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2.
Bone ; 133: 115224, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31923705

RESUMEN

Four heterozygous in-frame tandem duplications of different lengths in TNFRSF11A, the gene that encodes receptor activator of nuclear factor κB (RANK), constitutively activate RANK and lead to high turnover skeletal disease. Each duplication elongates the signal peptide of RANK. The 18-base pair (bp) duplication at position 84 (84dup18) causes familial expansile osteolysis (FEO), the 15-bp duplication at position 84 (84dup15) causes expansile skeletal hyperphosphatasia (ESH), the 12-bp duplication at position 90 (90dup12) causes panostotic expansile bone disease (PEBD), and the 27-bp duplication causes early-onset Paget's disease of bone (PDB2). The severity of the associated skeletal disease seems inversely related to the duplication's length. Additional 15- and 18-bp duplications of TNFRSF11A fit this pattern. Herein, we delineate the skeletal disease of a middle-aged man of Mexican descent who we found to harbor a novel 27-bp tandem duplication at position 77 (77dup27) of TNFRSF11A. His disorder shares features, particularly hand involvement, with the single Japanese (75dup27) and Chinese (78dup27) kindreds with PDB2 (PDB2Jpn and PDB2Chn, respectively). However, his distinct hearing loss developed later in adulthood compared to the other 27-bp families. He reported no morbidities during childhood, but in his late 20s developed unexplained tooth loss, low-trauma fractures, post-operative hypercalcemia, and painless enlargement of his fingers. Biochemical studies showed elevated serum alkaline phosphatase (ALP), bone-specific ALP, C-telopeptide, and osteocalcin consistent with rapid bone remodeling. Radiologic imaging revealed remarkably lucent bones with vertebral compression fractures, calvarial lucencies, and thinned long bone cortices. DXA showed extremely low bone mineral density. His disorder genetically and phenotypically fits best with PDB2 and can be called PDB2Mex.


Asunto(s)
Fracturas por Compresión , Osteítis Deformante , Osteólisis , Fracturas de la Columna Vertebral , Adulto , Humanos , Masculino , Persona de Mediana Edad , Osteítis Deformante/genética , Ligando RANK/genética , Receptor Activador del Factor Nuclear kappa-B/genética
3.
Diabetes Metab Syndr Obes ; 12: 2419-2431, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31819568

RESUMEN

PURPOSE: To describe clinical, biochemical and anthropometric profiles in adults with class III obesity classified as metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUHO). PATIENTS AND METHODS: This is a cross-sectional study with patients classified as MHO and MUHO according to the NCEP-ATP III. Anthropometric, biochemical and clinical variables were analyzed. RESULTS: A total of 223 subjects were evaluated and 32.73% were classified as MHO and 67.26% as MUHO, respectively. The insulin resistance homeostasis model (HOMA-IR) showed elevation in the MUHO group (p=0.003) and anthropometric variables were correlated with bone markers [body index mass (BMI) vs phosphorus: r=0.31, p<0.001; BMI vs 25(OH)D: r=-0.31, p=0.041]. Visceral adiposity index was lower in MHO (p=0.001). Negative correlations between inflammatory markers and bone markers were observed in the MHO group (calcium vs C-reactive protein: -0.30, p=0.017; parathyroid hormone vs HOMA-IR: r=-0.28, p=0.017. CONCLUSION: MHO individuals showed important metabolic changes, such as those observed in MUHO, despite lower prevalence and severity. Continuous monitoring of these individuals is suggested, given the transient nature of the MHO phenotype.

