Michel Pucéat (I-Stem, Inserm/AFM/UEVE, Evry) presented his team’s most recent advances in the use of human embryonic cells in the treatment of myocardial infarction. Since their work on the rat (Stem Cells, June 2007), the researchers have made progress by experimenting their therapeutic strategy on a model far closer to man – monkeys, presenting with a slight myocardial infarction. Also, they were able to note the differentiation of embryonic cells into cardiac cells (cardiomyocytes) and above all the total absence of any tumoral development in the heart or in other organs. A new step has been taken with the use of embryonic cells in heart therapy.

Angelo Parini (Inserm U858, Toulouse) presented his team’s work using mesenchymatous stem cells. These adult stem cells are at the origin of bone, cartilage and fatty tissue but can also produce other cell types, in particular skeletal or cardiac muscle cells. After noting that – following transplantation into the heart or kidney of animal models more than 80% of the transplanted cells died due to oxidative stress – the researchers endeavoured to increase their viability. They added melatonin (known for its strong anti-oxidative properties and widely used in humans) to the mesenchymatous cells in culture, thus protecting them from oxidative stress. Once transplanted into the myocardial infarcted rat hearts, these melatonin-treated cells lived longer and led to an improvement of the cardiac function.