G, Maggi M. Testosterone Regulates RhoA/Rho-Kinase Signaling in Two Distinct Animal Models of Chemical Diabetes. J Sex Med 2007; 4:620-632. [PMID: 17498101 DOI: 10.1111/j.1743-6109.2007.00440.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
INTRODUCTION The contractile RhoA/Rho-kinase (ROCK) signaling pathway is upregulated in penile tissue in animal models of experimental diabetes and has been proposed to contribute to diabetes-related erectile dysfunction (ED). AIM To investigate the effect of testosterone (T) on the RhoA/ROCK signaling in diabetes. METHODS We used two distinct animal models of chemical diabetes (alloxan-induced in the rabbit and streptozotocin-induced in the rat) with or not T supplementation. MAIN OUTCOME MEASURES The effect of diabetes and T supplementation on RhoA/ROCK signaling was evaluated as responsiveness to the selective ROCK inhibitor Y-27632 either by "in vitro" contractility study (diabetic rabbit) or "in vivo" as erectile response elicited by intracavernous injections (diabetic rats). RhoA/ROCK gene and protein expression were also analyzed. RESULTS In both models, hypogonadism was observed, characterized by reduced T plasma level and androgen-dependent accessory glands atrophy. Diabetic animals showed a significant increase in responsiveness to increasing concentrations of Y-27632. T substitution (30 mg/kg, weekly) completely prevented hypogonadism and diabetes-induced penile hypersensitivity to Y-27632. To test whether this effect was due to a T-dependent regulation of RhoA/ROCK gene expression, we measured RhoA/ROCK mRNA. Both isoforms of ROCK (ROCK1/ROCK2) were analyzed by real-time reverse transcriptase polymerase chain reaction (RT-PCR) in rat penile samples. We found that ROCK1 mRNA was significantly increased (P < 0.05) in penile tissues from diabetic animals and maintained at the control values by T, as also confirmed by semiquantitative RT-PCR in rabbit. Conversely, RhoA and ROCK2 mRNA expression was not influenced either by diabetic condition or by T administration. Accordingly, ROCK1 protein expression, as evaluated by Western blot and immunohistochemistry analysis, was increased in penile samples from diabetic animals and normalized by T. CONCLUSIONS Our data further support the hypothesis that the overexpression of RhoA/ROCK signaling contributes to diabetes-related ED. Moreover, treating hypogonadism in course of diabetes may maintain erectile function also by normalizing RhoA/ROCK pathway upregulation.
Collapse
Affiliation(s)
| | | | - Sandra Filippi
- Interdep. Laboratory of Functional and Cellular Pharmacology of Reproduction, Departments of Pharmacology and Clinical Physiopathology, University of Florence, Florence, Italy
| | - Stefano Ambrosini
- Department of Anatomy, Histology and Forensic Medicine, University of Florence, Florence, Italy
| | | | - Michaela Luconi
- Endocrinology Unit, Department of Clinical Physiopathology, Center for Research, Transfer and High Education DENOTHE, University of Florence, Florence, Italy
| | | | | | | | - Gianni Forti
- Endocrinology Unit, Department of Clinical Physiopathology, Center for Research, Transfer and High Education DENOTHE, University of Florence, Florence, Italy
| | | |
Collapse
|
31
|
Iwakubo M, Takami A, Okada Y, Kawata T, Tagami Y, Sato M, Sugiyama T, Fukushima K, Taya S, Amano M, Kaibuchi K, Iijima H. Design and synthesis of rho kinase inhibitors (III). Bioorg Med Chem 2007; 15:1022-33. [PMID: 17084087 DOI: 10.1016/j.bmc.2006.10.028] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2006] [Revised: 10/12/2006] [Accepted: 10/14/2006] [Indexed: 10/24/2022]
Abstract
The structure-activity relationship of Rho kinase inhibitors bearing an isoquinoline scaffold was studied. N-(1-Benzyl-3-pyrrolidyl)-N-(5-isoquinolyl)amine analogues were optimized with respect to their inhibitory potencies for the enzyme and for chemotaxis. The potent analogues were further evaluated by an ex vivo test in which the selected compounds were orally administered to rats, and the Rho kinase inhibitory potency observed in the rat serum was evaluated 3h after the administration. Compound 23g showed a high level of Rho kinase inhibitory activity in the rat serum and was stable in an in vitro metabolic test using a microsomal cytochrome preparation. The (R)-isomer of 23g displayed a higher level of inhibitory potency than the (S)-isomer in a cell-free kinase assay and in the cell migration assay (IC(50)(ENZ)=25 nM and IC(50)(MCP)=1 microM). The (R)-isomer successfully inhibited the phosphorylation of MBS (myosin-binding subunit) in cells.