4.
Calcif Tissue Int ; 104(6): 650-657, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30790003

RESUMEN

Gaucher disease (GD) is the most prevalent lysosomal storage disease, and bone involvement is the most disabling condition. The aim of the present study was to evaluate bone involvement in adult patients with GD, using an observational cross-sectional study. Patients were evaluated using X-rays, bone densitometry (BMD), trabecular bone score (TBS), magnetic resonance imaging (MRI), and biochemical bone markers. Thirty-two type 1GD patients were included (mean age: 40 ± 16 years). Patients had received velaglucerase for 2.7 ± 1.4 years; 19/32 had been treated previously with imiglucerase. Ninety-four percent of subjects met therapeutic goals for hematological parameters, and eight were splenectomized (SPX). Nineteen patients had irreversible bone lesions (IL), i.e., avascular necrosis, bone infarction, and/or vertebral fractures. MRI showed marrow infiltration in 71% of patients. Patients with IL had higher bone marrow burden than those without (p = 0.001). All SPX patients had IL, a higher prevalence of bone marrow edema (p = 0.02), and lower TBS (p = 0.03) than non-SPX patients. Only 18.7% of patients had abnormal BMD, with no correlation with fractures (FX). TBS values were < 1350 in 53% of patients and tended to be lower in those with FX (p = 0.06). Patients with P1NP in the lower quartile had lower TBS (p = 0.03) than those with P1NP in the higher quartiles. TBS correlated moderately but not significantly with P1NP (r = 0.32) and BMB (r = - 0.44). A high prevalence of IL was documented. Bone quality was more affected than BMD in fracture patients. Low bone formation, active bone marrow infiltration, and splenectomy might be implicated in IL.


Asunto(s)
Enfermedades Óseas/diagnóstico , Enfermedades Óseas/epidemiología , Enfermedades Óseas/etiología , Enfermedad de Gaucher/complicaciones , Enfermedad de Gaucher/epidemiología , Absorciometría de Fotón , Adulto , Anciano , Argentina/epidemiología , Densidad Ósea , Estudios Transversales , Femenino , Enfermedad de Gaucher/diagnóstico , Humanos , Vértebras Lumbares , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Radiografía , Fracturas de la Columna Vertebral/diagnóstico , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/etiología , Adulto Joven
5.
Int Endod J ; 51(8): 889-900, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29377189

RESUMEN

AIM: To investigate the relationship between diabetes mellitus and local/systemic effects of both grey and white mineral trioxide aggregate (MTA) Angelus on bone marker expression. METHODOLOGY: Wistar rats were divided into two groups: healthy and diabetic (Alloxan induced), which were further divided into three subgroups (control, GMTA Angelus and WMTA Angelus). Polyethylene tubes filled with MTA materials or empty tubes were implanted in dorsal connective tissue. On days 7 and 30, blood samples were collected for calcium, phosphorus and ALP measurement. The animals were euthanized; implanted tubes were removed and processed for immunohistochemical analysis of osteocalcin (OCN) and osteopontin (OPN). Kruskal-Wallis followed by Dunn's multiple comparison test was performed for nonparametric data, and anova followed by Tukey's test for parametric data. RESULTS: No difference in systemic serum calcium levels between both groups was observed. On day 7, serum phosphorus levels within the WMTA healthy group were higher than that of the diabetic group. On day 30, healthy rats exhibited lower phosphorus levels than diabetic ones. At both time points, the diabetic group was associated with more ALP activity than the healthy group. Immunohistochemical analyses of the healthy group revealed OCN- and OPN-positive cells in the presence of both MTA materials. However, under diabetic conditions, both OCN and OPN were absent. CONCLUSION: Both MTA materials were associated with an increase in serum calcium, phosphorus and ALP, suggesting a potential systemic effect, along with triggered differentiation of OCN- and OPN-positive cells. Moreover, in diabetic conditions, an inhibitory effect on MTA-induced differentiation of OCN- and OPN-positive cells was detected.


Asunto(s)
Compuestos de Aluminio/análisis , Compuestos de Calcio/análisis , Diabetes Mellitus Experimental/metabolismo , Óxidos/análisis , Silicatos/análisis , Animales , Diabetes Mellitus Experimental/sangre , Combinación de Medicamentos , Inmunohistoquímica , Osteocalcina/análisis , Osteopontina/análisis , Ratas , Ratas Wistar
6.
Phytother Res ; 32(1): 58-64, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29027270

RESUMEN

Nutritional factors have been associated with osteoporosis and fractures. The intake of coffee may increase the risk of fracture whereas the intake of black and green tea is associated with its reduction. Recently, consumption of yerba mate was associated with increased bone mineral density in postmenopausal women. Nonetheless, its influence on fracture is not known. The aim of this study was to evaluate the effect of yerba mate tea intake on fractures, bone markers, calcium homeostasis, and oxidative stress in postmenopausal women. A case-control study was carried out in South Brazil, 46 women with fractures and 49 controls completed the study. There was no significant difference between the frequency of fractures in women who drank mate tea and women who did not (48.3% vs. 48.5%, p = .99). Moreover, there was no significant difference concerning the serum levels of total calcium, phosphorus, PTH, vitamin D, P1NP, and CTX in the subjects with the history of yerba mate use when compared to controls. Higher serum levels of NOx were found in women who drank the yerba mate infusion. In conclusion, the yerba mate intake is not associated with fracture, and it appears to have a neutral effect on the bone metabolism.


