Synthesis of a new vanadyl(IV) complex with trehalose (TreVO): insulin-mimetic activities in osteoblast-like cells in culture

Vanadium compounds show interesting biological and pharmacological properties. Some of them display insulin-mimetic effects and others produce antitumor actions. The bioactivity of vanadium is present in inorganic species like the vanadyl(IV) cation or vanadate( V) anion. Nevertheless, the development of new vanadium derivatives with organic ligands which improve the beneficial actions and decrease the toxic effects is of great interest. On the other hand, the mechanisms involved in vanadium bioactivity are still poorly understood. A new vanadium complex of the vanadyl(IV) cation with the disaccharide trehalose (TreVO), Na6 [VO(Tre)2].4H2O, here reported, shows interesting insulin- mimetic properties in two osteoblast cell lines, a normal one (MC3T3E1) and a tumoral one (UMR106). The complex affected the proliferation of both cell lines in a different manner. On tumoral cells, TreVO caused a weak stimulation of growth at 5 lM but it inhibited cell proliferation in a dose-response manner between 50 and 100 lM. TreVO significantly inhibited UMR106 differentiation (15–25% of basal) in the range 5–100 lM. On normal osteoblasts, TreVO behaved as a mitogen at 5–25 lM. Different inhibitors of the MAPK pathway blocked this effect. At higher concentrations (75–100 lM), the complex was a weak inhibitor of the MC3T3E1 proliferation. Besides, TreVO enhanced glucose consumption by a mechanism independent of the PI3-kinase activation. In both cell lines, TreVO stimulated the ERK phosphorylation in a dose- and time-dependent manner. Different inhibitors (PD98059, wortmannin, vitamins C and E) partially decreased this effect, which was totally inhibited by their combination. These results suggest that TreVO could be a potential candidate for therapeutic treatments

Synthesis of a new vanadyl(IV) complex with trehalose (TreVO): insulin-mimetic activities in osteoblast-like cells in culture

Vanadium compounds show interesting biological and pharmacological properties. Some of them display insulin-mimetic effects and others produce antitumor actions. The bioactivity of vanadium is present in inorganic species like the vanadyl(IV) cation or vanadate( V) anion. Nevertheless, the development of new vanadium derivatives with organic ligands which improve the beneficial actions and decrease the toxic effects is of great interest. On the other hand, the mechanisms involved in vanadium bioactivity are still poorly understood. A new vanadium complex of the vanadyl(IV) cation with the disaccharide trehalose (TreVO), Na6 [VO(Tre)2].4H2O, here reported, shows interesting insulin- mimetic properties in two osteoblast cell lines, a normal one (MC3T3E1) and a tumoral one (UMR106). The complex affected the proliferation of both cell lines in a different manner. On tumoral cells, TreVO caused a weak stimulation of growth at 5 lM but it inhibited cell proliferation in a dose-response manner between 50 and 100 lM. TreVO significantly inhibited UMR106 differentiation (15–25% of basal) in the range 5–100 lM. On normal osteoblasts, TreVO behaved as a mitogen at 5–25 lM. Different inhibitors of the MAPK pathway blocked this effect. At higher concentrations (75–100 lM), the complex was a weak inhibitor of the MC3T3E1 proliferation. Besides, TreVO enhanced glucose consumption by a mechanism independent of the PI3-kinase activation. In both cell lines, TreVO stimulated the ERK phosphorylation in a dose- and time-dependent manner. Different inhibitors (PD98059, wortmannin, vitamins C and E) partially decreased this effect, which was totally inhibited by their combination. These results suggest that TreVO could be a potential candidate for therapeutic treatments.Facultad de Ciencias Exacta

Synthesis of a new vanadyl(IV) complex with trehalose (TreVO): insulin-mimetic activities in osteoblast-like cells in culture

Vanadium compounds show interesting biological and pharmacological properties. Some of them display insulin-mimetic effects and others produce antitumor actions. The bioactivity of vanadium is present in inorganic species like the vanadyl(IV) cation or vanadate( V) anion. Nevertheless, the development of new vanadium derivatives with organic ligands which improve the beneficial actions and decrease the toxic effects is of great interest. On the other hand, the mechanisms involved in vanadium bioactivity are still poorly understood. A new vanadium complex of the vanadyl(IV) cation with the disaccharide trehalose (TreVO), Na6 [VO(Tre)2].4H2O, here reported, shows interesting insulin- mimetic properties in two osteoblast cell lines, a normal one (MC3T3E1) and a tumoral one (UMR106). The complex affected the proliferation of both cell lines in a different manner. On tumoral cells, TreVO caused a weak stimulation of growth at 5 lM but it inhibited cell proliferation in a dose-response manner between 50 and 100 lM. TreVO significantly inhibited UMR106 differentiation (15–25% of basal) in the range 5–100 lM. On normal osteoblasts, TreVO behaved as a mitogen at 5–25 lM. Different inhibitors of the MAPK pathway blocked this effect. At higher concentrations (75–100 lM), the complex was a weak inhibitor of the MC3T3E1 proliferation. Besides, TreVO enhanced glucose consumption by a mechanism independent of the PI3-kinase activation. In both cell lines, TreVO stimulated the ERK phosphorylation in a dose- and time-dependent manner. Different inhibitors (PD98059, wortmannin, vitamins C and E) partially decreased this effect, which was totally inhibited by their combination. These results suggest that TreVO could be a potential candidate for therapeutic treatments.Facultad de Ciencias Exacta

