1
|
Hiyama TY. Brain sodium sensing for regulation of thirst, salt appetite, and blood pressure. Physiol Rep 2024; 12:e15970. [PMID: 38479999 PMCID: PMC10937250 DOI: 10.14814/phy2.15970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 02/29/2024] [Indexed: 03/17/2024] Open
Abstract
The brain possesses intricate mechanisms for monitoring sodium (Na) levels in body fluids. During prolonged dehydration, the brain detects variations in body fluids and produces sensations of thirst and aversions to salty tastes. At the core of these processes Nax , the brain's Na sensor, exists. Specialized neural nuclei, namely the subfornical organ (SFO) and organum vasculosum of the lamina terminalis (OVLT), which lack the blood-brain barrier, play pivotal roles. Within the glia enveloping the neurons in these regions, Nax collaborates with Na+ /K+ -ATPase and glycolytic enzymes to drive glycolysis in response to elevated Na levels. Lactate released from these glia cells activates nearby inhibitory neurons. The SFO hosts distinct types of angiotensin II-sensitive neurons encoding thirst and salt appetite, respectively. During dehydration, Nax -activated inhibitory neurons suppress salt-appetite neuron's activity, whereas salt deficiency reduces thirst neuron's activity through cholecystokinin. Prolonged dehydration increases the Na sensitivity of Nax via increased endothelin expression in the SFO. So far, patients with essential hypernatremia have been reported to lose thirst and antidiuretic hormone release due to Nax -targeting autoantibodies. Inflammation in the SFO underlies the symptoms. Furthermore, Nax activation in the OVLT, driven by Na retention, stimulates the sympathetic nervous system via acid-sensing ion channels, contributing to a blood pressure elevation.
Collapse
Affiliation(s)
- Takeshi Y. Hiyama
- Department of Integrative PhysiologyTottori University Graduate School and Faculty of MedicineYonagoJapan
| |
Collapse
|
2
|
Matsuda T, Kobayashi K, Kobayashi K, Noda M. Two parabrachial Cck neurons involved in the feedback control of thirst or salt appetite. Cell Rep 2024; 43:113619. [PMID: 38157299 DOI: 10.1016/j.celrep.2023.113619] [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: 02/23/2023] [Revised: 11/20/2023] [Accepted: 12/08/2023] [Indexed: 01/03/2024] Open
Abstract
Thirst and salt appetite are temporarily suppressed after water and salt ingestion, respectively, before absorption; however, the underlying neural mechanisms remain unclear. The parabrachial nucleus (PBN) is the relay center of ingestion signals from the digestive organs. We herein identify two distinct neuronal populations expressing cholecystokinin (Cck) mRNA in the lateral PBN that are activated in response to water and salt intake, respectively. The two Cck neurons in the dorsal-lateral compartment of the PBN project to the median preoptic nucleus and ventral part of the bed nucleus of the stria terminalis, respectively. The optogenetic stimulation of respective Cck neurons suppresses thirst or salt appetite under water- or salt-depleted conditions. The combination of optogenetics and in vivo Ca2+ imaging during ingestion reveals that both Cck neurons control GABAergic neurons in their target nuclei. These findings provide the feedback mechanisms for the suppression of thirst and salt appetite after ingestion.
Collapse
Affiliation(s)
- Takashi Matsuda
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Okazaki, Aichi 444-8585, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima, Fukushima 960-1295, Japan
| | - Masaharu Noda
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan.
| |
Collapse
|
3
|
Wang J, Lv F, Yin W, Gao Z, Liu H, Wang Z, Sun J. The organum vasculosum of the lamina terminalis and subfornical organ: regulation of thirst. Front Neurosci 2023; 17:1223836. [PMID: 37732311 PMCID: PMC10507174 DOI: 10.3389/fnins.2023.1223836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 08/22/2023] [Indexed: 09/22/2023] Open
Abstract
Thirst and water intake are regulated by the organum vasculosum of the lamina terminalis (OVLT) and subfornical organ (SFO), located around the anteroventral third ventricle, which plays a critical role in sensing dynamic changes in sodium and water balance in body fluids. Meanwhile, neural circuits involved in thirst regulation and intracellular mechanisms underlying the osmosensitive function of OVLT and SFO are reviewed. Having specific Nax channels in the glial cells and other channels (such as TRPV1 and TRPV4), the OVLT and SFO detect the increased Na+ concentration or hyperosmolality to orchestrate osmotic stimuli to the insular and cingulate cortex to evoke thirst. Meanwhile, the osmotic stimuli are relayed to the supraoptic nucleus (SON) and paraventricular nucleus of the hypothalamus (PVN) via direct neural projections or the median preoptic nucleus (MnPO) to promote the secretion of vasopressin which plays a vital role in the regulation of body fluid homeostasis. Importantly, the vital role of OVLT in sleep-arousal regulation is discussed, where vasopressin is proposed as the mediator in the regulation when OVLT senses osmotic stimuli.