Asunto(s)
Huesos/efectos de los fármacos , Ilex paraguariensis/química , Osteoporosis/prevención & control , Extractos Vegetales/química , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia
7.
Actual. osteol ; 13(1): 28-36, Ene - Abr. 2017. tab
Artículo en Español | LILACS | ID: biblio-1118788

RESUMEN

El pico de masa ósea (PMO) se alcanza entre los 20 y 35 años, pero la aposición ósea continúa hasta alcanzar el pico de fortaleza ósea (PFO). Se crea así una ventana entre ambos picos que podría ser evaluada mediante marcadores bioquímicos de recambio óseo, ya que durante dicho período la densidad mineral permanece constante. El objetivo fue determinar el final de la aposición ósea mediante marcadores bioquímicos óseos. Se evaluaron por décadas entre 20 y 49 años de edad 139 sujetos sanos de ambos sexos (69 hombres y 70 mujeres), determinando fosfatasa alcalina ósea (FAO), osteocalcina (OC), propéptido amino terminal del colágeno tipo 1 (P1NP) y telopéptido C-terminal del colágeno tipo 1 (CTX). Los marcadores correlacionan negativamente con la edad (OC: r= -0,3; p<0,01; P1NP: r= -0,4; p< 0,01 y CTX: r= -0,4; p<0,01), exceptuando FAO. En hombres de 20-29 años, P1NP y el CTX fueron significativamente mayores vs. 30-39 años (p<0,05 y p<0,001, respectivamente), y entre 30-39 años vs. de 40-49 años en P1NP y CTX (p<0,05; p<0,001, respectivamente). En mujeres de 20-29 años, P1NP y CTX fueron significativamente mayores vs. 30-39 años (p<0,0001 y p<0,01, respectivamente). Conclusión: los marcadores de remodelado óseo más sensibles y específicos permitirían determinar bioquímicamente el fin de la aposición ósea que se produce entre el PMO y el PFO. Si bien es necesario ampliar el número de sujetos evaluados, los datos que surgen de la presente investigación sentarían las bases para futuros estudios epidemiológicos referidos al fin de la aposición ósea. (AU)


Peak bone mass is achieved between 20-35 years; however bone apposition continues to reach an optimal skeleton strength. The window between peak bone mass and peak bone apposition may be evaluated by biochemical bone turnover markers. The objective of this study was to determine the end of bone apposition through biochemical bone markers in both sexes. A total of 139 subjects (69 men and 70 women) were divided by decades between 20 and 49 years of age. Bone alkaline phosphatase (BAL), osteocalcin (OC), type I collagen propeptide (P1NP) and type I collagen C-terminal telopeptide (CTX) were evaluated. Except BAL, the other bone markers negatively correlated with the age [OC (r= -0.3; p<0.01); P1NP (r= -0.4; p<0.01) and CTX (r= -0.4; p<0.01)]. Regarding men aged 20 to 29 years, P1NP and CTX were significantly higher vs. 30-39 years (p<0.05 y p<0.001, respectively) and. vs. 40-49 years (p<0.05; p<0.001, respectively). In women, the results were similar. Regarding 20-29 years, P1NP and CTX were higher vs. 30-39 years (p<0.001 y p<0.01, respectively). Bone remodeling rate decreases after the third decade, suggesting the end of the apposition period of peak bone mass. Conclusion: The most specific and sensitive bone markers would biochemically determine the end of bone apposition that extends between the peak of bone mass and the peak of bone strength. Although it is necessary to increase the number of subjects evaluated, the data that emerge from the present study would establish the bases for future epidemiological studies referring to the end of bone apposition. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Adulto Joven , Resorción Ósea/fisiopatología , Biomarcadores , Osteoblastos/fisiología , Osteoclastos/fisiología , Osteogénesis/fisiología , Huesos/metabolismo , Densidad Ósea/fisiología , Osteocalcina/sangre , Calcio/sangre , Factores de Edad , Remodelación Ósea/fisiología , Creatinina/sangre , Colágeno Tipo I/biosíntesis , Colágeno Tipo I/sangre , Densitometría , Fosfatasa Alcalina/sangre , Fracturas Osteoporóticas/prevención & control
8.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;50(3): 407-421, set. 2016. ilus, graf, tab
Artículo en Español | LILACS | ID: biblio-837618

