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Taki S, Boron WF, Moss FJ. Novel RPTPγ and RPTPζ splice variants from mixed neuron-astrocyte hippocampal cultures as well as from the hippocampi of newborn and adult mice. Front Physiol 2024; 15:1406448. [PMID: 38952869 PMCID: PMC11215419 DOI: 10.3389/fphys.2024.1406448] [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: 03/25/2024] [Accepted: 05/06/2024] [Indexed: 07/03/2024] Open
Abstract
Receptor protein tyrosine phosphatases γ and ζ (RPTPγ and RPTPζ) are transmembrane signaling proteins with extracellular carbonic anhydrase-like domains that play vital roles in the development and functioning of the central nervous system (CNS) and are implicated in tumor suppression, neurodegeneration, and sensing of extracellular [CO2] and [HCO3 -]. RPTPγ expresses throughout the body, whereas RPTPζ preferentially expresses in the CNS. Here, we investigate differential RPTPγ-RPTPζ expression in three sources derived from a wild-type laboratory strain of C57BL/6 mice: (a) mixed neuron-astrocyte hippocampal (HC) cultures 14 days post isolation from P0-P2 pups; (b) P0-P2 pup hippocampi; and (c) 9- to 12-week-old adult hippocampi. Regarding RPTPγ, we detect the Ptprg variant-1 (V1) transcript, representing canonical exons 1-30. Moreover, we newly validate the hypothetical assembly [XM_006517956] (propose name, Ptprg-V3), which lacks exon 14. Both transcripts are in all three HC sources. Regarding RPTPζ, we confirm the expression of Ptprz1-V1, detecting it in pups and adults but not in cultures, and Ptprz1-V3 through Ptprz1-V7 in all three preparations. We newly validate hypothetical assemblies Ptprz1-X1 (in cultures and pups), Ptprz1-X2 (in all three), and Ptprz1-X5 (in pups and adults) and propose to re-designate them as Ptprz1-V0, Ptprz1-V2, and Ptprz1-V8, respectively. The diversity of RPTPγ and RPTPζ splice variants likely corresponds to distinct signaling functions, in different cellular compartments, during development vs later life. In contrast to previous studies that report divergent RPTPγ and RPTPζ protein expressions in neurons and sometimes in the glia, we observe that RPTPγ and RPTPζ co-express in the somata and processes of almost all HC neurons but not in astrocytes, in all three HC preparations.
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Affiliation(s)
- Sara Taki
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Walter F. Boron
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, United States
- Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, United States
- Department of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, OH, United States
| | - Fraser J. Moss
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, United States
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Boedtkjer E, Ara T. Strengthening the basics: acids and bases influence vascular structure and function, tissue perfusion, blood pressure, and human cardiovascular disease. Pflugers Arch 2024; 476:623-637. [PMID: 38383822 DOI: 10.1007/s00424-024-02926-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/08/2024] [Accepted: 02/09/2024] [Indexed: 02/23/2024]
Abstract
Acids and their conjugate bases accumulate in or dissipate from the interstitial space when tissue perfusion does not match the metabolic demand. Extracellular acidosis dilates most arterial beds, but associated acid-base disturbances-e.g., intracellular acidification and decreases in HCO3- concentration-can also elicit pro-contractile influences that diminish vasodilation and even dominate in some vascular beds to cause vasoconstriction. The ensemble activities of the acid-base-sensitive reactions in vascular smooth muscle and endothelial cells optimize vascular resistance for blood pressure control and direct the perfusion towards active tissue. In this review, we describe the mechanisms of intracellular pH regulation in the vascular wall and discuss how vascular smooth muscle and endothelial cells sense acid-base disturbances. We further deliberate on the functional effects of local acid-base disturbances and their integrated cardiovascular consequences under physiological and pathophysiological conditions. Finally, we address how mutations and polymorphisms in the molecular machinery that regulates pH locally and senses acid-base disturbances in the vascular wall can result in cardiovascular disease. Based on the emerging molecular insight, we propose that targeting local pH-dependent effectors-rather than systemic acid-base disturbances-has therapeutic potential to interfere with the progression and reduce the severity of cardiovascular disease.
