Dataset Information

Effects of exogenous recombinant APC in mouse models of ischemia reperfusion injury and of atherosclerosis.

ABSTRACT: Activated protein C (APC) is a serine protease that has both anticoagulant and cytoprotective properties. The cytoprotective effects are protease activated receptor 1 (PAR-1) and endothelial protein C receptor (EPCR) dependent and likely underlie protective effects of APC in animal models of sepsis, myocardial infarction and ischemic stroke. S360A-(A)PC, a variant (A)PC that has no catalytic activity, binds EPCR and shifts pro-inflammatory signaling of the thrombin-PAR-1 complex to anti-inflammatory signaling. In this study we investigated effects of human (h)wt-PC, hS360A-PC, hwt-APC and hS360A-APC in acute (mouse model of acute myocardial ischemia/reperfusion (I/R) injury) and chronic inflammation (apoE-/- mouse model of atherosclerosis). All h(A)PC variants significantly reduced myocardial infarct area (p<0.05) following I/R injury. IL-6 levels in heart homogenates did not differ significantly between sham, placebo and treatment groups in I/R injury. None of the h(A)PC variants decreased number and size of atherosclerotic plaques in apoE-/- mice. Only hS360A-APC slightly affected phenotype of plaques. IL-6 levels in plasma were significantly (p<0.001) decreased in hwt-APC and hS360A-PC treated mice. In the last group levels of monocyte chemotactic protein 1 (MCP-1) were significantly increased (p<0.05). In this study we show that both hwt and hS360A-(A)PC protect against acute myocardial I/R injury, which implies that protection from I/R injury is independent of the proteolytic activity of APC. However, in the chronic atherosclerosis model hwt and hS360-(A)PC had only minor effects. When the dose, species and mode of (A)PC administration will be adjusted, we believe that (A)PC will have potential to influence development of chronic inflammation as occurring during atherosclerosis as well.

SUBMITTER: Wildhagen KC

PROVIDER: S-EPMC4102480 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Effects of exogenous recombinant APC in mouse models of ischemia reperfusion injury and of atherosclerosis.

Wildhagen Karin C A A KC Schrijver Roy R Beckers Linda L ten Cate Hugo H Reutelingsperger Chris P M CP Lutgens Esther E Nicolaes Gerry A F GA

PloS one 20140717 7

Activated protein C (APC) is a serine protease that has both anticoagulant and cytoprotective properties. The cytoprotective effects are protease activated receptor 1 (PAR-1) and endothelial protein C receptor (EPCR) dependent and likely underlie protective effects of APC in animal models of sepsis, myocardial infarction and ischemic stroke. S360A-(A)PC, a variant (A)PC that has no catalytic activity, binds EPCR and shifts pro-inflammatory signaling of the thrombin-PAR-1 complex to anti-inflamma ...[more]

PMID: 25032959

Similar Datasets

Project description:BackgroundTo investigate the protective effects of exogenous spermine on renal ischemia-reperfusion injury in rats.Methods(I) Different doses of spermine were injected into rats to determine the safe dose on the kidneys. Kidney toxicity was assessed by hematoxylin and eosin (HE) staining of kidney tissue and enzyme-linked immunosorbent assay (ELISA) detection of neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule 1 (KIM-1) in the venous blood. (II) A rat model of renal ischemia-reperfusion injury was established. Different doses of spermine were injected into the rats through the tail vein 30 minutes before and 3 days after the establishment of the model. Blood samples and kidney tissues were collected and renal injury was assessed via HE staining of the renal tissue, detection of apoptosis using the TUNEL assay, and detection of NGAL and KIM-1 in blood samples using ELISA. (III) Human HK-2 renal tubular epithelial cells were cultured under hypoxia/reoxygenation conditions. To evaluate the protective effects of spermine, apoptosis was assessed by flow cytometry and TUNEL assay. The mechanisms underlying the effects of spermine were studied using Western blot analyses.ResultsAt spermine concentrations below 200 µM (2 mL/kg body weight), no significant damage to the kidney was observed by HE staining, and there was no significant difference in NGAL and KIM-1 levels between rats treated with spermine and control rats (P<0.05). At spermine doses below 200 µM, HE staining showed that the degree of renal ischemia-reperfusion injury was gradually alleviated with increasing doses of spermine. TUNEL assays demonstrated that spermine reduced the apoptosis of renal tissue, and increasing doses of spermine gradually decreased the levels of NGAL and KIM-1 in the blood compared with the control group (P<0.05). Western blot analysis revealed that spermine increased the expression of pro-caspase9, phosphorylated protein kinase B (p-Akt), hypoxia-inducible factor 1 alpha (HIF-1α), B cell lymphoma 2 (Bcl-2), and Bcl2 interacting protein 3 (BNIP3), and decreased the expression of cleaved caspase-3, Bax and cytochrome C compared to control cells.ConclusionsExogenous spermine exerted a protective effect on renal ischemia-reperfusion injury in rats by inhibiting the apoptosis of renal tubular epithelial cells.

Project description:Timely reperfusion after a myocardial infarction is necessary to salvage the ischemic region; however, reperfusion itself is also a major contributor to the final tissue damage. Currently, there is no clinically relevant therapy available to reduce ischemia-reperfusion injury (IRI). While many drugs have shown promise in reducing IRI in preclinical studies, none of these drugs have demonstrated benefit in large clinical trials. Part of this failure to translate therapies can be attributed to the reliance on small animal models for preclinical studies. While animal models encapsulate the complexity of the systemic in vivo environment, they do not fully recapitulate human cardiac physiology. Furthermore, it is difficult to uncouple the various interacting pathways in vivo. In contrast, in vitro models using isolated cardiomyocytes allow studies of the direct effect of therapeutics on cardiomyocytes. External factors can be controlled in simulated ischemia-reperfusion to allow for better understanding of the mechanisms that drive IRI. In addition, the availability of cardiomyocytes derived from human induced pluripotent stem cells (hIPS-CMs) offers the opportunity to recapitulate human physiology in vitro. Unfortunately, hIPS-CMs are relatively fetal in phenotype, and are more resistant to hypoxia than the mature cells. Tissue engineering platforms can promote cardiomyocyte maturation for a more predictive physiologic response. These platforms can further be improved upon to account for the heterogenous patient populations seen in the clinical settings and facilitate the translation of therapies. Thereby, the current preclinical studies can be further developed using currently available tools to achieve better predictive drug testing and understanding of IRI. In this article, we discuss the state of the art of in vitro modeling of IRI, propose the roles for tissue engineering in studying IRI and testing the new therapeutic modalities, and how the human tissue models can facilitate translation into the clinic.

Dataset Information

Effects of exogenous recombinant APC in mouse models of ischemia reperfusion injury and of atherosclerosis.

Publications

Effects of exogenous recombinant APC in mouse models of ischemia reperfusion injury and of atherosclerosis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets