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Contreras S, Escalona R, Cantin C, Valdivia P, Zapata D, Carvajal L, Brito R, Cerda Á, Illanes S, Gutiérrez J, Leiva A. Small extracellular vesicles from pregnant women with maternal supraphysiological hypercholesterolemia impair endothelial cell function in vitro. Vascul Pharmacol 2023; 150:107174. [PMID: 37105374 DOI: 10.1016/j.vph.2023.107174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 04/06/2023] [Accepted: 04/21/2023] [Indexed: 04/29/2023]
Abstract
Maternal physiological hypercholesterolemia (MPH, maternal total cholesterol (TC) levels at term of pregnancy ≤280 mg/dl) occurs to assure fetal development. Maternal supraphysiological hypercholesterolemia (MSPH, TC levels >280 mg/dl) is a pathological condition associated with maternal, placental, and fetal endothelial dysfunction and early neonatal atherosclerosis development. Small extracellular vesicles (sEVs) are delivered to the extracellular space by different cells, where they modulate cell functions by transporting active signaling molecules, including proteins and miRNA. AIM To determine whether sEVs from MSPH women could alter the function of endothelial cells (angiogenesis, endothelial activation and nitric oxide synthesis capacity). METHODS This study included 24 Chilean women (12 MPH and 12 MSPH). sEVs were isolated from maternal plasma and characterized by sEV markers (CD9, Alix and HSP70), nanoparticle tracking analysis, transmission electron microscopy, and protein and cholesterol content. The endothelial cell line HMEC-1 was used to determine the uptake of labeled sEVs and the effects of sEVs on cell viability, endothelial tube formation, endothelial cell activation, and endothelial nitric oxide expression and function. RESULTS In MSPH women, the plasma concentration of sEVs was increased compared to that in MPH women. MSPH-sEVs were highly taken up by HMEC-1 cells and reduced angiogenic capacity and the expression and activity of eNOS without changing cell viability or endothelial activation. CONCLUSION sEVs from MSPH women impair angiogenesis and nitric oxide synthesis in endothelial cells, which could contribute to MSPH-associated endothelial dysfunction.
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Affiliation(s)
- Susana Contreras
- Facultad de Ciencias para el Cuidado de la Salud, Universidad San Sebastián, Santiago, Chile
| | - Rodrigo Escalona
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Claudette Cantin
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Pascuala Valdivia
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - David Zapata
- Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Lorena Carvajal
- Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Roberto Brito
- Center of Excellence in Translational Medicine, CEMT-BIOREN, Universidad de La Frontera, Temuco, Chile
| | - Álvaro Cerda
- Center of Excellence in Translational Medicine, CEMT-BIOREN, Universidad de La Frontera, Temuco, Chile; Departamento de Ciencias Básicas, Universidad de La Frontera, Temuco, Chile
| | | | - Jaime Gutiérrez
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile.
| | - Andrea Leiva
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile.
