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1.
Life Sci ; 264: 118721, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33160993

RESUMO

BACKGROUND: Gypenoside (GP) is the major bioactive constituent of G. pentaphyllum, a traditional Chinese medicine. It has been reported that GP can affect autophagy and lipid metabolism in cultured cells. We hypothesize that GP can inhibit foam cell formation in cultured macrophages through autophagy modulation. METHODS: THP1 cells were cultured and treated with oxidized low-density lipoprotein (ox-LDL), followed by GP treatment at different concentrations. The autophagy flux was evaluated using western blot and confocal microscope analyses. The ox-LDL uptake and foam cell formation abilities were measured. RESULTS: We found that ox-LDL impaired the autophagy flux in the cultured macrophages, indicated by a significant reduction of LC3-II and autophagosome puncta quantification, as well as an accumulation of p62 proteins. GP treatment, however, dose-dependently restored the autophagy flux impaired by ox-LDL and reduced the ox-LDL uptake and foam cell transformation from THP1 cells, which can be alleviated, or exacerbated, by modulation of autophagy status using autophagy enhancer or inhibitor. Coimmunoprecipitation assays showed that GP up-regulated Srit1 and FOXO1 expression and enhanced their direct interaction, and thus contributed to the regulation of autophagy. CONCLUSION: GP inhibits ox-LDL uptake and foam cell formation through enhancing Sirt1-FOXO1 mediated autophagy flux restoration, suggesting this compound has therapeutic potential for atherosclerosis.


Assuntos
Autofagia , Células Espumosas/metabolismo , Proteína Forkhead Box O1/metabolismo , Lipoproteínas LDL/metabolismo , Sirtuína 1/metabolismo , Autofagia/efeitos dos fármacos , Células Espumosas/efeitos dos fármacos , Proteína Forkhead Box O1/genética , Gynostemma , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Extratos Vegetais/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sirtuína 1/genética , Células THP-1 , Regulação para Cima/efeitos dos fármacos
2.
JAMA Netw Open ; 3(11): e2025466, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33211107

RESUMO

Importance: Higher Mediterranean diet (MED) intake has been associated with reduced risk of type 2 diabetes, but underlying biological mechanisms are unclear. Objective: To characterize the relative contribution of conventional and novel biomarkers in MED-associated type 2 diabetes risk reduction in a US population. Design, Setting, and Participants: This cohort study was conducted among 25 317 apparently healthy women. The participants with missing information regarding all traditional and novel metabolic biomarkers or those with baseline diabetes were excluded. Participants were invited for baseline assessment between September 1992 and May 1995. Data were collected from November 1992 to December 2017 and analyzed from December 2018 to December 2019. Exposures: MED intake score (range, 0 to 9) was computed from self-reported dietary intake, representing adherence to Mediterranean diet intake. Main Outcomes and Measures: Incident cases of type 2 diabetes, identified through annual questionnaires; reported cases were confirmed by either telephone interview or supplemental questionnaire. Proportion of reduced risk of type 2 diabetes explained by clinical risk factors and a panel of 40 biomarkers that represent different physiological pathways was estimated. Results: The mean (SD) age of the 25 317 female participants was 52.9 (9.9) years, and they were followed up for a mean (SD) of 19.8 (5.8) years. Higher baseline MED intake (score ≥6 vs ≤3) was associated with as much as a 30% lower type 2 diabetes risk (age-adjusted and energy-adjusted hazard ratio, 0.70; 95% CI, 0.62-0.79; when regression models were additionally adjusted with body mass index [BMI]: hazard ratio, 0.85; 95% CI, 0.76-0.96). Biomarkers of insulin resistance made the largest contribution to lower risk (accounting for 65.5% of the MED-type 2 diabetes association), followed by BMI (55.5%), high-density lipoprotein measures (53.0%), and inflammation (52.5%), with lesser contributions from branched-chain amino acids (34.5%), very low-density lipoprotein measures (32.0%), low-density lipoprotein measures (31.0%), blood pressure (29.0%), and apolipoproteins (23.5%), and minimal contribution (≤2%) from hemoglobin A1c. In post hoc subgroup analyses, the inverse association of MED diet with type 2 diabetes was seen only among women who had BMI of at least 25 at baseline but not those who had BMI of less than 25 (eg, women with BMI <25, age- and energy-adjusted HR for MED score ≥6 vs ≤3, 1.01; 95% CI, 0.77-1.33; P for trend = .92; women with BMI ≥25: HR, 0.76; 95% CI, 0.67-0.87; P for trend < .001). Conclusions and Relevance: In this cohort study, higher MED intake scores were associated with a 30% relative risk reduction in type 2 diabetes during a 20-year period, which could be explained in large part by biomarkers of insulin resistance, BMI, lipoprotein metabolism, and inflammation.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Dieta Mediterrânea/estatística & dados numéricos , Adiposidade , Adulto , Aminoácidos de Cadeia Ramificada/metabolismo , Apolipoproteína A-I/metabolismo , Apolipoproteína B-100/metabolismo , Apolipoproteínas/metabolismo , Índice de Massa Corporal , Proteína C-Reativa/metabolismo , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Dieta/estatística & dados numéricos , Feminino , Hemoglobina A Glicada/metabolismo , Humanos , Inflamação/metabolismo , Resistência à Insulina , Molécula 1 de Adesão Intercelular/metabolismo , Lipoproteína(a)/metabolismo , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/metabolismo , Lipoproteínas VLDL/metabolismo , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Proteção , Espectroscopia de Prótons por Ressonância Magnética , Triglicerídeos/metabolismo
3.
Toxicol Appl Pharmacol ; 409: 115295, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33096109

