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Cho KJ, Hashimoto M, Karnup S, Matsuoka K, Kamijo T, Kim JC, Koh JS, Yoshimura N. Improvement of lower urinary tract dysfunction by a monoacylglycerol lipase inhibitor in mice with spinal cord injury. Neurourol Urodyn 2024; 43:1207-1216. [PMID: 38533637 DOI: 10.1002/nau.25458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 03/06/2024] [Accepted: 03/15/2024] [Indexed: 03/28/2024]
Abstract
AIMS Activation of the endocannabinoid system by monoacylglycerol lipase (MAGL) blockade may affect the lower urinary tract function. We investigated the effect of an MAGL inhibitor, MJN110, on neurogenic lower urinary tract dysfunction (LUTD) in the mouse model of spinal cord injury (SCI). METHODS Female C57BL/6 mice that underwent spinal cord transection at T8-10 level were divided into three groups consisting of (1) vehicle-treated SCI mice, (2) 5 mg/kg, or (3) 10 mg/kg of MJN110-treated SCI mice. MJN110 and vehicle were administered intraperitoneally for 7 days from 4 weeks after spinal cord transection. We then conducted awake cystometrograms and compared urodynamic parameters between three groups. The expression of cannabinoid (CB) receptors, TRP receptors, and inflammatory cytokines in L6-S1 dorsal root ganglia (DRG) or the bladder mucosa were evaluated and compared among three groups. Changes in the level of serum 2-arachidonoylglycerol (2-AG) and bladder MAGL were also evaluated. RESULTS In the cystometrogram, detrusor overactivity (DO) parameters, such as the number of nonvoiding contraction (NVC), a ratio of time to the 1st NVC to intercontraction interval (ICI), and NVC integrals were improved by MJN110 treatment, and some effects were dose dependent. Although MJN110 did not improve voiding efficiency, it decreased bladder capacity, ICI, and residual urine volume compared to vehicle injection. MJN110 treatment groups had lower CB2, TRPV1, TRPA1, and inflammatory cytokines mRNA levels in DRG and bladder mucosa. Serum 2-AG was increased, and bladder MAGL was decreased after MAGL inhibitor treatment. CONCLUSIONS MAGL inhibition improved LUTD including attenuation of DO after SCI. Thus, MAGL can be a therapeutic target for neurogenic LUTD after SCI.
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MESH Headings
- Animals
- Monoacylglycerol Lipases/antagonists & inhibitors
- Monoacylglycerol Lipases/metabolism
- Spinal Cord Injuries/physiopathology
- Spinal Cord Injuries/drug therapy
- Spinal Cord Injuries/complications
- Spinal Cord Injuries/metabolism
- Female
- Mice, Inbred C57BL
- Urinary Bladder/drug effects
- Urinary Bladder/physiopathology
- Urodynamics/drug effects
- Mice
- Disease Models, Animal
- Ganglia, Spinal/drug effects
- Ganglia, Spinal/metabolism
- Ganglia, Spinal/physiopathology
- Receptors, Cannabinoid/metabolism
- Receptors, Cannabinoid/drug effects
- Enzyme Inhibitors/pharmacology
- Endocannabinoids/metabolism
- Cytokines/metabolism
- Urinary Bladder, Neurogenic/drug therapy
- Urinary Bladder, Neurogenic/physiopathology
- Urinary Bladder, Neurogenic/etiology
- Lower Urinary Tract Symptoms/drug therapy
- Lower Urinary Tract Symptoms/physiopathology
- Lower Urinary Tract Symptoms/etiology
- Carbamates
- Succinimides
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Affiliation(s)
- Kang Jun Cho
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Urology, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Mamoru Hashimoto
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Urology, Kindai University Faculty of Medicine, Osaka-Sayama, Japan
| | - Sergei Karnup
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Kanako Matsuoka
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Tadanobu Kamijo
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Joon Chul Kim
- Department of Urology, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jun Sung Koh
- Department of Urology, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Naoki Yoshimura
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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Cho KJ, Kim JC. Novel pharmacotherapeutic avenues for bladder storage dysfunction in men. Expert Opin Pharmacother 2024; 25:585-594. [PMID: 38651268 DOI: 10.1080/14656566.2024.2346278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 04/18/2024] [Indexed: 04/25/2024]
Abstract
INTRODUCTION Bladder storage dysfunction is associated with low quality of life in men and remains a challenging field in pharmacotherapy because of low persistence followed by patient-perceived lack of efficacy and adverse effects. The persistent desire for the development of novel pharmacotherapy is evident, leading to numerous research efforts based on its pathophysiology. AREAS COVERED This review describes the pathophysiology, current pharmacotherapeutic strategies, and emerging novel drugs for male bladder storage dysfunction. The section on emerging pharmacotherapy provides an overview of current research, focusing on high-potential target molecules, particularly those being evaluated in ongoing clinical trials. EXPERT OPINION As pharmacotherapies targeting alpha-adrenergic, beta-adrenergic, and muscarinic receptors - the current primary targets for treating male bladder storage dysfunction - have demonstrated insufficient efficacy and side effects, researchers are exploring various alternative molecular targets. Numerous targets have been identified as central to regulating bladder afferent nerve activity, and their pharmacological effects and potential have been evaluated in animal-based experiments. However, there is a limited number of clinical trials for these new pharmacotherapies, and they have not demonstrated clear superiority over current treatments. Further research is needed to develop new effective pharmacotherapies for bladder storage dysfunction in men.
