RESUMO
OBJECTIVE: Osteoporosis is affecting the health of postmenopausal women in the world. In case of that, we explored whether FK-506 could ameliorate osteoporosis by inhibiting the activated CaN/NFAT pathway during oxidative stress. METHODS: First, the castrated rat model is constructed through the bilateral ovariectomy. Hologic Discovery (S/N 80347) dual-energy X-ray absorptiometry assessed bone mineral density (BMD) implemented at left femur of rats. Next, hematoxylin-eosin (H&E) staining observed and calculated the changes of bone trabecular, mean trabecular plate separation (Tb.Sp), mean trabecular plate thickness (Tb.Th), and bone volume fraction (BV/TV). Then, CCK-8 assay, TUNEL assay, ALP kit and alizarin red staining detected the viability, apoptosis, alkaline phosphatase (ALP) activity, and capacity of mineralization respectively. At last, commercially available kits detected the levels of ROS and SOD in transfected MC3T3-E1 cells and bone tissues, and Western blot analysis detected proteins related to apoptosis and CaN/NFAT pathway. RESULTS: FK-506 increased the BMD and changes of bone trabecular in female castrated rats. FK-506 inhibited the oxidative stress and apoptosis by suppressing the activated CaN/NFAT pathway. Low dose of FK-506 improved the viability, ALP activity, and mineralization capacity. What's more, it suppressed the apoptosis of H2O2-induced MC3T3-E1 cells, which was deteriorated by the high dose of FK-506. Briefly, low dose of FK-506 inhibited the oxidative stress by suppressing the activated CaN/NFAT pathway, while high dose of that further inhibited the oxidative stress by suppressing the CaN/NFAT pathway. CONCLUSION: FK-506 ameliorates osteoporosis resulted from osteoblastic apoptosis which caused by suppressing the activated CaN/NFAT pathway during oxidative stress.
Assuntos
Imunossupressores/uso terapêutico , Osteoporose/tratamento farmacológico , Tacrolimo/uso terapêutico , Fosfatase Alcalina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Calcineurina/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Feminino , Fêmur/anatomia & histologia , Fêmur/efeitos dos fármacos , Fêmur/metabolismo , Imunossupressores/farmacologia , Camundongos , Fatores de Transcrição NFATC/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoporose/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Tacrolimo/farmacologia , Tíbia/anatomia & histologia , Tíbia/efeitos dos fármacos , Tíbia/metabolismoRESUMO
PURPOSE: Medial tibial stress syndrome (MTSS) represents a common diagnosis in individuals exposed to repetitive high-stress loads affecting the lower limb, e.g., high-performance athletes. However, the diagnostic approach and therapeutic regimens are not well established. METHODS: Nine patients, diagnosed as MTSS, were analyzed by a comprehensive skeletal analysis including laboratory bone turnover parameters, dual-energy X-Ray absorptiometry (DXA), and high-resolution peripheral quantitative computed tomography (HR-pQCT). RESULTS: In 4/9 patients, bilateral pseudofractures were detected in the mid-shaft tibia. These patients had significantly lower levels of 25-hydroxycholecalciferol compared to patients with MTSS but similar levels of bone turnover parameters. Interestingly, the skeletal assessment revealed significantly higher bone mineral density (BMD) Z-scores at the hip (1.3 ± 0.6 vs. - 0.7 ± 0.5, p = 0.013) in patients with pseudofractures and a trend towards higher bone microarchitecture parameters measured by HR-pQCT at the distal tibia. Vitamin D supplementation restored the calcium-homeostasis in all patients. Combined with weight-bearing as tolerated, pseudofractures healed in all patients and return to competition was achieved. CONCLUSION: In conclusion, deficient vitamin D levels may lead to pseudofractures due to localized deterioration of mineralization, representing a pivotal component of MTSS in athletes with increased repetitive mechanical loading of the lower limbs. Moreover, the manifestation of pseudofractures is not a consequence of an altered BMD nor microarchitecture but appears in patients with exercise-induced BMD increase in combination with reduced 25-OH-D levels. The screening of MTSS patients for pseudofractures is crucial for the initiation of an appropriate treatment such as vitamin D supplementation to prevent a prolonged course of healing or recurrence. LEVEL OF EVIDENCE: III.