RESUMO

Atherosclerosis (AS), a common arterial disease, is one of the main pathological roots of cardiovascular disease. The formation and accumulation of foam cells is an important event in early AS. An imbalance between cholesterol uptake and efflux is the primary cause of foam cell formation. Although research has focused on preventing the formation of foam cells, a safe and effective therapy has to be found. Zafirlukast is a widely useful type 1 cysteinyl leukotriene receptor (CysLT1R) antagonist with a good safety profile. Zafirlukast is the most used for the treatment of asthma and allergic rhinitis. However, the effect of zafirlukast on preventing the formation of foam cells has not been determined. The aim of this study was to investigate whether zafirlukast prevented macrophages from transforming into foam cells. Our data show that zafirlukast reduced the expression of CD36 and lipoprotein receptor-1 (LOX-1), which are responsible for lipid uptake. In addition, zafirlukast enhanced the activity of ATP-Binding Cassette A1 (ABCA1) and ATP-binding cassette transporter G1 (ABCG1), leading to the acceleration of cholesterol efflux. Furthermore, zafirlukast influenced the activity of the phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathway, which mediates the expression of ABCA1 and ABCG1. In summary, our data indicate that zafirlukast might be a potential treatment strategy for AS by mediating lipid metabolism and preventing the formation of foam cells.


Assuntos
Células Espumosas/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Compostos de Tosil/farmacologia , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Células Espumosas/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
4.
PLoS One ; 15(10): e0240659, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33057430

RESUMO

SR-BI binds various lipoproteins, including HDL, LDL as well as VLDL, and mediates selective cholesteryl ester (CE) uptake. HDL derived CE accumulates in cellular lipid droplets (LDs), which also store triacylglycerol (TAG). We hypothesized that SR-BI could significantly facilitate LD formation, in part, by directly transporting LDL derived neutral lipids (NL) such as CE and TAG into LDs without lipolysis and de novo lipid synthesis. SR-BI overexpression greatly increased LDL uptake and LD formation in stably transfected HeLa cells (SR-BI-HeLa). LDs isolated from SR-BI-HeLa contained 4- and 7-times more CE and TAG, respectively, than mock-transfected HeLa (Mock-HeLa). In contrast, LDL receptor overexpression in HeLa (LDLr-HeLa) greatly increased LDL uptake, degradation with moderate 1.5- and 2-fold increases of CE and TAG, respectively. Utilizing CE and TAG analogs, BODIPY-TAG (BP-TAG) and BODIPY-CE (BP-CE), for tracking LDL NL, we found that after initial binding of LDL to SR-BI-HeLa, apoB remained at the cell surface, while BP-CE and BP-TAG were sorted and simultaneously transported together to LDs. Both lipids demonstrated limited internalization to lysosomes or endoplasmic reticulum in SR-BI-HeLa. In LDLr-HeLa, NLs demonstrated clear lysosomal sequestration without their sorting to LDs. An inhibition of TAG and CE de novo synthesis by 90-95% only reduced TAG and CE LD content by 45-50%, and had little effect on BP-CE and BP-TAG transport to LDs in SR-BI HeLa. Furthermore, intravenous infusion of 1-2 mg of LDL increased liver LDs in normal (WT) but not in SR-BI KO mice. Mice transgenic for human SR-BI demonstrated higher liver LD accumulation than WT mice. Finally, Electro Spray Infusion Mass Spectrometry (ESI-MS) using deuterated d-CE found that LDs accumulated up to 40% of unmodified d-CE LDL. We conclude that SR-BI mediates LDL-induced LD formation in vitro and in vivo. In addition to cytosolic NL hydrolysis and de novo lipid synthesis, this process includes selective sorting and transport of LDL NL to LDs with limited lysosomal NL sequestration and the transport of LDL CE, and TAG directly to LDs independently of de novo synthesis.


Assuntos
Gotículas Lipídicas/metabolismo , Lipídeos/química , Lipoproteínas LDL/metabolismo , Receptores Depuradores Classe B/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Compostos de Boro/metabolismo , Ésteres do Colesterol/metabolismo , Coenzima A Ligases/antagonistas & inibidores , Coenzima A Ligases/metabolismo , Inibidores Enzimáticos/farmacologia , Células HeLa , Humanos , Gotículas Lipídicas/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de LDL/metabolismo , Triazenos/farmacologia , Triglicerídeos/metabolismo
5.
Gen Physiol Biophys ; 39(5): 437-448, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33084597