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Affiliation(s)
- Kang Jun Cho
- Department of Urology, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Joon Chul Kim
- Department of Urology, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
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Torimoto K, Ueda T, Gotoh D, Kano K, Miyake M, Nakai Y, Hori S, Morizawa Y, Onishi K, Shimizu T, Tomizawa M, Aoki J, Fujimoto K. Serum anandamide and lipids associated with linoleic acid can distinguish interstitial cystitis/bladder pain syndrome from overactive bladder: An exploratory study. Low Urin Tract Symptoms 2023; 15:238-246. [PMID: 37688290 DOI: 10.1111/luts.12501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 08/23/2023] [Accepted: 08/29/2023] [Indexed: 09/10/2023]
Abstract
OBJECTIVES Diagnosing interstitial cystitis/bladder pain syndrome presents a major challenge because it relies on subjective symptoms and empirical cystoscopic findings. A practical biomarker should discriminate diseases that cause increased urinary frequency, particularly overactive bladder. Therefore, we aimed to identify blood biomarkers that can discriminate between interstitial cystitis/bladder pain syndrome and overactive bladder. METHODS We enrolled patients with Hunner-type interstitial cystitis (n = 20), bladder pain syndrome (n = 20), and overactive bladder (n = 20) and without lower urinary tract symptoms (controls, n = 15) at Ueda Clinic and Nara Medical University Hospital from February 2020 to August 2021. The degree of interstitial cystitis/bladder pain syndrome symptoms was evaluated using the interstitial cystitis symptom and problem indices. Metabolomics analysis was performed on 323 serum metabolites using liquid chromatography time-of-flight mass spectrometry. RESULTS In the Hunner-type interstitial cystitis or bladder pain syndrome group, we observed smaller relative areas, including anandamide, acylcarnitine (18:2), linoleoyl ethanolamide, and arachidonic acid, compared to those in the overactive bladder or control group. Notably, the differences in the relative areas of anandamide were statistically significant (median: 3.950e-005 and 4.150e-005 vs. 8.300e-005 and 9.800e-005), with an area under the curve of 0.9321, demonstrating its ability to discriminate interstitial cystitis/bladder pain syndrome. CONCLUSIONS Serum anandamide may be a feasible diagnostic biomarker for interstitial cystitis/bladder pain syndrome. Reduced serum anandamide levels may be associated with pain and inflammation initiation, reflecting the pathology of interstitial cystitis/bladder pain syndrome. Furthermore, our findings suggest that abnormal linoleic acid metabolism may be involved in the pathogenesis of interstitial cystitis/bladder pain syndrome.
