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Buyukavsar C, Sonmez M, Sagdic SK, Unal MH. Relationship between ganglion cell complex thickness and vision in age-related macular degeneration treated with aflibercept. Eur J Ophthalmol 2022:11206721221149065. [PMID: 36579800 DOI: 10.1177/11206721221149065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
PURPOSE This study aimed to analyze the correlation between ganglion cell complex thickness (GCCT) and vision compared with the choroidal thickness (CT) and central retinal thickness (CRT) in relation to the outcomes of intravitreal aflibercept treatment for choroidal neovascular membranes secondary to age-related macular degeneration (AMD). METHODS This was a prospective, observational study. Forty-three eyes of 38 patients with wet AMD received a monthly loading dose of 2 mg aflibercept by intravitreal injection (IVI) during the first 3 months and were then followed at regular monthly intervals for an average of 10 months by a pro re nata regimen. All patients were examined using spectral domain-optic coherence tomography (OCT) and enhanced depth imaging OCT. According to their response to IVI treatment in the third month, patients were divided into 2 groups, both functionally and anatomically. RESULTS Three-month GCCT and optic disc retinal nerve fiber layer thickness (ODRNFLT) had the most correlation with the 10-month vision (p = 0.002, p = 0.02, respectively). While baseline GCCT was most correlated with the functional response, baseline CRT was most correlated with the anatomical response (p = 0.01, p = 0.004, respectively). CONCLUSIONS The results suggest that a reduction in 3-month GCCT indicates a good long-term vision outcome, while a reduction in 3-month ODRNFLT shows a poor long-term vision outcome. The literature suggests that this study is the first to demonstrate that baseline GCCT is more strongly correlated with the functional response than it is with CT and CRT. Hence, GCCT has a prognostic value for vision impairment.
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Affiliation(s)
- Cihan Buyukavsar
- Department of Ophthalmology, Aksehir State Hospital; Aksehir, 42560, Konya, Turkey
| | - Murat Sonmez
- Department of Ophthalmology, 506079Sultan Abdulhamid Khan Training and Research Hospital; Uskudar, 34660, Istanbul, Turkey
| | - Sercan Koray Sagdic
- Department of Ophthalmology, 605511Kilis State Hospital; 79000, Kilis, Turkey
| | - Melih Hamdi Unal
- Department of Ophthalmology, 506079Sultan Abdulhamid Khan Training and Research Hospital; Uskudar, 34660, Istanbul, Turkey
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Masip E, Donat E, Polo Miquel B, Ribes-Koninckx C. Bone mineral density in spanish children at the diagnosis of inflammatory bowel disease. Arch Osteoporos 2021; 16:96. [PMID: 34145515 DOI: 10.1007/s11657-021-00945-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 04/28/2021] [Indexed: 02/03/2023]
Abstract
UNLABELLED The association between low bone mineral density (BMD) and inflammatory bowel disease (IBD) is already known. Our study, performed in Spanish pediatric IBD patients at diagnosis onset, shows that low BMD already existed at the beginning of the disease. Low weight and height are also associated with low BMD and have to be considered as risk factors. INTRODUCTION Inflammatory bowel disease (IBD) has been reported to be associated, even at disease onset, with low bone mass. The aim of this study was to know the bone mineral density (BMD) status in the IBD pediatric population of group of Spanish children, at the time of diagnosis. MATERIAL AND METHODS Retrospective review of patients' records from pediatric IBD patients diagnosed in our unit in the last 10 years. BMD was measured at the time of diagnosis and was expressed by Z-score. RESULTS Fifty-seven patients were included. Sixty-one percent were male and 47.4% had Crohn's disease (CD). Average age was 11.18 (SD 2.24) years old. Median BMD Z-score was - 0.30 (interquartile range: - 1.10 to + 0.10). Low BMD, defined as Z-score ≤ - 2SD, was present in 5% of patients, but there was no single patient with osteoporosis. There were no differences in BMD between Ulcerative Colitis (UC) and CD. Statistical differences appeared between healthy Spanish pediatric population and our IBD cohort, these having lower BMD for the same age and gender. A linear regression analysis showed a significant association between BMD Z-score and patient´s weight and height Z-score with a p values of 0.001 and 0.048, respectively. CONCLUSIONS Suboptimal bone density is present at diagnosis in Spanish pediatric patients with IBD. There is no difference in BMD between patients with CD and UC. Lower weight and height are associated with a lower BMD; thus these data at IBD diagnosis should be considered as a risk factor for bone disease in the pediatric population.
