Vertebroplasty and kyphoplasty as treatment for osteoporotic vertebral fractures

Summary Over the last decade vertebroplasty and kyphoplasty have become popular as therapeutic options for the treatment of vertebral fractures. In fact, numerous non-controlled studies have indicated that both procedures are very efficacious for the control of pain associated with fractures. However, some recently published randomised trials have cast doubt on the true effectiveness of these procedures. On the other hand, certain observations have suggested that the increase in the rigidity which is produced by the injection of metacrylate into a vertebral body could facilitate the collapse of the adjacent vertebra. Therefore, vertebroplasty and kyphoplasty should not be considered as a routine theraputic measure, but should be limited to carefully selected patients, in whom the potential benefits surpass the risks and costs of the procedure. In any case, the patients should be put on a global treatment programme which includes pharmaceutical measures and non-pharmaceutical care to reduce the risk of future vertebral and peripheral fractures. Various clinical trials have recently been published which were supposed to be an important contribution to knowledge regarding the effectiveness of vertebroplasty. The results have been rather contradictory both within themselves, and with earlier observational studies. For this reason it is worth reviewing this questions with the intention of helping clinicians who need to take decisions on the treatment of patients with osteoporotic fractures. We have not dealt with the possible utility vertebroplasty in other processes, such as fractures caused by tumours or by trauma

Calidad de vida en pacientes con fosfatasa alcalina persistentemente baja portadores o no de mutaciones del gen ALPL

Introducción: Los niveles bajos de fosfatasa alcalina (FAlc) en suero son el sello distintivo de la hipofosfatasia, un trastorno debido a variantes patogénicas del gen ALPL. Nuestro objetivo fue determinar la calidad de vida relacionada con la salud en adultos con fosfatasa alcalina baja y explorar las diferencias entre pacientes con y sin mutaciones en ALPL. Material y métodos: Estudiamos 35 pacientes adultos con FAlc persistentemente baja en los que se excluyeron causas adquiridas y se secuenció ALPL. Se compararon con 35 controles de igual edad. Se completaron tres cuestionarios sobre dolor (Brief Pain Inventory, BPI), discapacidad física (Health Assessment Questionnaire Disability Index, HAQ-DI) y calidad de vida relacionada con la salud (36-item Short-Form Health Survey, SF-36). Resultados: Las puntuaciones medias de intensidad e interferencia del dolor en el BPI fueron mayores en el grupo de pacientes (p=0,04 y 0,004, respectivamente). Todos los dominios del instrumento HAQ tendieron a puntuar peor en los pacientes, con diferencias significativas en la puntuación de "alcance" (p=0,037) y la puntuación media general (0,23 frente a 0,09; p=0,029). Los pacientes puntuaron peor que los controles en varias dimensiones del SF-36 (rol físico, p=0,039; dolor corporal p=0,046; rol emocional, p=0,025). Sin embargo, los pacientes con y sin variantes patogénicas puntuaron de manera similar en todas las pruebas, sin diferencias significativas entre los grupos. Conclusiones: Los pacientes con niveles persistentemente bajos de FAlc tienen puntuaciones significativamente peores en dolor corporal y otras dimensiones de calidad de vida relacionadas con la salud, sin diferencias entre pacientes con y sin variantes patogénicas en el gen ALPL. Esto es consistente con la hipótesis de que estos últimos presenten mutaciones en regiones reguladoras, habitualmente no secuenciadas, del gen ALPL

Common variations in estrogen-related genes are associated with severe large-joint osteoarthritis: a multicenter genetic and functional study

