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Bolanle IO, Palmer TM. O-GlcNAcylation and Phosphorylation Crosstalk in Vascular Smooth Muscle Cells: Cellular and Therapeutic Significance in Cardiac and Vascular Pathologies. Int J Mol Sci 2025; 26:3303. [PMID: 40244145 PMCID: PMC11989994 DOI: 10.3390/ijms26073303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2025] [Revised: 03/26/2025] [Accepted: 03/31/2025] [Indexed: 04/18/2025] Open
Abstract
More than 400 different types of post-translational modifications (PTMs), including O-GlcNAcylation and phosphorylation, combine to co-ordinate almost all aspects of protein function. Often, these PTMs overlap and the specific relationship between O-GlcNAcylation and phosphorylation has drawn much attention. In the last decade, the significance of this dynamic crosstalk has been linked to several chronic pathologies of cardiovascular origin. However, very little is known about the pathophysiological significance of this crosstalk for vascular smooth muscle cell dysfunction in cardiovascular disease. O-GlcNAcylation occurs on serine and threonine residues which are also targets for phosphorylation. A growing body of research has now emerged linking altered vascular integrity and homeostasis with highly regulated crosstalk between these PTMs. Additionally, a significant body of evidence indicates that O-GlcNAcylation is an important contributor to the pathogenesis of neointimal hyperplasia and vascular restenosis responsible for long-term vein graft failure. In this review, we evaluate the significance of this dynamic crosstalk and its role in cardiovascular pathologies, and the prospects of identifying possible targets for more effective therapeutic interventions.
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Affiliation(s)
| | - Timothy M. Palmer
- Biomedical Institute for Multimorbidity, Centre for Biomedicine, Hull York Medical School, University of Hull, Hull HU6 7RX, UK;
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2
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Tu W, Wang H, Zhang Y, Huang J, Diao Y, Zhou J, Tan Y, Li X. Investigation of the Molecular Mechanism of Asthma in Meishan Pigs Using Multi-Omics Analysis. Animals (Basel) 2025; 15:200. [PMID: 39858200 PMCID: PMC11759154 DOI: 10.3390/ani15020200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2024] [Revised: 01/07/2025] [Accepted: 01/09/2025] [Indexed: 01/27/2025] Open
Abstract
Asthma has been extensively studied in humans and animals, but the molecular mechanisms underlying asthma in Meishan pigs, a breed with distinct genetic and physiological characteristics, remain elusive. Understanding these mechanisms could provide insights into veterinary medicine and human asthma research. We investigated asthma pathogenesis in Meishan pigs through transcriptomic and metabolomic analyses of blood samples taken during autumn and winter. Asthma in Meishan pigs is related to inflammation, mitochondrial oxidative phosphorylation, and tricarboxylic acid (TCA) cycle disorders. Related genes include CXCL10, CCL8, CCL22, CCL21, OLR1, and ACKR1, while metabolites include succinic acid, riboflavin-5-phosphate, and fumaric acid. Transcriptomic sequencing was performed on panting and normal Meishan pigs, and differentially expressed genes underwent functional enrichment screening. Metabolomic analysis revealed differential metabolites and pathways between groups. Combined analyses indicated that lung inflammation is influenced by genetic, allergenic, and environmental factors disrupting oxidative phosphorylation in lung mitochondria, affecting the TCA cycle. Mitochondrial reactive oxygen species, glutathione S-transferases, arginase 1 and RORC in immune regulation, the Notch pathway, YPEL4 in cell proliferation, and MARCKS in airway mucus secretion play roles in asthma pathogenesis. This study highlights that many cytokines and signaling pathways contribute to asthma. Further studies are needed to elucidate their complex interactions.
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Affiliation(s)
- Weilong Tu
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (W.T.); (H.W.); (Y.Z.); (J.H.); (Y.D.); (J.Z.)
- Key Laboratory of Livestock and Poultry Resources (Pig) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Shanghai 201106, China
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, China
| | - Hongyang Wang
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (W.T.); (H.W.); (Y.Z.); (J.H.); (Y.D.); (J.Z.)
- Key Laboratory of Livestock and Poultry Resources (Pig) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Shanghai 201106, China
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, China
| | - Yingying Zhang
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (W.T.); (H.W.); (Y.Z.); (J.H.); (Y.D.); (J.Z.)
- Key Laboratory of Livestock and Poultry Resources (Pig) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Shanghai 201106, China
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, China
| | - Ji Huang
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (W.T.); (H.W.); (Y.Z.); (J.H.); (Y.D.); (J.Z.)
- Key Laboratory of Livestock and Poultry Resources (Pig) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Shanghai 201106, China
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, China
| | - Yuduan Diao
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (W.T.); (H.W.); (Y.Z.); (J.H.); (Y.D.); (J.Z.)
- Key Laboratory of Livestock and Poultry Resources (Pig) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Shanghai 201106, China
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, China
| | - Jieke Zhou
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (W.T.); (H.W.); (Y.Z.); (J.H.); (Y.D.); (J.Z.)
- Key Laboratory of Livestock and Poultry Resources (Pig) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Shanghai 201106, China
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, China
| | - Yongsong Tan
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (W.T.); (H.W.); (Y.Z.); (J.H.); (Y.D.); (J.Z.)
- Key Laboratory of Livestock and Poultry Resources (Pig) Evaluation and Utilization, Ministry of Agriculture and Rural Affairs, Shanghai 201106, China
- Shanghai Engineering Research Center of Breeding Pig, Shanghai 201106, China
| | - Xin Li
- Institute of Animal Husbandry and Veterinary Science, Shanghai Academy of Agricultural Sciences, Shanghai 201106, China; (W.T.); (H.W.); (Y.Z.); (J.H.); (Y.D.); (J.Z.)
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Albert AP, Jahan KS, Greenberg HZE, Shamsaldeen YA. Role for the PIP 2-binding protein myristoylated alanine-rich C-kinase substrate in vascular tissue: A novel therapeutic target for cardiovascular disease. J Cell Commun Signal 2024; 18:e12052. [PMID: 39691873 PMCID: PMC11647048 DOI: 10.1002/ccs3.12052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 09/05/2024] [Accepted: 09/23/2024] [Indexed: 12/19/2024] Open
Abstract
In vascular smooth muscle cells (VSMCs) and vascular endothelial cells (VECs), phosphatidylinositol 4,5-bisphosphate (PIP2) acts as a substrate for phospholipase C (PLC)- and phosphoinositol 3-kinase (PI3K)-mediated signaling pathways and an unmodified ligand at ion channels and other macromolecules, which are key processes in the regulation of cell physiological and pathological phenotypes. It is envisaged that these distinct roles of PIP2 are achieved by PIP2-binding proteins, which act as PIP2 buffers to produce discrete pools of PIP2 that permits targeted release within the cell. This review discusses evidence for the expression, cell distribution, and role of myristoylated alanine-rich C-kinase substrate (MARCKS), a PIP2-binding protein, in cellular signaling and function of VSMCs. The review indicates the possibilities for MARCKS as a therapeutic target for vascular disease involving dysfunctional cell proliferation and migration, endothelial barrier permeability, and vascular contractility such as atherosclerosis, systemic and pulmonary hypertension, and sepsis.
