Sex- and age-specific acute beneficial effects of an estrogen receptor agonist added to a cardioplegic solution in adult and aging mouse hearts

Abstract

This study investigated effects of G1, a G-protein estrogen receptor (GPER) agonist, in a Langendorff-perfused mouse heart model of cardioplegia in adult and aged mice of both sexes. The recovery of cardiac function using St. Thomas’ Hospital cardioplegic solution No. 2 (STH2), prior to ischemia/reperfusion insult was better in adult female hearts compared to adult males. By contrast, hearts from old mice of both sexes recovered similarly or recovery was even better in males. However, the extent of recovery with STH2 was sub-optimal. When G1 was incorporated in STH2 results showed enhanced cardiac recovery in adult female mouse hearts but not in males. This protection with G1 was, however, observed in old mouse hearts from both sexes. The effect of G1 was also blocked by the GPER antagonist, G15. Together these findings suggest that addition of G1 in STH2 is a useful strategy to improve outcomes of cardiac surgery.