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Wang S, Zou Z, Tang Z, Deng J. AMPK/MTOR/TP53 Signaling Pathway Regulation by Calcitonin Gene-Related Peptide Reduces Oxygen-Induced Lung Damage in Neonatal Rats through Autophagy Promotion. Inflammation 2024; 47:1083-1108. [PMID: 38502251 DOI: 10.1007/s10753-023-01963-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 12/10/2023] [Accepted: 12/27/2023] [Indexed: 03/21/2024]
Abstract
Our previous studies indicated that calcitonin gene-related peptide (CGRP) alleviates hyperoxia-induced lung injury and suggested the possible involvement of autophagy in this process. Herein, we aimed to further explore the potential involvement of tumor protein p53 (TP53) and autophagy in the mode of action of CGRP against hyperoxia-induced lung injury in vitro and in vivo. The study conducted tests on type II alveolar epithelial cells (AECII) and rats that were subjected to hyperoxia treatment or combined treatment of hyperoxia with CGRP, CGRP inhibitor, rapamycin (an autophagy agonist), 3-methyladenine (3-MA, an autophagy inhibitor), TP53 silencing/inhibitor (pifithrin-α), or expression vector/activator (PRIMA-1 (2,2-bis(hydroxymethyl)-3-quinuclidinone)) and their corresponding controls. We found that oxidative stress, apoptosis, and autophagy were all increased by hyperoxia treatment in vitro. However, treating AECII cells with CGRP reversed hyperoxia-induced oxidative stress and apoptosis but further promoted autophagy. In addition, the combined treatment with rapamycin or TP53 silencing with CGRP promoted the effect of CGRP, while contrary results were obtained with combined therapy with 3-MA or TP53 overexpression. In vivo, the number of hyperoxia-induced autophagosomes was promoted in the lung tissue of neonatal rats. Furthermore, hyperoxia increased the expression levels of AMP-activated protein kinase (AMPK) alpha 1 (also known as protein kinase AMP-activated catalytic subunit alpha 1 (PRKAA1)) but inhibited TP53 and mechanistic target of rapamycin (MTOR); these expression trends were regulated by CGRP treatment. In conclusion, we showed that CGRP can attenuate hyperoxia-induced lung injury in neonatal rats by enhancing autophagy and regulating the TP53/AMPK/MTOR crosstalk axis.
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Affiliation(s)
- Shaohua Wang
- Neonatal Intensive Care Unit, Women and Children Health Institute of Futian, Jintian South Road No. 2002, Futian District, Shenzhen, 518045, China.
| | - Zhengzhuang Zou
- Neonatal Intensive Care Unit, Women and Children Health Institute of Futian, Jintian South Road No. 2002, Futian District, Shenzhen, 518045, China
| | - Zanmei Tang
- Neonatal Intensive Care Unit, Women and Children Health Institute of Futian, Jintian South Road No. 2002, Futian District, Shenzhen, 518045, China
| | - Jian Deng
- Neonatal Intensive Care Unit, Women and Children Health Institute of Futian, Jintian South Road No. 2002, Futian District, Shenzhen, 518045, China
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Holmes D, Corr M, Thomas G, Harbinson M, Campbell M, Spiers P, Bell D. Protective effects of intermedin/adrenomedullin-2 in a cellular model of human pulmonary arterial hypertension. Peptides 2020; 126:170267. [PMID: 32017948 DOI: 10.1016/j.peptides.2020.170267] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 01/30/2020] [Accepted: 01/31/2020] [Indexed: 11/18/2022]
Abstract
Proliferation of pulmonary fibroblasts (PF) and distal migration of smooth muscle cells (PSM) are hallmarks of pulmonary arterial hypertension (PAH). Intermedin/adrenomedullin-2 (IMD/AM2) belongs to the Calcitonin Gene-Related Peptide (CGRP)/Adrenomedullin (AM) superfamily. These peptides act via Calcitonin-Like Receptors (CLR) combined with one of three Receptor activity-modifying proteins (RAMPs). IMD/AM2 is a potent pulmonary vasodilator in animal studies. The aim was to describe expression of IMD/AM2, AM and receptor components in human pulmonary vascular cells and to elucidate effects of IMD/AM2 on human PSM migration and PF proliferation. Gene expression was detected by immunofluorescence, immunoblotting and qRT-PCR. Normotension and hypertension were simulated by applying pulsatile mechanical stretch (Flexcell® apparatus). Viable cell numbers were determined by dye exclusion. PSM chemotaxis was measured via Dunn chamber. IMD/AM2 protein was co-expressed with AM and their receptor components in pulmonary artery and microvascular endothelial (PAEC, PMVEC) and non-endothelial cells (PF, PSM), and localised to vesicles. IMD/AM2 was secreted under basal conditions, most abundantly from PF and PMVEC. Secretion from PF and PSM was enhanced by stretch. IMD/AM2 mRNA expression increased in response to hypertensive stretch of PSM. IMD/AM2 inhibited PDGF (10-7 M)-mediated PSM migration maximally at 3 × 10-10 M and PF proliferation maximally at 3 × 10-9 M. Angiotensin II (5 × 10-8 M), normotensive and hypertensive stretch augmented PF proliferation. IMD/AM2 (10-9 M) abolished the proliferative effects of Angiotensin II and normotensive stretch and attenuated the proliferative effect of hypertensive stretch alone and combined with angiotensin II. These findings indicate an important counter-regulatory role for IMD/AM2 in PAH.
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Affiliation(s)
- David Holmes
- School of Medicine, Dentistry and Biomedical Sciences, The Queen's University of Belfast, Northern Ireland, United Kingdom
| | - Michael Corr
- School of Medicine, Dentistry and Biomedical Sciences, The Queen's University of Belfast, Northern Ireland, United Kingdom
| | - Gavin Thomas
- School of Medicine, Dentistry and Biomedical Sciences, The Queen's University of Belfast, Northern Ireland, United Kingdom
| | - Mark Harbinson
- School of Medicine, Dentistry and Biomedical Sciences, The Queen's University of Belfast, Northern Ireland, United Kingdom
| | - Malcolm Campbell
- School of Medicine, Dentistry and Biomedical Sciences, The Queen's University of Belfast, Northern Ireland, United Kingdom
| | - Paul Spiers
- School of Medicine, Dentistry and Biomedical Sciences, The Queen's University of Belfast, Northern Ireland, United Kingdom
| | - David Bell
- School of Medicine, Dentistry and Biomedical Sciences, The Queen's University of Belfast, Northern Ireland, United Kingdom.
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Palus K, Całka J. Influence of Acrylamide Administration on the Neurochemical Characteristics of Enteric Nervous System (ENS) Neurons in the Porcine Duodenum. Int J Mol Sci 2019; 21:ijms21010015. [PMID: 31861419 PMCID: PMC6982244 DOI: 10.3390/ijms21010015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 12/13/2019] [Accepted: 12/15/2019] [Indexed: 12/23/2022] Open
Abstract
The digestive tract, especially the small intestine, is one of the main routes of acrylamide absorption and is therefore highly exposed to the toxic effect of acrylamide contained in food. The aim of this experiment was to elucidate the effect of low (tolerable daily intake—TDI) and high (ten times higher than TDI) doses of acrylamide on the neurochemical phenotype of duodenal enteric nervous system (ENS) neurons using the pig as an animal model. The experiment was performed on 15 immature gilts of the Danish Landrace assigned to three experimental groups: control (C) group—pigs administered empty gelatine capsules, low dose (LD) group—pigs administered capsules with acrylamide at the TDI dose (0.5 μg/kg body weight (b.w.)/day), and the high dose (HD) group—pigs administered capsules with acrylamide at a ten times higher dose than the TDI (5 μg/kg b.w./day) with a morning feeding for 4 weeks. Administration of acrylamide, even in a low (TDI) dose, led to an increase in the percentage of enteric neurons immunoreactive to substance P (SP), calcitonin gene-related peptide (CGRP), galanin (GAL), neuronal nitric oxide synthase (nNOS), and vesicular acetylcholine transporter (VACHT) in the porcine duodenum. The severity of the changes clearly depended on the dose of acrylamide and the examined plexus. The obtained results suggest the participation of these neuroactive substances in acrylamide-inducted plasticity and the protection of ENS neurons, which may be an important line of defence from the harmful action of acrylamide.