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Affiliation(s)
- Ebbe Boedtkjer
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergs Gade 10, DK-8000, Aarhus, Denmark.
| | - Tarannum Ara
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergs Gade 10, DK-8000, Aarhus, Denmark
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3
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Zhang H, Chang Y, Li Y, Wei J, Ma X, Zhou W, Zang X, Jin T, Wu S. Effects of CASZ1, WNT2B and PTPRG SNPs on stroke susceptibility in the Chinese Han population. Eur J Clin Invest 2024; 54:e14144. [PMID: 38059696 DOI: 10.1111/eci.14144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 10/20/2023] [Accepted: 11/19/2023] [Indexed: 12/08/2023]
Abstract
BACKGROUND Stroke is an important cause of death and disability worldwide, ranking second in the cause of death, and it is thought to be related to genetic factors. The purpose of our study is to investigate the association between CASZ1, WNT2B and PTPRG single nucleotide polymorphisms (SNPs) and stroke risk in the Chinese population. METHODS We recruited 1418 volunteers, comprised of 710 stroke cases and 708 controls in this study. We used MassARRAY iPLEX GOLD method to genotype the three SNPs on CASZ1, WNT2B and PTPRG. Logistic regression was used to analyse the association between these SNPs and stroke, and odds ratios (ORs) and 95% confidence intervals (CIs) were then calculated. What's more, the interactions among SNPs were predicted by multi-factor dimensionality reduction (MDR) analysis. RESULTS This research demonstrated that CASZ1 rs880315 and PTPRG rs704341 were associated with reduced stroke susceptibility. More precisely, CASZ1 rs880315 was associated with reduced stroke susceptibility in people aged ≤64 years and women. PTPRG rs704341 was associated with reduced stroke susceptibility in people aged >64 years, women, non-smokers and non-drinkers. Conversely, WNT2B rs12037987 was related to elevated stroke susceptibility in people aged >64 years, women and non-smokers. In addition, CASZ1 rs880315, WNT2B rs12037987 and PTPRG rs704341 had a strong redundancy relationship. CONCLUSION Our study concludes that CASZ1 rs880315, WNT2B rs12037987 and PTPRG rs704341 are associated with stroke, and the study provides a basis for assessing genetic variants associated with stroke risk in the Han Chinese population.
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Affiliation(s)
- Huan Zhang
- College of Life Science, Northwest University, Xi'an, Shaanxi, China
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), School of Life Sciences, Ministry of Education, Northwest University, Xi'an, Shaanxi, China
- Provincial Key Laboratory of Biotechnology of Shaanxi Province, Northwest University, Xi'an, Shaanxi, China
- Department of Neurology, The First Hospital of Xi'an, The First Affiliated Hospital of Northwest University, Xi'an, Shaanxi, China
| | - Yanting Chang
- College of Life Science, Northwest University, Xi'an, Shaanxi, China
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), School of Life Sciences, Ministry of Education, Northwest University, Xi'an, Shaanxi, China
- Provincial Key Laboratory of Biotechnology of Shaanxi Province, Northwest University, Xi'an, Shaanxi, China
- Department of Neurology, The First Hospital of Xi'an, The First Affiliated Hospital of Northwest University, Xi'an, Shaanxi, China
| | - Yujie Li
- College of Life Science, Northwest University, Xi'an, Shaanxi, China
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), School of Life Sciences, Ministry of Education, Northwest University, Xi'an, Shaanxi, China
- Provincial Key Laboratory of Biotechnology of Shaanxi Province, Northwest University, Xi'an, Shaanxi, China
| | - Jie Wei
- College of Life Science, Northwest University, Xi'an, Shaanxi, China
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), School of Life Sciences, Ministry of Education, Northwest University, Xi'an, Shaanxi, China
- Provincial Key Laboratory of Biotechnology of Shaanxi Province, Northwest University, Xi'an, Shaanxi, China
| | - Xiaoya Ma
- College of Life Science, Northwest University, Xi'an, Shaanxi, China
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), School of Life Sciences, Ministry of Education, Northwest University, Xi'an, Shaanxi, China
- Provincial Key Laboratory of Biotechnology of Shaanxi Province, Northwest University, Xi'an, Shaanxi, China
| | - Wenqian Zhou
- College of Life Science, Northwest University, Xi'an, Shaanxi, China
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), School of Life Sciences, Ministry of Education, Northwest University, Xi'an, Shaanxi, China
- Provincial Key Laboratory of Biotechnology of Shaanxi Province, Northwest University, Xi'an, Shaanxi, China
| | - Xufeng Zang
- College of Life Science, Northwest University, Xi'an, Shaanxi, China
