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1.
PLoS One ; 15(7): e0235553, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614927

RESUMO

Aortic aneurysm refers to dilatation of the aorta due to loss of elasticity and degenerative weakening of its wall. A preventive role for osteoprotegerin (Opg) in the development of abdominal aortic aneurysm has been reported in the CaCl2-induced aneurysm model, whereas Opg was found to promote suprarenal aortic aneurysm in the AngII-induced ApoE knockout mouse aneurysm model. To determine whether there is a common underlying mechanism to explain the impact of Opg deficiency on the vascular structure of the two aneurysm models, we analyzed suprarenal aortic tissue of 6-month-old ApoE-/-Opg-/- mice after AngII infusion for 28 days. Less aortic dissection and aortic lumen dilatation, more adventitial thickening, and higher expression of collagen I and Trail were observed in ApoE-/-Opg-/- mice relative to ApoE-/-Opg+/+ mice. An accumulation of α-smooth muscle actin and vimentin double-positive myofibroblasts was noted in the thickened adventitia of ApoE-/-Opg-/- mice. Our results suggest that fibrotic remodeling of the aorta induced by myofibroblast accumulation might be an important pathological event which tends to limit AngII-induced aortic dilatation in ApoE -/-Opg-/- mice.


Assuntos
Túnica Adventícia/patologia , Aneurisma da Aorta Abdominal/patologia , Osteoprotegerina/genética , Túnica Adventícia/fisiologia , Angiotensina II/farmacologia , Animais , Aorta Abdominal/patologia , Aorta Abdominal/fisiologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Colesterol/sangue , Colágeno Tipo I/metabolismo , Modelos Animais de Doenças , Fibrose , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miofibroblastos/citologia , Miofibroblastos/metabolismo , Osteoprotegerina/deficiência , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Regulação para Cima/efeitos dos fármacos
2.
Arterioscler Thromb Vasc Biol ; 40(6): e166-e179, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32349534

RESUMO

OBJECTIVE: Recent studies suggest that the P2Y12 (P2Y purinoceptor 12) receptor of vascular smooth muscle cells in atherosclerotic plaques aggravates atherosclerosis, and P2Y12 receptor inhibitors such as CDL (clopidogrel) may effectively treat atherosclerosis. It is imperative to identify an effective biomarker for reflecting the P2Y12 receptor expression on vascular smooth muscle cells in plaques. Approach and Results: We found that there was a positive correlation between the level of circulating sLRP1 (soluble low-density lipoprotein receptor-related protein 1) and the number of LRP1+ α-SMA+ (α-smooth muscle actin), P2Y12+, or P2Y12+ LRP1+ cells in plaques from apoE-/- mice fed a high-fat diet. Furthermore, activation of the P2Y12 receptor increased the expression and shedding of LRP1 in vascular smooth muscle cells by inhibiting cAMP (3'-5'-cyclic adenosine monophosphate)/PKA (protein kinase A)/SREBP-2 (sterol regulatory element binding transcription factor 2). Conversely, genetic knockdown or pharmacological inhibition of the P2Y12 receptor had the opposite effects. Additionally, CDL decreased the number of lesional LRP1+ α-SMA+ cells and the levels of circulating sLRP1 by activating cAMP/PKA/SREBP-2 in apoE-/- mice fed a high-fat diet. CONCLUSIONS: Our study suggests that sLRP1 may be a biomarker that reflects the P2Y12 receptor level in plaques and has the potential to be an indicator for administering P2Y12 receptor inhibitors for patients with atherosclerosis.


Assuntos
Biomarcadores/análise , Expressão Gênica , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/análise , Placa Aterosclerótica/metabolismo , Receptores Purinérgicos P2Y12/genética , Actinas/análise , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Apolipoproteínas E/fisiologia , Clopidogrel/farmacologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dieta Hiperlipídica , Técnicas de Silenciamento de Genes , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/química , Músculo Liso Vascular/metabolismo , Placa Aterosclerótica/química , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Receptores Purinérgicos P2Y12/efeitos dos fármacos , Receptores Purinérgicos P2Y12/fisiologia , Transdução de Sinais , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
3.
Clin Sci (Lond) ; 134(9): 1049-1061, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32309850

RESUMO

Abdominal aortic aneurysm (AAA) is an important cause of mortality in older adults. Chronic inflammation and excessive matrix remodelling are considered important in AAA pathogenesis. Kinins are bioactive peptides important in regulating inflammation. Stimulation of the kinin B2 receptor has been previously reported to promote AAA development and rupture in a mouse model. The endogenous B2 receptor agonist, bradykinin, is generated from the kallikrein-kinin system following activation of plasma kallikrein by Factor XII (FXII). In the current study whole-body FXII deletion, or neutralisation of activated FXII (FXIIa), inhibited expansion of the suprarenal aorta (SRA) of apolipoprotein E-deficient mice in response to angiotensin II (AngII) infusion. FXII deficiency or FXIIa neutralisation led to decreased aortic tumor necrosis factor-α-converting enzyme (TACE/a disintegrin and metalloproteinase-17 (aka tumor necrosis factor-α-converting enzyme) (ADAM-17)) activity, plasma kallikrein concentration, and epithelial growth factor receptor (EGFR) phosphorylation compared with controls. FXII deficiency or neutralisation also reduced Akt1 and Erk1/2 phosphorylation and decreased expression and levels of active matrix metalloproteinase (Mmp)-2 and Mmp-9. The findings suggest that FXII, kallikrein, ADAM-17, and EGFR are important molecular mediators by which AngII induces aneurysm in apolipoprotein E-deficient mice. This could be a novel pathway to target in the design of drugs to limit AAA progression.