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Affiliation(s)
- Etna Masip
- Pediatric Gastroenterology and Hepatology Unit, University Hospital La Fe, Avda. Fernando Abril Martorell 106, 46026, Valencia, Spain.
| | - Ester Donat
- Pediatric Gastroenterology and Hepatology Unit, University Hospital La Fe, Avda. Fernando Abril Martorell 106, 46026, Valencia, Spain
| | - Begoña Polo Miquel
- Pediatric Gastroenterology and Hepatology Unit, University Hospital La Fe, Avda. Fernando Abril Martorell 106, 46026, Valencia, Spain
| | - Carmen Ribes-Koninckx
- Pediatric Gastroenterology and Hepatology Unit, University Hospital La Fe, Avda. Fernando Abril Martorell 106, 46026, Valencia, Spain
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3
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The structure and function of protein kinase C-related kinases (PRKs). Biochem Soc Trans 2021; 49:217-235. [PMID: 33522581 PMCID: PMC7925014 DOI: 10.1042/bst20200466] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 12/29/2020] [Accepted: 01/07/2021] [Indexed: 11/17/2022]
Abstract
The protein kinase C-related kinase (PRK) family of serine/threonine kinases, PRK1, PRK2 and PRK3, are effectors for the Rho family small G proteins. An array of studies have linked these kinases to multiple signalling pathways and physiological roles, but while PRK1 is relatively well-characterized, the entire PRK family remains understudied. Here, we provide a holistic overview of the structure and function of PRKs and describe the molecular events that govern activation and autoregulation of catalytic activity, including phosphorylation, protein interactions and lipid binding. We begin with a structural description of the regulatory and catalytic domains, which facilitates the understanding of their regulation in molecular detail. We then examine their diverse physiological roles in cytoskeletal reorganization, cell adhesion, chromatin remodelling, androgen receptor signalling, cell cycle regulation, the immune response, glucose metabolism and development, highlighting isoform redundancy but also isoform specificity. Finally, we consider the involvement of PRKs in pathologies, including cancer, heart disease and bacterial infections. The abundance of PRK-driven pathologies suggests that these enzymes will be good therapeutic targets and we briefly report some of the progress to date.
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Fearing BV, Speer JE, Jing L, Kalathil A, P. Kelly M, M. Buchowski J, P. Zebala L, Luhmann S, C. Gupta M, A. Setton L. Verteporfin treatment controls morphology, phenotype, and global gene expression for cells of the human nucleus pulposus. JOR Spine 2020; 3:e1111. [PMID: 33392449 PMCID: PMC7770208 DOI: 10.1002/jsp2.1111] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 06/24/2020] [Accepted: 07/02/2020] [Indexed: 12/15/2022] Open
Abstract
Cells of the nucleus pulposus (NP) are essential contributors to extracellular matrix synthesis and function of the intervertebral disc. With age and degeneration, the NP becomes stiffer and more dehydrated, which is associated with a loss of phenotype and biosynthetic function for its resident NP cells. Also, with aging, the NP cell undergoes substantial morphological changes from a rounded shape with pronounced vacuoles in the neonate and juvenile, to one that is more flattened and spread with a loss of vacuoles. Here, we make use of the clinically relevant pharmacological treatment verteporfin (VP), previously identified as a disruptor of yes-associated protein-TEA domain family member-binding domain (TEAD) signaling, to promote morphological changes in adult human NP cells in order to study variations in gene expression related to differences in cell shape. Treatment of adult, degenerative human NP cells with VP caused a shift in morphology from a spread, fibroblastic-like shape to a rounded, clustered morphology with decreased transcriptional activity of TEAD and serum-response factor. These changes were accompanied by an increased expression of vacuoles, NP-specific gene markers, and biosynthetic activity. The contemporaneous observation of VP-induced changes in cell shape and prominent, time-dependent changes within the transcriptome of NP cells occurred over all timepoints in culture. Enriched gene sets with the transition to VP-induced cell rounding suggest a major role for cell adhesion, cytoskeletal remodeling, vacuolar lumen, and MAPK activity in the NP phenotypic and functional response to changes in cell shape.
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Affiliation(s)
- Bailey V. Fearing
- Department of Biomedical EngineeringWashington University in St. LouisSt. LouisMissouriUSA
- Department of Orthopaedic SurgeryAtrium Health Musculoskeletal InstituteCharlotteNorth CarolinaUSA
| | - Julie E. Speer
- Department of Biomedical EngineeringWashington University in St. LouisSt. LouisMissouriUSA
| | - Liufang Jing
- Department of Biomedical EngineeringWashington University in St. LouisSt. LouisMissouriUSA
| | - Aravind Kalathil
- Department of Biomedical EngineeringWashington University in St. LouisSt. LouisMissouriUSA
| | - Michael P. Kelly
- Department of Orthopaedic SurgeryWashington University in St. LouisSt. LouisMissouriUSA
| | - Jacob M. Buchowski
- Department of Orthopaedic SurgeryWashington University in St. LouisSt. LouisMissouriUSA
| | - Lukas P. Zebala
- Department of Orthopaedic SurgeryWashington University in St. LouisSt. LouisMissouriUSA
| | - Scott Luhmann
- Department of Orthopaedic SurgeryWashington University in St. LouisSt. LouisMissouriUSA
| | - Munish C. Gupta
- Department of Orthopaedic SurgeryWashington University in St. LouisSt. LouisMissouriUSA
| | - Lori A. Setton
- Department of Biomedical EngineeringWashington University in St. LouisSt. LouisMissouriUSA
- Department of Orthopaedic SurgeryWashington University in St. LouisSt. LouisMissouriUSA
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Cyclin-dependent kinase 1-mediated phosphorylation of protein kinase N1 promotes anchorage-independent growth and migration. Cell Signal 2020; 69:109546. [PMID: 31981797 DOI: 10.1016/j.cellsig.2020.109546] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/17/2020] [Accepted: 01/21/2020] [Indexed: 12/30/2022]
Abstract
Protein kinase N1 (PKN1) is a member of the protein kinase C superfamily. Aberrations of PKN1 kinase activity are involved in several human pathological processes, including cancer. We found that PKN family proteins (PKN1/2/3) are phosphorylated in response to antitubulin drug-induced mitotic arrest. We identified cyclin-dependent kinase 1 (CDK1) as the corresponding kinase for PKN protein phosphorylation. CDK1 phosphorylates PKN1 at S533, S537, S562, and S916 in vitro and in cells during drug-induced mitotic arrest. Immunofluorescence staining further confirmed that PKN1 phosphorylation occurs during normal mitosis in a CDK1-dependent manner. Knockdown of PKN1 significantly inhibited anchorage-independent growth and migration without affecting proliferation in multiple cancer cell lines. We further showed that mitotic phosphorylation is essential for PKN1's oncogenic function, as the non-phosphorylatable mutant PKN1-4A failed to rescue anchorage-independent growth and migration in PKN1-knockdown cells. Thus, our findings reveal a novel regulatory mechanism for PKN1 in mitosis and its role in tumorigenesis.
