1
|
Ihara T, Shinozaki Y, Shigetomi E, Danjo Y, Tsuchiya S, Kanda M, Kamiyama M, Takeda M, Koizumi S, Mitsui T. G protein-coupled receptor 55 activated by palmitoylethanolamide is associated with the development of nocturia associated with circadian rhythm disorders. Life Sci 2023; 332:122072. [PMID: 37704067 DOI: 10.1016/j.lfs.2023.122072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/17/2023] [Accepted: 09/03/2023] [Indexed: 09/15/2023]
Abstract
AIMS Bladder function is regulated by clock genes and dysregulation of circadian bladder function can cause nocturia. The blood concentration of palmitoylethanolamide (PEA), a fatty acid metabolite, changes with circadian rhythm. Clock gene abnormalities demonstrate the highest PEA levels during the sleep phase. PEA is a GPR55 agonist that influences urination; therefore, increased PEA during the sleep phase may cause nocturia. Herein, we investigated the function of GPR55 to evaluate the relationship between GPR55 and nocturia that evoked higher PEA during the sleep phase in patients with circadian rhythm disorders. MAIN METHODS Male C57BL/6 mice were used. GPR55 localization was evaluated by immunofluorescence staining, qRT-PCR, and western blotting. Variations in PEA-induced intracellular Ca2+ concentrations were measured in primary cultured mouse urothelial cells (UCs) using Ca2+ imaging. PEA-induced NGF and PGI2 release in UCs was measured by ELISA. The micturition reflex pathway after PEA administration was evaluated using immunofluorescence staining. KEY FINDINGS GPR55 was predominant in the UC layer. PEA induced release of Ca2+ from the endoplasmic reticulum into the UC cytoplasm. ELISA and immunofluorescence staining revealed that NGF and PGI2 were released from bladder UCs, stimulated the pontine micturition center in mice, and induced nocturia. SIGNIFICANCE The loss of regular circadian metabolizing rhythm in fatty acids causes higher blood PEA levels during the sleep phase. Binding of PEA to GPR55 in UC may activate the downstream processes of the micturition reflex, leading to nocturia. These findings suggest a new mechanism for nocturia and its potential as a therapeutic target.
Collapse
Affiliation(s)
- Tatsuya Ihara
- Department of Urology, Toranomon Hospital Kajigaya, Kawasaki, Kanagawa 213-8587, Japan.
| | - Youichi Shinozaki
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Eiji Shigetomi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan
| | - Yosuke Danjo
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan
| | - Sachiko Tsuchiya
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan
| | - Mie Kanda
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan
| | - Manabu Kamiyama
- Department of Urology, Toranomon Hospital Kajigaya, Kawasaki, Kanagawa 213-8587, Japan
| | - Masayuki Takeda
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan
| | - Schuichi Koizumi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan
| | - Takahiko Mitsui
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi 409-3898, Japan
| |
Collapse
|
2
|
Ramsay S, Zagorodnyuk V. Role of circadian rhythms and melatonin in bladder function in heath and diseases. Auton Neurosci 2023; 246:103083. [PMID: 36871511 DOI: 10.1016/j.autneu.2023.103083] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/23/2023] [Accepted: 02/23/2023] [Indexed: 03/05/2023]
Abstract
The circadian system modulates all visceral organ physiological processes including urine storage and voiding. The "master clock" of the circadian system lies within suprachiasmatic nucleus of the hypothalamus while "peripheral clocks" are found in most peripheral tissue and organs, including the urinary bladder. Disruptions of circadian rhythms can cause organ malfunction and disorder or exacerbate pre-existing ones. It has been suggested that nocturia, which develops mostly in the elderly, could be a circadian-related disorder of the bladder. In the bladder, many types of gap junctions and ion channels in the detrusor, urothelium and sensory nerves are likely under strict local peripheral circadian control. The pineal hormone, melatonin, is a circadian rhythm synchroniser capable of controlling a variety of physiological processes in the body. Melatonin predominantly acts via the melatonin 1 and melatonin 2 G-protein coupled receptors expressed in the central nervous system, and many peripheral organs and tissues. Melatonin could be beneficial in the treatment of nocturia and other common bladder disorders. The ameliorating action of melatonin on bladder function is likely due to multiple mechanisms which include central effects on voiding and peripheral effects on the detrusor and bladder afferents. More studies are warranted to determine the precise mechanisms of circadian rhythm coordination of the bladder function and melatonin influences on the bladder in health and diseases.
