title: T3 enhances Ang2 in rat aorta in myocardial I/R: comparison with left ventricle.
abstract: Angiogenesis is important for recovery after tissue damage in myocardial ischemia/reperfusion, and tri-iodothyronine (T3) has documented effects on angiogenesis. The angiopoietins 1/2 and tyrosine kinase receptor represent an essential system in angiogenesis controlling endothelial cell survival and vascular maturation. Recently, in a 3-day ischemia/reperfusion rat model, the infusion of a low dose of T3 improved the post-ischemic recovery of cardiac function.Adopting this model, our study aimed to investigate the effects of T3 on the capillary index and the expression of angiogenic genes as the angiopoietins 1/2 and tyrosine kinase receptor system, in the thoracic aorta and in the left ventricle. In the thoracic aorta, T3 infusion significantly improved the angiogenic sprouting and angiopoietin 2 expression. Instead, Sham-T3 group did not show any significant increment of capillary density and angiopoietin 2 expression. In the area at risk (AAR) of the left ventricle, T3 infusion did not increase capillary density but restored levels of angiopoietin 1, which were reduced in I/R group. Angiopoietin 2 levels were similar to Sham group and unchanged by T3 administration. In the remote zone, T3 induced a significant increment of both angiopoietin 1/2. In conclusion, T3 infusion induced a different response of angiopoietin 1/2 between the ventricle (the AAR and the remote zone) and the thoracic aorta, probably reflecting the different action of angiopoietin 1/2 in cardiomyocytes and endothelial cells. Overall, these data suggest a new aspect of T3-mediated cardioprotection through angiogenesis.
authors.affiliation: Institute of Clinical PhysiologyCNR, Pisa, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Sabatino
authors.affiliation: Institute of Clinical PhysiologyCNR, Pisa, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Kusmic
authors.affiliation: Institute of Clinical PhysiologyCNR, Pisa, Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Nicolini
authors.affiliation: Department of BiologyUnit of General Physiology, University of Pisa, Pisa, Italy.
authors.forename: Rosario
authors.initials: R
authors.lastname: Amato
authors.affiliation: Department of BiologyUnit of General Physiology, University of Pisa, Pisa, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Casini
authors.affiliation: Institute of Clinical PhysiologyCNR, Pisa, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Iervasi
authors.affiliation: Institute of Clinical PhysiologyCNR, Pisa, Italy balzan@ifc.cnr.it.
authors.forename: Silvana
authors.initials: S
authors.lastname: Balzan
mesh_terms: D042702:Angiopoietin-2 / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000378:metabolism*; D004195:Disease Models, Animal; D004452:Echocardiography; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006352:Heart Ventricles / Q000187:drug effects / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D039302:Integrin alphaVbeta3 / Q000378:metabolism; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000378:metabolism; D051381:Rats; D013974:Thyroxine / Q000097:blood / Q000378:metabolism; D013997:Time Factors; D014284:Triiodothyronine / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism*; D016276:Ventricular Function / Q000187:drug effects
chemical_list: D042702:Angiopoietin-2; D039302:Integrin alphaVbeta3; D014284:Triiodothyronine; D013974:Thyroxine
keywords: angiogenesis; angiopoietin 1/2; myocardial ischemia/reperfusion; thyroid hormones; tyrosine kinase receptor 2