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PKN1 kinase-negative knock-in mice develop splenomegaly and leukopenia at advanced age without obvious autoimmune-like phenotypes. Sci Rep 2019; 9:13977. [PMID: 31562379 PMCID: PMC6764976 DOI: 10.1038/s41598-019-50419-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 08/30/2019] [Indexed: 01/08/2023] Open
Abstract
Protein kinase N1 (PKN1) knockout (KO) mice spontaneously form germinal centers (GCs) and develop an autoimmune-like disease with age. Here, we investigated the function of PKN1 kinase activity in vivo using aged mice deficient in kinase activity resulting from the introduction of a point mutation (T778A) in the activation loop of the enzyme. PKN1[T778A] mice reached adulthood without external abnormalities; however, the average spleen size and weight of aged PKN1[T778A] mice increased significantly compared to aged wild type (WT) mice. Histologic examination and Southern blot analyses of spleens showed extramedullary hematopoiesis and/or lymphomagenesis in some cases, although without significantly different incidences between PKN1[T778A] and WT mice. Additionally, flow cytometry revealed increased numbers in B220+, CD3+, Gr1+ and CD193+ leukocytes in the spleen of aged PKN1[T778A] mice, whereas the number of lymphocytes, neutrophils, eosinophils, and monocytes was reduced in the peripheral blood, suggesting an advanced impairment of leukocyte trafficking with age. Moreover, aged PKN1[T778A] mice showed no obvious GC formation nor autoimmune-like phenotypes, such as glomerulonephritis or increased anti-dsDNA antibody titer, in peripheral blood. Our results showing phenotypic differences between aged Pkn1-KO and PKN1[T778A] mice may provide insight into the importance of PKN1-specific kinase-independent functions in vivo.
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Marrocco V, Bogomolovas J, Ehler E, Dos Remedios CG, Yu J, Gao C, Lange S. PKC and PKN in heart disease. J Mol Cell Cardiol 2019; 128:212-226. [PMID: 30742812 PMCID: PMC6408329 DOI: 10.1016/j.yjmcc.2019.01.029] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/30/2019] [Accepted: 01/31/2019] [Indexed: 12/22/2022]
Abstract
The protein kinase C (PKC) and closely related protein kinase N (PKN) families of serine/threonine protein kinases play crucial cellular roles. Both kinases belong to the AGC subfamily of protein kinases that also include the cAMP dependent protein kinase (PKA), protein kinase B (PKB/AKT), protein kinase G (PKG) and the ribosomal protein S6 kinase (S6K). Involvement of PKC family members in heart disease has been well documented over the years, as their activity and levels are mis-regulated in several pathological heart conditions, such as ischemia, diabetic cardiomyopathy, as well as hypertrophic or dilated cardiomyopathy. This review focuses on the regulation of PKCs and PKNs in different pathological heart conditions and on the influences that PKC/PKN activation has on several physiological processes. In addition, we discuss mechanisms by which PKCs and the closely related PKNs are activated and turned-off in hearts, how they regulate cardiac specific downstream targets and pathways, and how their inhibition by small molecules is explored as new therapeutic target to treat cardiomyopathies and heart failure.
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Affiliation(s)
- Valeria Marrocco
- Division of Cardiology, School of Medicine, University of California-San Diego, La Jolla, USA
| | - Julius Bogomolovas
- Division of Cardiology, School of Medicine, University of California-San Diego, La Jolla, USA; Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Elisabeth Ehler
- Randall Centre for Cell and Molecular Biophysics, School of Basic and Medical Biosciences, School of Cardiovascular Medicine and Sciences, British Heart Foundation Research Excellence Centre, King's College London, New Hunt's House, Guy's Campus, London SE1 1UL, UK
| | | | - Jiayu Yu
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chen Gao
- Division of Molecular Medicine, Department of Anesthesiology, David Geffen School of Medicine at UCLA, University of California-Los Angeles, Los Angeles, USA.
| | - Stephan Lange
- Division of Cardiology, School of Medicine, University of California-San Diego, La Jolla, USA; University of Gothenburg, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, Gothenburg, Sweden.