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Affiliation(s)
| | | | - Daisuke Gotoh
- Department of Urology, Nara Medical University, Nara, Japan
| | - Kuniyuki Kano
- Department of Health Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Tokyo, Japan
| | - Makito Miyake
- Department of Urology, Nara Medical University, Nara, Japan
| | - Yasushi Nakai
- Department of Urology, Nara Medical University, Nara, Japan
| | - Shunta Hori
- Department of Urology, Nara Medical University, Nara, Japan
| | | | - Kenta Onishi
- Department of Urology, Nara Medical University, Nara, Japan
| | - Takuto Shimizu
- Department of Urology, Nara Medical University, Nara, Japan
| | | | - Junken Aoki
- Department of Health Chemistry, Graduate School of Pharmaceutical Science, The University of Tokyo, Tokyo, Japan
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Ramsay S, Spencer NJ, Zagorodnyuk V. Endocannabinoids, anandamide and 2-AG, regulate mechanosensitivity of mucosal afferents in the Guinea pig bladder. Eur J Pharmacol 2023; 945:175624. [PMID: 36858341 DOI: 10.1016/j.ejphar.2023.175624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 02/01/2023] [Accepted: 02/23/2023] [Indexed: 03/02/2023]
Abstract
Bladder afferents play a crucial role in urine storage and voiding, and conscious sensations from the bladder. Endocannabinoids, anandamide (AEA) and 2-arachidonolylglycerol (2-AG), are endogenous ligands of G-protein coupled cannabinoid receptors 1 and 2 (CB1 and CB2) found in the CNS and peripheral organs. They also have off-target effects on some ligand- and voltage-gated channels. The aim of this study is to determine the role of AEA and 2-AG in regulation of mechanosensitivity of probable nociceptive neurons innervating the bladder - capsaicin-sensitive mucosal afferents. The activity of these afferents was determined by ex vivo single unit extracellular recordings in the guinea pig bladder. A stable analogue of anandamide, methanandamide (mAEA) evoked initial excitatory response of mucosal afferents followed by potentiation of their responses to mechanical stimulation. In the presence of TRPV1 antagonist (AMG9810), mAEA's effect on mechanosensitivity switched from excitatory to inhibitory. The inhibitory effect of mAEA is due to activation of both CB1 and CB2 cannabinoid receptors since it was abolished by combined application of selective CB1 (NESS0327) and CB2 (SR144528) antagonists. 2-AG application evoked a brief excitation of mucosal afferents, without potentiation of their mechanosensitivity, followed by the inhibition of their responses to mechanical stimulation. CB2 receptor antagonist, SR144528 abolished the inhibitory effect of 2-AG. Our data indicated that anandamide and 2-AG have opposite effects on mechanosensitivity of mucosal capsaicin-sensitive afferents in the guinea pig bladder; mAEA potentiated while 2-AG inhibited responses of mucosal afferents to mechanical stimulation. These findings are important for understanding of the role of endocannabinoids in regulating bladder sensation and function.
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Affiliation(s)
- Stewart Ramsay
- Discipline of Human Physiology, Flinders Health & Medical Research Institute, College of Medicine and Public Health, Flinders University, South Australia, Australia
| | - Nick J Spencer
- Discipline of Human Physiology, Flinders Health & Medical Research Institute, College of Medicine and Public Health, Flinders University, South Australia, Australia
| | - Vladimir Zagorodnyuk
- Discipline of Human Physiology, Flinders Health & Medical Research Institute, College of Medicine and Public Health, Flinders University, South Australia, Australia.
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Golosova D, Levchenko V, Kravtsova O, Palygin O, Staruschenko A. Acute and long-term effects of cannabinoids on hypertension and kidney injury. Sci Rep 2022; 12:6080. [PMID: 35413977 PMCID: PMC9005691 DOI: 10.1038/s41598-022-09902-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 03/28/2022] [Indexed: 11/30/2022] Open
Abstract
Cannabinoids and their endogenous and synthetic analogs impact blood pressure and contribute to the incidence of hypertension. It was previously reported that the endocannabinoid system plays an important role in developing hypertension; however, it was also shown that cannabinoids elicit profound hypotension associated with hemorrhagic, cardiogenic, and endotoxic shock. This study aimed to test acute and chronic effects of an endogenous ligand of cannabinoid receptor anandamide (AEA) on blood pressure and kidney injury in vivo in conscious Dahl salt-sensitive (SS) rats. We demonstrated that acute i.v. bolus administration of a low or a high doses (0.05 or 3 mg/kg) of AEA did not affect blood pressure for 2 h after the injection in Dahl SS rats fed a normal salt diet (0.4% NaCl). Neither low nor high doses of AEA had any beneficial effects on blood pressure or kidney function. Furthermore, hypertensive rats fed a HS diet (8% NaCl) and chronically treated with 3 mg/kg of AEA exhibited a significant increase in blood pressure accompanied by increased renal interstitial fibrosis and glomerular damage at the late stage of hypertension. Western blot analyses revealed increased expression of Smad3 protein levels in the kidney cortex in response to chronic treatment with a high AEA dose. Therefore, TGF-β1/Smad3 signaling pathway may play a crucial role in kidney injury in SS hypertension during chronic treatment with AEA. Collectively, these data indicate that prolonged stimulation of cannabinoid receptors may result in aggravation of hypertension and kidney damage.