RESUMEN

Los marcadores óseos son moléculas específicas que pueden clasificarse en dos categorías: formación y resorción óseas. Cuando se los compara con los adultos, los niños tienen muy elevadas concentraciones de los marcadores óseos debido a la elevada velocidad de crecimiento y a la rápida remodelación ósea. No solo reflejan el crecimiento (modelación esquelética y crecimiento linear), sino también la remodelación ósea. Ningún marcador es específico para cada uno de estos procesos y no son fáciles de interpretar en niños y adolescentes dado que están influenciados por varios factores fisiológicos como edad, sexo, velocidad de crecimiento y estadio puberal. Es necesario conocer la velocidad de crecimiento y el desarrollo puberal para interpretar correctamente los resultados. Además, muestran variaciones diurnas en sus concentraciones con picos por la mañana y nadir por la tarde. A la actualidad, existe una variada referencia de datos de marcadores óseos en niños y adolescentes. Se presenta una revisión de hallazgos científicos de varios marcadores séricos y urinarios que reflejan la formación y resorción óseas durante la niñez y adolescencia. Los marcadores óseos son de mucha utilidad en investigación clínica y fisiología del metabolismo óseo, sin embargo, su uso de rutina en clínica aún no está bien establecido.


Bone markers are specific bone-derived molecules that can be classified into two categories: bone formation and bone resorption markers. Compared to adults, children have dramatically elevated bone marker concentrations due to high skeletal growth velocity and rapid bone turnover. They reflect growth (skeletal modelling) and remodelling and no marker is specific for any of the different biological processes of remodelling, modelling or epiphyseal growth. Bone turnover markers may not be easy to interpret in children as they are influenced by many physiological factors, such as age, gender, growth velocity, and pubertal stage. Knowledge of growth velocity and pubertal development is necessary to interpret the values of biological markers of bone turnover correctly. Turnover markers also show a diurnal variation, with a peak of concentrations in the morning and nadir of concentrations in the late afternoon. To date, a variety of pediatric references for bone markers have been reported. This review describes research findings on various sera and urine markers that reflect bone formation and resorption in children and adolescents. While bone markers are useful in research in the field of bone metabolism, their utility in routine clinical applications in pediatrics has not been established.


Marcadores ósseos são moléculas específicas que podem ser classificadas em duas categorias: formação e reabsorção óssea. Em comparação com os adultos, as crianças têm concentrações altamente elevadas de marcadores ósseos devido à alta velocidade de crescimento e à remodelação óssea rápida. Não só refletem o crescimento (modelagem esquelética e crescimento linear), mas também a remodelação óssea. Nenhum marcador é específico para cada um desses processos e não são fáceis de interpretar em crianças e adolescentes visto que estão influenciados por vários fatores fisiológicos, tais como idade, sexo, velocidade de crescimento e desenvolvimento púbere. É necessário o conhecimento da velocidade de crescimento e o desenvolvimento do púbere para interpretar corretamente os resultados. Além disso, mostram variações diurnas em suas concentrações com picos de manhã e nadir pela tarde. Atualmente, existe uma variada referência de dados de marcadores ósseos em crianças e adolescentes. Apresenta-se uma revisão de achados científicos de vários marcadores séricos e urinários que refletem a formação e reabsorção ósseas em crianças e adolescentes. Embora os marcadores ósseos sejam úteis na investigação clínica e fisiologia do metabolismo ósseo, sua utilidade em aplicações clínicas de rotina ainda não foi bem estabelecida.


Asunto(s)
Humanos , Niño , Adolescente , Resorción Ósea , Osteogénesis , Biomarcadores , Pediatría
9.
Rev. argent. endocrinol. metab ; Rev. argent. endocrinol. metab;52(4): 198-203, set. 2015.
Artículo en Español | LILACS | ID: biblio-957933

RESUMEN

La Modelación y el Remodelado de hueso son llevados a cabo a través del proceso de Recambio Óseo en sitios específicos llamados Unidades de Remodelación Ósea (URO). Este proceso puede evaluarse a través de marcadores bioquímicos de Formación y de Resorción que reflejan cambios globales del metabolismo esquelético. Estos marcadores de remodelado óseo son utilizados para investigación de enfermedades óseo-metabólicas, porque proveen información dinámica del metabolismo del hueso y pueden ser cuantificados en suero o en orina. La variación de estos marcadores se deben principalmente a variables preanalíticas, analíticas y biológicas y debe interpretarse teniendo en cuenta el Valor de Referencia para el Cambio significativo (VRC), que resulta de un cálculo en el que intervienen la variabilidad biológica (VB) del analito y el error aleatorio del método utilizado en el laboratorio.


The Modeling and Remodeling processes are conducted through the process of replacement bone at specific sites called Units Bone Remodeling (URO).These can be evaluated by biochemical markers of formation and resorption that reflect changes in skeletal metabolism. These markers of bone turnover are used for research óseo-metabolic diseases because they provide dynamic information of bone metabolism and can be quantified in serum or urine. The variation of these markers is mainly due to preanalytical, analytical and biological variables and should be interpreted taking into account the Reference Value Change (VRC), which results from a calculation in which the biological variability (VB) of the analyte and the random error of the method used in the laboratory are involved.

10.
Arq. bras. endocrinol. metab ; Arq. bras. endocrinol. metab;58(5): 504-513, 07/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-719203

RESUMEN

Several factors are involved in determining bone quality including bone density, bone turnover, the extent of trabecular bone connectivity, cortical porosity and geometry. Metabolically active and in a continuous process of remodeling, approximately 20% of bone tissue is renewed annually. Bone turn over markers (BTM) are frequently used in clinical trials and to provide valid information about the effectiveness of osteoporosis treatment, reflecting the state of bone metabolism and its response to treatment, although they are not useful alone to estimate bone loss. In this review the behavior of BTM from different clinical trials or different osteoporotic drugs will be addressed.


Diversos fatores estão envolvidos na determinação da qualidade óssea, incluindo a densidade óssea, a remodelação óssea, a extensão da conectividade do osso trabecular, porosidade cortical e geometria. Metabolicamente ativo e, em um processo contínuo de remodelação, cerca de 20% do tecido ósseo é renovado anualmente. Por sua vez, marcadores de turnover ósseo (BTM) são frequentemente utilizados em estudos clínicos e fornecem informações válidas sobre a eficácia do tratamento da osteoporose, o que reflete o metabolismo ósseo e sua resposta ao tratamento, embora eles não sejam úteis somente para estimar a perda óssea. Nesta revisão, o comportamento dos BTM em ensaios clínicos diferentes e com diferentes drogas osteoporóticas será abordado.

11.
Araçatuba; s.n; 2014. 75 p. graf, ilus.
Tesis en Portugués | BBO - Odontología | ID: biblio-867099

RESUMEN

Células-tronco mesenquimais (CTMs) obtidas a partir da medula óssea são capazes de se diferenciarem, sobretudo, em condrócitos, adipócitos e osteoblastos. Durante a osteogênese in vitro, alguns parâmetros são utilizados para caracterizar este processo, tais como atividade da fosfatase alcalina (FAL), mineralização e expressão de proteínas associadas à osteoblastos. Ratos espontaneamente hipertensos (SHR) são um modelo animal de hipertensão essencial humana e desenvolvem hipertensão após 4 semanas de idade. Esta linhagem apresenta alterações significativas no metabolismo ósseo. O objetivo do presente estudo foi investigar se, o genótipo hipertensivo poderia interferir na diferenciação osteoblástica das CTMs de ratos SHR e qual mecanismo está alterado quando comparadas com a linhagem progenitora, ratos Wistar. Para isso, nós obtivemos CTMs da medula óssea de ratos Wistar e SHR com 4 semanas de idade, sem a hipertensão estabelecida, afim de avaliar somente o possível efeito do genótipo hipertensivo na diferenciação osteogênica in vitro. Nós induzimos, ou não, a diferenciação osteogênica in vitro por meio da utilização dos indutores osteogênicos: ácido ascórbico, β-glicerofosfato e dexametasona. Os resultados demonstraram que, CTMs indiferenciadas de SHR (SHRC) demonstraram taxa de proliferação aumentada em comparação a CTMs, na mesma condição, de Wistar (WC), e após a indução da osteogênica, a taxa de proliferação apresentou uma diminuição acentuada no grupo SHR (SHRMO) do que no grupo Wistar na mesma condição (WMO). Embora não fora observada diferença significativa na atividade da FAL entre SHRMO e WOM no 7° dia, a mineralização e a diferenciação osteoblástica foram menores no grupo SHRMO no mesmo período experimental. Os fatores de transcrição Osterix e β-catenina parecem estar envolvidos na diferenciação reduzida no grupo SHRMO, pois apresentaram menor expressão neste grupo experimental. Além disso, a expressão diminuída de proteínas associadas a...


