title: Study of the antidiabetic capacity of the VO(dmpp)2 complex.
abstract: In this work we report biochemical ex vivo studies with a vanadium compound containing a pyridinone ligand, the bis(1,2-dimethyl-3-hydroxy-4-pyridinonate)oxovanadium (IV), V(IV)O(dmpp)(2), which has shown to have promising antidiabetic activity. The experiments were carried out on primary adipocytes of 6-8 week old Wistar rats. Insulin-stimulated glucose uptake studies were performed using a radioactive assay by measuring the (U)-(14)C-glucose taken up by the isolated adipocytes for 30 min. Adipocytes were incubated with and without insulin and in the presence and absence of different concentrations of V(IV)O(dmpp)(2) (100-500 microM) for 45 min. We observed that in a nontoxic concentration, as demonstrated by the Alamar Blue test, V(IV)O(dmpp)(2) significantly increases glucose uptake, in the absence of insulin, by 5-folds higher than basal, and it has a significant inhibitory effect of 78% on free fatty acid release in isolated adipocytes from normal rats. We also demonstrated that it promotes the phosphorylation of Akt1, a key protein in the insulin signaling cascade. These results were compared with those obtained with another vanadium compound reported in the literature, with a similar structure, the bis(maltolato)oxovanadium (IV) (BMOV), which is now in clinical trials. Our ex vivo results clearly indicate that V(IV)O(dmpp)(2) is a good candidate to be a promising drug for the treatment of diabetes and other metabolic disorders.
authors.affiliation: Center for Neuroscience and Cell Biology (CNC) of Coimbra, University of Coimbra, Portugal.
authors.forename: Marta
authors.initials: M
authors.lastname: Passadouro
authors.forename: Ana M
authors.initials: AM
authors.lastname: Metelo
authors.forename: Alice S
authors.initials: AS
authors.lastname: Melão
authors.forename: Joana R
authors.initials: JR
authors.lastname: Pedro
authors.forename: Henrique
authors.initials: H
authors.lastname: Faneca
authors.forename: Eugénia
authors.initials: E
authors.lastname: Carvalho
authors.forename: M Margarida C A
authors.initials: MM
authors.lastname: Castro
mesh_terms: D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D015153:Blotting, Western; D002478:Cells, Cultured; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D007004:Hypoglycemic Agents / Q000737:chemistry / Q000494:pharmacology*; D008297:Male; D015394:Molecular Structure; D051381:Rats; D017208:Rats, Wistar; D017968:Vanadium Compounds / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D005230:Fatty Acids, Nonesterified; D007004:Hypoglycemic Agents; D017968:Vanadium Compounds; D005947:Glucose