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Sauge E, White Z, Lizotte F, Yuen C, Atmuri NDP, Ciufolini MA, Geraldes P, Bernatchez P. Losartan and metabolite EXP3179 activate endothelial function without lowering blood pressure in AT2 receptor KO mice. Eur J Pharmacol 2024; 977:176663. [PMID: 38815786 DOI: 10.1016/j.ejphar.2024.176663] [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: 02/05/2024] [Revised: 05/22/2024] [Accepted: 05/22/2024] [Indexed: 06/01/2024]
Abstract
BACKGROUND We have documented profound release of nitric oxide (NO) and endothelium-derived hyperpolarization factor (EDHF) by angiotensin II (ANGII) receptor 1 (AT1) blocker (ARB) losartan and its unique metabolite EXP3179, a pleiotropic effect that may help rationalize the protective properties of ARBs. Since blood pressure (BP) lowering by ARBs likely require an ANGII-dependent switch from AT1 to ANGII receptor 2 (AT2) signaling, a receptor known to stimulate endothelial NO release, we investigated the contribution of AT1 and AT2 to losartan and EXP3179's endothelial function-activating properties. EXPERIMENTAL APPROACH Two AT1 ligands were used in an attempt to block the AT1-dependent endothelium-enhancing effects of EXP3179. AT2-null mice were used to evaluate the acute ex vivo and chronic in vivo effects of EXP3179 (20μM) and losartan (0.6 g/l), respectively, on endothelial function, BP and aortic stiffness. KEY RESULTS Ex vivo blockade of AT1 receptors did not attenuate EXP3179's effects on NO and EDHF-dependent endothelial function activation. We observed significant reductions in PE-induced contractility with EXP3179 in both WT and AT2 knockout (KO) aortic rings. In vivo, a 1-month chronic treatment with losartan did not affect pulse wave velocity (PWV) but decreased PE-induced contraction by 74.9 % in WT (p < 0.0001) and 47.3 % in AT2 KO (p < 0.05). Presence of AT2 was critical to losartan's BP lowering activity. CONCLUSION In contrast to BP lowering, the endothelial function-enhancing effects of losartan and EXP3179 are mostly independent of the classic ANGII/AT1/AT2 pathway, which sheds light on ARB pleiotropism.
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MESH Headings
- Animals
- Losartan/pharmacology
- Blood Pressure/drug effects
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Mice, Knockout
- Mice
- Receptor, Angiotensin, Type 2/metabolism
- Receptor, Angiotensin, Type 2/genetics
- Male
- Nitric Oxide/metabolism
- Receptor, Angiotensin, Type 1/metabolism
- Receptor, Angiotensin, Type 1/genetics
- Imidazoles/pharmacology
- Mice, Inbred C57BL
- Angiotensin II Type 1 Receptor Blockers/pharmacology
- Vascular Stiffness/drug effects
- Sulfonamides
- Thiophenes
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Affiliation(s)
- Elodie Sauge
- Department of Anesthesiology, Pharmacology & Therapeutics, D Department of Chemistry, University of British Columbia (UBC), Vancouver, Canada; Centre for Heart Lung Innovation, University of British Columbia (UBC), Vancouver, Canada
| | - Zoe White
- Department of Anesthesiology, Pharmacology & Therapeutics, D Department of Chemistry, University of British Columbia (UBC), Vancouver, Canada; Centre for Heart Lung Innovation, University of British Columbia (UBC), Vancouver, Canada
| | - Farah Lizotte
- Research Center of the Centre Hospitalier Universitaire de Sherbrooke, Québec, Canada
| | - Christopher Yuen
- Department of Anesthesiology, Pharmacology & Therapeutics, D Department of Chemistry, University of British Columbia (UBC), Vancouver, Canada; Centre for Heart Lung Innovation, University of British Columbia (UBC), Vancouver, Canada
| | - N D Prasad Atmuri
- Department of Medicine, Endocrinology Division, Université de Sherbrooke, Québec, Canada
| | - Marco A Ciufolini
- Department of Medicine, Endocrinology Division, Université de Sherbrooke, Québec, Canada
| | - Pedro Geraldes
- Research Center of the Centre Hospitalier Universitaire de Sherbrooke, Québec, Canada; Department of Medicine, Endocrinology Division, Université de Sherbrooke, Québec, Canada
| | - Pascal Bernatchez
- Department of Anesthesiology, Pharmacology & Therapeutics, D Department of Chemistry, University of British Columbia (UBC), Vancouver, Canada; Centre for Heart Lung Innovation, University of British Columbia (UBC), Vancouver, Canada.
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2
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Ramkissoon R, Cao S, Shah VH. The Pathophysiology of Portal Hypertension. Clin Liver Dis 2024; 28:369-381. [PMID: 38945632 DOI: 10.1016/j.cld.2024.03.001] [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] [Indexed: 07/02/2024]
Abstract
This article reviews the pathophysiology of portal hypertension that includes multiple mechanisms internal and external to the liver. This article starts with a review of literature describing the cellular and molecular mechanisms of portal hypertension, microvascular thrombosis, sinusoidal venous congestion, portal angiogenesis, vascular hypocontractility, and hyperdynamic circulation. Mechanotransduction and the gut-liver axis, which are newer areas of research, are reviewed. Dysfunction of this axis contributes to chronic liver injury, inflammation, fibrosis, and portal hypertension. Sequelae of portal hypertension are discussed in subsequent studies.