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Hajtuch J, Iwicka E, Szczoczarz A, Flis D, Megiel E, Cieciórski P, Radomski MW, Santos-Martinez MJ, Inkielewicz-Stepniak I. The Pharmacological Effects of Silver Nanoparticles Functionalized with Eptifibatide on Platelets and Endothelial Cells. Int J Nanomedicine 2022; 17:4383-4400. [PMID: 36164554 PMCID: PMC9507977 DOI: 10.2147/ijn.s373691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/04/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose In the search for new drug delivery platforms for cardiovascular diseases and coating of medical devices, we synthesized eptifibatide-functionalized silver nanoparticles (AgNPs-EPI) and examined the pharmacological activity of AgNPs-EPI on platelets and endothelial cells in vitro and ex vivo. Methods Spherical AgNPs linked to eptifibatide were synthesized and characterized. Cytotoxicity was measured in microvascular endothelial cells (HMEC-1), platelets and red blood cells. Platelet mitochondrial respiration was measured using the Oxygraph-2k, a high-resolution modular respirometry system. The effect of AgNPs-EPI on the aggregation of washed platelets was measured by light aggregometry and the ex vivo occlusion time was determined using a reference laboratory method. The surface amount of platelet receptors such as P-selectin and GPIIb/IIIa was measured. The influence of AgNPS-EPI on blood coagulation science was assessed. Finally, the effect of AgNPs-EPI on endothelial cells was measured by the levels of 6-keto-PGF1alpha, tPa, cGMP and vWF. Results We describe the synthesis of AgNPs using eptifibatide as the stabilizing ligand. The molecules of this drug are directly bonded to the surface of the nanoparticles. The synthesized AgNPs-EPI did not affect the viability of platelets, endothelial cells and erythrocytes. Preincubation of platelets with AgNPs-EPI protected by mitochondrial oxidative phosphorylation capacity. AgNPs-EPI inhibited aggregation-induced P-selectin expression and GPIIb/IIIa conformational changes in platelets. AgNPs-EPI caused prolongation of the occlusion time in the presence of collagen/ADP and collagen/adrenaline. AgNPs-EPI regulated levels of 6-keto-PGF1alpha, tPa, vWf and cGMP produced in thrombin stimulated HMEC-1 cells. Conclusion AgNPs-EPI show anti-aggregatory activity at concentrations lower than those required by the free drug acting via regulation of platelet aggregation, blood coagulation, and endothelial cell activity. Our results provide proof-of-principle evidence that AgNPs may be used as an effective delivery platform for antiplatelet drugs.
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Affiliation(s)
- Justyna Hajtuch
- Department of Pharmaceutical Pathophysiology, Medical University of Gdansk, Gdansk, Poland
| | - Eliza Iwicka
- Department of Pharmaceutical Pathophysiology, Medical University of Gdansk, Gdansk, Poland
| | - Anna Szczoczarz
- Department of Pharmaceutical Pathophysiology, Medical University of Gdansk, Gdansk, Poland
| | - Damian Flis
- Department of Pharmaceutical Pathophysiology, Medical University of Gdansk, Gdansk, Poland
| | | | | | - Marek Witold Radomski
- Department of Anatomy, Physiology and Pharmacology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Maria Jose Santos-Martinez
- School of Pharmacy and Pharmaceutical Sciences and School of Medicine, Trinity College Dublin, Dublin, Dublin 2, Ireland
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Poitou K, Rogez-Florent T, Dirninger A, Corbière C, Monteil C. Effects of DEHP, DEHT and DINP Alone or in a Mixture on Cell Viability and Mitochondrial Metabolism of Endothelial Cells In Vitro. TOXICS 2022; 10:toxics10070373. [PMID: 35878278 PMCID: PMC9316248 DOI: 10.3390/toxics10070373] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 06/30/2022] [Accepted: 07/01/2022] [Indexed: 02/01/2023]
Abstract
Plasticizers are chemicals in high demand, used in a wide range of commercial products. Human are exposed through multiple pathways, from numerous sources, to multiple plasticizers. This is a matter of concern, as it may contribute to adverse health effects. The vascular system carries plasticizers throughout the body and therefore can interact with the endothelium. The aim of the study was to evaluate the in vitro toxicity on endothelial cells by considering the individual and the mixture effects of bis-(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP) or bis-(2-ethylhexyl) terephthalate (DEHT). In this study, their cytotoxicity on HMEC-1 cells was evaluated on cell function (viability, cell counting, total glutathione and intracellular adenosines) and mitochondrial function (mitochondrial respiration). Results showed cellular physiological perturbations induced with all the condition tested, excepted for DEHT. Plasticizers induced a cytotoxicity by targeting mitochondrial respiration, depleting mitochondrial ATP production and increasing glycolytic metabolism. Additionally, delayed effects were observed between the cellular and the mitochondrial parameters. These results suggest that endothelial cells could go through a metabolic adaptation to face plasticizer-induced cellular stress, to effectively maintain their cellular processes. This study provides additional information on the adverse effects of plasticizers on endothelial cells.