Collapse
Affiliation(s)
- Jiaxu Wang
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Fenglin Lv
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Wei Yin
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Zhanpeng Gao
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
| | - Hongyu Liu
- Institute of Sport and Exercise Medicine, North University of China, Taiyuan, China
| | - Zhen Wang
- Department of Cardiology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Jinhao Sun
- Department of Anatomy and Neurobiology, School of Medicine, Shandong University, Jinan, Shandong, China
| |
Collapse
|
4
|
Jin X, Xie J, Yeh CW, Chen JC, Cheng CJ, Lien CC, Huang CL. WNK1 promotes water homeostasis by acting as a central osmolality sensor for arginine vasopressin release. J Clin Invest 2023; 133:e164222. [PMID: 37071482 PMCID: PMC10231991 DOI: 10.1172/jci164222] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 04/14/2023] [Indexed: 04/19/2023] Open
Abstract
Maintaining internal osmolality constancy is essential for life. Release of arginine vasopressin (AVP) in response to hyperosmolality is critical. Current hypotheses for osmolality sensors in circumventricular organs (CVOs) of the brain focus on mechanosensitive membrane proteins. The present study demonstrated that intracellular protein kinase WNK1 was involved. Focusing on vascular-organ-of-lamina-terminalis (OVLT) nuclei, we showed that WNK1 kinase was activated by water restriction. Neuron-specific conditional KO (cKO) of Wnk1 caused polyuria with decreased urine osmolality that persisted in water restriction and blunted water restriction-induced AVP release. Wnk1 cKO also blunted mannitol-induced AVP release but had no effect on osmotic thirst response. The role of WNK1 in the osmosensory neurons in CVOs was supported by neuronal pathway tracing. Hyperosmolality-induced increases in action potential firing in OVLT neurons was blunted by Wnk1 deletion or pharmacological WNK inhibitors. Knockdown of Kv3.1 channel in OVLT by shRNA reproduced the phenotypes. Thus, WNK1 in osmosensory neurons in CVOs detects extracellular hypertonicity and mediates the increase in AVP release by activating Kv3.1 and increasing action potential firing from osmosensory neurons.
Collapse
Affiliation(s)
- Xin Jin
- Department of Medicine, Division of Nephrology, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Jian Xie
- Department of Medicine, Division of Nephrology, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | | | - Jen-Chi Chen
- Department of Medicine, Division of Nephrology, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Chih-Jen Cheng
- Department of Medicine, Division of Nephrology, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Cheng-Chang Lien
- Institute of Neuroscience and
- Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chou-Long Huang
- Department of Medicine, Division of Nephrology, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| |
Collapse
|
5
|
Wei Y, Khalaf AT, Rui C, Abdul Kadir SY, Zainol J, Oglah Z. The Emergence of TRP Channels Interactome as a Potential Therapeutic Target in Pancreatic Ductal Adenocarcinoma. Biomedicines 2023; 11:biomedicines11041164. [PMID: 37189782 DOI: 10.3390/biomedicines11041164] [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: 03/05/2023] [Revised: 04/04/2023] [Accepted: 04/06/2023] [Indexed: 05/17/2023] Open
Abstract
Integral membrane proteins, known as Transient Receptor Potential (TRP) channels, are cellular sensors for various physical and chemical stimuli in the nervous system, respiratory airways, colon, pancreas, bladder, skin, cardiovascular system, and eyes. TRP channels with nine subfamilies are classified by sequence similarity, resulting in this superfamily's tremendous physiological functional diversity. Pancreatic Ductal Adenocarcinoma (PDAC) is the most common and aggressive form of pancreatic cancer. Moreover, the development of effective treatment methods for pancreatic cancer has been hindered by the lack of understanding of the pathogenesis, partly due to the difficulty in studying human tissue samples. However, scientific research on this topic has witnessed steady development in the past few years in understanding the molecular mechanisms that underlie TRP channel disturbance. This brief review summarizes current knowledge of the molecular role of TRP channels in the development and progression of pancreatic ductal carcinoma to identify potential therapeutic interventions.