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Palus K, Obremski K, Bulc M, Całka J. The impact of low and high doses of acrylamide on the intramural neurons of the porcine ileum. Food Chem Toxicol 2019; 132:110673. [PMID: 31302221 DOI: 10.1016/j.fct.2019.110673] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/08/2019] [Accepted: 07/10/2019] [Indexed: 12/13/2022]
Abstract
The present study was designed to assess the influence of acrylamide supplementation, in tolerable daily intake (TDI) dose and a dose ten times higher than TDI, on the neurochemical phenotype of the ENS neurons and synthesis of proinflammatory cytokines in the wall of the porcine ileum. The study was performed on 15 juvenile female Danish Landrace pigs, divided into three groups: C group- animals receiving empty gelatine capsules, LD group- animals receiving capsules with the TDI dose (0.5 μg/kg b.w./day) of acrylamide and HD group- animals receiving acrylamide in a dose ten times higher than the TDI (5 μg/kg b.w./day) in a morning meal for 28 days. It was established that supplementation of acrylamide led to an increase in substance P (SP)-, calcitonin gene-related peptide (CGRP)-, galanin (GAL)- and vesicular acetylcholine transporter (VAChT)-like immunoreactive (LI) neurons as well as a decrease in neuronal nitric oxide synthase (nNOS) -like immunoreactivity in all types of ileum intramural plexuses. Moreover, using ELISA method, an increase in the level of proinflammatory cytokines (IL-1β, IL-6 and TNF- α) was noted in the ileum wall. The results suggest that SP, CGRP, GAL, nNOS and VACHT participate in the regulation of inflammatory conditions induced by acrylamide supplementation.
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Affiliation(s)
- Katarzyna Palus
- Department of Clinical Physiology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowskiego Str. 13, 10- 718, Olsztyn, Poland.
| | - Kazimierz Obremski
- Department of Veterinary Prevention and Feed Hygiene, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowskiego Str. 13, 10-718, Olsztyn, Poland
| | - Michał Bulc
- Department of Clinical Physiology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowskiego Str. 13, 10- 718, Olsztyn, Poland
| | - Jarosław Całka
- Department of Clinical Physiology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowskiego Str. 13, 10- 718, Olsztyn, Poland
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Aikawa J, Uchida K, Takano S, Inoue G, Iwase D, Miyagi M, Mukai M, Shoji S, Sekiguchi H, Takaso M. Regulation of calcitonin gene-related peptide expression through the COX-2/mPGES-1/PGE2 pathway in the infrapatellar fat pad in knee osteoarthritis. Lipids Health Dis 2018; 17:215. [PMID: 30205824 PMCID: PMC6134514 DOI: 10.1186/s12944-018-0864-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 09/04/2018] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND The infrapatellar fat pad (IFP) is implicated in knee osteoarthritis (KOA). Calcitonin gene-related peptide (CGRP), a vasoactive neuropeptide expressed in joint tissues and synovial tissues (ST), was recently found to be associated with KOA progression and pain. CGRP is expressed in the IFPs of human KOA patients; however, its regulation has not been elucidated. METHODS IFPs and STs were harvested from 138 KOA patients during total knee replacement (TKR) and analyzed for CGRP, cycloxygenase-2 (COX-2), and microsomal prostaglandin E synthase-1 (mPGES-1) expression using real-time polymerase chain reaction (PCR). To investigate CGRP regulation by prostaglandin E2 (PGE2), adipocytes (Ad) and the stromal vascular fraction (SVF) were harvested from IFPs using collagenase. Synovial cells (SYC) were also harvested from ST and stimulated with vehicle (serum-free culture medium), PGE2, or CGRP. RESULTS CGRP, COX-2, and mPGES-1 expression levels were significantly higher in IFPs than STs. PGE2 stimulation increased CGRP expression in Ad, the SVF, and SYC; however, CGRP expression was significantly higher in PGE2-stimulated SVF than PGE2-stimulated SYC. CGRP stimulation had no effect on COX-2 or mPGES-1 expression. CONCLUSIONS CGRP expression in the IFP of KOA patients is regulated by the COX-2/mPGES-1/PGE2 pathway.
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Affiliation(s)
- Jun Aikawa
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Kentaro Uchida
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan.
| | - Shotaro Takano
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Gen Inoue
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Dai Iwase
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Masayuki Miyagi
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Manabu Mukai
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Shintaro Shoji
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Hiroyuki Sekiguchi
- Shonan University of Medical Sciences Research Institute, Nishikubo 500, Chigasaki City, Kanagawa, 253-0083, Japan
| | - Masashi Takaso
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
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Makowska K, Gonkowski S. The Influence of Inflammation and Nerve Damage on the Neurochemical Characterization of Calcitonin Gene-Related Peptide-Like Immunoreactive (CGRP-LI) Neurons in the Enteric Nervous System of the Porcine Descending Colon. Int J Mol Sci 2018; 19:ijms19020548. [PMID: 29439512 PMCID: PMC5855770 DOI: 10.3390/ijms19020548] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 02/07/2018] [Accepted: 02/10/2018] [Indexed: 12/21/2022] Open
Abstract
The enteric nervous system (ENS), localized in the wall of the gastrointestinal tract, regulates the functions of the intestine using a wide range of neuronally-active substances. One of them is the calcitonin gene-related peptide (CGRP), whose participation in pathological states in the large intestine remains unclear. Therefore, the aim of this study was to investigate the influence of inflammation and nerve damage using a double immunofluorescence technique to neurochemically characterize CGRP-positive enteric nervous structures in the porcine descending colon. Both pathological factors caused an increase in the percentage of CGRP-positive enteric neurons, and these changes were the most visible in the myenteric plexus after nerve damage. Moreover, both pathological states change the degree of co-localization of CGRP with other neurochemical factors, including substance P, the neuronal isoform of nitric oxide synthase, galanin, cocaine- and amphetamine-regulated transcript peptide and vesicular acetylcholine transporter. The character and severity of these changes depended on the pathological factor and the type of enteric plexus. The obtained results show that CGRP-positive enteric neurons are varied in terms of neurochemical characterization and take part in adaptive processes in the descending colon during inflammation and after nerve damage.
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Affiliation(s)
- Krystyna Makowska
- Department of Clinical Physiology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowski Str. 13, 10-718 Olsztyn, Poland.
| | - Slawomir Gonkowski
- Department of Clinical Physiology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowski Str. 13, 10-718 Olsztyn, Poland.