OBJECTIVE: Several lines of evidence suggest that estrogens influence the development of osteoarthritis (OA). The aim of this study was to explore the association of two common polymorphisms within the aromatase (CYP19A1) and estrogen receptor (ER) alpha (ESR1) genes with severe OA of the lower limbs. METHODS: The rs1062033 (CYP19A1) and rs2234693 (ESR1) single nucleotide polymorphisms were genotyped in 5528 individuals (3147 patients with severe hip or knee OA, and 2381 controls) from four centres in Spain and the United Kingdom. Gene expression was measured in femoral bone samples from a group of patients. RESULTS: In the global analysis, both polymorphisms were associated with OA, but there was a significant sex interaction. The GG genotype at rs1062033 was associated with an increased risk of knee OA in women [odds ratio (OR) 1.23; P=0.04]. The CC genotype at rs2234693 tended to be associated with reduced OA risk in women (OR 0.76, P=0.028, for knee OA; OR=0.84, P=0.076 for hip OA), but with increased risk of hip OA in men (OR 1.28; P=0.029). Women with unfavourable genotypes at both loci had an OR of 1.61 for knee OA (P=0.006). The rs1062033 genotype associated with higher OA risk was also associated with reduced expression of the aromatase gene in bone. CONCLUSIONS: Common genetic variations of the aromatase and ER genes are associated with the risk of severe OA of the large joints of the lower limb in a sex-specific manner. These results are consistent with the hypothesis that estrogen activity may influence the development of large-joint OA

Analysis of Bone Histomorphometry in Rat and Guinea Pig Animal Models Subject to Hypoxia

Hypoxia may be associated with alterations in bone remodeling, but the published results are contradictory. The aim of this study was to characterize the bone morphometry changes subject to hypoxia for a better understanding of the bone response to hypoxia and its possible clinical consequences on the bone metabolism. This study analyzed the bone morphometry parameters by micro-computed tomography (?CT) in rat and guinea pig normobaric hypoxia models. Adult male and female Wistar rats were exposed to chronic hypoxia for 7 and 15 days. Additionally, adult male guinea pigs were exposed to chronic hypoxia for 15 days. The results showed that rats exposed to chronic constant and intermittent hypoxic conditions had a worse trabecular and cortical bone health than control rats (under a normoxic condition). Rats under chronic constant hypoxia were associated with a more deteriorated cortical tibia thickness, trabecular femur and tibia bone volume over the total volume (BV/TV), tibia trabecular number (Tb.N), and trabecular femur and tibia bone mineral density (BMD). In the case of chronic intermittent hypoxia, rats subjected to intermittent hypoxia had a lower cortical femur tissue mineral density (TMD), lower trabecular tibia BV/TV, and lower trabecular thickness (Tb.Th) of the tibia and lower tibia Tb.N. The results also showed that obese rats under a hypoxic condition had worse values for the femur and tibia BV/TV, tibia trabecular separation (Tb.Sp), femur and tibia Tb.N, and BMD for the femur and tibia than normoweight rats under a hypoxic condition. In conclusion, hypoxia and obesity may modify bone remodeling, and thus bone microarchitecture, and they might lead to reductions in the bone strength and therefore increase the risk of fragility fracture.Funding: The present study was supported by grant reference BFU2015-70616-R from MINECOFEDER (Spain Government) and Programa Estratégico IBGM, Escalera de Excelencia, Ref. CCVC8485, Consejería de Educacion, JCyL (Spain)

Association of aromatase and estrogen receptor gene polymorphisms with hip fractures

Producción CientíficaSummary Two polymorphisms of the aromatase and estrogen receptor genes appeared to interact to influence the risk of hip fractures in women. Introduction Allelic variants of the aromatase gene have been associated with bone mineral density and vertebral fractures. Our objective was to analyze the relationship between two polymorphisms of the aromatase and estrogen receptor genes and hip fracture

The cerebellum ages slowly according to the epigenetic clock

Studies that elucidate why some human tissues age faster than others may shed light on how we age, and ultimately suggest what interventions may be possible. Here we utilize a recent biomarker of aging (referred to as epigenetic clock) to assess the epigenetic ages of up to 30 anatomic sites from supercentenarians (subjects who reached an age of 110 or older) and younger subjects. Using three novel and three published human DNA methylation data sets, we demonstrate that the cerebellum ages more slowly than other parts of the human body. We used both transcriptional data and genetic data to elucidate molecular mechanisms which may explain this finding. The two largest superfamilies of helicases (SF1 and SF2) are significantly over-represented (p=9.2x10-9) among gene transcripts that are over-expressed in the cerebellum compared to other brain regions from the same subject. Furthermore, SNPs that are associated with epigenetic age acceleration in the cerebellum tend to be located near genes from helicase superfamilies SF1 and SF2 (enrichment p=5.8x10-3). Our genetic and transcriptional studies of epigenetic age acceleration support the hypothesis that the slow aging rate of the cerebellum is due to processes that involve RNA helicases

