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Landini L, Dadson P, Gallo F, Honka MJ, Cena H. Microbiota in anorexia nervosa: potential for treatment. Nutr Res Rev 2023; 36:372-391. [PMID: 35875979 DOI: 10.1017/s0954422422000130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Anorexia nervosa (AN) is characterised by the restriction of energy intake in relation to energy needs and a significantly lowered body weight than normally expected, coupled with an intense fear of gaining weight. Treatment of AN is currently based on psychological and refeeding approaches, but their efficacy remains limited since 40% of patients after 10 years of medical care still present symptoms of AN. The intestine hosts a large community of microorganisms, called the "microbiota", which live in symbiosis with the human host. The gut microbiota of a healthy human is dominated by bacteria from two phyla: Firmicutes and, majorly, Bacteroidetes. However, the proportion in their representation differs on an individual basis and depends on many external factors including medical treatment, geographical location and hereditary, immunological and lifestyle factors. Drastic changes in dietary intake may profoundly impact the composition of the gut microbiota, and the resulting dysbiosis may play a part in the onset and/or maintenance of comorbidities associated with AN, such as gastrointestinal disorders, anxiety and depression, as well as appetite dysregulation. Furthermore, studies have reported the presence of atypical intestinal microbial composition in patients with AN compared with healthy normal-weight controls. This review addresses the current knowledge about the role of the gut microbiota in the pathogenesis and treatment of AN. The review also focuses on the bidirectional interaction between the gastrointestinal tract and the central nervous system (microbiota-gut-brain axis), considering the potential use of the gut microbiota manipulation in the prevention and treatment of AN.
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Affiliation(s)
- Linda Landini
- S.S.D. Dietetics and Clinical Nutrition ASL 4 Chiavarese Liguria-Sestri Levante Hospital, Sestri Levante, Italy
| | - Prince Dadson
- Turku PET Centre, University of Turku, Turku, Finland
| | - Fabrizio Gallo
- S.S.D. Dietetics and Clinical Nutrition ASL 4 Chiavarese Liguria-Sestri Levante Hospital, Sestri Levante, Italy
| | | | - Hellas Cena
- Dietetics and Clinical Nutrition Laboratory, Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy
- Clinical Nutrition and Dietetics Service, Unit of Internal Medicine and Endocrinology, ICS Maugeri IRCCS, Pavia, Italy
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Kuzmina IV, Ovchinnikova NV, Tolpygo SM. Serum Activity of Proteolytic Enzyme Trypsin in Rats under Conditions of Water and Food Deprivation. Bull Exp Biol Med 2023; 175:608-611. [PMID: 37861909 DOI: 10.1007/s10517-023-05910-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Indexed: 10/21/2023]
Abstract
Trypsin is mainly regarded as a digestive enzyme, but there is evidence that activation of protease-activated receptor-2 (PAR-2) leads to behavioral changes. There are no data on trypsin activity in the serum of animals under conditions of thirst and starvation in the available literature. In our experiments, water deprivation led to a significant (p⩽0.05) increase in trypsin activity in rats, and food deprivation led to its decrease in comparison with controls (free access to water and food). After deprived rats received water and food, a decrease in trypsin activity was observed in both experimental groups. Changes in trypsin activity under conditions of water or food deprivation and after satiation were accompanied by shifts in some biochemical parameters of the bloods. Under conditions of metabolic stress (starvation and thirst), opposite changes in trypsin activity seem to indicate its participation in the mechanisms of adequate restructuring of metabolism and maintenance of vital processes in the body.
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Affiliation(s)
- I V Kuzmina
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia.
| | - N V Ovchinnikova
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
| | - S M Tolpygo
- P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia
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Carvalho R, Bonfá IS, de Araújo Isaías Muller J, Pando SC, Toffoli-Kadri MC. Protease inhibitor from Libidibia ferrea seeds attenuates inflammatory and nociceptive responses in mice. JOURNAL OF ETHNOPHARMACOLOGY 2023; 300:115694. [PMID: 36096346 DOI: 10.1016/j.jep.2022.115694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 08/15/2022] [Accepted: 08/31/2022] [Indexed: 06/15/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Libidibia ferrea (Mart. ex. Tul.) L.P. Queiroz is a Brazilian native tree locally known as jucá and pau-ferro, and it has been used in folk medicine for relieving, asthma, bronchitis, sore throat, rheumatism, enterocolitis and fever. The anti-inflammatory properties of L. ferrea were confirmed for its stem, fruit, leaves, bark and seeds extracts, however little is known about the natural compounds that may be associated with that response. AIM OF THIS STUDY In a normal physiological condition, many enzymes play an important role in catalyzing biological functions. Among them, proteases are of great interest. Although they take part of many biological systems, as the inflammatory process, when deregulated, proteases may cause system malfunctions, such as under- or overproduction of cytokines, or immune cells activation. Thus, protease inhibitors prevent these immune responses by regulating proteases. The objective of this study was to evaluate the anti-inflammatory and anti-nociceptive response of a protease inhibitor purified from L. ferrea seeds (LfTI). MATERIALS AND METHODS In vitro (5, 50 and 250 μg/mL of LfTI) and in vivo (0.6, 3 e 15 mg/kg of LfTI) assays were performed. Male Swiss mice weighing 18-25 g were used for cell harvesting and for the in vivo assays. The anti-inflammatory activity was analyzed in vitro by macrophage cytotoxicity, hydrogen peroxide (H2O2) production, and cell adhesion assays; and in vivo by leukocyte recruitment, nitric oxide (NO) production, vascular permeability, paw edema and mast cell degranulation assays. The anti-nociceptive activity was evaluated through abdominal writhing test induced by acetic acid and formalin sensitization. RESULTS Our results showed that, in vitro, LfTI is not cytotoxic. Also, LfTI (50 μg/mL) inhibited macrophage H2O2 production (48.2%), and adhesion (48.4%). LfTI (0.6, 3 e 15 mg/kg) decreased polymorphonuclear cell recruitment dose-dependently, and it inhibited NO production (53%), vascular permeability (40.7%) and paw edema at 3 mg/kg at different time, but it did not inhibit mast cell degranulation. Besides, LfTI did not inhibit either the number of writhing or the licking time in the formalin test in the second phase (inflammatory). However, LfTI (3 mg/kg) inhibited licking time at the first phase (neurogenic) in the formalin sensitization (46.1%). CONCLUSIONS Our results show that LfTI has anti-inflammatory and antinociceptive (neurogenic pain) effects, and these effects might be associated with the inhibition of inflammatory proteases and/or protease-activated receptors activation hindering.
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Affiliation(s)
- Raquel Carvalho
- Graduate Program in Biotechnology, Faculty of Pharmaceutical Sciences, Food and Nutrition, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, MS, Brazil; Laboratory of Pharmacology and Inflammation, Faculty of Pharmaceutical Sciences, Food and Nutrition, UFMS, Campo Grande, MS, Brazil.
| | - Iluska Senna Bonfá
- Laboratory of Pharmacology and Inflammation, Faculty of Pharmaceutical Sciences, Food and Nutrition, UFMS, Campo Grande, MS, Brazil.
| | - Jéssica de Araújo Isaías Muller
- Laboratory of Pharmacology and Inflammation, Faculty of Pharmaceutical Sciences, Food and Nutrition, UFMS, Campo Grande, MS, Brazil; Multicenter Graduate Program in Biochemistry and Molecular Biology, Institute of Biosciences, UFMS, Campo Grande, MS, Brazil.
| | | | - Mônica Cristina Toffoli-Kadri
- Graduate Program in Biotechnology, Faculty of Pharmaceutical Sciences, Food and Nutrition, Federal University of Mato Grosso do Sul (UFMS), Campo Grande, MS, Brazil; Laboratory of Pharmacology and Inflammation, Faculty of Pharmaceutical Sciences, Food and Nutrition, UFMS, Campo Grande, MS, Brazil; Multicenter Graduate Program in Biochemistry and Molecular Biology, Institute of Biosciences, UFMS, Campo Grande, MS, Brazil.
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Jiang Y, Lim J, Wu KC, Xu W, Suen JY, Fairlie DP. PAR2 induces ovarian cancer cell motility by merging three signalling pathways to transactivate EGFR. Br J Pharmacol 2020; 178:913-932. [PMID: 33226635 DOI: 10.1111/bph.15332] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 11/08/2020] [Accepted: 11/14/2020] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND AND PURPOSE Specific cellular functions mediated by GPCRs are often associated with signalling through a particular G protein or β-arrestin. Here, we examine signalling through a GPCR, protease-activated receptor 2 (PAR2), in a high-grade serous ovarian cancer cell line (OV90). EXPERIMENTAL APPROACH Human ovarian cancer tissues (n = 1,200) and nine human ovarian cancer cell lines were assessed for PAR2 expression. PAR2 signalling mechanisms leading to cell migration and invasion were dissected using cellular assays, western blots, CRISPR-Cas9 gene knockouts, pharmacological inhibitors of PAR2 and downstream signalling proteins in OV90 cancer cells. KEY RESULTS PAR2 was significantly overexpressed in clinical ovarian cancer tissues and in OV90 ovarian cancer cells. PAR2 agonists, an endogenous protease (trypsin) and a synthetic peptide (2f-LIGRL-NH2 ), induced migration and invasion of OV90 ovarian cancer cells through activating a combination of Gαq/11 , Gα12/13 and β-arrestin1/2, but not Gαs or Gαi . This novel cooperative rather than parallel signalling resulted in downstream serial activation of Src kinases, then transactivation of epidermal growth factor receptor (EGFR), followed by downstream MEK-ERK1/2-FOS/MYC/STAT3-COX2 signalling. Either a PAR2 antagonist (I-191), CRISPR-Cas9 gene knockouts (PAR2 or Gα proteins or β-arrestin1/2), or inhibitors of each downstream protein attenuated human ovarian cancer cell motility. CONCLUSION AND IMPLICATIONS This study highlights a novel shared signalling cascade, requiring each of Gαq/11 , Gα12/13 and β-arrestin1/2 for PAR2-induced ovarian cancer cell migration and invasion. This mechanism controlling a cellular function is unusual in not being linked to a specific individual G protein or β-arrestin-mediated signalling pathway.