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Affiliation(s)
- Resham Ramkissoon
- Department of Gastroenterology & Hepatology, Mayo Clinic, 200 1st Street, SW, Rochester, MN 55902, USA
| | - Sheng Cao
- Mayo College of Medicine, Mayo Clinic, 200 1st Street, SW, Rochester, MN 55902, USA
| | - Vijay H Shah
- Department of Gastroenterology & Hepatology, Mayo Clinic, 200 1st Street, SW, Rochester, MN 55902, USA; Department of Internal Medicine, Mayo Clinic, 200 1st Street, SW, Rochester, MN 55902, USA.
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3
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Semenikhina M, Fedoriuk M, Stefanenko M, Klemens CA, Cherezova A, Marshall B, Hall G, Levchenko V, Solanki A, Lipschutz JH, Ilatovskaya DV, Staruschenko A, Palygin O. β-Arrestin pathway activation by selective ATR1 agonism promotes calcium influx in podocytes, leading to glomerular damage. Clin Sci (Lond) 2023; 137:1789-1804. [PMID: 38051199 PMCID: PMC11194114 DOI: 10.1042/cs20230313] [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: 03/28/2023] [Revised: 10/24/2023] [Accepted: 12/05/2023] [Indexed: 12/07/2023]
Abstract
Angiotensin receptor blockers (ARBs) are the first-line treatment for hypertension; they act by inhibiting signaling through the angiotensin 1 receptor (AT1R). Recently, a novel biased AT1R agonist, TRV120027 (TRV), which selectively activates the β-arrestin cascade and blocks the G-protein-coupled receptor pathway has been proposed as a potential blood pressure medication. Here, we explored the effects of TRV and associated β-arrestin signaling in podocytes, essential cells of the kidney filter. We used human podocyte cell lines to determine β-arrestin's involvement in calcium signaling and cytoskeletal reorganization and Dahl SS rats to investigate the chronic effects of TRV administration on glomerular health. Our experiments indicate that the TRV-activated β-arrestin pathway promotes the rapid elevation of intracellular Ca2+ in a dose-dependent manner. Interestingly, the amplitude of β-arrestin-mediated Ca2+ influx was significantly higher than the response to similar Ang II concentrations. Single-channel analyses show rapid activation of transient receptor potential canonical (TRPC) channels following acute TRV application. Furthermore, the pharmacological blockade of TRPC6 significantly attenuated the β-arrestin-mediated Ca2+ influx. Additionally, prolonged activation of the β-arrestin pathway in podocytes resulted in pathological actin cytoskeleton rearrangements, higher apoptotic cell markers, and augmented glomerular damage. TRV-activated β-arrestin signaling in podocytes may promote TRPC6 channel-mediated Ca2+ influx, foot process effacement, and apoptosis, possibly leading to severe defects in glomerular filtration barrier integrity and kidney health. Under these circumstances, the potential therapeutic application of TRV for hypertension treatment requires further investigation to assess the balance of the benefits versus possible deleterious effects and off-target damage.
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Affiliation(s)
- Marharyta Semenikhina
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC
| | - Mykhailo Fedoriuk
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC
| | - Mariia Stefanenko
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC
| | - Christine A. Klemens
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL
- Hypertension and Kidney Research Center, University of South Florida, Tampa, FL
| | - Alena Cherezova
- Department of Physiology, Medical College of Georgia, Augusta University, GA
| | - Brendan Marshall
- Department of Physiology, Medical College of Georgia, Augusta University, GA
| | - Gentzon Hall
- Division of Nephrology, Department of Internal Medicine, Duke University School of Medicine, Durham, NC
- Duke Molecular Physiology Institute, Duke University, Durham, NC
| | - Vladislav Levchenko
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL
| | - Ashish Solanki
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC
| | - Joshua H. Lipschutz
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC
- Ralph H. Johnson Veterans Affairs Medical Center, Charleston, SC
| | | | - Alexander Staruschenko
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL
- Hypertension and Kidney Research Center, University of South Florida, Tampa, FL
- James A. Haley Veterans’ Hospital, Tampa, FL
| | - Oleg Palygin
- Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC
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4
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Eissa AM, Hassanin MH, Ibrahim IAAEH. Hepatic β-arrestins: potential roles in liver health and disease. Mol Biol Rep 2023; 50:10399-10407. [PMID: 37843713 PMCID: PMC10676313 DOI: 10.1007/s11033-023-08898-0] [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: 05/29/2023] [Accepted: 10/04/2023] [Indexed: 10/17/2023]
Abstract
Β-arrestins are intracellular scaffolding proteins that have multifaceted roles in different types of disorders. In this review article, we gave a summary about the discovery, characterization and classification of these proteins and their intracellular functions. Moreover, this review article focused on the hepatic expression of β-arrestins and their hepatocellular distribution and function in each liver cell type. Also, we showed that β-arrestins are key regulators of distinct types of hepatic disorders. On the other hand, we addressed some important points that have never been studied before regarding the role of β-arrestins in certain types of hepatic disorders which needs more research efforts to cover.
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Affiliation(s)
| | | | - Islam A A E H Ibrahim
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Zagazig University, Zagazig, 44519, Egypt.
