title: TP508 (Chrysalin) reverses endothelial dysfunction and increases perfusion and myocardial function in hearts with chronic ischemia.
abstract: Endothelial dysfunction (ED) is characterized by impaired nitric oxide (NO) signaling, decreased NO-dependent vasodilatation, increased vascular inflammation, and diminished response to angiogenic factors. TP508 (Chrysalin), an angiogenic tissue repair peptide, was tested for potential effects on myocardial revascularization and ED using a porcine model of chronic myocardial ischemia. TP508 increased perfusion in ischemic regions up to16-fold (P < .02) and doubled myocardial wall thickening (P < .02) relative to placebo controls. Ischemic arterioles exhibited impaired NO-mediated vasodilation and diminished NO production. TP508 reversed ischemic effects, increasing NO-mediated vasodilation (P < .05), endothelial nitric oxide synthase (eNOS) expression, and NO production. In human endothelial cells, TP508 stimulated eNOS activation (1.84 +/- 0.2-fold; P < .02), increased NO production (85 +/- 18%; P < .02), and prevented hypoxia-induced eNOS downregulation (P < .01). Thus, TP508 reverses ED both in porcine ischemic hearts and cultured human endothelial cells. These results suggest potential therapeutic benefit of TP508 in myocardial revascularization and treatment of ED-related diseases.
authors.affiliation: Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Texas A&M University, College Station, Texas, USA.
authors.forename: Theresa W
authors.initials: TW
authors.lastname: Fossum
authors.forename: Barbara
authors.initials: B
authors.lastname: Olszewska-Pazdrak
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Mertens
authors.forename: Lori A
authors.initials: LA
authors.lastname: Makarski
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Miller
authors.forename: Travis W
authors.initials: TW
authors.lastname: Hein
authors.forename: Lih
authors.initials: L
authors.lastname: Kuo
authors.forename: Fred
authors.initials: F
authors.lastname: Clubb
authors.forename: Gerald M
authors.initials: GM
authors.lastname: Fuller
authors.forename: Darrell H
authors.initials: DH
authors.lastname: Carney