Osteogenic actions of the anti-diabetic drug metformin on osteoblasts in culture

An association has been previously established between uncompensated diabetes mellitus and the loss of bone mineral density and/or quality. In this study, we evaluated the effects of metformin on the growth and differentiation of osteoblasts in culture. Treatment of two osteoblast-like cells (UMR106 and MC3T3E1) with metformin (25–500μM) for 24h led to a dose-dependent increase of cell proliferation. Metformin also promoted osteoblastic differentiation: it increased type-I collagen production in both cell lines and stimulated alkaline phosphatase activity in MC3T3E1 osteoblasts. In addition, metformin markedly increased the formation of nodules of mineralization in 3-week MC3T3E1 cultures. Metformin induced activation and redistribution of phosphorylated extracellular signal-regulated kinase (P-ERK) in a transient manner, and dosedependently stimulated the expression of endothelial and inducible nitric oxide synthases (e/iNOS). These results show for the first time a direct osteogenic effect of metformin on osteoblasts in culture, which could be mediated by activation/redistribution of ERK-1/2 and induction of e/ iNOS.Facultad de Ciencias Exacta

Osteogenic actions of the anti-diabetic drug metformin on osteoblasts in culture

An association has been previously established between uncompensated diabetes mellitus and the loss of bone mineral density and/or quality. In this study, we evaluated the effects of metformin on the growth and differentiation of osteoblasts in culture. Treatment of two osteoblast-like cells (UMR106 and MC3T3E1) with metformin (25–500μM) for 24h led to a dose-dependent increase of cell proliferation. Metformin also promoted osteoblastic differentiation: it increased type-I collagen production in both cell lines and stimulated alkaline phosphatase activity in MC3T3E1 osteoblasts. In addition, metformin markedly increased the formation of nodules of mineralization in 3-week MC3T3E1 cultures. Metformin induced activation and redistribution of phosphorylated extracellular signal-regulated kinase (P-ERK) in a transient manner, and dosedependently stimulated the expression of endothelial and inducible nitric oxide synthases (e/iNOS). These results show for the first time a direct osteogenic effect of metformin on osteoblasts in culture, which could be mediated by activation/redistribution of ERK-1/2 and induction of e/ iNOS.Facultad de Ciencias Exacta

In vivo effects of Metformin on the alterations of bone micro-architecture associated with fructose-induced Metabolic Syndrome in rats

El Síndrome Metabólico (SM) se ha asociado recientemente con una disminución en la densidad mineral ósea, y con un aumento en la incidencia de fracturas osteoporóticas. Recientemente encontramos que la Metformina por vía oral en ratas, promueve la diferenciación osteogénica de células progenitoras de médula ósea e incrementa la reparación de lesiones óseas. En este trabajo evaluamos los efectos del SM inducido por Fructosa sobre la microarquitectura ósea en ratas, y la modulación de estos efectos por Metformina administrada en forma oral. Utilizamos ratas Sprague Dawley macho jóvenes: C (control sin tratamiento), C+M (100mg/kg/día Metformina en el agua de bebida), F (10 % Fructosa en el agua de bebida) y F+M (Fructosa+Metformina en el agua de bebida). Los tratamientos se continuaron por 3 semanas luego de lo cual se tomaron muestras de sangre, previas al sacrificio de los animales. Se disecaron los fémures para evaluación histomorfométrica de la microarquitectura metafisaria por tinción con Hematoxilina-Eosina (H-E). Se observó un incremento en la glucemia y trigliceridemia en el grupo F versus el C, compatible con el desarrollo de SM. El análisis de las metáfisis femorales mostró un aumento en la densidad osteocítica trabecular para el grupo C+M (118 % del control, p<0,05). El tratamiento con Fructosa sola disminuyó la densidad osteocítica (79 % del control, p<0,05), mientras que el co-tratamiento Fructosa+Metformina (grupo F+M) revirtió parcialmente este descenso (88 % del control). Similarmente, el porcentaje de hueso trabecular en la metáfisis femoral aumentó luego del tratamiento sólo con Metformina (129 % respecto del control), se redujo en las ratas tratadas con Fructosa (89 % respecto del control), y fue intermedia en el grupo F+M (94 % respecto del control). Estos resultados muestran que el SM inducido por Fructosa en ratas altera la microarquitectura metafisaria femoral; y que estos efectos deletéreos pueden ser parcialmente prevenidos por un tratamiento oral con Metformina.Fil: Felice, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani". Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Cardiovasculares "Dr. Horacio Eugenio Cingolani"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; ArgentinaFil: Cortizo, Ana María. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; ArgentinaFil: Sedlinsky, Claudia. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; ArgentinaFil: Schurman, León. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; ArgentinaFil: McCarthy, Antonio Desmond. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; Argentin