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5
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Hua F, Zhu H, Yu W, Zheng Q, Zhang L, Liang W, Lin Y, Xiao F, Yi P, Xiong Y, Dong Y, Li H, Fang L, Liu H, Ying J, Wang X. β-arrestin1 regulates astrocytic reactivity via Drp1-dependent mitochondrial fission: implications in postoperative delirium. J Neuroinflammation 2023; 20:113. [PMID: 37170230 PMCID: PMC10173541 DOI: 10.1186/s12974-023-02794-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 04/24/2023] [Indexed: 05/13/2023] Open
Abstract
Postoperative delirium (POD) is a frequent and debilitating complication, especially amongst high risk procedures, such as orthopedic surgery. This kind of neurocognitive disorder negatively affects cognitive domains, such as memory, awareness, attention, and concentration after surgery; however, its pathophysiology remains unknown. Multiple lines of evidence supporting the occurrence of inflammatory events have come forward from studies in human patients' brain and bio-fluids (CSF and serum), as well as in animal models for POD. β-arrestins are downstream molecules of guanine nucleotide-binding protein (G protein)-coupled receptors (GPCRs). As versatile proteins, they regulate numerous pathophysiological processes of inflammatory diseases by scaffolding with inflammation-linked partners. Here we report that β-arrestin1, one type of β-arrestins, decreases significantly in the reactive astrocytes of a mouse model for POD. Using β-arrestin1 knockout (KO) mice, we find aggravating effect of β-arrestin1 deficiency on the cognitive dysfunctions and inflammatory phenotype of astrocytes in POD model mice. We conduct the in vitro experiments to investigate the regulatory roles of β-arrestin1 and demonstrate that β-arrestin1 in astrocytes interacts with the dynamin-related protein 1 (Drp1) to regulate mitochondrial fusion/fission process. β-arrestin1 deletion cancels the combination of β-arrestin1 and cellular Drp1, thus promoting the translocation of Drp1 to mitochondrial membrane to provoke the mitochondrial fragments and the subsequent mitochondrial malfunctions. Using β-arrestin1-biased agonist, cognitive dysfunctions of POD mice and pathogenic activation of astrocytes in the POD-linked brain region are reduced. We, therefore, conclude that β-arrestin1 is a promising target for the understanding of POD pathology and development of POD therapeutics.
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Affiliation(s)
- Fuzhou Hua
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Hong Zhu
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, 330006, Nanchang, Jiangxi, People's Republic of China
| | - Wen Yu
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Qingcui Zheng
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Lieliang Zhang
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Weidong Liang
- Department of Anesthesiology, The First Affiliated Hospital of Gannan Medical University, Ganzhou, 341000, Jiangxi, People's Republic of China
| | - Yue Lin
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Fan Xiao
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Pengcheng Yi
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Yanhong Xiong
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Yao Dong
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Hua Li
- Department of Anesthesiology, First People's Hospital of Yihuang County, Fuzhou, 344400, Jiangxi, People's Republic of China
| | - Lanran Fang
- Department of Statistics, Jiangxi University of Finance and Economics, Nanchang, 330013, Jiangxi, People's Republic of China
| | - Hailin Liu
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Jun Ying
- Department of Anesthesiology, The Second Affiliated Hospital of Nanchang University, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China.
- Key Laboratory of Anesthesiology of Jiangxi Province, 1# Minde Road, Nanchang, 330006, Jiangxi, People's Republic of China.
| | - Xifeng Wang
- Department of Anesthesiology, The First Affiliated Hospital of Nanchang University, 17# Yong Wai Zheng Street, Nanchang, 330006, Jiangxi, People's Republic of China.
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6
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Structural Basis of the Interaction of the G Proteins, Gαi 1, Gβ 1γ 2 and Gαi 1β 1γ 2, with Membrane Microdomains and Their Relationship to Cell Localization and Activity. Biomedicines 2023; 11:biomedicines11020557. [PMID: 36831093 PMCID: PMC9953545 DOI: 10.3390/biomedicines11020557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 02/17/2023] Open
Abstract
GPCRs receive signals from diverse messengers and activate G proteins that regulate downstream signaling effectors. Efficient signaling is achieved through the organization of these proteins in membranes. Thus, protein-lipid interactions play a critical role in bringing G proteins together in specific membrane microdomains with signaling partners. Significantly, the molecular basis underlying the membrane distribution of each G protein isoform, fundamental to fully understanding subsequent cell signaling, remains largely unclear. We used model membranes with lipid composition resembling different membrane microdomains, and monomeric, dimeric and trimeric Gi proteins with or without single and multiple mutations to investigate the structural bases of G protein-membrane interactions. We demonstrated that cationic amino acids in the N-terminal region of the Gαi1 and C-terminal region of the Gγ2 subunit, as well as their myristoyl, palmitoyl and geranylgeranyl moieties, define the differential G protein form interactions with membranes containing different lipid classes (PC, PS, PE, SM, Cho) and the various microdomains they may form (Lo, Ld, PC bilayer, charged, etc.). These new findings in part explain the molecular basis underlying amphitropic protein translocation to membranes and localization to different membrane microdomains and the role of these interactions in cell signal propagation, pathophysiology and therapies targeted to lipid membranes.