Assuntos
Traumatismos em Atletas/patologia , Síndrome do Estresse Tibial Medial/patologia , 25-Hidroxivitamina D 2/sangue , Absorciometria de Fóton , Adulto , Traumatismos em Atletas/diagnóstico por imagem , Traumatismos em Atletas/metabolismo , Traumatismos em Atletas/terapia , Densidade Óssea , Remodelação Óssea , Cálcio/metabolismo , Suplementos Nutricionais , Feminino , Humanos , Masculino , Síndrome do Estresse Tibial Medial/diagnóstico por imagem , Síndrome do Estresse Tibial Medial/metabolismo , Síndrome do Estresse Tibial Medial/terapia , Tíbia/anatomia & histologia , Tíbia/diagnóstico por imagem , Tíbia/metabolismo , Tíbia/patologia , Tomografia Computadorizada por Raios X , Vitamina D/administração & dosagem , Suporte de Carga , Adulto JovemRESUMO
Importance: Few studies have assessed the effects of daily vitamin D doses at or above the tolerable upper intake level for 12 months or greater, yet 3% of US adults report vitamin D intakes of at least 4000 IU per day. Objective: To assess the dose-dependent effect of vitamin D supplementation on volumetric bone mineral density (BMD) and strength. Design, Setting, and Participants: Three-year, double-blind, randomized clinical trial conducted in a single center in Calgary, Canada, from August 2013 to December 2017, including 311 community-dwelling healthy adults without osteoporosis, aged 55 to 70 years, with baseline levels of 25-hydroxyvitamin D (25[OH]D) of 30 to 125 nmol/L. Interventions: Daily doses of vitamin D3 for 3 years at 400 IU (n = 109), 4000 IU (n = 100), or 10â¯000 IU (n = 102). Calcium supplementation was provided to participants with dietary intake of less than 1200 mg per day. Main Outcomes and Measures: Co-primary outcomes were total volumetric BMD at radius and tibia, assessed with high resolution peripheral quantitative computed tomography, and bone strength (failure load) at radius and tibia estimated by finite element analysis. Results: Of 311 participants who were randomized (53% men; mean [SD] age, 62.2 [4.2] years), 287 (92%) completed the study. Baseline, 3-month, and 3-year levels of 25(OH)D were 76.3, 76.7, and 77.4 nmol/L for the 400-IU group; 81.3, 115.3, and 132.2 for the 4000-IU group; and 78.4, 188.0, and 144.4 for the 10â¯000-IU group. There were significant group × time interactions for volumetric BMD. At trial end, radial volumetric BMD was lower for the 4000 IU group (-3.9 mg HA/cm3 [95% CI, -6.5 to -1.3]) and 10â¯000 IU group (-7.5 mg HA/cm3 [95% CI, -10.1 to -5.0]) compared with the 400 IU group with mean percent change in volumetric BMD of -1.2% (400 IU group), -2.4% (4000 IU group), and -3.5% (10â¯000 IU group). Tibial volumetric BMD differences from the 400 IU group were -1.8 mg HA/cm3 (95% CI, -3.7 to 0.1) in the 4000 IU group and -4.1 mg HA/cm3 in the 10â¯000 IU group (95% CI, -6.0 to -2.2), with mean percent change values of -0.4% (400 IU), -1.0% (4000 IU), and -1.7% (10â¯000 IU). There were no significant differences for changes in failure load (radius, P = .06; tibia, P = .12). Conclusions and Relevance: Among healthy adults, treatment with vitamin D for 3 years at a dose of 4000 IU per day or 10â¯000 IU per day, compared with 400 IU per day, resulted in statistically significant lower radial BMD; tibial BMD was significantly lower only with the 10â¯000 IU per day dose. There were no significant differences in bone strength at either the radius or tibia. These findings do not support a benefit of high-dose vitamin D supplementation for bone health; further research would be needed to determine whether it is harmful. Trial Registration: ClinicalTrials.gov Identifier: NCT01900860.
Assuntos
Densidade Óssea/efeitos dos fármacos , Colecalciferol/administração & dosagem , Suplementos Nutricionais , Vitaminas/administração & dosagem , Absorciometria de Fóton , Administração Oral , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Análise de Elementos Finitos , Resistência à Flexão , Humanos , Masculino , Pessoa de Meia-Idade , Rádio (Anatomia)/anatomia & histologia , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/anatomia & histologia , Tíbia/diagnóstico por imagem , Falha de Tratamento , Vitamina D/análogos & derivados , Vitamina D/sangueRESUMO
Several lines of bioarchaeological research have confirmed the gradual decline in lower limb loading among past human populations, beginning with the transition to agriculture. The goal of this study was to assess whether human tibial curvature reflects this decline, with a special emphasis on the time-span during which the pace of technological change has been the most rapid. Our study is the first (1) to apply longitudinal curvature analysis in the antero-posterior (A-P) and medio-lateral (M-L) planes to the human tibia, and (2) that incorporates a broad temporal population sample including the periods of intensification of agriculture, urbanization and industrialization (from 2900 BC to the 21st century AD; N = 435) within Czech territories. Using three-dimensional geometric morphometrics, we investigated whether anterior tibial curvature mirrors assumed diminishing lower limb loading between prehistoric and industrialized societies and explored its shape in all three dimensions. Results showed the continuous trend of A-P straightening of the shaft. This straightening was associated with a relative sigmoidal curve accentuation in the M-L plane. Given the timescale involved and the known phenomenon of declining mobility, such adaptive changes in bone geometry can be interpreted in terms of the diminishing biomechanical demands on the tibia under different living conditions.