RESUMO

Macrophages conversion to foam cells strongly promoted atherosclerosis progression by plaque formation and plaque rupture. Macrophages swallow oxidized-low density lipoprotein (ox-LDL) to promote foam cell formation. Protease-activated receptor 2 (PAR2) has been reported to take part in atherosclerotic development. However, the effects of PAR2 in macrophages were rarely investigated. In this study, human monocyte, THP-1 was induced to macrophages by using phorbol 12-myristate 13-acetate (PMA). Subsequently, an in vitro model was arranged by using ox-LDL to treat the macrophages. The data showed that inhibition of PAR2 reduced ox-LDL-induced foam cell formation, inflammation, and apoptosis. Additionally, ox-LDL increased PAR2 and inhibited Dickkopf-related protein 1 (DKK1) expression, which is a Wnt signaling inhibitor. PAR2 knocked-down decreased DKK1 and enhanced expression of Wnt3a, ß-catenin. Meanwhile, DKK1 overexpression reversed the effects of PAR2 on foam cell formation, inflammation, and apoptosis. In summary, PAR2 is essential for the formation of foam cells, inflammation, and apoptosis in macrophages which plays a critical role during atherosclerosis. PAR2 plays roles in macrophages treated with ox-LDL via DKK1/Wnt/ß-catenin signaling.


Assuntos
Apoptose , Inflamação , Lipoproteínas LDL/metabolismo , Receptor PAR-2 , Via de Sinalização Wnt , Inativação Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Receptor PAR-2/genética , Células THP-1 , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo
6.
Int Heart J ; 61(5): 1034-1040, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32999190

RESUMO

Low-density lipoprotein (LDL) particles are known to be atherogenic agents in coronary artery diseases. They adjust to other electronegative forms and can be the subject for the enhancement of inflammatory events in vessel subendothelial spaces. The LDL uptake is related to the membrane scavenger receptors, including LDL receptor (LDLR). The LDLR expression is closely associated with LDL uptake and occurrence of diseases, such as atherosclerotic cardiovascular diseases. Our findings identified USP16 as a novel regulator of LDLR due to its ability to prevent ubiquitylation-dependent LDLR degradation, further promoting the uptake of LDL. The enhancement of USP16-mediated deubiquitination andthe suppressive degradation of the LDLR cause the presentation of a potential strategy to increase LDL cholesterol clearance.


Assuntos
Receptores de LDL/metabolismo , Ubiquitina Tiolesterase/metabolismo , Ubiquitinação , Células HeLa , Humanos , Lipoproteínas LDL/metabolismo , Processamento de Proteína Pós-Traducional
7.
Nat Commun ; 11(1): 5426, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33110060

RESUMO

Novel atherosclerosis models are needed to guide clinical therapy. Here, we report an in vitro model of early atherosclerosis by fabricating and perfusing multi-layer arteriole-scale human tissue-engineered blood vessels (TEBVs) by plastic compression. TEBVs maintain mechanical strength, vasoactivity, and nitric oxide (NO) production for at least 4 weeks. Perfusion of TEBVs at a physiological shear stress with enzyme-modified low-density-lipoprotein (eLDL) with or without TNFα promotes monocyte accumulation, reduces vasoactivity, alters NO production, which leads to endothelial cell activation, monocyte accumulation, foam cell formation and expression of pro-inflammatory cytokines. Removing eLDL leads to recovery of vasoactivity, but not loss of foam cells or recovery of permeability, while pretreatment with lovastatin or the P2Y11 inhibitor NF157 reduces monocyte accumulation and blocks foam cell formation. Perfusion with blood leads to increased monocyte adhesion. This atherosclerosis model can identify the role of drugs on specific vascular functions that cannot be assessed in vivo.


Assuntos
Arteríolas/fisiopatologia , Aterosclerose/fisiopatologia , Arteríolas/química , Arteríolas/citologia , Aterosclerose/genética , Aterosclerose/metabolismo , Fenômenos Biomecânicos , Adesão Celular , Proliferação de Células , Células Cultivadas , Células Espumosas/citologia , Células Espumosas/metabolismo , Humanos , Lipoproteínas LDL/metabolismo , Modelos Biológicos , Monócitos/citologia , Monócitos/metabolismo , Óxido Nítrico/metabolismo , Engenharia Tecidual , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
8.
Arch Biochem Biophys ; 694: 108589, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-33010229

RESUMO

There is ample evidence in the epidemiological literature that polyphenols, the major non-vitamin antioxidants in plant foods and beverages, have a beneficial effect on heart disease. Until recently other mechanisms which polyphenols exhibit such as cell signaling and regulating nitric oxide bioavailability have been investigated. The oxidation theory of atherosclerosis implicates LDL oxidation as the beginning step in this process. Nine polyphenols from eight different classes and several of their O-methylether, O-glucuronide and O-sulfate metabolites have been shown in this study to bind to the lipoproteins and protect them from oxidation at lysosomal/inflammatory pH (5.2), and physiological pH (7.4). Polyphenols bind to the apoprotein at pH 7.4 with Kb > 106 M-1 and the number of molecules of polyphenols bound per LDL particle under saturation conditions varied from 0.4 for ferulic acid to 13.1 for quercetin. Competition studies between serum albumin and LDL show that substantial lipoprotein binding occurs even in the presence of a great molar excess of albumin, the major blood protein. These in vitro results are borne out by published human supplementation studies showing that polyphenol metabolites from red wine, olive oil and coffee are found in LDL even after an overnight fast. A single human supplementation with various fruit juices, coffee and tea also produced an ex vivo protection against lipoprotein oxidation under postprandial conditions. This in vivo binding is heart-protective based on published olive oil consumption studies. Relevant to heart disease, we hypothesize that the binding of polyphenols and metabolites to LDL functions as a transport mechanism to carry these antioxidants to the arterial intima, and into endothelial cells and macrophages. Extracellular and intracellular polyphenols and their metabolites are heart-protective by many mechanisms and can also function as potent "intraparticle" and intracellular antioxidants due to their localized concentrations that can reach as high as the micromolar level. Low plasma concentrations make polyphenols and their metabolites poor plasma antioxidants but their concentration in particles such as lipoproteins and cells is high enough for polyphenols to provide cardiovascular protection by direct antioxidant effects and by other mechanisms such as cell signaling.