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), School of Life Sciences, Ministry of Education, Northwest University, Xi'an, Shaanxi, China
- Provincial Key Laboratory of Biotechnology of Shaanxi Province, Northwest University, Xi'an, Shaanxi, China
| | - Tianbo Jin
- College of Life Science, Northwest University, Xi'an, Shaanxi, China
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), School of Life Sciences, Ministry of Education, Northwest University, Xi'an, Shaanxi, China
- Provincial Key Laboratory of Biotechnology of Shaanxi Province, Northwest University, Xi'an, Shaanxi, China
| | - Songdi Wu
- College of Life Science, Northwest University, Xi'an, Shaanxi, China
- Department of Neurology, The First Hospital of Xi'an, The First Affiliated Hospital of Northwest University, Xi'an, Shaanxi, China
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4
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Du W, Yang J, Lou Y, You J, Wang Q. Relationship between baseline bicarbonate and 30-day mortality in patients with non-traumatic subarachnoid hemorrhage. Front Neurol 2024; 14:1310327. [PMID: 38234976 PMCID: PMC10793108 DOI: 10.3389/fneur.2023.1310327] [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: 10/09/2023] [Accepted: 12/13/2023] [Indexed: 01/19/2024] Open
Abstract
Objective This study aimed to explore the relationship between baseline bicarbonate levels and 30-day mortality in individuals with non-traumatic subarachnoid hemorrhage (SAH). Methods Patients with non-traumatic SAH were chosen from the Medical Information Mart for Intensive Care (MIMIC)-IV database. The relationship between baseline bicarbonate and 30-day mortality was examined using Cox regression models. Restricted cubic splines were used to test the hypothesis that there was an association between bicarbonate and mortality. With the use of Kaplan-Meier survival curve analysis, we looked deeper into the validity of these correlations. To find subgroups with differences, interaction tests were utilized. Results This retrospective cohort study consisted of 521 participants in total. Bicarbonate had a negative association with death at 30 days (HR = 0.93, 95%CI: 0.88-0.98, p = 0.004). Next, we divided bicarbonate into quartile groups. In comparison to the reference group Q1 (20 mEq/L), groups Q3 (23-25 mEq/L) and Q4 (26 mEq/L) had adjusted HR values of 0.47 (95%CI: 0.27-0.82, p = 0.007) and 0.56 (95%CI: 0.31-0.99, p = 0.047). No definite conclusions can be derived from this study, since there is no obvious curve link between baseline bicarbonate and 30-day mortality. Patients' 30-day mortality increased statistically significantly (p < 0.001, K-M analysis) in patients with low bicarbonate levels. The relationship between bicarbonate and 30-day mortality remained consistent in the stratified analysis, with no observed interactions. Conclusion Finally, 30-day mortality was negatively associated with baseline bicarbonate levels. Patients with non-traumatic SAH are more at risk of mortality if their bicarbonate levels are low.
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Affiliation(s)
- Wenyuan Du
- Department of Neurology, Shijiazhuang Traditional Chinese Medicine Hospital, Shijiazhuang, Hebei, China
| | - Jingmian Yang
- Department of Neurology, Shijiazhuang Traditional Chinese Medicine Hospital, Shijiazhuang, Hebei, China
| | - Yanfang Lou
- Department of Neurology, Shijiazhuang Traditional Chinese Medicine Hospital, Shijiazhuang, Hebei, China
| | - Jiahua You
- Department of Neurology, Shijiazhuang Traditional Chinese Medicine Hospital, Shijiazhuang, Hebei, China
| | - Qiang Wang
- Department of Cardiology, Shijiazhuang Traditional Chinese Medicine Hospital, Shijiazhuang, Hebei, China
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5
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Homilius C, Seefeldt JM, Axelsen JS, Pedersen TM, Sørensen TM, Nielsen R, Wiggers H, Hansen J, Matchkov VV, Bøtker HE, Boedtkjer E. Ketone body 3-hydroxybutyrate elevates cardiac output through peripheral vasorelaxation and enhanced cardiac contractility. Basic Res Cardiol 2023; 118:37. [PMID: 37688627 PMCID: PMC10492777 DOI: 10.1007/s00395-023-01008-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 08/21/2023] [Accepted: 09/01/2023] [Indexed: 09/11/2023]
Abstract