Assuntos
Fósseis , Tíbia/anatomia & histologia , Feminino , História Antiga , Humanos , MasculinoRESUMO
Exercise has long-lasting benefits to bone mass and structural strength even after cessation. Combining exercise with a calcium- and phosphorus-supplemented diet increases cortical bone mineral content (BMC), area, and yield force more than exercise alone in adult mice. These increases could also be maintained after stopping exercise if the modified diet is maintained. It was hypothesized that combining exercise with a mineral-supplemented diet would lead to greater cortical BMC, area, and yield force immediately after a lengthy exercise program and after an equally long period of non-exercise (detraining) in adult mice. Male, 16-week old C57Bl/6 mice were assigned to 9 weight-matched groups-a baseline group, exercise and non-exercise groups fed a control or mineral-supplemented diet for 8 weeks, exercise + detraining and non-exercise groups fed a control or mineral-supplemented diet for 16 weeks. Exercise + detraining consisted of 8 weeks of exercise followed by 8 weeks without exercise. The daily exercise program consisted of running on a treadmill at 12 m/min, 30 min/day. After 8 weeks, mice fed the supplemented diet had greater tibial cortical BMC and area, trabecular bone volume/tissue volume (BV/TV), bone mineral density (vBMD), yield force, and ultimate force than mice fed the control diet. Exercise increased cortical BMC and area only when coupled with the supplemented diet. After 16 weeks, both exercised and non-exercised mice fed the supplemented diet maintained greater tibial cortical BMC and area, trabecular BV/TV, vBMD, yield force, and ultimate force than mice fed the control diet. Combining exercise with a mineral-supplemented diet leads to greater bone mass and structural strength than exercise alone. These benefits remain after an equally long period of detraining. Long-term use of dietary mineral supplements may help increase and maintain bone mass with aging in adult mice.
Assuntos
Densidade Óssea , Suplementos Nutricionais , Corrida/fisiologia , Tíbia/anatomia & histologia , Tíbia/fisiologia , Animais , Fenômenos Biomecânicos , Peso Corporal , Masculino , Camundongos Endogâmicos C57BL , Tamanho do Órgão , Distribuição Aleatória , Tíbia/diagnóstico por imagemRESUMO
Transverse lines, called Harris Lines (HL), osteological markers of recovery from growth arrest episodes, are visible in radiograms of recent and Pleistocene fossil bones. Since on the one hand they mark stressful episodes in life, and on the other are mainly used to trace health fluctuations in prehistoric human communities, I used a cave bear population to check if the processes that could affect the specie' condition were in any way reflected in the bone structure. 392 bear bones from Bear Cave in Kletno (collection: Department of Palaeozoology, University of Wroclaw), dated as 32 100 ±1300 to >49 000 years BP, were radiologically examined. The bones were found in a non-anatomical position; morphological analysis indicated that they belonged to different individuals. HL shadows were observed on 9 tibiae and 3 radii: 8.8% out of the 59 tibiae and 77 radii and 3.1% of all the bones. At least 3 transverse lines were recognised in those cases; the specimens were histologically examined. The bear individuals in question experienced regular malnutrition periods during their ontogeny. Starvation resulting in growth inhibition involved young individuals, aged 1 to 4 years. Juveniles aged 6 months, i.e. before weaning, or younger, showed no signs of nutritional stress. Starvation periods associated with seasonal food deficit were not long or common and had no significant effect on the development and welfare of the species. This is the first description of the occurrence of transverse lines in the Pleistocene bear.
Assuntos
Desenvolvimento Ósseo/fisiologia , Osso e Ossos/anatomia & histologia , Meio Ambiente , Fósseis/anatomia & histologia , Ursidae/anatomia & histologia , Ursidae/crescimento & desenvolvimento , Animais , Osso e Ossos/patologia , Osso e Ossos/ultraestrutura , Fósseis/patologia , Fósseis/ultraestrutura , História Antiga , Paleontologia , Polônia , Tíbia/anatomia & histologia , Tíbia/crescimento & desenvolvimento , Tíbia/patologiaRESUMO
High-latitude (i.e., "polar") Mesozoic fauna endured months of twilight and relatively low mean annual temperatures. Yet non-avian dinosaurs flourished in this taxing environment. Fossils of basal ornithopod dinosaurs ("hypsilophodontids") are common in the Early Cretaceous high-latitude sediments of Victoria, Australia, and four taxa have been described; although their ontogenetic histories are largely unexplored. In the present study, eighteen tibiae and femora were utilized in the first multi-specimen ontogenetic histological analysis of Australian polar hypsilophodontids. The sample consists of eleven individuals from the Flat Rocks locality (Late Valanginian or Barremian), and five from the Dinosaur Cove locality (Albian). In both groups, growth was most rapid during the first three years, and skeletal maturity occurred between five and seven years. There is a weak asymptotic trend in a plot of growth mark count versus femur length, with considerable individual variation. Histology suggests two genera are present within the Dinosaur Cove sample, but bone microstructure alone could not distinguish genera within the Flat Rocks sample, or across the two geologically separate (~ 26 Ma) localities. Additional histologic sampling, combined with morphological analyses, may facilitate further differentiation between ontogenetic, individual, and species variation.