Collapse
Affiliation(s)
- Masayuki Iwakubo
- Pharmaceutical Research Laboratories, Kirin Brewery Co. Ltd., 3 Miyahara-cho, Takasaki-shi, Gunma 370-1295, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Bivalacqua TJ, Liu T, Musicki B, Champion HC, Burnett AL. Endothelial nitric oxide synthase keeps erection regulatory function balance in the penis. Eur Urol 2006; 51:1732-40. [PMID: 17113219 PMCID: PMC3328507 DOI: 10.1016/j.eururo.2006.10.061] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Accepted: 10/23/2006] [Indexed: 11/28/2022]
Abstract
OBJECTIVES We evaluated the regulatory influence of endothelial nitric oxide (NO) on the basal functional states of the NO and RhoA/Rho-kinase signaling pathways in the penis using endothelial NO synthase (eNOS) mutant mice and eNOS gene transfer technology. METHODS Four groups of mice were used: wild type (WT), eNOS gene deleted (eNOS-/-), eNOS and neuronal NOS gene deleted (dNOS-/-), and eNOS-/- mutant mice transfected intracavernosally with eNOS. Cyclic guanosine monophosphate (cGMP) concentration, protein kinase G (PKG) activity, activated RhoA, and Rho-kinase activity were determined in penes of WT and both mutant mouse groups. Constitutive NOS and PKG activities, RhoA, Rho-kinase-alpha and -beta isoforms, and phosphorylated myosin light-chain phosphatase target subunit (p-MYPT-1) expressions and Rho-kinase activity were determined in penes of eNOS-/- mice after eNOS gene transfer. RESULTS Compared with results in the WT penis, eNOS-/- and dNOS-/- mutant mouse penes had significant reductions in NOS activity, cGMP concentration, PKG activity, Rho-kinase activity, and p-MYPT-1 expression (p<0.05) with no significant changes in activated RhoA or in RhoA and Rho-kinase-alpha and -beta protein expressions. After eNOS gene transfer to penes of eNOS-/- mice, Rho-kinase-beta and p-MYPT-1 expressions and total Rho-kinase activity were significantly increased from baseline levels (p<0.05). CONCLUSIONS These data suggest that endothelial NO has a role in the penis as a regulator of the basal signaling functions of the NO and RhoA/Rho-kinase erection mediatory pathways. These data offer new insight into the homeostasis of erection regulatory biology.
Collapse
Affiliation(s)
- Trinity J. Bivalacqua
- The James Buchanan Brady Urological Institute, Department of Urology, Johns Hopkins Hospital, Baltimore, MD
| | - Tongyun Liu
- The James Buchanan Brady Urological Institute, Department of Urology, Johns Hopkins Hospital, Baltimore, MD
| | - Biljana Musicki
- The James Buchanan Brady Urological Institute, Department of Urology, Johns Hopkins Hospital, Baltimore, MD
| | - Hunter C. Champion
- Division of Cardiology, Department of Medicine, Johns Hopkins Hospital, Baltimore, MD
| | - Arthur L. Burnett
- The James Buchanan Brady Urological Institute, Department of Urology, Johns Hopkins Hospital, Baltimore, MD
| |
Collapse
|
33
|
Pathways to relaxation of corporal smooth muscle. CURRENT SEXUAL HEALTH REPORTS 2006. [DOI: 10.1007/s11930-006-0013-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
34
|
Jin L, Burnett AL. RhoA/Rho-kinase in erectile tissue: mechanisms of disease and therapeutic insights. Clin Sci (Lond) 2006; 110:153-65. [PMID: 16411892 DOI: 10.1042/cs20050255] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Penile erection is a complicated event involving the regulation of corpus cavernosal smooth muscle tone. Recently, the small monomeric G-protein RhoA and its downstream effector Rho-kinase have been proposed to be important players for mediating vasoconstriction in the penis. RhoA/Rho-kinase increases MLC (myosin light chain) phosphorylation through inhibition of MLCP (MLC phosphatase) thereby increasing Ca2+ sensitivity. This review will outline the RhoA/Rho-kinase signalling pathway, including the upstream regulators, guanine nucleotide exchange factors, GDP dissociation inhibitors and GTPase-activating proteins. We also summarize the current knowledge about the physiological roles of RhoA/Rho-kinase in both male and female erectile tissues and its aberrations contributing to erectile dysfunction in several disease states. Understanding the RhoA/Rho-kinase signalling pathway in the regulation of erection is important for the development of therapeutic interventions for erectile dysfunction.
