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1.
Lab Anim ; 55(1): 30-42, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32460606

RESUMO

Changes in bone mineral content of calcium (Ca), phosphorous (P), magnesium and potassium for male and female Wistar rats during their development from 3 weeks old to adulthood (27 weeks old) were measured. Bone mineral content was related to areal bone mineral density (BMD) which was measured in vivo at the femoral neck using a calibrated X-ray transmission system to obtain basal curves as a function of the age of the specimen. Diagnostic curves were built to determine low BMD (osteopaenia) and osteoporosis in female rats fed a Ca-depleted diet (50%) based on the obtained data and the criteria established by the World Health Organization. Bone mineral content is directly related to sex and age, but P did not change throughout the experimental period. P content did not exhibit significant changes with growing, while Ca was greatest in male rats, producing significant differences in the Ca:P ratio. Male rats reach the Ca:P ratio peak before female rats. However, areal BMD does not follow the same trend. On the other hand, osteoporosis produced a 45% decrease in this parameter for young and mature adults. These results make Z-score values available to diagnose bone-mass losses and hence the possibility of improving the conditions of non-contact measurement of BMD in vivo. This technique can be used for future experiments with Wistar rats.


Assuntos
Densidade Óssea , Fêmur/fisiologia , Osteoporose/fisiopatologia , Ratos/fisiologia , Animais , Modelos Animais de Doenças , Feminino , Masculino , Ratos Wistar
2.
Nutrients ; 12(11)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33114068

RESUMO

Childhood and adolescence are crucial stages of life for bone health. Therefore, an adequate calcium intake and a healthy life style constitute the main strategies to prevent the risk of osteoporosis-related fractures during adulthood. It has been demonstrated that inclusion of indigestible carbohydrates in foods can help improve calcium absorption in growing stages. The objective of this study was to evaluate the effect of supplementation of soluble and insoluble fibers extracted from O. ficus indica cladodes on calcium bioavailability. Male Wistar rats 4-week old were fed diets added with soluble and insoluble fibers extracted from O. ficus indica cladodes at early and late maturity stages, as the only source of calcium. The mineral content, bone mineral density (BMD), physical, microstructural, and biomechanical properties of rat femurs were determined. The bones of rats fed with diets containing a soluble fiber extracted from O. ficus indica at early and late maturity stages exhibited better bone properties (resistance to fracture, microarchitecture, and calcium content) than control rats and rats fed with an insoluble fiber from O. ficusindica cladodes at both maturity stages. As expected, based on these results, the BMD values were higher in adolescent and pubertal rats fed with a diet containing the O. ficus indica soluble fiber. These results demonstrate that the soluble fiber from O. ficus indica cladodes is indeed a valuable source of bioavailable calcium, which contributes to improve physical, densitometric, biomechanical, and microstructural properties of bone in growing rats.


Assuntos
Envelhecimento/efeitos dos fármacos , Cálcio da Dieta/farmacocinética , Fibras na Dieta/farmacologia , Opuntia/química , Extratos Vegetais/farmacocinética , Animais , Disponibilidade Biológica , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Masculino , Ratos , Ratos Wistar
3.
Nutrients ; 12(5)2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32429103

RESUMO

Osteoporosis is a disease of the skeletal system characterized by low bone mass and bone weakening, which increase the risk of fracture. This disease is associated with menopause because hypoestrogenism induces the maturation and activation of osteoclasts. In addition, a low dietary intake of calcium leads to low bone mineral density and postmenopausal osteoporosis. The objectives of this work were to determine calcium bioavailability of Opuntia ficus-indica cladodes at a late maturity stage and to assess its contribution in improving bone health in an ovariectomized rat model. Two-month-old Wistar female rats (n = 35) were used and distributed in seven experimental groups: (i) control group (Crtl), (ii) sham group (SH), (iii) ovariectomized group (OVX), (iv) ovariectomized group supplemented with calcium citrate (CCa), (v) ovariectomized group supplemented with O. ficus-indica powder (NI), (vi) ovariectomized group supplemented with soluble fiber from O. ficus-indica (FS) and (vii) ovariectomized group supplemented with insoluble fiber from O. ficus-indica (FI). Our results showed that calcium in the soluble fiber of O. ficus-indica is bioavailable and contributes to improve the physical, densitometric, biomechanical and microstructural properties of bones in ovariectomized rats. These findings indicated that O. ficus-indica cladodes at a late maturity stage represent a good source of bioavailable calcium and consumption of these cladodes might be beneficial for the prevention of osteoporosis and other bone diseases.