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Bai YX, Fang F, Jiang JL, Xu F. Extrinsic Calcitonin Gene-Related Peptide Inhibits Hyperoxia-Induced Alveolar Epithelial Type II Cells Apoptosis, Oxidative Stress, and Reactive Oxygen Species (ROS) Production by Enhancing Notch 1 and Homocysteine-Induced Endoplasmic Reticulum Protein (HERP) Expression. Med Sci Monit 2017; 23:5774-5782. [PMID: 29206808 PMCID: PMC5728081 DOI: 10.12659/msm.904549] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background Lung alveolar epithelial type II cells (AEC II) are the most important stem cells in lung tissues, which are critical for wound repair of bronchopulmonary dysplasia (BPD). This study investigated the effects of calcitonin gene-related peptide (CGRP) on AEC II cells exposed to hyperoxia. Material/Methods Neonatal rat AEC II cells were isolated and identified by detecting surfactant protein C (SP-C). Three small interfering RNAs targeting Notch 1 were synthesized and transfected into AEC II. A hyperoxia-exposed AEC II cell injury model was established and was divided into 8 groups. MDA levels and SOD activity were examined using lipid peroxidation assay kits. Apoptosis and reactive oxygen species (ROS) production were evaluated using flow cytometry. Notch 1 mRNA expression was examined using RT-PCR. Homocysteine-induced endoplasmic reticulum protein (HERP) was examined using Western blot analysis. Results CGRP treatment significantly enhanced MDA levels and decreased SOD activity compared to hyperoxia-treated AEC II cells (P<0.05). CGRP treatment significantly inhibited hyperoxia-induced AEC II cell apoptosis, and significantly suppressed hyperoxia-induced ROS production compared to hyperoxia-treated AEC II cells (P<0.05) either undergoing γ secretase inhibitor or Notch RNA interference. CGRP significantly triggered Notch 1 mRNA expression and significantly enhanced HERP expression compared to hyperoxia-treated AEC II cells (P<0.05) either undergoing γ secretase inhibitor or Notch RNA interference. Conclusions In AEC II cells, extrinsic peptide CGRP suppressed hyperoxia-induced apoptosis, oxidative stress, and ROS production, which may be triggered by Notch 1 and HERP signaling pathway.
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Affiliation(s)
- Yu-Xin Bai
- Department of Critical Care, Children's Hospital of Chongqing Medical University, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing, China (mainland).,Chongqing Key Laboratory of Pediatrics, Chongqing, China (mainland)
| | - Fang Fang
- Department of Critical Care, Children's Hospital of Chongqing Medical University, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing, China (mainland).,Chongqing Key Laboratory of Pediatrics, Chongqing, China (mainland)
| | - Jia-Ling Jiang
- Department of Pediatrics, Inner Mongolia People's Hospital, Hohhot, Inner Mongolia, China (mainland)
| | - Feng Xu
- Department of Critical Care, Children's Hospital of Chongqing Medical University, Ministry of Education Key Laboratory of Child Development and Disorders, China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing, China (mainland).,Chongqing Key Laboratory of Pediatrics, Chongqing, China (mainland)
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Takano S, Uchida K, Inoue G, Minatani A, Miyagi M, Aikawa J, Iwase D, Onuma K, Mukai M, Takaso M. Increase and regulation of synovial calcitonin gene-related peptide expression in patients with painful knee osteoarthritis. J Pain Res 2017; 10:1099-1104. [PMID: 28546767 PMCID: PMC5436753 DOI: 10.2147/jpr.s135939] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Background Recent studies suggest that the vasodilatory neuropeptide calcitonin gene-related peptide (CGRP) is localized in the synovial tissue and may be involved in the pathology of hip and knee osteoarthritis (OA). However, the regulation and relationship between pain and CGRP expression levels in the synovial tissue of human OA patients are not fully understood. Methods Synovial tissues were harvested from 74 participants with radiographic knee OA (unilateral Kellgren/Lawrence grades 3–4) during total knee arthroplasty. CGRP-expressing cells in the resected tissue were identified by immunohistochemical analyses. To examine CGRP expression levels, CD14-positive (CD14+) (macrophage-rich cell fraction) and CD14-negative (CD14−; fibroblast-rich cell fraction) cells were isolated from the synovial tissue. To investigate the involvement of prostaglandin E2 (PGE2) in the regulation of CGRP expression, cultured CD14− and CD14+ cells were stimulated with PGE2. In addition, CGRP expression levels in the synovial tissue of OA patients with strong/severe (visual analog scale [VAS]≥6) and mild/moderate pain (VAS<6) were compared. Results CGRP-positive cells were detected in the intimal lining layer and comprised both CD14− and CD14+ cells. CGRP expression in non-cultured CD14− fractions was significantly higher than that in CD14+ fractions. The expression levels of CGRP were significantly increased in cultured CD14− cell fractions treated with exogenous PGE2, compared to untreated CD14− cell fractions. In contrast, treatment with PGE2 did not increase CGRP regardless of whether or not CD14+ cells expressed CGRP. Furthermore, CGRP expression in the VAS≥6 group was also significantly higher than that in the VAS<6 group. Conclusion These findings suggest that CGRP expression in the synovial fibroblasts is regulated by the COX-2/PGE2 pathway and that elevation of synovial CGRP levels may contribute to OA pain.
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Affiliation(s)
- Shotaro Takano
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
| | - Kentaro Uchida
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
| | - Gen Inoue
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
| | - Atsushi Minatani
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
| | - Masayuki Miyagi
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
| | - Jun Aikawa
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
| | - Dai Iwase
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
| | - Kenji Onuma
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
| | - Manabu Mukai
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
| | - Masashi Takaso
- Department of Orthopedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan
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Aikawa J, Uchida K, Takano S, Inoue G, Minatani A, Miyagi M, Iwase D, Sekiguchi H, Mukai M, Takaso M. Expression of calcitonin gene-related peptide in the infrapatellar fat pad in knee osteoarthritis patients. J Orthop Surg Res 2017; 12:65. [PMID: 28431586 PMCID: PMC5399802 DOI: 10.1186/s13018-017-0568-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 04/13/2017] [Indexed: 11/23/2022] Open
Abstract
Background The infrapatellar fat pad (IPFP) has been implicated as a possible source of osteoarthritis (OA) development and knee pain due to the production of inflammatory mediators and the existence of nerve fibers within this structure. Calcitonin gene-related peptide (CGRP) is a vasodilatory neuropeptide that is localized to joint tissues and has recently been implicated in the development of knee OA and OA pain. To date, however, the expression levels of CGRP in the IPFP of human knee OA patients have not been examined. Methods IFFP and synovial (SYN) tissues were harvested from 100 individuals with radiographic knee OA (unilateral Kellgren/Lawrence [K/L] grades 2–4) during total knee arthroplasty and subjected to immunohistochemical analysis for CGRP localization. In addition, the messenger RNA (mRNA) expression levels of CGRP and cyclooxygenase-2 (COX-2) in the collected tissues were evaluated and compared using real-time PCR analysis of total RNA extracts. CGRP and COX-2 mRNA expression were also compared among individuals with K/L grades 2–4. Results CGRP-positive cells were detected in the capillaries within the IPFP and lining layer of SYN tissue. The expression levels of CGRP in the IPFP were positively correlated with COX-2 and were significantly higher than those in SYN tissue. CGRP expression in tissue from the KL4 group was twofold higher than that from the KL2 group. Conclusions The IPFP of knee OA patients produces relatively high levels of CGRP, which may be regulated by COX-2 at the transcriptional level. Further studies are needed to determine if CGRP levels are directly linked to OA pathology.