Collapse
Affiliation(s)
- Yuanyuan Wei
- Basic Medical College, Chengdu University, Chengdu 610106, China
| | | | - Cao Rui
- Basic Medical College, Chengdu University, Chengdu 610106, China
| | - Samiah Yasmin Abdul Kadir
- Faculty of Medicine, Widad University College, BIM Point, Bandar Indera Mahkota, Kuantan 25200, Malaysia
| | - Jamaludin Zainol
- Faculty of Medicine, Widad University College, BIM Point, Bandar Indera Mahkota, Kuantan 25200, Malaysia
| | - Zahraa Oglah
- School of Science, Auckland University of Technology (AUT), 55 Wellesley Street, Auckland 1010, New Zealand
| |
Collapse
|
6
|
Nikolovska K, Seidler UE, Stock C. The Role of Plasma Membrane Sodium/Hydrogen Exchangers in Gastrointestinal Functions: Proliferation and Differentiation, Fluid/Electrolyte Transport and Barrier Integrity. Front Physiol 2022; 13:899286. [PMID: 35665228 PMCID: PMC9159811 DOI: 10.3389/fphys.2022.899286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 04/19/2022] [Indexed: 12/11/2022] Open
Abstract
The five plasma membrane Na+/H+ exchanger (NHE) isoforms in the gastrointestinal tract are characterized by distinct cellular localization, tissue distribution, inhibitor sensitivities, and physiological regulation. NHE1 (Slc9a1) is ubiquitously expressed along the gastrointestinal tract in the basolateral membrane of enterocytes, but so far, an exclusive role for NHE1 in enterocyte physiology has remained elusive. NHE2 (Slc9a2) and NHE8 (Slc9a8) are apically expressed isoforms with ubiquitous distribution along the colonic crypt axis. They are involved in pHi regulation of intestinal epithelial cells. Combined use of a knockout mouse model, intestinal organoid technology, and specific inhibitors revealed previously unrecognized actions of NHE2 and NHE8 in enterocyte proliferation and differentiation. NHE3 (Slc9a3), expressed in the apical membrane of differentiated intestinal epithelial cells, functions as the predominant nutrient-independent Na+ absorptive mechanism in the gut. The new selective NHE3 inhibitor (Tenapanor) allowed discovery of novel pathophysiological and drug-targetable NHE3 functions in cystic-fibrosis associated intestinal obstructions. NHE4, expressed in the basolateral membrane of parietal cells, is essential for parietal cell integrity and acid secretory function, through its role in cell volume regulation. This review focuses on the expression, regulation and activity of the five plasma membrane Na+/H+ exchangers in the gastrointestinal tract, emphasizing their role in maintaining intestinal homeostasis, or their impact on disease pathogenesis. We point to major open questions in identifying NHE interacting partners in central cellular pathways and processes and the necessity of determining their physiological role in a system where their endogenous expression/activity is maintained, such as organoids derived from different parts of the gastrointestinal tract.
Collapse
|
7
|
NODA M, MATSUDA T. Central regulation of body fluid homeostasis. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2022; 98:283-324. [PMID: 35908954 PMCID: PMC9363595 DOI: 10.2183/pjab.98.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Extracellular fluids, including blood, lymphatic fluid, and cerebrospinal fluid, are collectively called body fluids. The Na+ concentration ([Na+]) in body fluids is maintained at 135-145 mM and is broadly conserved among terrestrial animals. Homeostatic osmoregulation by Na+ is vital for life because severe hyper- or hypotonicity elicits irreversible organ damage and lethal neurological trauma. To achieve "body fluid homeostasis" or "Na homeostasis", the brain continuously monitors [Na+] in body fluids and controls water/salt intake and water/salt excretion by the kidneys. These physiological functions are primarily regulated based on information on [Na+] and relevant circulating hormones, such as angiotensin II, aldosterone, and vasopressin. In this review, we discuss sensing mechanisms for [Na+] and hormones in the brain that control water/salt intake behaviors, together with the responsible sensors (receptors) and relevant neural pathways. We also describe mechanisms in the brain by which [Na+] increases in body fluids activate the sympathetic neural activity leading to hypertension.
