Effect of alendronate on healing of bone defect and gingival tissue in osteopenic rats / Efecto del alendronato en la reparación de defectos óseos y tejido gingival en ratas con osteopenia

The aim was to evaluate bone repair and gingival tissue repair in osteopenic rats. Fifteen female wistar rats were included; in all of them ovariectomy was realized to induce osteopenia; after 45 days, the animals were submitted to 2 surgical techinques 1) dental extraction of the upper central incisor with no socket preservation and 2) 5 mm cranial defect in the calvarium; 5 rats were included in the control group (G1) withput alendronate application; in the group 2 (G2) was used subcutenous alendronate (0.5 mg/kg) once for three weeks and then was realizd the both surgical techniques. In group 3 (G3), after ovariectomy was realized the both dental extraction and the calvarium defect and after that was realized the alendronate protocol. In each group, after six week was realized euthanasia and descriptive histological analysis of the surgical areas involved. In bone formation of the 5 mm cranial defect was observed with good progression in the 3 experimental models and no modification in quality of bone repair was observed. For the gingival tissue in the extraction socket, no differences were observed between G1 and G3. On other hand, in G2 a thinner and reduced gingival epithelium was found. Our results showed that alendronate was not an obstacle for bone repair; deficiencies in re-epithelialization of oral mucosa show the impact of alendronate before dental extraction.

El objetivo fue evaluar la reparación ósea y gingival en ratas con osteopenia. Quince ratas wistar hembras fueron incluidas; en todas ellas se realizo ovarectomia y fue realizada la inducción de osteopenia; después de 45 días, los animales fueron sometidos a dos técnicas quirúrgicas 1) extracciones dentales del incisivo central superior sin preservación alveolar y 2) creación de un defecto craneano de 5 mm en la calota; 5 animales fueron incluidos como grupo control (G1) sin la aplicación de alendronato; en el grupo 2 (G2) se utilizó alendronato subcutáneo (0,5 mg/kg) una vez a la semana durante 3 semanas. En el grupo 3 (G3), después de la ovarectomia se realizó la exodoncia y el defecto en el cráneo y después de ello se inicio el protocolo con alendronato. En cada grupo, después de seis semanas se realizó la eutanasia con descripción histológica de los hallazgos. En el hueso formado en el defecto craneano de 5 mm se observó una adecuada progresión de reparación en los 3 modelos experimentales y no se observó cambios importantes en el modelo de reparación. Para el tejido gingival en el sitio de extracción, no se observaron diferencias entre el grupo G1 y G3. Por otra parte, el G2 presentó un tejido mas delgado con reducción del epitelio gingival; nuestros resultados demuestran que el alendronato no fue un obstáculo en la reparación ósea; deficiencias en la re epitelización de la mucosa oral muestran el impacto del alendronato después de la exodoncia.

Evaluación de la Administración Infiltrativa de vitamina E y alendronato en la Reparación de Alvéolos Post Exodoncia de Ratas / Evaluation of the Infiltrative Administration of Vitamin E and Alendronate in the Repair of Alveoli Post-Extraction in Rats

RESUMEN: Los bisfosfonatos (BP) disminuyen la resorción ósea al frenar la actividad de los osteoclastos. La vitamina E es antioxidante y su efecto positivo en el hueso sería mediante la prevención del estrés oxidativo. Se estudió la administración infiltrativa de Alendronato y Vitamina E para determinar si favorecían la formación de hueso en la reparación ósea del alvéolo postexodoncia. Se utilizaron ratas machos Wistar (n=96), de 90 ± 15 g, se les realizó la exodoncia de los primeros molares inferiores. Fueron dividos en 4 grupos: Un grupo control (C) recibió solución salina. El grupo AL 0,5 mg/ Kg; grupo E recibió 20 mg/kg; y grupo con tratamiento combinado AL y E. Los animales se sacrificaron a los 0, 7, 15 y 30 días postextracción. Se realizó la resección de las mandíbulas; las muestras fueron descalcificadas con EDTA y luego se incluyeron en parafina. Se realizaron cortes histológicos y se colorearon con Hematoxilina/Eosina. Se realizó análisis histológico e histomorfométrico. Se utilizó análisis de Varianza (ANOVA). En el análisis histológico, a los 7 y 15 días el grupo E presentó mayor neoformación de tejido óseo que los otros grupos. A los 30 días se observó hueso maduro con presencia de osteonas en el grupo E. En el estudio histomorfométrico a los 15 y 30 días se evidencian diferencias significativas en el número de osteoblastos por mm lineal, entre el grupo AL + E y C (p<0,01) y a los 30 días se encontró diferencia entre el grupo E y C (p<0,01). Al medir espesor trabecular se observó a los 30 días diferencias significativas entre el grupo AL+E y C (p<0,01) y entre el grupo C y E (p<0,01). La Vitamina E demostró que administrada por vía infiltrativa favorece la remodelación ósea en los alvéolos post exodoncia.

ABSTRACT: Bisphosphonates (BP) decrease bone resorption to curb the activity of the osteoclasts. Vitamin E is an antioxidant and its positive effect on the bone would be by preventing oxidative stress. Infiltrative Alendronate and vitamin E administration wasstudied to determine if they favored the formation of bone in bone repair of the postextraction alveolus. Male Wistar rats were used (n = 96), 90 ± 15 g, underwent extraction of the lower first molars. They were divided into 4 groups: A control group (C) received saline. The Group at the 0.5 mg/Kg; Group E received 20 mg/kg; and combined treatment group to AL and E. The animals were sacrificed at days 0, 7, 15 and 30 post extraction. With the resection of the jaws; samples were decalcified with EDTA and then included in paraffin. Histological cuts were made and colored with Hematoxylin/ eosin. Histomorphometric and histological analysis was performed. We used analysis of variance (ANOVA). In the histological analysis, 7 to 15 days the Group E presented greater neoformation of bone tissue than other groups. At 30 days mature bone was observed, with presence of osteons in the Group E. Study shows significant differences in the number of osteoblast histomorphometric function to 15 to 30 days by linear mm, among the group to the + E and C (p < 0.01) and 30-day difference was found among the Group E and C (p < 0.01). When measuring thick trabecular, significant differences were observed at 30 days between the AL+E and C Group (p < 0.01) and between C and E (p < 0.01). Vitamin E showed that administered infiltrative favors the bone remodeling in post extraction sockets.