The ketone body 3-hydroxybutyrate (3-OHB) increases cardiac output and myocardial perfusion without affecting blood pressure in humans, but the cardiovascular sites of action remain obscure. Here, we test the hypothesis in rats that 3-OHB acts directly on the heart to increase cardiac contractility and directly on blood vessels to lower systemic vascular resistance. We investigate effects of 3-OHB on (a) in vivo hemodynamics using echocardiography and invasive blood pressure measurements, (b) isolated perfused hearts in Langendorff systems, and (c) isolated arteries and veins in isometric myographs. We compare Na-3-OHB to equimolar NaCl added to physiological buffers or injection solutions. At plasma concentrations of 2-4 mM in vivo, 3-OHB increases cardiac output (by 28.3±7.8%), stroke volume (by 22.4±6.0%), left ventricular ejection fraction (by 13.3±4.6%), and arterial dP/dtmax (by 31.9±11.2%) and lowers systemic vascular resistance (by 30.6±11.2%) without substantially affecting heart rate or blood pressure. Applied to isolated perfused hearts at 3-10 mM, 3-OHB increases left ventricular developed pressure by up to 26.3±7.4 mmHg and coronary perfusion by up to 20.2±9.5%. Beginning at 1-3 mM, 3-OHB relaxes isolated coronary (EC50=12.4 mM), cerebral, femoral, mesenteric, and renal arteries as well as brachial, femoral, and mesenteric veins by up to 60% of pre-contraction within the pathophysiological concentration range. Of the two enantiomers that constitute racemic 3-OHB, D-3-OHB dominates endogenously; but tested separately, the enantiomers induce similar vasorelaxation. We conclude that increased cardiac contractility and generalized systemic vasorelaxation can explain the elevated cardiac output during 3-OHB administration. These actions strengthen the therapeutic rationale for 3-OHB in heart failure management.
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Affiliation(s)
- Casper Homilius
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergs Gade 10, 8000, Aarhus, Denmark
| | - Jacob Marthinsen Seefeldt
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Julie Sørensen Axelsen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Tina Myhre Pedersen
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergs Gade 10, 8000, Aarhus, Denmark
| | - Trine Monberg Sørensen
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergs Gade 10, 8000, Aarhus, Denmark
| | - Roni Nielsen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Henrik Wiggers
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Jakob Hansen
- Department of Forensic Medicine, Aarhus University, Aarhus, Denmark
| | - Vladimir V Matchkov
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergs Gade 10, 8000, Aarhus, Denmark
| | - Hans Erik Bøtker
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Ebbe Boedtkjer
- Department of Biomedicine, Aarhus University, Hoegh-Guldbergs Gade 10, 8000, Aarhus, Denmark.
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6
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Nielsen R, Christensen KH, Gopalasingam N, Berg‐Hansen K, Seefeldt J, Homilius C, Boedtkjer E, Andersen MJ, Wiggers H, Møller N, Bøtker HE, Mellemkjær S. Hemodynamic Effects of Ketone Bodies in Patients With Pulmonary Hypertension. J Am Heart Assoc 2023; 12:e028232. [PMID: 37183871 PMCID: PMC10227291 DOI: 10.1161/jaha.122.028232] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 04/10/2023] [Indexed: 05/16/2023]
Abstract
Background Pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) are debilitating diseases with a high mortality. Despite emerging treatments, pulmonary vascular resistance frequently remains elevated. However, the ketone body 3-hydroxybutyrate (3-OHB) may reduce pulmonary vascular resistance in these patients. Hence, the aim was to assess the hemodynamic effects of 3-OHB in patients with PAH or CTEPH. Methods and Results We enrolled patients with PAH (n=10) or CTEPH (n=10) and residual pulmonary hypertension. They received 3-OHB infusion and placebo (saline) for 2 hours in a randomized crossover study. Invasive hemodynamic and echocardiography measurements were performed. Furthermore, we investigated the effects of 3-OHB on the right ventricle of isolated hearts and isolated pulmonary arteries from Sprague-Dawley rats. Ketone body infusion increased circulating 3-OHB levels from 0.5±0.5 to 3.4±0.7 mmol/L (P<0.001). Cardiac output improved by 1.2±0.1 L/min (27±3%, P<0.001), and right ventricular annular systolic velocity increased by 1.4±0.4 cm/s (13±4%, P=0.002). Pulmonary vascular resistance decreased by 1.3±0.3 Wood units (18%±4%, P<0.001) with no significant difference in response between patients with PAH and CTEPH. In the rat studies, 3-OHB administration was associated with decreased pulmonary arterial tension compared with saline administration (maximal relative tension difference: 12±2%, P<0.001) and had no effect on right ventricular systolic pressures (P=0.63), whereas pressures rose at a slower pace (dP/dtmax, P=0.02). Conclusions In patients with PAH or CTEPH, ketone body infusion improves cardiac output and decreases pulmonary vascular resistance. Experimental rat studies support that ketone bodies relax pulmonary arteries. Long-term studies are warranted to assess the clinical role of hyperketonemia. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04615754.