Assuntos
Antioxidantes/farmacologia , Cardiotônicos/farmacologia , Lipoproteínas LDL/metabolismo , Polifenóis/farmacologia , Animais , Antioxidantes/metabolismo , Cardiotônicos/metabolismo , Humanos , Lipoproteínas LDL/química , Oxirredução/efeitos dos fármacos , Polifenóis/metabolismo , Ligação Proteica , Albumina Sérica Humana/metabolismo , Suínos
9.
Nutr Metab Cardiovasc Dis ; 30(12): 2406-2416, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-32917500

RESUMO

BACKGROUND AND AIM: Abnormal aggregation of oxidized low-density lipoprotein (Ox-LDL) in vascular endothelial cells (VECs) is one of the major pathological changes in atherosclerotic lesions. Our research aimed to assess the mechanism of humanin (HN) in promoting autophagic degradation of Ox-LDL in HUVECs. METHODS AND RESULTS: Flow cytometry and lipid quantitation results showed that Ox-LDL caused lipid and cholesterol accumulation in HUVECs. Western blot results showed that Ox-LDL increased the expression of autophagy-related proteins P62 and LC3-II in a concentration-dependent manner. The cathepsin D activity assay showed that Ox-LDL inhibited the function of cathepsin D. HNG pretreatment reduced lipid and cholesterol aggregation in HUVECs induced by Ox-LDL, increased LC3-II protein level, decreased P62 protein content, and reversed Ox-LDL-induced cathepsin D functional impairment. Inhibition of the FPRL1 pathway by FPRL1 siRNA or the FPRL1-specific inhibitor Boc-MLF blocked all HNG's protective effects. These results indicate that HNG could restore cathepsin D activity and protein level in HUVECs to repair lysosomal functional damage induced by Ox-LDL, further repairing Ox-LDL-induced autophagic damage in HUVECs. CONCLUSION: HNG restores the activity of Ox-LDL-induced damaged lysosomal enzyme cathepsin D through its membrane protein receptor FPRL1 to promote autophagic degradation of Ox-LDL in HUVECs.


Assuntos
Autofagia/efeitos dos fármacos , Catepsina D/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Lisossomos/efeitos dos fármacos , Peptídeos/farmacologia , Receptores de Formil Peptídeo/metabolismo , Receptores de Lipoxinas/metabolismo , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/enzimologia , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Lisossomos/enzimologia , Lisossomos/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Proteólise , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais
10.
Curr Atheroscler Rep ; 22(10): 59, 2020 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-32772254

RESUMO

PURPOSE OF REVIEW: Atherosclerosis is a chronic disease characterized by lipid retention and inflammation in the artery wall. The retention and oxidation of low-density lipoprotein (LDL) in sub-endothelial space play a critical role in atherosclerotic plaque formation and destabilization. Oxidized LDL (ox-LDL) and other modified LDL particles are avidly taken up by endothelial cells, smooth muscle cells, and macrophages mainly through several scavenger receptors, including CD36 which is a class B scavenger receptor and membrane glycoprotein. RECENT FINDINGS: Animal studies performed on CD36-deficient mice suggest that deficiency of CD36 prevents the development of atherosclerosis, though with some debate. CD36 serves as a signaling hub protein at the crossroad of inflammation, lipid metabolism, and fatty acid metabolism. In addition, the level of soluble CD36 (unattached to cells) in the circulating blood was elevated in patients with atherosclerosis and other metabolic disorders. We performed a state-of-the-art review on the structure, ligands, functions, and regulation of CD36 in the context of atherosclerosis by focusing on the pathological role of CD36 in the dysfunction of endothelial cells, smooth muscle cells, monocytes/macrophages, and platelets. Finally, we highlight therapeutic possibilities to target CD36 expression/activity in atherosclerosis.


Assuntos
Aterosclerose/metabolismo , Antígenos CD36/química , Antígenos CD36/metabolismo , Placa Aterosclerótica/metabolismo , Animais , Aterosclerose/tratamento farmacológico , Antígenos CD36/antagonistas & inibidores , Colesterol/metabolismo , Células Endoteliais/metabolismo , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Camundongos , Miócitos de Músculo Liso/metabolismo , Placa Aterosclerótica/tratamento farmacológico , Ativação Plaquetária , Transdução de Sinais/efeitos dos fármacos
11.
Med Hypotheses ; 144: 110128, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32758903

RESUMO

It has been proposed that a degraded immune system is (one of) the condition(s) that predispose certain subjects to fatal consequences from infection by SARS-CoV-2. It is unknown whether therapeutic regimens to which these patients may have been subjected to in the months/years preceding the infection could be immunocompromising. Statins are among the most widely prescribed cholesterol-lowering drugs. As competitive inhibitors of HMG-CoA-reductase, the key enzyme of the "mevalonate pathway" through which essential compounds, not only cholesterol, are synthesized, statins decrease the levels of cholesterol, and thus LDLs, as an innate defense mechanism, with controversial results in decreasing mortality from cardiovascular disease. Moreover, statins have pleiotropic, mostly deleterious effects on many cell types, including immune cells. In the attempt to decipher the enigma of SARS-CoV-2 infectivology, the hypothesis should be tested whether the population of subjects who succumbed to Covid-19 may have developed a compromised immunity at sub-clinical levels and have become more susceptible to fatal consequences from SARS-Cov-2 infection due to statin therapy.