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Affiliation(s)
- Jun Aikawa
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan
| | - Kentaro Uchida
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan.
| | - Shotaro Takano
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan
| | - Gen Inoue
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan
| | - Atsushi Minatani
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan
| | - Masayuki Miyagi
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan
| | - Dai Iwase
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan
| | - Hiroyuki Sekiguchi
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan
| | - Manabu Mukai
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan
| | - Masashi Takaso
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara, Kanagawa, 252-0374, Japan
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Minatani A, Uchida K, Inoue G, Takano S, Aikawa J, Miyagi M, Fujimaki H, Iwase D, Onuma K, Matsumoto T, Takaso M. Activation of calcitonin gene-related peptide signaling through the prostaglandin E2-EP1/EP2/EP4 receptor pathway in synovium of knee osteoarthritis patients. J Orthop Surg Res 2016; 11:117. [PMID: 27751171 PMCID: PMC5067902 DOI: 10.1186/s13018-016-0460-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 09/28/2016] [Indexed: 02/24/2023] Open
Abstract
BACKGROUND Calcitonin gene-related peptide (CGRP) is a 37-amino-acid vasodilatory neuropeptide that binds to receptor activity-modifying protein 1 (RAMP1) and the calcitonin receptor-like receptor (CLR). Clinical and preclinical evidence suggests that CGRP is associated with hip and knee joint pain; however, the regulation mechanisms of CGRP/CGRP receptor signaling in synovial tissue are not fully understood. METHODS Synovial tissues were harvested from 43 participants with radiographic knee osteoarthritis (OA; unilateral Kellgren/Lawrence (K/L) grades 3-4) during total knee arthroplasty. Correlationships between the mRNA expression levels of CGRP and those of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and cycloxygenase-2 (COX-2) were evaluated using real-time PCR analysis of total RNA extracted from the collected synovial tissues. To investigate the factors controlling the regulation of CGRP and CGRP receptor expression, cultured synovial cells were stimulated with TNF-α, IL-1β, IL-6, and prostaglandin E2 (PGE2) and were also treated with PGE2 receptor (EP) agonist. RESULTS CGRP and COX-2 localized in the synovial lining layer. Expression of COX-2 positively correlated with CGRP mRNA expression in the synovial tissue of OA patients. The gene expression of CGRP and RAMP1 increased significantly in synovial cells exogenously treated with PGE2 compared to untreated control cells. In cultured synovial cells, CGRP gene expression increased significantly following EP4 agonist treatment, whereas RAMP1 gene expression increased significantly in the presence of exogenously added EP1 and EP2 agonists. CONCLUSIONS PGE2 appears to regulate CGRP/CGRP receptor signaling through the EP receptor in the synovium of knee OA patients.
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Affiliation(s)
- Atsushi Minatani
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Kentaro Uchida
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan.
| | - Gen Inoue
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Shotaro Takano
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Jun Aikawa
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Masayuki Miyagi
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Hisako Fujimaki
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Dai Iwase
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Kenji Onuma
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Toshihide Matsumoto
- Department of Pathology, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
| | - Masashi Takaso
- Department of Orthopedic Surgery, Kitasato University School of Medicine, 1-15-1 Minami-ku Kitasato, Sagamihara City, Kanagawa, 252-0374, Japan
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11
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Kay AB, Ying S, Ardelean E, Mlynek A, Kita H, Clark P, Maurer M. Calcitonin gene-related peptide and vascular endothelial growth factor are expressed in lesional but not uninvolved skin in chronic spontaneous urticaria. Clin Exp Allergy 2015; 44:1053-60. [PMID: 24902612 DOI: 10.1111/cea.12348] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 04/21/2014] [Accepted: 05/14/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND The mechanisms for producing weals in chronic spontaneous (idiopathic) urticaria (CSU) are incompletely understood. Leucocyte infiltration with vascular leakage and expression of the potent vasoactive agents' calcitonin gene-related peptide (CGRP) and vascular endothelial growth factor (VEGF) are features of late-phase allergic skin reactions, previously proposed as a model of CSU. OBJECTIVE To measure CGRP and VEGF expression in lesional and non-lesional skin from CSU patients and to compare results with a control group. METHODS Eight paired biopsies (one from 4-8 h spontaneous weals and one from uninvolved skin) were taken from eight patients with CSU and nine control subjects and studied by immunohistochemistry and confocal microscopy. RESULTS Lesional skin in CSU contained significantly more CGRP+ and VEGF+ cells than non-lesional skin. No significant differences were observed in CGRP and VEGF expression between non-lesional skin and controls. In lesional skin, VEGF and CGRP co-localised to UEA-1+ blood vessels. CGRP was also expressed by neutrophils and eosinophils and to a lesser extent by CD90(+) fibroblasts, mast cells, CD3(+) and CD68(+) cells. CGRP and VEGF expression was not related to the duration of disease. CONCLUSION AND CLINICAL RELEVANCE Increased expression of CGRP and VEGF in lesional, but not uninvolved, skin indicates that these potent vasoactive agents may play a role in wealing and tissue oedema in CSU so representing novel targets in therapy.
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Affiliation(s)
- A B Kay
- Leukocyte Biology Section, National Heart & Lung Institute, Imperial College London, London, UK
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12
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Dang H, Yang L, Wang S, Fang F, Xu F. Calcitonin gene-related peptide ameliorates hyperoxia-induced lung injury in neonatal rats. TOHOKU J EXP MED 2013; 227:129-38. [PMID: 22706400 DOI: 10.1620/tjem.227.129] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Therapies with prolonged exposure to high-concentration oxygen are common in the treatment of critical pulmonary and cardiac conditions in newborns. However, prolonged exposure to hyperoxia could result in lung damages and developmental disorders manifested as acute lung injury and bronchopulmonary dysplasia, respectively. Calcitonin gene-related peptide (CGRP) has been shown to have a broad regulatory effect on the respiratory system. In this study, we explored the protective effects of CGRP on the hyperoxia-induced lung damage. Newborn Sprague-Dawley rats were randomly divided into three groups: normoxia, hyperoxia, and hyperoxia with CGRP. Hyperoxia groups were exposed to 95% oxygen for 14 days and treated once every other day with saline or CGRP. Hyperoxia exposure reduced the survival rate to 73%, when compared with the 93% survival rate observed in the normoxia group. The survival rate was improved to 84% with CGRP treatment. Treatment with CGRP under hyperoxia significantly alleviated the hyperoxia-induced lung histomorphological changes and the increases in leukocyte counts and total protein levels in bronchoalveolar lavage fluid that reflect the pulmonary microvasular damages. CGRP treatment also restored the decreased activity of superoxide dismutase, while it decreased the increased level of malondialdehyde in the lung tissues. Importantly, CGRP treatment significantly decreased the magnitude of the hyperoxia-mediated increase in the expression levels of tumor necrosis factor-α mRNA and transforming growth factor-β 1 protein. In conclusion, the hyperoxia-induced acute lung injury is associated with both oxidative stress and inflammatory responses, and CGRP may ameliorate the hyperoxia-induced lung injury by down-regulating these processes.
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Affiliation(s)
- Hongxing Dang
- Pediatric Intensive Care Unit, Children's Hospital of Chongqing Medical University, Yu Zhong District, Chongqing, P.R. China
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Interleukin-1β Inhibits Voltage-Gated Sodium Currents in a Time- and Dose-Dependent Manner in Cortical Neurons. Neurochem Res 2011; 36:1116-23. [DOI: 10.1007/s11064-011-0456-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2011] [Indexed: 01/21/2023]
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14
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Kay AB. Calcitonin gene-related peptide- and vascular endothelial growth factor-positive inflammatory cells in late-phase allergic skin reactions in atopic subjects. J Allergy Clin Immunol 2011; 127:232-7. [PMID: 21211657 DOI: 10.1016/j.jaci.2010.10.028] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Revised: 10/14/2010] [Accepted: 10/18/2010] [Indexed: 11/16/2022]
Abstract
BACKGROUND Allergen-induced late-phase skin reactions are characterized by erythema and edema, but the vasoactive mediators involved remain unclear. Limited evidence from human studies suggests that calcitonin gene-related peptide (CGRP) and vascular endothelial growth factor (VEGF), potent vasodilator and permeability factors, respectively, are expressed by infiltrating inflammatory cells in certain allergic tissue reactions. OBJECTIVE We sought to determine whether tissue swelling in allergen-challenged skin sites in atopic subjects is associated with the infiltration of CGRP(+) and VEGF(+) inflammatory cells. METHODS Skin biopsy specimens were obtained from atopic subjects at various times after cutaneous allergen challenge and studied by means of single and double immunohistochemistry and in situ hybridization. RESULTS CGRP-immunoreactive and CGRP mRNA-positive cell numbers were increased in biopsy specimens from sites of late-phase skin reactions compared with those at the control site (P = .03 and P = .03, respectively). Their numbers paralleled the development and resolution of the edematous late-phase skin reaction, both peaking at 6 hours after allergen challenge. The majority of CGRP-immunoreactive cells were neutrophils and CD3(+) cells, whereas eosinophils were CGRP negative. VEGF-immunopositive cell numbers were also increased in 6-hour biopsy specimens from late-phase skin reactions compared with those seen at control sites (P = .001) with a lesser but significant response (P = .008) at 24 hours. VEGF(+) cells were largely eosinophils, neutrophils, and CD68(+) macrophages. CONCLUSIONS Late-phase skin reactions in atopic subjects were associated with the infiltration of inflammatory cells expressing CGRP and VEGF, suggesting that these vasoactive factors might play a role in the erythema and edema characteristic of allergic inflammation. They could also be considered targets in attempts to control allergic inflammation.