Guías Argentinas para el diagnóstico, la prevención y el tratamiento de la osteoporosis 2015

La osteoporosis es una enfermedad en constante crecimiento y que afecta a más de 200 millones de personas en todo el mundo. Nuestras recomendaciones son guías para el diagnóstico, la prevención y tratamiento, pero no normas para las decisiones clínicas en casos individuales. El médico debe adaptarlas a situaciones en la práctica clínica cotidiana, incorporando factores personales que trascienden los límites de estas guías y hacen al saber y al arte de la práctica médica. Como todo conocimiento científico, deben ser actualizadas periódicamente a medida que se adquieran nuevas, mejores y más efectivas herramientas diagnósticas y terapéuticas.Osteoporosis is an evolving disease which affects over 200 million people worldwide. Our recommendations are guidelines for its diagnosis, prevention and treatment, but they do not constitute standards for clinical decisions in individual cases. The physician must adapt them to individual special situations, incorporating personal factors that transcend the limits of these guidelines and are dependent on the knowledge and art of the practice of Medicine. These guidelines should be reviewed and updated periodically as new, better and more effective diagnostic and therapeutic tools become available

Effects of fructose-induced metabolic syndrome on rat skeletal cells and tissue, and their responses to metformin treatment

Aims: Deleterious effects of metabolic syndrome (MS) on bone are still controversial. In this study we evaluated the effects of a fructose-induced MS, and/or an oral treatment with metformin on the osteogenic potential of bone marrow mesenchymal stromal cells (MSC), as well as on bone formation and architecture. Methods: 32 male 8 week-old Wistar rats were assigned to four groups: control (C), control plus oral metformin (CM), rats receiving 10% fructose in drinking water (FRD), and FRD plus metformin (FRDM). Samples were collected to measure blood parameters, and to perform pQCT analysis and static and dynamic histomorphometry. MSC were isolated to determine their osteogenic potential. Results: Metformin improved blood parameters in FRDM rats. pQCTand static and dynamic histomorphometry showed no significant differences in trabecular and cortical bone parameters among groups. FRD reduced TRAP expression and osteocyte density in trabecular bone and metformin only normalized osteocyte density. FRD decreased the osteogenic potential of MSC and metformin administration could revert some of these parameters. Conclusions: FRD-induced MS shows reduction in MSC osteogenic potential, in osteocyte density and in TRAP activity. Oral metformin treatment was able to prevent trabecular osteocyte loss and the reduction in extracellular mineralization induced by FRD-induced MS.Laboratorio de Investigación en Osteopatías y Metabolismo Minera

Osteogenic actions of the anti-diabetic drug metformin on osteoblasts in culture

An association has been previously established between uncompensated diabetes mellitus and the loss of bone mineral density and/or quality. In this study, we evaluated the effects of metformin on the growth and differentiation of osteoblasts in culture. Treatment of two osteoblast-like cells (UMR106 and MC3T3E1) with metformin (25–500μM) for 24h led to a dose-dependent increase of cell proliferation. Metformin also promoted osteoblastic differentiation: it increased type-I collagen production in both cell lines and stimulated alkaline phosphatase activity in MC3T3E1 osteoblasts. In addition, metformin markedly increased the formation of nodules of mineralization in 3-week MC3T3E1 cultures. Metformin induced activation and redistribution of phosphorylated extracellular signal-regulated kinase (P-ERK) in a transient manner, and dosedependently stimulated the expression of endothelial and inducible nitric oxide synthases (e/iNOS). These results show for the first time a direct osteogenic effect of metformin on osteoblasts in culture, which could be mediated by activation/redistribution of ERK-1/2 and induction of e/ iNOS

Effect of metformin on bone marrow progenitor cell differentiation: In vivo and in vitro studies