Assuntos
/tratamento farmacológico , Ácido Mevalônico/química , Oxirredução , Selenoproteínas/química , Colesterol/metabolismo , LDL-Colesterol/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Sistema Imunitário , Imunidade Inata , Inflamação , Lipoproteínas LDL/metabolismo , Modelos Teóricos , Estresse Oxidativo
12.
Am J Physiol Heart Circ Physiol ; 319(4): H835-H846, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795179

RESUMO

Analyses of individual atherosclerotic plaques are mostly descriptive, relying, for example, on histological classification by spectral analysis of ultrasound waves or staining and observing particular cellular components. Such passive methods have proved useful for characterizing the structure and vulnerability of plaques but have little quantitative predictive power. Our aim is to introduce and discuss a computational framework to provide insight to clinicians and help them visualize internal plaque dynamics. We use partial differential equations (PDEs) with macrophages, necrotic cells, oxidized lipids, oxygen concentration, and platelet-derived growth factor (PDGF) as primary variables coupled to a biomechanical model to describe vessel growth. The model is deterministic, providing mechanical, morphological, and histological characteristics of an atherosclerotic vessel at any desired future time point. We use our model to create computer-generated animations of a plaque evolution that are in qualitative agreement with published serial ultrasound images and hypothesize possible atherogenic mechanisms. A systems biology model consisting of five differential equations is able to capture the morphology of necrotic cores residing within vulnerable atherosclerotic plaque. In the context of the model, the distribution of oxidized low-density lipoprotein (Ox-LDL) particles, endothelial inflammation, plaque oxygenation (via the presence of vasa vasora), and intimal oxygenation are four important factors that drive changes in core morphology.NEW & NOTEWORTHY In this article, we propose a quantitative framework to describe the evolution of atherosclerotic plaque. We use partial differential equations (PDEs) with macrophages, necrotic cells, oxidized lipids, oxygen concentration, and PDGF as primary variables coupled to a biomechanical model to describe vessel growth. A feature of our method is that it outputs color-coded vessel sections corresponding to regions of the plaque that are necrotic and fibrous, qualitatively similar to images generated by enhanced intravascular ultrasound.


Assuntos
Artérias/patologia , Aterosclerose/patologia , Simulação por Computador , Modelos Cardiovasculares , Placa Aterosclerótica , Biologia de Sistemas , Animais , Artérias/metabolismo , Aterosclerose/metabolismo , Difusão , Progressão da Doença , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Espumosas/metabolismo , Células Espumosas/patologia , Humanos , Mediadores da Inflamação/metabolismo , Lipoproteínas LDL/metabolismo , Necrose , Oxigênio/metabolismo
13.
Am J Physiol Regul Integr Comp Physiol ; 319(3): R376-R386, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32755464

RESUMO

The present study was conducted to understand key biochemical, physiological, and molecular changes associated with ovarian growth and with lipid transfer and/or accumulation into the ovary during oogenesis in captive beluga sturgeon. Plasma levels of triacylglycerides, cholesterol, phospholipid, and sex steroid hormones were determined and all were found to increase notably throughout development from the perinucleolar to the tertiary yolk stage. Using fast protein liquid chromatography, we recognized three major lipoprotein peaks in chromatograms from all samples. These peaks were characterized as containing very low-density lipoprotein (Vldl), low-density lipoprotein/high-density lipoprotein (Ldl/Hdl), and plasma proteins. While Ldl/Hdl represented the most abundant lipoprotein fraction, the relative abundance of different lipoprotein classes did not change with the stage of oogenesis. Eluted lipoproteins were separated using sodium dodecyl-sulfate polyacrylamide gel electrophoresis and sequenced. The peptide sequence spectra for 66-kDa, 205-kDa, 29-kDa, and 70-kDa bands matched with albumin, vitellogenin (Vtg) AB2b, immunoglobulin light-chain precursor, and immunoglobulin heavy-chain, respectively. The large amount of albumin in the plasma protein peak and the confined presence of Vtg AB2b to within Ldl/Hdl reinforce the lipoprotein classification. Lastly, transcript levels of genes encoding ovarian lipoprotein lipase (lpl), apolipoprotein E (apoe), very low-density lipoprotein receptors (vldlr), and low-density lipoprotein receptor-related protein 8-like (lrp8) were estimated using quantitative RT-PCR. The high mRNA levels of lpl, apoe, and lipoprotein receptors vldlr and lrp8 in previtellogenic females suggest that sturgeon oocytes need to be prepared to accept and traffic Vtg and lipids internally, before the start of vitellogenesis.