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Affiliation(s)
- Anthony P. Albert
- Vascular Biology SectionCardiovascular & Genomics Research InstituteCity St. George'sUniversity of LondonLondonUK
| | - Kazi S. Jahan
- Vascular Biology SectionCardiovascular & Genomics Research InstituteCity St. George'sUniversity of LondonLondonUK
| | - Harry Z. E. Greenberg
- Vascular Biology SectionCardiovascular & Genomics Research InstituteCity St. George'sUniversity of LondonLondonUK
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4
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Ma K, Yin K, Li J, Ma L, Zhou Q, Lu X, Li B, Li J, Wei G, Zhang G. The Hypothalamic Epigenetic Landscape in Dietary Obesity. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2306379. [PMID: 38115764 PMCID: PMC10916675 DOI: 10.1002/advs.202306379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/20/2023] [Indexed: 12/21/2023]
Abstract
The hypothalamus in the brain plays a pivotal role in controlling energy balance in vertebrates. Nutritional excess through high-fat diet (HFD) feeding can dysregulate hypothalamic signaling at multiple levels. Yet, it remains largely unknown in what magnitude HFD feeding may impact epigenetics in this brain region. Here, it is shown that HFD feeding can significantly alter hypothalamic epigenetic events, including posttranslational histone modifications, DNA methylation, and chromatin accessibility. The authors comprehensively analyze the chromatin immunoprecipitation-sequencing (ChIP-seq), methylated DNA immunoprecipitation-sequencing (MeDIP-seq), single nucleus assay for transposase-accessible chromatin using sequencing (snATAC-seq), and RNA-seq data of the hypothalamus of C57 BL/6 mice fed with a chow or HFD for 1 to 6 months. The chromatins are categorized into 6 states using the obtained ChIP-seq data for H3K4me3, H3K27ac, H3K9me3, H3K27me3, and H3K36me3. A 1-month HFD feeding dysregulates histone modifications and DNA methylation more pronouncedly than that of 3- or 6-month. Besides, HFD feeding differentially impacts chromatin accessibility in hypothalamic cells. Thus, the epigenetic landscape is dysregulated in the hypothalamus of dietary obesity mice.
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Affiliation(s)
- Kai Ma
- Department of Hepatobiliary and Pancreatic Surgery and Zhejiang Provincial Key Laboratory of Pancreatic DiseaseThe First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang310003China
| | - Kaili Yin
- Key Laboratory of Environmental HealthMinistry of EducationDepartment of ToxicologySchool of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei430030China
- Institute for Brain ResearchCollaborative Innovation Center for Brain ScienceHuazhong University of Science and TechnologyWuhanHubei430030China
| | - Jiong Li
- Key Laboratory of Environmental HealthMinistry of EducationDepartment of ToxicologySchool of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei430030China
- Institute for Brain ResearchCollaborative Innovation Center for Brain ScienceHuazhong University of Science and TechnologyWuhanHubei430030China
| | - Li Ma
- CAS Key Laboratory of Computational BiologyShanghai Institute of Nutrition and HealthShanghai Institutes for Biological SciencesUniversity of Chinese Academy of Sciences (CAS)CASShanghai200031China
| | - Qun Zhou
- Key Laboratory of Environmental HealthMinistry of EducationDepartment of ToxicologySchool of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei430030China
- Institute for Brain ResearchCollaborative Innovation Center for Brain ScienceHuazhong University of Science and TechnologyWuhanHubei430030China
| | - Xiyuan Lu
- State Key Laboratory of Reproductive MedicineNanjing Medical UniversityNanjingJiangsu211166China
| | - Bo Li
- Department of EndocrinologyXinhua HospitalShanghai Jiao Tong University School of MedicineShanghai200092China
| | - Juxue Li
- State Key Laboratory of Reproductive MedicineNanjing Medical UniversityNanjingJiangsu211166China
| | - Gang Wei
- CAS Key Laboratory of Computational BiologyShanghai Institute of Nutrition and HealthShanghai Institutes for Biological SciencesUniversity of Chinese Academy of Sciences (CAS)CASShanghai200031China
| | - Guo Zhang
- Key Laboratory of Environmental HealthMinistry of EducationDepartment of ToxicologySchool of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei430030China
- Institute for Brain ResearchCollaborative Innovation Center for Brain ScienceHuazhong University of Science and TechnologyWuhanHubei430030China
- Department of Pathophysiology, School of Basic Medical SciencesHenan UniversityKaifengHenan475004China
- Institute of Metabolism and HealthHenan UniversityKaifengHenanChina
- Zhongzhou LaboratoryZhengzhouHenan450046China
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5
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Sharma B, Koren DT, Ghosh S. Nitric oxide modulates NMDA receptor through a negative feedback mechanism and regulates the dynamical behavior of neuronal postsynaptic components. Biophys Chem 2023; 303:107114. [PMID: 37832215 DOI: 10.1016/j.bpc.2023.107114] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 09/22/2023] [Accepted: 09/24/2023] [Indexed: 10/15/2023]
Abstract
Nitric oxide (NO) is known to be an important regulator of neurological processes in the central nervous system which acts directly on the presynaptic neuron and enhances the release of neurotransmitters like glutamate into the synaptic cleft. Calcium influx activates a cascade of biochemical reactions to influence the production of nitric oxide in the postsynaptic neuron. This has been modeled in the present work as a system of ordinary differential equations, to explore the dynamics of the interacting components and predict the dynamical behavior of the postsynaptic neuron. It has been hypothesized that nitric oxide modulates the NMDA receptor via a feedback mechanism and regulates the dynamic behavior of postsynaptic components. Results obtained by numerical analyses indicate that the biochemical system is stimulus-dependent and shows oscillations of calcium and other components within a limited range of concentration. Some of the parameters such as stimulus strength, extracellular calcium concentration, and rate of nitric oxide feedback are crucial for the dynamics of the components in the postsynaptic neuron.
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Affiliation(s)
- Bhanu Sharma
- Department of Biophysics, University of Delhi South Campus, New Delhi 110021, India
| | | | - Subhendu Ghosh
- Department of Biophysics, University of Delhi South Campus, New Delhi 110021, India.
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6
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Ammendola R, Parisi M, Esposito G, Cattaneo F. Pro-Resolving FPR2 Agonists Regulate NADPH Oxidase-Dependent Phosphorylation of HSP27, OSR1, and MARCKS and Activation of the Respective Upstream Kinases. Antioxidants (Basel) 2021; 10:antiox10010134. [PMID: 33477989 PMCID: PMC7835750 DOI: 10.3390/antiox10010134] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/11/2021] [Accepted: 01/14/2021] [Indexed: 12/12/2022] Open
Abstract
Background: Formyl peptide receptor 2 (FPR2) is involved in the pathogenesis of chronic inflammatory diseases, being activated either by pro-resolving or proinflammatory ligands. FPR2-associated signal transduction pathways result in phosphorylation of several proteins and in NADPH oxidase activation. We, herein, investigated molecular mechanisms underlying phosphorylation of heat shock protein 27 (HSP27), oxidative stress responsive kinase 1 (OSR1), and myristolated alanine-rich C-kinase substrate (MARCKS) elicited by the pro-resolving FPR2 agonists WKYMVm and annexin A1 (ANXA1). Methods: CaLu-6 cells or p22phoxCrispr/Cas9 double nickase CaLu-6 cells were incubated for 5 min with WKYMVm or ANXA1, in the presence or absence of NADPH oxidase inhibitors. Phosphorylation at specific serine residues of HSP27, OSR1, and MARCKS, as well as the respective upstream kinases activated by FPR2 stimulation was analysed. Results: Blockade of NADPH oxidase functions prevents WKYMVm- and ANXA1-induced HSP-27(Ser82), OSR1(Ser339) and MARCKS(Ser170) phosphorylation. Moreover, NADPH oxidase inhibitors prevent WKYMVm- and ANXA1-dependent activation of p38MAPK, PI3K and PKCδ, the kinases upstream to HSP-27, OSR1 and MARCKS, respectively. The same results were obtained in p22phoxCrispr/Cas9 cells. Conclusions: FPR2 shows an immunomodulatory role by regulating proinflammatory and anti-inflammatory activities and NADPH oxidase is a key regulator of inflammatory pathways. The activation of NADPH oxidase-dependent pro-resolving downstream signals suggests that FPR2 signalling and NADPH oxidase could represent novel targets for inflammation therapeutic intervention.