Collapse
Affiliation(s)
- Stewart Ramsay
- 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.
| |
Collapse
|
3
|
Wang X, Dong YT, Hu XM, Zhang JZ, Shi NR, Zuo YQ, Wang X. The circadian regulation of extracellular ATP. Purinergic Signal 2023; 19:283-295. [PMID: 35939197 PMCID: PMC9984637 DOI: 10.1007/s11302-022-09881-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 06/24/2022] [Indexed: 11/25/2022] Open
Abstract
Extracellular ATP is a potent signaling molecule released from various cells throughout the body and is intimately involved in the pathophysiological functions of the nervous system and immune system by activating P2 purinergic receptors. Recent increasingly studies showed that extracellular ATP exhibits circadian oscillation with an approximately 24-h periodicity, which participates in regulatory pathways of central oscillator suprachiasmatic nucleus and peripheral oscillator bladder, respectively. Oscillators modulate the protein expression of ATP release channels and ectonucleotidase activity through clock genes; indeed, real-time alterations of ATP release and degradation determine outcomes of temporal character on extracellular ATP rhythm. The regulatory pathways on extracellular ATP rhythm are different in central and peripheral systems. In this review, we summarize the circadian rhythm of extracellular ATP and discuss several circadian regulatory pathways in different organs via ATP release and degradation, to provide a new understanding for purinergic signaling in the regulatory mechanism of circadian rhythm and a potential target to research the circadian regulation of extracellular ATP in other circadian oscillators.
Collapse
Affiliation(s)
- Xin Wang
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, 37 Shi-er Qiao Road, Chengdu, 610075 China
| | - Yu-Ting Dong
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, 37 Shi-er Qiao Road, Chengdu, 610075 China
| | - Xiu-Ming Hu
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, 37 Shi-er Qiao Road, Chengdu, 610075 China
| | - Ji-Zhou Zhang
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, 37 Shi-er Qiao Road, Chengdu, 610075 China
| | - Nan-Rui Shi
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, 37 Shi-er Qiao Road, Chengdu, 610075 China
| | - Yan-Qin Zuo
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, 37 Shi-er Qiao Road, Chengdu, 610075 China
| | - Xu Wang
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, 37 Shi-er Qiao Road, Chengdu, 610075 China
| |
Collapse
|
4
|
Ihara T, Shimura H, Tsuchiya S, Kanda M, Kira S, Sawada N, Takeda M, Mitsui T, Shigetomi E, Shinozaki Y, Koizumi S. Effects of fatty acid metabolites on nocturia. Sci Rep 2022; 12:3050. [PMID: 35197540 PMCID: PMC8866436 DOI: 10.1038/s41598-022-07096-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 02/11/2022] [Indexed: 12/05/2022] Open
Abstract
Dysregulation of circadian rhythm can cause nocturia. Levels of fatty acid metabolites, such as palmitoylethanolamide (PEA), 9-hydroxy-10E,12Z-octadecadienoic acid (9-HODE), and 4-hydroxy-5E,7Z,10Z,13Z,16Z,19Z-docosahexaenoic acid (4-HDoHE), are higher in the serum of patients with nocturia; however, the reason remains unknown. Here, we investigated the circadian rhythm of fatty acid metabolites and their effect on voiding in mice. WT and Clock mutant (ClockΔ19/Δ19) mice, a model for nocturia with circadian rhythm disorder, were used. Levels of serum PEA, 9-HODE, and 4-HDoHEl were measured every 8 h using LC/MS. Voiding pattern was recorded using metabolic cages after administration of PEA, 9-HODE, and 4-HDoHE to WT mice. Levels of serum PEA and 9-HODE fluctuated with circadian rhythm in WT mice, which were lower during the light phase. In contrast, circadian PEA and 9-HODE level deteriorated or retreated in ClockΔ19/Δ19 mice. Levels of serum PEA, 9-HODE, and 4-HDoHE were higher in ClockΔ19/Δ19 than in WT mice. Voiding frequency increased in PEA- and 4-HDoHE-administered mice. Bladder capacity decreased in PEA-administered mice. The changes of these bladder functions in mice were similar to those in elderly humans with nocturia. These findings highlighted the novel effect of lipids on the pathology of nocturia. These may be used for development of biomarkers and better therapies for nocturia.