Mesenchymal stem cells (MSCs) from bone marrow are able to differentiate mainly into chondrocytes, adipocytes and osteoblasts. During in vitro osteogenesis, some parameters are used to characterize this process, such as the activity of alkaline phosphatase (ALP), mineralization and osteoblast-associated proteins expression. Spontaneously hypertensive rats (SHR) is an animal model of human essential hypertension. This animals developing hypertension after 4 weeks of age. This strain shows significant changes in bone metabolism. The aim of this study was to investigate whether the hypertensive genotype could influence the osteoblastic differentiation of MSCs from SHR and which mechanism are altered when compared to the parental strain, Wistar rats. For that, we have obtained bone marrow MSCs from Wistar and SHR rats at 4 weeks of age, without hypertension established in order to evaluate only the possible effect of hypertensive genotype on osteogenic differentiation in vitro. We induced or non-osteogenic differentiation in vitro using osteogenic inducers: ascorbic acid, dexamethasone and β-glycerophosphate. The results demonstrate that undifferentiated MSCs SHR (SHRC) showed increased proliferation rate compared to MSCs, in the same condition Wistar (WC) and after osteogenic induction, proliferation rate showed a marked decrease in SHR (SHRMO) than in Wistar group in the same condition (WMO). Although it was not observed significant difference in ALP activity between WMO and SHRMO on day 7, mineralization and osteoblast differentiation were lower on group SHRMO in the same experimental period. The transcription factors Osterix and β-catenin appear to be involved in reduced differentiation in SHRMO group because they showed lower expression in this experimental group. Furthermore, the decreased osteoblast-associated proteins such as OCN, BSP, OPN expression suggest that extracellular matrix SHRMO group has a lower quality in comparison to WMO group. Higher...


Asunto(s)
Animales , Ratas , Hipertensión , Células Madre Mesenquimatosas , Osteoblastos , Ratas Endogámicas SHR , Ratas Wistar
12.
Araçatuba; s.n; 2014. 75 p. graf, ilus.
Tesis en Portugués | LILACS | ID: lil-755432

RESUMEN

Células-tronco mesenquimais (CTMs) obtidas a partir da medula óssea são capazes de se diferenciarem, sobretudo, em condrócitos, adipócitos e osteoblastos. Durante a osteogênese in vitro, alguns parâmetros são utilizados para caracterizar este processo, tais como atividade da fosfatase alcalina (FAL), mineralização e expressão de proteínas associadas à osteoblastos. Ratos espontaneamente hipertensos (SHR) são um modelo animal de hipertensão essencial humana e desenvolvem hipertensão após 4 semanas de idade. Esta linhagem apresenta alterações significativas no metabolismo ósseo. O objetivo do presente estudo foi investigar se, o genótipo hipertensivo poderia interferir na diferenciação osteoblástica das CTMs de ratos SHR e qual mecanismo está alterado quando comparadas com a linhagem progenitora, ratos Wistar. Para isso, nós obtivemos CTMs da medula óssea de ratos Wistar e SHR com 4 semanas de idade, sem a hipertensão estabelecida, afim de avaliar somente o possível efeito do genótipo hipertensivo na diferenciação osteogênica in vitro. Nós induzimos, ou não, a diferenciação osteogênica in vitro por meio da utilização dos indutores osteogênicos: ácido ascórbico, β-glicerofosfato e dexametasona. Os resultados demonstraram que, CTMs indiferenciadas de SHR (SHRC) demonstraram taxa de proliferação aumentada em comparação a CTMs, na mesma condição, de Wistar (WC), e após a indução da osteogênica, a taxa de proliferação apresentou uma diminuição acentuada no grupo SHR (SHRMO) do que no grupo Wistar na mesma condição (WMO). Embora não fora observada diferença significativa na atividade da FAL entre SHRMO e WOM no 7° dia, a mineralização e a diferenciação osteoblástica foram menores no grupo SHRMO no mesmo período experimental. Os fatores de transcrição Osterix e β-catenina parecem estar envolvidos na diferenciação reduzida no grupo SHRMO, pois apresentaram menor expressão neste grupo experimental. Além disso, a expressão diminuída de proteínas associadas...