Assuntos
Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/patologia , Apolipoproteínas E/deficiência , Fator XII/antagonistas & inibidores , Proteína ADAM17/metabolismo , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Animais , Aneurisma da Aorta Abdominal/metabolismo , Modelos Animais de Doenças , Fator XII/metabolismo , Camundongos
4.
PLoS One ; 15(3): e0229240, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32119690

RESUMO

Various brain injuries lead to the activation of adult neural stem/progenitor cells in the mammalian hippocampus. Subsequent injury-induced neurogenesis appears to be essential for at least some aspects of the innate recovery in cognitive function observed following traumatic brain injury (TBI). It has previously been established that Apolipoprotein E (ApoE) plays a regulatory role in adult hippocampal neurogenesis, which is of particular interest as the presence of the human ApoE isoform ApoE4 leads to significant risk for the development of late-onset Alzheimer's disease, where impaired neurogenesis has been linked with disease progression. Moreover, genetically modified mice lacking ApoE or expressing the ApoE4 human isoform have been shown to impair adult hippocampal neurogenesis under normal conditions. Here, we investigate how controlled cortical impact (CCI) injury affects dentate gyrus development using hippocampal stereotactic injections of GFP-expressing retroviruses in wild-type (WT), ApoE-deficient and humanized (ApoE3 and ApoE4) mice. Infected adult-born hippocampal neurons were morphologically analyzed once fully mature, revealing significant attenuation of dendritic complexity and spine density in mice lacking ApoE or expressing the human ApoE4 allele, which may help inform how ApoE influences neurological diseases where neurogenesis is defective.


Assuntos
Apolipoproteína E3/metabolismo , Apolipoproteína E4/metabolismo , Apolipoproteínas E/deficiência , Lesões Encefálicas Traumáticas/patologia , Hipocampo/crescimento & desenvolvimento , Retroviridae/genética , Animais , Apolipoproteína E3/genética , Apolipoproteína E4/genética , Lesões Encefálicas Traumáticas/genética , Lesões Encefálicas Traumáticas/metabolismo , Modelos Animais de Doenças , Feminino , Vetores Genéticos/administração & dosagem , Hipocampo/metabolismo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Neurogênese , Neurônios/metabolismo
5.
J Nutr ; 150(5): 1167-1177, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32047914

RESUMO

BACKGROUND: Normalization of arterial inflammation inhibits atherosclerosis. The preventive role for protocatechuic acid (PCA) in early-stage atherosclerosis is well recognized; however, its therapeutic role in late-stage atherosclerosis remains unexplored. OBJECTIVE: We investigated whether PCA inhibits vulnerable atherosclerosis progression by normalizing arterial inflammation. METHODS: Thirty-wk-old male apolipoprotein E-deficient (Apoe-/-) mice with vulnerable atherosclerotic lesions in the brachiocephalic artery were fed the AIN-93G diet alone (control) or supplemented with 0.003% PCA (wt:wt) for 20 wk. Lesion size and composition, IL-1ß, and NF-κB in the brachiocephalic arteries, and serum lipid profiles, oxidative status, and proinflammatory cytokines (e.g., IL-1ß, monocyte chemoattractant protein-1, and serum amyloid A) were measured. Moreover, the effect of PCA on the inflammation response was evaluated in efferocytic macrophages from C57BL/6J mice. RESULTS: Compared with the control treatment, dietary PCA supplementation significantly reduced lesion size (27.5%; P < 0.05) and also improved lesion stability (P < 0.05) as evidenced by increased thin fibrous cap thickness (31.7%) and collagen accumulation (58.3%), reduced necrotic core size (37.6%) and cellular apoptosis (73.9%), reduced macrophage accumulation (45.1%), and increased vascular smooth muscle cell accumulation (51.5%). Moreover, PCA supplementation inhibited IL-1ß expression (53.7%) and NF-κB activation (64.4%) in lesions. However, PCA supplementation did not change serum lipid profiles, total antioxidant capacity, and inflammatory cytokines. In efferocytic macrophages, PCA at 0.5 and 1 µmol/L inhibited Il1b/IL-1ß mRNA (27.2-46.5%) and protein (29.2-49.6%) expression and NF-κB activation (67.0-80.3%) by upregulation of MER proto-oncogene tyrosine kinase (MERTK) and inhibition of mitogen-activated protein kinase 3/1 (MAPK3/1). Strikingly, the similar pattern of the MERTK and MAPK3/1 changes in lesional macrophages of mice after PCA intervention in vivo was recapitulated. CONCLUSION: PCA inhibits vulnerable lesion progression in mice, which might partially be caused by normalization of arterial inflammation by upregulation of MERTK and inhibition of MAPK3/1 in lesional macrophages.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Hidroxibenzoatos/administração & dosagem , Animais , Anti-Inflamatórios , Apolipoproteínas E/genética , Apolipoproteínas E/fisiologia , Células Cultivadas , Suplementos Nutricionais , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Interleucina-1beta/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , NF-kappa B/metabolismo , c-Mer Tirosina Quinase/genética , c-Mer Tirosina Quinase/fisiologia
6.
PLoS One ; 15(2): e0228415, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32084149

