TGFβ signalling has been shown to be important at an early stage in cardiac development, with most previous investigations focussing on the role during formation of the cardiac cushions. These cushions, which develop between embryonic day E9.5 and E11.5 in the mouse, are essential precursors of the mature valves, and intimately involved in septation. It is well known that TGFβ signalling promotes endothelial to mesenchymal transition, and subsequent migration of mesenchymal cells to the cardiac jelly. ITD-1 is the first selective TGFβ inhibitor.

In vitro: ITD-1 has been used to evaluate TGFβ involvement in mesoderm formation and cardiopoietic differentiation, which occur sequentially during early development, indicating an essential role in both processes in ESC cultures. ITD-1 selectively enhanced the uncommitted mesoderm differentiation to cardiomyocytes, but not to vascular smooth muscle and endothelial cells. In summary, ITD-1 is the first selective TGFβ inhibitor and reveals an unexpected role for TGFβ signaling in controlling the differentiation of cardiomyocyte from multipotent cardiovascular precursors [1].

In vivo: So far, ITD-1 has not been subjected to conduct animal in vivo study.

Clinical trial: Up to now, ITD-1 is still in the preclinical development stage.

Reference:
[1] Willems E, Cabral-Teixeira J, Schade D, Cai W, Reeves P, Bushway PJ, Lanier M, Walsh C, Kirchhausen T, Izpisua Belmonte JC, Cashman J, Mercola M. Small molecule-mediated TGF-β type II receptor degradation promotes cardiomyogenesis in embryonic stem cells. Cell Stem Cell. 2012 Aug 3;11(2):242-52.