title: Taurine supplementation of a low protein diet fed to rat dams normalizes the vascularization of the fetal endocrine pancreas.
abstract: In rats, an isoenergetic low protein diet (LP) given throughout gestation perturbs the development of the endocrine pancreas by reducing beta-cell mass and islet vascularization at birth. Taurine, an important amino acid during development, has been found to be low in fetal and maternal plasma. When added to a LP diet, taurine normalizes beta-cell mass. Therefore, we investigated the ability of taurine to correct altered islet vascularization. Rats were given 20% [control (C)] or 8% (LP) protein in the diet with or without supplementation with 25 g/L taurine (T) in drinking water (C+T and LP+T) during gestation and lactation. Immunostaining for vascular endothelial growth factor (VEGF) and fetal liver kinase-1 (Flk-1), a VEGF receptor, was performed on fetal and neonatal pancreatic sections. Blood vessel density and blood vessel number were analyzed morphometrically on semi-thin sections. Taurine supplementation restored a normal volume and numerical density of vessels in fetal islets. The number of cells showing immunoreactivity for VEGF and Flk-1 was reduced by 33 and 45%, respectively, in islet cells from LP fetuses. In 1-mo-old pups, VEGF-positive cells remained decreased by nearly 22%. Both VEGF and Flk-1 were restored in pancreatic endocrine cells of fetuses and pups given taurine. The LP diet induced a threefold overexpression of Flk-1 in ductal cells, which contain precursors of beta cells. However, taurine supplementation was without effect. In conclusion, underexpression of VEGF and Flk-1 is associated with the lower fetal islet vascularization induced by the maternal malnutrition. The addition of taurine to the maternal diet prevents such damage and has a potential role in islet vasculogenesis.
authors.affiliation: Laboratoire de Biologie Cellulaire, World Health Collaborating Center for the Development of the Endocrine Pancreas, Université Catholique de Louvain, B-1348 Louvain-La-Neuve, Belgium.
authors.forename: Samira
authors.initials: S
authors.lastname: Boujendar
authors.forename: Edith
authors.initials: E
authors.lastname: Arany
authors.forename: David
authors.initials: D
authors.lastname: Hill
authors.forename: Claude
authors.initials: C
authors.lastname: Remacle
authors.forename: Brigitte
authors.initials: B
authors.lastname: Reusens
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000033:anatomy & histology; D018753:Diet, Protein-Restricted; D019587:Dietary Supplements; D016228:Endothelial Growth Factors / Q000378:metabolism; D005260:Female; D005333:Fetus / Q000033:anatomy & histology* / Q000098:blood supply / Q000166:cytology / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D007515:Islets of Langerhans / Q000196:embryology*; D008222:Lymphokines / Q000378:metabolism; D010183:Pancreatic Ducts / Q000196:embryology; D011247:Pregnancy; D011270:Pregnancy, Animal; D051381:Rats; D017208:Rats, Wistar; D013654:Taurine / Q000008:administration & dosage*; D042461:Vascular Endothelial Growth Factor A; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000378:metabolism; D042442:Vascular Endothelial Growth Factors
chemical_list: D016228:Endothelial Growth Factors; D036341:Intercellular Signaling Peptides and Proteins; D008222:Lymphokines; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D013654:Taurine; D040301:Vascular Endothelial Growth Factor Receptor-2