Abstract 215: Intralipid Protects The Heart In Late Pregnancy Against Ischemia Reperfusion Injury Via Stat3 Signaling Pathway
We have recently reported that the hearts of late pregnant (LP) mice are more prone to ischemia/reperfusion (I/R) injury compared to non pregnant mice. We also found that intralipid, a fat emulsion commonly used for parenteral nutrition, protects the male rodent heart against I/R injury if administrated during reperfusion. The activation of the survivor activating factor enhancement (SAFE) pathway, which includes the activation of the transcription factor signal transducer and activator of transcription-3 (STAT3), has recently been highlighted in cardioprotection. Here we explored the therapeutic potential of intralipid in the protection of LP mouse hearts against I/R injury as well as the involvement of STAT3 signaling pathway. Isolated LP mouse hearts were subjected to 20 min ischemia followed by reperfusion with i) Krebs Henseleit buffer (CTRL group), ii) 1% intralipid (ITLD group) or iii) ITLD+STAT3 inhibitor Stattic (20 µM, Stattic group). The duration of reperfusion was 40 min for heart functional measurements and infarct size assessment. Postischemic administration of intralipid significantly improved the cardiac function of LP mice after ischemia. The rate pressure product (RPP) at the end of reperfusion was improved from 1617±287mmHg*beats/min (n=6) in CTRL to 11556±784 mmHg*beats/min (n=5) in the ITLD group. The infarct size was also significantly reduced by postischemic administration of intralipid to 17±2% (n=5) from 59±5%(n=6) in CTRL (p<0.01). A specific inhibitor of STAT3, Stattic, fully abolished, intralipid-induced cardioprotection, as the RPP at the end of reperfusion in the Stattic group (1345±559, n=3) was similar to CTRL group, and significantly lower compared with ITLD group. Furthermore, the infarct size in the Stattic group was markedly higher compared with ITLD group (48±99% (n=3) vs. 17±2%(n=5) in ITLD group, p<0.01). In conclusion, intralipid protects the late pregnant heart against I/R injury via the STAT3 signaling pathway.
- © 2013 by American Heart Association, Inc.