Shz-1 is a Shz that activates cardiac differentiation, inducing the expression of early cardiac genes in mouse pluripotent and embryonic stem cells in vitro at low micromolar concentrations. In addition, Shz-1 drives differentiation of human peripheral blood mononuclear cells, mobilized by granule colony-stimulating factor, toward a cardiac phenotype. These Shz-1 treated cells enhance myocardial regenerative repair in cryo-injured rat heart.