Diabetes mellitus is associated with bone loss. Patients with type 2 diabetes are frequently treated with oral antidiabetic drugs such as sulfonylureas, biguanides, and thiazolidinediones. Rosiglitazone treatment has been shown to increase adipogenesis in bone marrow and to induce bone loss. In this study we evaluated the effect of in vivo and in vitro treatment with metformin on bone marrow progenitor cells (BMPCs), as well as the involvement of AMPK pathway in its effects. The in vitro effect of coincubation with metformin and rosiglitazone on the adipogenic differentiation of BMPCs also was studied. In addition, we evaluated the effect of in vivo metformin treatment on bone regeneration in a model of parietal lesions in nondiabetic and streptozotocin-induced diabetic rats. We found that metformin administration both in vivo and in vitro caused an increase in alkaline phosphatase activity, type I collagen synthesis, osteocalcin expression, and extracellular calcium deposition of BMPCs. Moreover, metformin significantly activated AMPK in undifferentiated BMPCs. In vivo, metformin administration enhanced the expression of osteoblast-specific transcription factor Runx2/Cbfa1 and activation of AMPK in a time-dependent manner. Metformin treatment also stimulated bone lesion regeneration in control and diabetic rats. In vitro, metformin partially inhibited the adipogenic actions of rosiglitazone on BMPCs. In conclusion, our results indicate that metformin causes an osteogenic effect both in vivo and in vitro, possibly mediated by Runx2/Cbfa1 and AMPK activation, suggesting a possible action of metformin in a shift toward the osteoblastic differentiation of BMPCs.Facultad de Ciencias Exacta

Effect of metformin on bone marrow progenitor cell differentiation: In vivo and in vitro studies

Diabetes mellitus is associated with bone loss. Patients with type 2 diabetes are frequently treated with oral antidiabetic drugs such as sulfonylureas, biguanides, and thiazolidinediones. Rosiglitazone treatment has been shown to increase adipogenesis in bone marrow and to induce bone loss. In this study we evaluated the effect of in vivo and in vitro treatment with metformin on bone marrow progenitor cells (BMPCs), as well as the involvement of AMPK pathway in its effects. The in vitro effect of coincubation with metformin and rosiglitazone on the adipogenic differentiation of BMPCs also was studied. In addition, we evaluated the effect of in vivo metformin treatment on bone regeneration in a model of parietal lesions in nondiabetic and streptozotocin-induced diabetic rats. We found that metformin administration both in vivo and in vitro caused an increase in alkaline phosphatase activity, type I collagen synthesis, osteocalcin expression, and extracellular calcium deposition of BMPCs. Moreover, metformin significantly activated AMPK in undifferentiated BMPCs. In vivo, metformin administration enhanced the expression of osteoblast-specific transcription factor Runx2/Cbfa1 and activation of AMPK in a time-dependent manner. Metformin treatment also stimulated bone lesion regeneration in control and diabetic rats. In vitro, metformin partially inhibited the adipogenic actions of rosiglitazone on BMPCs. In conclusion, our results indicate that metformin causes an osteogenic effect both in vivo and in vitro, possibly mediated by Runx2/Cbfa1 and AMPK activation, suggesting a possible action of metformin in a shift toward the osteoblastic differentiation of BMPCs.Facultad de Ciencias Exacta

In vivo effects of Metformin on the alterations of bone micro-architecture associated with fructose-induced Metabolic Syndrome in rats