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8
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Venkadakrishnan VB, DePriest AD, Kumari S, Senapati D, Ben-Salem S, Su Y, Mudduluru G, Hu Q, Cortes E, Pop E, Mohler JL, Azabdaftari G, Attwood K, Shah RB, Jamieson C, Dehm SM, Magi-Galluzzi C, Klein E, Sharifi N, Liu S, Heemers HV. Protein Kinase N1 control of androgen-responsive serum response factor action provides rationale for novel prostate cancer treatment strategy. Oncogene 2019; 38:4496-4511. [PMID: 30742064 DOI: 10.1038/s41388-019-0732-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 01/11/2019] [Accepted: 01/23/2019] [Indexed: 12/15/2022]
Abstract
Sustained reliance on androgen receptor (AR) after failure of AR-targeting androgen deprivation therapy (ADT) prevents effective treatment of castration-recurrent (CR) prostate cancer (CaP). Interfering with the molecular machinery by which AR drives CaP progression may be an alternative therapeutic strategy but its feasibility remains to be tested. Here, we explore targeting the mechanism by which AR, via RhoA, conveys androgen-responsiveness to serum response factor (SRF), which controls aggressive CaP behavior and is maintained in CR-CaP. Following a siRNA screen and candidate gene approach, RNA-Seq studies confirmed that the RhoA effector Protein Kinase N1 (PKN1) transduces androgen-responsiveness to SRF. Androgen treatment induced SRF-PKN1 interaction, and PKN1 knockdown or overexpression severely impaired or stimulated, respectively, androgen regulation of SRF target genes. PKN1 overexpression occurred during clinical CR-CaP progression, and hastened CaP growth and shortened CR-CaP survival in orthotopic CaP xenografts. PKN1's effects on SRF relied on its kinase domain. The multikinase inhibitor lestaurtinib inhibited PKN1 action and preferentially affected androgen regulation of SRF over direct AR target genes. In a CR-CaP patient-derived xenograft, expression of SRF target genes was maintained while AR target gene expression declined and proliferative gene expression increased. PKN1 inhibition decreased viability of CaP cells before and after ADT. In patient-derived CaP explants, lestaurtinib increased AR target gene expression but did not significantly alter SRF target gene or proliferative gene expression. These results provide proof-of-principle for selective forms of ADT that preferentially target different fractions of AR's transcriptional output to inhibit CaP growth.
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Affiliation(s)
- Varadha Balaji Venkadakrishnan
- Department of Cancer Biology, Cleveland Clinic, Cleveland, OH, USA.,Department of Biological, Geological and Environmental Sciences, Cleveland State University, Cleveland, OH, USA
| | - Adam D DePriest
- Department of Cancer Genetics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Sangeeta Kumari
- Department of Cancer Biology, Cleveland Clinic, Cleveland, OH, USA
| | | | - Salma Ben-Salem
- Department of Cancer Biology, Cleveland Clinic, Cleveland, OH, USA
| | - Yixue Su
- Department of Cancer Biology, Cleveland Clinic, Cleveland, OH, USA
| | | | - Qiang Hu
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Eduardo Cortes
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Elena Pop
- Department of Urology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - James L Mohler
- Department of Urology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Gissou Azabdaftari
- Department of Urology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA.,Department of Pathology and Laboratory Medicine, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Kristopher Attwood
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Rajal B Shah
- Department of Anatomic Pathology, Cleveland Clinic, Cleveland, OH, USA
| | - Christina Jamieson
- Department of Urology, University of California, San Diego, LaJolla, CA, USA
| | - Scott M Dehm
- Masonic Cancer Center and Departments of Laboratory Medicine and Pathology and Urology, University of Minnesota, Minneapolis, MN, USA
| | | | - Eric Klein
- Department of Urology, Cleveland Clinic, Cleveland, OH, USA
| | - Nima Sharifi
- Department of Cancer Biology, Cleveland Clinic, Cleveland, OH, USA.,Department of Urology, Cleveland Clinic, Cleveland, OH, USA.,Department of Hematology/Medical Oncology, Cleveland Clinic, Cleveland, OH, USA
| | - Song Liu
- Department of Biostatistics and Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Hannelore V Heemers
- Department of Cancer Biology, Cleveland Clinic, Cleveland, OH, USA. .,Department of Urology, Cleveland Clinic, Cleveland, OH, USA. .,Department of Hematology/Medical Oncology, Cleveland Clinic, Cleveland, OH, USA.