Three new vanadyl(IV) complexes with non-steroidal anti-inflammatory drugs (Ibuprofen, Naproxen and Tolmetin) : Bioactivity on osteoblast-like cells in culture

The synthesis and spectral and magnetic characterization of VO(2+) complexes with Ibuprofen (2-(4-isobutylphenyl)propionic acid), Naproxen (6-methoxy-alpha-methyl-2-naphthalene acetic acid) and Tolmetin (1-methyl-5-(4-methylbenzoyl)-1H-pyrrole-2-acetic acid) were studied. The complexes [VO(Ibu)(2)] x 5CH(3)OH, [VO(Nap)(2)] x 5CH(3)OH and [VO(Tol)(2)] were obtained from methanolic solutions under nitrogen atmosphere. The biological activities of these complexes on the proliferation of two osteoblast-like cells in culture (MC3T3E1 and UMR106) were compared with that of the vanadyl(IV) cation. The complexes exhibited different effects depending on the concentration and the cellular type, while no effect was observed for their parent drugs.Facultad de Ciencias Exacta

Non-enzymatic glycosylation of a type I collagen matrix: effects on osteoblastic development and oxidative stress

BACKGROUND: The tissue accumulation of protein-bound advanced glycation endproducts (AGE) may be involved in the etiology of diabetic chronic complications, including osteopenia. The aim of this study was to investigate the effect of an AGE-modified type I collagen substratum on the adhesion, spreading, proliferation and differentiation of rat osteosarcoma UMR106 and mouse non-transformed MC3T3E1 osteoblastic cells. We also studied the role of reactive oxygen species (ROS) and nitric oxide synthase (NOS) expression on these AGE-collagen mediated effects. RESULTS: AGE-collagen decreased the adhesion of UMR106 cells, but had no effect on the attachment of MC3T3E1 cells. In the UMR106 cell line, AGE-collagen also inhibited cellular proliferation, spreading and alkaline phosphatase (ALP) activity. In preosteoblastic MC3T3E1 cells (24-hour culture), proliferation and spreading were significantly increased by AGE-collagen. After one week of culture (differentiated MC3T3E1 osteoblasts) AGE-collagen inhibited ALP activity, but had no effect on cell number. In mineralizing MC3T3E1 cells (3-week culture) AGE-collagen induced a decrease in the number of surviving cells and of extracellular nodules of mineralization, without modifying their ALP activity. Intracellular ROS production, measured after a 48-hour culture, was decreased by AGE-collagen in MC3T3E1 cells, but was increased by AGE-collagen in UMR106 cells. After a 24-hour culture, AGE-collagen increased the expression of endothelial and inducible NOS, in both osteoblastic cell lines. CONCLUSIONS: These results suggest that the accumulation of AGE on bone extracellular matrix could regulate the proliferation and differentiation of osteoblastic cells. These effects appear to depend on the stage of osteoblastic development, and possibly involve the modulation of NOS expression and intracellular ROS pathways

Non-enzymatic glycosylation of a type 1 collagen matrix: effects on osteoblastic development and oxidative stress

Background : The tissue accumulation of protein-bound advanced glycation endproducts (AGE) may be involved in the etiology of diabetic chronic complications, including osteopenia. The aim of this study was to investigate the effect of an AGE-modified type I collagen substratum on the adhesion, spreading, proliferation and differentiation of rat osteosarcoma UMR106 and mouse nontransformed MC3T3E1 osteoblastic cells. We also studied the role of reactive oxygen species (ROS) and nitric oxide synthase (NOS) expression on these AGE-collagen mediated effects. Results: AGE-collagen decreased the adhesion of UMR106 cells, but had no effect on the attachment of MC3T3E1 cells. In the UMR106 cell line, AGE-collagen also inhibited cellular proliferation, spreading and alkaline phosphatase (ALP) activity. In preosteoblastic MC3T3E1 cells (24-hour culture), proliferation and spreading were significantly increased by AGE-collagen. After one week of culture (differentiated MC3T3E1 osteoblasts) AGE-collagen inhibited ALP activity, but had no effect on cell number. In mineralizing MC3T3E1 cells (3-week culture) AGE-collagen induced a decrease in the number of surviving cells and of extracellular nodules of mineralization, without modifying their ALP activity. Intracellular ROS production, measured after a 48-hour culture, was decreased by AGE-collagen in MC3T3E1 cells, but was increased by AGE-collagen in UMR106 cells. After a 24-hour culture, AGE-collagen increased the expression of endothelial and inducible NOS, in both osteoblastic cell lines. Conclusions: These results suggest that the accumulation of AGE on bone extracellular matrix could regulate the proliferation and differentiation of osteoblastic cells. These effects appear to depend on the stage of osteoblastic development, and possibly involve the modulation of NOS expression and intracellular ROS pathways.Facultad de Ciencias Exacta