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Affiliation(s)
- Daria Golosova
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA.
| | - Vladislav Levchenko
- Department of Molecular Pharmacology and Physiology, University of South Florida, 560 Channelside Dr., Tampa, FL, 33602, USA
| | - Olha Kravtsova
- Department of Molecular Pharmacology and Physiology, University of South Florida, 560 Channelside Dr., Tampa, FL, 33602, USA
| | - Oleg Palygin
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA.,Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Alexander Staruschenko
- Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI, 53226, USA. .,Department of Molecular Pharmacology and Physiology, University of South Florida, 560 Channelside Dr., Tampa, FL, 33602, USA. .,Hypertension and Kidney Research Center, University of South Florida, Tampa, FL, 33602, USA. .,Clement J. Zablocki VA Medical Center, Milwaukee, WI, 53295, USA.
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6
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Lu Q, Yang Y, Zhang H, Chen C, Zhao J, Yang Z, Fan Y, Li L, Feng H, Zhu J, Yi S. Activation of GPR18 by Resolvin D2 Relieves Pain and Improves Bladder Function in Cyclophosphamide-Induced Cystitis Through Inhibiting TRPV1. Drug Des Devel Ther 2021; 15:4687-4699. [PMID: 34815664 PMCID: PMC8604640 DOI: 10.2147/dddt.s329507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 10/20/2021] [Indexed: 12/12/2022] Open
Abstract
Purpose Hyperalgesia and bladder overactivity are two main symptoms of interstitial cystitis/bladder pain syndrome (IC/BPS). Cannabinoid receptors participate in the modulation of pain and bladder function. GPR18, a member of the cannabinoid receptor family, also participates in the regulation of pain and bladder function, but its underlying mechanisms are unknown. In this work, we sought to study the role of GPR18 in IC/BPS. Methods A rat model of IC/BPS was established with cyclophosphamide (CYP). Paw withdrawal threshold (PWT) measurement and cystometry were used to evaluate pain and bladder function, respectively. RT-PCR, Western blotting and immunofluorescence were used to assess the expression and distribution of GPR18. The role of GPR18 in pain and bladder function was studied by intrathecal injection of resolvin D2 (RvD2, a GPR18 agonist) and O-1918 (a GPR18 antagonist). Calcium imaging was used to study the relationship between GPR18 and TRPV1. Results A rat model of IC/BPS, which exhibited a decreased PWT and micturition interval, was successfully established with CYP. The mRNA and protein expression of GPR18 was reduced in the bladder and dorsal root ganglia (DRG) in rats with CYP-induced cystitis. Intrathecal injection of RvD2 increased the PWT and micturition interval. However, O-1918 blocked the therapeutic effect of RvD2. GPR18 was present in bladder afferent nerves and colocalized with TRPV1 in DRG, and RvD2 decreased capsaicin-induced calcium influx in DRG. Conclusion Activation of GPR18 by RvD2 alleviated hyperalgesia and improved bladder function, possibly by inhibiting TRPV1 in rats with CYP-induced cystitis.