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Affiliation(s)
- A Barry Kay
- Leukocyte Biology Section, National Heart & Lung Institute, Imperial College London, London, United Kingdom.
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15
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Bonner K, Kariyawasam HH, Ali FR, Clark P, Kay AB. Expression of functional receptor activity modifying protein 1 by airway epithelial cells with dysregulation in asthma. J Allergy Clin Immunol 2010; 126:1277-83.e3. [PMID: 20933260 DOI: 10.1016/j.jaci.2010.08.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 07/02/2010] [Accepted: 08/02/2010] [Indexed: 11/19/2022]
Abstract
BACKGROUND Epithelial cell expression of calcitonin gene-related peptide (CGRP) is a feature of provoked asthma. Receptor activity modifying protein 1 (RAMP1) and the calcitonin receptor-like receptor combine to form the CGRP1 receptor. OBJECTIVE To determine whether functional RAMP1 is expressed by airway epithelial cells and whether there are alterations in asthma. METHODS BEAS-2B and A549 cells lines were studied by RT-PCR, confocal microscopy, a quantitative immunofluorescence assay, and ELISA. Bronchial biopsies from normal subjects and subjects with asthma were examined by immunohistochemistry and in situ hybridization. RESULTS Inflammatory cytokines induced CGRP release and CGRP mRNA in BEAS-2B and A549 epithelial cell lines. RAMP1 was highly expressed by resting, unstimulated BEAS-2B and A549 cells. CGRP induced internalization of RAMP1 and IL-6 production, both of which were inhibited by the CGRP antagonist, CGRP(8-37). Activation of BEAS-2B and A549 cells by inflammatory cytokines induced CGRP secretion, binding of CGRP to RAMP1, and RAMP1 internalization, which was blocked by CGRP (8-37). RAMP1 immunoreactivity and RAMP1 mRNA expression in bronchial biopsies from subjects with asthma were significantly lower than in normal subjects (P = .002 and P = .007, respectively). Inhalational challenge of atopic subjects with asthma with allergen-derived peptides produced a significant decrease in the numbers of RAMP1-positive epithelial cells in responders (P = .027) but not nonresponders. CONCLUSION Receptor activity modifying protein 1 was expressed both by airway epithelial cells in culture and in bronchial biopsies from normal subjects and internalized after epithelial cell activation through autocrine feedback of CGRP. There is an apparent dysregulation of RAMP1 in asthmatic epithelium, suggesting continuous stimulation of pathways involving CGRP.
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Affiliation(s)
- Kandace Bonner
- Leukocyte Biology Section, National Heart and Lung Institute, Faculty of Medicine, Imperial College London, United Kingdom
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16
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Helyes Z, Elekes K, Sándor K, Szitter I, Kereskai L, Pintér E, Kemény A, Szolcsányi J, McLaughlin L, Vasiliou S, Kipar A, Zimmer A, Hunt SP, Stewart JP, Quinn JP. Involvement of preprotachykinin A gene-encoded peptides and the neurokinin 1 receptor in endotoxin-induced murine airway inflammation. Neuropeptides 2010; 44:399-406. [PMID: 20579732 DOI: 10.1016/j.npep.2010.05.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 04/28/2010] [Accepted: 05/28/2010] [Indexed: 11/28/2022]
Abstract
Tachykinins encoded by the preprotachykinin A (TAC1) gene such as substance P (SP) and neurokinin A (NKA) are involved in neurogenic inflammatory processes via predominantly neurokinins 1 and 2 (NK1 and NK2) receptor activation, respectively. Endokinins and hemokinins encoded by the TAC4 gene also have remarkable selectivity and potency for the NK1 receptors and might participate in inflammatory cell functions. The aim of the present study was to investigate endotoxin-induced airway inflammation and consequent bronchial hyper-reactivity in TAC1(-/-), NK1(-/-) and also in double knockout (TAC1(-/-)/NK1(-/-)) mice. Sub-acute interstitial lung inflammation was evoked by intranasal Escherichia coli lipopolysaccharide (LPS) in the knockout mice and their wildtype C57BL/6 counterparts 24 h before measurement. Respiratory parameters were measured with unrestrained whole body plethysmography. Bronchoconstriction was induced by inhalation of the muscarinic receptor agonist carbachol and Penh (enhanced pause) correlating with airway resistance was calculated. Lung interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) concentrations were measured with ELISA. Histological evaluation was performed and a composite morphological score was determined. Myeloperoxidase (MPO) activity in the lung was measured with spectrophotometry to quantify the number of infiltrating neutrophils/macrophages. Airway hyper-reactivity was significantly reduced in the TAC1(-/-) as well as the TAC1(-/-)/NK1(-/-) groups. However, LPS-induced histological inflammatory changes (perivascular/peribronchial oedema, neutrophil infiltration and goblet cell hyperplasia), MPO activity and TNF-alpha concentration were markedly diminished only in TAC1(-/-) mice. Interestingly, the concentrations of both cytokines, IL-1beta and TNF-alpha, were significantly greater in the NK1(-/-) group. These data clearly demonstrated on the basis of histology, MPO and cytokine measurements that TAC1 gene-derived tachykinins, SP and NKA, play a significant role in the development of endotoxin-induced murine airway inflammation, but not solely via NK1 receptor activation. However, in inflammatory bronchial hyper-responsiveness other tachykinins, such as hemokinin-1 acting through NK1 receptors also might be involved.
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Affiliation(s)
- Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, University of Pécs, Hungary.