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7
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Tehrani AY, Zhao R, Donen G, Bernatchez P. Heterogenous improvements in endothelial function by sub-blood pressure lowering doses of ARBs result in major anti-aortic root remodeling effects. Nitric Oxide 2023; 131:18-25. [PMID: 36565741 DOI: 10.1016/j.niox.2022.12.002] [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: 06/19/2022] [Revised: 11/30/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022]
Abstract
Low basal nitric oxide (NO) production is associated with a dysfunctional endothelium and vascular diseases. We have shown that some angiotensin II (AngII) receptor type 1 (AT1R) blockers (ARBs), a group of clinic-approved blood pressure (BP)-lowering medications, are also capable of activating endothelial function acutely and chronically, both ex vivo and in vivo, in pleiotropic, AngII-independent fashions, which suggested that endothelial function enhancement with ARBs may be independent of their well-documented BP lowering properties. Herein, we attempt to identify the most potent ARB at activating endothelial function when administered at sub-BP-lowering doses and determine its anti-aortic root remodeling properties in a model of Marfan syndrome (MFS). Amongst the 8 clinically available ARBs tested, only telmisartan and azilsartan induced significant (70% and 49%, respectively) NO-dependent inhibition of aortic contractility when administered for 4 weeks at sub-BP lowering, EC5 doses. Low-dose telmisartan (0.47 mg/kg) attenuated MFS-associated aortic root widening, medial thickening, and elastic fiber fragmentation to the same degree as high-dose telmisartan (10 mg/kg) despite wide differences in BP lowering between the two doses. Our study suggests that telmisartan is the most potent ARB at promoting increased endothelial function at low sub-BP doses and that it retained major aortic root widening inhibition activities. ARBs may enhance endothelial function independently from BP-lowering pathways, which could lead to new therapeutic approaches.
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Affiliation(s)
- Arash Y Tehrani
- Centre for Heart Lung Innovation, University of British Columbia, Vancouver, BC, Canada; Department of Anesthesiology, Pharmacology & Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | - Roy Zhao
- Centre for Heart Lung Innovation, University of British Columbia, Vancouver, BC, Canada; Department of Anesthesiology, Pharmacology & Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | - Graham Donen
- Centre for Heart Lung Innovation, University of British Columbia, Vancouver, BC, Canada; Department of Anesthesiology, Pharmacology & Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | - Pascal Bernatchez
- Centre for Heart Lung Innovation, University of British Columbia, Vancouver, BC, Canada; Department of Anesthesiology, Pharmacology & Therapeutics, University of British Columbia, Vancouver, BC, Canada.
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Sauerbruch T, Hennenberg M, Trebicka J, Schierwagen R. Beta-blockers in patients with liver cirrhosis: Pragmatism or perfection? Front Med (Lausanne) 2023; 9:1100966. [PMID: 36743678 PMCID: PMC9891090 DOI: 10.3389/fmed.2022.1100966] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 12/12/2022] [Indexed: 01/11/2023] Open
Abstract
With increasing decompensation, hyperdynamic circulatory disturbance occurs in liver cirrhosis despite activation of vasoconstrictors. Here, the concept of a therapy with non-selective beta-blockers was established decades ago. They lower elevated portal pressure, protect against variceal hemorrhage, and may also have pleiotropic immunomodulatory effects. Recently, the beneficial effect of carvedilol, which blocks alpha and beta receptors, has been highlighted. Carvedilol leads to "biased-signaling" via recruitment of beta-arrestin. This effect and its consequences have not been sufficiently investigated in patients with liver cirrhosis. Also, a number of questions remain open regarding the expression of beta-receptors and its intracellular signaling and the respective consequences in the intra- and extrahepatic tissue compartments. Despite the undisputed role of non-selective beta-blockers in the treatment of liver cirrhosis, we still can improve the knowledge as to when and how beta-blockers should be used in which patients.
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Affiliation(s)
- Tilman Sauerbruch
- Department of Internal Medicine I, University of Bonn, Bonn, Germany,*Correspondence: Tilman Sauerbruch,
| | - Martin Hennenberg
- Department of Urology, University Hospital, Ludwig Maximilian University of Munich, Munich, Germany
| | - Jonel Trebicka
- Department of Internal Medicine B, University of Münster, Münster, Germany,European Foundation for the Study of Chronic Liver Failure, Barcelona, Spain
| | - Robert Schierwagen
- Department of Internal Medicine B, University of Münster, Münster, Germany
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Liu S, Premont RT, Park KH, Rockey DC. β-PIX cooperates with GIT1 to regulate endothelial nitric oxide synthase in sinusoidal endothelial cells. Am J Physiol Gastrointest Liver Physiol 2022; 323:G511-G522. [PMID: 36044673 PMCID: PMC9639759 DOI: 10.1152/ajpgi.00034.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 08/11/2022] [Accepted: 08/24/2022] [Indexed: 01/31/2023]
Abstract
Previous studies have demonstrated that G protein-coupled receptor kinase interacting-1 protein (GIT1) associates with endothelial nitric oxide synthase (eNOS) to regulate nitric oxide production in sinusoidal endothelial cells (SECs). Here, we hypothesized that GIT1's tightly associated binding partner, β-PIX (p21-activated kinase-interacting exchange factor β, ARHGEF7) is specifically important in the regulation of eNOS activity. We examined β-PIX expression in normal rat liver by immunohistochemistry and explored β-PIX protein-protein interactions using immunoprecipitation and immunoblotting. The role of β-PIX in regulating eNOS enzymatic activity was studied in GIT1-deficient SECs. Finally, structural analysis of interaction sites in GIT1 and β-PIX required to regulate eNOS activity were mapped. β-PIX was expressed primarily in SECs in normal liver and was either absent or expressed at extremely low levels in other liver cells (stellate cells, Kupffer cells, and hepatocytes). β-PIX interacted with GIT1 and eNOS to form a trimolecular signaling module in normal SECs and was important in stimulating eNOS activity. Of note, GIT1-β-PIX interaction led to synergistic enhancement of eNOS activity, and β-PIX-driven increase in eNOS activity was GIT1 dependent. Disruption of β-PIX or GIT1 in normal SECs using β-PIX siRNA or GIT1-deficient SECs led to reduced eNOS activity. Finally, specific GIT1 domains [Spa2 homology domain (SHD) and synaptic localization domain (SLD), aa 331-596] and the β-PIX COOH terminal (aa 496-555) appeared to be critical in the regulation eNOS activity. The data indicate that β-PIX regulates eNOS phosphorylation and function in normal SECs and highlight the importance of the GIT1/β-PIX/eNOS trimolecular complex in normal liver SEC function.NEW & NOTEWORTHY β-PIX is a multidomain protein known to be a GIT1 binding partner. We report here that in the normal liver, the distribution and cellular localization of β-PIX are restricted largely to sinusoidal endothelial cells. Furthermore, β-PIX interacts with eNOS and GIT1 promotes eNOS activity and NO production and therefore exerts a novel posttranslational regulatory function on eNOS activity in sinusoidal endothelial cells. We also have identified specific molecular domains important in GIT1 and β-PIX's interaction with eNOS, which may represent novel therapeutic targets in the control of sinusoidal blood flow and intrahepatic resistance.
