BPA disrupts the cardioprotection by 17β-oestradiol against ischemia/reperfusion injury in isolated guinea pig hearts

Bisphenol A (BPA) is an environmental oestrogen or xenoestrogen (XEs). XEs represent a health risk due to their potential for endocrine disruption and ability to mimic estrogenic activity. The effects of BPA on isolated hearts under normal and ischemia/reperfusion (I/R) conditions were investigated for the first time, with a focus on the effects of BPA and 17 beta-oestradiol (E-2) co-administration on I/R injury. Our results indicated that BPA at 10(-7) M and 10(-5) M did not significantly affect heart rate (HR), coronary flow (CF), lactate dehydrogenase (LDH) or creatine kinase (CK) release in normal or I/R isolated hearts within the 90 min. However, E-2 exerted a protective effect against I/R injury, whereas, BPA inhibited the cardio-protective effects of E-2 on HR, CF, and LDH and CK release. Furthermore, BPA in combination with E-2 aggravated I/R injury by increasing infarct size and causing a more severe ultrastructural disruption as compared to treatment with E-2 alone. Based on our results, we conclude that BPA inhibits the cardio-protective effects of E-2 on I/R-injured hearts, despite not significantly affecting normal or I/R isolated hearts.