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Ma W, Dumont Y, Vercauteren F, Quirion R. Lipopolysaccharide induces calcitonin gene-related peptide in the RAW264.7 macrophage cell line. Immunology 2010; 130:399-409. [PMID: 20141542 DOI: 10.1111/j.1365-2567.2009.03239.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
SUMMARY Calcitonin gene-related peptide (CGRP) is widely distributed and plays important roles in a wide array of biological functions. It is enriched in primary sensory neurons and hence involved in nociception and neurogenic inflammation. Recent studies have shown that CGRP can be produced by immune cells such as monocytes/macrophages following inflammatory stimulation, suggesting a role in innate immunity. However, it is unclear how CGRP is up-regulated in macrophages and if it plays a role in macrophage functions such as the production of cytokines and chemokines. Using enzyme-linked immunosorbent assay (ELISA) and multiplex ELISA, lipopolysaccharide (LPS) was found to induce CGRP in the RAW 264.7 macrophage cell line. LPS-induced inflammatory mediators such as nerve growth factor (NGF), interleukin-1beta (IL-1beta), IL-6, prostaglandin E(2) (PGE(2)) and nuclear factor-kappaB (NF-kappaB) signalling are involved in inducing CGRP, whereas the NGF receptor trkA and CGRP receptor signalling pathways are unexpectedly involved in suppressing LPS-induced CGRP, which leads to the fine-tune regulation of CGRP release. Exogenous CGRP and CGRP receptor antagonists, in a concentration-dependent manner, stimulated, inhibited or had no effect on basal or LPS-induced release of monocyte chemoattractant protein-1, IL-1beta, IL-6, tumour necrosis factor-alpha and IL-10 in RAW macrophages. The ligand-concentration-dependent regulation of the production of inflammatory mediators by CGRP receptor signalling is a novel mechanism underlying the stimulating and suppressing role of CGRP in immune and inflammatory responses. Together, our data suggest that monocytes/macrophages are an important source of CGRP. Inflammation-induced CGRP has a positive or negative reciprocal effect on the production of other pro- and anti-inflammatory mediators. Thereby CGRP plays both facilitating and suppressing roles in immune and inflammatory responses.
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Affiliation(s)
- Weiya Ma
- Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada.
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de Mos M, Laferrière A, Millecamps M, Pilkington M, Sturkenboom MCJM, Huygen FJPM, Coderre TJ. Role of NFkappaB in an animal model of complex regional pain syndrome-type I (CRPS-I). THE JOURNAL OF PAIN 2010; 10:1161-9. [PMID: 19878863 DOI: 10.1016/j.jpain.2009.04.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2008] [Revised: 03/10/2009] [Accepted: 04/19/2009] [Indexed: 12/23/2022]
Abstract
UNLABELLED NFkappaB is involved in several pathogenic mechanisms that are believed to underlie the complex regional pain syndrome (CRPS), including ischemia, inflammation and sensitization. Chronic postischemia pain (CPIP) has been developed as an animal model that mimics the symptoms of CRPS-I. The possible involvement of NFkappaB in CRPS-I was studied using CPIP rats. Under sodium pentobarbital anesthesia, a tourniquet was placed around the rat left ankle joint, producing 3 hours of ischemia, followed by rapid reperfusion (IR injury). NFkappaB was measured in nuclear extracts of muscle and spinal cord tissue using ELISA. Moreover, the anti-allodynic (mechanical and cold) effect was tested for systemic, intrathecal, or intraplantar treatment with the NFkappaB inhibitor pyrrolidine dithiocarbamate (PDTC). At 2 and 48 hours after IR injury, NFkappaB was elevated in muscle and spinal cord of CPIP rats compared to shams. At 7 days, NFkappaB levels were normalized in muscle, but still elevated in spinal cord tissue. Systemic PDTC treatment relieved mechanical and cold allodynia in a dose-dependent manner, lasting for at least 3 hours. Intrathecal-but not intraplantar-administration also relieved mechanical allodynia. The results suggest that muscle and spinal NFkappaB plays a role in the pathogenesis of CPIP and potentially of human CRPS. PERSPECTIVE Using the CPIP model, we demonstrate that NFkappaB is involved in the development of allodynia after a physical injury (ischemia and reperfusion) without direct nerve trauma. Since CPIP animals exhibit many features of human CRPS-I, this observation indicates a potential role for NFkappaB in human CRPS.
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Affiliation(s)
- Marissa de Mos
- Department of Medical Informatics & Epidemiology and Biostatistics, Erasmus Medical Center, Rotterdam, the Netherlands.
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Zhang YM, Peng J, Hu CP, Jiang QT, Jiang GL, Li YJ. Clonidine induces calcitonin gene-related peptide expression via nitric oxide pathway in endothelial cells. Peptides 2009; 30:1746-52. [PMID: 19520131 DOI: 10.1016/j.peptides.2009.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2009] [Revised: 05/30/2009] [Accepted: 06/01/2009] [Indexed: 11/25/2022]
Abstract
The present study was to determine whether clonidine could induce calcitonin gene-related peptide (CGRP) production and the underlying mechanisms. Human umbilical vein endothelial cells were treated with clonidine and the dose-effect or time-effect relationship of clonidine on CGRP production was examined. Yohimbine (a alpha(2)-adrenoceptor blocker) and L-NAME (an antagonist of nitric oxide synthase, NOS) were chosen to explore the role of alpha(2)-adrenoceptor and nitric oxide pathway in the effect of clonidine on endothelial cell-derived CGRP production. The level of CGRP mRNA or protein was detected by Real Time-PCR or radioimmunoassay. Nitric oxide content was measured by nitroreduction assay. The study showed that clonidine was able to induce CGRP mRNA (alpha- and beta-isoforms) expression in a dose-dependent manner in endothelial cells. The effect of clonidine on endothelial cell-derived CGRP synthesis and secretion was attenuated in the presence of yohimbine. L-NAME treatment could also inhibit clonidine-induced CGRP synthesis and secretion concomitantly with the decreased NO content in culture medium. These results suggest that clonidine could stimulate CGRP synthesis and secretion in endothelial cells through the activation of alpha(2)-adrenoceptor, which is related to the NO pathway.
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Affiliation(s)
- Yi-Min Zhang
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, 110 Xiang-Ya Road, Changsha, Hunan, China
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Kawanami Y, Morimoto Y, Kim H, Nakamura T, Machida K, Kido T, Asonuma E, Yatera K, Yoshii C, Kido M. Calcitonin gene-related peptide stimulates proliferation of alveolar epithelial cells. Respir Res 2009; 10:8. [PMID: 19192276 PMCID: PMC2651852 DOI: 10.1186/1465-9921-10-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2008] [Accepted: 02/03/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Alveolar epithelial cells are known as progenitor cells for the restoration from the damage in the lung. Calcitonin gene-related peptide (CGRP) has been reported to play an important role in the proliferation of various types of epithelial and endothelial cells. We investigated the effects of CGRP on the proliferation of alveolar epithelial cells in vitro and in vivo. METHODS A549 cells were cultured in Dulbecco Modified Eagle Medium with 5% fatal bovin serum for 24 hours, then CGRP was added in vitro. The proliferation of DNA synthesis was measured using 5-bromo-2-deoxyuridine, an analog of thymidine, by enzyme-linked immunosorbent assay.As one intracellular response to CGRP, we examined activation of p44/42- extracellular signal-regulated kinase (ERK) pathway by adding CGRP, using western blotting method.Recombinant adenovirus encoding nuclear-targeted-human beta-CGRP (rhCGRP) was administered into Male Wister rat (n = 5, 10 weeks old) lungs by intratracheal instillation in vivo. 7 days after the administration of CGRP, rat lungs were harvested and histological findings and immunohistochemical staining of proliferating cell nuclear antigen (PCNA) were evaluated to examine cell proliferation. RESULTS In vitro study, CGRP increased the proliferation of A549 cells in a dose and time dependent manner. CGRP8-37 (inhibitor of CGRP receptor) decreased CGRP induced proliferation of DNA synthesis. Phosphorylation of ERK pathway was observed within 15 minutes and peaked in one hour. U0126 (inhibitor of ERK pathway) decreased CGRP induced proliferation of DNA synthesis.In vivo study, histological examination of the lung indicated proliferation of alveolar epithelial cells in the rhCGRP-treated group and the nuclei of alveolar epithelial cells were positive for PCNA immunostaining. CONCLUSION In this study, we conclude that CGRP stimulates proliferation of human alveolar epithelial cells in vivo and in vitro.
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Affiliation(s)
- Yukiko Kawanami
- Department of Respiratory Disease, University of Occupational and Environmental Health, Japan, Kitakyushu City, Fukuoka, Japan.