Collapse
Affiliation(s)
- Masaharu NODA
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa, Japan
- Correspondence should be addressed to: Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, Kanagawa 226-8503, Japan (e-mail: )
| | - Takashi MATSUDA
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa, Japan
| |
Collapse
|
8
|
Dolivo D, Rodrigues A, Sun L, Li Y, Hou C, Galiano R, Hong SJ, Mustoe T. The Na x (SCN7A) channel: an atypical regulator of tissue homeostasis and disease. Cell Mol Life Sci 2021; 78:5469-5488. [PMID: 34100980 PMCID: PMC11072345 DOI: 10.1007/s00018-021-03854-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 04/15/2021] [Accepted: 05/08/2021] [Indexed: 12/15/2022]
Abstract
Within an articulately characterized family of ion channels, the voltage-gated sodium channels, exists a black sheep, SCN7A (Nax). Nax, in contrast to members of its molecular family, has lost its voltage-gated character and instead rapidly evolved a new function as a concentration-dependent sensor of extracellular sodium ions and subsequent signal transducer. As it deviates fundamentally in function from the rest of its family, and since the bulk of the impressive body of literature elucidating the pathology and biochemistry of voltage-gated sodium channels has been performed in nervous tissue, reports of Nax expression and function have been sparse. Here, we investigate available reports surrounding expression and potential roles for Nax activity outside of nervous tissue. With these studies as justification, we propose that Nax likely acts as an early sensor that detects loss of tissue homeostasis through the pathological accumulation of extracellular sodium and/or through endothelin signaling. Sensation of homeostatic aberration via Nax then proceeds to induce pathological tissue phenotypes via promotion of pro-inflammatory and pro-fibrotic responses, induced through direct regulation of gene expression or through the generation of secondary signaling molecules, such as lactate, that can operate in an autocrine or paracrine fashion. We hope that our synthesis of much of the literature investigating this understudied protein will inspire more research into Nax not simply as a biochemical oddity, but also as a potential pathophysiological regulator and therapeutic target.
Collapse
Affiliation(s)
- David Dolivo
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Adrian Rodrigues
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Lauren Sun
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Yingxing Li
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Chun Hou
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
- Department of Plastic and Cosmetic Surgery, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Robert Galiano
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA
| | - Seok Jong Hong
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA.
- , 300 E. Superior St., Chicago, IL, 60611, USA.
| | - Thomas Mustoe
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, USA.
- , 737 N. Michigan Ave., Chicago, IL, 60611, USA.
| |
Collapse
|
9
|
Kinaneh S, Knany Y, Khoury EE, Ismael-Badarneh R, Hamoud S, Berger G, Abassi Z, Azzam ZS. Identification, localization and expression of NHE isoforms in the alveolar epithelial cells. PLoS One 2021; 16:e0239240. [PMID: 33882062 PMCID: PMC8059851 DOI: 10.1371/journal.pone.0239240] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 04/02/2021] [Indexed: 02/06/2023] Open
Abstract
Na+/H+ exchangers (NHEs), encoded by Solute Carrier 9A (SLC9A) genes in human, are ubiquitous integral membrane ion transporters that mediate the electroneutral exchange of H+ with Na+ or K+. NHEs, found in the kidney and intestine, play a major role in the process of fluid reabsorption together via Na+,K+-ATPase pump and Na+ channels. Nevertheless, the expression pattern of NHE in the lung and its role in alveolar fluid homeostasis has not been addressed. Therefore, we aimed to examine the expression of NHE specific isoforms in alveolar epithelial cells (AECs), and assess their role in congestive heart failure (CHF). Three NHE isoforms were identified in AEC and A549 cell line, at the level of protein and mRNA; NHE1, NHE2 and mainly NHE8, the latter was shown to be localized in the apical membrane of AEC. Treating A549 cells with angiotensin (Ang) II for 3, 5 and 24 hours displayed a significant reduction in NHE8 protein abundance. Moreover, the abundance of NHE8 protein was downregulated in A549 cells that were treated overnight with Ang II. NHE8 abundance in whole lung lysate was increased in rats with 1-week CHF compared to sham operated rats. However, lower abundance of NHE8 was observed in 4-week CHF group. In conclusion, we herein show for the first time, the expression of a novel NHE isoform in AEC, namely NHE8. Notably, Ang II decreased NHE8 protein levels. Moreover, NHE8 was distinctly affected in CHF rats, probably depending on the severity of the heart failure.
