Plasma from human volunteers subjected to remote ischemic preconditioning protects human endothelial cells from hypoxia–induced cell damage

• Published in: Basic research in cardiology 2015-03, Vol.110 (2), p.17-17, Article 17
• Main Authors: Weber, Nina C., Riedemann, Isabelle, Smit, Kirsten F., Zitta, Karina, van de Vondervoort, Djai, Zuurbier, Coert J., Hollmann, Markus W., Preckel, Benedikt, Albrecht, Martin
• Format: Article
• Language: English
• Subjects: Adult; Blotting, Western; Cardiology; Cell Hypoxia - physiology; Endothelial Cells - pathology; Enzyme-Linked Immunosorbent Assay; Humans; Ischemic Preconditioning, Myocardial - methods; Male; Medicine; Medicine & Public Health; Original Contribution; Plasma - chemistry; Plasma - physiology; Reperfusion Injury - prevention & control; Young Adult
• ISSN: 0300-8428; 1435-1803
• DOI: 10.1007/s00395-015-0474-9

Short repeated cycles of peripheral ischemia/reperfusion (I/R) can protect distant organs from subsequent prolonged I/R injury; a phenomenon known as remote ischemic preconditioning (RIPC). A RIPC-mediated release of humoral factors might play a key role in this protection and vascular endothelial cells are potential targets for these secreted factors. In the present study, RIPC-plasma obtained from healthy male volunteers was tested for its ability to protect human umbilical endothelial cells (HUVEC) from hypoxia–induced cell damage. 10 healthy male volunteers were subjected to a RIPC-protocol consisting of 4 × 5 min inflation/deflation of a blood pressure cuff located at the upper arm. Plasma was collected before ( T 0; control), directly after ( T 1) and 1 h after ( T 2) the RIPC procedure. HUVEC were subjected to 24 h hypoxia damage and simultaneously incubated with 5 % of the respective RIPC-plasma. Cell damage was evaluated by lactate dehydrogenase (LDH)-measurements. Western blot experiments of hypoxia inducible factor 1 alpha (HIF1alpha), phosphorylated signal transducer and activator of transcription 5 (STAT5), protein kinase B (AKT) and extracellular signal-related kinase 1/2 (ERK-1/2) were performed. Furthermore, the concentrations of hVEGF were evaluated in the RIPC-plasma by sandwich ELISA. Hypoxia–induced cell damage was significantly reduced by plasma T 1 ( p  = 0.02 vs T 0). The protective effect of plasma T 1 was accompanied by an augmentation of the intracellular HIF1alpha ( p  = 0.01 vs T 0) and increased phosphorylation of ERK-1/2 ( p  = 0.03 vs T 0). Phosphorylation of AKT and STAT5 remained unchanged. Analysis of the protective RIPC-plasma T 1 showed significantly reduced levels of hVEGF ( p  = 0.01 vs T 0). RIPC plasma protects endothelial cells from hypoxia–induced cell damage and humoral mediators as well as intracellular HIF1alpha may be involved.