Mesenchymal stem cells (MSCs) from bone marrow are able to differentiate mainly into chondrocytes, adipocytes and osteoblasts. During in vitro osteogenesis, some parameters are used to characterize this process, such as the activity of alkaline phosphatase (ALP), mineralization and osteoblast-associated proteins expression. Spontaneously hypertensive rats (SHR) is an animal model of human essential hypertension. This animals developing hypertension after 4 weeks of age. This strain shows significant changes in bone metabolism. The aim of this study was to investigate whether the hypertensive genotype could influence the osteoblastic differentiation of MSCs from SHR and which mechanism are altered when compared to the parental strain, Wistar rats. For that, we have obtained bone marrow MSCs from Wistar and SHR rats at 4 weeks of age, without hypertension established in order to evaluate only the possible effect of hypertensive genotype on osteogenic differentiation in vitro. We induced or non-osteogenic differentiation in vitro using osteogenic inducers: ascorbic acid, dexamethasone and β-glycerophosphate. The results demonstrate that undifferentiated MSCs SHR (SHRC) showed increased proliferation rate compared to MSCs, in the same condition Wistar (WC) and after osteogenic induction, proliferation rate showed a marked decrease in SHR (SHRMO) than in Wistar group in the same condition (WMO). Although it was not observed significant difference in ALP activity between WMO and SHRMO on day 7, mineralization and osteoblast differentiation were lower on group SHRMO in the same experimental period. The transcription factors Osterix and β-catenin appear to be involved in reduced differentiation in SHRMO group because they showed lower expression in this experimental group. Furthermore, the decreased osteoblast-associated proteins such as OCN, BSP, OPN expression suggest that extracellular matrix SHRMO group has a lower quality in comparison to WMO group. Higher...


Asunto(s)
Animales , Ratas , Hipertensión , Células Madre Mesenquimatosas , Osteoblastos , Ratas Endogámicas SHR , Ratas Wistar
13.
Braz. arch. biol. technol ; Braz. arch. biol. technol;53(1): 193-201, Jan.-Feb. 2010. tab, ilus
Artículo en Inglés | LILACS | ID: lil-543206

RESUMEN

In the present clinical study, the effect of oligofructose-enriched inulin was studied on bone metabolism in girls from 9 to 12 years old, with low habitual calcium intakes, who attended public schools. Two calcium-enriched formulations, supplemented with oligofructose-enriched inulin (test drink) or without (standard drink) were made. Sixty pre-pubertal girls were randomized into a double-blind and crossover design, divided into three groups and received one daily portion of either the standard drink (group 1) or test drink (group 2) during 11 weeks, followed by a three-week washout period. Group control did not receive any supplementation. Biochemical evaluations of serum calcium, intact parathyroid hormone - iPTH - and bone alkaline phosphatase - BAP - were performed at baseline and after 4, 8 and 11 weeks of each intervention period. In group 1, a significant increase in serum calcium and BAP and a reduction of iPTH were observed after consumption of the test drink.


No presente ensaio clínico, o efeito de oligofrutose enriquecida com inulina foi estudado no metabolismo ósseo de meninas de 9 a 12 anos com baixa ingestão habitual de cálcio, matriculadas em escolas públicas. Duas formulações foram suplementadas ou não (bebida padrão) com oligofrutose enriquecida com inulina (bebida teste). Sessenta meninas pré-púberes foram aleatorizadas em estudo duplo cego crossover e divididas em três grupos e receberam uma porção diária da bebida padrão (grupo 1) ou teste (grupo 2) durante 11 semanas, seguidos por um período de intervalo de três semanas. O grupo controle não recebeu nenhuma suplementação. As avaliações bioquímicas de cálcio sérico, paratormônio intacto - PTHi e fosfatase alcalina fração óssea - FAO foram executadas ao início e após 4, 8 e 11 semanas de cada período de intervenção. No grupo 1, um aumento significante no cálcio sérico e FAO e uma redução no PTHi foram observadas após o consumo da bebida teste.