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Affiliation(s)
- Yuhong Jiang
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Junxian Lim
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Kai-Chen Wu
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Weijun Xu
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Jacky Y Suen
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - David P Fairlie
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
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Kumar JBS, Sharma B. A review on neuropharmacological role of erucic acid: an omega-9 fatty acid from edible oils. Nutr Neurosci 2020; 25:1041-1055. [PMID: 33054628 DOI: 10.1080/1028415x.2020.1831262] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Neurodegenerative diseases (ND) are characterised by loss of neurons in the brain and spinal cord. For the normal functioning of the brain, divers group of fatty acids in the form of glycerophospholipids, glycerol ether lipids, cerebrosides, sulfatides, and gangliosides are essential. They are present abundantly in the nervous system and are actively involved in both the development and maintenance of the nervous system. A dietary deficiency of essential fatty acid during development results in hypomyelination state which affects various neuronal functions. Several studies suggested that age remains the primary risk factor for almost all neurodegenerative disorders. The potential contribution of these fatty acids in the progression of neurodegenerative disorders is indispensable. Erucic acid an omega 9 fatty acid, which is obtained from edible oils has proven to cause myocardial lipidosis, heart lesions and hepatic steatosis in animals therefore, its content in edible oils is restricted to certain levels by regulatory agencies. However, erucic acid in the form of a mixture with oleic acid is often used as a dietary treatment for the management of adrenoleukodystrophy without any cardiotoxicity. Our literature search revealed that, erucic acid reported to enhance cognitive function, interact with peroxisome proliferator activated receptors (PPARs), inhibit elastase and thrombin. In this review first we have attempted to describe the relationship between fatty acids and neurodegeneration followed by a description on the pharmacology of erucic acid. The overall purpose of this review is to analyse toxic and beneficial neuropharmacological effects of erucic acid.
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Affiliation(s)
- J B Senthil Kumar
- Special centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India.,School of Medical and Allied Sciences, KR Mangalam University, Delhi NCR, India
| | - Bhawna Sharma
- School of Medical and Allied Sciences, KR Mangalam University, Delhi NCR, India
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Identification of Potential Key Genes and Pathways in Enzalutamide-Resistant Prostate Cancer Cell Lines: A Bioinformatics Analysis with Data from the Gene Expression Omnibus (GEO) Database. BIOMED RESEARCH INTERNATIONAL 2020; 2020:8341097. [PMID: 32724813 PMCID: PMC7382728 DOI: 10.1155/2020/8341097] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 06/03/2020] [Accepted: 06/20/2020] [Indexed: 12/15/2022]
Abstract
Enzalutamide (ENZ) has been approved for the treatment of advanced prostate cancer (PCa), but some patients develop ENZ resistance initially or after long-term administration. Although a few key genes have been discovered by previous efforts, the complete mechanisms of ENZ resistance remain unsolved. To further identify more potential key genes and pathways in the development of ENZ resistance, we employed the GSE104935 dataset, including 5 ENZ-resistant (ENZ-R) and 5 ENZ-sensitive (ENZ-S) PCa cell lines, from the Gene Expression Omnibus (GEO) database. Integrated bioinformatics analyses were conducted, such as analysis of differentially expressed genes (DEGs), Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, protein-protein interaction (PPI) analysis, gene set enrichment analysis (GSEA), and survival analysis. From these, we identified 201 DEGs (93 upregulated and 108 downregulated) and 12 hub genes (AR, ACKR3, GPER1, CCR7, NMU, NDRG1, FKBP5, NKX3-1, GAL, LPAR3, F2RL1, and PTGFR) that are potentially associated with ENZ resistance. One upregulated pathway (hedgehog pathway) and seven downregulated pathways (pathways related to androgen response, p53, estrogen response, TNF-α, TGF-β, complement, and pancreas β cells) were identified as potential key pathways involved in the occurrence of ENZ resistance. Our findings may contribute to further understanding the molecular mechanisms of ENZ resistance and provide some clues for the prevention and treatment of ENZ resistance.
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Alim MA, Peterson M, Pejler G. Do Mast Cells Have a Role in Tendon Healing and Inflammation? Cells 2020; 9:cells9051134. [PMID: 32375419 PMCID: PMC7290807 DOI: 10.3390/cells9051134] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 04/29/2020] [Accepted: 04/30/2020] [Indexed: 12/15/2022] Open
Abstract
Understanding the links between the tendon healing process, inflammatory mechanisms, and tendon homeostasis/pain after tissue damage is crucial in developing novel therapeutics for human tendon disorders. The inflammatory mechanisms that are operative in response to tendon injury are not fully understood, but it has been suggested that inflammation occurring in response to nerve signaling, i.e., neurogenic inflammation, has a pathogenic role. The mechanisms driving such neurogenic inflammation are presently not clear. However, it has recently been demonstrated that mast cells present within the injured tendon can express glutamate receptors, raising the possibility that mast cells may be sensitive to glutamate signaling and thereby modulate neurogenic inflammation following tissue injury. In this review, we discuss the role of mast cells in the communication with peripheral nerves, and their emerging role in tendon healing and inflammation after injury.
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Affiliation(s)
- Md Abdul Alim
- Department of Public Health and Caring Sciences, General Medicine, Uppsala University, 751 22 Uppsala, Sweden;
- Department of Medical Biochemistry and Microbiology, Uppsala University, 75123 Uppsala, Sweden
- Correspondence: (M.A.A.); (G.P.)
| | - Magnus Peterson
- Department of Public Health and Caring Sciences, General Medicine, Uppsala University, 751 22 Uppsala, Sweden;
- Academic Primary Health Care, Region Uppsala, Sweden
| | - Gunnar Pejler
- Department of Medical Biochemistry and Microbiology, Uppsala University, 75123 Uppsala, Sweden
- Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, 756 51 Uppsala, Sweden
- Correspondence: (M.A.A.); (G.P.)
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Photoactivatable fluorescent probes for spatiotemporal-controlled biosensing and imaging. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2020.115811] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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10
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Sinagra E, Utzeri E, Morreale GC, Fabbri C, Pace F, Anderloni A. Microbiota-gut-brain axis and its affect inflammatory bowel disease: Pathophysiological concepts and insights for clinicians. World J Clin Cases 2020; 8:1013-1025. [PMID: 32258072 PMCID: PMC7103973 DOI: 10.12998/wjcc.v8.i6.1013] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 02/14/2020] [Accepted: 03/05/2020] [Indexed: 02/05/2023] Open
Abstract
Despite the bi-directional interaction between gut microbiota and the brain not being fully understood, there is increasing evidence arising from animal and human studies that show how this intricate relationship may facilitate inflammatory bowel disease (IBD) pathogenesis, with consequent important implications on the possibility to improve the clinical outcomes of the diseases themselves, by acting on the different components of this system, mainly by modifying the microbiota. With the emergence of precision medicine, strategies in which patients with IBD might be categorized other than for standard gut symptom complexes could offer the opportunity to tailor therapies to individual patients. The aim of this narrative review is to elaborate on the concept of the gut-brain-microbiota axis and its clinical significance regarding IBD on the basis of recent scientific literature, and finally to focus on pharmacological therapies that could allow us to favorably modify the function of this complex system.
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Affiliation(s)
- Emanuele Sinagra
- Gastroenterology and Endoscopy Unit, Fondazione Istituto Giuseppe Giglio, Contrada Pietra Pollastra Pisciotto, Cefalù 90015, Italy
- Euro-Mediterranean Institute of Science and Technology, Palermo 90100, Italy
| | - Erika Utzeri
- Nuova Casa di Cura di Decimomannu, Cagliari 09100, Italy
| | | | - Carlo Fabbri
- Gastroenterology and Digestive Endoscopy Unit, Forlì-Cesena, Azienda USL Romagna, Forlì 47121, Italy
| | - Fabio Pace
- Unit of Gastroenterology, Bolognini Hospital, Bergamo 24100, Italy
| | - Andrea Anderloni
- Digestive Endoscopy Unit, Division of Gastroenterology, Humanitas Research Hospital, Rozzano 20089, Italy
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Kempuraj D, Selvakumar GP, Thangavel R, Ahmed ME, Zaheer S, Kumar KK, Yelam A, Kaur H, Dubova I, Raikwar SP, Iyer SS, Zaheer A. Glia Maturation Factor and Mast Cell-Dependent Expression of Inflammatory Mediators and Proteinase Activated Receptor-2 in Neuroinflammation. J Alzheimers Dis 2019; 66:1117-1129. [PMID: 30372685 DOI: 10.3233/jad-180786] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Parkinson's disease (PD) is characterized by the presence of inflammation-mediated dopaminergic neurodegeneration in the substantia nigra. Inflammatory mediators from activated microglia, astrocytes, neurons, T-cells and mast cells mediate neuroinflammation and neurodegeneration. Administration of neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induces PD like motor deficits in rodents. 1-methyl-4-phenylpyridinium (MPP+), a toxic metabolite of MPTP activates glial cells, neurons and mast cells to release neuroinflammatory mediators. Glia maturation factor (GMF), mast cells and proteinase activated receptor-2 (PAR-2) are implicated in neuroinflammation. Alpha-synuclein which induces neurodegeneration increases PAR-2 expression in the brain. However, the exact mechanisms are not yet understood. In this study, we quantified inflammatory mediators in the brains of MPTP-administered wild type (Wt), GMF-knockout (GMF-KO), and mast cell knockout (MC-KO) mice. Additionally, we analyzed the effect of MPP+, GMF, and mast cell proteases on PAR-2 expression in astrocytes and neurons in vitro. Results show that the levels of interleukin-1beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and the chemokine (C-C motif) ligand 2 (CCL2) were lesser in the brains of GMF-KO mice and MC-KO mice when compared to Wt mice brain after MPTP administration. Incubation of astrocytes and neurons with MPP+, GMF, and mouse mast cell protease-6 (MMCP-6) and MMCP-7 increased the expression of PAR-2. Our studies show that the absence of mast cells and GMF reduce the expression of neuroinflammatory mediators in the brain. We conclude that GMF along with mast cell interactions with glial cells and neurons during neuroinflammation can be explored as a new therapeutic target for PD and other neuroinflammatory disorders.