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Affiliation(s)
- Roni Nielsen
- Department of CardiologyAarhus University HospitalAarhusDenmark
- Department of Clinical Medicine, Faculty of HealthAarhus UniversityAarhusDenmark
| | | | - Nigopan Gopalasingam
- Department of Clinical Medicine, Faculty of HealthAarhus UniversityAarhusDenmark
| | | | - Jacob Seefeldt
- Department of Clinical Medicine, Faculty of HealthAarhus UniversityAarhusDenmark
| | - Casper Homilius
- Department of Biomedicine, Faculty of HealthAarhus UniversityAarhusDenmark
| | - Ebbe Boedtkjer
- Department of Biomedicine, Faculty of HealthAarhus UniversityAarhusDenmark
| | | | - Henrik Wiggers
- Department of CardiologyAarhus University HospitalAarhusDenmark
- Department of Clinical Medicine, Faculty of HealthAarhus UniversityAarhusDenmark
| | - Niels Møller
- Medical/Steno Aarhus Research LaboratoryAarhus UniversityAarhusDenmark
| | - Hans Erik Bøtker
- Department of Biomedicine, Faculty of HealthAarhus UniversityAarhusDenmark
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Rajanathan R, Pedersen TM, Guldbrandsen HO, Olesen LF, Thomsen MB, Bøtker HE, Matchkov VV. Augmented Ouabain-Induced Vascular Response Reduces Cardiac Efficiency in Mice with Migraine-Associated Mutation in the Na +, K +-ATPase α 2-Isoform. Biomedicines 2023; 11:biomedicines11020344. [PMID: 36830881 PMCID: PMC9953359 DOI: 10.3390/biomedicines11020344] [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: 12/13/2022] [Revised: 01/22/2023] [Accepted: 01/23/2023] [Indexed: 01/27/2023] Open
Abstract
Heterozygous mice (α2+/G301R mice) for the migraine-associated mutation (G301R) in the Na+,K+-ATPase α2-isoform have decreased expression of cardiovascular α2-isoform. The α2+/G301R mice exhibit a pro-contractile vascular phenotype associated with decreased left ventricular ejection fraction. However, the integrated functional cardiovascular consequences of this phenotype remain to be addressed in vivo. We hypothesized that the vascular response to α2-isoform-specific inhibition of the Na+,K+-ATPase by ouabain is augmented in α2+/G301R mice leading to reduced cardiac efficiency. Thus, we aimed to assess the functional contribution of the α2-isoform to in vivo cardiovascular function of wild-type (WT) and α2+/G301R mice. Blood pressure, stroke volume, heart rate, total peripheral resistance, arterial dP/dt, and systolic time intervals were assessed in anesthetized WT and α2+/G301R mice. To address rate-dependent cardiac changes, cardiovascular variables were compared before and after intraperitoneal injection of ouabain (1.5 mg/kg) or vehicle during atrial pacing. The α2+/G301R mice showed an enhanced ouabain-induced increase in total peripheral resistance associated with reduced efficiency of systolic development compared to WT. When the hearts were paced, ouabain reduced stroke volume in α2+/G301R mice. In conclusion, the ouabain-induced vascular response was augmented in α2+/G301R mice with consequent suppression of cardiac function.
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Affiliation(s)
- Rajkumar Rajanathan
- Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark
- Correspondence:
| | | | | | | | - Morten B. Thomsen
- Department of Biomedical Sciences, University of Copenhagen, 1165 Copenhagen, Denmark
| | - Hans Erik Bøtker
- Department of Cardiology, Aarhus University Hospital, 8000 Aarhus, Denmark
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8
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Hendriks WJAJ, van Cruchten RTP, Pulido R. Hereditable variants of classical protein tyrosine phosphatase genes: Will they prove innocent or guilty? Front Cell Dev Biol 2023; 10:1051311. [PMID: 36755664 PMCID: PMC9900141 DOI: 10.3389/fcell.2022.1051311] [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: 09/22/2022] [Accepted: 12/28/2022] [Indexed: 01/24/2023] Open
Abstract
Protein tyrosine phosphatases, together with protein tyrosine kinases, control many molecular signaling steps that control life at cellular and organismal levels. Impairing alterations in the genes encoding the involved proteins is expected to profoundly affect the quality of life-if compatible with life at all. Here, we review the current knowledge on the effects of germline variants that have been reported for genes encoding a subset of the protein tyrosine phosphatase superfamily; that of the thirty seven classical members. The conclusion must be that the newest genome research tools produced an avalanche of data that suggest 'guilt by association' for individual genes to specific disorders. Future research should face the challenge to investigate these accusations thoroughly and convincingly, to reach a mature genotype-phenotype map for this intriguing protein family.
