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Toh P, Nicholson JL, Vetter AM, Berry MJ, Torres DJ. Selenium in Bodily Homeostasis: Hypothalamus, Hormones, and Highways of Communication. Int J Mol Sci 2022; 23:15445. [PMID: 36499772 PMCID: PMC9739294 DOI: 10.3390/ijms232315445] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/30/2022] [Accepted: 12/04/2022] [Indexed: 12/12/2022] Open
Abstract
The ability of the body to maintain homeostasis requires constant communication between the brain and peripheral tissues. Different organs produce signals, often in the form of hormones, which are detected by the hypothalamus. In response, the hypothalamus alters its regulation of bodily processes, which is achieved through its own pathways of hormonal communication. The generation and transmission of the molecules involved in these bi-directional axes can be affected by redox balance. The essential trace element selenium is known to influence numerous physiological processes, including energy homeostasis, through its various redox functions. Selenium must be obtained through the diet and is used to synthesize selenoproteins, a family of proteins with mainly antioxidant functions. Alterations in selenium status have been correlated with homeostatic disturbances in humans and studies with animal models of selenoprotein dysfunction indicate a strong influence on energy balance. The relationship between selenium and energy metabolism is complicated, however, as selenium has been shown to participate in multiple levels of homeostatic communication. This review discusses the role of selenium in the various pathways of communication between the body and the brain that are essential for maintaining homeostasis.
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Affiliation(s)
- Pamela Toh
- Pacific Biosciences Research Center, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - Jessica L. Nicholson
- Pacific Biosciences Research Center, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822, USA
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA
| | - Alyssa M. Vetter
- Pacific Biosciences Research Center, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822, USA
- School of Human Nutrition, McGill University, Montreal, QC H3A 0G4, Canada
| | - Marla J. Berry
- Pacific Biosciences Research Center, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822, USA
| | - Daniel J. Torres
- Pacific Biosciences Research Center, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, HI 96822, USA
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Shi X, Pan S, Li L, Li Y, Ma W, Wang H, Xu C, Li L, Wang D. HIX003209 promotes vascular smooth muscle cell migration and proliferation through modulating miR-6089. Aging (Albany NY) 2020; 12:8913-8922. [PMID: 32463793 PMCID: PMC7288934 DOI: 10.18632/aging.103079] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 03/24/2020] [Indexed: 12/14/2022]
Abstract
Accumulating references have showed that long noncoding RNAs (lncRNAs) act important roles in the development of human diseases. The role and expression of HIX003209 remains unclear in the pathogenesis of atherosclerosis. We showed that HIX003209 expression was upregulated in atherosclerotic coronary tissues compared to normal coronary artery samples. HIX003209 was overexpressed in vascular smooth muscle cells (VSMCs) induced by inflammatory mediators including tumor necrosis factor-α(TNF-α), ox-LDL and latelet-derived growth factor-BB (PDGF-BB). Ectopic expression of HIX003209 enhanced cell growth and migration and induced inflammatory mediators secretion such as interleukin 6 (IL-6), TNF-α and IL-1β in VSMCs. Furthermore, we showed that miR-6089 was downregulated in atherosclerotic coronary tissues compared to normal coronary artery samples. There was a negative association between expression of HIX003209 and miR-6089 in atherosclerotic coronary tissues. MiR-6089 expression was decreased in VSMCs induced by inflammatory mediators including TNF-α, ox-LDL and PDGF-BB. Dual luciferase analysis showed that miR-6089 overexpression decreased luciferase activity of HIX003209 WT-type 3’-UTR but not the mut-type 3’-UTR. Overexpression of HIX003209 suppressed the expression of miR-6089 in VSMCs. Ectopic expression of HIX003209 induced cell growth, migration and the secretion of inflammatory mediators via regulating miR-6089 expression. These data suggested that HIX003209 promoted VSMCs proliferation, migration and the secretion of inflammatory mediators partly via regulating miR-6089.
