Adenovirus-Mediated Overexpression of O -GlcNAcase Improves Contractile Function in the Diabetic Heart

Abstract
To examine whether excessive protein O -GlcNAcylation plays a role in the dysfunction of the diabetic heart, we delivered adenovirus expressing O -GlcNAcase (Adv-GCA) into the myocardium of STZ-induced diabetic mice. Our results indicated that excessive cellular O -GlcNAcylation exists in the diabetic heart, and that in vivo GCA overexpression reduces overall cellular O -GlcNAcylation. Myocytes isolated from diabetic hearts receiving Adv-GCA exhibited improved calcium transients with a significantly shortened T decay ( P 2+ load ( P P P O -GlcNAcylation in the diabetic heart contributes to cardiac dysfunction, and reducing this excess cellular O -GlcNAcylation has beneficial effects on calcium handling and diabetic cardiac function.