14.
Curr Ther Res Clin Exp ; 70(2): 161-72, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24683227

RESUMEN

BACKGROUND: Limited information is available about long-term pamidronate treatment in adults with fibrous dysplasia (FD) of bone. OBJECTIVE: The aim of this case series was to report the clinical outcomes and the biochemical and densitometric findings in a group of young adult patients with polyostotic FD treated for ≥3 years with IV pamidronate. METHODS: Pamidronate was administered every 6 months (60 mg/d for 3 days) for 2 years. Thereafter, treatment was individualized. Pamidronate was administered at shorter or longer intervals based on response. Bone pain, radiography, serum bone alkaline phosphatase (BALP) activity, and urinary C-terminal cross-linking telopep-tide of type I collagen (CTX-I) concentration were assessed for a mean of 7 years. Bone mineral density (BMD) of FD areas (FDas) and contralateral areas (CLas) were measured at baseline and at 12 and 24 months. Data were collected prospectively. RESULTS: Seven patients (5 women, 2 men; mean [SD] age, 31.0 [7.2] years [range, 22-43 years]) were included in the study. Patients received IV pamidronate for a mean of 6.9 years (median, 7.1 years [range, 3.7-10.9 years]). Pamidronate was associated with a reduction in bone pain and a significant reduction in BALP in all patients at the end of follow-up (P < 0.02). The mean reduction from baseline in CTX-I concentration (measured in 3 patients) was 56%; this difference was not significant. Mean BMD values of FDas were significantly increased at 12 months (by 5.9%; P < 0.05) compared with baseline; but was not significantly increased at 24 months (7.3%), probably reflecting a higher dispersion of values due to individual responses to treatment. No significant changes were observed in CLa BMDs. Mean BMD of FDa had a numerically lower decrease of 15.3% compared with CLa at baseline; these decreases with pamidronate were 10.8% at 12 months (P = NS) and 9.3% at 24 months (P < 0.05). Refilling of osteolytic lesions was not observed. CONCLUSIONS: These patients with FD of bone treated with IV pamidronate long term had improvement in bone pain and BMD. The effectiveness of individualized pamidronate administration in the long-term treatment of FD in adult patients should be investigated in blinded controlled trials.

15.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;40(2): 221-227, Feb. 2007. tab, graf
Artículo en Inglés | LILACS | ID: lil-440490

RESUMEN

We assessed the effect of chronic hyperglycemia on bone mineral density (BMD) and bone remodeling in patients with type 2 diabetes mellitus. We investigated 42 patients with type 2 diabetes under stable control for at least 1 year, 22 of them with good metabolic control (GMC: mean age = 48.8 ± 1.5 years, 11 females) and 20 with poor metabolic control (PMC: mean age = 50.2 ± 1.2 years, 8 females), and 24 normal control individuals (CG: mean age = 46.5 ± 1.1 years, 14 females). We determined BMD in the femoral neck and at the L2-L4 level (DEXA) and serum levels of glucose, total glycated hemoglobin (HbA1), total and ionic calcium, phosphorus, alkaline phosphatase, follicle-stimulating hormone, intact parathyroid hormone (iPTH), 25-hydroxyvitamin D (25-OH-D), insulin-like growth factor I (IGFI), osteocalcin, procollagen type I C propeptide, as well as urinary levels of deoxypyridinoline and creatinine. HbA1 levels were significantly higher in PMC patients (12.5 ± 0.6 vs 7.45 ± 0.2 percent for GMC and 6.3 ± 0.9 percent for CG; P < 0.05). There was no difference in 25-OH-D, iPTH or IGFI levels between the three groups. BMD values at L2-L4 (CG = 1.068 ± 0.02 vs GMC = 1.170 ± 0.03 vs PMC = 1.084 ± 0.02 g/cm²) and in the femoral neck (CG = 0.898 ± 0.03 vs GMC = 0.929 ± 0.03 vs PMC = 0.914 ± 0.03 g/cm²) were similar for all groups. PMC presented significantly lower osteocalcin levels than the other two groups, whereas no significant difference in urinary deoxypyridine was observed between groups. The present results demonstrate that hyperglycemia is not associated with increased bone resorption in type 2 diabetes mellitus and that BMD is not altered in type 2 diabetes mellitus.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Densidad Ósea/fisiología , Remodelación Ósea/fisiología , /sangre , Hiperglucemia/sangre , Absorciometría de Fotón , Biomarcadores/sangre , Estudios de Casos y Controles , /metabolismo , Hiperglucemia/metabolismo
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