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Affiliation(s)
- Xiaofeng Shi
- Department of Emergency, Tianjin First Center Hospital, Tianjin 300192, People's Republic of China
| | - Shuang Pan
- Department of Physiology, School of Basic Medicine, Jinzhou Medicine University, Jinzhou 121000, Liaoning, People's Republic of China
| | - Li Li
- Clinical Nutrition Department, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, Liaoning, People's Republic of China
| | - Yongqi Li
- Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba 3050005, Japan
| | - Wei Ma
- Department of Anatomy, Dalian Medical University, Dalian 116044, Liaoning, People's Republic of China
| | - Han Wang
- Department of Vascular Surgery, Dalian University Affiliated Xinhua Hospital, Dalian 116021, Liaoning, People's Republic of China
| | - Caiming Xu
- Department of General Surgery, The First Affiliated Hospital, Dalian Medical University, Dalian 116011, Liaoning, People's Republic of China
| | - Lei Li
- Department of Vascular Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, Liaoning, People's Republic of China
| | - Dong Wang
- Neurosurgery Department, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027, Liaoning, People's Republic of China
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Lee EJ, Song KJ, Hwang HJ, Kim KS. Effectiveness of atorvastatin in suppressingMUC5ACgene expression in human airway epithelial cells. Int Forum Allergy Rhinol 2016; 6:1159-1166. [DOI: 10.1002/alr.21811] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Revised: 05/12/2016] [Accepted: 05/22/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Eun Jung Lee
- Department of Otorhinolaryngology; Yonsei University College of Medicine; Seoul Korea
| | - Kee Jae Song
- Department of Otorhinolaryngology; Catholic Kwandong University; International St. Mary's Hospital Incheon Korea
| | - Hye Jin Hwang
- Department of Otorhinolaryngology; Yonsei University College of Medicine; Seoul Korea
| | - Kyung-Su Kim
- Department of Otorhinolaryngology; Yonsei University College of Medicine; Seoul Korea
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Effects of angiotensin II on leptin and downstream leptin signaling in the carotid body during acute intermittent hypoxia. Neuroscience 2015; 310:430-41. [DOI: 10.1016/j.neuroscience.2015.09.066] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 08/11/2015] [Accepted: 09/24/2015] [Indexed: 11/19/2022]
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Hsu JH, Liou SF, Yang SN, Wu BN, Dai ZK, Chen IJ, Yeh JL, Wu JR. B-type natriuretic peptide inhibits angiotensin II-induced proliferation and migration of pulmonary arterial smooth muscle cells. Pediatr Pulmonol 2014; 49:734-44. [PMID: 24167111 DOI: 10.1002/ppul.22904] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 06/21/2013] [Accepted: 08/13/2013] [Indexed: 01/10/2023]
Abstract
Pulmonary vascular remodeling, characterized by disordered proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs), is a pathognomonic feature of pulmonary arterial hypertension. Thus, pharmacologic strategy targeting on anti-proliferation and anti-migration of PASMCs may have therapeutic implications for PAH. Here we investigated the effects and underlying mechanisms of B-type natriuretic peptide (BNP) on angiotensin II (Ang II)-induced proliferation and migration of PASMCs. Proliferation and migration of PASMCs cultured from Wistar rats were induced by Ang II, with or without BNP treatment. In addition, potential underlying mechanisms including cell cycle progression, Ca(2+) overload, reactive oxygen species (ROS) production, signal transduction of MAPK and Akt, and the cGMP/PKG pathway were examined. We found that BNP inhibited Ang II-induced PASMCs proliferation and migration dose dependently. BNP could also arrest the cell cycle progression in the G0/G1-phase. In addition, BNP attenuated intracellular calcium overload caused by Ang II. Moreover, Ang II-induced ROS production was mitigated by BNP, with associated down-regulation of NAD(P)H oxidase 1 (Nox1) and reduced mitochondrial ROS production. Finally, Ang II-activated MAPKs and Akt were also counteracted by BNP. Of note, all these effects of BNP were abolished by a PKG inhibitor (Rp-8-Br-PET-cGMPS). In conclusion, BNP inhibits Ang II-induced PASMCs proliferation and migration. These effects are potentially mediated by decreased calcium influx, reduced ROS production by Nox1 and mitochondria, and down-regulation of MAPK and Akt signal transduction, through the cGMP/PKG pathway. Therefore, this study implicates that BNP may have a therapeutic role in pulmonary vascular remodeling.