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Affiliation(s)
- Duraisamy Kempuraj
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA.,Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Govindhasamy Pushpavathi Selvakumar
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA.,Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Ramasamy Thangavel
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA.,Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Mohammad Ejaz Ahmed
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA.,Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Smita Zaheer
- Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Keerthana Kuppamma Kumar
- Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Anudeep Yelam
- Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Harleen Kaur
- Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Iuliia Dubova
- Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Sudhanshu P Raikwar
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA.,Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Shankar S Iyer
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA.,Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Asgar Zaheer
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA.,Department of Neurology, and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Columbia, MO, USA
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Kempuraj D, Thangavel R, Selvakumar GP, Ahmed ME, Zaheer S, Raikwar SP, Zahoor H, Saeed D, Dubova I, Giler G, Herr S, Iyer SS, Zaheer A. Mast Cell Proteases Activate Astrocytes and Glia-Neurons and Release Interleukin-33 by Activating p38 and ERK1/2 MAPKs and NF-κB. Mol Neurobiol 2018; 56:1681-1693. [PMID: 29916143 DOI: 10.1007/s12035-018-1177-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/04/2018] [Indexed: 12/13/2022]
Abstract
Inflammatory mediators released from activated microglia, astrocytes, neurons, and mast cells mediate neuroinflammation. Parkinson's disease (PD) is characterized by inflammation-dependent dopaminergic neurodegeneration in substantia nigra. 1-Methyl-4-phenylpyridinium (MPP+), a metabolite of parkinsonian neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), induces inflammatory mediators' release from brain cells and mast cells. Brain cells' interaction with mast cells is implicated in neuroinflammation. However, the exact mechanisms involved are not yet clearly understood. Mouse fetal brain-derived cultured primary astrocytes and glia-neurons were incubated with mouse mast cell protease-6 (MMCP-6) and MMCP-7, and mouse bone marrow-derived mast cells (BMMCs) were incubated with MPP+ and brain protein glia maturation factor (GMF). Interleukin-33 (IL-33) released from these cells was quantitated by enzyme-linked immunosorbent assay. Both MMCP-6 and MMCP-7 induced IL-33 release from astrocytes and glia-neurons. MPP+ and GMF were used as a positive control-induced IL-33 and reactive oxygen species expression in mast cells. Mast cell proteases and MPP+ activate p38 and extracellular signal-regulated kinases 1/2 (ERK1/2), mitogen-activated protein kinases (MAPKs), and transcription factor nuclear factor-kappa B (NF-κB) in astrocytes, glia-neurons, or mast cells. Addition of BMMCs from wt mice and transduction with adeno-GMF show higher chemokine (C-C motif) ligand 2 (CCL2) release. MPP+ activated glial cells and reduced microtubule-associated protein 2 (MAP-2) expression indicating neurodegeneration. IL-33 expression increased in the midbrain and striatum of PD brains as compared with age- and sex-matched control subjects. Glial cells and neurons interact with mast cells and accelerate neuroinflammation and these interactions can be explored as a new therapeutic target to treat PD.
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Affiliation(s)
- Duraisamy Kempuraj
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA.
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA.
| | - Ramasamy Thangavel
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Gvindhasamy Pushpavathi Selvakumar
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Mohammad Ejaz Ahmed
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Smita Zaheer
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Sudhanshu P Raikwar
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Haris Zahoor
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Daniyal Saeed
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Iuliia Dubova
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Gema Giler
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Shelby Herr
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Shankar S Iyer
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA
| | - Asgar Zaheer
- Harry S. Truman Memorial Veterans Hospital, U.S. Department of Veterans Affairs, Columbia, MO, USA.
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, Medical Science Building,1 Hospital Drive, Columbia, MO, 65211, USA.
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13
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Chamessian A, Young M, Qadri Y, Berta T, Ji RR, Van de Ven T. Transcriptional Profiling of Somatostatin Interneurons in the Spinal Dorsal Horn. Sci Rep 2018; 8:6809. [PMID: 29717160 PMCID: PMC5931607 DOI: 10.1038/s41598-018-25110-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 04/13/2018] [Indexed: 01/08/2023] Open
Abstract
The spinal dorsal horn (SDH) is comprised of distinct neuronal populations that process different somatosensory modalities. Somatostatin (SST)-expressing interneurons in the SDH have been implicated specifically in mediating mechanical pain. Identifying the transcriptomic profile of SST neurons could elucidate the unique genetic features of this population and enable selective analgesic targeting. To that end, we combined the Isolation of Nuclei Tagged in Specific Cell Types (INTACT) method and Fluorescence Activated Nuclei Sorting (FANS) to capture tagged SST nuclei in the SDH of adult male mice. Using RNA-sequencing (RNA-seq), we uncovered more than 13,000 genes. Differential gene expression analysis revealed more than 900 genes with at least 2-fold enrichment. In addition to many known dorsal horn genes, we identified and validated several novel transcripts from pharmacologically tractable functional classes: Carbonic Anhydrase 12 (Car12), Phosphodiesterase 11 A (Pde11a), and Protease-Activated Receptor 3 (F2rl2). In situ hybridization of these novel genes showed differential expression patterns in the SDH, demonstrating the presence of transcriptionally distinct subpopulations within the SST population. Overall, our findings provide new insights into the gene repertoire of SST dorsal horn neurons and reveal several novel targets for pharmacological modulation of this pain-mediating population and treatment of pathological pain.
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Affiliation(s)
- Alexander Chamessian
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina, 27710, USA. .,Medical Scientist Training Program, Duke University School of Medicine, Durham, North Carolina, 27710, USA. .,Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina, 27710, USA.
| | - Michael Young
- Department of Neurobiology, Duke University Medical Center, Durham, North Carolina, 27710, USA
| | - Yawar Qadri
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina, 27710, USA
| | - Temugin Berta
- Pain Research Center, Department of Anesthesiology, University of Cincinnati Medical Center, Cincinnati, Ohio, 45267, USA
| | - Ru-Rong Ji
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina, 27710, USA.,Department of Neurobiology, Duke University Medical Center, Durham, North Carolina, 27710, USA
| | - Thomas Van de Ven
- Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina, 27710, USA
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14
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Duan HQ, Wu QL, Yao X, Fan BY, Shi HY, Zhao CX, Zhang Y, Li B, Sun C, Kong XH, Zhou XF, Feng SQ. Nafamostat mesilate attenuates inflammation and apoptosis and promotes locomotor recovery after spinal cord injury. CNS Neurosci Ther 2018; 24:429-438. [PMID: 29352519 DOI: 10.1111/cns.12801] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 12/18/2017] [Accepted: 12/21/2017] [Indexed: 12/23/2022] Open
Abstract
AIM Spinal cord injury (SCI) leads to severe neural damage for which there is currently no effective treatment. Exploration of the neuroprotective effect among clinically approved drugs will speed up clinical translation of SCI. Nafamostat mesilate (NM) as a synthetic serine protease inhibitor has been used clinically in pancreatitis treatments. However, its effectiveness in SCI is unknown. The aim of this study was to confirm the efficacy of NM in ameliorating SCI. METHODS Intraperitoneal administration of NM was performed on a contusion SCI model in Wistar rat. Hematoxylin and eosin staining (H&E staining) and Luxol fast blue (LFB) staining were used to observe the histological lesions. Apoptosis was examined by TUNEL staining, Annexin V-FITC/PI, caspase-3, and Bcl-2. Cytokines and neurotrophins were tested by Western blot. Locomotion recovery assessed by hindlimb BBB score and the inclined plane test. RESULTS Nafamostat mesilate treatment significantly improved locomotion recovery as assessed by hindlimb BBB scores and the inclined plane test. H&E staining and LFB staining showed a significant increase in spared tissue in both gray matter and white matter. NM decreased the expression of the proinflammatory cytokines TNF-α and IL-6. In addition, apoptosis was also significantly decreased, as shown by TUNEL staining and Annexin V-FITC/PI and by Western blotting for caspase-3 and Bcl-2 expression. Due to the mechanism of action of NM as a serine protease inhibitor, the drug decreased thrombin expression in the damaged spinal cord. Furthermore, NM increased the expression of neurotrophins (NT-3, BDNF, and NGF). CONCLUSIONS Upon NM treatment, the functional and histological outcomes were improved, and microenvironment upon SCI was modulated. As a clinically approved drug, NM holds promise for clinical use after spinal cord injury.