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Affiliation(s)
| | | | | | - Fabio Cattaneo
- Correspondence: ; Tel.: +39-081-746-2036; Fax: +39-081-746-4359
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7
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Kimura A, Toyoda T, Iwasaki M, Hirama R, Osafune K. Combined Omics Approaches Reveal the Roles of Non-canonical WNT7B Signaling and YY1 in the Proliferation of Human Pancreatic Progenitor Cells. Cell Chem Biol 2020; 27:1561-1572.e7. [PMID: 33125912 DOI: 10.1016/j.chembiol.2020.08.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 08/18/2020] [Accepted: 08/27/2020] [Indexed: 02/07/2023]
Abstract
The proliferation of human pancreatic progenitor cells (PPCs) is critical for developing cell therapies for diabetes. Here, using transcriptome analysis combined with small interfering RNA (siRNA) screening, we revealed that WNT7B is a downstream growth factor of AT7867, a compound known to promote the proliferation of PPCs generated from human pluripotent stem cells. Feeder cell lines stably expressing mouse Wnt7a or Wnt7b, but not other Wnts, enhanced PPC proliferation in the absence of AT7867. Importantly, Wnt7a/b ligands did not activate the canonical Wnt pathway, and PPC proliferation depended on the non-canonical Wnt/PKC pathway. A comparison of the phosphoproteome in response to AT7867 or a newly synthesized AT7867 derivative uncovered the function of YY1 as a transcriptional regulator of WNT7B. Overall, our data highlight unknown roles of non-canonical WNT7B/PKC signaling and YY1 in human PPC proliferation and will contribute to the stable supply of a cell source for pancreatic disease modeling and therapeutic applications.
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Affiliation(s)
- Azuma Kimura
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto 606-8507, Japan
| | - Taro Toyoda
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto 606-8507, Japan
| | - Mio Iwasaki
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto 606-8507, Japan
| | - Ryusuke Hirama
- Research Institute for Bioscience Products and Fine Chemicals, Ajinomoto Co., Inc., Kawasaki, Kanagawa 210-8681, Japan
| | - Kenji Osafune
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto 606-8507, Japan.
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Kim DW, Washington PW, Wang ZQ, Lin SH, Sun C, Ismail BT, Wang H, Jiang L, Blackshaw S. The cellular and molecular landscape of hypothalamic patterning and differentiation from embryonic to late postnatal development. Nat Commun 2020; 11:4360. [PMID: 32868762 PMCID: PMC7459115 DOI: 10.1038/s41467-020-18231-z] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/12/2020] [Indexed: 12/22/2022] Open
Abstract
The hypothalamus is a central regulator of many innate behaviors essential for survival, but the molecular mechanisms controlling hypothalamic patterning and cell fate specification are poorly understood. To identify genes that control hypothalamic development, we have used single-cell RNA sequencing (scRNA-Seq) to profile mouse hypothalamic gene expression across 12 developmental time points between embryonic day 10 and postnatal day 45. This identified genes that delineated clear developmental trajectories for all major hypothalamic cell types, and readily distinguished major regional subdivisions of the developing hypothalamus. By using our developmental dataset, we were able to rapidly annotate previously unidentified clusters from existing scRNA-Seq datasets collected during development and to identify the developmental origins of major neuronal populations of the ventromedial hypothalamus. We further show that our approach can rapidly and comprehensively characterize mutants that have altered hypothalamic patterning, identifying Nkx2.1 as a negative regulator of prethalamic identity. These data serve as a resource for further studies of hypothalamic development, physiology, and dysfunction.
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Affiliation(s)
- Dong Won Kim
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Parris Whitney Washington
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Zoe Qianyi Wang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Sonia Hao Lin
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Changyu Sun
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Basma Taleb Ismail
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Hong Wang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Lizhi Jiang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Center for Human Systems Biology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
- Kavli Neuroscience Discovery Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
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9
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Jahan KS, Shi J, Greenberg HZE, Khavandi S, Baudel MMA, Barrese V, Greenwood IA, Albert AP. MARCKS mediates vascular contractility through regulating interactions between voltage-gated Ca 2+ channels and PIP 2. Vascul Pharmacol 2020; 132:106776. [PMID: 32707323 PMCID: PMC7549404 DOI: 10.1016/j.vph.2020.106776] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/16/2020] [Accepted: 07/17/2020] [Indexed: 12/25/2022]
Abstract
Phosphatidylinositol 4,5-bisphosphate (PIP2) acts as substrate and unmodified ligand for Gq-protein-coupled receptor signalling in vascular smooth muscle cells (VSMCs) that is central for initiating contractility. The present work investigated how PIP2 might perform these two potentially conflicting roles by studying the effect of myristoylated alanine-rich C kinase substrate (MARCKS), a PIP2-binding protein, on vascular contractility in rat and mouse mesenteric arteries. Using wire myography, MANS peptide (MANS), a MARCKS inhibitor, produced robust contractions with a pharmacological profile suggesting a predominantly role for L-type (CaV1.2) voltage-gated Ca2+ channels (VGCC). Knockdown of MARCKS using morpholino oligonucleotides reduced contractions induced by MANS and stimulation of α1-adrenoceptors and thromboxane receptors with methoxamine (MO) and U46619 respectively. Immunocytochemistry and proximity ligation assays demonstrated that MARCKS and CaV1.2 proteins co-localise at the plasma membrane in unstimulated tissue, and that MANS and MO reduced these interactions and induced translocation of MARCKS from the plasma membrane to the cytosol. Dot-blots revealed greater PIP2 binding to MARCKS than CaV1.2 in unstimulated tissue, with this binding profile reversed following stimulation by MANS and MO. MANS evoked an increase in peak amplitude and shifted the activation curve to more negative membrane potentials of whole-cell voltage-gated Ca2+ currents, which were prevented by depleting PIP2 levels with wortmannin. This present study indicates for the first time that MARCKS is important regulating vascular contractility and suggests that disinhibition of MARCKS by MANS or vasoconstrictors may induce contraction through releasing PIP2 into the local environment where it increases voltage-gated Ca2+ channel activity.