RESUMO

Ribose-cysteine is a synthetic compound designed to increase glutathione (GSH) synthesis. Low levels of GSH and the GSH-dependent enzyme, glutathione peroxidase (GPx), is associated with cardiovascular disease (CVD) in both mice and humans. Here we investigate the effect of ribose-cysteine on GSH, GPx, oxidised lipids and atherosclerosis development in apolipoprotein E-deficient (apoE-/-) mice. Female 12-week old apoE-/- mice (n = 15) were treated with 4-5 mg/day ribose-cysteine in drinking water for 8 weeks or left untreated. Blood and livers were assessed for GSH, GPx activity and 8-isoprostanes. Plasma alanine transferase (ALT) and lipid levels were measured. Aortae were quantified for atherosclerotic lesion area in the aortic sinus and brachiocephalic arch and 8-isoprostanes measured. Ribose-cysteine treatment significantly reduced ALT levels (p<0.0005) in the apoE-/- mice. Treatment promoted a significant increase in GSH concentrations in the liver (p<0.05) and significantly increased GPx activity in the liver and erythrocytes of apoE-/-mice (p<0.005). The level of 8-isoprostanes were significantly reduced in the livers and arteries of apoE-/- mice (p<0.05 and p<0.0005, respectively). Ribose-cysteine treatment showed a significant decrease in total and low density lipoprotein (LDL) cholesterol (p<0.05) with no effect on other plasma lipids with the LDL reduction likely through upregulation of scavenger receptor-B1 (SR-B1). Ribose-cysteine treatment significantly reduced atherosclerotic lesion area by >50% in both the aortic sinus and brachiocephalic branch (p<0.05). Ribose-cysteine promotes a significant GSH-based antioxidant effect in multiple tissues as well as an LDL-lowering response. These effects are accompanied by a marked reduction in atherosclerosis suggesting that ribose-cysteine might increase protection against CVD.


Assuntos
Antioxidantes/administração & dosagem , Apolipoproteínas E/deficiência , Aterosclerose/prevenção & controle , Cisteína/administração & dosagem , Substâncias Protetoras/administração & dosagem , Ribose/administração & dosagem , Animais , Antioxidantes/metabolismo , Aterosclerose/metabolismo , Aterosclerose/patologia , Cisteína/metabolismo , Feminino , Lipídeos/análise , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Oxirredução , Substâncias Protetoras/metabolismo , Ribose/metabolismo
7.
Ecotoxicol Environ Saf ; 192: 110308, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32058168

RESUMO

PM2.5 particles are regarded as prominent risk factors that contribute to the development of atherosclerosis. However, the composition of PM2.5 is rather complicated. This study aimed to provide a model particle that simulates the behavior of actual PM2.5, for subsequent use in exploring mechanisms and major complications arising from PM2.5. To establish model particles of PM2.5, a series of monodisperse SiO2 microspheres with different average grain diameters were mixed according to the size distribution of actual PM2.5. The organic carbon (OC) was removed from PM2.5 and coated onto the SiO2 model particle, to formulate simulant PM2.5. Results showed that the size distribution of the model particle was highly approximate to that of the PM2.5 core. The polycyclic aromatic hydrocarbon (PAHs) composition profile of the simulated PM2.5 were approximate to PM2.5, and loading efficiency was approximately 80%-120%. Furthermore, compared to the control, SiO2-only model particle had negligible cytotoxicity on cell viability and oxidative stress of HUVECs, and marginal effect on the lipid metabolism and atherosclerotic plaque formation in ApoE-/- mice. In contrast, simulated PM2.5 exhibited similar cytotoxic and detrimental effects on lipid metabolism and atherosclerotic plaque formation with actual PM2.5. Traffic-related PM2.5 had negative effects on endothelial function and led to the formation of atherosclerosis via oxidative stress. The simulated PM2.5 simulated the outcomes of actual PM2.5 exposure. Here, we show that SiO2 particle model cores coated with OC could significantly assist in the evaluation of the effects of specific organic compositions bound on PM2.5, specifically in the context of environmental health and safety.


Assuntos
Poluentes Atmosféricos/toxicidade , Apolipoproteínas E/deficiência , Material Particulado/química , Placa Aterosclerótica/induzido quimicamente , Dióxido de Silício/química , Poluentes Atmosféricos/química , Animais , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Dióxido de Silício/toxicidade , Emissões de Veículos/toxicidade
8.
Am J Pathol ; 190(5): 1118-1136, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32084369

RESUMO

Fibroblast activation protein (FAP) has been established as an inducible and mesenchymal cell-specific mediator of disease progression in cancer and fibrosis. Atherosclerosis is a fibroinflammatory disease, and FAP was previously reported to be up-regulated in human atherosclerotic plaques compared with normal vessel. We investigated the spatial and temporal distribution of Fap-expressing cells in a murine model of atherosclerosis and used a genetic approach to determine if and how Fap affected disease progression. Fap was found to be expressed predominantly on vascular smooth muscle cells in lesions of athero-prone Apoe-/- mice. Global deletion of Fap (Fap-/-) in Apoe-/- mice accelerated atherosclerotic disease progression in both males and females, with the effect observed earlier in males. Sex-specific effects on lesion morphology were observed. Relative levels of extracellular matrix, fibrotic, and inflammatory cell content were comparable in lesions in male mice regardless of Fap status. In contrast, lesions in Fap-/- female mice were characterized by a more fibrotic composition due to a reduction in inflammation, specifically a reduction in Mox macrophages. Combined, these data suggest that Fap restrains the progression of atherosclerosis and may contribute to the sexually dimorphic susceptibility to atherosclerosis by regulating the balance between inflammation (an indicator of vulnerability to plaque rupture) and fibrosis (an indicator of plaque stability).