Efecto de Vitamina E y Alendronato sobre la Densidad Mineral en Hueso Maxilar de Ratas / Effect of Vitamin E and Alendronate on Mineral Density in Rat Maxillary Bone

RESUMEN: El balance óseo está mediado por una regulación inmunoendócrina, siendo éste un complejo proceso. Entre las acciones llevadas a cabo para mantener la densidad y estructura del esqueleto son variadas las farmacoterapias utilizadas. Diversos estudios han demostrado que tanto Alendronato (AL) y Vitamina E (E) contribuyen a la inhibición de la reabsorción ósea. El objectivo de este trabajo fue estudiar el efecto de la administración combinada de (AL) por vía subcutánea y (E) se administró tres veces por semana también por vía subcutánea con una dosificación de 20 mg/kg de peso corporal. La fórmula farmacéutica fue de 0,5 mg/kg de peso corporal para AL, y 20 mg/kg de vitamina E. El efecto se evaluó en ratas machos Wistar (n=108), de 90 ± 20 g, divididas en 4 grupos. Se realizó la exodoncia de los primeros molares inferiores. La droga se inyectó en forma subcutánea en tiempos 0, 7, 15 y 30 días post cirugía. Las imágenes de las mandíbulas fueron adquiridas mediante radiovisiógrafo, en cada tiempo experimental y fueron analizadas con el Software Image ProPlus versión 4,1 de Media Cibernetics. Estudios estadísticos: no paramétrico: prueba de Kruskal-Wallis Resultados: El grupo C (que registró la media de intensidad más baja), se diferenció significativamente de los grupos E y A-E (p<0,001), no así del grupo que utilizó únicamente Al (p=0,070; p>0,05). Los grupos Al, E y el combinado Al-E no se diferenciaron significativamente entre sí (p>0,05 en todos los casos). Los datos evaluados sirven para mostrar una tendencia favorable en relación al efecto beneficioso de la combinación de AL y vitamina E.

ABSTRACT: The bone balance is mediated by an immunoendocrine regulation, this being a complex process. A number of pharmacotherapies are used among the actions taken to maintain the density and structure of the skeleton. Several studies have shown that both Alendronate (AL) and Vitamin E (E) contribute to the inhibition of bone resorption. Objective: To study the effect of combined administration of (LA) subcutaneously and (E) was administered three times per week also subcutaneously with a dosage of 20 mg / kg body weight. The pharmaceutical formulation was 0.5 mg / kg body weight for AL and 20 mg / kg vitamin E. The effect was evaluated in male Wistar rats (n = 108), 90 ± 20 g, divided into 4 groups. Extraction of the first lower molars was performed. The drug was injected subcutaneously at time 0, 7, 15 and 30 days post-surgery. The images of the jaws were acquired by radiovisiography, at each experimental time and were analyzed with Image ProPlus Software version 4.1 of Media Cibernetics. Statistical studies: non-parametric: Kruskal-Wallis test Group C (which recorded the lowest mean intensity) was significantly different from the E and AE groups (p <0.001), but not from the group that used only Al (P = 0.070, p> 0.05). The Al, E and combined Al-E groups did not differ significantly from each other (p> 0.05 in all cases). The data evaluated serve to show a favorable trend in relation to the beneficial effect of the combination of AL and vitamin E.

Fracturas vertebrales múltiples postsuspensión de denosumab: revisión del tema a partir de dos casos clínicos / Discontinuation of denosumab and multiple vertebral fractures: report of two cases and review of the literature

Los tratamientos para osteoporosis se indican por tiempo variable dependiendo del tipo de droga, anabólica o anticatabólica, y de la gravedad de la enfermedad. Denosumab es un anticuerpo monoclonal totalmente humano que inhibe a RANK-L evitando de esa manera la interacción entre RANKL-RANK, con la consiguiente inhibición de la formación de los osteoclastos, su activación y sobrevida. Disminuye la resorción ósea cortical y trabecular. Su administración subcutánea de 60 mg cada 6 meses al cabo de 3 años ha demostrado reducción de la resorción ósea, incremento de la densidad mineral ósea y disminución de las fracturas vertebrales, no vertebrales y de cadera. Está indicado para el tratamiento de la osteoporosis con alto riesgo de fractura. Su mecanismo de acción es reversible. Se han descripto pérdida de la DMO y elevación de los marcadores de remodelado óseo postsuspensión. Una situación clínica grave son las fracturas vertebrales múltiples postsuspensión. Este evento es infrecuente y se lo atribuye a un rebote del remodelado óseo, postulándose se postula una predisposición especial, probablemente relacionada con microRNA. Se escriben dos mujeres con osteoporosis que presentaron este cuadro. Las fracturas ocurrieron entre 7 y 10 meses posteriores a la última dosis de denosumab. Registraron elevación de C-telopéptidos y disminución de la DMO conjuntamente con las fracturas vertebrales agudas en cascada. (AU)

The duration of osteoporosis treatments depends on the drug type, anabolic or anticatabolic, and the severity of the disease. Denosumab is a fully human monoclonal antibody that inactivates RANK-L, inhibiting the RANKL-RANK interaction . This inhibits osteoclast formation, activation, and survival. It also reduces cortical and trabecular bone resorption. Subcutaneous administration of 60 mg every 6 months for 3 years has reduced bone resorption, increased bone mineral density (BMD) and decreased vertebral, non-vertebral and hip fractures. It is indicated for the treatment of osteoporosis with high risk of fracture. Denosumab mechanism of action is reversible. After discontinuation, loss of BMD and elevation of bone turnover markers have been observed. In addition, multiple vertebral fractures after the suspension of the drug have been reported. These rebound-associated vertebral fractures are rare. A special genetic predisposition related to miRNA has been proposed. Two women with this clinical presentation are described. Fractures occurred between 7 and 10 months respectively after the last dose of denosumab. They presented with an increase in circulating C-telopeptid levels and a decrease inBMD with acute multiple vertebral fractures. (AU)

