Enhancement of Beta-cell mass and function by INGAP-PP: role of islet angiogenesis

ROMÁN CAROLINA LISI; MAIZTEGUI, BÁRBARA; FLORES, LUIS EMILIO; DEL ZOTTO, HÉCTOR; GAGLIARDINO, JUAN JOSE

Vancouver

Congreso; World Diabetes Congress 2015; 2015

IDF

Islet angiogenesis is needed for embryonic β-cell differentiation and INGAP-PP administration increases Beta-cell mass and function in rats.Aim:To determine the role of islet angiogenesis in the mechanism by which INGAP-PP enhances β-cell mass and function. Methods: In vivo study: adult Wistar rats were treated (ip) for 10 days with saline (Control) or INGAP-PP (500µg/day). Thereafter, plasma glucose, insulin and triglyceride levels were measured and HOMA-IR and ? β were calculated. Cell apoptotic rate and gene expression (qPCR and western blot) of VEGF-A, VEGFR-2, integrin β1, laminin β1, insulin, Pdx-1, Ngn3, Bcl-2, Bad and caspases 8, 9 and 3 were determined in islets isolated from both groups of rats. In vitro study: islets isolated from normal rats were cultured for 4 days in medium with different composition: control (no additions); INGAP-PP (10µg/ml INGAP-PP); Rapamycin (control or INGAP-PP medium + 10ng/ml rapamycin); and VEGF (10ng/ml VEGF-A). We determined VEGF released to the medium (ELISA) and glucose-stimulated insulin secretion (RIA) Statistis: ANOVA and t test; significant differences were considered when p