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Affiliation(s)
- Hui-Quan Duan
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
| | - Qiu-Li Wu
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
| | - Xue Yao
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
| | - Bao-You Fan
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
| | - Hong-Yu Shi
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
| | - Chen-Xi Zhao
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
| | - Yan Zhang
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
| | - Bo Li
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
| | - Chao Sun
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
| | | | - Xin-Fu Zhou
- School of Pharmacology and Medical Sciences, University of South Australia, Adelaide, SA, Australia
| | - Shi-Qing Feng
- Department of Orthopaedics, National Spinal Cord Injury International Cooperation Base, Tianjin Medical University General Hospital, Tianjin, China
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15
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Jiang Y, Yau MK, Lim J, Wu KC, Xu W, Suen JY, Fairlie DP. A Potent Antagonist of Protease-Activated Receptor 2 That Inhibits Multiple Signaling Functions in Human Cancer Cells. J Pharmacol Exp Ther 2017; 364:246-257. [PMID: 29263243 DOI: 10.1124/jpet.117.245027] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 12/04/2017] [Indexed: 01/15/2023] Open
Abstract
Protease-activated receptor 2 (PAR2) is a cell surface protein linked to G-protein dependent and independent intracellular signaling pathways that produce a wide range of physiological responses, including those related to metabolism, inflammation, pain, and cancer. Certain proteases, peptides, and nonpeptides are known to potently activate PAR2. However, no effective potent PAR2 antagonists have been reported yet despite their anticipated therapeutic potential. This study investigates antagonism of key PAR2-dependent signaling properties and functions by the imidazopyridazine compound I-191 (4-(8-(tert-butyl)-6-(4-fluorophenyl)imidazo[1,2-b]pyridazine-2-carbonyl)-3,3-dimethylpiperazin-2-one) in cancer cells. At nanomolar concentrations, I-191 inhibited PAR2 binding of and activation by structurally distinct PAR2 agonists (trypsin, peptide, nonpeptide) in a concentration-dependent manner in cells of the human colon adenocarcinoma grade II cell line (HT29). I-191 potently attenuated multiple PAR2-mediated intracellular signaling pathways leading to Ca2+ release, extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation, Ras homologue gene family, member A (RhoA) activation, and inhibition of forskolin-induced cAMP accumulation. The mechanism of action of I-191 was investigated using binding and calcium mobilization studies in HT29 cells where I-191 was shown to be noncompetitive and a negative allosteric modulator of the agonist 2f-LIGRL-NH2 The compound alone did not activate these PAR2-mediated pathways, even at high micromolar concentrations, indicating no bias in these signaling properties. I-191 also potently inhibited PAR2-mediated downstream functional responses, including expression and secretion of inflammatory cytokines and cell apoptosis and migration, in human colon adenocarcinoma grade II cell line (HT29) and human breast adenocarcinoma cells (MDA-MB-231). These findings indicate that I-191 is a potent PAR2 antagonist that inhibits multiple PAR2-induced signaling pathways and functional responses. I-191 may be a valuable tool for characterizing PAR2 functions in cancer and in other cellular, physiological, and disease settings.
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Affiliation(s)
- Yuhong Jiang
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
| | - Mei-Kwan Yau
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
| | - Junxian Lim
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
| | - Kai-Chen Wu
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
| | - Weijun Xu
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
| | - Jacky Y Suen
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
| | - David P Fairlie
- Centre for Inflammation and Disease Research and Australian Research Council Centre of Excellence in Advanced Molecular Imaging, Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
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16
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Increased mast cell degranulation and co-localization of mast cells with the NMDA receptor-1 during healing after Achilles tendon rupture. Cell Tissue Res 2017; 370:451-460. [PMID: 28975451 DOI: 10.1007/s00441-017-2684-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 08/23/2017] [Indexed: 10/18/2022]
Abstract
The role of inflammation and the mechanism of tendon healing after rupture has historically been a matter of controversy. The purpose of the present study is to investigate the role of mast cells and their relation to the NMDA receptor-1 (a glutamate receptor) during healing after Achilles tendon rupture. Eight female Sprague Dawley rats had their right Achilles tendon transected. Three weeks after rupture, histological quantification of mast cell numbers and their state of degranulation was assessed by histochemistry. Co-localization of mast cell tryptase (a mast cell marker) and NMDA receptor-1 was determined by immunofluorescence. The intact left Achilles tendon was used as control. An increased number of mast cells and a higher proportion of degranulated mast cells were found in the healing Achilles tendon compared to the intact. In addition, increased co-localization of mast cell tryptase and NMDA receptor-1 was seen in the areas of myotendinous junction, mid-tendon proper and bone tendon junction of the healing versus the intact tendon. These findings introduce a possible role for mast cells in the healing phase after Achilles tendon rupture.
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17
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Kempuraj D, Selvakumar GP, Zaheer S, Thangavel R, Ahmed ME, Raikwar S, Govindarajan R, Iyer S, Zaheer A. Cross-Talk between Glia, Neurons and Mast Cells in Neuroinflammation Associated with Parkinson's Disease. J Neuroimmune Pharmacol 2017; 13:100-112. [PMID: 28952015 DOI: 10.1007/s11481-017-9766-1] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 09/13/2017] [Indexed: 01/28/2023]
Abstract
Parkinson's disease (PD) is a progressive movement disorder characterized by neuroinflammation and dopaminergic neurodegeneration in the brain. 1-methyl-4-phenylpyridinium (MPP+), a metabolite of the parkinsonian neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induces the release of inflammatory mediators from glial cells and neurons. Glia maturation factor (GMF), a brain proinflammatory protein, MPP+, and mast cell-derived inflammatory mediators induce neurodegeneration which eventually leads to PD. However, the precise mechanisms underlying interaction between glial cells, neurons and mast cells in PD still remain elusive. In the present study, mouse bone marrow-derived mast cells (BMMCs) and mouse fetal brain-derived mixed glia/neurons, astrocytes and neurons were incubated with MPP+, GMF and mast cell-derived inflammatory mediators mouse mast cell protease-6 (MMCP-6), MMCP-7 or tryptase/brain-specific serine protease-4 (tryptase/BSSP-4). Inflammatory mediators released from these cells in the culture medium were quantitated by enzyme-linked immunosorbent assay. Neurodegeneration was quantified by measuring total neurite outgrowth following microtubule-associated protein-2 immunocytochemistry. MPP+-induced significant neurodegeneration with reduced total neurite outgrowth. MPP+induced the release of tryptase/BSSP-4 from the mouse mast cells, and tryptase/BSSP-4 induced chemokine (C-C motif) ligand 2 (CCL2) release from astrocytes and glia/neurons. Overall our results suggest that MPP+, GMF, MMCP-6 or MMCP-7 stimulate glia/neurons, astrocytes or neurons to release CCL2 and matrix metalloproteinase-3. Additionally, CD40L expression is increased in BMMCs after incubation with MPP+ in a co-culture system consisting of BMMCs and glia/neurons. We propose that mast cell interaction with glial cells and neurons during neuroinflammation can be explored as a new therapeutic target for PD.
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Affiliation(s)
- Duraisamy Kempuraj
- U.S. Department of Veterans Affairs, Harry S. Truman Memorial Veterans Hospital, Columbia, MO, 65201, USA.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, M741A Medical Science Building, 1 Hospital Drive, Columbia, MO, 65201, USA
| | - Govindhasamy Pushpavathi Selvakumar
- U.S. Department of Veterans Affairs, Harry S. Truman Memorial Veterans Hospital, Columbia, MO, 65201, USA.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, M741A Medical Science Building, 1 Hospital Drive, Columbia, MO, 65201, USA
| | - Smita Zaheer
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, M741A Medical Science Building, 1 Hospital Drive, Columbia, MO, 65201, USA
| | - Ramasamy Thangavel
- U.S. Department of Veterans Affairs, Harry S. Truman Memorial Veterans Hospital, Columbia, MO, 65201, USA.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, M741A Medical Science Building, 1 Hospital Drive, Columbia, MO, 65201, USA
| | - Mohammad Ejaz Ahmed
- U.S. Department of Veterans Affairs, Harry S. Truman Memorial Veterans Hospital, Columbia, MO, 65201, USA.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, M741A Medical Science Building, 1 Hospital Drive, Columbia, MO, 65201, USA
| | - Sudhanshu Raikwar
- U.S. Department of Veterans Affairs, Harry S. Truman Memorial Veterans Hospital, Columbia, MO, 65201, USA.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, M741A Medical Science Building, 1 Hospital Drive, Columbia, MO, 65201, USA
| | - Raghav Govindarajan
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, M741A Medical Science Building, 1 Hospital Drive, Columbia, MO, 65201, USA
| | - Shankar Iyer
- U.S. Department of Veterans Affairs, Harry S. Truman Memorial Veterans Hospital, Columbia, MO, 65201, USA.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, M741A Medical Science Building, 1 Hospital Drive, Columbia, MO, 65201, USA
| | - Asgar Zaheer
- U.S. Department of Veterans Affairs, Harry S. Truman Memorial Veterans Hospital, Columbia, MO, 65201, USA. .,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of Missouri, M741A Medical Science Building, 1 Hospital Drive, Columbia, MO, 65201, USA.
