scholarly journals Novel 5′ Exon of Scavenger Receptor CD36 Is Expressed in Cultured Human Vascular Smooth Muscle Cells and Atherosclerotic Plaques

2002 ◽  
Vol 22 (3) ◽  
pp. 412-417 ◽  
Author(s):  
Jean-Marc Zingg ◽  
Roberta Ricciarelli ◽  
Enzo Andorno ◽  
Angelo Azzi
2020 ◽  
Author(s):  
Yi Yan ◽  
Ting Li ◽  
Zhonghao Li ◽  
Mingyuan He ◽  
Dejiang Wang ◽  
...  

Abstract Background: Our previous work revealed that augmented AMPK activation inhibit cell migration by phosphorylating its substrate Pdlim5. As medial VSMCs contribute to the major composition of atherosclerotic plaques, a hypothesis is raised that modulation of AMPK-Pdlim5 signal pathway could retard the development of atherosclerosis through inhibiting migration of VSMCs. Therefore, we initiate the present study to investigate whether AMPK agonist like metformin is beneficial for suppressing diabetes-accelerated atherosclerosis in a diabetic mouse model induced by streptozotocin and high fat diet.Methods: For cell experiment, vascular smooth muscle cells (VSMCs) were overexpressed flag fused Pdlim5 and Pdlim5 mutant. Then the engineered VSMCs were introduced with metformin or control drug before determination of phosphorylated Pdlim5 with immunoblotting. For animal work, 8-week-old male ApoE−/−mice were induced diabetes with streptozotocin and then were randomly divided into 8 groups: control group, metformin hydrochloride (300 mg/kg/day) group, wildtype-Pdlim5 (Pdlim5 WT) carried adenovirus (Ad) group, Ad Pdlim5 WT and Met group, Ad Pdlim5 S177A group, Ad Pdlim5 S177A and Met group, Ad Pdlim5 S177D group, Ad Pdlim5 S177D and Met group. All mice were fed with high fat diet after virus infection. At the end, mice were sacrificed to observe atherosclerotic plaques and deposition of VSMCs in plaques. Moreover, 12–15-week-old Myh11-cre-EGFP male mice were accepted ligation of the left carotid artery and randomly divided into control and metformin treatment group. Finally, the injured vessel of Myh11-cre-EGFP mice were isolated to analyze the relationship between AMPK activation and neointima formation.Results: It was found that AMPK directly phosphorylate Pdlim5 at Ser177 in vitro, and metformin, an AMPK agonist, could induce phosphorylation of Pdlim5 indirectly and inhibition of cell migration as a result. Exogenous expression of phosphomimetic S177D-Pdlim5 inhibits lamellipodia formation and migration in VSMCs. It was also demonstrated that VSMCs contribute to the major composition of injury-induced neointimal lesions, while metformin could alleviate the occlusion of carotid artery in a wire-injury mice model. In order to investigate the function of AMPK-Pdlim5 pathway in the context of pathological condition, ApoE−/− male mice were divided randomly into control, streptozocin and high fat diet-induced diabetes mellitus, STZ + HFD together with metformin or Pdlim5 mutant carried adenovirus treatment groups. The results showed increased plasma lipids and aggravated vascular smooth muscle cells infiltration into the atherosclerotic lesion in diabetic mice compared with control mice. However, metformin alleviated diabetes-induced metabolic disorders and atherosclerosis, as well as decreased VSMCs infiltration in atherosclerotic plaques, while Pdlim5 phospho-abolished mutant carried adenovirus S177A-Pdlim5 undermine this protective function.Conclusions: The activation of AMPK-Pdlim5 pathway by chemicals like Metformin could inhibit formation of migratory machine of VSMCs and alleviate the progress of atherosclerotic plaques in diabetic mice. The maintenance of AMPK activity is beneficial for suppressing diabetes-accelerated atherosclerosis or metabolic syndrome.