Assuntos
Lipase Lipoproteica/metabolismo , Lipoproteínas VLDL/sangue , Ovário/crescimento & desenvolvimento , Triglicerídeos/metabolismo , Animais , Apolipoproteínas E/metabolismo , Colesterol/sangue , Feminino , Lipoproteínas LDL/metabolismo , Ovário/metabolismo
14.
Life Sci ; 259: 118241, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32791147

RESUMO

AIMS: Compelling evidences demonstrate that informative RNAs play essential role in therapy of atherosclerosis. Here, we attempted to study the role of hsa_circ_0000345 (circRSF1) in endothelial cell damage through competing endogenous RNA pathway. MATERIALS AND METHODS: Expression of circRSF1, miRNA-758-3p (miR-758) and cyclin D2 (CCND2) was detected using RT-qPCR and western blotting, and the cross-talk among them was identified using dual-luciferase reporter assay and RNA immunoprecipitation. The low-density lipoprotein cholesterol (LDL-C) level was measured with enzyme-linked immunosorbent assay. Cell growth was measured by MTS assay, flow cytometry and caspase-3 activity assay kit. Migration and tube formation were determined by scratch migration assay and tube formation assay, respectively. KEY FINDINGS: CircRSF1 and CCND2 were downregulated, whereas miR-758 was upregulated in serum of patients with atherosclerosis and oxidized low-density lipoprotein (ox-LDL)-treated human aortic endothelial cells (HAECs). Moreover, levels of circRSF1, miR-758 and CCND2 were correlated with circulating LDL-C level. Restoring circRSF1 and silencing miR-758 could improve cell viability, tube formation and migration of HAECs under ox-LDL treatment, as well as attenuated apoptotic rate and caspase-3 activity. However, miR-758 upregulation counteracted the promotion of circRSF1 on cell growth, migration and tube formation in ox-LDL-induced HAECs; so did CCND2 deletion on effect of miR-758 silence. Notably, circRSF1 and CCND2 could competitively bound to miR-758, and circRSF1 positively regulated CCND2 expression via miR-758. SIGNIFICANCE: CircRSF1 could protect against ox-LDL-induced endothelial cell injury in vitro via miR-758/CCND2 axis, suggesting circRSF1 as a potential target for the treatment of atherosclerosis.


Assuntos
Aterosclerose/sangue , Ciclina D2/metabolismo , MicroRNAs/sangue , Proteínas Nucleares/genética , RNA Circular/sangue , Transativadores/genética , Adulto , Apoptose/efeitos dos fármacos , Aterosclerose/genética , Aterosclerose/patologia , Estudos de Casos e Controles , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclina D2/genética , Células Endoteliais/metabolismo , Feminino , Humanos , Lipoproteínas LDL/sangue , Lipoproteínas LDL/metabolismo , Lipoproteínas LDL/farmacologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , RNA Circular/genética , Transdução de Sinais/efeitos dos fármacos
15.
Life Sci ; 259: 118251, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32795540

RESUMO

AIMS: Circular RNAs (circRNAs) are relevant to atherosclerosis progression. However, the role and mechanism of circRNA hsa_circ_0029589 (circ_0029589) in atherosclerosis are not fully understood. This research aims to explore the function and mechanism of circ_0029589 in oxidized low-density lipoprotein (ox-LDL)-caused vascular smooth muscle cells (VSMCs) injury in vitro. MAIN METHODS: VSMCs were challenged via ox-LDL to mimic atherosclerosis-like injury in vitro. Circ_0029589, microRNA-214-3p (miR-214-3p) and stromal interaction molecule 1 (STIM1) abundances were detected via quantitative reverse transcription polymerase chain reaction or western blot. Cell proliferation was investigated via cell viability, cycle, apoptosis and proliferation-associated protein levels. Cell migration and invasion were assessed via transwell analysis. The relationship between miR-214-3p and circ_0029589 or STIM1 was tested via dual-luciferase reporter analysis and RNA immunoprecipitation. KEY FINDINGS: Circ_0029589 level was enhanced in ox-LDL-challenged VSMCs. Circ_0029589 interference constrained cell proliferation, migration and invasion in ox-LDL-challenged VSMCs. miR-214-3p was targeted by circ_0029589 and miR-214-3p knockdown weakened the suppressive function of circ_0029589 silence on VSMCs proliferation, migration and invasion. STIM1 was targeted via miR-214-3p and miR-214-3p could suppress VSMCs proliferation, migration and invasion via decreasing STIM1. Moreover, circ_0029589 modulated STIM1 level by miR-214-3p. SIGNIFICANCE: Circ_0029589 knockdown repressed proliferation, migration and invasion of VSMCs challenged via ox-LDL by regulating miR-214-3p and STIM1, indicating that circ_0029589 might play important role in atherosclerosis.


