Pharmacological inhibition of 11βhydroxysteroid dehydrogenase type 1 after myocardial infarction targets extracellular matrix processing and preserves cardiac function in a translational mini-pig model

Background and PurposePlasma glucocorticoids (GCs) increase acutely after myocardial infarction (MI), thereafter tissue levels are amplified selectively within cells expressing 11{beta}Hydroxysteroid Dehydrogenase type 1 (11{beta}HSD1) that regenerates active GCs from circulating metabolites. GCs initially protect cardiomyocytes and prevent excessive inflammation after MI but can also suppress subsequent wound repair leading to functional decline. The present study aimed to investigate the potential of pharmacological 11{beta}HSD1 inhibition after MI to prevent deterioration of cardiac function and its impact on wound repair. Experimental ApproachAdult female Gottingen mini-pigs underwent percutaneous balloon MI/reperfusion and were randomised to receive either oral 11{beta}HSD1 inhibitor AZD8329 (n=11), or vehicle (n=9), from 2 until 27 days later, with concurrent administration of clinically relevant therapeutic intervention (anti-platelet, statin and ACE inhibitor). Key ResultsAZD8329 treatment increased plasma accumulation of cortisone substrate consistent with successful 11{beta}HSD1 inhibition. Gadolinium-enhanced MRI showed equivalent infarct size in both groups prior to commencing treatment. 28 days after MI cardiac function and LV area were preserved in the AZD8329 treated group relative to vehicle. There was no impact of 11{beta}HSD1 inhibitor on neovascularisation or infarct area. Mass spectrometry imaging revealed AZD8329 binding to the healing infarct and altered regulation of extracellular matrix (ECM) processing was highlighted by birefringence microscopy and proteomic analysis. Conclusions and ImplicationsPharmacological inhibition of 11{beta}HSD1 after MI prevents deterioration of cardiac function and detrimental remodelling. 11{beta}HSD1 inhibitors have safely reached phase 2 clinical trials in diabetes and dementia and could be repurposed as an addition to standard care after MI to prevent the development of heart failure. Bullet Point Summary What is already known?O_LIGCs are released from the adrenal gland after MI, but also regenerated within the heart from circulating precursors by the enzyme 11{beta}HSD1 in cardiomyocytes, fibroblasts and macrophages. C_LIO_LIGenetic suppression of Hsd11b1 expression in the mouse promotes neovascularisation, prevents infarct expansion during infarct repair after MI and the development of heart failure. C_LI What does this study add?O_LIOral pharmacological inhibition of 11{beta}HSD1 after MI/reperfusion in a translational mini-pig model of MI receiving concurrent clinically relevant therapy prevents cardiac functional deterioration and adverse ventricular remodelling over the following 4 weeks. C_LIO_LIMass spectrometry imaging reveals target engagement of the 11{beta}HSD1i in the repairing infarct. C_LIO_LIThe mechanism is independent of neovascularisation but does involve modification of extracellular matrix remodelling during repair and scar formation. C_LI What is the clinical significance?O_LITissue 11{beta}HSD1 expression is increased in aging when the risk of MI is higher. C_LIO_LIPharmacological inhibitors of 11{beta}HSD1 have safely reached phase 2 clinical trials for dementia and metabolic disease and could be repurposed for use post-MI to prevent the development of heart failure. C_LI