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Affiliation(s)
- Songling Liu
- Digestive Disease Research Center, Medical University of South Carolina, Charleston, South Carolina
| | - Richard T Premont
- Harrington Discovery Institute, University Hospitals Cleveland Medical Center, Cleveland, Ohio
- Institute for Transformative Molecular Medicine, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Ki-Hoon Park
- Digestive Disease Research Center, Medical University of South Carolina, Charleston, South Carolina
| | - Don C Rockey
- Digestive Disease Research Center, Medical University of South Carolina, Charleston, South Carolina
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10
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Moens U. Role of Signaling Pathways in the Viral Life Cycle 2.0. Int J Mol Sci 2022; 23:ijms23147857. [PMID: 35887205 PMCID: PMC9324909 DOI: 10.3390/ijms23147857] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 07/14/2022] [Indexed: 11/26/2022] Open
Affiliation(s)
- Ugo Moens
- Molecular Inflammation Research Group, Department of Medical Biology, Faculty of Health Sciences, University of Tromsø-The Arctic University of Norway, 9037 Tromsø, Norway
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11
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Cheng H, Guo P, Su T, Jiang C, Zhu Z, Wei W, Zhang L, Wang Q. G protein-coupled receptor kinase type 2 and β-arrestin2: Key players in immune cell functions and inflammation. Cell Signal 2022; 95:110337. [DOI: 10.1016/j.cellsig.2022.110337] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 04/15/2022] [Accepted: 04/15/2022] [Indexed: 02/07/2023]
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Johnstone EKM, Ayoub MA, Hertzman RJ, See HB, Abhayawardana RS, Seeber RM, Pfleger KDG. Novel Pharmacology Following Heteromerization of the Angiotensin II Type 2 Receptor and the Bradykinin Type 2 Receptor. Front Endocrinol (Lausanne) 2022; 13:848816. [PMID: 35721749 PMCID: PMC9204302 DOI: 10.3389/fendo.2022.848816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 03/21/2022] [Indexed: 01/18/2023] Open
Abstract
The angiotensin type 2 (AT2) receptor and the bradykinin type 2 (B2) receptor are G protein-coupled receptors (GPCRs) that have major roles in the cardiovascular system. The two receptors are known to functionally interact at various levels, and there is some evidence that the observed crosstalk may occur as a result of heteromerization. We investigated evidence for heteromerization of the AT2 receptor and the B2 receptor in HEK293FT cells using various bioluminescence resonance energy transfer (BRET)-proximity based assays, including the Receptor Heteromer Investigation Technology (Receptor-HIT) and the NanoBRET ligand-binding assay. The Receptor-HIT assay showed that Gαq, GRK2 and β-arrestin2 recruitment proximal to AT2 receptors only occurred upon B2 receptor coexpression and activation, all of which is indicative of AT2-B2 receptor heteromerization. Additionally, we also observed specific coupling of the B2 receptor with the Gαz protein, and this was found only in cells coexpressing both receptors and stimulated with bradykinin. The recruitment of Gαz, Gαq, GRK2 and β-arrestin2 was inhibited by B2 receptor but not AT2 receptor antagonism, indicating the importance of B2 receptor activation within AT2-B2 heteromers. The close proximity between the AT2 receptor and B2 receptor at the cell surface was also demonstrated with the NanoBRET ligand-binding assay. Together, our data demonstrate functional interaction between the AT2 receptor and B2 receptor in HEK293FT cells, resulting in novel pharmacology for both receptors with regard to Gαq/GRK2/β-arrestin2 recruitment (AT2 receptor) and Gαz protein coupling (B2 receptor). Our study has revealed a new mechanism for the enigmatic and poorly characterized AT2 receptor to be functionally active within cells, further illustrating the role of heteromerization in the diversity of GPCR pharmacology and signaling.