Assuntos
Aterosclerose/genética , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , RNA Circular/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Apoptose/fisiologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Progressão da Doença , Humanos , Lipoproteínas LDL/metabolismo , MicroRNAs/genética , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiologia , Invasividade Neoplásica , Proteínas de Neoplasias/genética , RNA Circular/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Molécula 1 de Interação Estromal/genética
16.
Life Sci ; 258: 118030, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32739470

RESUMO

The risk of atherosclerosis (AS) ascends among post-menopausal women, while current hormone replacement therapy exerts several adverse effects. Alisol B 23-acetate (AB23A), a tetracyclic triterpenoid isolated from the rhizome of Alisma orientale, was reported to show multiple physiological activities, including regulating lipid metabolism. According to molecular docking analysis, it was predicted to bind with estrogen receptor α (ERα). In this study, we aimed to observe the effect of AB23A on preventing post-menopausal AS and explore whether the mechanism was mediated by ERα. In vitro, free fatty acid (FFA) was applied to induce the abnormal lipid metabolism of L02 cells. In vivo, the ApoE-/- mice were ovariectomized to mimic the cessation of estrogen. The high-fat diet was also given to induce post-menopausal AS. We demonstrated AB23A attenuated the accumulation of total cholesterol and triglyceride induced by free fatty acids in hepatocytes. In high-fat diet-ovariectomy-treated ApoE-/- mice, AB23A eliminated lipids in blood and liver. AB23A not only reduced the synthesis of proprotein convertase subtilisin/kexin type 9 (PCSK9) through sterol-regulatory element binding proteins (SREBPs) but also suppressed the secretion of PCSK9 through silent information regulator 1 (SIRT1). Notably, AB23A promoted the expression of ERα in vivo and in vitro. The both ERα inhibitor and ERα siRNA were also applied in confirming whether the hepatic protective effect of AB23A was mediated by ERα. We found that AB23A significantly promoted the expression of ERα. AB23A could inhibit the synthesis and secretion of PCSK9 through ERα, lower the accumulation of triglyceride and cholesterol, and prevent post-menopausal AS.


Assuntos
Aterosclerose/patologia , Colestenonas/farmacologia , Receptor alfa de Estrogênio/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Pós-Menopausa/efeitos dos fármacos , Animais , Aterosclerose/genética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colestenonas/química , Dieta Hiperlipídica , Ácidos Graxos/metabolismo , Feminino , Lipoproteínas LDL/metabolismo , Camundongos , Ovariectomia , Regiões Promotoras Genéticas/genética , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Sirtuína 1/metabolismo , Proteínas de Ligação a Elemento Regulador de Esterol/genética , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Regulação para Cima/efeitos dos fármacos
17.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1865(10): 158769, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32712249

RESUMO

Lipoproteins play a central role in the development of atherosclerosis. High and low-density lipoproteins (HDL and LDL), known as 'good' and 'bad' cholesterol, respectively, remove and/or deposit lipids into the artery wall. Hence, insight into lipid exchange processes between lipoproteins and cell membranes is of particular importance in understanding the onset and development of cardiovascular disease. In order to elucidate the impact of phospholipid tail saturation and the presence of cholesterol in cell membranes on these processes, neutron reflection was employed in the present investigation to follow lipid exchange with both HDL and LDL against model membranes. Mirroring clinical risk factors for the development of atherosclerosis, lower exchange was observed in the presence of cholesterol, as well as for an unsaturated phospholipid, compared to faster exchange when using a fully saturated phospholipid. These results highlight the importance of membrane composition on the interaction with lipoproteins, chiefly the saturation level of the lipids and presence of cholesterol, and provide novel insight into factors of importance for build-up and reversibility of atherosclerotic plaque. In addition, the correlation between the results and well-established clinical risk factors suggests that the approach taken can be employed also for understanding a broader set of risk factors including, e.g., effects of triglycerides and oxidative stress, as well as local effects of drugs on atherosclerotic plaque formation.


Assuntos
Aterosclerose/metabolismo , Colesterol/metabolismo , Lipídeos/genética , Lipoproteínas/genética , Aterosclerose/genética , Aterosclerose/patologia , Membrana Celular/genética , Membrana Celular/metabolismo , Colesterol/genética , Gorduras na Dieta , Ácidos Graxos , Humanos , Lipoproteínas/metabolismo , Lipoproteínas HDL/genética , Lipoproteínas HDL/metabolismo , Lipoproteínas LDL/genética , Lipoproteínas LDL/metabolismo , Fosfolipídeos/genética , Fosfolipídeos/metabolismo , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Triglicerídeos/genética , Triglicerídeos/metabolismo
18.
Nutr Metab Cardiovasc Dis ; 30(9): 1590-1599, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32605883

RESUMO

BACKGROUND AND AIMS: Hypercholesterolemia and oxidative stress are two of the most important risk factors for atherosclerosis. The aim of the present work was to evaluate mandarin (Citrus reticulata) peel oil (MPO) in cholesterol metabolism and lipid synthesis, and its antioxidant capacity. METHODS AND RESULTS: Incubation of hepatic HepG2 cells with MPO (15-60 µL/L) reduced cholesterogenesis and saponifiable lipid synthesis, demonstrated by [14C]acetate radioactivity assays. These effects were associated with a decrease in a post-squalene reaction of the mevalonate pathway. Molecular docking analyses were carried out using three different scoring functions to examine the cholesterol-lowering property of all the components of MPO against lanosterol synthase. Docking simulations proposed that minor components of MPO monoterpenes, like alpha-farnesene and neryl acetate, as well the major component, limonene and its metabolites, could be partly responsible for the inhibitory effects observed in culture assays. MPO also decreased RAW 264.7 foam cell lipid storage and its CD36 expression, and prevented low-density lipoprotein (LDL) lipid peroxidation. CONCLUSION: These results may imply a potential role of MPO in preventing atherosclerosis by a mechanism involving inhibition of lipid synthesis and storage and the decrease of LDL lipid peroxidation.