Effect of local application of alendronate and parathyroid hormone on craniofacial bone repair - a preliminary study

Abstract This study aimed to evaluate the effect of two methods of local application of alendronate and parathyroid hormone (PTH) on bone repair and the systemic implications. A critically sized defect (5 mm) was created in the cranial region of twenty-five male Wistar rats, and the bone removed was particulated, and grafted back to the defect with different treatments. The animals were randomly divided into five groups: A1- bone graft immersion in alendronate solution (3 mg/kg) for 5 minutes; P1- bone graft immersion in PTH solution (20 µg); A2- weekly local applications of alendronate 1 mg/kg; P2- weekly local applications of PTH (20 µg); C- no drugs were used. The animals were euthanized 60 days after surgery. Cranial bone blocks were removed for histological, histomorphometric, and immunohistochemical analyses. MMP-2 and MMP-9 were used for immunolabeling. The kidneys, liver, and brain were also removed from all the rats for histological analysis. The data were submitted for statistical analysis with a level of significance of 0.05 (One-way ANOVA). The group C and group P2 presented a higher quantity of viable bone particles than the remaining groups. Groups A1, A2, and P1 presented with fewer viable bone particles than the control group, with a predominance of non-mineralized connective tissue. The histomorphometric analysis revealed no differences in relative bone area or MMP-2 or MMP-9 immunolabeling between the groups (p>0.05). Group A2 showed presence of fat in the liver consistent with hepatic steatosis. Changes in brain tissue were observed in groups A1 and P1.

Resumo Este estudo visou avaliar o efeito de dois métodos de aplicação local de alendronato e de paratormônio (PTH) no reparo ósseo e avaliar as implicações sistêmicas. Um defeito de tamanho crítico (5 mm) foi criado na calota craniana de vinte e cinco ratos Wistar machos, e o osso removido foi particulado e enxertado de volta no defeito com diferentes tratamentos. Os animais foram divididos aleatoriamente em cinco grupos: A1: imersão do enxerto ósseo em solução de alendronato (3 mg/kg) durante 5 min; P1- imersão do osso em solução de PTH (20 μg); A2- aplicações locais semanais de alendronato 1 mg/kg; P2- aplicações locais semanais de PTH 20 μg; C: não foram utilizados medicamentos. Os animais foram eutanasiados 60 dias após a cirurgia. Foram removidos os blocos ósseos envolvendo a região do defeito para realização das análises histológica, histomorfométrica e imuno-histoquímica. MMP2 e MMP9 foram as imunomarcações utilizadas. Os rins, fígado e cérebro também foram removidos de todos os ratos para análise histológica. Os dados foram submetidos à análise estatística com um nível de significância de 0,05 (One-way ANOVA). A análise histológica revelou que o grupo C e o grupo P2 apresentaram maior quantidade de partículas ósseas viáveis do que as apresentadas pelos demais grupos. Os grupos A1, A2 e P1 apresentaram menos partículas ósseas viáveis em comparação com o grupo controle com predominância de tecido conjuntivo não mineralizado. A análise histomorfométrica não revelou diferenças entres os grupos na área óssea relativa ou em MMP2 e MMP9 (p>0,05). O grupo A2 mostrou presença de gordura no fígado consistente com esteatose hepática. Alterações no tecido cerebral foram observadas nos grupos A1 e P1.

Análisis Histomorfométrico de la Asociación de Aceite de Oliva y Bisfosfonatos en la Remodelación Ósea Periimplantaria / Histomorphometric Analysis of the Association of Olive Oil and Bisphosphonates on Peri-Implant Bone Remodeling

RESUMEN: Los bisfosfonatos son potentes inhibidores de la resorción ósea. El aceite de oliva (O) presenta propiedades anti-inflamatorias y anti-oxidantes. Estudiar el efecto del tratamiento combinado de alendronato (AL) y pamidronato (PA) por vía subcutánea y de O vía oral sobre la regeneración tisular de cavidades óseas neoformadas.: 54 ratas macho de la línea Wistar, se dividieron en 6 grupos. Grupo control (C), recibieron solución salina vía subcutánea. Grupo (AL) recibió 0,5 mg de AL/Kg de peso corporal de por vía subcutánea. Grupo (PA) recibió de igual manera que el grupo anterior. Grupo (O) fue tratado con aceite de oliva con la dieta, 50 g/ Kg de comida. Grupo (ALO) recibió tratamiento combinado con AL y O. Grupo (PAO) recibió de igual tratamiento. Los sacrificios para la toma de muestras fueron a los 15, 30, 60 y 90 días. Para los estudios histopatológicos los cortes fueron teñidos con HE y observados con microscopía óptica. Los estudios estadísticos se realizaron a través del análisis de la variancia. A los quince días las áreas de los osteocitos del grupo PA se diferencian significativamente sólo respecto al grupo AL. En cuanto a la Densidad trabecular se observa un incremento de tejido óseo en todos los grupos. O mejora cualitativamente la estructura del hueso trabecular y cortical, preservando la mineralización, el tamaño y la estructura de los cristales minerales Esto sugiere que O representa una opción terapéutica prometedora para la prevención y tratamiento de las patologías óseas.

ABSTRACT: Bisphosphonates are potent inhibitors of bone resorption. Olive oil (O) has anti-inflammatory and anti-oxidant properties. To study the effect of combined treatment with alendronate (AL) and pamidronate (PA) subcutaneously or orally, and on tissue regeneration of newly formed bone cavities, we divided 54 male Wistar rats into 6 groups. Control group (C) received saline subcutaneously. Group (AL) received 0.5 mg of AL / kg body weight subcutaneously. Group (PA) received the same as the previous group. (O) was treated with olive oil diet, 50 g / kg of food. Group (ALO) received combined treatment with AL and O. Group (PAO) received the same treatment. The animals were euthanized for sampling at 15, 30, 60 and 90 days. For histopathology sections were stained with HE and observed these with light microscopy. Statistical studies were performed by analysis of variance. Fifteen days osteocytes areas of the PA group were significantly different only for the AL group. As the density increased trabecular bone tissue was observed in all groups. O qualitatively improved the structure of trabecular and cortical bone mineralization while preserving the size and structure of the mineral crystals. This suggests that O represents a promising therapeutic option for prevention and treatment of bone diseases.