Collapse
Affiliation(s)
- Tatsuya Ihara
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan.
| | - Hiroshi Shimura
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan
| | - Sachiko Tsuchiya
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan
| | - Mie Kanda
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan
| | - Satoru Kira
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan
| | - Norifumi Sawada
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan
| | - Masayuki Takeda
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan
| | - Takahiko Mitsui
- Department of Urology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan
| | - Eiji Shigetomi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Yoichi Shinozaki
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Schuichi Koizumi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo, Yamanashi, Japan
| |
Collapse
|
5
|
Different effects of GsMTx4 on nocturia associated with the circadian clock and Piezo1 expression in mice. Life Sci 2021; 278:119555. [PMID: 33930366 DOI: 10.1016/j.lfs.2021.119555] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/06/2021] [Accepted: 04/19/2021] [Indexed: 11/23/2022]
Abstract
OBJECTIVES Nocturia is a major problem in geriatric patients. Clock genes regulate circadian bladder function and Piezo type mechanosensitive ion channel component 1 (Piezo1) that senses bladder fullness. We utilized WT and Clock mutant (ClockΔ19/Δ19: nocturia phenotype) mice to determine if the effects of GsMTx4, a Piezo1 inhibitor, is dependent on circadian Piezo1 expression in the bladder. METHODS We compared voiding behavior in mice after the administration of vehicle, low dose, or high dose of GsMTx4. Intraperitoneal injections (IP) were performed at Zeitgeber time (ZT) 0, lower Piezo1 expression phase (ZT0-IP) and ZT12, higher Piezo1 expression phase (ZT12-IP). Urine volume (Uvol), voiding frequency (VF), and urine volume per void (Uvol/v) were measured using metabolic cages. RESULTS VF decreased at ZT12-IP in WT mice only with high dose of GsMTx4 but showed no effects in ClockΔ19/Δ19 mice. VF decreased significantly at ZT0-IP in WT mice after both doses, but only decreased after high dose in ClockΔ19/Δ19 mice. Uvol/v increased in WT mice at ZT0-IP after both doses and at ZT12-IP after high dose. Uvol/v increased in ClockΔ19/Δ19 mice only at ZT0-IP after high dose. GsMTx4 did not affect Uvol in both mice at ZT12-IP. A decrease in Uvol was observed in both mice at ZT0-IP; however, it was unrelated to GsMTx4-IP. CONCLUSIONS The effects of GsMTx4 changed associated with the circadian clock and Piezo1 expression level. The maximum effect occurred during sleep phase in WT. These results may lead to new therapeutic strategies against nocturia.