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Affiliation(s)
- Wiljan J. A. J. Hendriks
- Department of Cell Biology, Radboud University Medical Centre, Nijmegen, The Netherlands,*Correspondence: Wiljan J. A. J. Hendriks,
| | | | - Rafael Pulido
- Biomarkers in Cancer Unit, Biocruces Bizkaia Health Research Institute, Barakaldo, Spain,Ikerbasque, Basque Foundation for Science, Bilbao, Spain
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9
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Sloth RA, Axelsen TV, Espejo MS, Toft NJ, Voss NCS, Burton M, Thomassen M, Vahl P, Boedtkjer E. Loss of RPTPγ primes breast tissue for acid extrusion, promotes malignant transformation and results in early tumour recurrence and shortened survival. Br J Cancer 2022; 127:1226-1238. [PMID: 35821297 DOI: 10.1038/s41416-022-01911-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 06/22/2022] [Accepted: 06/29/2022] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND While cellular metabolism and acidic waste handling accelerate during breast carcinogenesis, temporal patterns of acid-base regulation and underlying molecular mechanisms responding to the tumour microenvironment remain unclear. METHODS We explore data from human cohorts and experimentally investigate transgenic mice to evaluate the putative extracellular HCO3--sensor Receptor Protein Tyrosine Phosphatase (RPTP)γ during breast carcinogenesis. RESULTS RPTPγ expression declines during human breast carcinogenesis and particularly in high-malignancy grade breast cancer. Low RPTPγ expression associates with poor prognosis in women with Luminal A or Basal-like breast cancer. RPTPγ knockout in mice favours premalignant changes in macroscopically normal breast tissue, accelerates primary breast cancer development, promotes malignant breast cancer histopathologies, and shortens recurrence-free survival. In RPTPγ knockout mice, expression of Na+,HCO3--cotransporter NBCn1-a breast cancer susceptibility protein-is upregulated in normal breast tissue but, contrary to wild-type mice, shows no further increase during breast carcinogenesis. Associated augmentation of Na+,HCO3--cotransport in normal breast tissue from RPTPγ knockout mice elevates steady-state intracellular pH, which has known pro-proliferative effects. CONCLUSIONS Loss of RPTPγ accelerates cellular net acid extrusion and elevates NBCn1 expression in breast tissue. As these effects precede neoplastic manifestations in histopathology, we propose that RPTPγ-dependent enhancement of Na+,HCO3--cotransport primes breast tissue for cancer development.
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Affiliation(s)
- Rasmus A Sloth
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Trine V Axelsen
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | - Nicolai J Toft
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Ninna C S Voss
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Mark Burton
- Department of Clinical Genetics, University of Southern Denmark, Odense, Denmark.,Clinical Genome Center, University and Region of Southern Denmark, Odense, Denmark.,Department of Clinical Medicine, University of Southern Denmark, Odense, Denmark
| | - Mads Thomassen
- Department of Clinical Genetics, University of Southern Denmark, Odense, Denmark.,Clinical Genome Center, University and Region of Southern Denmark, Odense, Denmark
| | - Pernille Vahl
- Department of Pathology, Aarhus University Hospital, Aarhus, Denmark
| | - Ebbe Boedtkjer
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.