Collapse
Affiliation(s)
- Liming Jin
- Department of Urology, Johns Hopkins University, Baltimore, MD 21287, USA.
| | | |
Collapse
|
35
|
Rajasekaran M, White S, Baquir A, Wilkes N. Rho-kinase inhibition improves erectile function in aging male Brown-Norway rats. ACTA ACUST UNITED AC 2005; 26:182-8. [PMID: 15713824 DOI: 10.1002/j.1939-4640.2005.tb01084.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Physiological aging is a significant risk factor in the on-set of male erectile dysfunction (ED) and an imbalance in factors that modulate cavernosal smooth-muscle tone may play a role in these altered penile hemodynamic mechanisms. To evaluate the association between aging and male erectile function, we monitored neurogenic erectile response and its correlation to systemic arterial pressure changes in old (21-23 months of age) vs young (6-9 months of age) Brown-Norway (BN) rats. We tested the hypothesis that age-associated ED is due to unregulated vasoconstrictive tone, contributed in part by an increased Rho-kinase activity, and that antagonism of Rho-kinase activity attenuates the age-related decline in male erectile function. We also examined the hypothesis that a combination of Rho-kinase antagonism and phosphodiesterase-5 (PDE-5) inhibition has a synergistic effect in improving the erectile response in these aging animals. Erectile function in old BN rats was evaluated before and after intracavernosal injection of a specific inhibitor of Rho-kinase (Y-27632) alone or in combination with zaprinast, a PDE-5 inhibitor. Erectile capabilities of the young and old BN rat groups were significantly different in corpus cavernosum pressure response after electrical-field stimulation of the major pelvic ganglion. Y-27632 administration attenuated the aging-related changes in male erectile function seen in BN rats. Rho-kinase antagonism and PDE-5 inhibition had a synergistic effect in improving erectile function in old rats. Our data indicate that aging leads to impairment in the neurogenic erectile response in BN rats involving a possible derangement in penile hemodynamic mechanisms of the erectile tissue. Rho-kinase inhibition may be of value in treating age-related ED.
Collapse
Affiliation(s)
- Mahadevan Rajasekaran
- Division of Urology, University of California San Diego Medical Center, 200 West Arbor Dr (8897), San Diego, CA 92103-8897, USA.
| | | | | | | |
Collapse
|
36
|
Abstract
Rho-kinase is a signaling molecule that occurs downstream of the small GTPase Rho, which mediates various cellular functions. The Rho/Rho-kinase pathway plays an important role in pathophysiology and progression of various cardiovascular diseases such as hypertension, coronary vasospasm, angina pectoris, and restenosis after percutaneous coronary intervention, all of which are related to arteriosclerosis/atherosclerosis changes of the vasculature. Activation of the Rho/Rho-kinase pathway contributes to inflammatory and proliferative changes of the blood vessels and affects cardiac myocytes. Evidence from in vitro and in vivo studies suggests that Rho-kinase inhibitors have beneficial effects on cardiovascular diseases, particularly arteriosclerosis and coronary vasospasm. Furthermore, activation of the Rho/Rho-kinase pathway contributes to blood pressure regulation via the central sympathetic nervous system. There is evidence to suggest that Rho-kinase is involved in angiotensin II-induced cardiac hypertrophy and endothelial dysfunction, and preliminary data indicate that inhibition of Rho-kinase may be beneficial in vascular disorders such as pulmonary arterial hypertension and erectile dysfunction. Fasudil is currently the only Rho-kinase inhibitor available for clinical use and it is approved in Japan for the prevention of vasospasm in patients with subarachnoid hemorrhage. Emerging clinical data have shown that oral fasudil 80 mg three times daily is effective in preventing myocardial ischemia in patients with stable angina pectoris. Rho-kinase represents a new target for the management of cardiovascular diseases and further studies are needed to define the therapeutic potential of Rho-kinase inhibitors.