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Affiliation(s)
- Kazi S Jahan
- Vascular Biology Research Centre, Molecular and Clinical Research Institute, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Jian Shi
- Leeds Institute of Cardiovascular and Metabolic Medicine, Faculty of Medicine and Health, University of Leeds, Leeds LS2 9JT, UK
| | - Harry Z E Greenberg
- Vascular Biology Research Centre, Molecular and Clinical Research Institute, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Sam Khavandi
- Vascular Biology Research Centre, Molecular and Clinical Research Institute, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Miguel Martín-Aragón Baudel
- Department of Pharmacology, University of California, 451, Health Sciences Drive, Suite 3503, Davis, CA 95615, USA
| | - Vincenzo Barrese
- Department of Neurosciences, Reproductive Sciences and Dentistry, University of Naples Federico II, Corso Umberto I, 40, 80138 Napoli, NA, Italy
| | - Iain A Greenwood
- Vascular Biology Research Centre, Molecular and Clinical Research Institute, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Anthony P Albert
- Vascular Biology Research Centre, Molecular and Clinical Research Institute, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
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10
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Martín-Aragón Baudel MAS, Shi J, Large WA, Albert AP. Insights into Activation Mechanisms of Store-Operated TRPC1 Channels in Vascular Smooth Muscle. Cells 2020; 9:E179. [PMID: 31936855 PMCID: PMC7017204 DOI: 10.3390/cells9010179] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/03/2020] [Accepted: 01/05/2020] [Indexed: 01/10/2023] Open
Abstract
In vascular smooth muscle cells (VMSCs), the stimulation of store-operated channels (SOCs) mediate Ca2+ influx pathways which regulate important cellular functions including contraction, proliferation, migration, and growth that are associated with the development of vascular diseases. It is therefore important that we understand the biophysical, molecular composition, activation pathways, and physiological significance of SOCs in VSMCs as these maybe future therapeutic targets for conditions such as hypertension and atherosclerosis. Archetypal SOCs called calcium release-activated channels (CRACs) are composed of Orai1 proteins and are stimulated by the endo/sarcoplasmic reticulum Ca2+ sensor stromal interaction molecule 1 (STIM1) following store depletion. In contrast, this review focuses on proposals that canonical transient receptor potential (TRPC) channels composed of a heteromeric TRPC1/C5 molecular template, with TRPC1 conferring activation by store depletion, mediate SOCs in native contractile VSMCs. In particular, it summarizes our recent findings which describe a novel activation pathway of these TRPC1-based SOCs, in which protein kinase C (PKC)-dependent TRPC1 phosphorylation and phosphatidylinositol 4,5-bisphosphate (PIP2) are obligatory for channel opening. This PKC- and PIP2-mediated gating mechanism is regulated by the PIP2-binding protein myristoylated alanine-rich C kinase (MARCKS) and is coupled to store depletion by TRPC1-STIM1 interactions which induce Gq/PLCβ1 activity. Interestingly, the biophysical properties and activation mechanisms of TRPC1-based SOCs in native contractile VSMCs are unlikely to involve Orai1.
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Affiliation(s)
| | - Jian Shi
- LIGHT Laboratories, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds LS2 9JT, UK;
| | - William A. Large
- Vascular Biology Research Centre, Molecular and Clinical Research Institute, St. George’s, University of London, London SW17 0RE, UK;
| | - Anthony P. Albert
- Vascular Biology Research Centre, Molecular and Clinical Research Institute, St. George’s, University of London, London SW17 0RE, UK;
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11
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Phosphoproteomic analysis sheds light on intracellular signaling cascades triggered by Formyl-Peptide Receptor 2. Sci Rep 2019; 9:17894. [PMID: 31784636 PMCID: PMC6884478 DOI: 10.1038/s41598-019-54502-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 11/14/2019] [Indexed: 12/12/2022] Open
Abstract
Formyl peptide receptors (FPRs) belong to the family of seven transmembrane Gi-protein coupled receptors (GPCR). FPR2 is considered the most promiscuous member of this family since it recognizes a wide variety of ligands. It plays a crucial role in several physio-pathological processes and different studies highlighted the correlation between its expression and the higher propensity to invasion and metastasis of some cancers. FPR2 stimulation by its synthetic agonist WKYMVm triggers multiple phosphorylations of intracellular signaling molecules, such as ERKs, PKC, PKB, p38MAPK, PI3K, PLC, and of non-signaling proteins, such as p47phox and p67phox which are involved in NADPH oxidase-dependent ROS generation. Biological effects of FPR2 stimulation include intracellular Ca2+ mobilization, cellular proliferation and migration, and wound healing. A systematic analysis of the phosphoproteome in FPR2-stimulated cells has not been yet reported. Herein, we describe a large-scale phosphoproteomic study in WKYMVm-stimulated CaLu-6 cells. By using high resolution MS/MS we identified 290 differentially phosphorylated proteins and 53 unique phosphopeptides mapping on 40 proteins. Phosphorylations on five selected phospho-proteins were further validated by western blotting, confirming their dependence on FPR2 stimulation. Interconnection between some of the signalling readout identified was also evaluated. Furthermore, we show that FPR2 stimulation with two anti-inflammatory agonists induces the phosphorylation of selected differentially phosphorylated proteins, suggesting their role in the resolution of inflammation. These data provide a promising resource for further studies on new signaling networks triggered by FPR2 and on novel molecular drug targets for human diseases.
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Liu Z, Khalil RA. Evolving mechanisms of vascular smooth muscle contraction highlight key targets in vascular disease. Biochem Pharmacol 2018; 153:91-122. [PMID: 29452094 PMCID: PMC5959760 DOI: 10.1016/j.bcp.2018.02.012] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 02/12/2018] [Indexed: 12/11/2022]
Abstract
Vascular smooth muscle (VSM) plays an important role in the regulation of vascular function. Identifying the mechanisms of VSM contraction has been a major research goal in order to determine the causes of vascular dysfunction and exaggerated vasoconstriction in vascular disease. Major discoveries over several decades have helped to better understand the mechanisms of VSM contraction. Ca2+ has been established as a major regulator of VSM contraction, and its sources, cytosolic levels, homeostatic mechanisms and subcellular distribution have been defined. Biochemical studies have also suggested that stimulation of Gq protein-coupled membrane receptors activates phospholipase C and promotes the hydrolysis of membrane phospholipids into inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). IP3 stimulates initial Ca2+ release from the sarcoplasmic reticulum, and is buttressed by Ca2+ influx through voltage-dependent, receptor-operated, transient receptor potential and store-operated channels. In order to prevent large increases in cytosolic Ca2+ concentration ([Ca2+]c), Ca2+ removal mechanisms promote Ca2+ extrusion via the plasmalemmal Ca2+ pump and Na+/Ca2+ exchanger, and Ca2+ uptake by the sarcoplasmic reticulum and mitochondria, and the coordinated activities of these Ca2+ handling mechanisms help to create subplasmalemmal Ca2+ domains. Threshold increases in [Ca2+]c form a Ca2+-calmodulin complex, which activates myosin light chain (MLC) kinase, and causes MLC phosphorylation, actin-myosin interaction, and VSM contraction. Dissociations in the relationships between [Ca2+]c, MLC phosphorylation, and force have suggested additional Ca2+ sensitization mechanisms. DAG activates protein kinase C (PKC) isoforms, which directly or indirectly via mitogen-activated protein kinase phosphorylate the actin-binding proteins calponin and caldesmon and thereby enhance the myofilaments force sensitivity to Ca2+. PKC-mediated phosphorylation of PKC-potentiated phosphatase inhibitor protein-17 (CPI-17), and RhoA-mediated activation of Rho-kinase (ROCK) inhibit MLC phosphatase and in turn increase MLC phosphorylation and VSM contraction. Abnormalities in the Ca2+ handling mechanisms and PKC and ROCK activity have been associated with vascular dysfunction in multiple vascular disorders. Modulators of [Ca2+]c, PKC and ROCK activity could be useful in mitigating the increased vasoconstriction associated with vascular disease.
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Affiliation(s)
- Zhongwei Liu
- Vascular Surgery Research Laboratories, Division of Vascular and Endovascular Surgery, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA 02115, USA
| | - Raouf A Khalil
- Vascular Surgery Research Laboratories, Division of Vascular and Endovascular Surgery, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA 02115, USA.