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Francois AA, Obasanjo-Blackshire K, Clark JE, Boguslavskyi A, Holt MR, Parker PJ, Marber MS, Heads RJ. Loss of Protein Kinase Novel 1 (PKN1) is associated with mild systolic and diastolic contractile dysfunction, increased phospholamban Thr17 phosphorylation, and exacerbated ischaemia-reperfusion injury. Cardiovasc Res 2018; 114:138-157. [PMID: 29045568 PMCID: PMC5815577 DOI: 10.1093/cvr/cvx206] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 03/17/2017] [Accepted: 10/13/2017] [Indexed: 01/20/2023] Open
Abstract
Aims PKN1 is a stress-responsive protein kinase acting downstream of small GTP-binding proteins of the Rho/Rac family. The aim was to determine its role in endogenous cardioprotection. Methods and results Hearts from PKN1 knockout (KO) or wild type (WT) littermate control mice were perfused in Langendorff mode and subjected to global ischaemia and reperfusion (I/R). Myocardial infarct size was doubled in PKN1 KO hearts compared to WT hearts. PKN1 was basally phosphorylated on the activation loop Thr778 PDK1 target site which was unchanged during I/R. However, phosphorylation of p42/p44-MAPK was decreased in KO hearts at baseline and during I/R. In cultured neonatal rat ventricular cardiomyocytes (NRVM) and NRVM transduced with kinase dead (KD) PKN1 K644R mutant subjected to simulated ischaemia/reperfusion (sI/R), PhosTag® gel analysis showed net dephosphorylation of PKN1 during sI and early R despite Thr778 phosphorylation. siRNA knockdown of PKN1 in NRVM significantly decreased cell survival and increased cell injury by sI/R which was reversed by WT- or KD-PKN1 expression. Confocal immunofluorescence analysis of PKN1 in NRVM showed increased localization to the sarcoplasmic reticulum (SR) during sI. GC-MS/MS and immunoblot analysis of PKN1 immunoprecipitates following sI/R confirmed interaction with CamKIIδ. Co-translocation of PKN1 and CamKIIδ to the SR/membrane fraction during sI correlated with phospholamban (PLB) Thr17 phosphorylation. siRNA knockdown of PKN1 in NRVM resulted in increased basal CamKIIδ activation and increased PLB Thr17 phosphorylation only during sI. In vivo PLB Thr17 phosphorylation, Sarco-Endoplasmic Reticulum Ca2+ ATPase (SERCA2) expression and Junctophilin-2 (Jph2) expression were also basally increased in PKN1 KO hearts. Furthermore, in vivo P-V loop analysis of the beat-to-beat relationship between rate of LV pressure development or relaxation and end diastolic P (EDP) showed mild but significant systolic and diastolic dysfunction with preserved ejection fraction in PKN1 KO hearts. Conclusion Loss of PKN1 in vivo significantly reduces endogenous cardioprotection and increases myocardial infarct size following I/R injury. Cardioprotection by PKN1 is associated with reduced CamKIIδ-dependent PLB Thr17 phosphorylation at the SR and therefore may stabilize the coupling of SR Ca2+ handling and contractile function, independent of its kinase activity.
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Affiliation(s)
- Asvi A Francois
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Kofo Obasanjo-Blackshire
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - James E Clark
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Andrii Boguslavskyi
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Mark R Holt
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
- Randall Division of Cell and Molecular Biophysics, King’s College London, New Hunt’s House, Guy’s Hospital Campus, London, UK
| | - Peter J Parker
- Division of Cancer Studies, School of Cancer and Pharmaceutical Sciences, Faculty of Life Sciences and Medicine, King’s College London, New Hunt’s House, Guy’s Hospital Campus, London, UK
- Protein Phosphorylation Laboratory, Francis Crick Institute, Lincoln’s Inn Fields, London, UK
| | - Michael S Marber
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
| | - Richard J Heads
- Department of Cardiology, School of Cardiovascular Medicine and Sciences, British Heart Foundation Centre for Research Excellence, Faculty of Life Sciences and Medicine, The Rayne Institute, King’s College London, St Thomas’s Hospital, Lambeth Palace Road, London, UK
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10
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Yuan Q, Ren C, Xu W, Petri B, Zhang J, Zhang Y, Kubes P, Wu D, Tang W. PKN1 Directs Polarized RAB21 Vesicle Trafficking via RPH3A and Is Important for Neutrophil Adhesion and Ischemia-Reperfusion Injury. Cell Rep 2017; 19:2586-2597. [PMID: 28636945 PMCID: PMC5548392 DOI: 10.1016/j.celrep.2017.05.080] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/18/2017] [Accepted: 05/24/2017] [Indexed: 01/08/2023] Open
Abstract
Polarized vesicle transport plays an important role in cell polarization, but the mechanisms underlying this process and its role in innate immune responses are not well understood. Here, we describe a phosphorylation-regulated polarization mechanism that is important for neutrophil adhesion to endothelial cells during inflammatory responses. We show that the protein kinase PKN1 phosphorylates RPH3A, which enhances binding of RPH3A to guanosine triphosphate (GTP)-bound RAB21. These interactions are important for polarized localization of RAB21 and RPH3A in neutrophils, which leads to PIP5K1C90 polarization. Consistent with the roles of PIP5K1C90 polarization, the lack of PKN1 or RPH3A impairs neutrophil integrin activation, adhesion to endothelial cells, and infiltration in inflammatory models. Furthermore, myeloid-specific loss of PKN1 decreases tissue injury in a renal ischemia-reperfusion model. Thus, this study characterizes a mechanism for protein polarization in neutrophils and identifies a potential protein kinase target for therapeutic intervention in reperfusion-related tissue injury.
