Cyclosporine A–protection against microvascular hyperpermeability is calcineurin independent

• Published in: The American journal of surgery 2010-04, Vol.199 (4), p.542-548
• Main Authors: Childs, Ed W., M.D, Tharakan, Binu, Ph.D, Nurudeen, Suliat, B.S, Delmas, Thomas L., B.S, Hellman, Joseph, B.S, Christie, Tasheika, B.S, Hunter, Felicia A., B.S, Smythe, W. Roy, M.D
• Format: Article
• Language: English
• Subjects: Albumin; Animals; Apoptosis; Apoptosis - drug effects; Apoptosis Regulatory Proteins; Attenuation; BAK protein; Calcineurin; Calcineurin - metabolism; Capillary Permeability - drug effects; Carrier Proteins - metabolism; Caspase; Caspase Inhibitors; Caspase-3; Cell death; Cyclosporine - pharmacology; Cyclosporins; Cytochrome; Cytochrome c; Cytochromes c - metabolism; Endothelium, Vascular - cytology; Endothelium, Vascular - drug effects; Enzyme-linked immunosorbent assay; Fluorescein; Fluorescein isothiocyanate; Iodides; Ischemia; Kinases; Laboratories; Lung - blood supply; Membrane potential; Microcirculation; Microvasculature; Mitochondria; Mitochondria - metabolism; Monolayers; Peptides; Permeability; Phenols; Proteins; Rats; Rodents; Signal Transduction - drug effects; Studies; Surgery; Vascular permeability; “Intrinsic” apoptotic cascade
• ISSN: 0002-9610; 1879-1883
• DOI: 10.1016/j.amjsurg.2009.11.002

Abstract Background Mitochondria-mediated apoptotic signaling contributes to microvascular hyperpermeability. We hypothesized that cyclosporine A (CsA), which protects mitochondrial transition pores, would attenuate hyperpermeability independent of its calcineurin inhibitory property. Methods Hyperpermeability was induced in microvascular endothelial cell monolayers using proapoptotic BAK or active caspase-3 after CsA or a specific calcineurin inhibitor, calcineurin autoinhibitory peptide (CIP), treatment. Permeability was measured based on fluorescein isothiocyanate–albumin flux across the monolayers. Mitochondrial transmembrane potential (MTP) was determined using 5,5′,6,6′-tetrachoro-1,1′,3,3′-tetraethylbenzimidazolyl carbocyanine iodide. Mitochondrial release of cytochrome c was measured using an enzyme-linked immunosorbent assay and caspase-3 activity fluorometrically. Results CsA-attenuated (10 nmol/L) but not CIP-attenuated (100 μmol/L) BAK induced hyperpermeability ( P < .05), CsA- but not CIP-attenuated BAK induced a decrease in MTP and an increase in cytochrome c levels and caspase-3 activity ( P < .05). CsA and CIP were ineffective against caspase-3–induced hyperpermeability. Conclusions CsA attenuated hyperpermeability by protecting MTP, thus preventing mitochondria-mediated apoptotic signaling. The protective effect of CsA is independent of calcineurin inhibition.