2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Khatuna Gabunia ◽  
Stephen P Ellison ◽  
James M Richards ◽  
Sheri E Kelemen ◽  
Michael V Autieri

IL-19 is a recently described, putative anti-inflammatory cytokine which had previously been ascribed to be leukocyte specific. IL-19 is not detected in normal artery, but we detected IL-19 in multiple cell types in human atherosclerotic plaque suggesting a role for this interleukin in atherosclerosis. The purpose of this study was to determine whether administration of exogenous IL-19 could attenuate development of pre-formed atherosclerotic plaque, and to identify potential molecular mechanisms. LDLR-/- mice were fed high-fat diet for 12 weeks and then administered with 10ng/g/day IL-19 or PBS for an additional 8 weeks. En face analysis demonstrated that IL-19 could halt, but not reverse existing plaque (26.7+/-1.7%, 41.03+/-3.1%, 23.70+/-2.6% for baseline, PBS control, and IL-19-treated mice). Foam cell formation by macrophages and vascular smooth muscle cells (VSMC) is a hallmark event during atherosclerosis. Nothing has been reported regarding IL-19 effects on macrophage or VSMC lipid uptake; we therefore investigated whether IL-19 affects macrophage and VSMC cholesterol handling. Addition of IL-19 to wild-type bone marrow derived macrophages (BMDM) significantly promoted oxLDL uptake, conversely, BMDM from IL-19-/- mice had significantly less oxLDL uptake compared to wild-type BMDM. Addition of IL-19 to wild type BMDM significantly increased expression of scavenger receptor B1 (SR-B1), and decreased expression of inflammatory cytokines TNFα, IL-12b, MCP1. Interestingly, converse results were obtained with VSMC, as addition of IL-19 to wild-type VSMC decreased uptake of oxLDL ( p<0.05 ) and decreased expression of scavenger receptor CD36. VSMC isolated from IL-19-/- mice had increased uptake of oxLDL (p<0.0001). It is reported that M2 macrophages participate in plaque regression. IL-19 decreased IL-12b and significantly promoted the polarization of anti-inflammatory M2 phenotype in BMDM as evidenced by the increased expression of YM1 and IL-10 mRNA. These data demonstrate that IL-19 can inhibit progression of existing atherosclerotic plaque by modulating lipid metabolism in VSMC and macrophages and by promoting macrophage differentiation into an alternative, anti-inflammatory M2 phenotype.


Author(s):  
Л.А. Богданов ◽  
Е.А. Великанова ◽  
Д.К. Шишкова ◽  
А.Р. Шабаев ◽  
А.Г. Кутихин

Цель исследования - изучение распространенности и локализации сосудистых гладкомышечных клеток (СГМК) различного фенотипа в составе атеросклеротических бляшек сонной артерии, а также взаимосвязи различных клеточных популяций неоинтимы с экспрессией матриксных металлопротеиназ (ММП)-2 и ММП-9 в зависимости от степени стабильности бляшки. Методы. Проведено иммуногистохимическое исследование 16 атеросклеротических бляшек (8 клинически нестабильных и 8 стабильных), полученных при каротидной эндартерэктом в связи с гемодинамически значимым стенозом. Оценка сократительной способности СГМК проводилась при использовании метода иммуногистохимического типирования альфа-актина гладких мышц (α-SMA), синтетического, макрофагального и остеогенного фенотипов СГМК посредством типирования виметина, СВ68 и RUNX2 соответственно. Активность ремоделирования определялась посредством выявления ММП-2 и ММП-9. Результаты. Показано, что около трети каротидных бляшек характеризовались высокой экспрессией MMП-9 CD68-положительными клетками, что не коррелировало с их нестабильностью. Локализация, содержание и соотношение СГМК различного фенотипа и макрофагов значительно варьировали в зависимости от бляшки. Общей закономерностью было преимущественное послойное типирование на α-SMA в зоне интактных эластических волокон медии и, реже, в фиброзной покрышке или прилегающих участках. CD68-положительные клетки визуализировались в толще неоинтимы; некоторая их доля была колокализована с α-SMA, отражая СГМК макрофагального фенотипа. Положительное реакция на виментин наблюдалась на границе с эластическими волокнами медии, либо с основной клеточной массой неоинтимы и характеризовалась прилегающим бесклеточным экстрацеллюлярным матриксом, что свидетельствовало об активном синтезе его соответствующими клетками. Также в неоинтиме обнаруживались клетки положительные как на RUNX2 и α-SMA, так и исключительно RUNX2-положительные клетки. Заключение. Каротидные атеросклеротические бляшки характеризуются различной локализацией, содержанием и соотношением СГМК сократительного, синтетического, макрофагального и остеогенного фенотипов, при этом экспрессия ММП-2 и ММП-9 была ограничена CD68-положительными макрофагами и СГМК макрофагального фенотипа. Aim.To study prevalence and localization of different phenotypes of vascular smooth muscle cells (VSMCs) in carotid atherosclerotic plaques and to examine expression of matrix metalloproteinase (MMP)-2 and MMP-9 in relation to different cell populations within the neointima. Methods. The immunohistochemical examination was performed on 16 atherosclerotic plaques (8 unstable and 8 stable) excised during carotid endarterectomy for critical stenosis. VSMCs of contractile, synthetic, macrophagic, and osteogenic phenotypes were identified by staining for α-smooth muscle actin (α-SMA), vimentin, CD68, and RUNX2, respectively. Activity of neointimal remodeling was assessed by staining for MMP-2 and MMP-9. Results. Approximately one-third of atherosclerotic plaques was positively stained for MMP-9 exclusively expressed in CD68-positive cells, which however, did not correlate with plaque ruptures. Localization, content, and ratio of different VSCM phenotypes significantly varied in different plaques. Positive α-SMA staining was found mainly in the intact media and fibrous cap. In contrast, both CD68-positive and CD68/α-SMA double-positive cells were detected within the neointima but not in the media. Vimentin was expressed in the neointima between the medial layers and fibrous cap near the acellular extracellular matrix suggesting its active production by mesenchymal cells. Both RUNX2- and RUNX2 α-SMA double-positive cells indicative of VSMC osteogenic differentiation were also observed in the neointima. Conclusion. Carotid atherosclerotic plaques contained VSMCs of all phenotypes, which were differentially localized within the neointima; however, the MMP-2 and MMP-9 expression was restricted to CD68-positive macrophages and CD68/α-SMA-positive VSMCs of the macrophagal phenotype.