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Luo D, Zhang YW, Peng WJ, Peng J, Chen QQ, Li D, Deng HW, Li YJ. Transient receptor potential vanilloid 1-mediated expression and secretion of endothelial cell-derived calcitonin gene-related peptide. ACTA ACUST UNITED AC 2008; 150:66-72. [PMID: 18584893 DOI: 10.1016/j.regpep.2008.05.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 04/16/2008] [Accepted: 05/19/2008] [Indexed: 10/22/2022]
Abstract
Calcitonin gene-related peptide (CGRP), the principal transmitter in sensory nerves, could also be expressed in vascular endothelium. Transient receptor potential vanilloid 1(TRPV1), which modulates the synthesis and release of CGRP in sensory nerves, is also present in endothelial cells. The present study tested whether TRPV1 modulates the release and synthesis of CGRP in endothelial cells, and evaluated the protective effect of endothelial cell-derived CGRP. Human umbilical vein endothelial cells (HUVECs) were treated with capsaicin or hyperthermia. The level of CGRP mRNA was detected by RT-PCR, and protein level was measured by radioimmunoassay. Endothelial cell injury was induced by lysophosphatidylcholine, and evaluated by cell viability and lactate dehydrogenase activity. HUVECs expressed CGRP, both alpha- and beta-subtype. Capsaicin increased the level of CGRP in the culture medium, and up-regulated the expression of CGRP in endothelial cells. Hyperthermia also increased the level of CGRP mRNA. These effects were abolished by capsazepine, a competitive antagonist of TRPV1. Capsaicin significantly attenuated the endothelial cell damage induced by LPC, which was prevented and aggravated by capsazepine or CGRP(8-37,) antagonist of CGRP receptor. These results indicate that TRPV1 also regulates the expression and secretion of endothelial cell-derived CGRP, which affords protective effects on endothelial cells.
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Affiliation(s)
- Dan Luo
- Department of Pharmacology, School of Pharmaceutical Sciences, Central South University, Changsha, Hunan 410078, China.
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Li W, Zheng S, Tang C, Zhu Y, Wang X. JNK-AP-1 pathway involved in interleukin-1beta-induced calcitonin gene-related peptide secretion in human type II alveolar epithelial cells. Peptides 2007; 28:1252-9. [PMID: 17481780 DOI: 10.1016/j.peptides.2007.03.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Revised: 03/27/2007] [Accepted: 03/27/2007] [Indexed: 12/17/2022]
Abstract
In a previous study, we found that calcitonin gene-related peptide (CGRP) could be induced by proinflammatory factor IL-1beta in A549 human type II alveolar (AEII) epithelial cells. We investigated the mechanism of IL-1beta-induced CGRP secretion and found that the PKC-p38 MAPK-NF-kappaB pathway was involved. In the present study, we found that IL-1beta stimulation induced c-Jun N-terminal kinase (JNK) activity within 15min in A549 cells. In investigating whether JNK was involved in IL-1beta-induced CGRP secretion, the JNK II inhibitor SP600125 was used and it significantly attenuated IL-1beta-induced CGRP secretion and c-Jun activity, which was elevated after IL-1beta stimulation from mRNA to protein level. EMSA results showed the activation of activator protein 1 (AP-1) after 2-h IL-1beta stimulation, and the JNK II inhibitor blocked c-Jun and AP-1 activity. Bioinformatic analysis showed five predicted AP-1 binding sites on the promoter of beta-CGRP; deletion analysis identified an AP-1 consensus site at -643bp relative to the initiation site, which mediates the beta-CGRP gene transcription in response to IL-1beta. These data suggest that besides the PKC-p38 MAPK-NF-kappaB pathway, the JNK-AP-1 pathway is involved in IL-1beta-induced CGRP secretion in A549 human type II alveolar epithelial cells, and a 643-bp site upstream of the transcription start site on the promoter of beta-CGRP is the AP-1 response element.
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Affiliation(s)
- Wenjing Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences; Reference Laboratory of Education Ministry on Molecular Cardiology, Health Science Center, Peking University, Beijing 100083, PR China
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Elekes K, Helyes Z, Németh J, Sándor K, Pozsgai G, Kereskai L, Börzsei R, Pintér E, Szabó A, Szolcsányi J. Role of capsaicin-sensitive afferents and sensory neuropeptides in endotoxin-induced airway inflammation and consequent bronchial hyperreactivity in the mouse. ACTA ACUST UNITED AC 2007; 141:44-54. [PMID: 17291600 DOI: 10.1016/j.regpep.2006.12.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Revised: 12/15/2006] [Accepted: 12/16/2006] [Indexed: 01/09/2023]
Abstract
Substance P (SP) and calcitonin gene-related peptide (CGRP) released from capsaicin-sensitive afferents induce neurogenic inflammation via NK(1), NK(2) and CGRP1 receptor activation. This study examines the role of capsaicin-sensitive fibres and sensory neuropeptides in endotoxin-induced airway inflammation and consequent bronchial hyperreactivity with functional, morphological and biochemical techniques in mice. Carbachol-induced bronchoconstriction was measured with whole body plethysmography 24 h after intranasal lipopolysaccharide administration. SP and CGRP were determined with radioimmunoassay, myeloperoxidase activity with spectrophotometry, interleukin-1beta with ELISA and histopathological changes with semiquantitative scoring from lung samples. Treatments with resiniferatoxin for selective destruction of capsaicin-sensitive afferents, NK(1) antagonist SR 140333, NK(2) antagonist SR 48968, their combination, or CGRP1 receptor antagonist CGRP(8-37) were performed. Lipopolysaccharide significantly increased lung SP and CGRP concentrations, which was prevented by resiniferatoxin pretreatment. Resiniferatoxin-desensitization markedly enhanced inflammation, but decreased bronchoconstriction. CGRP(8-37) or combination of SR 140333 and SR 48968 diminished neutrophil accumulation, MPO levels and IL-1beta production, airway hyperresponsiveness was inhibited only by SR 48968. This is the first evidence that capsaicin-sensitive afferents exert a protective role in endotoxin-induced airway inflammation, but contribute to increased bronchoconstriction. Activation of CGRP1 receptors or NK(1)+NK(2) receptors participate in granulocyte accumulation, but NK(2) receptors play predominant role in enhanced airway resistance.
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Affiliation(s)
- Krisztián Elekes
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Pécs, H-7624 Pécs, Szigeti u. 12., Hungary
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Chen M, Li W, Wang N, Zhu Y, Wang X. ROS and NF-kappaB but not LXR mediate IL-1beta signaling for the downregulation of ATP-binding cassette transporter A1. Am J Physiol Cell Physiol 2006; 292:C1493-501. [PMID: 17135302 DOI: 10.1152/ajpcell.00016.2006] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
ATP-binding cassette transporter A1 (ABCA1), a pivotal regulator of cholesterol efflux from cells to apolipoproteins, plays an important role in cholesterol homeostasis. As an inflammatory factor, IL-1beta has been shown to downregulate ABCA1 in macrophages and facilitates foam cell formation. However, the molecular mechanism underlining the downregulated ABCA1 by IL-1beta is still elusive. In the present study, we demonstrated that IL-1beta downregulated ABCA1 but not ABCG1 at mRNA and protein levels in a time- and dose-dependent manner in THP-1 and A549 cells. IL-1beta attenuated ABCA1 promoter activity through an LXR (liver X receptor)-independent pathway, since IL-1beta did not alter the expression and activities of LXRalpha/beta, and deletion of the LXR responsive element from the ABCA1 promoter failed to reverse the IL-1beta effect. In contrast, NF-kappaB inhibition by pyrrolidine dithiocarbamate and MG132 prevented the suppression of ABCA1 by IL-1beta. Cotransfection with ABCA1 luciferase reporter and the expression plasmids of Rel A decreased ABCA1 promoter activities. An adenovirus expressing NF-kappaB inhibitor subunit-alpha inhibited NF-kappaB activities and also reversed the IL-1beta effect at the promoter activity and protein levels of ABCA1. In addition, IL-1beta could induce the production of reactive oxygen species (ROS), and N-acetyl-L-cysteine, a scavenger of ROS, reversed the decreased level of ABCA1 induced by IL-1beta. H(2)O(2) decreased ABCA1 at the mRNA and protein levels and the promoter activity. Thus our data provide strong evidence that ROS and NF-kappaB, but not LXR, mediate the IL-1beta-induced downregulation of ABCA1 via a novel transcriptional mechanism, which might play an important role of proinflammation in the alteration of lipid metabolism.