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Affiliation(s)
- Elizabeth K. M. Johnstone
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands, WA, Australia
- Australian Research Council Centre for Personalised Therapeutics Technologies, Perth, WA, Australia
- School of Biomedical Sciences, The University of Western Australia, Nedlands, WA, Australia
- *Correspondence: Elizabeth K. M. Johnstone, ; Kevin D. G. Pfleger,
| | - Mohammed Akli Ayoub
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands, WA, Australia
- Department of Biology, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Rebecca J. Hertzman
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands, WA, Australia
- School of Biomedical Sciences, The University of Western Australia, Nedlands, WA, Australia
| | - Heng B. See
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands, WA, Australia
- Australian Research Council Centre for Personalised Therapeutics Technologies, Perth, WA, Australia
| | - Rekhati S. Abhayawardana
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands, WA, Australia
- Australian Research Council Centre for Personalised Therapeutics Technologies, Perth, WA, Australia
| | - Ruth M. Seeber
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands, WA, Australia
- Australian Research Council Centre for Personalised Therapeutics Technologies, Perth, WA, Australia
| | - Kevin D. G. Pfleger
- Harry Perkins Institute of Medical Research and Centre for Medical Research, The University of Western Australia, Nedlands, WA, Australia
- Australian Research Council Centre for Personalised Therapeutics Technologies, Perth, WA, Australia
- Dimerix Limited, Nedlands, WA, Australia
- *Correspondence: Elizabeth K. M. Johnstone, ; Kevin D. G. Pfleger,
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Iwakiri Y, Trebicka J. Portal hypertension in cirrhosis: Pathophysiological mechanisms and therapy. JHEP Rep 2021; 3:100316. [PMID: 34337369 PMCID: PMC8318926 DOI: 10.1016/j.jhepr.2021.100316] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 04/19/2021] [Accepted: 05/12/2021] [Indexed: 12/14/2022] Open
Abstract
Portal hypertension, defined as increased pressure in the portal vein, develops as a consequence of increased intrahepatic vascular resistance due to the dysregulation of liver sinusoidal endothelial cells (LSECs) and hepatic stellate cells (HSCs), frequently arising from chronic liver diseases. Extrahepatic haemodynamic changes contribute to the aggravation of portal hypertension. The pathogenic complexity of portal hypertension and the unsuccessful translation of preclinical studies have impeded the development of effective therapeutics for patients with cirrhosis, while counteracting hepatic and extrahepatic mechanisms also pose a major obstacle to effective treatment. In this review article, we will discuss the following topics: i) cellular and molecular mechanisms of portal hypertension, focusing on dysregulation of LSECs, HSCs and hepatic microvascular thrombosis, as well as changes in the extrahepatic vasculature, since these are the major contributors to portal hypertension; ii) translational/clinical advances in our knowledge of portal hypertension; and iii) future directions.
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Key Words
- ACE2, angiogenesis-converting enzyme 2
- ACLF, acute-on-chronic liver failure
- AT1R, angiotensin II type I receptor
- CCL2, chemokine (C-C motif) ligand 2
- CCl4, carbon tetrachloride
- CLD, chronic liver disease
- CSPH, clinically significant portal hypertension
- Dll4, delta like canonical Notch ligand 4
- ECM, extracellular matrix
- EUS, endoscopic ultrasound
- FXR
- FXR, farnesoid X receptor
- HCC, hepatocellular carcinoma
- HRS, hepatorenal syndrome
- HSC
- HSCs, hepatic stellate cells
- HVPG, hepatic venous pressure gradient
- Hsp90, heat shock protein 90
- JAK2, Janus kinase 2
- KO, knockout
- LSEC
- LSEC, liver sinusoidal endothelial cells
- MLCP, myosin light-chain phosphatase
- NET, neutrophil extracellular trap
- NO
- NO, nitric oxide
- NSBB
- NSBBs, non-selective beta blockers
- PDE, phosphodiesterase
- PDGF, platelet-derived growth factor
- PIGF, placental growth factor
- PKG, cGMP-dependent protein kinase
- Rho-kinase
- TIPS
- TIPS, transjugular intrahepatic portosystemic shunt
- VCAM1, vascular cell adhesion molecule 1
- VEGF
- VEGF, vascular endothelial growth factor
- angiogenesis
- eNOS, endothelial nitric oxide synthase
- fibrosis
- liver stiffness
- statins
- β-Arr2, β-arrestin 2
- β1-AR, β1-adrenergic receptor
- β2-AR, β2-adrenergic receptor
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Affiliation(s)
- Yasuko Iwakiri
- Section of Digestive Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT, USA
| | - Jonel Trebicka
- Translational Hepatology, Department of Internal Medicine I, University Clinic Frankfurt, Frankfurt, Germany
- European Foundation for the Study of Chronic Liver Failure-EF Clif, Barcelona, Spain
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Arrb2 causes hepatic lipid metabolism disorder via AMPK pathway based on metabolomics in alcoholic fatty liver. Clin Sci (Lond) 2021; 135:1213-1232. [PMID: 33871024 DOI: 10.1042/cs20201363] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 04/09/2021] [Accepted: 04/19/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND AIMS Alcoholic fatty liver (AFL) is an early form of alcoholic liver disease (ALD) that usually manifests as lipid synthesis abnormalities in hepatocytes. β-arrestin2 (Arrb2) is involved in multiple biological processes. The present study aimed to explore the role of Arrb2 in the regulation of lipid metabolism in AFL and the underlying mechanism and identify potential targets for the treatment of AFL. METHODS The expression of Arrb2 was detected in liver tissues obtained from AFL patients and Gao-binge AFL model mice. In addition, we specifically knocked down Arrb2 in AFL mouse liver in vivo and used Arrb2-siRNA or pEX3-Arrb2 to silence or overexpress Arrb2 in AML-12 cells in vitro to explore the functional role and underlying regulatory mechanism of Arrb2 in AFL. Finally, we investigated whether Arrb2 could cause changes in hepatic lipid metabolites, thereby leading to dysregulation of lipid metabolism based on liquid chromatography-mass spectrometry (LC-MS) analysis. RESULTS Arrb2 was up-regulated in the livers of AFL patients and AFL mice. The in vivo and in vitro results confirmed that Arrb2 could induce lipid accumulation and metabolism disorders. Mechanistically, Arrb2 induced hepatic metabolism disorder via AMP-activated protein kinase (AMPK) pathway. The results of LC-MS analysis revealed that hepatic lipid metabolites with the most significant differences were primary bile acids. CONCLUSIONS Arrb2 induces hepatic lipid metabolism disorders via AMPK pathway in AFL. On one hand, Arrb2 increases fatty acid synthesis. On the other hand, Arrb2 could increase the cholesterol synthesis, thereby leading to the up-regulation of primary bile acid levels.