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Santiago FS, Li Y, Khachigian LM. Serine 26 in Early Growth Response-1 Is Critical for Endothelial Proliferation, Migration, and Network Formation. J Am Heart Assoc 2021; 10:e020521. [PMID: 34476983 PMCID: PMC8649526 DOI: 10.1161/jaha.120.020521] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background Vascular endothelial cell proliferation, migration, and network formation are key proangiogenic processes involving the prototypic immediate early gene product, Egr‐1 (early growth response‐1). Egr‐1 undergoes phosphorylation at a conserved Ser26 but its function is completely unknown in endothelial cells or any other cell type. Methods and Results A CRISPR/Cas9 strategy was used to introduce a homozygous Ser26>Ala mutation into endogenous Egr‐1 in human microvascular endothelial cells. In the course of generating mutant cells, we produced cells with homozygous deletion in Egr‐1 caused by frameshift and premature termination. We found that Ser26 mutation in Egr‐1, or Egr‐1 deletion, perturbed endothelial cell proliferation in models of cell counting or real‐time growth using the xCELLigence System. We found that Ser26 mutation or Egr‐1 deletion ameliorated endothelial cell migration toward VEGF‐A165 (vascular endothelial growth factor‐A) in a dual‐chamber model. On solubilized basement membrane preparations, Ser26 mutation or Egr‐1 deletion prevented endothelial network (or tubule) formation, an in vitro model of angiogenesis. Flow cytometry further revealed that Ser26 mutation or Egr‐1 deletion elevated early and late apoptosis. Finally, we demonstrated that Ser26 mutation or Egr‐1 deletion increased VE‐cadherin (vascular endothelial cadherin) expression, a regulator of endothelial adhesion and signaling, permeability, and angiogenesis. Conclusions These findings not only indicate that Egr‐1 is essential for endothelial cell proliferation, migration, and network formation, but also show that point mutation in Ser26 is sufficient to impair each of these processes and trigger apoptosis as effectively as the absence of Egr‐1. This highlights the importance of Ser26 in Egr‐1 for a range of proangiogenic processes.
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Affiliation(s)
- Fernando S Santiago
- Vascular Biology and Translational Research School of Medical Sciences UNSW Medicine and HealthUniversity of New South Wales Sydney NSW Australia
| | - Yue Li
- Vascular Biology and Translational Research School of Medical Sciences UNSW Medicine and HealthUniversity of New South Wales Sydney NSW Australia
| | - Levon M Khachigian
- Vascular Biology and Translational Research School of Medical Sciences UNSW Medicine and HealthUniversity of New South Wales Sydney NSW Australia
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Endothelial Cells as Tools to Model Tissue Microenvironment in Hypoxia-Dependent Pathologies. Int J Mol Sci 2021; 22:ijms22020520. [PMID: 33430201 PMCID: PMC7825710 DOI: 10.3390/ijms22020520] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/27/2020] [Accepted: 01/05/2021] [Indexed: 12/11/2022] Open
Abstract
Endothelial cells (ECs) lining the blood vessels are important players in many biological phenomena but are crucial in hypoxia-dependent diseases where their deregulation contributes to pathology. On the other hand, processes mediated by ECs, such as angiogenesis, vessel permeability, interactions with cells and factors circulating in the blood, maintain homeostasis of the organism. Understanding the diversity and heterogeneity of ECs in different tissues and during various biological processes is crucial in biomedical research to properly develop our knowledge on many diseases, including cancer. Here, we review the most important aspects related to ECs’ heterogeneity and list the available in vitro tools to study different angiogenesis-related pathologies. We focus on the relationship between functions of ECs and their organo-specificity but also point to how the microenvironment, mainly hypoxia, shapes their activity. We believe that taking into account the specific features of ECs that are relevant to the object of the study (organ or disease state), especially in a simplified in vitro setting, is important to truly depict the biology of endothelium and its consequences. This is possible in many instances with the use of proper in vitro tools as alternative methods to animal testing.
