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Updated: Jun 27, 2026
A Murine Closed-chest Model of Myocardial Ischemia and Reperfusion
Published on: July 17, 2012
Active site inhibited factor VIIa attenuates myocardial ischemia/reperfusion injury in mice
S T B G Loubele1, C A Spek, P Leenders
1Department of Internal Medicine, Laboratory for Clinical Thrombosis and Haemostasis, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands. sarah.loubele@bioch.unimaas.nl
Background:
Inhibition of specific coagulation pathways such as the factor VIIa-tissue factor complex has been shown to attenuate ischemia/reperfusion (I/R) injury, but the cellular mechanisms have not been explored.
Objectives:
To determine the cellular mechanisms involved in the working mechanism of active site inhibited factor VIIa (ASIS) in the protection against myocardial I/R injury.
Methods:
We investigated the effects of a specific mouse recombinant in a mouse model of myocardial I/R injury. One hour of ischemia was followed by 2, 6 or 24 h of reperfusion. Mouse ASIS or placebo was administered before and after induction of reperfusion.
Results:
ASIS administration reduced myocardial I/R injury by more than 40% at three reperfusion times. Multiplex ligation dependent probe amplification (MLPA) analysis showed reduced mRNA expression in the ischemic myocardium of CD14, TLR-4, interleukin-1 (IL-1) receptor-associated kinase (IRAK) and IkappaBalpha upon ASIS administration, indicative of inhibition of toll-like receptor-4 (TLR-4) and subsequent nuclear factor-kappaB (NF-kappaB) mediated cell signaling. Levels of nuclear activated NF-kappaB and proteins influenced by the NF-kappaB pathway including tissue factor (TF) and IL-6 that were increased after I/R, were attenuated upon ASIS administration. After 6 and 24 h of reperfusion, neutrophil infiltration into the area of infarction was decreased upon ASIS administration. There was, however, no evidence of an effect of ASIS on apoptosis (Tunel staining and MLPA analysis).
Conclusions:
We conclude that the diminished amount of myocardial I/R injury after ASIS administration is primarily due to attenuated inflammation-related lethal I/R injury, probably mediated through the NF-kappaB mechanism.
Insights
Active site inhibited factor VIIa (ASIS) significantly reduces myocardial ischemia/reperfusion (I/R) injury by over 40%. This protection is linked to reduced inflammation via the nuclear factor-kappaB (NF-kappaB) pathway, not apoptosis.
Area of Science:
- Cardiovascular Research
- Coagulation and Thrombosis
- Inflammation and Immunology
Background:
- Ischemia/reperfusion (I/R) injury affects the heart, and inhibiting coagulation pathways like factor VIIa-tissue factor can help.
- The precise cellular mechanisms behind this protective effect remain largely unexplored.
Purpose of the Study:
- To elucidate the cellular mechanisms by which active site inhibited factor VIIa (ASIS) protects against myocardial I/R injury.
- To investigate the role of specific molecular pathways in ASIS-mediated cardioprotection.
Main Methods:
- A mouse model of myocardial I/R injury was utilized, with ischemia followed by 2, 6, or 24 hours of reperfusion.
- Active site inhibited factor VIIa (ASIS) or placebo was administered before and after reperfusion induction.
- Multiplex ligation dependent probe amplification (MLPA) and protein analysis were used to assess gene and protein expression.
Main Results:
- ASIS administration reduced myocardial I/R injury by over 40% across all reperfusion times.
- ASIS treatment attenuated mRNA expression of CD14, TLR-4, IRAK, and IkappaBalpha, indicating inhibition of toll-like receptor-4 (TLR-4) and nuclear factor-kappaB (NF-kappaB) signaling.
- Activated NF-kappaB levels and downstream proteins like tissue factor (TF) and IL-6 were reduced by ASIS. Neutrophil infiltration also decreased.
- No significant effect of ASIS on apoptosis was observed.
Conclusions:
- The cardioprotective effects of ASIS against I/R injury are primarily attributed to the attenuation of inflammation.
- The nuclear factor-kappaB (NF-kappaB) pathway appears to be a key mediator of ASIS-induced anti-inflammatory effects in myocardial I/R injury.
- ASIS offers a promising therapeutic strategy for mitigating inflammation-driven myocardial I/R damage.