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18
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Bayer SB, Gearry RB, Drummond LN. Putative mechanisms of kiwifruit on maintenance of normal gastrointestinal function. Crit Rev Food Sci Nutr 2017; 58:2432-2452. [PMID: 28557573 DOI: 10.1080/10408398.2017.1327841] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Kiwifruits are recognized as providing relief from constipation and symptoms of constipation-predominant irritable bowel syndrome (IBS-C). However, the underlying mechanisms, specifically in regards to gastrointestinal transit time and motility, are still not completely understood. This review provides an overview on the physiological and pathophysiological processes underlying constipation and IBS-C, the composition of kiwifruit, and recent advances in the research of kiwifruit and abdominal comfort. In addition, gaps in the research are highlighted and scientific studies of other foods with known effects on the gastrointestinal tract are consulted to find likely mechanisms of action. While the effects of kiwifruit fiber are well documented, observed increases in gastrointestinal motility caused by kiwifruit are not fully characterized. There are a number of identified mechanisms that may be activated by kiwifruit compounds, such as the induction of motility via protease-activated signaling, modulation of microflora, changes in colonic methane status, bile flux, or mediation of inflammatory processes.
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Affiliation(s)
- Simone Birgit Bayer
- a Department of Pathology , Center for Free Radical Research, University of Otago , 2 Riccarton Avenue, PO Box 4345, Christchurch , New Zealand
| | - Richard Blair Gearry
- b Department of Medicine , University of Otago , 2 Riccarton Avenue, PO Box 4345, Christchurch , New Zealand
| | - Lynley Ngaio Drummond
- c Drummond Food Science Advisory Ltd. , 1137 Drain Road, Killinchy RD 2, Leeston , New Zealand
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19
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Kempuraj D, Thangavel R, Selvakumar GP, Zaheer S, Ahmed ME, Raikwar SP, Zahoor H, Saeed D, Natteru PA, Iyer S, Zaheer A. Brain and Peripheral Atypical Inflammatory Mediators Potentiate Neuroinflammation and Neurodegeneration. Front Cell Neurosci 2017; 11:216. [PMID: 28790893 PMCID: PMC5522882 DOI: 10.3389/fncel.2017.00216] [Citation(s) in RCA: 234] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 07/05/2017] [Indexed: 12/18/2022] Open
Abstract
Neuroinflammatory response is primarily a protective mechanism in the brain. However, excessive and chronic inflammatory responses can lead to deleterious effects involving immune cells, brain cells and signaling molecules. Neuroinflammation induces and accelerates pathogenesis of Parkinson’s disease (PD), Alzheimer’s disease (AD) and Multiple sclerosis (MS). Neuroinflammatory pathways are indicated as novel therapeutic targets for these diseases. Mast cells are immune cells of hematopoietic origin that regulate inflammation and upon activation release many proinflammatory mediators in systemic and central nervous system (CNS) inflammatory conditions. In addition, inflammatory mediators released from activated glial cells induce neurodegeneration in the brain. Systemic inflammation-derived proinflammatory cytokines/chemokines and other factors cause a breach in the blood brain-barrier (BBB) thereby allowing for the entry of immune/inflammatory cells including mast cell progenitors, mast cells and proinflammatory cytokines and chemokines into the brain. These peripheral-derived factors and intrinsically generated cytokines/chemokines, α-synuclein, corticotropin-releasing hormone (CRH), substance P (SP), beta amyloid 1–42 (Aβ1–42) peptide and amyloid precursor proteins can activate glial cells, T-cells and mast cells in the brain can induce additional release of inflammatory and neurotoxic molecules contributing to chronic neuroinflammation and neuronal death. The glia maturation factor (GMF), a proinflammatory protein discovered in our laboratory released from glia, activates mast cells to release inflammatory cytokines and chemokines. Chronic increase in the proinflammatory mediators induces neurotoxic Aβ and plaque formation in AD brains and neurodegeneration in PD brains. Glial cells, mast cells and T-cells can reactivate each other in neuroinflammatory conditions in the brain and augment neuroinflammation. Further, inflammatory mediators from the brain can also enter into the peripheral system through defective BBB, recruit immune cells into the brain, and exacerbate neuroinflammation. We suggest that mast cell-associated inflammatory mediators from systemic inflammation and brain could augment neuroinflammation and neurodegeneration in the brain. This review article addresses the role of some atypical inflammatory mediators that are associated with mast cell inflammation and their activation of glial cells to induce neurodegeneration.
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Affiliation(s)
- Duraisamy Kempuraj
- Harry S. Truman Memorial Veteran's Hospital, U.S. Department of Veterans AffairsColumbia, MO, United States.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Ramasamy Thangavel
- Harry S. Truman Memorial Veteran's Hospital, U.S. Department of Veterans AffairsColumbia, MO, United States.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Govindhasamy P Selvakumar
- Harry S. Truman Memorial Veteran's Hospital, U.S. Department of Veterans AffairsColumbia, MO, United States.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Smita Zaheer
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Mohammad E Ahmed
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Sudhanshu P Raikwar
- Harry S. Truman Memorial Veteran's Hospital, U.S. Department of Veterans AffairsColumbia, MO, United States.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Haris Zahoor
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Daniyal Saeed
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Prashant A Natteru
- Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Shankar Iyer
- Harry S. Truman Memorial Veteran's Hospital, U.S. Department of Veterans AffairsColumbia, MO, United States.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
| | - Asgar Zaheer
- Harry S. Truman Memorial Veteran's Hospital, U.S. Department of Veterans AffairsColumbia, MO, United States.,Department of Neurology and the Center for Translational Neuroscience, School of Medicine, University of MissouriColumbia, MO, United States
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20
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Abstract
BACKGROUND Vorapaxar, a novel antiplatelet thrombin PAR-1 inhibitor, is currently approved for post myocardial infarction and peripheral artery disease indications with concomitant use of clopidogrel and/or aspirin. The vorapaxar safety profile was acceptable. However, aside from heightened bleeding risks, excesses of solid cancers and diplopia, there were more amyotrophic lateral sclerosis (ALS) diagnoses after vorapaxar. STUDY QUESTION To assess the Food and Drug Administration (FDA) reviews on the potential association of vorapaxar with ALS. STUDY DESIGN The review the public FDA records on reported adverse events after vorapaxar. MEASURES AND OUTCOMES Incidence of ALS after vorapaxar and placebo. RESULTS The ALS risk appears very small, about 1 case per 10,000 treated subjects, but quite probable. Indeed, there were overall 2 placebo and 4 vorapaxar ALS incidences in the Phase III clinical trials. CONCLUSIONS Potential adverse association of vorapaxar with ALS risks may be related to off-target neuronal PAR receptor(s) blockade beyond platelet inhibition.
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21
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Tan Z, Feagin TA, Heemstra JM. Temporal Control of Aptamer Biosensors Using Covalent Self-Caging To Shift Equilibrium. J Am Chem Soc 2016; 138:6328-31. [PMID: 27159220 DOI: 10.1021/jacs.6b00934] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Aptamer-based sensors provide a versatile and effective platform for the detection of chemical and biological targets. These sensors have been optimized to function in multiple formats, however, a remaining limitation is the inability to achieve temporal control over their sensing function. To overcome this challenge, we took inspiration from nature's ability to temporally control the activity of enzymes and protein receptors through covalent self-caging. We applied this strategy to structure-switching aptamer sensors through the installation of a cleavable linker between the two DNA fragments that comprise the sensor. Analogous to self-caged proteins, installation of this linker shifts the equilibrium of the aptamer sensor to disfavor target binding. However, activity can be restored in a time-resolved manner by cleavage of the linker. To demonstrate this principle, we chose a photocleavable linker and found that installation of the linker eliminates target binding, even at high target concentrations. However, upon irradiation with 365 nm light, sensor activity is restored with response kinetics that mirror those of the linker cleavage reaction. A key benefit of our approach is generality, which is demonstrated by grafting the photocleavable linker onto a different aptamer sensor and showing that an analogous level of temporal control can be achieved for sensing of the new target molecule. These results demonstrate that nature's self-caging approach can be effectively applied to non-natural receptors to provide precise temporal control over function. We envision that this will be of especially high utility for deploying aptamer sensors in biological environments.