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Westphal N, Loers G, Lutz D, Theis T, Kleene R, Schachner M. Generation and intracellular trafficking of a polysialic acid-carrying fragment of the neural cell adhesion molecule NCAM to the cell nucleus. Sci Rep 2017; 7:8622. [PMID: 28819302 PMCID: PMC5561184 DOI: 10.1038/s41598-017-09468-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 07/25/2017] [Indexed: 02/05/2023] Open
Abstract
Polysialic acid (PSA) and its major protein carrier, the neural cell adhesion molecule NCAM, play important roles in many nervous system functions during development and in adulthood. Here, we show that a PSA-carrying NCAM fragment is generated at the plasma membrane by matrix metalloproteases and transferred to the cell nucleus via endosomes and the cytoplasm. Generation and nuclear import of this fragment in cultured cerebellar neurons is induced by a function-triggering NCAM antibody and a peptide comprising the effector domain (ED) of myristoylated alanine-rich C kinase substrate (MARCKS) which interacts with PSA within the plane of the plasma membrane. These treatments lead to activation of the fibroblast growth factor (FGF) receptor, phospholipase C (PLC), protein kinase C (PKC) and phosphoinositide-3-kinase (PI3K), and subsequently to phosphorylation of MARCKS. Moreover, the NCAM antibody triggers calmodulin-dependent activation of nitric oxide synthase, nitric oxide (NO) production, NO-dependent S-nitrosylation of matrix metalloprotease 9 (MMP9) as well as activation of matrix metalloprotease 2 (MMP2) and MMP9, whereas the ED peptide activates phospholipase D (PLD) and MMP2, but not MMP9. These results indicate that the nuclear PSA-carrying NCAM fragment is generated by distinct and functionally defined signal transducing mechanisms.
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Affiliation(s)
- Nina Westphal
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, 20251, Hamburg, Germany
| | - Gabriele Loers
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, 20251, Hamburg, Germany
| | - David Lutz
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, 20251, Hamburg, Germany
- Institut für Strukturelle Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, 20251, Hamburg, Germany
| | - Thomas Theis
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, 20251, Hamburg, Germany
| | - Ralf Kleene
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, 20251, Hamburg, Germany
| | - Melitta Schachner
- Center for Neuroscience, Shantou University Medical College, 22 Xin Ling Road, Shantou, Guangdong, 515041, China.
- Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, 604 Allison Road, Piscataway, NJ, 08854, USA.
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Qvit N, Kornfeld OS, Mochly-Rosen D. Engineered Substrate-Specific Delta PKC Antagonists to Enhance Cardiac Therapeutics. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Nir Qvit
- Department of Chemical and Systems Biology, School of Medicine Stanford; Stanford University; CA 94305-5174 USA
| | - Opher S. Kornfeld
- Department of Chemical and Systems Biology, School of Medicine Stanford; Stanford University; CA 94305-5174 USA
| | - Daria Mochly-Rosen
- Department of Chemical and Systems Biology, School of Medicine Stanford; Stanford University; CA 94305-5174 USA
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Qvit N, Kornfeld OS, Mochly-Rosen D. Engineered Substrate-Specific Delta PKC Antagonists to Enhance Cardiac Therapeutics. Angew Chem Int Ed Engl 2016; 55:15672-15679. [PMID: 27860071 PMCID: PMC5308906 DOI: 10.1002/anie.201605429] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 09/30/2016] [Indexed: 01/27/2023]
Abstract
Most protein kinases phosphorylate multiple substrates, each of which induces different and sometimes opposing functions. Determining the role of phosphorylation of each substrate following a specific stimulus is challenging but is essential to elucidate the role of that substrate in the signaling event. Here we describe a rational approach to identify inhibitors of delta protein kinase C (δPKC), each inhibiting the phosphorylation of only one of δPKC's substrates. δPKC regulates many signaling events and we hypothesized that a docking inhibitor of a given substrate to δPKC should selectively abrogate the phosphorylation of only that substrate, without affecting the phosphorylation of the other δPKC substrates. Here we report the development of selective inhibitors of three δPKC substrates (in vitro Kd ≈3 nm); two greatly reduced ischemia-induced cardiac injury with an IC50 of ≈200 nm and the third had no effect, indicating that its respective substrate phosphorylation by δPKC has no role in the response to cardiac ischemia and reperfusion. The three inhibitors are highly specific; even at 1 μm, the phosphorylation of other δPKC protein substrates was unaffected. The rationale we describe is likely applicable for the development of other substrate-specific inhibitors as well.
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Affiliation(s)
- Nir Qvit
- Department of Chemical and Systems Biology, School of Medicine Stanford, Stanford University, CA, 94305-5174, USA
| | - Opher S Kornfeld
- Department of Chemical and Systems Biology, School of Medicine Stanford, Stanford University, CA, 94305-5174, USA
| | - Daria Mochly-Rosen
- Department of Chemical and Systems Biology, School of Medicine Stanford, Stanford University, CA, 94305-5174, USA
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Kültz D, Li J, Zhang X, Villarreal F, Pham T, Paguio D. Population-specific plasma proteomes of marine and freshwater three-spined sticklebacks (Gasterosteus aculeatus
). Proteomics 2015. [DOI: 10.1002/pmic.201500132] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dietmar Kültz
- Department of Animal Science; University of California; Davis CA USA
| | - Johnathon Li
- Department of Animal Science; University of California; Davis CA USA
| | - Xuezhen Zhang
- Department of Animal Science; University of California; Davis CA USA
- College of Fisheries; Huazhong Agricultural University; Wuhan P. R. China
| | | | - Tuan Pham
- Department of Animal Science; University of California; Davis CA USA
| | - Darlene Paguio
- Department of Animal Science; University of California; Davis CA USA
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Lippoldt J, Händel C, Dietrich U, Käs J. Dynamic membrane structure induces temporal pattern formation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:2380-90. [DOI: 10.1016/j.bbamem.2014.05.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 05/05/2014] [Accepted: 05/16/2014] [Indexed: 10/25/2022]
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18
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Two domains of the smoothelin-like 1 protein bind apo- and calcium–calmodulin independently. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:1580-90. [DOI: 10.1016/j.bbapap.2014.05.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 05/14/2014] [Accepted: 05/24/2014] [Indexed: 12/24/2022]
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19
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Alonso S, Bär M. Modeling domain formation of MARCKS and protein kinase C at cellular membranes. ACTA ACUST UNITED AC 2014. [DOI: 10.1140/epjnbp14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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20
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Shi J, Birnbaumer L, Large WA, Albert AP. Myristoylated alanine-rich C kinase substrate coordinates native TRPC1 channel activation by phosphatidylinositol 4,5-bisphosphate and protein kinase C in vascular smooth muscle. FASEB J 2013; 28:244-55. [PMID: 24022404 DOI: 10.1096/fj.13-238022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Canonical transient receptor potential 1 (TRPC1) Ca(2+)-permeable cation channels contribute to vascular tone and blood vessel remodeling and represent potential therapeutic targets for cardiovascular disease. Protein kinase C (PKC) and phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] are obligatory for native TRPC1 channel activation in vascular smooth muscle cells (VSMCs) but how PKC and PI(4,5)P2 act together to induce channel gating remains unresolved. The present study reveals that myristoylated alanine-rich C kinase substrate (MARCKS) protein coordinates activation of TRPC1 channels by PKC and PI(4,5)P2. TRPC1 channels and MARCKS form signaling complexes with PI(4,5)P2 bound to MARCKS; in this configuration TRPC1 channels are closed. Activators of TRPC1 channels induce PKC phosphorylation of TRPC1 proteins, which causes dissociation of TRPC1 subunits from MARCKS and release of PI(4,5)P2 from MARCKS; PI(4,5)P2 subsequently binds to TRPC1 subunits to induce channel opening. Calmodulin acting at, or upstream of, MARCKS is also required for TRPC1 channel opening through a similar gating mechanism involving PKC and PI(4,5)P2. These novel findings show that MARCKS coordinates native TRPC1 channel activation in VSMCs by acting as a reversible PI(4,5)P2 buffer, which is regulated by PKC-mediated TRPC1 phosphorylation. Moreover, our data provide evidence that PI(4,5)P2 is a gating ligand of TRPC1 channels.