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Affiliation(s)
- Min Chen
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences and Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University, Beijing 100083, People's Republic of China
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Dai J, Li W, Chang L, Zhang Z, Tang C, Wang N, Zhu Y, Wang X. Role of redox factor-1 in hyperhomocysteinemia-accelerated atherosclerosis. Free Radic Biol Med 2006; 41:1566-77. [PMID: 17045925 DOI: 10.1016/j.freeradbiomed.2006.08.020] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Revised: 08/21/2006] [Accepted: 08/23/2006] [Indexed: 02/03/2023]
Abstract
Hyperhomocysteinemia (HHcy) is an independent risk factor for atherosclerosis. We have previously shown that homocysteine can induce monocyte chemoattractant protein-1 (MCP-1) secretion via reactive oxygen species (ROS) in human monocytes in vitro. In the present study, we investigated whether redox factor-1 (Ref-1) is involved in HHcy-accelerated atherosclerosis. We used a mild HHcy animal model, aortic roots and peritoneal macrophages were isolated for immunohistochemistry and Western blotting, from apoE-/- and C57BL/6J mice fed a high Hcy diet (1.8 g/L) for 4 or 12 weeks. Four-week HHcy apoE-/- mice showed more plaques and significantly increased immunostaining of Ref-1 and MCP-1 in foam cells, and HHcy mice showed enhanced Ref-1 expression in peritoneal macrophages. To explore the mediating mechanism, incubation with Hcy (100 microM) increased Ref-1 protein level and translocation in human monocytes in vitro. In addition, Hcy-induced NADPH oxidase activity mediated the upregulation of Ref-1. Furthermore, overexpressed Ref-1 upregulated NF-kappaB and MCP-1 promoter activity, and antisense Ref-1 reduced Hcy-induced NF-kappaB DNA-binding activity and MCP-1 secretion. These data indicate that Hcy-induced ROS upregulate the expression and translocation of Ref-1 via NADPH oxidase, and then Ref-1 increases NF-kappaB activity and MCP-1 secretion in human monocytes/macrophages, which may accelerate the development of atherosclerosis.
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Affiliation(s)
- Jing Dai
- Department of Physiology and Pathophysiology, School of Basic Medical Science, Peking University, Beijing 100083, People's Republic of China
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Li W, Wang T, Ma C, Xiong T, Zhu Y, Wang X. Calcitonin gene-related peptide inhibits interleukin-1beta-induced endogenous monocyte chemoattractant protein-1 secretion in type II alveolar epithelial cells. Am J Physiol Cell Physiol 2006; 291:C456-65. [PMID: 16597919 DOI: 10.1152/ajpcell.00538.2005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
As important multifunctional cells in the lung, alveolar epithelial type II (AEII) cells secrete numerous chemokines on various stimuli. Our previous data showed that AEII cells also express the neuropeptide calcitonin gene-related peptide (CGRP) and the proinflammatory factor interleukin (IL)-1beta induces CGRP secretion in the A549 human AEII cell line. In the present study, the CGRP-1 receptor antagonist human (h)CGRP(8-37) (0.1-1 nM) greatly amplified the production of IL-1beta-induced monocyte chemoattractant protein (MCP)-1. The inhibition of CGRP expression by small interfering RNA significantly increased MCP-1 secretion on IL-1beta stimulation. However, exogenous hCGRP (10-100 nM) suppressed IL-1beta-evoked MCP-1 secretion in MCP-1 promoter activity, and CGRP gene stably transfected cell clones significantly inhibited both the mRNA and protein levels of MCP-1 induced by IL-1beta. These data imply that AEII-derived CGRP suppressed IL-1beta-induced MCP-1 secretion in an autocrine/paracrine mode. Subsequent investigation revealed that CGRP inhibited IL-1beta-evoked NF-kappaB activity by suppressing IkappaBalpha phosphorylation and degradation. Moreover, CGRP attenuated IL-1beta-induced reactive oxygen species (ROS) formation, the early event in proinflammatory factor signaling. We previously showed that the CGRP inhibitory effect was mediated by elevated intracellular cAMP and show here that analogs of cAMP, 8-bromoadenosine 3',5'-cyclic monophosphothioate and the Sp isomer of adenosine 3',5'-cyclic monophosphothioate, mimicked the CGRP suppressive effect on IL-1beta-induced ROS formation, NF-kappaB activation, and MCP-1 secretion. Thus increased endogenous CGRP secretion in lung inflammatory disease might eliminate the excessive response by elevating the cAMP level through inhibiting the ROS-NF-kappaB-MCP-1 pathway.
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Affiliation(s)
- Wenjing Li
- Department of Physiology and Pathophysiology, School of Basic Medical Science, Peking University, Xue Yuan Road No. 38, Beijing 100083, People's Republic of China
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Wang W, Jia L, Wang T, Sun W, Wu S, Wang X. Endogenous Calcitonin Gene-related Peptide Protects Human Alveolar Epithelial Cells through Protein Kinase Cϵ and Heat Shock Protein. J Biol Chem 2005; 280:20325-30. [PMID: 15784626 DOI: 10.1074/jbc.m413864200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The intracellular mechanisms of ischemic preconditioning (PC) in preventing lung dysfunction following transplantation, shock, and trauma remain poorly understood. Previously, we have shown that alveolar epithelial cells secrete calcitonin gene-related peptide (CGRP) under inflammatory stress. Using a hypoxia/reoxygenation (H/R) and PC model, we found that CGRP was also secreted from human type II alveolar epithelial cells (A549) after PC. The locally released CGRP interacted with its receptor on the membrane of A549 cells and elicited downstream signals mediating the PC effect, because hCGRP(8-37), a specific CGRP receptor antagonist, attenuated the protective effect of PC. Pre-inhibition of CGRP protein synthesis by small interfering RNA exacerbated (but overexpression of the CGRP gene ameliorated) H/R-induced cell death, which supports the autocrine effect of CGRP on A549 cells. Exogenous bioactive CGRP mimicked the beneficial effect of PC and up-regulated the expression of heat shock protein 70 (HSP70), which might act as the end effector to maintain cell viability. These effects were sensitive to hCGRP(8-37), calphostin C (a protein kinase C (PKC) inhibitor), and 5-hydroxydecanoic acid (a mitochondrial K(+)(ATP) channel blocker) but were insensitive to protein kinase A blockers. Moreover, CGRP induced the membrane translocation of PKCepsilon. PKCV1-2 (a cell-permeable inhibitory peptide of PKCepsilon) effectively abolished CGRP-induced HSP70 expression and cell protection. Therefore, PC induces CGRP secretion from human alveolar epithelial cells, and the locally released CGRP acts back on these cells, protecting them from H/R injury. The post-receptor signaling of CGRP is through PKCepsilon-dependent expression of HSP70.
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Affiliation(s)
- Wang Wang
- Institute of Vascular Medicine, Peking University Third Hospital, Beijing 100083, China
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