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Affiliation(s)
- Zhesen Tan
- Department of Chemistry and the Center for Cell and Genome Science, University of Utah , Salt Lake City, Utah 84112, United States
| | - Trevor A Feagin
- Department of Chemistry and the Center for Cell and Genome Science, University of Utah , Salt Lake City, Utah 84112, United States
| | - Jennifer M Heemstra
- Department of Chemistry and the Center for Cell and Genome Science, University of Utah , Salt Lake City, Utah 84112, United States
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22
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Concentration-Dependent Dual Role of Thrombin in Protection of Cultured Rat Cortical Neurons. Neurochem Res 2015; 40:2220-9. [PMID: 26342829 DOI: 10.1007/s11064-015-1711-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 08/02/2015] [Accepted: 08/25/2015] [Indexed: 10/23/2022]
Abstract
Thrombin's role in the nervous system is not well understood. Under conditions of blood-brain barrier compromise (e.g., neurosurgery or stroke), thrombin can result in neuroapoptosis and the formation of glial scars. Despite this, preconditioning with thrombin has been found to be neuroprotective in models of cerebral ischemia and intracerebral hemorrhage. We investigated the effects of physiologically relevant concentrations of thrombin on cortical neurons using two culture-based assays. We examined thrombin's effect on neurites by quantitative analysis of fluorescently labeled neurons. To characterize thrombin's effects on neuron survival, we spectrophotometrically measured changes in enzymatic activity. Using receptor agonists and thrombin inhibitors, we separately examined the role of thrombin and its receptor in neuroprotection. We found that low concentrations of thrombin (1 nM) enhances neurite growth and branching, neuron viability, and protects against excitotoxic damage. In contrast, higher concentrations of thrombin (100 nM) are potentially detrimental to neuronal health as evidenced by inhibition of neurite growth. Lower concentrations of thrombin resulted in equivalent neuroprotection as the antifibrinolytic, aprotinin, and the direct thrombin inhibitor, argatroban. Interestingly, exogenous application of the species-specific thrombin inhibitor, antithrombin III, was detrimental to neuronal health; suggesting that some endogenous thrombin is necessary for optimal neuron health in our culture system. Activation of the thrombin receptor, protease-activated receptor-1 (PAR-1), via micromolar concentrations of the thrombin receptor agonist peptide, TRAP, did not adversely affect neuronal viability. An optimal concentration of thrombin exists to enhance neuronal health. Neurotoxic effects of thrombin do not involve activation of PAR receptors and thus separate pharmacologic manipulation of thrombin's receptor in the setting of direct thrombin inhibitors could be a potential neuroprotective strategy.
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Kempuraj D, Thangavel R, Yang E, Pattani S, Zaheer S, Santillan DA, Santillan MK, Zaheer A. Dopaminergic Toxin 1-Methyl-4-Phenylpyridinium, Proteins α-Synuclein and Glia Maturation Factor Activate Mast Cells and Release Inflammatory Mediators. PLoS One 2015; 10:e0135776. [PMID: 26275153 PMCID: PMC4537263 DOI: 10.1371/journal.pone.0135776] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 07/24/2015] [Indexed: 12/23/2022] Open
Abstract
Parkinson’s disease (PD) is characterized by the presence of Lewy bodies and degeneration of dopaminergic neurons. 1-methyl-4-phenylpyridinium (MPP+), a metabolite of neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and Lewy body component α-synuclein activates glia in PD pathogenesis. Mast cells and glia maturation factor (GMF) are implicated in neuroinflammatory conditions including Multiple Sclerosis. However, the role of mast cells in PD is not yet known. We have analyzed the effect of recombinant GMF, MPP+, α-synuclein and interleukin-33 (IL-33) on mouse bone marrow-derived cultured mast cells (BMMCs), human umbilical cord blood-derived cultured mast cells (hCBMCs) and mouse brain-derived cultured astrocytes by quantifying cytokines/chemokines released using ELISA or by detecting the expression of co-stimulatory molecules CD40 and CD40L by flow cytometry. GMF significantly released chemokine (C-C motif) ligand 2 (CCL2) from BMMCs but its release was reduced in BMMCs from GMF knockout mice. GMF, α-synuclein and MPP+ released IL-1β, β-hexosaminidase from BMMCs, and IL-8 from hCBMCs. GMF released CCL5, and IL-33- induced the expression of GMF from hCBMCs. Novel GMF expression was detected in hCBMCs and BMMCs by immunocytochemistry. GMF released tumor necrosis factor-alpha (TNF-α) from mouse astrocytes, and this release was greater in BMMC- astrocyte coculture than in individual cultures. Flow cytometry results showed increased IL-33 expression by GMF and MPP+, and GMF-induced CD40 expression in astrocytes. Proinflammatory mediator release by GMF, MPP+ and α-synuclein, as well as GMF expression by mast cells indicate a potential therapeutic target for neurodegenerative diseases including PD.
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Affiliation(s)
- Duraisamy Kempuraj
- Veterans Affairs Health Care System, Iowa City, Iowa, United States of America
- Department of Neurology, Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States of America
| | - Ramasamy Thangavel
- Veterans Affairs Health Care System, Iowa City, Iowa, United States of America
- Department of Neurology, Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States of America
| | - Evert Yang
- Department of Neurology, Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States of America
| | - Sagar Pattani
- Department of Neurology, Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States of America
| | - Smita Zaheer
- Department of Neurology, Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States of America
| | - Donna A. Santillan
- Department of Obstetrics and Gynecology, Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States of America
| | - Mark K. Santillan
- Department of Obstetrics and Gynecology, Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States of America
| | - Asgar Zaheer
- Veterans Affairs Health Care System, Iowa City, Iowa, United States of America
- Department of Neurology, Carver College of Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa, United States of America
- * E-mail:
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24
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Joyal JS, Nim S, Zhu T, Sitaras N, Rivera JC, Shao Z, Sapieha P, Hamel D, Sanchez M, Zaniolo K, St-Louis M, Ouellette J, Montoya-Zavala M, Zabeida A, Picard E, Hardy P, Bhosle V, Varma DR, Gobeil F, Beauséjour C, Boileau C, Klein W, Hollenberg M, Ribeiro-da-Silva A, Andelfinger G, Chemtob S. Subcellular localization of coagulation factor II receptor-like 1 in neurons governs angiogenesis. Nat Med 2014; 20:1165-73. [PMID: 25216639 DOI: 10.1038/nm.3669] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 07/23/2014] [Indexed: 02/07/2023]
Abstract
Neurons have an important role in retinal vascular development. Here we show that the G protein-coupled receptor (GPCR) coagulation factor II receptor-like 1 (F2rl1, previously known as Par2) is abundant in retinal ganglion cells and is associated with new blood vessel formation during retinal development and in ischemic retinopathy. After stimulation, F2rl1 in retinal ganglion cells translocates from the plasma membrane to the cell nucleus using a microtubule-dependent shuttle that requires sorting nexin 11 (Snx11). At the nucleus, F2rl1 facilitates recruitment of the transcription factor Sp1 to trigger Vegfa expression and, in turn, neovascularization. In contrast, classical plasma membrane activation of F2rl1 leads to the expression of distinct genes, including Ang1, that are involved in vessel maturation. Mutant versions of F2rl1 that prevent nuclear relocalization but not plasma membrane activation interfere with Vegfa but not Ang1 expression. Complementary angiogenic factors are therefore regulated by the subcellular localization of a receptor (F2rl1) that governs angiogenesis. These findings may have implications for the selectivity of drug actions based on the subcellular distribution of their targets.
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Affiliation(s)
- Jean-Sébastien Joyal
- 1] Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada. [2] Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada. [3] Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada. [4] Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada. [5]
| | - Satra Nim
- 1] Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada. [2]
| | - Tang Zhu
- 1] Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada. [2]
| | - Nicholas Sitaras
- 1] Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada. [2] Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada
| | - José Carlos Rivera
- 1] Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada. [2] Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada
| | - Zhuo Shao
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Przemyslaw Sapieha
- Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada
| | - David Hamel
- Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada
| | - Melanie Sanchez
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Karine Zaniolo
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Manon St-Louis
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Johanne Ouellette
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | | | - Alexandra Zabeida
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Emilie Picard
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Pierre Hardy
- Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Vikrant Bhosle
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Daya R Varma
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Fernand Gobeil
- Department of Pharmacology, Sherbrooke University, Sherbrooke, Quebec, Canada
| | | | - Christelle Boileau
- Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada
| | - William Klein
- Department of Systems Biology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Morley Hollenberg
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | | | - Gregor Andelfinger
- Department of Cardiology, CHU Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada
| | - Sylvain Chemtob
- 1] Department of Pediatrics, Centre Hospitalier Universitaire (CHU) Sainte-Justine Research Center, Université de Montréal, Montréal, Québec, Canada. [2] Department of Ophthalmology, Hôpital Maisonneuve-Rosemont Research Center, Université de Montreal, Montreal, Québec, Canada. [3] Department of Pharmacology, Université de Montréal, Montréal, Québec, Canada. [4] Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
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25
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Mayer EA, Savidge T, Shulman RJ. Brain-gut microbiome interactions and functional bowel disorders. Gastroenterology 2014; 146:1500-12. [PMID: 24583088 PMCID: PMC4114504 DOI: 10.1053/j.gastro.2014.02.037] [Citation(s) in RCA: 294] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 01/02/2014] [Accepted: 02/25/2014] [Indexed: 12/02/2022]
Abstract
Alterations in the bidirectional interactions between the intestine and the nervous system have important roles in the pathogenesis of irritable bowel syndrome (IBS). A body of largely preclinical evidence suggests that the gut microbiota can modulate these interactions. A small and poorly defined role for dysbiosis in the development of IBS symptoms has been established through characterization of altered intestinal microbiota in IBS patients and reported improvement of subjective symptoms after its manipulation with prebiotics, probiotics, or antibiotics. It remains to be determined whether IBS symptoms are caused by alterations in brain signaling from the intestine to the microbiota or primary disruption of the microbiota, and whether they are involved in altered interactions between the brain and intestine during development. We review the potential mechanisms involved in the pathogenesis of IBS in different groups of patients. Studies are needed to better characterize alterations to the intestinal microbiome in large cohorts of well-phenotyped patients, and to correlate intestinal metabolites with specific abnormalities in gut-brain interactions.