Assuntos
Aterosclerose/metabolismo , Fibrose/metabolismo , Gelatinases/metabolismo , Inflamação/metabolismo , Proteínas de Membrana/metabolismo , Serina Endopeptidases/metabolismo , Caracteres Sexuais , Animais , Apolipoproteínas E/deficiência , Feminino , Masculino , Camundongos , Camundongos Knockout para ApoE
9.
Clin Sci (Lond) ; 134(5): 439-458, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32091078

RESUMO

Sphingolipids have been implicated in the etiology of atherosclerosis. The commonly used sphingolipid inhibitors, myriocin (a ceramide inhibitor) and d-PDMP (d-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol, a glycosphingolipid inhibitor), have shown therapeutic potential but their efficacy and their underlying mechanisms remain unclear. Here, apolipoprotein E-deficient (apoE-/-) mice were fed a high-fat diet (HFD) and treated with a control, myriocin, d-PDMP, or atorvastatin for 12 weeks. We analyzed the effects of these drugs on the size and detailed composition of atherosclerotic plaques. Molecular biological approaches were used to explore how the inhibitors affect lipid metabolism and foam-cell formation. Treatment with myriocin or d-PDMP led to smaller and less vulnerable atherosclerotic lesions and was almost as effective as atorvastatin. Sphingolipid inhibitors down-regulated the expression of monocyte chemotactic protein 1 (MCP-1) and its receptor chemoattractant cytokine receptor 2 (CCR2), which play a key role in monocyte recruitment. They also decreased pro-inflammatory Ly-6chigh monocytes and influenced the uptake of modified LDL by down-regulating the expression of cluster of differentiation 36 (CD36) and lectin-like oxidized LDL (ox-LDL) receptor-1 (LOX-1). The inhibitors exhibited the advantage of maintaining normal glucose homeostasis compared with atorvastatin. These findings reveal for the first time that the modulation of sphingolipid synthesis can effectively alleviate atherosclerosis progression by preventing lipid uptake and reducing inflammatory responses in the arterial walls.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/prevenção & controle , Ácidos Graxos Monoinsaturados/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Morfolinas/farmacologia , Vasculite/prevenção & controle , Animais , Anticolesterolemiantes/farmacologia , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Atorvastatina/farmacologia , Transporte Biológico/efeitos dos fármacos , Ceramidas/antagonistas & inibidores , Ceramidas/metabolismo , Glicoesfingolipídeos/antagonistas & inibidores , Glicoesfingolipídeos/metabolismo , Imunossupressores/farmacologia , Lipídeos/sangue , Lipídeos/farmacocinética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Placa Aterosclerótica/prevenção & controle , Vasculite/metabolismo
10.
Oxid Med Cell Longev ; 2020: 3602824, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32064021

RESUMO

Abdominal aortic aneurysm (AAA) is a vascular disorder that is considered a chronic inflammatory disease. However, the precise molecular mechanisms involved in AAA have not been fully elucidated. Recently, significant progress has been made in understanding the function and mechanism of action of inhibitor of kappa B kinase epsilon (IKKε) in inflammatory and metabolic diseases. The angiotensin II- (Ang II-) induced or pharmacological inhibitors were established to test the effects of IKKε on AAA in vivo. After mice were continuously stimulated with Ang II for 28 days, morphologically, we found that knockout of IKKε reduced AAA formation and drastically reduced maximal diameter and severity. We also observed a decrease in elastin degradation and medial destruction, which were independent of systolic blood pressure or plasma cholesterol concentrations. Western blot analyses and immunohistochemical staining were carried out to measure IKKε expression in AAA tissues and cell lines. AAA phenotype of mice was measured by ultrasound and biochemical indexes. In zymography, immunohistology staining, immunofluorescence staining, and reactive oxygen species (ROS) analysis, TUNEL assay was used to examine the effects of IKKε on AAA progression in AAA mice. IKKε deficiency significantly inhibited inflammatory macrophage infiltration, matrix metalloproteinase (MMP) activity, ROS production, and vascular smooth muscle cell (VSMC) apoptosis. We used primary mouse aortic VSMC isolated from apolipoprotein E (Apoe) -/- and Apoe-/-IKKε -/- mice. Mechanistically, IKKε deficiency blunted the activation of the ERK1/2 pathway. The IKKε inhibitor, amlexanox, has the same impact in AAA. Our results demonstrate a critical role of IKKε in AAA formation induced by Ang II in Apoe-/- mice. Targeting IKKε may constitute a novel therapeutic strategy to prevent AAA progression.