FEBS Letters ◽  
1999 ◽  
Vol 459 (3) ◽  
pp. 363-366 ◽  
Author(s):  
Koji Murao ◽  
Hitomi Imachi ◽  
Yoshitaka Sayo ◽  
Hitoshi Hosokawa ◽  
Makoto Sato ◽  
...  

Stroke ◽  
2006 ◽  
Vol 37 (8) ◽  
pp. 2044-2053 ◽  
Author(s):  
Begoña Muñoz-García ◽  
Jose Luis Martín-Ventura ◽  
Elena Martínez ◽  
Santiago Sánchez ◽  
Gonzalo Hernández ◽  
...  

Blood ◽  
1997 ◽  
Vol 89 (12) ◽  
pp. 4378-4384 ◽  
Author(s):  
Paul D. Flynn ◽  
Christopher D. Byrne ◽  
Trevor P. Baglin ◽  
Peter L. Weissberg ◽  
Martin R. Bennett

AbstractThrombin activation requires assembly of a prothrombinase complex of activated coagulation factors on an anionic phospholipid surface, classically provided by activated platelets. We have previously shown that anionic phosphatidylserine is exposed by rat vascular smooth muscle cells (VSMCs) undergoing apoptosis after serum withdrawal. In this study, using a chromogenic assay, we have shown thrombin generation by apoptotic VSMCs expressing c-myc (VSMC-myc) with an area under the thrombin-generation curve (AUC) of 305 ± 17 nmol⋅min/L and a peak thrombin (PT) of 154 ± 9 nmol/L. The thrombin-generating potential of the apoptotic VSMC-myc cells was greater than that of unactivated platelets (P = .003 for AUC; P = .0002 for PT) and similar to calcium-ionophore activated platelets (AUC of 332 ± 15 nmol⋅min/L, P = .3; PT of 172 ± 8 nmol/L, P = .2). Thrombin activation was also seen with apoptotic human VSMCs (AUC of 211 ± 8 nmol⋅min/L; PT of 103 ± 4 nmol/L) and was inhibited by annexin V (P < .0001 for AUC and PT). VSMC-myc cells maintained in serum generated less thrombin than after serum withdrawal (P = .0002 for AUC and PT). VSMCs derived from human coronary atherosclerotic plaques that apoptose even in serum also generated thrombin (AUC of 260 ± 2 nmol⋅min/L; PT of 128 ± 4 nmol/L). We conclude that apoptotic VSMCs possess a significant thrombin-generating capacity secondary to phosphatidylserine exposure. Apoptotic cells within atherosclerotic plaques may allow local thrombin activation, thereby contributing to disease progression.


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