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Affiliation(s)
- Emeran A Mayer
- Oppenheimer Center for Neurobiology of Stress, Division of Digestive Diseases, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California.
| | - Tor Savidge
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas; Texas Children's Microbiome Center, Department of Pathology, Houston, Texas; Texas Children's Hospital, Houston, Texas
| | - Robert J Shulman
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas; Children's Nutrition Research Center, Houston, Texas; Texas Children's Hospital, Houston, Texas
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Yan J, Manaenko A, Chen S, Klebe D, Ma Q, Caner B, Fujii M, Zhou C, Zhang JH. Role of SCH79797 in maintaining vascular integrity in rat model of subarachnoid hemorrhage. Stroke 2013; 44:1410-7. [PMID: 23539525 DOI: 10.1161/strokeaha.113.678474] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND PURPOSE Plasma thrombin concentration is increased after subarachnoid hemorrhage (SAH). However, the role of thrombin receptor (protease-activated receptor-1 [PAR-1]) in endothelial barrier disruption has not been studied. The aims of this study were to investigate the role of PAR-1 in orchestrating vascular permeability and to assess the potential therapeutics of a PAR-1 antagonist, SCH79797, through maintaining vascular integrity. METHODS SCH79797 was injected intraperitoneally into male Sprauge-Dawley rats undergoing SAH by endovascular perforation. Assessment was conducted at 24 hours after SAH for brain water content, Evans blue content, and neurobehavioral testing. To explore the role of PAR-1 activation and the specific mechanism of SCH79797's effect after SAH, Western blot, immunoprecipitation, and immunofluorescence of hippocampus tissue were performed. A p21-activated kinase-1 (PAK1) inhibitor, IPA-3, was used to explore the underlying protective mechanism of SCH79797. RESULTS At 24 hours after SAH, animals treated with SCH79797 demonstrated a reduction in brain water content, Evans blue content, and neurobehavioral deficits. SCH79797 also attenuated PAR-1 expression and maintained the level of vascular endothelial-cadherin, an important component of adherens junctions. Downstream to PAR-1, c-Src-dependent activation of p21-activated kinase-1 led to an increased serine/threonine phosphorylation of vascular endothelial-cadherin; immunoprecipitation results revealed an enhanced binding of phosphorylated vascular endothelial-cadherin with endocytosis orchestrator β-arrestin-2. These pathological states were suppressed after SCH79797 treatment. CONCLUSIONS PAR-1 activation after SAH increases microvascular permeability, at least, partly through a PAR-1-c-Src-p21-activated kinase-1-vascular endothelial-cadherin phosphorylation pathway. Through suppressing PAR-1 activity, SCH79797 plays a protective role in maintaining microvascular integrity after SAH.
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Affiliation(s)
- Junhao Yan
- Department of Anatomy and Histology, School of Basic Medical Sciences, Peking University, Beijing, China
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27
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Ibeakanma C, Ochoa-Cortes F, Miranda-Morales M, McDonald T, Spreadbury I, Cenac N, Cattaruzza F, Hurlbut D, Vanner S, Bunnett N, Vergnolle N, Vanner S. Brain-gut interactions increase peripheral nociceptive signaling in mice with postinfectious irritable bowel syndrome. Gastroenterology 2011; 141:2098-2108.e5. [PMID: 21856270 DOI: 10.1053/j.gastro.2011.08.006] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 07/14/2011] [Accepted: 08/09/2011] [Indexed: 01/14/2023]
Abstract
BACKGROUND & AIMS To investigate the peripheral sensory effects of repeated stress in patients with postinfectious irritable bowel syndrome (IBS), we tested whether stress following self-limiting bacterial colitis increases colonic dorsal root ganglia (DRG) nociceptive signaling. METHODS C57BL/6 mice were infected with Citrobacter rodentium. Stress was induced using a 9-day water avoidance paradigm (days 21-30 after infection). Colonic DRG neuronal excitability was measured using perforated patch clamp techniques, in vitro multi-unit afferent recordings, and measurements of visceromotor reflexes. RESULTS Combined stress and prior infection increased corticosterone and epinephrine levels, compared with infected animals, but did not alter the resolution of colonic inflammation. These changes were associated with increased neuronal excitability and parallel changes in multi-unit afferent recordings and visceromotor reflex thresholds. Protease activity was increased at day 30 following infection with C rodentium. Protease inhibitors markedly reduced the effects of colonic supernatants on neuronal excitability from C rodentium but not stressed animals. Colonic DRG neurons expressed messenger RNAs for the β(2) adrenergic and glucocorticoid receptors; incubation with stress mediators recapitulated the effects on neuronal excitability observed with chronic stress alone. PAR2 activation with concentrations of the activating peptide SLIGRL that had no effect on neuronal excitability in controls caused marked increases in excitability when applied to neurons from chronically stressed animals. CONCLUSIONS Stress, combined with prior acute colitis, results in exaggerated peripheral nociceptive signaling. Proteases and stress mediators can signal directly to colonic DRG neurons; further analysis of these pathways could provide new targets for treatment of patients with postinfectious IBS.
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Affiliation(s)
- Charles Ibeakanma
- Gastrointestinal Diseases Research Unit, Kingston General Hospital, Queen's University, Kingston, Ontario, Canada
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28
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Zündorf G, Reiser G. The phosphorylation status of extracellular-regulated kinase 1/2 in astrocytes and neurons from rat hippocampus determines the thrombin-induced calcium release and ROS generation. J Neurochem 2011; 119:1194-204. [PMID: 21988180 DOI: 10.1111/j.1471-4159.2011.07527.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Challenge of protease-activated receptors induces cytosolic Ca(2+) concentration ([Ca(2+) ](c)) increase, mitogen-activated protein kinase activation and reactive oxygen species (ROS) formation with a bandwidth of responses in individual cells. We detected in this study in situ the thrombin-induced [Ca(2+) ](c) rise and ROS formation in dissociated hippocampal astrocytes and neurons in a mixed culture. In identified cells, single cell responses were correlated with extracellular-regulated kinase (ERK)1/2 phosphorylation level. On average, in astrocytes, thrombin induced a transient [Ca(2+) ](c) rise with concentration-dependent increase in amplitude and extrusion rate and high ERK1/2 phosphorylation level. Correlation analysis of [Ca(2+) ](c) response characteristics of single astrocytes reveals that astrocytes with nuclear phosphoERK1/2 localization have a smaller Ca(2+) amplitude and extrusion rate compared with cells with a cytosolic phosphoERK1/2 localization. In naive neurons, without thrombin challenge, variable ERK1/2 phosphorylation patterns are observed. ROS were detected by hydroethidine. Only in neurons with increased ERK1/2 phosphorylation level, we see sustained intracellular rise in fluorescence of the dye lasting over several minutes. ROS formation was abolished by pre-incubation with the NADPH oxidase inhibitor apocynin. Additionally, thrombin induced an immediate, transient hydroethidine fluorescence increase. This was interpreted as NADPH oxidase-mediated O(2) (•-) -release into the extracellular milieu, because it was decreased by pre-incubation with apocynin, and could be eluted by superfusion. In conclusion, the phosphorylation status of ERK1/2 determines the thrombin-dependent [Ca(2+) ](c) increase and ROS formation and, thus, influences the capacity of thrombin to regulate neuroprotection or neurodegeneration.
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Affiliation(s)
- Gregor Zündorf
- Institut für Neurobiochemie, Medizinische Fakultät, Otto-von-Guericke-Universität Magdeburg, Magdeburg, Germany
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29
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Boerma M, Hauer-Jensen M. Potential targets for intervention in radiation-induced heart disease. Curr Drug Targets 2011; 11:1405-12. [PMID: 20583977 DOI: 10.2174/1389450111009011405] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2010] [Accepted: 04/05/2010] [Indexed: 12/14/2022]
Abstract
Radiotherapy of thoracic and chest wall tumors, if all or part of the heart was included in the radiation field, can lead to radiation-induced heart disease (RIHD), a late and potentially severe side effect. RIHD presents clinically several years after irradiation and manifestations include accelerated atherosclerosis, pericardial and myocardial fibrosis, conduction abnormalities, and injury to cardiac valves. The pathogenesis of RIHD is largely unknown, and a treatment is not available. Hence, ongoing pre-clinical studies aim to elucidate molecular and cellular mechanisms of RIHD. Here, an overview of recent pre-clinical studies is given, and based on the results of these studies, potential targets for intervention in RIHD are discussed.
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Affiliation(s)
- M Boerma
- Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.
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Boerma M, Hauer-Jensen M. Preclinical research into basic mechanisms of radiation-induced heart disease. Cardiol Res Pract 2010; 2011:858262. [PMID: 20953374 PMCID: PMC2952915 DOI: 10.4061/2011/858262] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Accepted: 09/04/2010] [Indexed: 01/20/2023] Open
Abstract
Radiation-induced heart disease (RIHD) is a potentially severe side effect of radiotherapy of thoracic and chest wall tumors if all or part of the heart was included in the radiation field. RIHD presents clinically several years after irradiation and manifestations include accelerated atherosclerosis, pericardial and myocardial fibrosis, conduction abnormalities, and injury to cardiac valves. There is no method to prevent or reverse these injuries when the heart is exposed to ionizing radiation. This paper presents an overview of recent studies that address the role of microvascular injury, endothelial dysfunction, mast cells, and the renin angiotensin system in animal models of cardiac radiation injury. These insights into the basic mechanisms of RIHD may lead to the identification of targets for intervention in this late radiotherapy side effect.