Assuntos
Dinossauros/anatomia & histologia , Fêmur/ultraestrutura , Fósseis/história , Tíbia/ultraestrutura , Animais , Clima Frio , Dinossauros/classificação , Dinossauros/fisiologia , Extinção Biológica , Fêmur/anatomia & histologia , Fêmur/fisiologia , História Antiga , Microscopia , Osteogênese/fisiologia , Filogenia , Tíbia/anatomia & histologia , Tíbia/fisiologia , VitóriaRESUMO
ABSTRACT: The Canary Archipelago was colonized by North African Berbers who arrived at the Islands in the first millenium BC. Although it was classically considered that the prehispanic population was more or less uniform, recent genetic analysis has disclosed that some differences did exist between inhabitants of the different islands. From pure anthropometrical point of view, detailed inspection of some bones such as tibiae of prehispanic inhabitants of different islands allow the detection of some differences in tibial shape, especially regarding the relative size of both the proximal and distal thirds of these bones. On this basis, we have elaborated and calculated several indexes combining distal and proximal breadth measurements that define the global shape of the tibia. We have compared these indexes among the prehispanic population of the three islands for which sex has been accurately established. Both men and women from La Gomera, and, especially, from El Hierro, showed thicker distal ends of the tibiae with respect to proximal ones, in contrast with the population of Gran Canaria. In addition, differences among male and female tibiae were more marked among the population of Gran Canaria than among those of Gomera and El Hierro. Differences in these indexes could point either to differences in genetical background or to differences in activity. Compared with single anthropometric measurements, these indices separate better the population of the different islands. Just the opposite was observed when logistic regression analysis was used to analyse differences in sex.
Assuntos
Tíbia/anatomia & histologia , População Branca/estatística & dados numéricos , Antropologia Física , Feminino , História Antiga , Humanos , Masculino , EspanhaRESUMO
Hesperidin (HSP) and naringin (NAR), flavanones rich in citrus fruits, support skeletal integrity in adult and aging rodent models. This study determined whether maternal consumption of HSP and NAR favorably programs bone development, resulting in higher bone mineral density (BMD) and greater structure and biomechanical strength (i.e., peak load) in female offspring. Female CD-1 mice were fed a control diet or a HSP + NAR diet five weeks before pregnancy and throughout pregnancy and lactation. At weaning, female offspring were fed a control diet until six months of age. The structure and BMD of the proximal tibia were measured longitudinally using in vivo microcomputed tomography at 2, 4, and 6 months of age. The trabecular bone structure at two and four months and the trabecular BMD at four months were compromised at the proximal tibia in mice exposed to HSP and NAR compared to the control diet (p < 0.001). At six months of age, these differences in trabecular structure and BMD at the proximal tibia had disappeared. At 6 months of age, the tibia midpoint peak load, BMD, structure, and the peak load of lumbar vertebrae and femurs were similar (p > 0.05) between the HSP + NAR and control groups. In conclusion, maternal consumption of HSP and NAR does not enhance bone development in female CD-1 offspring.
Assuntos
Desenvolvimento Ósseo/efeitos dos fármacos , Flavanonas/farmacologia , Hesperidina/farmacologia , Tíbia/efeitos dos fármacos , Animais , Citrus/química , Feminino , Fêmur/anatomia & histologia , Fêmur/efeitos dos fármacos , Vértebras Lombares/anatomia & histologia , Vértebras Lombares/efeitos dos fármacos , Camundongos , Extratos Vegetais/farmacologia , Tíbia/anatomia & histologia , Microtomografia por Raio-XRESUMO
OBJECTIVE: The Jomon, one of the ancestral populations of modern Japanese, were hunter-gatherers inhabiting the Japanese archipelago from 11,000 to 300 BC. We evaluated changes in the diaphyseal morphology of the fibula from the middle to the final phase of the Jomon period, compared to the morphology of other historical and modern populations from the Japanese archipelago, to elucidate temporal changes in habitual activities and possible division of labor among males and females. MATERIAL AND METHOD: Jomon specimens of 107 males and 97 females were obtained from the shell mounds of the Pacific coastal area of East Japan, distinguishing between middle (3,000-2,000 BC) and late-final (2,000-300 BC) phases of the Jomon period. Mid-shaft morphology of the fibula and tibia were compared to morphological measurements of specimens from Yayoi (37 males, 28 females), medieval (56 males, 56 females), early modern (51 males, 50 females), and modern (125 males, 68 females) periods. RESULT: Largest values of fibular areas and relative fibular-to-tibial areas were identified in males from the late-final Jomon phase, compared to the middle Jomon phase and after the Yayoi period. These period-specific differences in fibular area were smaller in females, with the largest between-sex difference identified in the late-final Jomon phase. DISCUSSION: Results confirm a change in the habitual activity pattern of males in the late-final phase. Males of the late-final Jomon phase likely did more long-distance traveling to the inland/mountainous region, as part of an ecological change that occurred during the middle to the late-final Jomon phase. Am J Phys Anthropol 160:708-718, 2016. © 2016 Wiley Periodicals, Inc.