Differential analysis of genome-wide methylation and gene expression in mesenchymal stemcells of patients with fractures and osteoarthritis

Insufficient activity of the bone-forming osteoblasts leads to low bone mass and predisposes to fragility fractures. The functional capacity of human mesenchymal stem cells (hMSCs), the precursors of osteoblasts, may be compromised in elderly individuals, in relation with the epigenetic changes associated with aging. However, the role of hMSCs in the pathogenesis of osteoporosis is still unclear. Therefore, we aimed to characterize the genome-wide methylation and gene expression signatures and the differentiation capacity of hMSCs from patients with hip fractures. We obtained hMSCs from the femoral heads of women undergoing hip replacement due to hip fractures and controls with hip osteoarthritis. DNA methylation was explored with the Infinium 450K bead array. Transcriptome analysis was done by RNA sequencing. The genomic analyses revealed that most differentially methylated loci were situated in genomic regions with enhancer activity, distant from gene bodies and promoters. These regions were associated with differentially expressed genes enriched in pathways related to hMSC growth and osteoblast differentiation. hMSCs from patients with fractures showed enhanced proliferation and upregulation of the osteogenic drivers RUNX2/OSX. Also, they showed some signs of accelerated methylation aging. When cultured in osteogenic medium, hMSCs from patients with fractures showed an impaired differentiation capacity, with reduced alkaline phosphatase activity and poor accumulation of a mineralized matrix. Our results point to 2 areas of potential interest for discovering new therapeutic targets for low bone mass disorders and bone regeneration: the mechanisms stimulating MSCs proliferation after fracture and those impairing their terminal differentiation

Análisis de la morfometría ósea en ratas sometidas a diferentes situaciones de hipoxia

El hueso es uno de los tejidos metabólicamente más activos, metabolismo que requiere de un aporte suficiente de oxígeno. En este sentido, se han publicado resultados contradictorios de cómo la hipoxia podría modificar el remodelado óseo y con ello la estructura del hueso. El objetivo del estudio fue valorar el efecto de la hipoxia sobre la morfometría ósea y la densidad mineral ósea medidas por tomografía axil computarizada de alta resolución (HR-pQTc ). Se analizaron 61 ratas wistar a las que se les sometió a diferentes condiciones experimentales: ratas control (sometidas a condiciones de normoxia), ratas sometidas a hipoxia crónica constante y ratas sometidas a hipoxia crónica intermitente. Los animales se sacrificaron por una sobredosis cardiaca de fenobarbital. A continuación, se procedió a la extracción de los huesos, fémur y tibia. Posteriormente se fijaron en etanol al 70% para su posterior análisis. Se utilizó un micro-TAC modelo escáner SKYSCAN 1172 de la marca BRUKER y un software de captación de datos skyscan1172 µCT. La reconstrucción de las imágenes se realizó mediante un software Nrecon utilizándose posterio mente el software de análisis de imagen "CTAN". Se utilizó el SPSS v22 para el análisis estadístico. Nuestros resultados mostraron que las ratas sometidas a condiciones de hipoxia tenían una menor densidad mineral de tejido (TMD) en fémur cortical y un menor grosor trabecular de la tibia. Por otra parte, analizando las ratas sometidas a hipoxia crónica permanente en referencia a las ratas control, se observó que la hipoxia se asoció con un menor espesor cortical de la tibia, menor densidad mineral ósea (BMD) en fémur trabecular y con menor volumen óseo porcentual (BV/TV) del fémur trabecular. Diferenciando por sexos, las ratas hembras sometidas a hipoxia crónica permanente presentaron un menor espesor de la tibia cortical, menor grosor de las trabéculas de la tibia y el fémur y menores valores de BMD en las trabéculas de la tibia y el fémur. Las ratas macho sometidas a hipoxia crónica permanente, tenían un menor número de trabéculas en la tibia. También se observó como las ratas sometidas a hipoxia permanente intermitente, tenían un menor TMD que las ratas control. Nuestros resultados mostraron que en diferentes condiciones de hipoxia se observó un deterioro de la morfometría ósea, probablemente debido a que se produce una alteración del remodelado óseo promovido por la hipoxia tisular