Spectroscopic Characterization of a VO²⁺ Complex of Oxodiacetic Acid and its Bioactivity on Osteoblast-like Cells in Culture

The oxovanadium(IV) complex of oxodiacetic acid (H₂oda) of stoichiometry [VO(oda)(H₂O)₂], which presents an unprecedented tridentate OOO coordination, was thoroughly characterized by infrared, Raman, electronic, and electron paramagnetic resonance spectroscopies. The biological activity of the complex on the cell proliferation and differentiation was tested on osteoblast-like cells (MC3T3E1 osteoblastic mouse calvaria-derived cells and UMR106 rat osteosarcoma-derived cells) in culture. The complex caused inhibition of cellular proliferation in both osteoblast-like cells in culture, but the cytotoxicity was stronger in the normal (MC3T3E1) than in the tumoral (UMR106) osteoblasts. The effect of the complex in cell differentiation was tested through the specific activity of alkaline phosphatase of the UMR106 cells because they expressed a high activity of this enzyme. What occurs with other vanadium compounds [VO(oda)(H₂O)₂] is an inhibitory agent of osteoblast differentiation.Facultad de Ciencias ExactasCentro de Química Inorgánic

Antitumoral properties of two new vanadyl(IV) complexes in osteoblasts in culture: role of apoptosis and oxidative stress

Background: Vanadium derivatives have been reported to display different biological effects, and in particular antineoplastic activity has been demonstrated in both in vivo and in vitro studies. Purpose:To study the effect of two new organic vanadyl(IV) complexes (one with glucose, GluVO, and the other with naproxen, NapVO) in osteosarcoma cells. Methods:UMR106 osteosarcoma cells and, for comparison, nontransformed MC3T3E1 osteoblasts were used. Proliferation and differentiation were assessed using the crystal violet assay and ALP specific activity, respectively. Morphological alterations were assessed by light microscopy. Lipid peroxidation was evaluated in terms of production of thiobarbituric acid-reactive substances (TBARS) and apoptosis was measured using annexin V. Extracellular regulated kinase (Erk) activation was investigated by Western blotting. Results:Vanadium complexes caused morphological alterations and they strongly inhibited UMR106 cell proliferation and differentiation. In contrast, in MC3T3E1 cells, these vanadium derivatives had a relatively weak action. In UMR106 tumoral cells there was a significant increase in TBARS production. Both vanadium complexes induced apoptosis and activation of Erk. PD98059, an inhibitor of Erk phosphorylation, did not block the vanadium-induced antitumoral action. However, the antioxidants vitamins C and E abrogated the apoptosis and TBARS production induced by the vanadium complexes. Conclusions:GluVO and NapVO exerted an antitumoral effect in UM106 osteosarcoma cells. They inhibited cell proliferation and differentiation. While the Erk cascade seems not to be directly related to the bioactivity of these vanadium derivatives, the action of both vanadium complexes with organic ligands may be mediated by apoptosis and oxidative stress

Antitumoral properties of two new vanadyl(IV) complexes in osteoblasts in culture: role of apoptosis and oxidative stress

Background: Vanadium derivatives have been reported to display different biological effects, and in particular antineoplastic activity has been demonstrated in both in vivo and in vitro studies. Purpose: To study the effect of two new organic vanadyl(IV) complexes (one with glucose, GluVO, and the other with naproxen, NapVO) in osteosarcoma cells. Methods: UMR106 osteosarcoma cells and, for comparison, nontransformed MC3T3E1 osteoblasts were used. Proliferation and differentiation were assessed using the crystal violet assay and ALP specific activity, respectively. Morphological alterations were assessed by light microscopy. Lipid peroxidation was evaluated in terms of production of thiobarbituric acid-reactive substances (TBARS) and apoptosis was measured using annexin V. Extracellular regulated kinase (Erk) activation was investigated by Western blotting. Results: Vanadium complexes caused morphological alterations and they strongly inhibited UMR106 cell proliferation and differentiation. In contrast, in MC3T3E1 cells, these vanadium derivatives had a relatively weak action. In UMR106 tumoral cells there was a significant increase in TBARS production. Both vanadium complexes induced apoptosis and activation of Erk. PD98059, an inhibitor of Erk phosphorylation, did not block the vanadium-induced antitumoral action. However, the antioxidants vitamins C and E abrogated the apoptosis and TBARS production induced by the vanadium complexes. Conclusions: GluVO and NapVO exerted an antitumoral effect in UM106 osteosarcoma cells. They inhibited cell proliferation and differentiation. While the Erk cascade seems not to be directly related to the bioactivity of these vanadium derivatives, the action of both vanadium complexes with organic ligands may be mediated by apoptosis and oxidative stress.Facultad de Ciencias Exacta