El Síndrome Metabólico (SM) se ha asociado recientemente con una disminución en la densidad mineral ósea, y con un aumento en la incidencia de fracturas osteoporóticas. Recientemente encontramos que la Metformina por vía oral en ratas, promueve la diferenciación osteogénica de células progenitoras de médula ósea e incrementa la reparación de lesiones óseas. En este trabajo evaluamos los efectos del SM inducido por Fructosa sobre la microarquitectura ósea en ratas, y la modulación de estos efectos por Metformina administrada en forma oral. Utilizamos ratas Sprague Dawley macho jóvenes: C (control sin tratamiento), C+M (100mg/kg/día Metformina en el agua de bebida), F (10 % Fructosa en el agua de bebida) y F+M (Fructosa+Metformina en el agua de bebida). Los tratamientos se continuaron por 3 semanas luego de lo cual se tomaron muestras de sangre, previas al sacrificio de los animales. Se disecaron los fémures para evaluación histomorfométrica de la microarquitectura metafisaria por tinción con Hematoxilina-Eosina (H-E). Se observó un incremento en la glucemia y trigliceridemia en el grupo F versus el C, compatible con el desarrollo de SM. El análisis de las metáfisis femorales mostró un aumento en la densidad osteocítica trabecular para el grupo C+M (118 % del control, p<0,05). El tratamiento con Fructosa sola disminuyó la densidad osteocítica (79 % del control, p<0,05), mientras que el co-tratamiento Fructosa+Metformina (grupo F+M) revirtió parcialmente este descenso (88 % del control). Similarmente, el porcentaje de hueso trabecular en la metáfisis femoral aumentó luego del tratamiento sólo con Metformina (129 % respecto del control), se redujo en las ratas tratadas con Fructosa (89 % respecto del control), y fue intermedia en el grupo F+M (94 % respecto del control). Estos resultados muestran que el SM inducido por Fructosa en ratas altera la microarquitectura metafisaria femoral; y que estos efectos deletéreos pueden ser parcialmente prevenidos por un tratamiento oral con Metformina.Several clinical studies have demonstrated that the Metabolic Syndrome (MS) is associated with a decrease in bone mineral density, and with an increased risk for non-vertebral osteoporotic fractures. We have recently found that orally administered Metformin induces osteogenic effects in rats, promoting osteoblastic differentiation of bone marrow progenitor cells and increasing the repair of bone lesions. In the present work we have evaluated the effects of Fructose-induced MS on bone micro-architecture in rats, and the possible modulation of these effects by orally administered Metformin. We utilized young male Sprague-Dawley rats, divided into four groups: C (non-treated controls); C+M (100 mg/kg/day of Metformin in drinking water); F (10 % of Fructose in drinking water); and F+M (Fructose+Metformin in drinking water). After three weeks of all treatments blood samples were taken, after which animals were sacrificed by cervical dislocation under anaesthesia. Femurs were then dissected for evaluation of metaphyseal micro-architecture after Haematoxilin-Eosin staining of 5 µm histological slices of decalcified bone. In particular, osteocytic density and relative trabecular volume were determined. An increase in serum glucose and triglycerides was observed in Fructose-treated rats, in accordance with the development of MS. In rats treated with Metformin alone (group C+M), the analysis of femoral metaphyses showed an increase in trabecular osteocytic density (118 % of control [group C], p&lt;0.05). Treatment with Fructose alone (group F) significantly decreased ostecytic density (79 % of control, p&lt;0.05), while co-treatment with Fructose and Metformin partially reverted this decrease (group F+M, 88 % of control). Similarly, the relative trabecular volume of femoral metaphysic was increased by treatment with Metformin alone (129% of control), was reduced in Fructose-treated rats (89 % of control), and tended to revert back to control values after Fructose-Metformin co-treatment (94 % of control). These results show for the first time that (a) Fructose-induced MS in rats alters their femoral metaphysis micro-architecture; and that (b) these deleterious effects can be partially prevented by orally administered Metformin.Laboratorio de Investigación en Osteopatías y Metabolismo Minera

Saxagliptin affects long-bone microarchitecture and decreases the osteogenic potential of bone marrow stromal cells

Diabetes mellitus is associated with a decrease in bone quality and an increase in fracture incidence. Additionally, treatment with anti-diabetic drugs can either adversely or positively affect bone metabolism. In this study we evaluated: the effect of a 3-week oral treatment with saxagliptin on femoral microarchitecture in young male non-type-2-diabetic Sprague Dawley rats; and the in vitro effect of saxagliptin and/or fetal bovine serum (FBS), insulin or insulin-like growth factor-1 (IGF1), on the proliferation, differentiation (Runx2 and PPAR-gamma expression, type-1 collagen production, osteocalcin expression, mineralization) and extracellular-regulated kinase (ERK) activation, in bone marrow stromal cells (MSC) obtained from control (untreated) rats and in MC3T3E1 osteoblast-like cells. In vivo, oral saxagliptin treatment induced a significant decrease in the femoral osteocytic and osteoblastic density of metaphyseal trabecular bone and in the average height of the proximal cartilage growth plate; and an increase in osteoclastic tartrate-resistant acid phosphatase (TRAP) activity of the primary spongiosa. In vitro, saxagliptin inhibited FBS-, insulin- and IGF1-induced ERK phosphorylation and cell proliferation, in both MSC and MC3T3E1 preosteoblasts. In the absence of growth factors, saxagliptin had no effect on ERK activation or cell proliferation. In both MSC and MC3T3E1 cells, saxagliptin in the presence of FBS inhibited Runx2 and osteocalcin expression, type-1 collagen production and mineralization, while increasing PPAR-gamma expression. In conclusion, orally administered saxagliptin induced alterations in long-bone microarchitecture that could be related to its in vitro down-regulation of the ERK signaling pathway for insulin and IGF1 in MSC, thus decreasing the osteogenic potential of these cells.Laboratorio de Investigación en Osteopatías y Metabolismo Minera