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Abstract
PURPOSE OF REVIEW Statins are a class of lipid lower medications used primarily in patients with high-risk cardiovascular disease. Since their development, statins have been considered to be harmful in patients with liver disease, and many of the prescribing information labels consider them to be contraindicated in patients with active liver disease. However, recent studies have shown the contrary, warranting further investigation and discussion. This review aims to describe the latest literature on the mechanism, safety profile and potential benefits of statins use on the natural history of chronic liver disease (CLD) progression and its complications. RECENT FINDINGS A number of recently published studies have added to the existing body of literature supporting the concept that statins are safe and likely to be beneficial for treating patients with CLD. Patients with CLD including hepatitis B virus infection, hepatitis C virus infection, nonalcoholic fatty liver disease and alcohol on statins have been shown to have a lower rate of decompensating events, lower incidence of hepatocellular cancer, a lower rate of infections, and increased survival. However, the majority of the available literature supporting statin use in patients with liver disease comes from retrospective observational studies with high potential for bias. SUMMARY Statins appear to be safe in patients with compensated cirrhosis, and evidence suggests that they may reduce fibrosis, even in patients with advanced fibrosis and cirrhosis. Further high-quality research on this topic is needed to fully delineate the effect of statins in patients with liver disease.
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Affiliation(s)
- Mohamad Kareem Marrache
- Digestive Disease Research Center, Medical University of South Carolina, Charleston, South Carolina, USA
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Ma TL, Zhou Y, Zhang CY, Gao ZA, Duan JX. The role and mechanism of β-arrestin2 in signal transduction. Life Sci 2021; 275:119364. [PMID: 33741415 DOI: 10.1016/j.lfs.2021.119364] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 03/02/2021] [Accepted: 03/10/2021] [Indexed: 02/06/2023]
Abstract
β-arrestin2 is a ubiquitously expressed scaffold protein localized on the cytoplasm and plasma membrane. It was originally found to bind to GPCRs, uncoupling G proteins and receptors' binding and inhibiting the signal transduction of the GPCRs. Further investigations have revealed that β-arrestin2 not only mediates the desensitization of GPCRs but also serves as a multifunctional scaffold to mediate receptor internalization, kinase activation, and regulation of various signaling pathways, such as TLR4/NF-κB, MAPK, Wnt, TGF-β, and AMPK/mTOR pathways. β-arrestin2 regulates cell invasion, migration, autophagy, angiogenesis, and anti-inflammatory effects by regulating various signaling pathways, which play a vital role in many physiological and pathological processes. This paper reviews the structure and function of β-arrestin2, the regulation of β-arrestin2 based signaling pathways. The role and mechanism of β-arrestin2 signaling have been delineated in sufficient detail. The prospect of regulating the expression and activity of β-arrestin2 in multisystem diseases holds substantial therapeutic promise.
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Affiliation(s)
- Tian-Liang Ma
- Department of Orthopedics, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China; Hunan Engineering Research Center of Biomedical Metal and Ceramic Impants, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China; Department of Physiology, School of Basic Medical Science, Central South University, Changsha, Hunan 410078, China
| | - Yong Zhou
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha, Hunan 410078, China; Department of Cardiology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China
| | - Chen-Yu Zhang
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha, Hunan 410078, China
| | - Zi-Ang Gao
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha, Hunan 410078, China
| | - Jia-Xi Duan
- Department of Pulmonary and Critical Care Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, China; Research Unit of Respiratory Disease, Central South University, Changsha, Hunan 410011, China.
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Taguchi K, Kaneko N, Okudaira K, Matsumoto T, Kobayashi T. GLP-1 modulates insulin-induced relaxation response through β-arrestin2 regulation in diabetic mice aortas. Acta Physiol (Oxf) 2021; 231:e13573. [PMID: 33098611 DOI: 10.1111/apha.13573] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 10/19/2020] [Accepted: 10/20/2020] [Indexed: 12/15/2022]
Abstract
AIMS Diabetes impairs insulin-induced endothelium-dependent relaxation by reducing nitric oxide (NO) production. GLP-1, an incretin hormone, has been shown to prevent the development of endothelial dysfunction. In this study, we hypothesized that GLP-1 would improve the impaired insulin-induced relaxation response in diabetic mice. We also examined the underlying mechanisms. METHODS Using aortic rings from ob/ob mice, an animal model of obesity and type 2 diabetes, and from lean mice, vascular relaxation responses and protein expressions were evaluated using insulin, GLP-1, and pathway-specific inhibitors to elucidate the mechanisms of response. In parallel experiments, β-arrestin2 siRNA-transfected aortas were treated with GLP-1 to evaluate its effects on aortic response pathways. RESULTS When compared to that of untreated ob/ob aortas, GLP-1 increased insulin-induced vasorelaxation and NO production. AMPK inhibition did not alter this vasorelaxation in both GLP-1-treated lean and ob/ob aortas, while Akt inhibition reduced vasorelaxation in both groups, and co-treatment with GLP-1 and insulin caused Akt/eNOS activation. Additionally, GLP-1 decreased GRK2 activity and enhanced β-arrestin2 translocation from the cytosol to membrane in ob/ob aortas. β-Arrestin2 siRNA decreased insulin-induced relaxation both in lean aortas and GLP-1-treated ob/ob aortas. CONCLUSIONS We demonstrated that insulin-induced relaxation is dependent on β-arrestin2 translocation and Akt activation via GLP-1-stimulated GRK2 inactivation in ob/ob aortas. We showed a novel cross-talk between GLP-1-responsive β-arrestin2 and insulin signalling in diabetic aortas.
