Uterine cells are recruited to the infarcted heart and improve cardiac outcomes in female rats

We evaluated the hypothesis that uterine cells home to the heart after injury and improve cardiac outcomes. Premenopausal women have fewer cardiovascular complications than age-matched men, but the mechanisms responsible for this protection have not been conclusively identified. Hysterectomy was performed in young female rats (leaving the ovaries intact), and 7 days later the left coronary artery was ligated to produce a myocardial infarction (MI). Cardiac function at 28 days post-MI was measured using echocardiography. Fractional shortening was best in non-hysterectomized (non-Hx) females and lower in both Hx females and males. Uteri were then removed from GFP rats and heterotopically transplanted into non-GFP recipients to investigate homing of uterine cells to the infarcted myocardium. Seven days later, the uterine transplant recipients underwent coronary ligation. GFP(+) cells were found in the recipient hearts 7 days after MI and persisted for 6 months. Confocal analysis showed that homed uterine cells were located around blood vessels, suggesting their involvement in neovascularization. We then evaluated uterine cell transplantation by intravenously injecting GFP(+) uterine cells into Hx females immediately after MI. These GFP(+) cells were found to home to the injured myocardium, stimulate angiogenesis, improve cardiac function, and increase survival. This study demonstrates that uterine cells can home to the injured myocardium, enhance tissue repair, and prevent cardiac dysfunction. Uterine cells may play a role in the prevention of cardiovascular complications in females.