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Affiliation(s)
- Jong-Hau Hsu
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Pediatrics, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
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Liu J, Ren Y, Kang L, Zhang L. Oxidized low-density lipoprotein increases the proliferation and migration of human coronary artery smooth muscle cells through the upregulation of osteopontin. Int J Mol Med 2014; 33:1341-7. [PMID: 24590381 DOI: 10.3892/ijmm.2014.1681] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 02/21/2014] [Indexed: 11/06/2022] Open
Abstract
Smooth muscle cell (SMC) proliferation and migration are known to play a critical role in the development of atherosclerosis. Oxidized low-density lipoprotein (oxLDL) is involved in the generation of atherosclerotic lesions. Recent studies have indicated that oxLDL is a well-established risk factor for atherosclerosis that induces vascular smooth muscle cell (VSMC) proliferation and migration; however, the exact mechanisms involved have not been fully elucidated. In this study, the proliferation of human coronary artery smooth muscle cells (HCASMCs) was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell migration was determined by Transwell assay. Osteopontin (OPN), matrix metaloproteinase-9 (MMP-9) and αvβ3 integrin expression were measured by mRNA and western blot analysis. OPN and MMP-9 knockdown cells were established through transfection with OPN siRNA or MMP-9 siRNA, respectively. Our results revealed that oxLDL makredly promoted HCASMC proliferation and migration in a dose-dependent manner. Further experiments demonstrated that oxLDL upregulated the expression of OPN and oxLDL. Cell proliferation and migration were markedly reduced following the knockdown of the OPN gene in the HCASMCs. We then found that treatment with oxLDL induced a concentration-dependent increase in MMP-9 mRNA and protein levels in the HCASMCs. These effects were partially abrogated by silencing OPN expression or blocking the αvβ3 integrin pathway. Moreover, cells treated with MMP-9 siRNA or αvβ3 antibody showed lower proliferation and migration rates. This study provides direct in vitro evidence that the exposure of HCASMCs to oxLDL induces the activation of OPN, leading to higher protein levels of MMP-9, and to an increased proliferation and migration of HCASMCs.
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Affiliation(s)
- Jun Liu
- Department of Geriatrics, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Yingang Ren
- Department of Geriatrics, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Li Kang
- Department of Geriatrics, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
| | - Lihua Zhang
- Department of Geriatrics, Tangdu Hospital, The Fourth Military Medical University, Xi'an, Shaanxi 710038, P.R. China
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Angiotensin II and the ERK pathway mediate the induction of leptin by mechanical cyclic stretch in cultured rat neonatal cardiomyocytes. Clin Sci (Lond) 2014; 126:483-95. [PMID: 24063596 DOI: 10.1042/cs20130235] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Mechanical cyclic stretch of cardiomyocytes causes cardiac hypertrophy through cardiac-restricted gene expression. Leptin induces cardiomyocyte hypertrophy in response to myocardial stress. In the present study, we evaluated the expression of leptin under cyclic stretch and its role in regulating genetic transcription in cardiomyocytes. Cultured rat neonatal cardiomyocytes were subjected to cyclic stretch, and the expression levels of leptin, ROS (reactive oxygen species) and AngII (angiotensin II) were evaluated. Signal transduction inhibitors were used to identify the pathway of leptin expression. EMSAs were used to identify the binding of leptin/STAT3 (signal transducer and activator of transcription 3) and luciferase assays were used to identify the transcription of leptin in cardiomyocytes. The study also used an in vivo model of AV (aortocaval) shunt in rats to investigate leptin, ROS and AngII expression. Leptin and leptin receptor levels increased after cyclic stretch with the earlier expression of AngII and ROS. Leptin expression was suppressed by AngII receptor blockers, an ROS scavenger [NAC (N-acetylcysteine)], an ERK (extracellular-signal-regulated kinase) pathway inhibitor (PD98059) and ERK siRNA. Binding of leptin/STAT3 was identified by EMSAs, and luciferase assays confirmed the transcription of leptin in neonatal cardiomyocytes after cyclic stretch. Increased MHC (myosin heavy chain) expression and [3H]-proline incorporation in cardiomyocytes was detected after cyclic stretch, which were inhibited by leptin siRNA and NAC. The in vivo model of AV shunt also demonstrated increased levels of plasma and myocardial leptin, ROS and AngII expression after cyclic stretch. Mechanical cyclic stretch in cardiomyocytes increased leptin expression mediated by the induction of AngII, ROS and the ERK pathway to cause cardiomyocyte hypertrophy. Myocardial hypertrophy can be identified by increased transcriptional activity and an enhanced hypertrophic phenotype of cardiomyocytes.
