title: Betacellulin overexpression in mesenchymal stem cells induces insulin secretion in vitro and ameliorates streptozotocin-induced hyperglycemia in rats.
abstract: Betacellulin (BTC), a ligand of the epidermal growth factor receptor, has been shown to promote growth and differentiation of pancreatic β-cells and to improve glucose metabolism in experimental diabetic rodent models. Mesenchymal stem cells (MSCs) have been already proved to be multipotent. Recent work has attributed to rat and human MSCs the potential to differentiate into insulin-secreting cells. Our goal was to transfect rat MSCs with a plasmid containing BTC cDNA to guide MSC differentiation into insulin-producing cells. Prior to induction of cell MSC transfection, MSCs were characterized by flow cytometry and the ability to in vitro differentiate into mesoderm cell types was evaluated. After rat MSC characterization, these cells were electroporated with a plasmid containing BTC cDNA. Transfected cells were cultivated in Dulbecco's modified Eagle medium high glucose (H-DMEM) with 10 mM nicotinamide. Then, the capability of MSC-BTC to produce insulin in vitro and in vivo was evaluated. It was possible to demonstrate by radioimmunoassay analysis that 10(4) MSC-BTC cells produced up to 0.4 ng/mL of insulin, whereas MSCs transfected with the empty vector (negative control) produced no detectable insulin levels. Moreover, MSC-BTC were positive for insulin in immunohistochemistry assay. In parallel, the expression of pancreatic marker genes was demonstrated by molecular analysis of MSC-BTC. Further, when MSC-BTC were transplanted to streptozotocin diabetic rats, BTC-transfected cells ameliorated hyperglycemia from over 500 to about 200 mg/dL at 35 days post-cell transplantation. In this way, our results clearly demonstrate that BTC overabundance enhances glucose-induced insulin secretion in MSCs in vitro as well as in vivo.
authors.affiliation: Laboratorio de Embriologia e Diferenciagao Celular, Centro de Pesquisas UFRGS-HCPA, Porto Alegre, Brazil.
authors.forename: Ana H
authors.initials: AH
authors.lastname: Paz
authors.forename: Gabrielle Dias
authors.initials: GD
authors.lastname: Salton
authors.forename: Ana
authors.initials: A
authors.lastname: Ayala-Lugo
authors.forename: Cristiano
authors.initials: C
authors.lastname: Gomes
authors.forename: Paula
authors.initials: P
authors.lastname: Terraciano
authors.forename: Rosana
authors.initials: R
authors.lastname: Scalco
authors.forename: Claudia Cilene Fernandes Correia
authors.initials: CC
authors.lastname: Laurino
authors.forename: Eduardo Pandolfi
authors.initials: EP
authors.lastname: Passos
authors.forename: Marlon R
authors.initials: MR
authors.lastname: Schneider
authors.forename: Luise
authors.initials: L
authors.lastname: Meurer
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Cirne-Lima
mesh_terms: D000818:Animals; D066259:Betacellulin; D001786:Blood Glucose / Q000378:metabolism; D002454:Cell Differentiation; D002478:Cells, Cultured; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000378:metabolism* / Q000628:therapy; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006943:Hyperglycemia / Q000139:chemically induced / Q000378:metabolism* / Q000628:therapy; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D013311:Streptozocin
chemical_list: C587851:BTC protein, human; D066259:Betacellulin; D001786:Blood Glucose; C587853:Btc protein, rat; D007328:Insulin; D036341:Intercellular Signaling Peptides and Proteins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D013311:Streptozocin