RESUMO
Effects of ischaemic preconditioning (IP) on the mobilisation and recruitment of haematopoietic (HSCs) and mesenchymal stem (MSC) cells were determined in porcine coronary occlusion/reperfusion. Thirty-three pigs underwent percutaneous occlusion of the left anterior descending coronary artery (LAD) for 90 minutes (min), followed by 120 min reperfusion. IP was performed in 16 of the 33 pigs by two cycles of 5 min balloon occlusion/reperfusion prior to the 90 min occlusion (group IP vs. group C). Peripheral blood and myocardial tissue concentration of bone marrow origin HSCs (characterised by coexpression of CD31+, CD90+, CD45+) and MSCs (characterised by coexpression of CD44+, CD90+, CD45-) were measured by flow cytometry in the early phase of IP. Plasma/serum levels of stem cell mobilisation factors (stromal cell-derived factor-1a [SDF-1a], vascular endothelial growth factor [VEGF], tumour necrosis factor a[TNF-a] and interleukin-8 [IL-8]) were measured. IP led to a significant increase in circulating HSCs as compared with the group C (475 +/- 233 vs. 281 +/- 264 /ml, p=0.032) in the early phase of IP. In contrast, a rapid and prolonged decrease in level of circulating MSCs was observed in group IP as compared with group C (19 +/- 12 vs. 32 +/- 17 /ml, p=0.015). The recruitment of HSCs and MSCs in infarct and border zone was significantly greater in IP group, indicating a faster homing of MSCs as compared with the rate of mobilisation. Rapid increase in VEGF, TNF-a and IL-8 levels was induced by IP, which, however, was not correlated with the levels of circulating SCs. In conclusion, IP resulted in differential mobilisation and recruitment of HSCs and MSCs in the early phase of cardioprotection.
Assuntos
Quimiotaxia , Células-Tronco Hematopoéticas/patologia , Precondicionamento Isquêmico Miocárdico , Células-Tronco Mesenquimais/patologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/patologia , Animais , Apoptose , Quimiocina CXCL12/sangue , Modelos Animais de Doenças , Citometria de Fluxo , Células-Tronco Hematopoéticas/imunologia , Células-Tronco Hematopoéticas/metabolismo , Receptores de Hialuronatos/análise , Interleucina-8/sangue , Antígenos Comuns de Leucócito/análise , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/sangue , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/sangue , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Sus scrofa , Antígenos Thy-1/análise , Fatores de Tempo , Fator de Necrose Tumoral alfa/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Função Ventricular EsquerdaRESUMO
A 64-year-old woman undergoing protected carotid artery stent placement developed acute stent thrombosis despite pretreatment with combined antiplatelet therapy. A reduced dose of recombinant tissue plasminogen activator and a half-dose bolus of abciximab were administered intra-arterially via superselective catherization followed by systemic intravenous infusion of abciximab for 12 hours. Control angiography showed complete restoration of blood flow paralleled by neurologic improvement.