Collapse
|
6
|
Wu Y, Qi J, Wu C, Rong W. Emerging roles of the TRPV4 channel in bladder physiology and dysfunction. J Physiol 2021; 599:39-47. [PMID: 33052604 DOI: 10.1113/jp279776] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 10/06/2020] [Indexed: 12/17/2022] Open
Abstract
The transient receptor potential vanilloid type 4, TRPV4, is a polymodal cation channel which can be activated by diverse stimuli including mechanical, thermal and chemical cues. In the urinary bladder, TRPV4 is not only abundantly expressed in the urothelium but may also be localized in subepithelium, detrusor smooth muscles and afferent neurons. Emerging evidence indicates that the TRPV4 channel plays a sensory role in the uroepithelium, where it may regulate the release of sensory mediators such as ATP, which in turn modulates afferent nerve activity in response to bladder filling during the urination cycle. TRPV4 may also directly regulate detrusor contractility and the urothelial barrier function. Altered TRPV4 expression has been detected in various pathological bladder conditions. As such, TRPV4 may be a promising therapeutic target for bladder dysfunctions.
Collapse
Affiliation(s)
- Yanyuan Wu
- Department of Urology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Department of Anatomy and Physiology, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jun Qi
- Department of Urology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Changhao Wu
- School of Biosciences and Medicine, University of Surrey, Guildford, UK
| | - Weifang Rong
- Department of Urology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Department of Anatomy and Physiology, Shanghai Jiaotong University School of Medicine, Shanghai, China
| |
Collapse
|
7
|
Dalghi MG, Montalbetti N, Carattino MD, Apodaca G. The Urothelium: Life in a Liquid Environment. Physiol Rev 2020; 100:1621-1705. [PMID: 32191559 PMCID: PMC7717127 DOI: 10.1152/physrev.00041.2019] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/02/2020] [Accepted: 03/14/2020] [Indexed: 02/08/2023] Open
Abstract
The urothelium, which lines the renal pelvis, ureters, urinary bladder, and proximal urethra, forms a high-resistance but adaptable barrier that surveils its mechanochemical environment and communicates changes to underlying tissues including afferent nerve fibers and the smooth muscle. The goal of this review is to summarize new insights into urothelial biology and function that have occurred in the past decade. After familiarizing the reader with key aspects of urothelial histology, we describe new insights into urothelial development and regeneration. This is followed by an extended discussion of urothelial barrier function, including information about the roles of the glycocalyx, ion and water transport, tight junctions, and the cellular and tissue shape changes and other adaptations that accompany expansion and contraction of the lower urinary tract. We also explore evidence that the urothelium can alter the water and solute composition of urine during normal physiology and in response to overdistension. We complete the review by providing an overview of our current knowledge about the urothelial environment, discussing the sensor and transducer functions of the urothelium, exploring the role of circadian rhythms in urothelial gene expression, and describing novel research tools that are likely to further advance our understanding of urothelial biology.
Collapse
Affiliation(s)
- Marianela G Dalghi
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Nicolas Montalbetti
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Marcelo D Carattino
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Gerard Apodaca
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| |
Collapse
|
8
|
Hasuzawa N, Moriyama S, Moriyama Y, Nomura M. Physiopathological roles of vesicular nucleotide transporter (VNUT), an essential component for vesicular ATP release. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183408. [PMID: 32652056 DOI: 10.1016/j.bbamem.2020.183408] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 06/29/2020] [Accepted: 06/30/2020] [Indexed: 02/06/2023]
Abstract
Vesicular nucleotide transporter (VNUT) is the last identified member of the SLC17 organic anion transporter family, which plays a central role in vesicular storage in ATP-secreting cells. The discovery of VNUT demonstrated that, despite having been neglected for a long time, vesicular ATP release represents a major pathway for purinergic chemical transmission, which had been mainly attributed to ATP permeation channels. This article summarizes recent advances in our understanding of the mechanism of VNUT and its physiopathological roles as well as the development of inhibitors. Regulating the activity and/or the expression of VNUT represents a new and promising therapeutic strategy for the treatment of multiple diseases.