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Abstract
The prevalence of heart failure (HF), including reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF), has increased significantly worldwide. However, the prognosis and treatment of HF are still not good. Recent studies have demonstrated that high-density lipoprotein (HDL) plays an important role in cardiac repair during HF. The exact role and mechanism of HDL in the regulation of HF remain unexplained. Here, we discuss recent findings regarding HDL in the progression of HF, such as the regulation of excitation-contraction coupling, energy homeostasis, inflammation, neurohormone activation, and microvascular dysfunction. The effects of HDL on the regulation of cardiac-related cells, such as endothelial cells (ECs), cardiomyocytes (CMs), and on cardiac resident immune cell dysfunction in HF are also explained. An in-depth understanding of HDL function in the heart may provide new strategies for the prevention and treatment of HF.
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Xu X, Tian L, Zhang Z. Triptolide inhibits angiogenesis in microvascular endothelial cells through regulation of miR-92a. J Physiol Biochem 2019; 75:573-583. [PMID: 31691162 DOI: 10.1007/s13105-019-00707-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 09/13/2019] [Indexed: 12/15/2022]
Abstract
Atherosclerosis is one common chronic inflammatory disease in which angiogenesis is involved. Here we established an in vitro cell model of angiogenesis made by human dermal microvascular endothelial cells (HMEC-1) and work to investigate the role of triptolide (TPL) in this model. To induce angiogenesis, HMEC-1 cells were cultured in Matrigel-conditioned medium. The ratio of tubes to nucleus was detected. To evaluate angiogenesis, Western blot assay was carried out to detect endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor receptor-2 (VEGFR2) and VEGF. Cell counting kit-8 was utilized to estimate the viability of HMEC-1 cells. microRNA (miR)-92a was analyzed by qRT-PCR. The targeting relationship between integrin subunit alpha 5 (ITGA5) and miR-92a was verified through luciferase activity assay. The effects of ITGA5 on signaling transducers (ERK, PI3K, and AKT) in a phosphorylated form were valued using Western blot method. After stimulated by TPL, LY294002 and PD98059, the alteration in phosphorylation of the signaling transducers was evaluated by Western blot assay. The ratio of tubes to nucleus and angiogenesis related factors were increased with the delaying of culture time. TPL decreased the expression of angiogenesis factors. Furthermore, miR-92a was upregulated by TPL and miR-92a silence upregulated angiogenesis factors. In addition, TPL decreased ITGA5 which was proved as a target of miR-92a. ITGA5 overexpression resulted in the abundance of angiogenesis factors while ITGA5 silence led to the opposite results. Meanwhile, ITGA5 overexpression increased phosphorylation of ERK, PI3K and AKT while ITGA5 silence reversed the trend. TPL (as an anti-angiogenesis agent) suppressed angiogenesis by upregulating miR-92a, and miR-92a-mediated down-regulation of ITGA5 blocked the signaling transduction of ERK and PI3K/AKT pathways.
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Affiliation(s)
- Xiaomeng Xu
- Medical Examination Center of Qilu Hospital of Shandong University, No.107 Culture West Road, Jinan, 250012, Shandong, China.,Department of Health Management, Jining NO.1 People's Hospital, Jining, 272011, Shandong, China
| | - Li Tian
- Department of Critical Care Medicine, Jining NO.1 People's Hospital, Jining, 272011, Shandong, China
| | - Zhimian Zhang
- Medical Examination Center of Qilu Hospital of Shandong University, No.107 Culture West Road, Jinan, 250012, Shandong, China.