Assuntos
Angiotensina II/toxicidade , Aneurisma da Aorta Abdominal/metabolismo , Apoptose/genética , Quinase I-kappa B/deficiência , Inflamação/metabolismo , Estresse Oxidativo/genética , Idoso , Animais , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/enzimologia , Aneurisma da Aorta Abdominal/fisiopatologia , Apolipoproteínas E/deficiência , Apoptose/efeitos dos fármacos , Elastina/metabolismo , Feminino , Humanos , Quinase I-kappa B/antagonistas & inibidores , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Inflamação/genética , Inflamação/patologia , Sistema de Sinalização das MAP Quinases/genética , Macrófagos/metabolismo , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Espécies Reativas de Oxigênio/metabolismo
11.
FASEB J ; 34(2): 3367-3378, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31919912

RESUMO

Ppardδ, one of the lipid-activated nuclear receptor expressed in many cell types to activate gene transcription, also regulates cellular functions other than lipid metabolism. The mechanism regulating the function of antigen-presenting cells during the development of atherosclerosis is not fully understood. Here we aimed to study the involvement of PPARδ in CD11c+ cells in atherosclerosis. We used the Cre-loxP approach to make conditional deletion of Ppard in CD11c+ cells in mice on Apoe-/- background, which were fed with high cholesterol diet to develop atherosclerosis. Ppard deficiency in CD11c+ cells attenuated atherosclerotic plaque formation and infiltration of myeloid-derived dendritic cells (DCs) and T lymphocytes. Reduced lesion was accompanied by reduced activation of dendritic cells, and also a reduction of activation and differentiation of T cells to Th1 cells. In addition, DC migration to lymph node was also attenuated with Ppard deletion. In bone marrow-derived DCs, Ppard deficiency reduced palmitic acid-induced upregulation of co-stimulatory molecules and pro-inflammatory cytokine IL12 and TNFα. Our results indicated PPARδ activation by fatty acid resulted in the activation of myeloid DCs and subsequent polarization of T lymphocytes, which contributed to atherosclerosis in Apoe-/- mice. These findings also reveal the potential regulatory role of PPARδ in antigen presentation to orchestrate the immune responses during atherosclerosis.


Assuntos
Aterosclerose/metabolismo , Células Dendríticas/metabolismo , Deleção de Genes , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/genética , Antígenos CD11/genética , Antígenos CD11/metabolismo , Células Cultivadas , Interleucina-12/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Receptores Citoplasmáticos e Nucleares/genética , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
12.
Artif Cells Nanomed Biotechnol ; 48(1): 169-179, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852323

RESUMO

Magnetic resonance imaging (MRI) is an essential tool for the diagnosis of atherosclerosis, a chronic cardiovascular disease. MRI primarily uses superparamagnetic iron oxide (SPIO) as a contrast agent. However, SPIO integrated with therapeutic drugs has rarely been studied. In this study, we explored biocompatible paramagnetic iron-oxide nanoparticles (NPs) in a complex with low pH-sensitive cyclodextrin for the diagnostic imaging and treatment of atherosclerosis. The NPs were conjugated with profilin-1 antibody (PFN1) to specifically target vascular smooth muscle cells (VSMCs) in the atherosclerotic plaque and integrated with the anti-inflammatory drug, rapamycin. The PFN1-CD-MNPs were easily binded to the VSMCs, indicating their good biocompatibility and low renal toxicity over the long term. Ex vivo near-infrared fluorescence (NIRF) imaging and in vivo MRI indicated the accumulation of PFN1-CD-MNPs in the atherosclerotic plaque. The RAP@PFN1-CD-MNPs alleviated the progression of arteriosclerosis. Thus, PFN1-CD-MNPs served not only as multifunctional imaging probes but also as nanovehicles for the treatment of atherosclerosis.


Assuntos
Imagem por Ressonância Magnética , Nanomedicina , Imagem Óptica , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/tratamento farmacológico , Animais , Apolipoproteínas E/deficiência , Meios de Contraste/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Lipídeos/sangue , Nanopartículas de Magnetita/química , Masculino , Camundongos , Placa Aterosclerótica/sangue , Placa Aterosclerótica/metabolismo , Sirolimo/química , Sirolimo/farmacologia , Sirolimo/uso terapêutico
13.
Redox Biol ; 28: 101338, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634818

RESUMO

NADPH oxidase (Nox)-derived reactive oxygen species (ROS) are instrumental in all inflammatory phases of atherosclerosis. Dysregulated histone deacetylase (HDAC)-related epigenetic pathways have been mechanistically linked to alterations in gene expression in experimental models of cardiovascular disorders. Hitherto, the relation between HDAC and Nox in atherosclerosis is not known. We aimed at uncovering whether HDAC plays a role in mediating Nox up-regulation, oxidative stress, inflammation, and atherosclerotic lesion progression. Human non-atherosclerotic and atherosclerotic arterial samples, ApoE-/- mice, and in vitro polarized monocyte-derived M1/M2-macrophages (Mac) were examined. Male ApoE-/- mice, maintained on normal or high-fat, cholesterol-rich diet, were randomized to receive 10 mg/kg suberoylanilide hydroxamic acid (SAHA), a pan-HDAC inhibitor, or its vehicle, for 4 weeks. In the human/animal studies, real-time PCR, Western blot, lipid staining, lucigenin-enhanced chemiluminescence assay, and enzyme-linked immunosorbent assay were employed. The protein levels of class I, class IIa, class IIb, and class IV HDAC isoenzymes were significantly elevated both in human atherosclerotic tissue samples and in atherosclerotic aorta of ApoE-/- mice. Treatment of ApoE-/- mice with SAHA reduced significantly the extent of atherosclerotic lesions, and the aortic expression of Nox subtypes, NADPH-stimulated ROS production, oxidative stress and pro-inflammatory markers. Significantly up-regulated HDAC and Nox subtypes were detected in inflammatory M1-Mac. In these cells, SAHA reduced the Nox1/2/4 transcript levels. Collectively, HDAC inhibition reduced atherosclerotic lesion progression in ApoE-/- mice, possibly by intertwined mechanisms involving negative regulation of Nox expression and inflammation. The data propose that HDAC-oriented pharmacological interventions could represent an effective therapeutic strategy in atherosclerosis.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/etiologia , Aterosclerose/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , NADPH Oxidases/genética , Estresse Oxidativo/efeitos dos fármacos , Animais , Aorta/metabolismo , Aorta/patologia , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Biópsia , LDL-Colesterol/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Epigênese Genética , Humanos , Masculino , Camundongos , Camundongos Knockout , NADPH Oxidases/metabolismo , Oxirredução , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Espécies Reativas de Oxigênio/metabolismo
14.
Lipids Health Dis ; 18(1): 208, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796057