Assuntos
Citrato de Cálcio/farmacocinética , Cálcio da Dieta/farmacocinética , Opuntia/química , Osteoporose Pós-Menopausa/tratamento farmacológico , Extratos Vegetais/farmacocinética , Animais , Disponibilidade Biológica , Osso e Ossos/efeitos dos fármacos , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Humanos , Osteoporose Pós-Menopausa/etiologia , Ovariectomia/efeitos adversos , Ratos , Ratos Wistar
4.
Biol Trace Elem Res ; 197(1): 224-232, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31919787

RESUMO

This study evaluates the effect of three calcium levels in the diet (normal, moderate, and severe calcium depletion) on bone metabolism of male Wistar rats during their growth period. Bone mineral density (BMD) and femur length were determined in vivo during the growth stage using a single X-ray transmission system. The apparent calcium absorption was calculated in the rat adolescent and adulthood stages. At the end of the experiment, calcium concentrations in serum and urine were analyzed. The bones were evaluated postmortem to corroborate in vivo analyses. Microstructural properties of cortical and trabecular tissues of femurs bones were assessed using scanning electron microscopy. Bone mineral contents (Mg, Ca, P, and K) were quantified by inductively coupled plasma. Severe calcium depletion in the diets in the development stage affects the bone quality parameters such as bone mineral density and mineral content. Moreover, it was found thinner cortical and trabecular bone areas. Additionally, it was found that severe calcium depletion increased the apparent absorption of calcium as a defense mechanism, but with the decrease of the BMD peak, and the thickness of cortical bone as well as trabecular bone porosity. The severe calcium depletion increased the efficiency of apparent absorption calcium as a defense mechanism, but, even so, decreases the BMD peak as well as the thickness of cortical bone and trabecular bone porosity.


Assuntos
Cálcio , Magnésio , Animais , Densidade Óssea , Dieta , Fêmur , Masculino , Ratos , Ratos Wistar
5.
Biol Trace Elem Res ; 194(1): 168-176, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31127473

RESUMO

This work determines the effect nopal consumption at different maturity stages (60, 200, 400, and 600 g) as the only calcium source in bone metabolism. The apparent mineral absorption, the biomarkers of bone metabolism, the bone mineral density at different femoral regions, and crystal properties of the bone were evaluated during the growth stage. The Ca absorption was increased with the rat age in most of the experimental groups, while Mg supplementation decreased intestinal absorption probably due to a saturation process. Intestinal Ca and Mg absorption showed an opposite trend; this result suggests that both ions can compete for vitamin D absorption sites. The percentage of absorption of K was lower in the groups fed with Nopal; nevertheless, due to supplementation, the net absorption was higher than the control group. In all groups, osteocalcin levels decreased with the rat age. Nopal consumption increased osteocalcin levels during the adolescence stage in comparison to the control group. Amino N-terminal propeptide of type I procollagen levels increased in puberty and adolescence in all groups compared to the control group. Bone mineral density in different femoral regions was lower in the groups fed with nopal at early maturity stages (N-60 and N-200) than the groups fed with nopal at late maturity stages (N-400 and N-600). The crystal size of hydroxyapatite exhibited changes for all the groups, indicating the inclusion of mono and divalent ions in calcium replacement. On this basis, the nopal at late maturity stage contributed to bone formation.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Cálcio/metabolismo , Minerais/metabolismo , Opuntia/química , Proteínas de Vegetais Comestíveis/farmacologia , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Cálcio/análise , Crescimento/efeitos dos fármacos , Crescimento/fisiologia , Masculino , Minerais/análise , Ratos , Ratos Wistar
6.
Nutr Hosp ; 29(6): 1419-26, 2014 Jun 01.
Artigo em Espanhol | MEDLINE | ID: mdl-24972483

RESUMO

INTRODUCTION: During menopause there is weight gain and a decrease in bone mineral density (BMD) that has been related with periodontal disease (incidence between 5-30%); therefore, it is essential to assess the risk factors related with anthropometry and BMD. OBJECTIVE: To assess the relationship between body mass index (BMI), skeletal composition, waist circumference, tooth loss, fracture risk, BMD of the spine, hip, femur, and mandible in pre and post-menopausal women with periodontitis. SUBJECTS AND METHODOLOGY: We studied 60 women aged 35-60 years, divided in 4 groups (n = 15): CONTROL GROUP: premenopausal women without periodontitis; Experimental group 1: premenopausal women with periodontitis; Experimental group 2: postmenopausal women without periodontitis; and Experimental group 3: postmenopausal women with periodontitis. Periodontitis was diagnosed by means of a computerized digital periodontal probe; BMD of the mandible by means of digital radiograph with X ray conversion, the number of teeth by digital panoramic radiograph. We measured: BMI, skeletal composition, waist circumference, risk fracture by the FRAX questionnaire. RESULTS: The variables with a negative correlation with periodontitis were: weight, BMI, and BMD of the mandible with risk fracture (p < 0.05). The group that showed differences (ANOVA) was EG3: with older age, lower height, lower BMD of the mandible, and lower number of teeth (P < 0.05). CONCLUSION: Periodontitis in the presence of menopause is related with older age, lower height, low BMD of the mandible, and lower mayor number of teeth. Higher fracture risk is associated with low weight and BMI and low BMD of the mandible.