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Lin CM, Hou SW, Wang BW, Ong JR, Chang H, Shyu KG. Molecular mechanism of (-)-epigallocatechin-3-gallate on balloon injury-induced neointimal formation and leptin expression. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2014; 62:1213-1220. [PMID: 24410132 DOI: 10.1021/jf404479x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Leptin contributes to the pathogenesis of vascular repair and cardiovascular events. This study evaluated the molecular mechanism of EGCG in balloon injury-induced leptin expression. According to immunohistochemical and confocal analyses, leptin expression was increased and the aortic lumen exhibited narrowing after balloon injury. EGCG treatment attenuated leptin expression and diminished neointimal formation. The in vitro study showed that angiotensin II (Ang II) induced the migration and proliferation of cultured vascular smooth muscle cells (VSMCs), whereas treatment with EGCG, leptin siRNA, and c-Jun siRNA inhibited the migration and proliferation of VSMCs significantly. The EMSA shows that balloon injury increased AP-1-binding activity, and EGCG and c-Jun siRNA inhibited the AP-1-binding activity. Western blot and real-time RT-PCR analyses revealed similar results in intimal tissue samples. In summary, balloon injury induces leptin expression in the carotid artery of rats, and EGCG inhibits leptin expression through the JNK/AP-1 pathway and also attenuates neointimal formation.
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Affiliation(s)
- Chiu-Mei Lin
- Department of Emergency Medicine, Shin Kong Wu Ho-Su Memorial Hospital , Taipei, Taiwan
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Gene expression signature of human HepG2 cell line. Gene 2013; 518:335-45. [DOI: 10.1016/j.gene.2012.12.106] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 12/21/2012] [Accepted: 12/24/2012] [Indexed: 01/12/2023]
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Suski M, Gębska A, Olszanecki R, Stachowicz A, Uracz D, Madej J, Korbut R. Influence of atorvastatin on angiotensin I metabolism in resting and TNF-α -activated rat vascular smooth muscle cells. J Renin Angiotensin Aldosterone Syst 2013; 15:378-83. [PMID: 23390189 DOI: 10.1177/1470320313475907] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION Vascular smooth muscle cells (VSMCs) are essential for maintaining vasculature homeostasis and function. By influence on its growth and activation both proinflammatory cytokines and peptides of the renin-angiotensin system (RAS) are potent regulators of VSMCs. Interestingly, angiotensin (Ang) II and Ang-(1-7) elicit opposite effects on VSMC activation, differentiation and proliferation. It has been suggested that statins, besides anti-inflammatory effects, may also modulate VSMC activation by their influence on the RAS. METHODS The effect of atorvastatin on Ang I metabolism in a culture of explanted rat VSMCs was examined by liquid chromatography-mass spectrometry (LC-MS); expression of mRNA of the main RAS enzymes in VSMC was assessed by real-time polymerase chain reaction (PCR). RESULTS In VSMC culture Ang-(1-7) was identified as a major product of Ang I metabolism. In this setting, TNF-α (1 ng/ml) caused a decrease in the conversion of Ang I to Ang-(1-7). This effect was accompanied by a decrease of mRNA expression of neutral endopeptidase (NEP) and angiotensin converting enzyme 2 (ACE2) and increase of mRNA of ACE. Interestingly, atorvastatin (3 μM) attenuated the effects of TNF-α on Ang-(1-7) production as well as reversed the influence of TNF-α on ACE and ACE2 expression. CONCLUSIONS Enhancement by atorvastatin of the ACE2/Ang-(1-7) axis in VSMCs could represent a new and beneficial mechanism on cardiovascular action of this widely used drug.