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10
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Affiliation(s)
- Ebbe Boedtkjer
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Christian Aalkjaer
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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11
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Friend or foe? Unraveling the complex roles of protein tyrosine phosphatases in cardiac disease and development. Cell Signal 2022; 93:110297. [PMID: 35259455 PMCID: PMC9038168 DOI: 10.1016/j.cellsig.2022.110297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 02/14/2022] [Accepted: 02/27/2022] [Indexed: 11/21/2022]
Abstract
Regulation of protein tyrosine phosphorylation is critical for most, if not all, fundamental cellular processes. However, we still do not fully understand the complex and tissue-specific roles of protein tyrosine phosphatases in the normal heart or in cardiac pathology. This review compares and contrasts the various roles of protein tyrosine phosphatases known to date in the context of cardiac disease and development. In particular, it will be considered how specific protein tyrosine phosphatases control cardiac hypertrophy and cardiomyocyte contractility, how protein tyrosine phosphatases contribute to or ameliorate injury induced by ischaemia / reperfusion or hypoxia / reoxygenation, and how protein tyrosine phosphatases are involved in normal heart development and congenital heart disease. This review delves into the newest developments and current challenges in the field, and highlights knowledge gaps and emerging opportunities for future research.
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Rajanathan R, Pedersen TM, Thomsen MB, Botker HE, Matchkov VV. Phenylephrine-Induced Cardiovascular Changes in the Anesthetized Mouse: An Integrated Assessment of in vivo Hemodynamics Under Conditions of Controlled Heart Rate. Front Physiol 2022; 13:831724. [PMID: 35250634 PMCID: PMC8891648 DOI: 10.3389/fphys.2022.831724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 01/27/2022] [Indexed: 11/13/2022] Open
Abstract
Objective Investigating the cardiovascular system is challenging due to its complex regulation by humoral and neuronal factors. Despite this complexity, many existing research methods are limited to the assessment of a few parameters leading to an incomplete characterization of cardiovascular function. Thus, we aim to establish a murine in vivo model for integrated assessment of the cardiovascular system under conditions of controlled heart rate. Utilizing this model, we assessed blood pressure, cardiac output, stroke volume, total peripheral resistance, and electrocardiogram (ECG). Hypothesis We hypothesize that (i) our in vivo model can be utilized to investigate cardiac and vascular responses to pharmacological intervention with the α1-agonist phenylephrine, and (ii) we can study cardiovascular function during artificial pacing of the heart, modulating cardiac function without a direct vascular effect. Methods We included 12 mice that were randomly assigned to either vehicle or phenylephrine intervention through intraperitoneal administration. Mice were anesthetized with isoflurane and intubated endotracheally for mechanical ventilation. We measured blood pressure via a solid-state catheter in the aortic arch, blood flow via a probe on the ascending aorta, and ECG from needle electrodes on the extremities. Right atrium was electrically paced at a frequency ranging from 10 to 11.3 Hz before and after either vehicle or phenylephrine administration. Results Phenylephrine significantly increased blood pressure, stroke volume, and total peripheral resistance compared to the vehicle group. Moreover, heart rate was significantly decreased following phenylephrine administration. Pacing significantly decreased stroke volume and cardiac output both prior to and after drug administration. However, phenylephrine-induced changes in blood pressure and total peripheral resistance were maintained with increasing pacing frequencies compared to the vehicle group. Total peripheral resistance was not significantly altered with increasing pacing frequencies suggesting that the effect of phenylephrine is primarily of vascular origin. Conclusion In conclusion, this in vivo murine model is capable of distinguishing between changes in peripheral vascular and cardiac functions. This study underlines the primary effect of phenylephrine on vascular function with secondary changes to cardiac function. Hence, this in vivo model is useful for the integrated assessment of the cardiovascular system.
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Affiliation(s)
- Rajkumar Rajanathan
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- *Correspondence: Rajkumar Rajanathan,
| | | | - Morten B. Thomsen
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hans Erik Botker
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
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Boni C, Sorio C. The Role of the Tumor Suppressor Gene Protein Tyrosine Phosphatase Gamma in Cancer. Front Cell Dev Biol 2022; 9:768969. [PMID: 35071225 PMCID: PMC8766859 DOI: 10.3389/fcell.2021.768969] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 12/16/2021] [Indexed: 12/31/2022] Open
Abstract
Members of the Protein Tyrosine Phosphatase (PTPs) family are associated with growth regulation and cancer development. Acting as natural counterpart of tyrosine kinases (TKs), mainly involved in crucial signaling pathways such as regulation of cell cycle, proliferation, invasion and angiogenesis, they represent key parts of complex physiological homeostatic mechanisms. Protein tyrosine phosphatase gamma (PTPRG) is classified as a R5 of the receptor type (RPTPs) subfamily and is broadly expressed in various isoforms in different tissues. PTPRG is considered a tumor-suppressor gene (TSG) mapped on chromosome 3p14-21, a region frequently subject to loss of heterozygosity in various tumors. However, reported mechanisms of PTPRG downregulation include missense mutations, ncRNA gene regulation and epigenetic silencing by hypermethylation of CpG sites on promoter region causing loss of function of the gene product. Inactive forms or total loss of PTPRG protein have been described in sporadic and Lynch syndrome colorectal cancer, nasopharyngeal carcinoma, ovarian, breast, and lung cancers, gastric cancer or diseases affecting the hematopoietic compartment as Lymphoma and Leukemia. Noteworthy, in Central Nervous System (CNS) PTPRZ/PTPRG appears to be crucial in maintaining glioblastoma cell-related neuronal stemness, carving out a pathological functional role also in this tissue. In this review, we will summarize the current knowledge on the role of PTPRG in various human cancers.