Assuntos
Antropologia Física , Fíbula/anatomia & histologia , Atividades Humanas/história , Feminino , História do Século XXI , História Antiga , História Medieval , Humanos , Japão , Masculino , Oceano Pacífico , Fatores Sexuais , Estatísticas não Paramétricas , Tíbia/anatomia & histologiaRESUMO
Long bones respond to mechanical loading through functional adaptation in a suite of morphological characteristics that together ensure structural competence to in vivo loading. As such, adult bone structure is often used to make inferences about past behavior from archaeological remains. However, such biomechanical approaches often investigate change in just one aspect of morphology, typically cross-sectional morphology or trabecular structure. The relationship between longitudinal bone curvature and mobility patterns is less well understood, particularly in the tibia, and it is unknown how tibial curvature and diaphyseal cross-sectional geometry interact to meet the structural requirements of loading. This study examines tibial curvature and its relationship with diaphyseal cross-sectional geometry (CSG) and body size in preindustrial Central Europeans spanning â¼6150 years following the introduction of agriculture in the region. Anteroposterior centroid displacement from the proximo-distal longitudinal axis was quantified at nine diaphyseal section locations (collectively representative of diaphyseal curvature) in 216 tibial three-dimensional laser scans. Results documented significant and corresponding temporal declines in midshaft centroid displacement and CSG properties. Significant correlations were found between mid-diaphyseal centroid displacement and all mobility-related CSG properties, while the relationship weakened toward the diaphyseal ends. No significant relationship was found between centroid displacement and body size variables with the exception of the most distal section location. Results support a relationship between tibial curvature and cross-sectional geometry among prehistoric Central European agricultural populations, and suggest that changes in mechanical loading may have influenced a suite of morphological features related to bone adaptation in the lower limb.
Assuntos
Agricultura/história , Tíbia/anatomia & histologia , Tíbia/fisiologia , Adulto , Antropologia Física , Antropometria , Fenômenos Biomecânicos/fisiologia , Europa (Continente) , Feminino , História Antiga , Humanos , MasculinoRESUMO
In this study we investigated the effect of supplementing the diet of the growing male rat with different levels of calcium (from low to higher than recommended intakes at constant Ca/P ratio), on multiple factors (bone mass, strength, size, geometry, material properties, turnover) influencing bone strength during the bone accrual period. Rats, age 28days were supplemented for 4weeks with high Ca (1.2%), adequate Ca (0.5%) or low Ca level (0.2%). Bone metabolism and structural parameters were measured. No changes in body weight or food intake were observed among the groups. As anticipated, compared to the adequate Ca intake, low-Ca intake had a detrimental impact on bone growth (33.63 vs. 33.68mm), bone strength (-19.7% for failure load), bone architecture (-58% for BV/TV) and peak bone mass accrual (-29% for BMD) due to the hormonal disruption implied in Ca metabolism. In contrast, novel, surprising results were observed in that higher than adequate Ca intake resulted in improved peak bone strength (106 vs. 184N/mm for the stiffness and 61 vs. 89N for the failure load) and bone material properties (467 vs. 514mPa for tissue hardness) but these effects were not accompanied by changes in bone mass, size, microarchitecture or bone turnover. Hormonal factors, IGF-I and bone modeling were also evaluated. Compared to the adequate level of Ca, IGF-I level was significantly lower in the low-Ca intake group and significantly higher in the high-Ca intake group. No detrimental effects of high Ca were observed on bone modeling (assessed by histomorphometry and bone markers), at least in this short-term intervention. In conclusion, the decrease in failure load in the low calcium group can be explained by the change in bone geometry and bone mass parameters. Thus, improvements in mechanical properties can be explained by the improved quality of intrinsic bone tissue as shown by nanoindentation. These results suggest that supplemental Ca may be beneficial for the attainment of peak bone strength and that multiple factors linked to bone mass and strength should be taken into account when setting dietary levels of adequate mineral intake to support optimal peak bone mass acquisition.
Assuntos
Osso e Ossos/fisiologia , Cálcio da Dieta/farmacologia , Crescimento e Desenvolvimento/efeitos dos fármacos , Absorciometria de Fóton , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/anatomia & histologia , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Cálcio/metabolismo , Fêmur/anatomia & histologia , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Fêmur/fisiologia , Imageamento Tridimensional , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos Sprague-Dawley , Tíbia/anatomia & histologia , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Tíbia/fisiologia , Suporte de Carga , Microtomografia por Raio-XRESUMO
Diets rich in omega-3s have been thought to prevent both obesity and osteoporosis. However, conflicting findings are reported, probably as a result of gene by nutritional interactions. Peroxisome proliferator-activated receptor-gamma (PPARγ) is a nuclear receptor that improves insulin sensitivity but causes weight gain and bone loss. Fish oil is a natural agonist for PPARγ and thus may exert its actions through the PPARγ pathway. We examined the role of PPARγ in body composition changes induced by a fish or safflower oil diet using two strains of C57BL/6J (B6); i.e. B6.C3H-6T (6T) congenic mice created by backcrossing a small locus on Chr 6 from C3H carrying 'gain of function' polymorphisms in the Pparγ gene onto a B6 background, and C57BL/6J mice. After 9months of feeding both diets to female mice, body weight, percent fat and leptin levels were less in mice fed the fish oil vs those fed safflower oil, independent of genotype. At the skeletal level, fish oil preserved vertebral bone mineral density (BMD) and microstructure in B6 but not in 6T mice. Moreover, fish oil consumption was associated with an increase in bone marrow adiposity and a decrease in BMD, cortical thickness, ultimate force and plastic energy in femur of the 6T but not the B6 mice. These effects paralleled an increase in adipogenic inflammatory and resorption markers in 6T but not B6. Thus, compared to safflower oil, fish oil (high ratio omega-3/-6) prevents weight gain, bone loss, and changes in trabecular microarchitecture in the spine with age. These beneficial effects are absent in mice with polymorphisms in the Pparγ gene (6T), supporting the tenet that the actions of n-3 fatty acids on bone microstructure are likely to be genotype dependent. Thus caution must be used in interpreting dietary intervention trials with skeletal endpoints in mice and in humans.