Role of 1% alendronate gel as adjunct to mechanical therapy in the treatment of chronic periodontitis among smokers

Abstract Objective Alendronate (ALN) inhibits osteoclastic bone resorption and triggers osteostimulative properties both in vivo and in vitro, as shown by increase in matrix formation. This study aimed to explore the efficacy of 1% ALN gel as local drug delivery (LDD) in adjunct to scaling and root planing (SRP) for the treatment of chronic periodontitis among smokers. Material and Methods 75 intrabony defects were treated in 46 male smokers either with 1% ALN gel or placebo gel. ALN gel was prepared by adding ALN into carbopol-distilled water mixture. Clinical parameters [modified sulcus bleeding index, plaque index, probing depth (PD), and periodontal attachment level (PAL)] were recorded at baseline, at 2 months, and at 6 months, while radiographic parameters were recorded at baseline and at 6 months. Defect fill at baseline and at 6 months was calculated on standardized radiographs by using the image analysis software. Results Mean PD reduction and mean PAL gain were found to be greater in the ALN group than in the placebo group, both at 2 and 6 months. Furthermore, a significantly greater mean percentage of bone fill was found in the ALN group (41.05±11.40%) compared to the placebo group (2.5±0.93%). Conclusions The results of this study showed 1% ALN stimulated a significant increase in PD reduction, PAL gain, and an improved bone fill compared to placebo gel in chronic periodontitis among smokers. Thus, 1% ALN, along with SRP, is effective in the treatment of chronic periodontitis in smokers.

Effect of 1% sodium alendronate in the non-surgical treatment of periodontal intraosseous defects: a 6-month clinical trial

Abstract Background and objectives Few studies have evaluated the effect of the topical application of sodium alendronate (ALN) on the treatment of intrabuccal bone defects, especially those caused by periodontitis. This 6-month randomized placebo controlled clinical trial aimed at evaluating the effect of non-surgical periodontal treatment associated with the use of 1% ALN, through clinical evaluations and cone-beam computed tomography (CBCT). Material and Methods Twenty individuals with chronic periodontitis underwent periodontal examination at the baseline as well as 3 and 6 months after periodontal treatment, registering clinical attachment level (CAL), periodontal probing depth (PPD), and bleeding on probing (BOP) as the clinical outcomes. After manual scaling and root planing, 40 bilateral sites with interproximal vertical bone defects were randomly treated with either 1% ALN gel or a placebo. Bone defects were evaluated through CBCT at the baseline and 6 months post-treatment. The clinical and CBCT parameters were compared using the Wilcoxon and Friedman tests (p<0.05). Results Although ALN produced a greater CAL gain when compared to the placebo at 6 months post-treatment (p=0.021), both treatments produced similar effects on the PPD, BOP, and bone height. Significant differences in bone fill were observed only in patients of the ALN group (4.5 to 3.8 mm; p=0.003) at 6 months post-treatment. Conclusions Topical application of 1% ALN might be a beneficial adjuvant to non-surgical periodontal therapy.

Evaluación biomecánica del efecto de bisfosfonatos y aceite de oliva en un modelo de remodelación óseo en fémur de rata: efectos en la remodelación ósea / Biomechanical evaluation of the effect of bisphosphonates and olive oil in a model of bone remodeling in rat femur: effects on bone remodeling

Estudios han demostrado que el aceite de oliva (O) con sus compuestos fenólicos tienen efectos positivos en diversos biomarcadores fisiológicos. Análisis previos han demostrado que los bisfosfonatos, son potentes inhibidores de la resorción ósea. Estudiar el efecto del tratamiento combinado de alendronato (AL) y pamidronato (PA) y de O sobre la regeneración ósea. Las fórmulas se dosificaron 0,5 mg/kg de peso para AL, y de 0,6 mg/kg de peso para PA. El O se administró en la dieta, 50 g/Kg. Cincuenta y cuatro ratas macho de la línea Wistar se dividieron en 6 grupos. El grupo control (C), recibió semanalmente 0,3 ml/100 g de solución salina vía subcutánea. El grupo (AL) recibió semanalmente por vía subcutánea en el miembro posterior izquierdo. El grupo (PA) se colocó igual que el grupo anterior. El grupo (O) fue tratado en la alimentación y en las áreas de la cirugía recibieron inyección subcutánea con solución fisiológica. El grupo (ALO) recibió tratamiento combinado con AL y O. El grupo (PAO) se trató igual al anterior. Se obtuvieron muestras de fémur en tiempos 15, 30, 60 y 90 días, que se incluyeron en solución fisiológica y mantenidos a -20 C. Los estudios estadísticos se realizaron a través del análisis de la variancia a dos y tres criterios de clasificación. Sólo el factor días influye significativamente sobre los valores. Las diferencias entre drogas no resultaron estadísticamente significativas. Tampoco se verificó interacción significativa entre los factores Droga y etapa. Los valores más elevados de fuerza de ruptura aplicada, se registraron a los 90 días. No se encontraron diferencias significativas en los ensayos biomecánicos, poniendo de manifiesto la acción sistémica de los fármacos. Estas acciones fueron benéficas al aumentar la rigidez.