Collapse
Affiliation(s)
- Yoshitaka Hirooka
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Kyushu University, Fukuoka, Kyushu, Japan.
| | | |
Collapse
|
37
|
Brown JS, Wessells H, Chancellor MB, Howards SS, Stamm WE, Stapleton AE, Steers WD, Van Den Eeden SK, McVary KT. Urologic complications of diabetes. Diabetes Care 2005; 28:177-85. [PMID: 15616253 DOI: 10.2337/diacare.28.1.177] [Citation(s) in RCA: 192] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Jeanette S Brown
- University of California, San Francisco, San Francisco, California 94115, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Husain S, Young D, Wingard CJ. Role of PKCα and PKCι in phenylephrine-induced contraction of rat corpora cavernosa. Int J Impot Res 2003; 16:325-33. [PMID: 14961054 DOI: 10.1038/sj.ijir.3901164] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Constriction of the penile vasculature prevents erection and is largely mediated by physiological agonists. We hypothesized that protein kinase C (PKC) may act as a regulator of penile vascular tone. Studies were designed to identify PKC isoforms present and to investigate their roles in phenylephrine-induced muscle contraction in the isolated rat corpora cavernosa. We demonstrated the presence of PKCalpha, beta, gamma, epsilon, delta, eta, and iota in rat corpora cavernosa and a subcellular distribution, which favored a membrane association for PKCalpha, beta, delta, and iota. Phenylephrine (3 microM) generated an active stress of 9.6 +/- 1.5 mN/mm2 and was associated with a significant increase of PKCalpha and PKCiota immunoreactivity in the particulate fraction. The amount of PKCalpha and PKCiota in the particulate fraction rose by 36 +/- 4.4 and 51 +/- 2.2% with phenylephrine stimulation. Furthermore, the phenylephrine concentration-response curve was potentiated in the presence of phorbol 12-myristate13-acetate (PMA) (0.1 microM), a PKC activator (EC50: phenylephrine 1.0 +/- 0.8 microM vs phenylephrine + PMA 0.3 +/- 0.1 microM) and inhibited in the presence of chelerythrine chloride (30 microM), a PKC inhibitor (EC50: phenylephrine 1.0 +/- 0.8 microM vs phenylephrine + chelerythrine chloride 5.7 +/- 2.4 microM). Based on these results, we suggest a potential role for PKCalpha and PKCiota in phenylephrine-induced smooth muscle tone of the rat cavernosum.
Collapse
Affiliation(s)
- S Husain
- Department of Biochemistry and Molecular Biology, Medical College of Georgia, Augusta, Georgia 30912, USA
| | | | | |
Collapse
|
39
|
Wingard CJ, Husain S, Williams J, James S. RhoA-Rho kinase mediates synergistic ET-1 and phenylephrine contraction of rat corpus cavernosum. Am J Physiol Regul Integr Comp Physiol 2003; 285:R1145-52. [PMID: 12893655 DOI: 10.1152/ajpregu.00329.2003] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Maintenance of the detumescent state of the penis is believed to involve the actions of several vasoconstrictors. However, our mechanistic understanding of any synergistic vasoconstrictor influences is extremely limited. We tested the hypothesis that a vasoconstrictor combination of endothelin (ET-1) and phenylephrine (PE) augments the constrictor responses in rat corporal cavernosal tissues by a mechanism involving the RhoA-Rho kinase pathway. Independently, ET-1 (1 nM-30 microM) and PE (100 nM-100 microM) both caused dose-dependent contractions of isolated rat cavernosal tissues. In combination, ET-1 (30 nM) augmented the contractile effect of PE and shifted the calculated EC50 for PE (90 +/- 12 to 45 +/- 5 microM). The active stress generated by cavernosal strips during the ET-1 + PE combined stimulation (4.9 +/- 0.2 mN/mm2) was greater than the combined stress generated with ET-1 (0.4 +/- 0.1 mN/mm2) or PE (3.3 +/- 0.2 mN/mm2) stimulations alone. Blockade of ETA receptors (30 nM; A-127722) reversed the augmented stress generation and the Rho-kinase inhibitor Y-27632 differentially and dose-dependently relaxed the tissue. The combined constrictor effect was associated with a fourfold increase of RhoA in the membrane faction of the tissue homogenates. We conclude that the ET-1 + PE combination potentiate vasoconstriction through mutual activation of the RhoA-Rho kinase pathway. The interactions of these agonists likely play important roles in the maintenance of the flaccid state and contribute to some forms of erectile dysfunction.
Collapse
Affiliation(s)
- Christopher J Wingard
- Dept. of Physiology, Medical College of Georgia, 1120 15th St., Augusta GA, 30912, USA.
| | | | | | | |
Collapse
|