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Affiliation(s)
- Jian Shi
- 1Pharmacology and Cell Physiology, Division of Biomedical Sciences, St. George's, University of London, Cranmer Terrace, London SW17 0RE, UK.
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Abstract
Primary B-cell disorders comprise a heterogeneous group of inherited immunodeficiencies, often associated with autoimmunity causing significant morbidity. The underlying genetic etiology remains elusive in the majority of patients. In this study, we investigated a patient from a consanguineous family suffering from recurrent infections and severe lupuslike autoimmunity. Immunophenotyping revealed progressive decrease of CD19(+) B cells, a defective class switch indicated by low numbers of IgM- and IgG-memory B cells, as well as increased numbers of CD21(low) B cells. Combined homozygosity mapping and exome sequencing identified a biallelic splice-site mutation in protein C kinase δ (PRKCD), causing the absence of the corresponding protein product. Consequently, phosphorylation of myristoylated alanine-rich C kinase substrate was decreased, and mRNA levels of nuclear factor interleukin (IL)-6 and IL-6 were increased. Our study uncovers human PRKCD deficiency as a novel cause of common variable immunodeficiency-like B-cell deficiency with severe autoimmunity.
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22
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Yang HQ, Li X, Yang WM, Feng SM, Ma JJ. Neuroprotective effects of new protein kinase C activator TPPB against Aβ₂₅₋₃₅ induced neurotoxicity in PC12 cells. Neurochem Res 2012; 37:2213-2221. [PMID: 22832950 DOI: 10.1007/s11064-012-0846-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 06/09/2012] [Accepted: 07/13/2012] [Indexed: 11/24/2022]
Abstract
Alzheimer's disease (AD) is pathologically characterized by presence of senile plaques in the hippocampus, which are composed mainly of extracellular deposition of a polypeptide known as the beta amyloid, the Aβ. It has been demonstrated on numerous occasions that it was the deposition and aggregation of this Aβ peptide that cause neuronal dysfunction and even finally, the dementia. Lowering the deposition of Aβ or decreasing its neurotoxicity has long been one of the purposes of AD therapy. In previous study, we reported that protein kinase C (PKC) activator TPPB could regulate APP processing by increasing α-secretase activity. In this study we further investigated the potential neuroprotective effect of TPPB against Aβ(25-35)-induced neurotoxicity in PC12 cells. The results indicated that TPPB at concentration of 1 μM could antagonize Aβ(25-35) induced cell damage as evidenced by MTT assays, LDH release and by morphological changes. Furthermore, the neuroprotection in cell viability can be blocked by inhibitors of PKC, Akt and MAPK. The experiment also indicated that TPPB could increase the phosphorylation of Akt, PKC, MARCKS and MAPK, which were inhibited by Aβ(25-35) treatment. Finally, TPPB inhibited the activation of caspase-3 induced by Aβ(25-35). Taken together, the experiment here implies that TPPB has a role against Aβ(25-35)-induced neurotoxicity in PC12 cells and may suggest its therapeutic potential in AD.
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Affiliation(s)
- Hong-Qi Yang
- Department of Neurology, Henan Provincial People's Hospital, Zhengzhou 450003, Henan Province, People's Republic of China.
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Lima VV, Giachini FR, Hardy DM, Webb RC, Tostes RC. O-GlcNAcylation: a novel pathway contributing to the effects of endothelin in the vasculature. Am J Physiol Regul Integr Comp Physiol 2010; 300:R236-50. [PMID: 21068200 DOI: 10.1152/ajpregu.00230.2010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Glycosylation with O-linked β-N-acetylglucosamine (O-GlcNAc) or O-GlcNAcylation on serine and threonine residues of nuclear and cytoplasmic proteins is a posttranslational modification that alters the function of numerous proteins important in vascular function, including kinases, phosphatases, transcription factors, and cytoskeletal proteins. O-GlcNAcylation is an innovative way to think about vascular signaling events both in physiological conditions and in disease states. This posttranslational modification interferes with vascular processes, mainly vascular reactivity, in conditions where endothelin-1 (ET-1) levels are augmented (e.g. salt-sensitive hypertension, ischemia/reperfusion, and stroke). ET-1 plays a crucial role in the vascular function of most organ systems, both in physiological and pathophysiological conditions. Recognition of ET-1 by the ET(A) and ET(B) receptors activates intracellular signaling pathways and cascades that result in rapid and long-term alterations in vascular activity and function. Components of these ET-1-activated signaling pathways (e.g., mitogen-activated protein kinases, protein kinase C, RhoA/Rho kinase) are also targets for O-GlcNAcylation. Recent experimental evidence suggests that ET-1 directly activates O-GlcNAcylation, and this posttranslational modification mediates important vascular effects of the peptide. This review focuses on ET-1-activated signaling pathways that can be modified by O-GlcNAcylation. A brief description of the O-GlcNAcylation biology is presented, and its role on vascular function is addressed. ET-1-induced O-GlcNAcylation and its implications for vascular function are then discussed. Finally, the interplay between O-GlcNAcylation and O-phosphorylation is addressed.
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Affiliation(s)
- Victor V Lima
- Department of Physiology, Medical College of Georgia, Augusta, Georgia, USA
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24
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Echave P, Machado-da-Silva G, Arkell RS, Duchen MR, Jacobson J, Mitter R, Lloyd AC. Extracellular growth factors and mitogens cooperate to drive mitochondrial biogenesis. J Cell Sci 2009; 122:4516-25. [PMID: 19920079 DOI: 10.1242/jcs.049734] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cells generate new organelles when stimulated by extracellular factors to grow and divide; however, little is known about how growth and mitogenic signalling pathways regulate organelle biogenesis. Using mitochondria as a model organelle, we have investigated this problem in primary Schwann cells, for which distinct factors act solely as mitogens (neuregulin) or as promoters of cell growth (insulin-like growth factor 1; IGF1). We find that neuregulin and IGF1 act synergistically to increase mitochondrial biogenesis and mitochondrial DNA replication, resulting in increased mitochondrial density in these cells. Moreover, constitutive oncogenic Ras signalling results in a further increase in mitochondrial density. This synergistic effect is seen at the global transcriptional level, requires both the ERK and phosphoinositide 3-kinase (PI3K) signalling pathways and is mediated by the transcription factor ERRalpha. Interestingly, the effect is independent of Akt-TOR signalling, a major regulator of cell growth in these cells. This separation of the pathways that drive mitochondrial biogenesis and cell growth provides a mechanism for the modulation of mitochondrial density according to the metabolic requirements of the cell.
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Affiliation(s)
- Pedro Echave
- MRC Laboratory for Molecular Cell Biology, The Cancer Institute, University College London, London, UK
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Monahan TS, Andersen ND, Martin MC, Malek JY, Shrikhande GV, Pradhan L, Ferran C, LoGerfo FW. MARCKS silencing differentially affects human vascular smooth muscle and endothelial cell phenotypes to inhibit neointimal hyperplasia in saphenous vein. FASEB J 2008; 23:557-64. [PMID: 18940893 DOI: 10.1096/fj.08-114173] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Intimal hyperplasia (IH) limits the patency of all cardiovascular vein bypass grafts. We previously found the myristoylated alanine-rich C kinase substrate (MARCKS), a key protein kinase C (PKC) substrate, to be up-regulated in canine models of IH. Here, we further characterize the role of MARCKS in IH and examine the phenotypic consequences of MARCKS silencing by small interfering RNA (siRNA) transfection in human vascular smooth muscle cells (VSMCs) and endothelial cells (ECs) in vitro and use a rapid 10-min nonviral siRNA transfection technique to determine the effects of MARCKS silencing in human saphenous vein cultured ex vivo. We demonstrate MARCKS silencing attenuates VSMC migration and arrests VSMC proliferation in part through the up-regulation of the cyclin-dependent kinase inhibitor p27(kip1). Conversely, MARCKS silencing had little or no effect on EC migration or proliferation. These phenotypic changes culminated in reduced neointimal formation in cultured human saphenous vein. These data identify MARCKS as a pathogenic contributor to IH and indicate therapeutic MARCKS silencing could selectively suppress the "atherogenic," proliferative phenotype of VSMCs without collateral harm to the endothelium. This approach could be readily translated to the clinic to silence MARCKS in vein bypass grafts prior to implantation.