Studies have shown that olive oil (O) with its phenolic compounds have positive effects on various physiological biomarkers. Previous analyzes have shown that bisphosphonates are potent inhibitors of bone resorption. The objective of this work was to study the effect of combined treatment with alendronate (AL) and pamidronate (PA) and O on bone regeneration. Formulas 0.5 mg/kg for AL dosed, and 0.6 mg/kg for PA. O was administered in the diet, 50 g/kg. Fifty-four male Wistar rats were divided into 6 groups. The control group (C) received weekly 0.3 mL/100 g of saline subcutaneously. Group (AL) received weekly subcutaneously in the left posterior limb. Group (PA) was placed as the previous group. Group (O) was treated in food and in the areas of surgery received subcutaneous injection with saline. The (ALO) group received combined treatment with Al and O. The group (PAO) was treated the same as before. Femur samples at times 15, 30, 60 and 90 days, were included in physiological solution and maintained at -20 °C were obtained. Statistical studies were conducted through analysis of variance to two and three classification criteria. The ANOVA showed that only days factor significantly influences the values of the variables (p <0.05). The differences between drugs were not statistically significant (p> 0.05). Nor was there significant drug interaction between factors and stage (p> 0.05) was verified. The highest values of force rupture applied occurred at 90 days. No significant differences were found in the biomechanical testing, demonstrating the systemic action of drugs. These actions were beneficial to increase rigidity.

Experimental osteonecrosis: development of a model in rodents administered alendronate

Abstract The main objective of this study was to cause bisphosphonate-related osteonecrosis of the jaws to develop in a rodent model. Adult male Holtzman rats were assigned to one of two experimental groups to receive alendronate (AL; 1 mg/kg/week; n = 6) or saline solution (CTL; n = 6). After 60 days of drug therapy, all animals were subjected to first lower molar extraction, and 28 days later, animals were euthanized. All rats treated with alendronate developed osteonecrosis, presenting as ulcers and necrotic bone, associated with a significant infection process, especially at the inter-alveolar septum area and crestal regions. The degree of vascularization, the levels of C-telopeptide cross-linked collagen type I and bone-specific alkaline phosphatase, as well as the bone volume were significantly reduced in these animals. Furthermore, on radiographic analysis, animals treated with alendronate presented evident sclerosis of the lamina dura of the lower first molar alveolar socket associated with decreased radiographic density in this area. These findings indicate that the protocol developed in the present study opens new perspectives and could be a good starting model for future property design.

Sequential administration of alendronate and strontium ranelate: histomorphometry and bone biomechanics in ovariectomized animals

Bisphosphonates are the first choice therapy for the pharmaco logical treatment of osteoporosis. Following reports of cases of bisphosphonaterelated osteonecrosis of the jaw and atypical femur fracture, the safety of longterm use of bisphosphonates has been evaluated, resulting in the proposal of strontium as an alternative drug. No experimental study using a sequential administration design has been reported to date. Hence, the aim of this study was to evaluate the effect on bone tissue of ovariectomized rats of administration of alendronate followed by strontium ranelate. Fortyeight female Wistar rats were ovariectomized on day 1 of the experiment. Beginning on day 30, they were administered 0.3 mg/kg/week of alendronate (ALN) or vehicle (VEH) for 8 weeks. Two groups (ALN and corresponding control) were euthanized at this time, and the remaining animals were divided into 4 groups and given 290 mg/kg/day of strontium ranelate (SR) in their drinking water (TW) or only water for 4 months. Experimental groups were: ALN+SR, ALN+TW, VEH+SR, VEH+TW, ALN and VEH. The tibiae and hemimandibles were resected for histomorphometric evaluation, and the right femur was used to perform biomechanical studies. ANOVA and Bonferroni test were applied. Diaphyseal stiffness, maximum elastic load and fracture load increased in animals that received alendronate, regardless of whether or not they received subsequent SR treatment. Fracture load also increased in VEH+ SR versus control (VEH+TW). Subchondral and interradicular bone volumes were significantly higher in animals that received ALN than in those that received vehicle. No difference was observed in cortical area or thickness of the tibia among treatments. The results obtained with the model presented here, evaluating tibial and mandibular interradicular bone, showed that the combination of ALN and SR and administration of ALN alone are equally effective in preventing bone loss associated with ovariectomyinduced estrogen depletion.

Si bien la primera opción terapéutica para el tratamiento farmacológico de la osteoporosis son los bisfosfonatos (BPs), luego de los primeros reportes en 2003 de los casos de osteone crosis de mandíbula asociada al uso de dichas drogas y las fracturas atípicas de fémur, se ha evaluado su seguridad a largo plazo. Además, en aquellos pacientes que no responden al tratamiento con BPs y mantienen elevado el riesgo de fractura, es necesario suspender su administración y alternar con otras drogas. Una de las que se ha utilizado en la clínica luego del tratamiento con BPs es el ranelato de estroncio (SR). Existen varios trabajos clínicos que reportan los efectos de la administra ción secuencial de ambas drogas, aunque estudios experi men tales con un diseño secuencial aun no se han reportado. Por ello el objetivo de este trabajo ha sido evaluar el efecto de la administración secuencial de alendronato, seguido de ranelato de estroncio sobre el tejido óseo de ratas ovariectomizadas. Se utilizaron 48 ratas Wistar hembras de dos meses de edad divididas en 6 grupos de 8 animales cada uno. El día 1 de experiencia todas fueron ovariectomizadas. El día 30 se comenzó con la administración de alendronato (ALN) en una dosis de 0.3 mg/kg/semana o vehículo (VEH) durante 8 semanas. Luego de este período se sacrificaron dos grupos (uno que recibió ALN y su correspondiente control (sólo vehículo). Los cuatro grupos restantes continuaron con ranelato de estroncio (SR) en el agua de bebida durante 4 meses en una dosis de 290 mg/kg/día o sólo agua corriente( TW) Luego de ese período fueron eutanasiados. Así, los grupos experimentales conformados fueron: ALN+SR, ALN+TW, VEH+SR, VEH+TW, ALN y VEH. Para los estudios histomorfométricos se extrajeron ambas tibias y hemimandíbulas; para el estudio biomecánico se utilizó el fémur derecho. Los resultados fueron analizados mediante el test de ANOVA y el test de Bonferroni. Incrementaron significativamente la rigidez diafisaria, la carga elástica límite y la carga de fractura aquellos grupos que recibieron alendronato versus aquellos que no lo recibieron, independientemente del tratamiento posterior con SR. La carga de fractura además fue mayor en el grupo VEH+SR versus el control (VEH+TW). En cuanto al volumen óseo subcondral e interradicular evaluado histomorfométricamente fue significativamente mayor en aquellos animales que recibieron ALN versus aquellos que recibieron vehículo. No se detectaron diferencias entre aquellos grupos que recibieron SR y sus controles. El área y espesor cortical de la tibia no mostraron diferencias entre grupos. Los resultados obtenidos en el modelo estudiado tanto a nivel del volumen óseo subcondral y cortical de la tibia como a nivel del hueso interradicular del maxilar inferior, mostraron que la combinación de ALN con SR y la administración aislada de ALN son igualmente efectivas para prevenir la pérdida ósea causada por la depleción estrogénica de la ovariectomía.

