Tumor necrosis factor-?-induced microvascular endothelial cell hyperpermeability: role of intrinsic apoptotic signaling

• Autores: Devendra A. Sawant, Rickesha L. Wilson, Binu Tharakan, Hayden W. Stagg, Felicia A. Hunter, Ed W. Childs
• Localización: Journal of physiology and biochemistry, ISSN-e 1877-8755, ISSN 1138-7548, Vol. 70, Nº. 4, 2014, págs. 971-980
• Idioma: inglés
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• Resumen

  • Tumor necrosis factor-? (TNF-?), a pro-apoptotic cytokine, is involved in vascular hyperpermeability, tissue edema, and inflammation. We hypothesized that TNF-? induces microvascular hyperpermeability through the mitochondria-mediated intrinsic apoptotic signaling pathway. Rat lung microvascular endothelial cells grown on Transwell inserts, chamber slides, or dishes were treated with recombinant TNF-? (10 ng/ml) in the presence or absence of a caspase-3 inhibitor, Z-DEVD-FMK (100 ?M). Fluorescein isothiocyanate (FITC)-albumin (5 mg/ml) was used as a marker of monolayer permeability. Mitochondrial reactive oxygen species (ROS) was determined using dihydrorhodamine 123 and mitochondrial transmembrane potential using JC-1. The adherens junction integrity and actin cytoskeletal organization were studied using ?-catenin immunofluorescence and rhodamine phalloidin, respectively. Caspase-3 activity was measured fluorometrically. The pretreatment with Z-DEVD-FMK (100 ?M) attenuated TNF-?-induced (10 ng/ml) disruption of the adherens junctions, actin stress fiber formation, increased caspase-3 activity, and monolayer hyperpermeability (p < 0.05). TNF-? (10 ng/ml) treatment resulted in increased mitochondrial ROS formation and decreased mitochondrial transmembrane potential. Intrinsic apoptotic signaling-mediated caspase-3 activation plays an important role in regulating TNF-?-induced endothelial cell hyperpermeability.