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Affiliation(s)
- Thomas S Monahan
- Department of Surgery, Division of Vascular Surgery, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA
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Kim HR, Gallant C, Leavis PC, Gunst SJ, Morgan KG. Cytoskeletal remodeling in differentiated vascular smooth muscle is actin isoform dependent and stimulus dependent. Am J Physiol Cell Physiol 2008; 295:C768-78. [PMID: 18596213 DOI: 10.1152/ajpcell.00174.2008] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dynamic remodeling of the actin cytoskeleton plays an essential role in the migration and proliferation of vascular smooth muscle cells. It has been suggested that actin remodeling may also play an important functional role in nonmigrating, nonproliferating differentiated vascular smooth muscle (dVSM). In the present study, we show that contractile agonists increase the net polymerization of actin in dVSM, as measured by the differential ultracentrifugation of vascular smooth muscle tissue and the costaining of single freshly dissociated cells with fluorescent probes specific for globular and filamentous actin. Furthermore, induced alterations of the actin polymerization state, as well as actin decoy peptides, inhibit contractility in a stimulus-dependent manner. Latrunculin pretreatment or actin decoy peptides significantly inhibit contractility induced by a phorbol ester or an alpha-agonist, but these procedures have no effect on contractions induced by KCl. Aorta dVSM expresses alpha-smooth muscle actin, beta-actin, nonmuscle gamma-actin, and smooth muscle gamma-actin. The incorporation of isoform-specific cell-permeant synthetic actin decoy peptides, as well as isoform-specific probing of cell fractions and two-dimensional gels, demonstrates that actin remodeling during alpha-agonist contractions involves the remodeling of primarily gamma-actin and, to a lesser extent, beta-actin. Taken together, these results show that net isoform- and agonist-dependent increases in actin polymerization regulate vascular contractility.
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Affiliation(s)
- Hak Rim Kim
- Department of Health Sciences, Boston University, Boston, Massachusetts 02215, USA
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27
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Dougherty PJ, Davis MJ, Zawieja DC, Muthuchamy M. Calcium sensitivity and cooperativity of permeabilized rat mesenteric lymphatics. Am J Physiol Regul Integr Comp Physiol 2008; 294:R1524-32. [PMID: 18305021 DOI: 10.1152/ajpregu.00888.2007] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Lymphatic muscle contraction is critical for the centripetal movement of lymph that regulates fluid balance, protein homeostasis, lipid absorption, and immune function. We have demonstrated that lymphatic muscle has both smooth and striated muscle contractile elements; however, the basic contractile properties of this tissue remain poorly defined. We hypothesized that contractile characteristics of lymphatic myofilaments would be different from vascular smooth muscle myofilaments. To test this hypothesis, -log[Ca(2+)] (pCa)-tension relationship was determined for alpha-toxin permeabilized mesenteric lymphatics, arteries, and veins. The Ca(2+) sensitivity (pCa(50)) of mesenteric lymphatics was significantly lower compared with arteries (6.16 +/- 0.05 vs. 6.44 +/- 0.02; P < 0.05), whereas there was no difference in pCa(50) between lymphatics and veins (6.16 +/- 0.05 vs. 6.00 +/- 0.10; not significant). The Hill coefficient for alpha-toxin-permeabilized lymphatics was not significantly different from arteries but was significantly greater than that of the veins (1.98 +/- 0.19 vs. 1.21 +/- 0.18; P < 0.05). In addition, the maximal tension and pCa(50) values were significantly greater in alpha-toxin-permeabilized lymphatics compared with beta-escin-permeabilized lymphatics (0.27 +/- 0.03 vs. 0.15 +/- 0.01 and 6.16 +/- 0.05 vs. 5.86 +/- 0.06 mN/mm, respectively; P < 0.05), whereas the Hill coefficient was significantly greater in beta-escin-permeabilized lymphatics. Western blot analyses revealed that CPI-17 levels were significantly decreased by about 50% in beta-escin-permeabilized lymphatics, compared with controls, whereas no change in the level of calmodulin was detected. Our data constitute the first description of the pCa-tension relationship in permeabilized lymphatic muscle. It suggests that differences in myofilament Ca(2+) sensitivity and cooperativity among lymphatic muscle and vascular smooth muscles contribute to the functional differences that exist between these tissues.
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Affiliation(s)
- Patrick J Dougherty
- Department of Systems Biology and Translational Medicine, Texas A&M Health Science Center College of Medicine, College Station, TX, USA
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Carruthers NJ, Stemmer PM. Methionine oxidation in the calmodulin-binding domain of calcineurin disrupts calmodulin binding and calcineurin activation. Biochemistry 2008; 47:3085-95. [PMID: 18275158 DOI: 10.1021/bi702044x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Calcineurin is a Ca (2+)/calmodulin-activated Ser/Thr phosphatase important in cellular actions resulting in memory formation, cardiac hypertrophy, and T-cell activation. This enzyme is subject to oxidative inactivation by superoxide at low micromolar concentrations and by H 2O 2 at low millimolar concentrations. On the basis of the hypothesis that oxidation of Met residues in calmodulin-binding domains inhibits binding to calmodulin, purified calcineurin was used to study the susceptibility of Met residues to oxidation by H 2O 2. The rate for oxidation of Met 406 in the calmodulin-binding domain was determined to be 4.4 x 10 (-3) M (-1) s (-1), indicating a high susceptibility to oxidation. Functional repercussions of Met 406 oxidation were evaluated using native enzyme and a calcineurin mutant in which Met 406 was exchanged for Leu. Measurement of fluorescent calmodulin binding demonstrated that oxidation of Met 406 results in a 3.3-fold decrease in the affinity of calmodulin for calcineurin. Calcineurin activation exhibited a loss in cooperativity with respect to calmodulin following Met 406 oxidation as shown by a reduction in the Hill slope from 1.88 to 0.86. Maximum phosphatase activity was unaffected by Met oxidation. Changes in the calcineurin-calmodulin interaction were accompanied by a 40% loss in the ability of calmodulin to stimulate binding of immunophilin/immunosuppressant to calcineurin. All effects on calmodulin binding to the native enzyme by the treatment with H 2O 2 could be reversed by treating the enzyme with methionine sulfoxide reductase. These results indicate that the calmodulin-binding domain of calcineurin is susceptible to oxidation at Met 406 and that oxidation disrupts calmodulin binding and enzyme activation. Oxidation-dependent decreases in the affinity of calmodulin for calcineurin can potentially modulate calmodulin-dependent signaling and calmodulin distribution.