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Affiliation(s)
- Christian Boni
- Department of Medicine, General Pathology Division, University of Verona, Verona, Italy
| | - Claudio Sorio
- Department of Medicine, General Pathology Division, University of Verona, Verona, Italy
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Boni C, Laudanna C, Sorio C. A Comprehensive Review of Receptor-Type Tyrosine-Protein Phosphatase Gamma (PTPRG) Role in Health and Non-Neoplastic Disease. Biomolecules 2022; 12:84. [PMID: 35053232 PMCID: PMC8773835 DOI: 10.3390/biom12010084] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 12/30/2021] [Accepted: 12/30/2021] [Indexed: 02/07/2023] Open
Abstract
Protein tyrosine phosphatase receptor gamma (PTPRG) is known to interact with and regulate several tyrosine kinases, exerting a tumor suppressor role in several type of cancers. Its wide expression in human tissues compared to the other component of group 5 of receptor phosphatases, PTPRZ expressed as a chondroitin sulfate proteoglycan in the central nervous system, has raised interest in its role as a possible regulatory switch of cell signaling processes. Indeed, a carbonic anhydrase-like domain (CAH) and a fibronectin type III domain are present in the N-terminal portion and were found to be associated with its role as [HCO3-] sensor in vascular and renal tissues and a possible interaction domain for cell adhesion, respectively. Studies on PTPRG ligands revealed the contactins family (CNTN) as possible interactors. Furthermore, the correlation of PTPRG phosphatase with inflammatory processes in different normal tissues, including cancer, and the increasing amount of its soluble form (sPTPRG) in plasma, suggest a possible role as inflammatory marker. PTPRG has important roles in human diseases; for example, neuropsychiatric and behavioral disorders and various types of cancer such as colon, ovary, lung, breast, central nervous system, and inflammatory disorders. In this review, we sum up our knowledge regarding the latest discoveries in order to appreciate PTPRG function in the various tissues and diseases, along with an interactome map of its relationship with a group of validated molecular interactors.
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Affiliation(s)
| | | | - Claudio Sorio
- Department of Medicine, General Pathology Division, University of Verona, 37134 Verona, Italy; (C.B.); (C.L.)
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Ion Channels, Transporters, and Sensors Interact with the Acidic Tumor Microenvironment to Modify Cancer Progression. Rev Physiol Biochem Pharmacol 2021; 182:39-84. [PMID: 34291319 DOI: 10.1007/112_2021_63] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Solid tumors, including breast carcinomas, are heterogeneous but typically characterized by elevated cellular turnover and metabolism, diffusion limitations based on the complex tumor architecture, and abnormal intra- and extracellular ion compositions particularly as regards acid-base equivalents. Carcinogenesis-related alterations in expression and function of ion channels and transporters, cellular energy levels, and organellar H+ sequestration further modify the acid-base composition within tumors and influence cancer cell functions, including cell proliferation, migration, and survival. Cancer cells defend their cytosolic pH and HCO3- concentrations better than normal cells when challenged with the marked deviations in extracellular H+, HCO3-, and lactate concentrations typical of the tumor microenvironment. Ionic gradients determine the driving forces for ion transporters and channels and influence the membrane potential. Cancer and stromal cells also sense abnormal ion concentrations via intra- and extracellular receptors that modify cancer progression and prognosis. With emphasis on breast cancer, the current review first addresses the altered ion composition and the changes in expression and functional activity of ion channels and transporters in solid cancer tissue. It then discusses how ion channels, transporters, and cellular sensors under influence of the acidic tumor microenvironment shape cancer development and progression and affect the potential of cancer therapies.
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