Formulation of gastroresistant tablets containing sodium alendronate-loaded blend microparticles / Formulação de comprimidos gastro-resistentes que contêm na mistura micropartículas carregadas de alendronato de sódio

Sodium alendronate is an antiresorptive drug used for the treatment of postmenopausal osteoporosis. However, its oral administration is associated with low bioavailability and gastroesophageal irritation. This work aimed at developing tablets containing sodium alendronate-loaded microparticles by direct compression to achieve a safe and effective form. The parameters evaluated were average weight, hardness, thickness and drug content. In vitro release tests were carried out using simulated gastric and intestinal fluids, and the profiles were analyzed through the Korsmeyer-Peppas mono- or biexponential dependent approaches. Tablets presented adequate average weight, thickness, good mechanical properties and drug content close to 100%. Moreover, the formulation released less than 11% of sodium alendronate in gastric fluid, exhibiting a good gastroresistance. At pH 6.8, almost 100% of the drug was released in 12h, showing a prolonged profile. The mathematical modeling indicated that the experimental data was better fitted to the biexponential equation. Furthermore, a good correlation coefficient was obtained for the Korsmeyer-Peppas model and the release exponent suggested that the drug dissolution was driven by anomalous transport. In conclusion, the microparticulated tablets can be considered a promising alternative for oral delivery of sodium alendronate...

O alendronato de sódio é um fármaco da classe dos bisfosfonatos, comumente utilizado no tratamento da osteoporose pós-menopausa. Entretanto, sua administração oral está associada à baixa biodisponibilidade e irritação gastroesofágica. Este trabalho objetivou o desenvolvimento de comprimidos contendo micropartículas de alendronato de sódio por compressão direta, a fim de obter uma forma segura e eficaz. Os parâmetros avaliados foram peso médio, dureza, espessura e teor de fármaco. Estudos de liberação in vitro foram realizados utilizando fluído gástrico e intestinal simulado e o perfil de liberação foi analisado pelos modelos matemáticos de Korsmeyer-Peppas, mono- e biexponencial. Os comprimidos apresentaram peso médio adequado, espessura, dureza e teor próximo a 100%. Além disso, a formulação liberou menos de 11% do fármaco em fluído gástrico, mostrando uma boa gastrorresistência. Em pH 6,8, em torno de 100% do fármaco foram liberados em 12 h, apresentando liberação prolongada. A modelagem matemática indica que os resultados seguem a equação biexponencial. Pela análise do expoente de liberação obtido no modelo de Korsmeyer-Peppas sugere-se que a dissolução do fármaco ocorre por transporte anômalo. Concluindo, a preparação dos comprimidos microparticulados pode ser considerada uma alternativa promissora para a liberação oral do alendronato de sódio...

Endoscopic comparison of alendronate alone and the enteric-coated alendronate with calcitriol combination in postmenopausal Korean females

BACKGROUND/AIMS: This study was performed to compare the mucosal findings after esophagogastroduodenoscopy in two groups before and after the use of alendronate only and following administration of the enteric-coated alendronate (5 mg) and calcitriol (0.5 microg) combined drug (Maxmarvil, Yuyu Co.). METHODS: The study population consisted of 33 postmenopausal healthy female volunteers, aged 50 to 70 years (mean age, 58 +/- 5) without gastrointestinal symptoms and with normal baseline endoscopic findings. Esophagogastroduodenoscopy was performed at baseline and was repeated 2 weeks later after daily intake of Maxmarvil (n = 17 subjects) or alendronate only (n = 16 subjects). Mucosal injury scores were reported by an endoscopist after 2 weeks of treatment with each medication schedule. RESULTS: Esophageal mucosal injuries developed in two of 16 subjects in the alendronate only group and 0 of 17 in the Maxmarvil group. Gastric mucosal injuries developed in eight subjects in the alendronate group and four subjects in the Maxmarvil group; this difference was statistically significant. CONCLUSIONS: The mucosal damage scores for the alendronate group (total score 24) were significantly higher than those for the Maxmarvil group (total score 9) in the esophagus and stomach. Therefore, this study suggested that enteric-coated Maxmarvil is less harmful to gastrointestinal mucosa than alendronate, and may improve the tolerability of osteoporosis medication in clinical practice.

Efficacy and Safety of Monthly 150 mg Oral Ibandronate in Women with Postmenopausal Osteoporosis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND/AIMS: The aim of this study was to assess the efficacy and safety of monthly oral 150 mg ibandronate in women with postmenopausal osteoporosis (PMO). METHODS: A systematic review and meta-analysis were performed to determine treatment efficacy and safety outcomes between monthly oral 150 mg ibandronate and weekly 70 mg alendronate, daily 2.5 mg ibandronate, and a placebo. RESULTS: Eight randomized controlled trials were included in this systematic review and meta-analysis. Once-monthly 150 mg ibandronate therapy was clinically comparable to weekly 70 mg alendronate, showing increased bone mineral density (BMD) in both the lumbar spine and total hip. Pooled data from two cross-over trials showed that significantly more women with PMO preferred once-monthly ibandronate therapy to once-weekly alendronate therapy (relative risk [RR], 2.422; 95% confidence interval [CI], 2.111 to 2.825; p < 1 x 10(-8)) and found the monthly ibandronate regimen more convenient than the weekly alendronate regimen (RR, 3.096; 95% CI, 2.622 to 3.622; p < 1 x 10(-8)). Monthly 150 mg ibandronate therapy resulted in a significantly higher change in BMD of the lumbar spine than with the placebo. A once monthly 150 mg regimen produced greater increases in lumbar spine, total hip, femoral neck, and trochanter BMD than daily treatment, with a similar incidence of adverse events between the groups. CONCLUSIONS: Once monthly 150 mg ibandronate therapy was clinically comparable to weekly 70 mg alendronate, and patients strongly preferred the convenience of monthly ibandronate over weekly alendronate. Monthly 150 mg ibandronate was superior to, and as well tolerated as, the daily treatment.