Collapse
Affiliation(s)
- Safa Kinaneh
- Ruth & Bruce Rappaport Faculty of Medicine, Department of Physiology, Technion, Israel Institute of Technology, Haifa, Israel
| | - Yara Knany
- Ruth & Bruce Rappaport Faculty of Medicine, Department of Physiology, Technion, Israel Institute of Technology, Haifa, Israel
| | - Emad E. Khoury
- Ruth & Bruce Rappaport Faculty of Medicine, Department of Physiology, Technion, Israel Institute of Technology, Haifa, Israel
| | | | - Shadi Hamoud
- Ruth & Bruce Rappaport Faculty of Medicine, Department of Physiology, Technion, Israel Institute of Technology, Haifa, Israel
- Internal Medicine “E”, Rambam: Human Health Care Campus, Haifa, Israel
| | - Gidon Berger
- Ruth & Bruce Rappaport Faculty of Medicine, Department of Physiology, Technion, Israel Institute of Technology, Haifa, Israel
- Internal Medicine “B”, Rambam: Human Health Care Campus, Haifa, Israel
| | - Zaid Abassi
- Ruth & Bruce Rappaport Faculty of Medicine, Department of Physiology, Technion, Israel Institute of Technology, Haifa, Israel
| | - Zaher S. Azzam
- Ruth & Bruce Rappaport Faculty of Medicine, Department of Physiology, Technion, Israel Institute of Technology, Haifa, Israel
- Internal Medicine “B”, Rambam: Human Health Care Campus, Haifa, Israel
- * E-mail:
| |
Collapse
|
10
|
Hou C, Dolivo D, Rodrigues A, Li Y, Leung K, Galiano R, Hong SJ, Mustoe T. Knockout of sodium channel Na x delays re-epithelializathion of splinted murine excisional wounds. Wound Repair Regen 2020; 29:306-315. [PMID: 33378794 DOI: 10.1111/wrr.12885] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/02/2020] [Accepted: 12/07/2020] [Indexed: 01/29/2023]
Abstract
Mammalian wound healing is a carefully orchestrated process in which many cellular and molecular effectors respond in concert to perturbed tissue homeostasis in order to close the wound and re-establish the skin barrier. The roles of many of these molecular effectors, however, are not entirely understood. Our lab previously demonstrated that the atypical sodium channel Nax (encoded by Scn7a) responds to wound-induced epidermal dehydration, resulting in molecular cascades that drive pro-inflammatory signaling. Acute inhibition of Nax was sufficient to attenuate dermatopathological symptoms in models of hypertrophic scar and dermatitis. To date, however, the role of Nax in excisional wound healing has not been demonstrated. Here we report development of a knockout mouse that lacks expression of functional Nax , and we demonstrate that lack of functional Nax results in deficient wound healing in a murine splinted excisional wound healing model. This deficiency in wound healing was reflected in impaired re-epithelialization and decreased keratinocyte proliferation, a finding which was further supported by decreased proliferation upon Nax knockdown in HaCaT cells in vitro. Defective wound healing was observed alongside increased expression of inflammatory genes in the wound epidermis of Nax -/- mice, suggesting that mice lacking functional Nax retain the ability to undergo skin inflammation. Our observations here motivate further investigation into the roles of Nax in wound healing and other skin processes.