Assuntos
Osso e Ossos/metabolismo , Dieta , Ácidos Graxos Ômega-3/farmacologia , Ácidos Graxos Ômega-6/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Tecido Adiposo Marrom/anatomia & histologia , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/anatomia & histologia , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Adiposidade/efeitos dos fármacos , Adiposidade/fisiologia , Animais , Biomarcadores/metabolismo , Fenômenos Biomecânicos/efeitos dos fármacos , Composição Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Medula Óssea/fisiologia , Osso e Ossos/efeitos dos fármacos , Contagem de Células , Suplementos Nutricionais , Feminino , Fêmur/anatomia & histologia , Fêmur/efeitos dos fármacos , Fêmur/fisiologia , Óleos de Peixe/farmacologia , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Coluna Vertebral/anatomia & histologia , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/fisiologia , Tíbia/anatomia & histologia , Tíbia/efeitos dos fármacos , Tíbia/fisiologiaRESUMO
1. Ipriflavone (IP) has been widely studied in humans and is effective for inhibiting osteoclastic bone resorption and enhancing osteoblastic bone formation. The aim of this study was to investigate the effects of IP on the structural histology and histomorphometric parameters of tibia in laying hens fed on a low-calcium diet. 2. A total of 200 Hy-Line Brown laying hens, 24 weeks of age, were divided randomly into 4 groups which were fed on one of 4 diets (CaN, standard diet; CaL, low-calcium diet; IP1, low-calcium diet + 8 mg/kg of IP; IP2, low-calcium diet + 20 mg/kg of IP) for 60 d after which 10 hens of each group, chosen at random, were killed and the tibiae were processed and assessed under a fluorescent microscope 3. The cortical bone showing resorption cavities had become porous, and medullary bone did not completely fill the marrow cavity in the CaL group compared with the CaN group. However, in the IP2 group, the cortical bone showed a structure comparable to the CaN group with an absence of resorption cavities, and more medullary bone filled the marrow cavity compared with the CaL group. 4. The CaL hens had significantly lower trabecular bone area, trabecular perimeter, per cent trabecular area, trabecular number and trabecular thickness and significantly wider trabecular separation compared with CaN. These results indicated that the low-calcium diet led to increased loss of tibial bone, eventually causing osteoporosis. However, compared with the CaL group, the IP2 group caused a significant increase in trabecular bone area and bone quality. 5. It is concluded that even in hens fed on a low-calcium diet, the addition of 20 mg/kg IP exerted beneficial effects on histological structure and structural histomorphometric parameters of tibia, indicating an alleviation of caged layer osteoporosis (CLO).
Assuntos
Cálcio/deficiência , Galinhas/anatomia & histologia , Isoflavonas/farmacologia , Tíbia/anatomia & histologia , Ração Animal/análise , Animais , Galinhas/fisiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Distribuição Aleatória , Reprodução/efeitos dos fármacosRESUMO
Resveratrol has gained popularity as an "anti-aging" compound due to its antioxidant and anti-inflammatory properties. Few studies have investigated the role of resveratrol supplementation in the prevention of age-related bone loss and skeletal disuse despite increased inactivity and age-related bone loss in the elderly. The objective of the study was to investigate the effect of resveratrol supplementation on disuse and age-related bone loss. Old (age 33 months) Fischer 344 × Brown Norway male rats were provided either trans-resveratrol (12.5 mg/kg bw/day) or deionized distilled water by oral gavage for 21 days. Rats were hindlimb-suspended (HLS) or kept ambulatory (AMB) for 14 days. Both femora and tibiae were collected. Bone mass was measured by dual-energy X-ray absorptiometry and bone microstructure was determined by micro-computed tomography. HLS of old male rats accelerated loss of bone mineral content, decreased trabecular bone volume per unit of total volume, and increased trabecular separation. Resveratrol supplementation ameliorated bone demineralization and loss of bone microarchitecture in HLS old male rats. The peak force measured by the three-point bending test was reduced (P = 0.007) in HLS/control compared to AMB/control rats. Resveratrol supplementation ameliorated HLS-induced loss of femur strength. Plasma osteocalcin and alkaline phosphatase was higher (P < 0.04) and C-reactive protein was lower (P = 0.04) in old male rats given resveratrol. The bone protective effects of resveratrol appeared to be mediated through increased osteoblast bone formation, possibly due to reduced inflammation. Based on the results, resveratrol supplementation appeared to provide a feasible dietary therapy for preserving the skeletal system during disuse and age-related bone loss.