RESUMO

BACKGROUND: MicroRNAs are short non-coding RNAs that regulate gene expression. The aim of this study was to gain an understanding of the possible role of the miR-106b~ 25 microRNA cluster in regulating atherosclerosis in mice. METHODS: MiR-106b~ 25 knockout mice were outcrossed into Apolipoprotein E (ApoE) knockout background to generate double knockout mice. At 36 weeks of age, lesion size was evaluated in the aortic sinus by oil-red-O staining. RESULTS: Lesion size was 2-fold smaller in double KO mice in comparison to ApoE KO mice. In addition, collagen staining showed a trend towards a stable plaque phenotype in the double KO mice. Lipid profiling of plasma samples of double KO and ApoE KO mice using FPLC revealed over 2-fold decrease in Very low density lipoprotein (VLDL) cholesterol content and a 50% decrease in low density lipoprotein (LDL) cholesterol content in double KO mice. By using target prediction software, we have identified several possible targets for the miR-106b~ 25 cluster including the VLDL and LDL receptors. We found that upon feeding miR-106b~ 25 KO mice with high fat diet, the expression of LDL and VLDL receptors was higher than in the wild-type mice, suggesting the miR-106b~ 25 cluster regulates atherosclerosis by influencing clearance of VLDL and LDL from the plasma. CONCLUSIONS: We identified the miR-106b~ 25 cluster as a novel regulator of atherosclerosis in ApoE KO mice, presumably by regulating plasma cholesterol levels.


Assuntos
Apolipoproteínas E/genética , Aterosclerose/genética , MicroRNAs/genética , Placa Aterosclerótica/genética , Receptores de LDL/genética , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/patologia , Apolipoproteínas E/deficiência , Aterosclerose/metabolismo , Aterosclerose/patologia , Sequência de Bases , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Dieta Hiperlipídica/métodos , Gorduras na Dieta/administração & dosagem , Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , MicroRNAs/metabolismo , Família Multigênica , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Receptores de LDL/metabolismo , Deleção de Sequência
15.
BMC Immunol ; 20(1): 47, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31823769

RESUMO

BACKGROUND: Expansion of type 2 innate lymphoid cells (ILC2s) in hypercholesterolaemic mice protects against atherosclerosis while different ILC2 subsets have been described (natural, inflammatory) based on their suppression of tumorigenicity 2 (ST2) and killer-cell lectin like receptor G1 (KLRG1) expression. The aim of the current study is to characterize the interleukin 25 (IL25)-induced splenic ILC2 population (Lin-CD45+IL17RB+ICOS+IL7raintermediate) and address its direct role in experimental atherosclerosis by its adoptive transfer to hypercholesterolaemic apolipoprotein E deficient (apoE-/-) mice. RESULTS: Immunomagnetically enriched, FACS-sorted ILC2s from the spleens of IL-25 treated apoE-/- mice were stained for KLRG1 and ST2 directly upon cell obtainment or in vitro cell expansion for flow cytometric analysis. IL25-induced splenic ILC2s express high levels of both KLRG1 and ST2. However, both markers are downregulated upon in vitro cell expansion. In vitro expanded splenic ILC2s were intraperitoneally transferred to apoE-/- recipients on high fat diet. ApoE-/- mice that received in vitro expanded splenic ILC2s had decreased lipid content in subvalvular heart and brachiocephalic artery (BCA) plaques accompanied by increased peritoneal B1 cells, activated eosinophils and alternatively activated macrophages (AAMs) as well as anti-phosphorylcholine (PC) immunoglobulin (Ig) M in plasma. CONCLUSIONS: With the current data we designate the IL25-induced ILC2 population to decrease the lipid content of atherosclerotic lesions in apoE-/- mice and we directly link the induction of B1 cells and the atheroprotective anti-PC IgM antibodies with ILC2s.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/etiologia , Aterosclerose/metabolismo , Imunidade Inata , Lipídeos/sangue , Linfócitos/imunologia , Linfócitos/metabolismo , Transferência Adotiva , Animais , Aterosclerose/patologia , Biomarcadores , Citocinas/metabolismo , Modelos Animais de Doenças , Imunofenotipagem , Camundongos , Camundongos Knockout
16.
Int J Mol Sci ; 20(24)2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31817202

