The effects had never been studied yet on a lung model for large mammals. Our data showed dose-dependent effects of CsA on gas exchanges, but also on pulmonary hemodynamics, and possibly an aggravation of the IRI due to high doses of CsA. These results constitute an important step toward the use of CsA on humans to reduce lung IRI and consequently, primary graft dysfunction. Within a few years, the EVLP technique has become a reference for the evaluation of lung grafts. Its interest has been demonstrated PLX4032 purchase on animal
lung preparations, especially on pig [43] and human lungs [12]. This technique can be seen as bench test for lung function, allowing for the assessment of new therapies suppose to limit IRI. Gas exchange capacities and total pulmonary arterial resistance are more commonly studied physiopathological parameters. We also measured other hemodynamics (Pcap,
longitudinal pulmonary resistance) and markers (AFC, RAGE, cytokines, lung permeability) that have showed their pertinence in the evaluation of lung IRI [5, 7]. It has been hypothesized that IRI is mostly related to mitochondrial death as a consequence of MPTP opening. Located in the inner mitochondrial membrane, the MPTP remains unremarkable under normal physiological conditions. Stress can lead to its opening, resulting in the swelling of the matrix due to osmotic forces. It then induces further failure of the mitochondrial outer membrane and the release of the cytosol pro-apoptotic factors [19]. The inhibition of PXD101 clinical trial the opening of MPTP is thought to be the main pathway for CsA action. Several in vitro and in vivo animal models showed CsA interests in pre and post-conditioning for the
prevention of IRI on different organs such as heart, kidney, and liver [19, 20, 45, 50]. In humans, CsA administered just before coronary reperfusion (post-conditioning) has been proven to be an efficient way to reduce the size of myocardial infarction [33]. However, few studies have been published on CsA effects on lung IRI. In vitro studies on post hypoxia-reoxygenation injuries showed that alveolar macrophages pretreated by CsA secreted less chemokines than Tideglusib controls [30]. Moreover, endothelial cells incubated with CsA selectively reduced pro-inflammatory mediator secretion of NFκB and EGR-1 [15]. Nevertheless, some of the pathways involved in IRI can be activated by CsA, such as the metalloproteinase and the TLR [1, 28, 41]. Such insights can explain the increased levels of pro-inflammatory cytokines we measured in our experiments with high doses of CsA (30 μM). In an in vivo ischemic lung model, Krishnadasan et al. showed that rats pre-conditioned with CsA displayed less tissue myeloperoxidase content, leukocyte accumulation, and vascular permeability [25].