Assuntos
Envelhecimento/fisiologia , Osso e Ossos/anatomia & histologia , Osso e Ossos/fisiologia , Suplementos Nutricionais , Elevação dos Membros Posteriores/fisiologia , Estilbenos/administração & dosagem , Estilbenos/farmacologia , Envelhecimento/efeitos dos fármacos , Animais , Biomarcadores/sangue , Fenômenos Biomecânicos/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Proteína C-Reativa/metabolismo , Feminino , Fêmur/anatomia & histologia , Fêmur/efeitos dos fármacos , Fêmur/fisiologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Osteocalcina/sangue , Ratos , Resveratrol , Tíbia/anatomia & histologia , Tíbia/efeitos dos fármacos , Tíbia/fisiologia , CaminhadaRESUMO
1. In a 42-d feeding trial, 264 one-d-old, as hatched, Cobb 400 broiler chickens (6 pens per group, n = 11 per pen in a 2 × 2 factorial arrangement) were fed on two concentrations of dietary calcium (Ca) (9.0 and 7.5 g/kg in starter, 7.5 and 6 g/kg in grower phases) and supplemental phytase (0 and 500 U/kg diet). 2. During d 0-21, the high Ca + phytase diet improved body weight. During d 0-42, feed intake was increased by the low Ca diet and decreased by phytase supplementation. Feed conversion ratio during d 0-21 was improved by the high Ca + phytase diet. 3. At d 42, Ca in duodenal digesta was reduced by low dietary Ca and supplemental phytase. High dietary Ca reduced P in duodenal and jejunal digesta. Phytase reduced digesta P and increased serum P concentration. 4. Relative tibia length decreased with low dietary Ca and increased with phytase. The robusticity index of tibia was improved by the low Ca diet and phytase supplementation. Phytase supplementation increased tibia ash and concentrations of Ca, magnesium (Mg), manganese (Mn), copper (Cu), zinc (Zn) and iron (Fe) in tibia. The low Ca diet increased Mg, Mn and Fe and reduced Cu and Zn in tibia. 5. It was concluded that 7.5 g Ca/kg during weeks 0-3 and 6 g Ca/kg during weeks 3-6 sustained broiler performance and bone ash, while phytase supplementation facilitated tibia mineralisation, particularly during the grower phase.
Assuntos
6-Fitase/administração & dosagem , Calcificação Fisiológica , Cálcio da Dieta/metabolismo , Galinhas/fisiologia , Tíbia/fisiologia , Ração Animal/análise , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cálcio da Dieta/sangue , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Feminino , Conteúdo Gastrointestinal/química , Intestino Delgado/química , Masculino , Minerais/metabolismo , Distribuição Aleatória , Espectrofotometria Atômica/veterinária , Tíbia/anatomia & histologia , Aumento de Peso/efeitos dos fármacosRESUMO
The objective of this study was to examine the effect of embryonic nutritional enrichment on the development and properties of broiler leg bones (tibia and femur) from the prenatal period until maturity. To accomplish the objective, 300 eggs were divided into 2 groups: a noninjected group (control) and a group injected in ovo with a solution containing minerals, vitamins, and carbohydrates (enriched). Tibia and femur from both legs were harvested from chicks on embryonic days 19 (E19) and 21 (E21) and d 3, 7, 14, 28, and 54 posthatch (n = 8). The bones were mechanically tested (stiffness, maximal load, and work to fracture) and scanned in a micro-computed tomography (µCT) scanner to examine the structural properties of the cortical [cortical area, medullary area, cortical thickness, and maximal moment of inertia (Imax)] and trabecular (bone volume percent, trabecular thickness, and trabecular number) areas. To examine bone mineralization, bone mineral density (BMD) of the cortical area was obtained from the µCT scans, and bones were analyzed for the ash and mineral content. The results showed improved mechanical properties of the enriched group between E19 and d 3 and on d 14 (P < 0.05). Differences in cortical morphology were noted between E19 and d 14 as the enriched group had greater medullary area on E19 (femur), reduced medullary area on E21 (both bones), greater femoral cortical area on d 3, and greater Imax of both bones on d 14 (P < 0.05). The major differences in bone trabecular architecture were that the enriched group had greater bone volume percent and trabecular thickness in the tibia on d 7 and the femur on d 28 (P < 0.05). The pattern of mineralization between E19 and d 54 showed improved mineralization in the enriched group on E19 whereas on d 3 and 7, the control group showed a mineralization advantage, and on d 28 and 54, the enriched group showed again greater mineralization (P < 0.05). In summary, this study demonstrated that in ovo enrichment affects multiple bone properties pre- and postnatally and showed that avian embryos are a good model for studying the effect of embryonic nutrition on natal and postnatal development. Most importantly, the enrichment led to improved mechanical properties until d 14 (roughly third of the lifespan of the bird), a big advantage for the young broiler. Additionally, the improved mineralization and trabecular architecture on d 28 and 54 indicate a potential long-term effect of altering embryonic nutrition.