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Affiliation(s)
- Qianying Yuan
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale School of Medicine, New Haven, CT 06520, USA
| | - Chunguang Ren
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale School of Medicine, New Haven, CT 06520, USA
| | - Wenwen Xu
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale School of Medicine, New Haven, CT 06520, USA
| | - Björn Petri
- Snyder Institute for Chronic Diseases Mouse Phenomics Resource Laboratory, University of Calgary, Calgary, AB T2N 4N1, Canada; Department of Microbiology, Immunology and Infectious Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Jiasheng Zhang
- Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06520, USA
| | - Yong Zhang
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale School of Medicine, New Haven, CT 06520, USA
| | - Paul Kubes
- Snyder Institute for Chronic Diseases Mouse Phenomics Resource Laboratory, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Dianqing Wu
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale School of Medicine, New Haven, CT 06520, USA.
| | - Wenwen Tang
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale School of Medicine, New Haven, CT 06520, USA.
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Wang F, Zhan R, Chen L, Dai X, Wang W, Guo R, Li X, Li Z, Wang L, Huang S, Shen J, Li S, Cao C. RhoA promotes epidermal stem cell proliferation via PKN1-cyclin D1 signaling. PLoS One 2017; 12:e0172613. [PMID: 28222172 PMCID: PMC5319766 DOI: 10.1371/journal.pone.0172613] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 02/06/2017] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE Epidermal stem cells (ESCs) play a critical role in wound healing, but the mechanism underlying ESC proliferation is not well defined. Here, we explore the effects of RhoA on ESC proliferation and the possible underlying mechanism. METHODS Human ESCs were enriched by rapid adhesion to collagen IV. RhoA(+/+)(G14V), RhoA(-/-)(T19N) and pGFP control plasmids were transfected into human ESCs. The effect of RhoA on cell proliferation was detected by cell proliferation and DNA synthesis assays. Induction of PKN1 activity by RhoA was determined by immunoblot analysis, and the effects of PKN1 on RhoA in terms of inducing cell proliferation and cyclin D1 expression were detected using specific siRNA targeting PKN1. The effects of U-46619 (a RhoA agonist) and C3 transferase (a RhoA antagonist) on ESC proliferation were observed in vivo. RESULTS RhoA had a positive effect on ESC proliferation, and PKN1 activity was up-regulated by the active RhoA mutant (G14V) and suppressed by RhoA T19N. Moreover, the ability of RhoA to promote ESC proliferation and DNA synthesis was interrupted by PKN1 siRNA. Additionally, cyclin D1 protein and mRNA expression levels were up-regulated by RhoA G14V, and these effects were inhibited by siRNA-mediated knock-down of PKN1. RhoA also promoted ESC proliferation via PKN in vivo. CONCLUSION This study shows that the effect of RhoA on ESC proliferation is mediated by activation of the PKN1-cyclin D1 pathway in vitro, suggesting that RhoA may serve as a new therapeutic target for wound healing.
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Affiliation(s)
- Fan Wang
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Rixing Zhan
- School of Nursing, Third Military Medical University, Chongqing, China
| | - Liang Chen
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Xia Dai
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Wenping Wang
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Rui Guo
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Xiaoge Li
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Zhe Li
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Liang Wang
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Shupeng Huang
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Jie Shen
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
| | - Shirong Li
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
- * E-mail: (LS); (CC)
| | - Chuan Cao
- Department of Plastic and Reconstructive Surgery, Southwestern Hospital, Third Military Medical University, Chongqing, China
- * E-mail: (LS); (CC)
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12
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Hatakeyama R, Kono K, Yoshida S. Ypk1 and Ypk2 kinases maintain Rho1 at the plasma membrane by flippase-dependent lipid remodeling after membrane stresses. J Cell Sci 2017; 130:1169-1178. [PMID: 28167678 DOI: 10.1242/jcs.198382] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 02/01/2017] [Indexed: 01/15/2023] Open
Abstract
The plasma membrane (PM) is frequently challenged by mechanical stresses. In budding yeast, TORC2-Ypk1/Ypk2 kinase cascade plays a crucial role in PM stress responses by reorganizing the actin cytoskeleton via Rho1 GTPase. However, the molecular mechanism by which TORC2-Ypk1/Ypk2 regulates Rho1 is not well defined. Here, we found that Ypk1/Ypk2 maintain PM localization of Rho1 under PM stress via spatial reorganization of the lipids including phosphatidylserine. Genetic evidence suggests that this process is mediated by the Lem3-containing lipid flippase. We propose that lipid remodeling mediated by the TORC2-Ypk1/Ypk2-Lem3 axis is a backup mechanism for PM anchoring of Rho1 after PM stress-induced acute degradation of phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], which is responsible for Rho1 localization under normal conditions. Since all the signaling molecules studied here are conserved in higher eukaryotes, our findings might represent a general mechanism to cope with PM stress.
