ABSTRACT
Abstract Background: Restenosis after percutaneous coronary intervention in coronary heart disease remains an unsolved problem. Clusterin (CLU) (or Apolipoprotein [Apo] J) levels have been reported to be elevated during the progression of postangioplasty restenosis and atherosclerosis. However, its role in neointimal hyperplasia is still controversial. Objective: To elucidate the role Apo J in neointimal hyperplasia in a rat carotid artery model in vivo with or without rosuvastatin administration. Methods: Male Wistar rats were randomly divided into three groups: the control group (n = 20), the model group (n = 20) and the statin intervention group (n = 32). The rats in the intervention group were given 10mg /kg dose of rosuvastatin. A 2F Fogarty catheter was introduced to induce vascular injury. Neointima formation was analyzed 1, 2, 3 and 4 weeks after balloon injury. The level of Apo J was measured by real-time PCR, immunohistochemistry and western blotting. Results: Intimal/medial area ratio (intimal/medial, I/M) was increased after balloon-injury and reached the maximum value at 4weeks in the model group; I/M was slightly increased at 2 weeks and stopped increasing after rosuvastatin administration. The mRNA and protein levels of Apo J in carotid arteries were significantly upregulated after rosuvastatin administration as compared with the model group, and reached maximum values at 2 weeks, which was earlier than in the model group (3 weeks). Conclusion: Apo J served as an acute phase reactant after balloon injury in rat carotid arteries. Rosuvastatin may reduce the neointima formation through up-regulation of Apo J. Our results suggest that Apo J exerts a protective role in the restenosis after balloon-injury in rats.
Resumo Fundamento: A reestenose após intervenção coronária percutânea (ICP) após doença coronariana continua um problema não solucionado. Estudos relataram que os níveis de clusterina (CLU), também chamada de apolipoproteína (Apo) J, encontram-se elevados na progressão da reestenose pós-angioplastia e na aterosclerose. Contudo, seu papel na hihperplasia neointimal ainda é controverso. Objetivo: Elucidar o papel da Apo J na hiperplasia neointimal na artéria carótida utilizando um modelo experimental com ratos in vivo, com e sem intervenção com rosuvastatina. Métodos: ratos Wistar machos foram divididos aleatoriamente em três grupos - grupo controle (n = 20), grupo modelo (n = 20), e grupo intervenção com estatina (n = 32). Os ratos no grupo intervenção receberam 10 mg/kg de rosuvastatina. Um cateter Fogarty 2 F foi introduzido para induzir lesão vascular. A formação de neoíntima foi analisada 1, 2, 3 e 4 semanas após lesão com balão. Concentrações de Apo J foram medidas por PCR em tempo real, imuno-histoquímica e western blotting. Resultados: A razão área íntima/média (I/M) aumentou após a lesão com balão e atingiu o valor máximo 4 semanas pós-lesão no grupo modelo; observou-se um pequeno aumento na I/M na semana 2, que cessou após a administração de rosuvastatina. Os níveis de mRNA e proteína da Apo J nas artérias carótidas aumentaram significativamente após administração de rosuvastatina em comparação ao grupo modelo, atingindo o máximo na semana 2, mais cedo em comparação ao grupo modelo (semana 3). Conclusão: A Apo J atuou como reagente de fase aguda após lesão com balão nas artérias carótidas de ratos. A rosuvastatina pode reduzir a formação de neoíntoma por aumento de Apo J. Nossos resultados sugerem que a Apo J exerce um papel protetor na reestenose após lesão com balão em ratos.
Subject(s)
Animals , Male , Angioplasty, Balloon, Coronary/adverse effects , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Carotid Artery Injuries/drug therapy , Coronary Restenosis/drug therapy , Clusterin/drug effects , Anticholesteremic Agents/pharmacology , Time Factors , Enzyme-Linked Immunosorbent Assay , Immunohistochemistry , Carotid Arteries/drug effects , Carotid Arteries/pathology , Random Allocation , Blotting, Western , Reproducibility of Results , Treatment Outcome , Tunica Media/drug effects , Tunica Media/pathology , Tunica Intima/drug effects , Tunica Intima/pathology , Rats, Wistar , Protective Agents/pharmacology , Carotid Artery Injuries/etiology , Carotid Artery Injuries/pathology , Coronary Restenosis/etiology , Coronary Restenosis/pathology , Clusterin/analysis , Real-Time Polymerase Chain Reaction , Rosuvastatin Calcium/pharmacologyABSTRACT
Neointimal proliferation after vascular injury is a key mechanism of restenosis, a major cause of percutaneous transluminal angioplasty failure and artery bypass occlusion. Emodin, an anthraquinone with multiple physiological activities, has been reported to inhibit proliferation of vascular smooth muscle cells (VSMCs) that might cause intimal arterial thickening. Thus, in this study, we established a rat model of balloon-injured carotid artery and investigated the therapeutic effect of emodin and its underlying mechanism. Intimal thickness was analyzed by hematoxylin and eosin staining. Expression of Wnt4, dvl-1, beta-catenin and collagen was determined by immunohistochemistry and/or western blotting. The proliferation of VSMC was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and electron microscopy. MicroRNA levels were quantified by real-time quantitative PCR. Emodin relieved injury-induced artery intimal thickness. Results of western blots and immunohistochemistry showed that emodin suppressed expression of signaling molecules Wnt4/Dvl-1/beta-catenin as well as collagen protein in the injured artery. In addition, emodin enhanced expression of an artery injury-related microRNA, miR-126. In vitro, MTT assay showed that emodin suppressed angiotensin II (AngII)-induced proliferation of VSMCs. Emodin reversed AngII-induced activation of Wnt4/Dvl-1/beta-catenin signaling by increasing expression of miR-126 that was strongly supported by transfection of mimic or inhibitor for miR-126. Emodin prevents intimal thickening via Wnt4/Dvl-1/beta-catenin signaling pathway mediated by miR-126 in balloon-injured carotid artery of rats.
Subject(s)
Animals , Male , Rats , Adaptor Proteins, Signal Transducing/metabolism , Carotid Arteries/drug effects , Carotid Artery Injuries/drug therapy , Cell Proliferation/drug effects , Emodin/therapeutic use , MicroRNAs/metabolism , Phosphoproteins/metabolism , Rats, Sprague-Dawley , Signal Transduction/drug effects , Tunica Intima/drug effects , Wnt4 Protein/metabolism , beta Catenin/metabolismABSTRACT
Durante a década passada, o reconhecimento e tratamento do traumatismo cerebrovascular contuso, sofreu importante evolução. Este tipo de ferimento era considerado como ocorrência rara, mas atualmente o quadro é diagnosticado em cerca de 1% dos pacientes. O reconhecimento da existência de um período clínico silencioso permite uma seleção angiográfica baseada no mecanismo de trauma e na sistematização dos ferimentos dos pacientes. A avaliação sistemática e a suspeita diagnóstica precoce destes pacientes tem resultado em rápido confirmação durante a fase assintomática, permitindo a instauração de tratamento cuja meta é impedir o desenvolvimento de seqüelas neurológicas. Embora o tratamento ideal, antitrombótico, ainda precise ser determinado, o uso de agentes antiplaquetários ou anticoagulantes reduz a incidência de lesões cerebrovasculares relacionada a fenômenos tromboembolíticos. O traumatismo cerebrovascular contuso é raro, porém devastador. A seleção angiográfica apropriada em pacientes de alto risco deve ser realizada e o tratamento deve ser imediatamente iniciado para impedir eventos neurológicos isquêmicos.