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Puumala and Tula Virus Differ in Replication Kinetics and Innate Immune Stimulation in Human Endothelial Cells and Macrophages. Viruses 2019; 11:v11090855. [PMID: 31540120 PMCID: PMC6784088 DOI: 10.3390/v11090855] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 08/23/2019] [Accepted: 09/12/2019] [Indexed: 12/13/2022] Open
Abstract
Old world hantaviruses cause hemorrhagic fever with renal syndrome (HFRS) upon zoonotic transmission to humans. In Europe, the Puumala virus (PUUV) is the main causative agent of HFRS. Tula virus (TULV) is also widely distributed in Europe, but there is little knowledge about the pathogenicity of TULV for humans, as reported cases are rare. We studied the replication of TULV in different cell types in comparison to the pathogenic PUUV and analyzed differences in stimulation of innate immunity. While both viruses replicated to a similar extent in interferon (IFN)-deficient Vero E6 cells, TULV replication in human lung epithelial (A549) cells was slower and less efficient when compared to PUUV. In contrast to PUUV, no replication of TULV could be detected in human microvascular endothelial cells and in macrophages. While a strong innate immune response towards PUUV infection was evident at 48 h post infection, TULV infection triggered only a weak IFN response late after infection of A549 cells. Using appropriate in vitro cell culture models for the orthohantavirus infection, we could demonstrate major differences in host cell tropism, replication kinetics, and innate immune induction between pathogenic PUUV and the presumably non- or low-pathogenic TULV that are not observed in Vero E6 cells and may contribute to differences in virulence.
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Yap J, Cabrera-Fuentes HA, Irei J, Hausenloy DJ, Boisvert WA. Role of Macrophages in Cardioprotection. Int J Mol Sci 2019; 20:E2474. [PMID: 31109146 PMCID: PMC6566352 DOI: 10.3390/ijms20102474] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 05/14/2019] [Accepted: 05/17/2019] [Indexed: 12/21/2022] Open
Abstract
Cardiovascular diseases are the leading cause of mortality worldwide. It is widely known that non-resolving inflammation results in atherosclerotic conditions, which are responsible for a host of downstream pathologies including thrombosis, myocardial infarction (MI), and neurovascular events. Macrophages, as part of the innate immune response, are among the most important cell types in every stage of atherosclerosis. In this review we discuss the principles governing macrophage function in the healthy and infarcted heart. More specifically, how cardiac macrophages participate in myocardial infarction as well as cardiac repair and remodeling. The intricate balance between phenotypically heterogeneous populations of macrophages in the heart have profound and highly orchestrated effects during different phases of myocardial infarction. In the early "inflammatory" stage of MI, resident cardiac macrophages are replaced by classically activated macrophages derived from the bone marrow and spleen. And while the macrophage population shifts towards an alternatively activated phenotype, the inflammatory response subsides giving way to the "reparative/proliferative" phase. Lastly, we describe the therapeutic potential of cardiac macrophages in the context of cell-mediated cardio-protection. Promising results demonstrate innovative concepts; one employing a subset of yolk sac-derived, cardiac macrophages that have complete restorative capacity in the injured myocardium of neonatal mice, and in another example, post-conditioning of cardiac macrophages with cardiosphere-derived cells significantly improved patient's post-MI diagnoses.
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Affiliation(s)
- Jonathan Yap
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA.
| | - Hector A Cabrera-Fuentes
- Tecnologico de Monterrey, Centro de Biotecnologia-FEMSA, Monterrey, NL 264610, Mexico.
- National Heart Research Institute Singapore, National Heart Centre, Singapore 169609, Singapore.
- Cardiovascular and Metabolic Disorders Program, Duke-National University of Singapore Medical School, Singapore 169857, Singapore.
- Institute of Biochemistry, Medical School, Justus-Liebig University, 35392 Giessen, Germany.
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 420008 Kazan, Russia.
| | - Jason Irei
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA.
| | - Derek J Hausenloy
- National Heart Research Institute Singapore, National Heart Centre, Singapore 169609, Singapore.
- Institute of Biochemistry, Medical School, Justus-Liebig University, 35392 Giessen, Germany.
- Yong Loo Lin School of Medicine, National University Singapore, Singapore 117597, Singapore.
- The Hatter Cardiovascular Institute, University College London, London WC1E 6HX, UK.
- The National Institute of Health Research University College London Hospitals Biomedical Research Centre, Research & Development, London W1T 7DN, UK.
| | - William A Boisvert
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96813, USA.
- Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, 420008 Kazan, Russia.
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Muñoz-Vega M, Massó F, Páez A, Vargas-Alarcón G, Coral-Vázquez R, Mas-Oliva J, Carreón-Torres E, Pérez-Méndez Ó. HDL-Mediated Lipid Influx to Endothelial Cells Contributes to Regulating Intercellular Adhesion Molecule (ICAM)-1 Expression and eNOS Phosphorylation. Int J Mol Sci 2018; 19:ijms19113394. [PMID: 30380707 PMCID: PMC6274843 DOI: 10.3390/ijms19113394] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/18/2018] [Accepted: 10/26/2018] [Indexed: 01/19/2023] Open
Abstract
Reverse cholesterol transport (RCT) is considered as the most important antiatherogenic role of high-density lipoproteins (HDL), but interventions based on RCT have failed to reduce the risk of coronary heart disease. In contrast to RCT, important evidence suggests that HDL deliver lipids to peripheral cells. Therefore, in this paper, we investigated whether HDL could improve endothelial function by delivering lipids to the cells. Internalization kinetics using cholesterol and apolipoprotein (apo) AI fluorescent double-labeled reconstituted HDL (rHDL), and human dermal microvascular endothelial cells-1 (HMEC-1) showed a fast cholesterol influx (10 min) and a slower HDL protein internalization as determined by confocal microscopy and flow cytometry. Sphingomyelin kinetics overlapped that of apo AI, indicating that only cholesterol became dissociated from rHDL during internalization. rHDL apo AI internalization was scavenger receptor class B type I (SR-BI)-dependent, whereas HDL cholesterol influx was independent of SR-BI and was not completely inhibited by the presence of low-density lipoproteins (LDL). HDL sphingomyelin was fundamental for intercellular adhesion molecule-1 (ICAM-1) downregulation in HMEC-1. However, vascular cell adhesion protein-1 (VCAM-1) was not inhibited by rHDL, suggesting that components such as apolipoproteins other than apo AI participate in HDL's regulation of this adhesion molecule. rHDL also induced endothelial nitric oxide synthase eNOS S1177 phosphorylation in HMEC-1 but only when the particle contained sphingomyelin. In conclusion, the internalization of HDL implies the dissociation of lipoprotein components and a SR-BI-independent fast delivery of cholesterol to endothelial cells. HDL internalization had functional implications that were mainly dependent on sphingomyelin. These results suggest a new role of HDL as lipid vectors to the cells, which could be congruent with the antiatherogenic properties of these lipoproteins.
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Affiliation(s)
- Mónica Muñoz-Vega
- Molecular Biology Department, Instituto Nacional de Cardiología "Ignacio Chávez", 14080 Mexico City, Mexico.
| | - Felipe Massó
- Physiology Departments, Instituto Nacional de Cardiología "Ignacio Chávez", 14080 Mexico City, Mexico.
| | - Araceli Páez
- Physiology Departments, Instituto Nacional de Cardiología "Ignacio Chávez", 14080 Mexico City, Mexico.
| | - Gilberto Vargas-Alarcón
- Molecular Biology Department, Instituto Nacional de Cardiología "Ignacio Chávez", 14080 Mexico City, Mexico.
| | - Ramón Coral-Vázquez
- Graduate School and Research Division, Escuela Superior de Medicina, Instituto Politécnico Nacional, 11340 México City, Mexico.
- Sub-Directorate of Research and Education, Centro Médico Nacional "20 de Noviembre", Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, 03100 México City, Mexico.
| | - Jaime Mas-Oliva
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Mexico City, Mexico.
| | - Elizabeth Carreón-Torres
- Molecular Biology Department, Instituto Nacional de Cardiología "Ignacio Chávez", 14080 Mexico City, Mexico.
| | - Óscar Pérez-Méndez
- Molecular Biology Department, Instituto Nacional de Cardiología "Ignacio Chávez", 14080 Mexico City, Mexico.
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