RESUMO

Vanadium is a transition metal widely distributed in the Earth's crust, and is a major contaminant in fossil fuels. Its pathological effect and regulation in atherosclerosis remain unclear. We found that intranasal administration of the vanadium derivative NaVO3 significantly increased plasma and urinary vanadium levels and induced arterial lipid accumulation and atherosclerotic lesions in apolipoprotein E-deficient knockout mice (ApoE-/-) murine aorta compared to those in vehicle-exposed mice. This was accompanied by an increase in plasma reactive oxygen species (ROS) and interleukin 6 (IL-6) levels and a decrease in the vascular smooth muscle cell (VSMC) differentiation marker protein SM22α in the atherosclerotic lesions. Furthermore, exposure to NaVO3 or VOSO4 induced cytosolic ROS generation and IL-6 production in VSMCs and promoted VSMC synthetic differentiation, migration, and proliferation. The anti-oxidant N-acetylcysteine (NAC) not only suppresses IL-6 production and VSMC pathological responses including migration and proliferation but also prevents atherosclerosis in ApoE-/- mice. Inhibition experiments with NAC and pharmacological inhibitors demonstrated that NaVO3-induced IL-6 production is signaled by ROS-triggered p38-mediated NF-κB-dependent pathways. Neutralizing anti-IL-6 antibodies impaired NaVO3-mediated VSMC migration and proliferation. We concluded that NaVO3 exposure activates the ROS-triggering p38 signaling to selectively induce NF-κB-mediated IL-6 production. These signaling pathways induce VSMC synthetic differentiation, migration, and proliferation, leading to lipid accumulation and atherosclerosis.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Interleucina-6/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Vanadatos/toxicidade , Acetilcisteína/farmacologia , Animais , Aorta/patologia , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/induzido quimicamente , Aterosclerose/patologia , Aterosclerose/veterinária , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas dos Microfilamentos/metabolismo , Proteínas Musculares/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
17.
Clín. investig. arterioscler. (Ed. impr.) ; 31(6): 251-260, nov.-dic. 2019. tab, graf
Artigo em Inglês | IBECS | ID: ibc-185150

RESUMO

Introduction: High Density Lipoproteins (HDL) are dysfunctional in hypercholesterolemia patients. The hypothesis was tested that nicotinamide (NAM) administration will influence HDL metabolism and reverse cholesterol transport from macrophages to the liver and feces in vivo (m-RCT) in a murine model of hypercholesterolemia. Methods: Apolipoprotein E-deficient (KOE) mice were challenged with a high-fat diet for 4 weeks. The effect of different doses of NAM on cholesterol metabolism, and the ability of HDL to promote m-RCT was assessed. Results: The administration of NAM to KOE mice produced an increase (∼1.5-fold; P < 0.05) in the plasma levels of cholesterol, which was mainly accounted for by the non-HDL fraction. NAM produced a [3H]-cholesterol plasma accumulation (∼1.5-fold) in the m-RCT setting. As revealed by kinetic analysis, the latter was mainly explained by an impaired clearance of circulating non-HDL (∼0.8-fold). The relative content of [3H]-tracer was lowered in the livers (∼0.6-fold) and feces (> 0.5-fold) of NAM-treated mice. This finding was accompanied by a significant (or trend close to significance) up-regulation of the relative gene expression of Abcg5 and Abcg8 in the liver (Abcg5: 2.9-fold; P < 0.05; Abcg8: 2.4-fold; P = 0.06) and small intestine (Abcg5: 2.1-fold; P = 0.15; Abcg8: 1.9-fold; P < 0.05) of high-dose, NAM-treated mice. Conclusion: The data from this study show that the administration of NAM to KOE mice impaired m-RCT in vivo. This finding was partly due to a defective hepatic clearance of plasma non-HDL


No dispnible


Assuntos
Animais , Camundongos , Apolipoproteínas E/deficiência , Niacinamida/administração & dosagem , Colesterol/análise , Hipercolesterolemia/diagnóstico , Hipercolesterolemia/tratamento farmacológico , Apolipoproteínas E/administração & dosagem , Niacinamida/metabolismo , Colesterol/metabolismo , Gorduras na Dieta , Expressão Gênica , HDL-Colesterol
18.
Biomed Res Int ; 2019: 8348430, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886257

RESUMO

Vascular calcification is an independent risk factor for plaque instability and is associated with endothelial cell function. Here, we investigated the role of endothelial cell function in the calcification of atherosclerotic plaques. We hypothesized that atherosclerosis would be associated with endothelial dysfunction and that bosentan (Tracleer®), a dual endothelin-receptor antagonist, would preserve endothelial cell function in an apolipoprotein E-deficient (ApoE-/-) mouse model of atherosclerosis. Accordingly, 4-6-week-old ApoE-/- mice were fed a high-fat diet and treated with bosentan, and the effects of this treatment on body weight and blood lipid concentrations was evaluated. Endothelial damage in the aortic arch was assessed immunohistochemically to detect the proapoptotic proteins PDCD4, caspase-3, and Bax and the antiapoptotic protein Bcl-2. Notably, bosentan treatment was associated with decreased concentrations of these proteins and of blood lipids in ApoE-/- mice. Consistent with these findings, we observed increased concentrations of miRNA-21 and PDCD4 mRNA expression in the aortic arch endothelium after bosentan treatment. We conclude that bosentan can prevent endothelial cell death and protect against atherosclerosis in ApoE-deficient mice by upregulating miRNA-21.