Assuntos
Antioxidantes/farmacologia , Aterosclerose/prevenção & controle , Colesterol/metabolismo , Citrus , Dislipidemias/tratamento farmacológico , Células Espumosas/efeitos dos fármacos , Frutas , Hepatócitos/efeitos dos fármacos , Hipolipemiantes/farmacologia , Lipoproteínas LDL/metabolismo , Óleos Vegetais/farmacologia , Animais , Antioxidantes/isolamento & purificação , Aterosclerose/etiologia , Aterosclerose/metabolismo , Antígenos CD36/metabolismo , Citrus/química , Dislipidemias/complicações , Dislipidemias/metabolismo , Células Espumosas/metabolismo , Frutas/química , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Hipolipemiantes/isolamento & purificação , Transferases Intramoleculares/antagonistas & inibidores , Transferases Intramoleculares/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Simulação de Acoplamento Molecular , Óleos Vegetais/isolamento & purificação , Células RAW 264.7
19.
Circ Heart Fail ; 13(6): e006552, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32498623

RESUMO

BACKGROUND: Ex situ heart perfusion (ESHP) preserves the donated heart in a perfused, beating condition preventing cold storage-related ischemia and provides a platform to evaluate myocardial viability during preservation. However, myocardial function declines gradually during ESHP. Extracorporeal circulation systems are associated with the induction of systemic inflammatory and stress responses. Our aim was to evaluate the incidence of inflammation and induction of endoplasmic reticulum stress responses during an extended period of ESHP. METHODS: Cardiac function, myocardial tissue injury, markers of inflammation, oxidative stress, and endoplasmic reticulum stress were assessed in healthy pig hearts, perfused for 12 hours either in nonworking mode (non-WM=7) or working mode (WM, n=6). RESULTS: Cardiac function declined during ESHP but was significantly better preserved in the hearts perfused in WM (median 11-hour cardiac index/1-hour cardiac index: WM=27% versus non-WM=9.5%, P=0.022). Myocardial markers of endoplasmic reticulum stress were expressed higher in ESHP hearts compared with in vivo samples. The proinflammatory cytokines and oxidized low-density lipoprotein significantly increased in the perfusate throughout the perfusion in both perfusion groups. The left ventricular expression of the cytokines and malondialdehyde was induced in non-WM, whereas it was not different between WM and in vivo. CONCLUSIONS: Myocardial function declines during ESHP regardless of perfusion mode. However, ESHP in WM may lead to superior preservation of myocardial function and viability. Both inflammation and endoplasmic reticulum stress responses are significantly induced during ESHP and may contribute to the myocardial functional decline, representing a potential therapeutic target to improve the clinical donor heart preservation.


Assuntos
Estresse do Retículo Endoplasmático , Inflamação/metabolismo , Miocárdio/metabolismo , Estresse Oxidativo , Perfusão/efeitos adversos , Animais , Citocinas/metabolismo , Feminino , Inflamação/imunologia , Inflamação/patologia , Inflamação/fisiopatologia , Mediadores da Inflamação/metabolismo , Preparação de Coração Isolado , Lipoproteínas LDL/metabolismo , Malondialdeído/metabolismo , Miocárdio/imunologia , Miocárdio/patologia , Sus scrofa , Fatores de Tempo , Sobrevivência de Tecidos , Função Ventricular Esquerda
20.
J Vis Exp ; (159)2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32478759

RESUMO

Despite its limited analytical specificity and ruggedness, the thiobarbituric acid reactive substances (TBARS) assay has been widely used as a generic metric of lipid peroxidation in biological fluids. It is often considered a good indicator of the levels of oxidative stress within a biological sample, provided that the sample has been properly handled and stored. The assay involves the reaction of lipid peroxidation products, primarily malondialdehyde (MDA), with thiobarbituric acid (TBA), which leads to the formation of MDA-TBA2 adducts called TBARS. TBARS yields a red-pink color that can be measured spectrophotometrically at 532 nm. The TBARS assay is performed under acidic conditions (pH = 4) and at 95 °C. Pure MDA is unstable, but these conditions allow the release of MDA from MDA bis(dimethyl acetal), which is used as the analytical standard in this method. The TBARS assay is a straightforward method that can be completed in about 2 h. Preparation of assay reagents are described in detail here. Budget-conscious researchers can use these reagents for multiple experiments at a low cost rather than buying an expensive TBARS assay kit that only permits construction of a single standard curve (and thus can only be used for one experiment). The applicability of this TBARS assay is shown in human serum, low density lipoproteins, and cell lysates. The assay is consistent and reproducible, and limits of detection of 1.1 µM can be reached. Recommendations for the use and interpretation of the spectrophotometric TBARS assay are provided.


Assuntos
Bioensaio/métodos , Estresse Oxidativo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Colorimetria , Células Hep G2 , Humanos , Limite de Detecção , Peroxidação de Lipídeos , Lipoproteínas LDL/metabolismo , Malondialdeído/sangue , Oxirredução , Padrões de Referência , Reprodutibilidade dos Testes
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