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Affiliation(s)
- Nicholas J Carruthers
- Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan 48201, USA
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Yang HQ, Pan J, Ba MW, Sun ZK, Ma GZ, Lu GQ, Xiao Q, Chen SD. New protein kinase C activator regulates amyloid precursor protein processing in vitro by increasing alpha-secretase activity. Eur J Neurosci 2007; 26:381-91. [PMID: 17650113 DOI: 10.1111/j.1460-9568.2007.05648.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The beta amyloid (Abeta) cascade has been at the forefront of the hypothesis used to describe the pathogenesis of Alzheimer's disease (AD). It is generally accepted that drugs that can regulate the processing of the amyloid precursor protein (APP) toward the non-amyloidogenic pathway may have a therapeutic potential. Previous studies have shown that protein kinase C (PKC) hypofunction has an important role in AD pathophysiology. Therefore, the effects of a new PKC activator, alpha-APP modulator [(2S,5S)-(E,E)-8-(5-(4-(trifluoromethyl)phenyl)-2,4-pentadienoylamino)benzolactam (TPPB)], on APP processing were investigated. Using PC12 cells and SH-SY5Y(APP695) cells, it was found that TPPB promoted the secretion of sAPPalpha without affecting full-length expression of APP. The increase in sAPPalpha by TPPB was blocked by inhibitors of PKC, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) and tyrosine kinase, suggesting the involvement of these signal transduction pathways. TPPB increased alpha-secretase activity [a disintegrin and metalloproteinase (ADAM)10 and 17], as shown by direct fluorescence activity detection and Western blot analysis. TPPB-induced sAPPalpha release was blocked by the metalloproteinase inhibitor TAPI-2, furin inhibitor CMK and by the protein-trafficking inhibitor brefeldin. The results also showed that TPPB decreased beta-secretase activity, Abeta40 release and beta site APP-cleaving enzyme 1 (BACE1) expression, but did not significantly affect neprilysin (NEP) and insulin-degrading enzyme (IDE) expression. Our data indicate that TPPB could direct APP processing towards the non-amyloidogenic pathway by increasing alpha-secretase activity, and suggest its therapeutic potential in AD.
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Affiliation(s)
- Hong-Qi Yang
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai JiaoTong University School of Medicine, Shanghai 200025, P.R. China
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Li Y, Gallant C, Malek S, Morgan KG. Focal adhesion signaling is required for myometrial ERK activation and contractile phenotype switch before labor. J Cell Biochem 2007; 100:129-40. [PMID: 16888778 DOI: 10.1002/jcb.21033] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
In late pregnancy rapidly increasing fetal growth dramatically increases uterine wall tension. This process has been implicated in the activation of the myometrium for labor, but the mechanisms involved are unclear. Here, we tested, using a rat model, the hypothesis that gestation-dependent stretch, via activation of focal adhesion signaling, contributes to the published activation of myometrial ERK at the end of pregnancy. Consistent with this hypothesis, we show here that ERK is targeted to adhesion plaques during late pregnancy. Furthermore, myometrial stretch triggers a dramatic increase in myometrial contractility and ERK and caldesmon phosphorylation, confirming the presence of stretch sensitive myometrial signaling element. Screening by anti-phosphotyrosine immunoblotting for focal adhesion signaling in response to stretch reveals a significant increase in the tyrosine phosphorylated bands identified as focal adhesion kinase (FAK), A-Raf, paxillin, and Src. Pretreatment with PP2, a Src inhibitor, significantly suppresses the stretch-induced increases in FAK, paxillin, Src, ERK and caldesmon phosphorylation and myometrial contractility. Thus, focal adhesion-Src signaling contributes to ERK activation and promotes contraction in late pregnancy. These results point to focal adhesion signaling molecules as potential targets in the modulation of the myometrial contractility and the onset of labor.
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Affiliation(s)
- Yunping Li
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA.
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Shiraishi M, Tanabe A, Saito N, Sasaki Y. Unphosphorylated MARCKS is involved in neurite initiation induced by insulin-like growth factor-I in SH-SY5Y cells. J Cell Physiol 2007; 209:1029-38. [PMID: 16941482 DOI: 10.1002/jcp.20814] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Myristoylated alanine-rich C kinase substrate (MARCKS) has been suggested to be involved in various aspects of neuronal cell differentiation, including neurite outgrowth. However, the precise mechanisms by which MARCKS phosphorylation is regulated, and how MARCKS contributes to neurite outgrowth, are poorly understood. Here, we found that treatment of SH-SY5Y cells with insulin-like growth factor-I (IGF-I) induced a rapid and transient decrease in the level of phosphorylated MARCKS (P-MARCKS) to below the basal level. The decrease in P-MARCKS induced by IGF-I was blocked by pretreatment of cells with phosphoinositide 3-kinase (PI3K) inhibitors, LY294002 and wortmannin. A decrease in P-MARCKS was also observed in cells treated with a Rho-dependent kinase (ROCK) inhibitor, Y27632. Furthermore, IGF-I induced transient inactivation of RhoA, an upstream effector of ROCK. We showed that MARCKS was translocated to the membrane and colocalized with F-actin at the lamellipodia and the tips of neurites in the cells stimulated with IGF-I. Finally, overexpression of wild-type MARCKS or an unphosphorylatable mutant of MARCKS enhanced the number of neurite-bearing cells relative to vector-transfected cells. Taken together, these findings suggest that unphosphorylated MARCKS is involved in neurite initiation, and highlight the important role played by MARCKS in organization of the actin cytoskeleton.
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Affiliation(s)
- Mitsuya Shiraishi
- Laboratory of Pharmacology, School of Pharmaceutical Science, Kitasato University, Shirokane 5-9-1, Minato-ku, Tokyo 108-8641, Japan.
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Yang HQ, Ba MW, Ren RJ, Zhang YH, Ma JF, Pan J, Lu GQ, Chen SD. Mitogen activated protein kinase and protein kinase C activation mediate promotion of sAPPα secretion by deprenyl. Neurochem Int 2007; 50:74-82. [PMID: 16973242 DOI: 10.1016/j.neuint.2006.07.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2006] [Revised: 06/29/2006] [Accepted: 07/10/2006] [Indexed: 12/14/2022]
Abstract
The beta amyloid cascade plays a crucial role in the pathogenesis of Alzheimer's disease (AD). Therefore, drugs that regulate amyloid precursor protein (APP) processing toward the nonamyloidgenic pathway may have therapeutic potential. Many anti-dementia drugs can regulate APP processing in addition to their pharmacological properties. Deprenyl is a neuroprotective agent used to treat some neurodegenerative diseases, including AD. In the present study, the effects of deprenyl on APP processing were investigated. Using SK-N-SH and PC12 cells, it was demonstrated that deprenyl stimulated the release of the nonamyloidogenic alpha-secretase form of soluble APP (sAPPalpha) in a dose-dependent manner without affecting cellular APP expression. The increase of sAPPalpha secretion by deprenyl was blocked by the mitogen activated protein (MAP) kinase inhibitor U0126 and PD98059, and by the protein kinase C (PKC) inhibitor GF109203X and staurosporine, suggesting the involvement of these signal transduction pathways. Deprenyl induced phosphorylation of p42/44 MAP kinase, which was abolished by specific inhibitors of MAP kinase and PKC. Deprenyl also phosphorylated PKC and its major substrate, and myristoylated alanine-rich C kinase (MARCKS) at specific amino acid residues. The data also indicated that 10microM deprenyl successfully induced two PKC isoforms involved in the pathogenesis of AD, PKCalpha and PKCepsilon, to translocate from the cytosolic to the membrane fraction. This phenomenon was substantiated by immunocytochemistry staining. These data suggest a novel pharmacological mechanism in which deprenyl regulates the processing of APP via activation of the MAP kinase and PKC pathways, and that this mechanism may underlie the clinical efficacy of the drug in some AD patients.
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Affiliation(s)
- Hong-Qi Yang
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, PR China
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