Assuntos
Apolipoproteínas E/deficiência , Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Bosentana/uso terapêutico , MicroRNAs/metabolismo , Substâncias Protetoras/uso terapêutico , Animais , Aorta Torácica/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Aterosclerose/sangue , Aterosclerose/patologia , Peso Corporal/efeitos dos fármacos , Bosentana/farmacologia , Caspase 3/metabolismo , Dieta Hiperlipídica , Lipídeos/sangue , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteína X Associada a bcl-2/metabolismo
19.
Oxid Med Cell Longev ; 2019: 5181429, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781340

RESUMO

Objective: Atherogenic lipoproteins may impair vascular reactivity consecutively causing tissue damage in multiple organs via abnormal perfusion and excessive reactive oxygen species generation. We tested the hypothesis that chronic hypercholesterolemia causes endothelial dysfunction and cell loss in the retina. Methods: Twelve-month-old apolipoprotein E-deficient (ApoE-/-) mice and age-matched wild-type controls were used in this study (n = 8 per genotype for each experiment). Intraocular pressure, blood pressure, and ocular perfusion pressure were determined. Retinal arteriole responses were studied in vitro, and reactive oxygen and nitrogen species were quantified in the retinal and optic nerve cryosections. The expression of the lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and the NADPH oxidase isoforms, NOX1, NOX2, and NOX4, were determined in retinal cryosections by immunofluorescence microscopy. Pro- and antioxidant redox genes were quantified in retinal explants by PCR. Moreover, cell number in the retinal ganglion cell layer and axon number in the optic nerve was calculated. Results: Responses to the endothelium-dependent vasodilator, acetylcholine, were markedly impaired in retinal arterioles of ApoE-/- mice (P < 0.01). LOX-1 (P = 0.0007) and NOX2 (P = 0.0027) expressions as well as levels of reactive oxygen species (P = 0.0022) were increased in blood vessels but not in other retinal structures. In contrast, reactive nitrogen species were barely detectable in both mouse genotypes. Messenger RNA for HIF-1α, VEGF-A, NOX1, and NOX2, but also for various antioxidant redox genes was elevated in the retina of ApoE-/- mice. Total cell number in the retinal ganglion cell layer did not differ between ApoE-/- and wild-type mice (P = 0.2171). Also, axon number in the optic nerve did not differ between ApoE-/- and wild-type mice (P = 0.6435). Conclusion: Apolipoprotein E deficiency induces oxidative stress and endothelial dysfunction in retinal arterioles, which may trigger hypoxia in the retinal tissue. Oxidative stress in nonvascular retinal tissue appears to be prevented by the upregulation of antioxidant redox enzymes, resulting in neuron preservation.


Assuntos
Apolipoproteínas E/deficiência , Endotélio Vascular/metabolismo , Hipercolesterolemia/metabolismo , Estresse Oxidativo , Retina/metabolismo , Doenças Retinianas/metabolismo , Vasos Retinianos/metabolismo , Animais , Apolipoproteínas E/metabolismo , Arteríolas/metabolismo , Arteríolas/patologia , Endotélio Vascular/patologia , Hipercolesterolemia/genética , Hipercolesterolemia/patologia , Camundongos , Camundongos Knockout para ApoE , Retina/patologia , Doenças Retinianas/genética , Doenças Retinianas/patologia , Vasos Retinianos/patologia
20.
Med Sci Monit ; 25: 7966-7975, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31645538

RESUMO

BACKGROUND This study aimed to investigate the effects of dimethyl fumarate (DMF) on thoracic aortic atherosclerosis in the apolipoprotein E (apo-E)-deficient mouse model with streptozotocin (STZ)-induced hyperglycemia, and the signaling pathways involved. MATERIAL AND METHODS Eight-week-old ApoE-/- male mice (n=30) were randomly divided into three groups: the Control group (ApoE-/-) (n=10); the diabetic model (STZ) group (n=10); and the DMF-treated (25 mg/kg) diabetic model (DMF+STZ) group (n=10). The area of the thoracic aortic atherosclerosis was determined by histology. Reactive oxygen species (ROS) levels in mouse serum and homogenates of the thoracic aorta were determined by colorimetry. Levels of nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase subunit gp91phox were detected by immunological hybridization, and levels of heme oxygenase-1 (HO-1) were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS Compared with the Control group, in the STZ group, the area of aortic atherosclerosis was significantly increased, the levels of serum and aortic ROS, HO-1, nuclear factor-kappaB (NF-kappaB), intercellular adhesion molecule 1 (ICAM-1), and gp91phox were increased, and nuclear factor erythroid 2-related factor 2 (Nrf2), endothelial nitric oxide synthase (eNOS), and phosphorylated eNOS (p-eNOS) were significantly reduced. Compared with the STZ group, in the DMF+STZ group, the area of aortic atherosclerosis was significantly reduced, the levels of serum and aortic ROS, HO-1, NF-kappaB, ICAM-1, and gp91phox were significantly reduced, and Nrf2, eNOS, and p-eNOS were significantly increased. CONCLUSIONS In the apo-E-deficient mouse model with STZ-induced hyperglycemia, DMF reduced the development of atherosclerosis of the thoracic aorta through the nuclear factor erythroid 2-related factor 2/antioxidant response element (Nrf2/ARE) signaling pathway.


Assuntos
Aterosclerose/tratamento farmacológico , Fumarato de Dimetilo/farmacologia , Animais , Elementos de Resposta Antioxidante/fisiologia , Aorta/patologia , Apolipoproteínas E/deficiência , China , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Heme Oxigenase-1/metabolismo , Hiperglicemia/induzido quimicamente , Hiperglicemia/complicações , Inflamação/patologia , Masculino , Camundongos , Camundongos Knockout , NADPH Oxidases/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fragmentos de Peptídeos/deficiência , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estreptozocina/farmacologia
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