Introducción: Durante la menopausia existe aumento de peso y disminución de densidad mineral ósea (DMO) el cual se ha relacionado con enfermedad periodontal (incidencia entre 5 a 30%), de ahí que sea indispensable evaluar factores de riesgo relacionados con antropometría y DMO. Objetivo: Evaluar la relación entre el índice de masa corporal (IMC), complexión esquelética, circunferencia de cintura, pérdida dentaria, riesgo de fractura, DMO de columna, cadera, fémur y mandíbula en mujeres pre y postmenopáusicas con periodontitis. Sujetos y metodología: Se estudiaron 60 mujeres de 35-60 años, se estudiaron 4 grupos (n = 15): Grupo control: mujeres premenopáuscas sin periodontitis, Grupo experimental 1: mujeres premenopáusicas con periodontitis, Grupo experimental 2: mujeres postmenopáusicas sin periodontitis y Grupo experimental 3: mujeres postmenopáusicas con periodontitis. La periodontitis fue diagnosticada con sonda periodontal digital computarizada, la DMO de mandíbula por radiografía digital con conversión de rayos X, el número de dientes por radiografía panorámica digital. Se obtuvo: el IMC, la complexión esquelética, circunferencia de cintura, riesgo de fractura mediante el cuestionario FRAX. Resultados: Las variables con correlaciones negativas a periodontitis: peso, IMC y DMO mandibular con riesgo de fractura (P < 0,05). El grupo con diferencias (ANOVA) fue el GE3: con mayor edad y con menor: talla, DMO mandibular y número de piezas dentarias (P < 0,05). Conclusión: La periodontitis con presencia de menopausia se relaciona con mayor edad, menor talla, DMO mandibular baja y menor número de piezas dentarias. Con mayor riesgo de fractura en mujeres: con bajo peso e IMC y DMO mandibular.


Assuntos
Densidade Óssea , Fraturas Ósseas/epidemiologia , Estado Nutricional , Osteoporose Pós-Menopausa/metabolismo , Periodontite/complicações , Pós-Menopausa , Perda de Dente/epidemiologia , Adulto , Antropometria , Composição Corporal , Índice de Massa Corporal , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/epidemiologia , Periodontite/epidemiologia , Perda de Dente/etiologia
7.
Rev Sci Instrum ; 82(12): 125105, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22225247

RESUMO

Bones are the support of the body. They are composed of many inorganic compounds and other organic materials that all together can be used to determine the mineral density of the bones. The bone mineral density is a measure index that is widely used as an indicator of the health of the bone. A typical manner to evaluate the quality of the bone is a densitometry study; a dual x-ray absorptiometry system based study that has been widely used to assess the mineral density of some animals' bones. However, despite the success stories of utilizing these systems in many different applications, it is a very expensive method that requires frequent calibration processes to work properly. Moreover, its usage in small species applications (e.g., rodents) has not been quite demonstrated yet. Following this argument, it is suggested that there is a need for an instrument that would perform such a task in a more reliable and economical manner. Therefore, in this paper we explore the possibility to develop a new, affordable, and reliable single x-ray absorptiometry system. The method consists of utilizing a single x-ray source, an x-ray image sensor, and a computer platform that all together, as a whole, will allow us to calculate the mineral density of the bone. Utilizing an x-ray transmission theory modified through a version of the Lambert-Beer law equation, a law that expresses the relationship among the energy absorbed, the thickness, and the absorption coefficient of the sample at the x-rays wavelength to calculate the mineral density of the bone can be advantageous. Having determined the parameter equation that defines the ratio of the pixels in radiographies and the bone mineral density [measured in mass per unit of area (g/cm(2))], we demonstrated the utility of our novel methodology by calculating the mineral density of Wistar rats' femur bones.


Assuntos
Absorciometria de Fóton/instrumentação , Densidade Óssea , Animais , Bovinos , Feminino , Fêmur/diagnóstico por imagem , Fêmur/fisiologia , Radiografia , Ratos , Ratos Wistar , Fatores de Tempo
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