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Affiliation(s)
- Riko Hatakeyama
- Department of Biology and Rosenstiel Basic Biomedical Research Center, Brandeis University, 415 South Street, Waltham, MA 02454, USA .,Department of Biology, University of Fribourg, Chemin du Musée 10, Fribourg CH-1700, Switzerland
| | - Keiko Kono
- Department of Cell Biology, Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan
| | - Satoshi Yoshida
- Department of Biology and Rosenstiel Basic Biomedical Research Center, Brandeis University, 415 South Street, Waltham, MA 02454, USA .,Gunma Initiative for Advanced Research (GIAR), Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma 371-8512, Japan.,Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma 371-8512, Japan
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13
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Zhou X, Naguro I, Ichijo H, Watanabe K. Mitogen-activated protein kinases as key players in osmotic stress signaling. Biochim Biophys Acta Gen Subj 2016; 1860:2037-52. [PMID: 27261090 DOI: 10.1016/j.bbagen.2016.05.032] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 05/21/2016] [Indexed: 11/29/2022]
Abstract
BACKGROUND Osmotic stress arises from the difference between intracellular and extracellular osmolality. It induces cell swelling or shrinkage as a consequence of water influx or efflux, which threatens cellular activities. Mitogen-activated protein kinases (MAPKs) play central roles in signaling pathways in osmotic stress responses, including the regulation of intracellular levels of inorganic ions and organic osmolytes. SCOPE OF REVIEW The present review summarizes the cellular osmotic stress response and the function and regulation of the vertebrate MAPK signaling pathways involved. We also describe recent findings regarding apoptosis signal-regulating kinase 3 (ASK3), a MAP3K member, to demonstrate its regulatory effects on signaling molecules beyond MAPKs. MAJOR CONCLUSIONS MAPKs are rapidly activated by osmotic stress and have diverse roles, such as cell volume regulation, gene expression, and cell survival/death. There is significant cell type specificity in the function and regulation of MAPKs. Based on its activity change during osmotic stress and its regulation of the WNK1-SPAK/OSR1 pathway, ASK3 is expected to play important roles in osmosensing mechanisms and cellular functions related to osmoregulation. GENERAL SIGNIFICANCE MAPKs are essential for various cellular responses to osmotic stress; thus, the identification of the upstream regulators of MAPK pathways will provide valuable clues regarding the cellular osmosensing mechanism, which remains elusive in mammals. The elucidation of in vivo MAPK functions is also important because osmotic stress in physiological and pathophysiological conditions often results from changes in the intracellular osmolality. These studies potentially contribute to the establishment of therapeutic strategies against diseases that accompany osmotic perturbation.
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Affiliation(s)
- Xiangyu Zhou
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Isao Naguro
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Hidenori Ichijo
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kengo Watanabe
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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14
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Thauerer B, Zur Nedden S, Baier-Bitterlich G. Protein Kinase C-Related Kinase (PKN/PRK). Potential Key-Role for PKN1 in Protection of Hypoxic Neurons. Curr Neuropharmacol 2014; 12:213-8. [PMID: 24851086 PMCID: PMC4023452 DOI: 10.2174/1570159x11666131225000518] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 08/20/2013] [Accepted: 12/10/2013] [Indexed: 12/13/2022] Open
Abstract
Serine/threonine protein kinase C-related kinase (PKN/PRK) is a family of three isoenzymes (PKN1, PKN2,
PKN3), which are widely distributed in eukaryotic organisms and share the same overall domain structure. The Nterminal
region encompasses a conserved repeated domain, termed HR1a-c as well as a HR2/C2 domain. The
serine/threonine kinase domain is found in the C-terminal region of the protein and shows high sequence homology to
other members of the PKC superfamily.
In neurons, PKN1 is the most abundant isoform and has been implicated in a variety of functions including cytoskeletal
organization and neuronal differentiation and its deregulation may contribute to neuropathological processes such as
amyotrophic lateral sclerosis and Alzheimer’s disease. We have recently identified a candidate role of PKN1 in the
regulation of neuroprotective processes during hypoxic stress. Our key findings were that: 1) the activity of PKN1 was
significantly increased by hypoxia (1% O2) and neurotrophins (nerve growth factor and purine nucleosides); 2) Neuronal
cells, deficient of PKN1 showed a decrease of cell viability and neurite formation along with a disturbance of the F-actinassociated
cytoskeleton; 3) Purine nucleoside-mediated neuroprotection during hypoxia was severely hampered in PKN1
deficient neuronal cells, altogether suggesting a potentially critical role of PKN1 in neuroprotective processes.
This review gives an up-to-date overview of the PKN family with a special focus on the neuroprotective role of PKN1 in
hypoxia.
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Affiliation(s)
- Bettina Thauerer
- Medical University of Innsbruck, Biocenter/ Neurobiochemistry, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Stephanie Zur Nedden
- Medical University of Innsbruck, Biocenter/ Neurobiochemistry, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Gabriele Baier-Bitterlich
- Medical University of Innsbruck, Biocenter/ Neurobiochemistry, Innrain 80-82, A-6020 Innsbruck, Austria
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15
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Yan Y, Ding Y, Ming B, Du W, Kong X, Tian L, Zheng F, Fang M, Tan Z, Gong F. Increase in hypotonic stress-induced endocytic activity in macrophages via ClC-3. Mol Cells 2014; 37:418-25. [PMID: 24850147 PMCID: PMC4044314 DOI: 10.14348/molcells.2014.0031] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 04/01/2014] [Indexed: 12/26/2022] Open
Abstract
Extracellular hypotonic stress can affect cellular function. Whether and how hypotonicity affects immune cell function remains to be elucidated. Macrophages are immune cells that play key roles in adaptive and innate in immune reactions. The purpose of this study was to investigate the role and underlying mechanism of hypotonic stress in the function of bone marrow-derived macrophages (BMDMs). Hypotonic stress increased endocytic activity in BMDMs, but there was no significant change in the expression of CD80, CD86, and MHC class II molecules, nor in the secretion of TNF-α or IL-10 by BMDMs. Furthermore, the enhanced endocytic activity of BMDMs triggered by hypotonic stress was significantly inhibited by chloride channel-3 (ClC-3) siRNA. Our findings suggest that hypotonic stress can induce endocytosis in BMDMs and that ClC-3 plays a central role in the endocytic process.
