Monosaccharides and the VO(IV) metal ion: Equilibrium, thermal studies and hypoglycemic effect
Guiotoku, M; Mena Barreto Silva, FR; Azzolini, JC; Ramalho Merce, AnaL; Mangrich, AS; Sala, LF; Szpoganicz, B
| HERO ID | 4947390 |
|---|---|
| In Press | No |
| Year | 2007 |
| Title | Monosaccharides and the VO(IV) metal ion: Equilibrium, thermal studies and hypoglycemic effect |
| Authors | Guiotoku, M; Mena Barreto Silva, FR; Azzolini, JC; Ramalho Merce, AnaL; Mangrich, AS; Sala, LF; Szpoganicz, B |
| Journal | Polyhedron |
| Volume | 26 |
| Issue | 6 |
| Page Numbers | 1269-1276 |
| Abstract | Protonation and complexation equilibriums of monosaccharides and the VO(IV)metal ion in aqueous solution were studied as well as their effect on the hyperglycernia of diabetic rats. The complexes formed were characterized by potentiometric titrations, paramagnetic resonance spectroscopy (EPR) and thermogravimetric-differential scanning calorimetry (TGA-DSC). The system involving D-gluconic acid (HGlu) and oxovanadium(IV) (VO2+) was chosen to study the serum glucose levels in alloxan-induced diabetic rats. A binuclear species was detected in small quantities, which was formed by coordination of two HGlu molecules and two VO2+ ions through a hydroxide bridge. The mononuclear species formed by HGlu and VO2+ were confirmed by EPR. The anisotropic spectra obtained from aqueous frozen solutions (77 K) are characteristic of mononuclear VO-hexoses. The cyclic sugars D-ribone-1,4-lactone (Riblac), D-galactone-1,4-lactone (Galac) and 2-deoxy-D-glucopyranose (dGlu) showed weak interactions with the metal ion and they are not able to hold the metal in solution above pH 4.6 resulting in hydrolysis of the metal ion. Also, the acute treatment with sugar complexes of HGlu-VO led to a significant hypoglycemic effect (23% and 18% by intraperitoneal or oral gavage treatment, respectively) in diabetic rats. These results show the potential effectiveness of VO-HGlu complexes as anti-hyperglycemic agents through intraperitoneal injection in alloxaninduced diabetic rats. (C) 2006 Elsevier Ltd. All rights reserved. |
| Doi | 10.1016/j.poly.2006.10.032 |
| Wosid | WOS:000246283900016 |
| Is Certified Translation | No |
| Dupe Override | No |
| Is Public | Yes |
| Keyword | vanadyl complexes; potentiometric titration; EPR; TGA-DSC; D-gluconic acid; hypoglycemic; diabetes |