Collapse
Affiliation(s)
- Chun Hou
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA.,Department of Plastic and Cosmetic Surgery, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - David Dolivo
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Adrian Rodrigues
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Yingxing Li
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Kai Leung
- Division of Combat Wound Repair, US Army Institute of Surgical Research, JB Fort Sam Houston, San Antonio, Texas, USA
| | - Robert Galiano
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Seok Jong Hong
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| | - Thomas Mustoe
- Department of Surgery, Northwestern University-Feinberg School of Medicine, Chicago, Illinois, USA
| |
Collapse
|
11
|
Fenrich M, Habjanovic K, Kajan J, Heffer M. The circle of Willis revisited: Forebrain dehydration sensing facilitated by the anterior communicating artery: How hemodynamic properties facilitate more efficient dehydration sensing in amniotes. Bioessays 2020; 43:e2000115. [PMID: 33191609 DOI: 10.1002/bies.202000115] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 10/10/2020] [Accepted: 10/13/2020] [Indexed: 12/14/2022]
Abstract
We hypothesize that threat of dehydration provided selection pressure for the evolutionary emergence and persistence of the anterior communicating artery (ACoA - the inter-arterial connection that completes the Circle of Willis) in early amniotes. The ACoA is a hemodynamically insignificant artery, but, as we argue in this paper, its privileged position outside the blood-brain barrier gives it a crucial sensing function for the osmolarity of the blood against the background of the rest of the brain, which efficiently protects itself from dehydration. Till now, the questions of why the ACoA evolved, and what its physiological function is, have remained unsatisfactorily answered. The traditional view-that the ACoA serves as a collateral source of vascularization in case of arterial stenosis-is anthropocentric, and not in accordance with principles of natural selection that apply more generally. Diseases underlying arterial stenosis are associated with aging and the human lifestyle, so this cannot explain why the ACoA formed hundreds of millions of years ago and persisted in amniotes to this day. The peculiar hemodynamic properties of the ACoA could be selected traits that allowed for more efficient forebrain detection of dehydration and complex behavioral responses to water loss, a major advantage in the survival of early amniotes. This hypothesis also explains insufficient hydration often seen in elderly humans.
Collapse
Affiliation(s)
- Matija Fenrich
- Laboratory of Neurobiology, Faculty of Medicine, J. J. Strossmayer University of Osijek, Osijek, Croatia
| | - Karlo Habjanovic
- Laboratory of Neurobiology, Faculty of Medicine, J. J. Strossmayer University of Osijek, Osijek, Croatia
| | - Josip Kajan
- Laboratory of Neurobiology, Faculty of Medicine, J. J. Strossmayer University of Osijek, Osijek, Croatia
| | - Marija Heffer
- Laboratory of Neurobiology, Faculty of Medicine, J. J. Strossmayer University of Osijek, Osijek, Croatia
| |
Collapse
|
12
|
Matsuda T, Hiyama TY, Kobayashi K, Kobayashi K, Noda M. Distinct CCK-positive SFO neurons are involved in persistent or transient suppression of water intake. Nat Commun 2020; 11:5692. [PMID: 33173030 PMCID: PMC7655816 DOI: 10.1038/s41467-020-19191-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 10/02/2020] [Indexed: 01/29/2023] Open
Abstract
The control of water-intake behavior is critical for life because an excessive water intake induces pathological conditions, such as hyponatremia or water intoxication. However, the brain mechanisms controlling water intake currently remain unclear. We previously reported that thirst-driving neurons (water neurons) in the subfornical organ (SFO) are cholecystokinin (CCK)-dependently suppressed by GABAergic interneurons under Na-depleted conditions. We herein show that CCK-producing excitatory neurons in the SFO stimulate the activity of GABAergic interneurons via CCK-B receptors. Fluorescence-microscopic Ca2+ imaging demonstrates two distinct subpopulations in CCK-positive neurons in the SFO, which are persistently activated under hyponatremic conditions or transiently activated in response to water drinking, respectively. Optical and chemogenetic silencings of the respective types of CCK-positive neurons both significantly increase water intake under water-repleted conditions. The present study thus reveals CCK-mediated neural mechanisms in the central nervous system for the control of water-intake behaviors. Water intake is critical to our life, and the subfornical organ in the brain involved in the control of this behavior. Here, the authors reveal that two distinct groups of CCK-producing neurons in the SFO suppress water intake according to the physiological condition or water-intake stimulus.
Collapse
Affiliation(s)
- Takashi Matsuda
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa, 226-8503, Japan.,Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi, 444-8787, Japan
| | - Takeshi Y Hiyama
- Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi, 444-8787, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, National Institute for Physiological Sciences, Okazaki, Aichi, 444-8585, Japan
| | - Kazuto Kobayashi
- Department of Molecular Genetics, Institute of Biomedical Sciences, Fukushima Medical University School of Medicine, Fukushima, Fukushima, 960-1295, Japan
| | - Masaharu Noda
- Homeostatic Mechanism Research Unit, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa, 226-8503, Japan. .,Division of Molecular Neurobiology, National Institute for Basic Biology, Okazaki, Aichi, 444-8787, Japan.
| |
Collapse
|