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Affiliation(s)
- Yutao Yan
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
- Institute of Organ Transplantation, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
| | - Yu Ding
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
| | - Bingxia Ming
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
| | - Wenjiao Du
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
| | - Xiaoling Kong
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
| | - Li Tian
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
| | - Fang Zheng
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
| | - Min Fang
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
| | - Zheng Tan
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
| | - Feili Gong
- Department of Immunology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 4340030,
China
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16
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Marunaka Y. Characteristics and Pharmacological Regulation of Epithelial Na+ Channel (ENaC) and Epithelial Na+ Transport. J Pharmacol Sci 2014. [DOI: 10.1254/jphs.14r01sr] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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17
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Thumkeo D, Watanabe S, Narumiya S. Physiological roles of Rho and Rho effectors in mammals. Eur J Cell Biol 2013; 92:303-15. [PMID: 24183240 DOI: 10.1016/j.ejcb.2013.09.002] [Citation(s) in RCA: 170] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 09/25/2013] [Accepted: 09/25/2013] [Indexed: 02/06/2023] Open
Abstract
Rho GTPase is a master regulator controlling cytoskeleton in multiple contexts such as cell migration, adhesion and cytokinesis. Of several Rho GTPases in mammals, the best characterized is the Rho subfamily including ubiquitously expressed RhoA and its homologs RhoB and RhoC. Upon binding GTP, Rho exerts its functions through downstream Rho effectors, such as ROCK, mDia, Citron, PKN, Rhophilin and Rhotekin. Until recently, our knowledge about functions of Rho and Rho effectors came mostly from in vitro studies utilizing cultured cells, and their physiological roles in vivo were largely unknown. However, gene-targeting studies of Rho and its effectors have now unraveled their tissue- and cell-specific roles and provide deeper insight into the physiological function of Rho signaling in vivo. In this article, we briefly describe previous studies of the function of Rho and its effectors in vitro and then review and discuss recent studies on knockout mice of Rho and its effectors.
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Affiliation(s)
- Dean Thumkeo
- Department of Pharmacology, Kyoto University Faculty of Medicine, Sakyo-ku, Kyoto 606-8501, Japan; Innovation Center for Immunoregulation, Technologies and Drugs (AK Project), Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8501, Japan.
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18
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Loirand G, Sauzeau V, Pacaud P. Small G Proteins in the Cardiovascular System: Physiological and Pathological Aspects. Physiol Rev 2013; 93:1659-720. [DOI: 10.1152/physrev.00021.2012] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Small G proteins exist in eukaryotes from yeast to human and constitute the Ras superfamily comprising more than 100 members. This superfamily is structurally classified into five families: the Ras, Rho, Rab, Arf, and Ran families that control a wide variety of cell and biological functions through highly coordinated regulation processes. Increasing evidence has accumulated to identify small G proteins and their regulators as key players of the cardiovascular physiology that control a large panel of cardiac (heart rhythm, contraction, hypertrophy) and vascular functions (angiogenesis, vascular permeability, vasoconstriction). Indeed, basal Ras protein activity is required for homeostatic functions in physiological conditions, but sustained overactivation of Ras proteins or spatiotemporal dysregulation of Ras signaling pathways has pathological consequences in the cardiovascular system. The primary object of this review is to provide a comprehensive overview of the current progress in our understanding of the role of small G proteins and their regulators in cardiovascular physiology and pathologies.
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Affiliation(s)
- Gervaise Loirand
- INSERM, UMR S1087; University of Nantes; and CHU Nantes, l'Institut du Thorax, Nantes, France
| | - Vincent Sauzeau
- INSERM, UMR S1087; University of Nantes; and CHU Nantes, l'Institut du Thorax, Nantes, France
| | - Pierre Pacaud
- INSERM, UMR S1087; University of Nantes; and CHU Nantes, l'Institut du Thorax, Nantes, France
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19
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Regulation of epithelial sodium transport via epithelial Na+ channel. J Biomed Biotechnol 2011; 2011:978196. [PMID: 22028593 PMCID: PMC3196915 DOI: 10.1155/2011/978196] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2011] [Revised: 07/09/2011] [Accepted: 08/03/2011] [Indexed: 12/02/2022] Open
Abstract
Renal epithelial Na+ transport plays an important role in homeostasis of our body fluid content and blood pressure. Further, the Na+ transport in alveolar epithelial cells essentially controls the amount of alveolar fluid that should be kept at an appropriate level for normal gas exchange. The epithelial Na+ transport is generally mediated through two steps: (1) the entry step of Na+ via epithelial Na+ channel (ENaC) at the apical membrane and (2) the extrusion step of Na+ via the Na+, K+-ATPase at the basolateral membrane. In general, the Na+ entry via ENaC is the rate-limiting step. Therefore, the regulation of ENaC plays an essential role in control of blood pressure and normal gas exchange. In this paper, we discuss two major factors in ENaC regulation: (1) activity of individual ENaC and (2) number of ENaC located at the apical membrane.
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