POTENTIAL CARDIOPROTECTIVE EFFECT OF GENIPIN VIA CYCLOOXIDASE 2 SUPPRESSION AND P53 SIGNAL PATHWAY ATTENUATION IN INDUCED MYOCARDIAL INFARCTION IN RATS.

Background and aims: Genipin, an iridoid derived from geniposide by β-glucosidase hydrolysis, has shown potential benefit in the treatment of heart function insufficiency despite its unclear therapeutic mechanism. This study aimed to investigate the primary cardioprotective mechanism of genipin. We hypothesized that genipin demonstrated the antiapoptosis and anti-inflammation for cardiac protection by inhibiting the cyclooxidase 2 (COX2)-prostaglandin D2 (PGD2) and murine double minute 2 (MDM2)-p53 pathways. Methods: The normal Sprague-Dawley rats were made into myocardial infarction models by conventional methods. Animals were treated with genipin for 5 weeks after myocardial infarction (MI). Morphometric and hemodynamic measurements were performed 5 weeks post-MI. Biological and molecular experiments were performed after the termination. Results: Both morphometry and hemodynamics in systole and diastole were significantly impaired in the model group but restored close to basal level after treatment with genipin. Genipin also restored the post-MI upregulated expressions of cytochrome c, p53, COX2, and PGD2 and downregulated expression of MDM2 to the approximate baseline. Genipin inhibited apoptotic and inflammatory pathways to prevent post-MI structure-function remodeling. Conclusions: This study showed the cardioprotective mechanism of genipin and implied its potential clinical application for the treatment of ischemic heart failure.