Assuntos
Galinhas/fisiologia , Carboidratos da Dieta/administração & dosagem , Fêmur/crescimento & desenvolvimento , Minerais/administração & dosagem , Tíbia/crescimento & desenvolvimento , Vitaminas/administração & dosagem , Envelhecimento , Animais , Fenômenos Biomecânicos , Densidade Óssea , Calcificação Fisiológica , Embrião de Galinha/anatomia & histologia , Embrião de Galinha/fisiologia , Galinhas/anatomia & histologia , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais/análise , Fêmur/anatomia & histologia , Fêmur/fisiologia , Tíbia/anatomia & histologia , Tíbia/fisiologia , Tomografia Computadorizada por Raios X/veterináriaRESUMO
OBJECTIVE: To evaluate the effects of Prunus domestica L. extracts on fetuses and neonatal skeletal systems. MATERIALS AND METHODS: A total of 32 pregnant mice (Mus musculus) received vehicle and plum hydroalcoholic extract at gestational days 1-18 and during the entire gestational period as well as 10 days postpartum, respectively. A total of 30 nonpregnant mice were fed plum hydroalcoholic extract and plum juice extract for 30 days. Bone calcium content and serum concentrations of calcium, magnesium and alkaline phosphatase were measured. The skeletal systems of their fetuses and neonates were stained with Alcian blue and alizarin red S and the length of femur, tibia, and their ossification center were measured. RESULTS: Crown-rump length of the newborn mice from mothers treated with plum extract (4.61 ± 0.25 mm) was higher compared to the control group (4.48 ± 0.31 mm, p = 0.001), and the femur osteogenesis index of newborn mice from mothers treated with plum extract was also higher (0.87 ± 0.09) compared to the control group (0.81 ± 0.06, p = 0.007). CONCLUSION: The findings showed that pregnant mice treated with plum extract had fetuses and newborn mice with higher osteogenesis index than those of the controls.
Assuntos
Extratos Vegetais/farmacologia , Prunus , Fosfatase Alcalina/sangue , Animais , Animais Recém-Nascidos , Glicemia/análise , Cálcio/análise , Colesterol/sangue , Estatura Cabeça-Cóccix , Feminino , Fêmur/anatomia & histologia , Fêmur/química , Feto , Lipoproteínas HDL , Lipoproteínas LDL/sangue , Magnésio/sangue , Camundongos , Osteogênese , Fósforo/sangue , Gravidez , Coloração e Rotulagem , Tíbia/anatomia & histologia , Tíbia/química , Triglicerídeos/sangueRESUMO
An experiment was performed to determine whether boron had a beneficial effect on bone strength and composition in rabbits with apparent adiposity induced by a high energy diet. Sixty female New Zealand rabbits, aged 8 months, were randomly divided into five groups with the following treatments for seven months: control 1, fed alfalfa hay only (5.91 MJ/kg); control 2, high energy diet (11.76 MJ and 3.88 mg boron/kg); B10, high energy diet+10 mg/kg body weight boron gavage/96 h; B30, high energy diet+30 mg/kg body weight boron gavage/96 h; B50, high energy diet+50mg/kg body weight boron gavage/96 h. Bone boron concentrations were lowest in rabbits fed the high energy diet without boron supplementation, which suggested an inferior boron status. Femur maximum breaking force was highest in the B50 rabbits. Tibia compression strength was highest in B30 and B50 rabbits. All boron treatments significantly increased calcium and magnesium concentrations, and the B30 and B50 treatments increased the phosphorus concentration in tibia of rabbits fed the high energy diet. The B30 treatment significantly increased calcium, phosphorus and magnesium concentrations in femur of rabbits fed the high energy diet. Principal component analysis of the tibia minerals showed that the three boron treatments formed a separate cluster from controls. Discriminant analysis suggested that the concentrations of the minerals in femur could predict boron treatment. The findings indicate boron has beneficial effects on bone strength and mineral composition in rabbits fed a high energy diet.
Assuntos
Osso e Ossos/metabolismo , Boro/farmacologia , Dieta , Ingestão de Energia/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Minerais/metabolismo , Animais , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/anatomia & histologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/fisiologia , Feminino , Fêmur/anatomia & histologia , Fêmur/efeitos dos fármacos , Fêmur/fisiologia , Análise de Componente Principal , Coelhos , Tíbia/anatomia & histologia , Tíbia/efeitos dos fármacos , Tíbia/fisiologiaRESUMO
Yacon flour has been considered a food with prebiotic potential because of the high levels of fructooligosaccharides, which allows for its use in formulating synbiotic foods. The purpose of this study was to evaluate the effect of yacon flour and probiotic (Bifidobacterium longum) on the modulation of variables related to bone health. Thirty-two Wistar rats were divided into 4 groups: control, yacon flour, diet+B. longum, and yacon flour+B. longum. After euthanasia, the bones were removed for analysis of biomechanical properties (thickness, length, and strength of fracture) and mineral content (Ca, Mg, and P); the cecum was removed for analysis of the microbiota and short-chain fatty acids. Tibia Ca, P, and Mg content was significantly (P<.05) higher in groups fed diet+B. longum, yacon flour+B. longum than in the control group. An increase in fracture strength was observed in the yacon flour (8.1%), diet+B. longum (8.6%), and yacon flour+B. longum (14.6%) in comparison to the control group. Total anaerobe and weight of the cecum were higher (P<.05) in rats consuming the yacon flour diet compared with the other groups. Cecal concentration of propionate was higher in all experimental groups compared with the control (P<.05). Yacon flour in combination with B. longum helped increase the concentration of minerals in bones, an important factor in the prevention of diseases such as osteoporosis.