O alendronato de sódio na prevenção da osteopenia secundária à imobilização gessada, em ratas: avaliação histomorfométrica / Alendronate sodium to prevent osteopenia caused by cast immobilization in female rats: histomorphometric evaluation

OBJETIVO: Analisar, por meio da histomorfometria, o efeito do alendronato de sódio sobre o trabeculado ósseo de ratos, quando administrado simultaneamente com imobilização gessada. MÉTODOS: Foram utilizados quatro grupos com cinco fêmeas de ratos Wistar: 1) imobilizado; 2) não imobilizado + alendronato; 3) imobilizado + alendronato; e 4) controle. A imobilização foi feita com gesso pelvipodálico aplicado até o membro posterior direito e o alendronato foi administrado em doses semanais. O período de observação foi de 28 dias e realizada histomorfometria da metáfise proximal da tíbia, com análise do número de trabéculas, volume ósseo, espessura trabecular e separação trabecular. RESULTADOS: O grupo imobilizado apresentou volume ósseo menor que os demais grupos. Os animais que receberam alendronato semanal, tanto imobilizados, quanto não imobilizados, apresentaram volume ósseo maior que o controle. A espessura trabecular no grupo imobilizado foi menor do que nos grupos controle e não imobilizado que recebeu alendronato, mas não apresentou diferença significativa em relação ao imobilizado com alendronato. O grupo imobilizado apresentou separação trabecular maior que os demais grupos. Os grupos não imobilizado, sem imobilização que recebeu alendronato e imobilizado que recebeu alendronato apresentaram aumento no número de trabéculas em relação ao grupo imobilizado. CONCLUSÃO: A imobilização empregada efetivamente levou à osteopenia, verificada pela diminuição de todos os principais parâmetros histomorfométricos estudados. Estas alterações foram prevenidas pela administração concomitante de alendronato sódico, exceto com relação à espessura trabecular. O alendronato de sódio foi capaz de aumentar os parâmetros morfométricos, mesmo em animais não imobilizados.

OBJECTIVE: Using histomorphometric means to analyze the effect of alendronate sodium on the bone trabeculate of rats administered concomitantly with cast immobilization. METHODS: Female Wistar rats were distributed in four groups with five animals each: 1) cast-immobilized; 2) no immobilization + alendronate; 3) cast-immobilized + alendronate; and 4) control. Immobilization was done with pelvipodalic cast applied till the right hind limb and alendronate was administered in weekly doses. The observation period was 28 days and histomorphometric evaluations were performed in the proximal tibial metaphysis, analyzing the number of trabeculae, bone volume, trabecular thickness, and trabecular separation. RESULTS: The immobilized group presented less bone volume than the other groups. The animals receiving alendronate every week, whether or not immobilized, presented a greater bone volume than the control group. Trabecular thickness in the immobilized group was less than in the control and in the non-immobilized groups that received alendronate, but had no significant difference when compared to the immobilized with alendronate group. The immobilized group presented greater trabecular separation than the other groups. In the non-immobilized groups, the non-immobilized group that received alendronate and the immobilized group that received alendronate presented an increased number of trabeculae when compared to the immobilized group. CONCLUSION: The immobilization used led to osteopenia, as confirmed by the decrease in all of the main histomorphometric parameters studied. Such changes were prevented with the concomitant administration of alendronate sodium, exception being made to the trabecular thickness. Alendronate sodium was able to increase morphometric parameters, even in non-immobilized animals.

Efecto sobre el tejido óseo de la aplicación subcutánea de una nueva formulación en base a alendronato: efecto sobre tejido óseo del alendronato / Effect on bone tissue of subcutaneous application of a new formulation based on Alendronate: effect of alendronate on bone

Estudios previos han demostrado que los aminobisfosfonatos, como el alendronato de sodio es un potente inhibidor de la resorción ósea, incrementa la densidad mineral del hueso y reducen los riesgos en fracturas de mujeres postmenopáusicas. El objetivo de este trabajo fue desarrollar una nueva formulación en base a alendronato para ser aplicada en forma subcutánea, ya que no existe en el mercado, e investigar sus efectos sobre un defecto óseo creado experimentalmente. La fórmula farmacéutica fue preparada con una dosificación de 0,5 mg/Kg de peso, se le añadió Cloruro de Na y citrato de Na, pH final de 5,5 en medios estériles. El control fueron buffers sin principios activos. Tanto la droga en estado puro como a la formulación se le realizaron curvas de citotoxicidad (Neutral Red Uptake Method), para comprobar que ambas drogas no producían efectos adversos. El efecto de alendronato se evaluó en cavidades realizadas en las tibias de ratas machos Wistar, las cuales fueron divididas en dos grupos uno control y otro problema. Los animales fueron inyectados con buffers sin droga (grupo control) y con 0,5 mg/Kg de alendronato (grupo experimental) Tanto el alendronato como el control fueron administrados en forma subcutánea, inmediatamente posterior a la cirugía, cercana a la zona de trabajo, en tiempos 0, 7, 14 y 30 días. Los parámetos de estudio fueron Rx de la zona bajo estudio a los tiempos establecidos. Todos los animales fueron sacrificados por sobredosis con éter. El análisis estadístico se realizó con Anova. La curva muestra que a bajas concentraciones la viabilidad es mayor al 98 por ciento, al aumentar la concentración de la droga las células comienzan a verse afectadas, pero la viabilidad nunca baja del 70 por ciento, por más que se siga agregando droga. Las Rx muestran diferencias estadísticamente significativas (p=0,05) entre los dos grupos, observándose formación ósea en cuanto a volumen