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Affiliation(s)
- Maciej Suski
- School of Medicine, Jagiellonian University, Poland
| | - Anna Gębska
- School of Medicine, Jagiellonian University, Poland
| | | | | | - Danuta Uracz
- School of Medicine, Jagiellonian University, Poland
| | - Jozef Madej
- School of Medicine, Jagiellonian University, Poland
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Basu S, Nachat-Kappes R, Caldefie-Chézet F, Vasson MP. Eicosanoids and adipokines in breast cancer: from molecular mechanisms to clinical considerations. Antioxid Redox Signal 2013; 18:323-60. [PMID: 22746381 DOI: 10.1089/ars.2011.4408] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Chronic inflammation is one of the foremost risk factors for different types of malignancies, including breast cancer. Additional risk factors of this pathology in postmenopausal women are weight gain, obesity, estrogen secretion, and an imbalance in the production of adipokines, such as leptin and adiponectin. Various signaling products of transcription factor, nuclear factor-kappaB, in particular inflammatory eicosanoids, reactive oxygen species (ROS), and cytokines, are thought to be involved in chronic inflammation-induced cancer. Together, these key components have an influence on inflammatory reactions in malignant tissue damage when their levels are deregulated endogenously. Prostaglandins (PGs) are well recognized in inflammation and cancer, and they are solely biosynthesized through cyclooxygenases (COXs) from arachidonic acid. Concurrently, ROS give rise to bioactive isoprostanes from arachidonic acid precursors that are also involved in acute and chronic inflammation, but their specific characteristics in breast cancer are less demonstrated. Higher aromatase activity, a cytochrome P-450 enzyme, is intimately connected to tumor growth in the breast through estrogen synthesis, and is interrelated to COXs that catalyze the formation of both inflammatory and anti-inflammatory PGs such as PGE(2), PGF(2α), PGD(2), and PGJ(2) synchronously under the influence of specific mediators and downstream enzymes. Some of the latter compounds upsurge the intracellular cyclic adenosine monophosphate concentration and appear to be associated with estrogen synthesis. This review discusses the role of COX- and ROS-catalyzed eicosanoids and adipokines in breast cancer, and therefore ranges from their molecular mechanisms to clinical aspects to understand the impact of inflammation.
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Affiliation(s)
- Samar Basu
- Biochemistry, Molecular Biology and Nutrition, University of Auvergne, Clermont-Ferrand, France.
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Schneiderman J, Schaefer K, Kolodgie FD, Savion N, Kotev-Emeth S, Dardik R, Simon AJ, Halak M, Pariente C, Engelberg I, Konstantinides S, Virmani R. Leptin locally synthesized in carotid atherosclerotic plaques could be associated with lesion instability and cerebral emboli. J Am Heart Assoc 2012; 1:e001727. [PMID: 23316287 PMCID: PMC3541612 DOI: 10.1161/jaha.112.001727] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 08/02/2012] [Indexed: 12/11/2022]
Abstract
BACKGROUND Unstable carotid plaques cause cerebral emboli. Leptin promotes atherosclerosis and vessel wall remodeling. We hypothesized that carotid atherosclerotic lesion instability is associated with local leptin synthesis. METHODS AND RESULTS Carotid endarterectomy plaques from symptomatic (n=40) and asymptomatic patients with progressive stenosis (n=38) were analyzed for local expression of leptin, tumor necrosis factor (TNF)-α, and plasminogen activator inhibitor type 1. All lesions exhibited advanced atherosclerosis inclusive of thick- and thin-cap fibroatheromas or lesion rupture. Symptomatic lesions exhibited more plaque ruptures and macrophage infiltration (P=0.001 and P=0.05, respectively). Symptomatic plaques showed preferential leptin, TNF-α, and plasminogen activator inhibitor type 1 transcript (P=0.03, P=0.04, and P=0.05, respectively). Leptin mRNA and antigen in macrophages and smooth muscle cells were confirmed by in situ hybridization and immunohistochemistry. Plasma leptin levels were not significantly different between groups (P=1.0), whereas TNF-α was significantly increased in symptomatic patients (P=0.006). Human aortic smooth muscle cell culture stimulated by TNF-α, lipopolysaccharide, or lipoteichoic acid revealed 6-, 6.7-, and 6-fold increased secreted leptin antigen, respectively, at 72 hours (P<0.05). CONCLUSIONS Neurologically symptomatic patients overexpress leptin mRNA and synthesize leptin protein in carotid plaque macrophages and smooth muscle cells. Local leptin induction, presumably by TNF-α, could exert paracrine or autocrine effects, thereby contributing to the pathogenesis of lesion instability. CLINICAL TRIAL REGISTRATION URL: www.Clinicaltrials.gov. Unique identifier: NCT00449306.
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Affiliation(s)
- Jacob Schneiderman
- Department of Vascular Surgery and the Gottesdiener Vascular Biology Laboratory, Sheba Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Israel.
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