Collapse
Affiliation(s)
- Nao Hasuzawa
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan.
| | - Sawako Moriyama
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan
| | - Yoshinori Moriyama
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan
| | - Masatoshi Nomura
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kurume University School of Medicine, Kurume 830-0011, Japan
| |
Collapse
|
9
|
Voets T, Vriens J, Vennekens R. Targeting TRP Channels - Valuable Alternatives to Combat Pain, Lower Urinary Tract Disorders, and Type 2 Diabetes? Trends Pharmacol Sci 2019; 40:669-683. [PMID: 31395287 DOI: 10.1016/j.tips.2019.07.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/12/2019] [Accepted: 07/10/2019] [Indexed: 12/18/2022]
Abstract
Transient receptor potential (TRP) channels are a family of functionally diverse and widely expressed cation channels involved in a variety of cell signaling and sensory pathways. Research in the last two decades has not only shed light on the physiological roles of the 28 mammalian TRP channels, but also revealed the involvement of specific TRP channels in a plethora of inherited and acquired human diseases. Considering the historical successes of other types of ion channels as therapeutic drug targets, small molecules that target specific TRP channels hold promise as treatments for a variety of human conditions. In recent research, important new findings have highlighted the central role of TRP channels in chronic pain, lower urinary tract disorders, and type 2 diabetes, conditions with an unmet medical need. Here, we discuss how these advances support the development of TRP-channel-based pharmacotherapies as valuable alternatives to the current mainstays of treatment.
Collapse
Affiliation(s)
- Thomas Voets
- Laboratory of Ion Channel Research, VIB Center for Brain and Disease Research, Leuven, Belgium; Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium.
| | - Joris Vriens
- Laboratory of Endometrium, Endometriosis and Reproductive Medicine, Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Rudi Vennekens
- Laboratory of Ion Channel Research, VIB Center for Brain and Disease Research, Leuven, Belgium; Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| |
Collapse
|
10
|
Intermittent restraint stress induces circadian misalignment in the mouse bladder, leading to nocturia. Sci Rep 2019; 9:10069. [PMID: 31296902 PMCID: PMC6624370 DOI: 10.1038/s41598-019-46517-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 06/27/2019] [Indexed: 12/25/2022] Open
Abstract
Intermittent stress disrupts the circadian rhythm in clock genes such as Per2 only in peripheral organs without any effect on the central circadian clock in the suprachiasmatic nucleus. Here, the effect of restraint stress (RS) on circadian bladder function was investigated based on urination behavior and gene expression rhythms. Furthermore, PF670462 (PF), a Per2 phosphorylation enzyme inhibitor, was administered to investigate the effects on circadian bladder re-alignment after RS. Two-hour RS during the light (sleep) phase was applied to mice (RS mice) for 5 days. The following parameters were then examined: urination behaviors; clock gene expression rhythms and urinary sensory-related molecules such as piezo type mechanosensitive ion channel component 1 (Piezo1), transient receptor potential cation channel subfamily V member 4 (TRPV4), and Connexin26 (Cx26) in the bladder mucosa; Per2 expression in the excised bladder of Per2luciferase knock-in mice (Per2::luc); in vivo Per2 expression rhythms in the bladder of Per2::luc mice. Control mice did not show altered urination behavior in the light phase, whereas RS mice exhibited a higher voiding frequency and lower bladder capacity. In the bladder mucosa, RS mice also showed abrogated or misaligned Piezo1, TRPV4, Connexin26, and clock gene expression. The rhythmic expression of Per2 was also altered in RS mice both in excised- and in vivo bladder, compared with control mice. After PF administration, voiding frequency was reduced and bladder capacity was increased during the light phase in RS mice; the in vivo Per2 expression rhythm was also fully restored. Therefore, RS can alter circadian gene expression in the bladder during the light phase and might cause nocturia via changes in circadian bladder function due the dysregulation of clock genes. Amending the circadian rhythm therapeutically could be applied for nocturia.
Collapse
|