Previous studies have demonstrated that the bisphosphonates, as the alendronate of sodium is a powerful inhibitor of the bone resorption, it increases the mineral density of the bone and reduce the risks in fractures of postmenopausal women. The objective of this study was to develop and to investigate a new formulation on the basis of alendronate, since it does not exist in the market, to be placed in subcutaneous form in the surgical site. The pharmaceutical formula was prepared with a metering of 0.5 mg/Kg of weight, him it added Chloride of Na and citrato of Na, pH final of 5.5 in sterile means. The control was buffers without active principles. As much the drug in pure state as to the formulation cytotoxicity curves in fibroblast cell were made to him (Neutral Network Uptake Method), in order to verify that as much the pure drug as the prepared one did not produce adverse effects. The alendronate effect was evaluated in cavities made in the male tibias of rats Wistar, which were divided in two groups one control and another problem. The animals were injected with buffers without drug (group control) and with 0.5 mg/Kg of alendronate (experimental group) As much the alendronate as the control were administered in subcutaneous form, immediately later to the surgery, near the zone of work, in times 0, 7, 14 and 30 days. The parameters of study were Rx of the zone under study to the established times. All the animals were sacrificed by overdose with ether. The statistical analysis was made with Anova. the curved sample that to low concentrations the viability is greater to 98 percent, when increasing the concentration of the drug the cells begin to see themselves affected, but the viability never lowers of 70 percent, no matter how hard it is continued adding drug. The Rx both shows statistically significant differences (p=0,05) between groups, being observed bone formation as far as volume

Caracterização do uso de alendronato de sódio no tratamento de osteoporose por clínicos da rede privada de duas cidades do interior de São Paulo / Survey of the use of sodium alendronate in osteoporosis treatment by physicians in the private health system in two towns in São Paulo

O estudo mostrou como os clínicos da rede privada de Amparo e Pedreira, no interior do estado de São Paulo, utilizam o alendronato de sódio como recurso terapêutico na osteoporose. Esta enfermidade é de alta prevalência na população idosa, sendo tratada por médicos de diferentes especialidades. Este estudo, do tipo observacional, transversal e descritivo, foi realizado pormeio de entrevistas com 32 médicos para obtenção de dados sobre indicação, forma de utilização, seguimento de tratamento, medidas não farmacológicas e referencial teórico utilizado pelos entrevistados. Os resultadosmostraram que há concordância com o preconizado em consensos e guias terapêuticos em relação à indicação,doses recomendadas e medidas não farmacológicas, porém, foram verificadas falhas no seguimento dotratamento e na orientação dada ao paciente para a administração correta do medicamento, além de descrição imprecisa de fontes de informação. Concluiu-se que a atualização científica em fontes referenciais (ensaios randomizados controlados, metanálises) é indispensável para ajudar os clínicos na promoção do uso racional do alendronato de sódio no tratamento de osteoporose.

This is a study of how physicians working in the private health system in the towns of Amparo and Pedreira (upstate São Paulo, 75 miles away from the State capital) use sodium alendronate in the treatment of osteoporosis. This disease is highly prevalent in the elderly population and is treated by consultant clinicians/various specialities. The paper describes an observational, cross-sectional study that was carried out by interviewing 32 clinicians to evaluate: indication, usage, follow-up and evaluation of treatment, non pharmacological measures and source of information used by interviewees. The results show that clinical practice is in conformity with what is recommended in clinical guidelines and the general consensus, concerning indication, doses, and nonpharmacological measures. However, some faults were found in the course of treatment and in the advice given to the patients on how to take the drug, as well as imprecise descriptions of the sources of information by the doctors interviewed. It is concluded that constant scientific updating based on sources of reference (Randomized Controlled Trial, Meta- Analysis) is an indispensable aid to these clinicians in promoting the rational use of sodium alendronate inthe treatment of osteoporosis.

Ação local do alendronato sódico no processo de reparação óssea de fêmures de ratos espontaneamente hipertensos (SHR) / Local action of alendronate sodium on bone repair of spontaneously hypertensive rat (SHR) femurs

Este trabalho analisou a ação local do alendronato sódico no processo de reparação óssea em fêmures de ratos espontaneamente hipertensos (SHR). Foram utilizadosquarenta ratos machos e quarenta fêmeas, para a confecção de um defeito ósseo de 2,5mm de diâmetro. De acordo com o material utilizado, criaram-se quatro grupos: controle (C), amido (Am), alendronato 1mol (A1) e alendronato 2mol (A2). Os animais do grupo C não tiveram seus defeitos ósseos preenchidos. Após o período de sete e 21 dias, os animais foram sacrificados. Foi realizada a análise histológica e histomorfométrica e os dados submetidos à análise estatística ANOVA. Aos sete dias, encontrava-se tecido conjuntivo com hemorragia e infiltrado inflamatório ocupando a área do defeito em todos os grupos experimentais e, em alguns grupos, focos de matriz osteóide. Os animais dos grupos A1 e A2 apresentavam uma rede de fibrina no tecidoconjuntivo. Aos 21 dias, as trabéculas ósseas fechavam praticamente toda a extensão do defeito nos grupos C e Am. No grupo A1 de animais machos, observavam-setrabéculas que se irradiavam do interior da medula óssea até a área do defeito. Nos demais grupos A1 e A2 constatava-se apenas a presença de tecido conjuntivo, comdeposição de fibras colágenas e mínima deposição de matriz osteóide. Um achado histológico marcante foi a formação de tecido ósseo extra-cortical subperiosteal nosanimais dos grupos A1 e A2. O estudo concluiu que, neste modelo experimental, a administração local do alendronato sódico não contribuiu para o processo de reparação óssea nas concentrações molares utilizadas.