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Affiliation(s)
- M. Boerma
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, 4301 West Markham, Slot 522-10, Little Rock, AR 72205, USA
| | - M. Hauer-Jensen
- Division of Radiation Health, Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, 4301 West Markham, Slot 522-10, Little Rock, AR 72205, USA
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Abstract
Protease-activated receptors (PARs) are members of a subfamily of G-protein-coupled receptors that regulate diverse cell functions in response to proteolytic cleavage of an anchored peptide domain that acts as a 'tethered' receptor-activating ligand. PAR-1 and PAR-2 in particular are present throughout the gastrointestinal (GI) tract and play prominent roles in the regulation of GI epithelial function, motility, inflammation and nociception. In a recent article in Neurogastroenterology and Motility, Wang et al. demonstrate, for the first time, that PAR-1 and PAR-2 are present on preganglionic parasympathetic neurons within the rat brainstem. As in other cellular systems, proteases such as thrombin and trypsin activate PAR-1 and PAR-2 on neurons of the dorsal motor nucleus of the vagus (DMV), leading to an increase in intracellular calcium levels via signal transduction mechanisms involving activation of phospholipase C and inositol triphosphate (IP3). The authors also report that the level of PAR-1 and PAR-2 transcripts in DMV tissue is increased following experimental colitis, suggesting that inflammatory conditions may modulate neuronal behavior or induce plasticity within central vagal neurocircuits. It seems reasonable to hypothesize, therefore, that the activity and behavior of vagal efferent motoneurons may be modulated directly by local and/or systemic proteases released during inflammation. This, in turn, may contribute to the increased incidence of functional GI disorders, including gastric dysmotility, delayed emptying and gastritis observed in patients with inflammatory bowel diseases.
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Affiliation(s)
- K N Browning
- Department of Neural and Behavioral Sciences, Penn State College of Medicine, Hershey, PA 17033-0850, USA.
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33
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Characterization of endogenous calcium responses in neuronal cell lines. Biochem Pharmacol 2009; 79:908-20. [PMID: 19883631 DOI: 10.1016/j.bcp.2009.10.020] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 10/20/2009] [Accepted: 10/21/2009] [Indexed: 11/23/2022]
Abstract
An increasing number of putative therapeutic targets have been identified in recent years for the treatment of neuronal pathophysiologies including pain, epilepsy, stroke and schizophrenia. Many of these targets signal through calcium (Ca(2+)), either by directly facilitating Ca(2+) influx through an ion channel, or through activation of G proteins that couple to intracellular Ca(2+) stores or voltage-gated Ca(2+) channels. Immortalized neuronal cell lines are widely used models to study neuropharmacology. However, systematic pharmacological characterization of the receptors and ion channels expressed in these cell lines is lacking. In this study, we systematically assessed endogenous Ca(2+) signaling in response to addition of agonists at potential therapeutic targets in a range of cell lines of neuronal origin (ND7/23, SH-SY5Y, 50B11, F11 and Neuro2A cells) as well as HEK293 cells, a cell line commonly used for over-expression of receptors and ion channels. This study revealed a remarkable diversity of endogenous Ca(2+) responses in these cell lines, with one or more cell lines responding to addition of trypsin, bradykinin, ATP, nicotine, acetylcholine, histamine and neurotensin. Subtype specificity of these responses was inferred from agonist potency and the effect of receptor subtype specific antagonist. Surprisingly, HEK293 and SH-SY5Y cells responded to the largest number of agonists with potential roles in neuronal signaling. These findings have implications for the heterologous expression of neuronal receptors and ion channels in these cell lines, and highlight the potential of neuron-derived cell lines for the study of a range of endogenously expressed receptors and ion channels that signal through Ca(2+).
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Proteolysis of prion protein by cathepsin S generates a soluble β-structured intermediate oligomeric form, with potential implications for neurotoxic mechanisms. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2008; 38:209-18. [DOI: 10.1007/s00249-008-0371-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 09/09/2008] [Accepted: 09/10/2008] [Indexed: 10/21/2022]
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35
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Effect of PAR1 agonist on acetylcholine secretion in a newly formed neuromuscular synapse in mice. Bull Exp Biol Med 2008; 144:653-6. [PMID: 18683487 DOI: 10.1007/s10517-007-0396-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Peptide agonist of PARI in a concentration of 10 microM significantly facilitated neuromuscular transmission in newly formed synapses in mice. The absence of changes in the amplitude of miniature end-plate potentials attests to presynaptic mechanism of the effect of PAR1 agonist. The effect of the peptide was blocked by protein kinase A inhibitor H89 (1 microM). Blockade of inositol-1,4,5-trisphosphate receptors with 2-amino-ethoxydiphenylborate (30 microM) did not prevent the effects of PARI agonist. Inhibition of protein kinase C with bisindolylmaleimide (1 microM) facilitated neuromuscular transmission in newly formed synapses. Protein kinase C inhibition was associated with reversal of the object of PARI agonist: transmission inhibition instead of facilitation.
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Misaki T, Satoh YI, Saino T, Kuroda T, Masu K, Russa DA, Ogawa A. Immunohistochemical localization of protease-activated receptors in cerebral and testicular arterioles of rats: their dependence on arteriole size and organ-specificity. ACTA ACUST UNITED AC 2008; 71:179-84. [DOI: 10.1679/aohc.71.179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Toshinari Misaki
- Departments of Anatomy (Cell Biology Division), Iwate Medical University
- Departments of Neurosurgery, Iwate Medical University
| | - Yoh-ichi Satoh
- Departments of Anatomy (Cell Biology Division), Iwate Medical University
| | - Tomoyuki Saino
- Departments of Anatomy (Cell Biology Division), Iwate Medical University
| | - Takashi Kuroda
- Departments of Anatomy (Cell Biology Division), Iwate Medical University
| | - Kazuki Masu
- Departments of Anatomy (Cell Biology Division), Iwate Medical University
- Departments of Neurosurgery, Iwate Medical University
| | - D. A. Russa
- Departments of Anatomy (Cell Biology Division), Iwate Medical University
| | - Akira Ogawa
- Departments of Neurosurgery, Iwate Medical University
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37
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Rijnierse A, Nijkamp FP, Kraneveld AD. Mast cells and nerves tickle in the tummy: implications for inflammatory bowel disease and irritable bowel syndrome. Pharmacol Ther 2007; 116:207-35. [PMID: 17719089 DOI: 10.1016/j.pharmthera.2007.06.008] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Accepted: 06/20/2007] [Indexed: 12/12/2022]
Abstract
Mast cells are well known as versatile cells capable of releasing and producing a variety of inflammatory mediators upon activation and are often found in close proximity of neurons. In addition, inflammation leads to local activation of neurons resulting in the release neuropeptides, which also play an important immune modulatory role by stimulation of immune cells. In intestinal disorders like inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), the number of mast cells is known to be much higher than in the normal intestine. Moreover, both these disorders are also reported to be associated with alterations in neuropeptide content and in neural innervation. Mutual association between mast cells and enteric nerves has been demonstrated to be increased in pathophysiological conditions and contribute to spreading and amplification of the response in IBD and IBS. In this review the focus lies on studies appointed to the direct interaction between mast cells and nerves in IBD, IBS, and animal models for these disorders so far.
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Affiliation(s)
- Anneke Rijnierse
- Department of Pharmacology and Pathophysiology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands.
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Kayssi A, Amadesi S, Bautista F, Bunnett NW, Vanner S. Mechanisms of protease-activated receptor 2-evoked hyperexcitability of nociceptive neurons innervating the mouse colon. J Physiol 2007; 580:977-91. [PMID: 17289784 PMCID: PMC2075455 DOI: 10.1113/jphysiol.2006.126599] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Agonists of protease-activated receptor 2 (PAR(2)) evoke hyperexcitability of dorsal root ganglia (DRG) neurons by unknown mechanisms. We examined the cellular mechanisms underlying PAR(2)-evoked hyperexcitability of mouse colonic DRG neurons to determine their potential role in pain syndromes such as visceral hyperalgesia. Colonic DRG neurons were identified by injecting Fast Blue and DiI retrograde tracers into the mouse colon. Using immunofluorescence, we found that DiI-labelled neurons contained PAR(2) immunoreactivity, confirming the presence of receptors on colonic neurons. Whole-cell current-clamp recordings of acutely dissociated neurons demonstrated that PAR(2) activation with a brief application (3 min) of PAR(2) agonists, SLIGRL-NH(2) and trypsin, evoked sustained depolarizations (up to 60 min) which were associated with increased input resistance and a marked reduction in rheobase (50% at 30 min). In voltage clamp, SLIGRL-NH(2) markedly suppressed delayed rectifier I(K) currents (55% at 10 min), but had no effect on the transient I(A) current or TTX-resistant Na(+) currents. In whole-cell current-clamp recordings, the sustained excitability evoked by PAR(2) activation was blocked by the PKC inhibitor, calphostin, and the ERK(1/2) inhibitor PD98059. Studies of ERK(1/2) phosphorylation using confocal microscopy demonstrated that SLIGRL-NH(2) increased levels of immunoreactive pERK(1/2) in DRG neurons, particularly in proximity to the plasma membrane. Thus, activation of PAR(2) receptors on colonic nociceptive neurons causes sustained hyperexcitability that is related, at least in part, to suppression of delayed rectifier I(K) currents. Both PKC and ERK(1/2) mediate the PAR(2)-induced hyperexcitability. These studies describe a novel mechanism of sensitization of colonic nociceptive neurons that may be implicated in conditions of visceral hyperalgesia such as irritable bowel syndrome.
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Affiliation(s)
- Ahmed Kayssi
- Gastrointestinal Diseases Research Unit, Queen's University, Kingston, Ontario, Canada
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