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Affiliation(s)
- Qudong Lu
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Yang Yang
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Hengshuai Zhang
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Cheng Chen
- Department of Burns, First Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Jiang Zhao
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Zhenxing Yang
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Yi Fan
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Longkun Li
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Huan Feng
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Jingzhen Zhu
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
| | - Shanhong Yi
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, People's Republic of China
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Christie S, Zagorodnyuk V. Time-of-day dependent changes in guinea pig bladder afferent mechano-sensitivity. Sci Rep 2021; 11:19283. [PMID: 34588547 PMCID: PMC8481311 DOI: 10.1038/s41598-021-98831-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/08/2021] [Indexed: 01/03/2023] Open
Abstract
The voiding of urine has a clear circadian rhythm with increased voiding during active phases and decreased voiding during inactive phases. Bladder spinal afferents play a key role in the regulation of bladder storage and voiding, but it is unknown whether they exhibit themselves a potential circadian rhythm. Therefore, this study aimed to determine the mechano- and chemo- sensitivity of three major bladder afferent classes at two opposite day-night time points. Adult female guinea pigs underwent conscious voiding monitoring and bladder ex vivo single unit extracellular afferent recordings at 0300 h and 1500 h to determine day-night modulation of bladder afferent activity. All guinea pigs voided a higher amount of urine at 1500 h compared to 0300 h. This was due to an increased number of voids at 1500 h. The mechano-sensitivity of low- and high-threshold stretch-sensitive muscular-mucosal bladder afferents to mucosal stroking and stretch was significantly higher at 1500 h compared to 0300 h. Low-threshold stretch-insensitive mucosal afferent sensitivity to stroking was significantly higher at 1500 h compared to 0300 h. Further, the chemosensitivity of mucosal afferents to N-Oleoyl Dopamine (endogenous TRPV1 agonist) was also significantly increased at 1500 h compared to 0300 h. This data indicates that bladder afferents exhibit a significant time-of-day dependent variation in mechano-sensitivity which may influence urine voiding patterns. Further studies across a 24 h period are warranted to reveal potential circadian rhythm modulation of bladder afferent activity.
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Affiliation(s)
- Stewart Christie
- Discipline of Human Physiology, Flinders Health & Medical Research Institute, College of Medicine and Public Health, Flinders University, GPO Box 2100, Adelaide, SA, Australia
| | - Vladimir Zagorodnyuk
- Discipline of Human Physiology, Flinders Health & Medical Research Institute, College of Medicine and Public Health, Flinders University, GPO Box 2100, Adelaide, SA, Australia.
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Christie S, Brookes S, Zagorodnyuk V. Endocannabinoids in Bladder Sensory Mechanisms in Health and Diseases. Front Pharmacol 2021; 12:708989. [PMID: 34290614 PMCID: PMC8287826 DOI: 10.3389/fphar.2021.708989] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 06/23/2021] [Indexed: 01/23/2023] Open
Abstract
The recent surge in research on cannabinoids may have been fueled by changes in legislation in several jurisdictions, and by approval for the use of cannabinoids for treatment of some chronic diseases. Endocannabinoids act largely, but not exclusively on cannabinoid receptors 1 and 2 (CBR1 and CBR2) which are expressed in the bladder mainly by the urothelium and the axons and endings of motor and sensory neurons. A growing body of evidence suggests that endocannabinoid system constitutively downregulates sensory bladder function during urine storage and micturition, under normal physiological conditions. Similarly, exogenous cannabinoid agonists have potent modulatory effects, as do inhibitors of endocannabinoid inactivation. Results suggest a high potential of cannabinoids to therapeutically ameliorate lower urinary tract symptoms in overactive bladder and painful bladder syndromes. At least part of this may be mediated via effects on sensory nerves, although actions on efferent nerves complicate interpretation. The sensory innervation of bladder is complex with at least eight classes identified. There is a large gap in our knowledge of the effects of endocannabinoids and synthetic agonists on different classes of bladder sensory neurons. Future studies are needed to reveal the action of selective cannabinoid receptor 2 agonists and/or peripherally restricted synthetic cannabinoid receptor 1 agonists on bladder sensory neurons in animal models of bladder diseases. There is significant potential for these novel therapeutics which are devoid of central nervous system psychotropic actions, and which may avoid many of the side effects of current treatments for overactive bladder and painful bladder syndromes.
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Affiliation(s)
- Stewart Christie
- Discipline of Human Physiology, College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, Adelaide, SA, Australia
| | - Simon Brookes
- Discipline of Human Physiology, College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, Adelaide, SA, Australia
| | - Vladimir Zagorodnyuk
- Discipline of Human Physiology, College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, Adelaide, SA, Australia
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