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Affiliation(s)
- Kumiko Taguchi
- Department of Physiology and Morphology Institute of Medicinal Chemistry Hoshi University Tokyo Japan
| | - Nozomu Kaneko
- Department of Physiology and Morphology Institute of Medicinal Chemistry Hoshi University Tokyo Japan
| | - Kanami Okudaira
- Department of Physiology and Morphology Institute of Medicinal Chemistry Hoshi University Tokyo Japan
| | - Takayuki Matsumoto
- Department of Physiology and Morphology Institute of Medicinal Chemistry Hoshi University Tokyo Japan
| | - Tsuneo Kobayashi
- Department of Physiology and Morphology Institute of Medicinal Chemistry Hoshi University Tokyo Japan
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PPARs in liver physiology. Biochim Biophys Acta Mol Basis Dis 2021; 1867:166097. [PMID: 33524529 DOI: 10.1016/j.bbadis.2021.166097] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 02/07/2023]
Abstract
Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors and transcriptional modulators with crucial functions in hepatic and whole-body energy homeostasis. Besides their well-documented roles in lipid and glucose metabolism, emerging evidence also implicate PPARs in the control of other processes such as inflammatory responses. Recent technological advances, such as single-cell RNA sequencing, have allowed to unravel an unexpected complexity in the regulation of PPAR expression, activity and downstream signaling. Here we provide an overview of the latest advances in the study of PPARs in liver physiology, with a specific focus on formerly neglected aspects of PPAR regulation, such as tissular zonation, cellular heterogeneity, circadian rhythms, sexual dimorphism and species-specific features.
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Lee C, Viswanathan G, Choi I, Jassal C, Kohlmann T, Rajagopal S. Beta-Arrestins and Receptor Signaling in the Vascular Endothelium. Biomolecules 2020; 11:biom11010009. [PMID: 33374806 PMCID: PMC7824595 DOI: 10.3390/biom11010009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 12/13/2020] [Accepted: 12/19/2020] [Indexed: 12/17/2022] Open
Abstract
The vascular endothelium is the innermost layer of blood vessels and is a key regulator of vascular tone. Endothelial function is controlled by receptor signaling through G protein-coupled receptors, receptor tyrosine kinases and receptor serine-threonine kinases. The β-arrestins, multifunctional adapter proteins, have the potential to regulate all of these receptor families, although it is unclear as to whether they serve to integrate signaling across all of these different axes. Notably, the β-arrestins have been shown to regulate signaling by a number of receptors important in endothelial function, such as chemokine receptors and receptors for vasoactive substances such as angiotensin II, endothelin-1 and prostaglandins. β-arrestin-mediated signaling pathways have been shown to play central roles in pathways that control vasodilation, cell proliferation, migration, and immune function. At this time, the physiological impact of this signaling has not been studied in detail, but a deeper understanding of it could lead to the development of novel therapies for the treatment of vascular disease.
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Affiliation(s)
- Claudia Lee
- Department of Biochemistry, School of Medicine, Duke University, Durham, NC 27710, USA;
| | - Gayathri Viswanathan
- Medical Center, Department of Medicine, Division of Cardiology, Duke University, Durham, NC 27710, USA; (G.V.); (I.C.)
| | - Issac Choi
- Medical Center, Department of Medicine, Division of Cardiology, Duke University, Durham, NC 27710, USA; (G.V.); (I.C.)
| | - Chanpreet Jassal
- College of Arts and Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA;
| | - Taylor Kohlmann
- Trinity College of Arts and Sciences, Duke University, Durham, NC 27708, USA;
| | - Sudarshan Rajagopal
- Department of Biochemistry, School of Medicine, Duke University, Durham, NC 27710, USA;
- Medical Center, Department of Medicine, Division of Cardiology, Duke University, Durham, NC 27710, USA; (G.V.); (I.C.)
- Correspondence:
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21
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Liu S, Luttrell LM, Premont RT, Rockey DC. Reply to Schierwagen et al.: β-Arrestins in liver disease. Proc Natl Acad Sci U S A 2020; 117:27085-27086. [PMID: 33144523 PMCID: PMC7959548 DOI: 10.1073/pnas.2014931117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Songling Liu
- Division of Gastroenterology and Hepatology, Medical University of South Carolina, Charleston, SC 29425
| | - Louis M Luttrell
- Division of Endocrinology, Diabetes & Metabolic Diseases, Medical University of South Carolina, Charleston, SC 29425
| | - Richard T Premont
- Harrington Discovery Institute, University Hospitals Cleveland Medical Center, Cleveland, OH 44106
- Institute for Transformative Molecular Medicine, Case Western Reserve University School of Medicine, Cleveland, OH 44106
| | - Don C Rockey
- Digestive Disease Research Center, Medical University of South Carolina, Charleston, SC 29425
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