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Sunflower oil is one of the most commonly used fat sources in Argentina, and deep-fat frying is the popular food preparation process. The liver response of feeding a diet containing fried sunflower oil (SFOx) on growing rats was studied. Thirty-nine male weanling Wistar rats were randomly assigned to one of three diets for 8 wks: control (C), sunflower oil (SFO), and a diet containing SFOx, both of the sunflower diets were mixed with a commercial rat chow at weight ratio of 13% (w/w). Body weight and food consumption were recorded weekly. At t=8 wk, lipid profile and glycemia were measured. Visceral adiposity was registered. Liver was weighed and preserved for histological analysis, relative fatty acid profile, fibrosis markers and oxidative status. The three diets did not alter body weights; however, the SFOx fed rats showed increased energy intake and visceral fat; therefore, in liver saturated fat content, trans fatty acids, plus other unidentified minor components, such as hydroperoxides, hydroxides, epidioxides, hydroperoxy epidioxides, hydroxylepidioxides, and epoxides, were detected. The hepatosomatic index of SFOx rats was altered and showed hepatic steatosis. SFOx rats exhibited increased liver dichlorodihydrofluorescein-diacetate and thiobarbituric acid substance levels and oxidized-proteins content. Their livers had lower relative levels of monounsaturated, polyunsaturated fatty acids and catalase activity, but matrix metalloproteinase-9 activity was unchanged. Consumption of a diet rich in fried oil during growth could induce liver damage due to steatosis, excessive lipid toxicity and the accumulation of reactive oxygen species. Further progression could lead to hepatic fibrosis.
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Oral feeding is critical for survival in both humans and animals. However, few studies have reported quantitative behavioral measures associated with the development of oral feeding behaviors. Therefore, the present study investigated developmental changes in the oral feeding behaviors of rats by quantitatively assessing pasta eating and licking behaviors. In the pasta eating test, the time to finish pasta sticks of three different thicknesses (Φ = 0.9, 1.4, and 1.9 mm, 4 cm long) was recorded between postnatal day 29 (P29) and P49, because all rats were able to finish eating these pasta sticks on P29. A developmental decrease in the time to finish pasta sticks of all thicknesses was observed during the initial period of recordings and plateaued before P35. The extent of this decrease was dependent on the thickness of pasta sticks. In the licking test, the number of licks per 10 s and the total intake volume during the test were recorded between P19 and P49, because all rats were able to access and lick the solution on P19. The time courses of developmental increases in the number of licks and the total intake volume were similar to the results obtained in the pasta eating test. Collectively, these results suggest that developmental changes in pasta eating and licking behaviors markedly differed between the weanling and periadolescent periods. The present study also demonstrated the applicability of the pasta eating and licking tests to the quantification of developmental changes in the oral feeding behaviors of rats.
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Ingestión de Alimentos , Conducta Alimentaria , Humanos , Ratas , Animales , Ratas Sprague-DawleyRESUMEN
[Introduction] This study compared the effects of joint immobilization and concurrent electroacupuncture stimulation on fracture line appearance, which is indicative of differences in cortical bone structure, in the femurs of young adult rats. [Materials and Methods] Forty-two 7-week-old Wistar rats were divided into three groups: a hindlimb immobilized group (IM), a hindlimb immobilized group with concurrent electroacupuncture stimulation (IMEA), and an untreated control group (CO). IM and IMEA were immobilized for two weeks with a jacket-type immobilization device that immobilized the hip joint in extension and restricted hip joint adduction and abduction. Acupuncture needles were inserted into the femoral region during the immobilization period in the IMEA group, and continuous alternating current was used for stimulation. A low-frequency stimulator was used to generate electrical current (250 μsec, 50 Hz, 0.24 mA, 500 Ω load resistance), and stimulation was performed daily for two weeks at 10 min/day. The extracted femur was fractured from the anterior part of the diaphysis or metaphyseal end by three-point-bending under constant conditions with 10 mm between the fulcrum and a crosshead speed of 10 mm/min. [Results] IM showed significantly lower Stiffness, Deformation, and Strength values than CO. Bone morphometry parameters also showed lower values for IM. A cement line was observed between lamellar and non-lamellar bone in CO and IMEA, but was indistinct in IM. In CO and IMEA, minute bone fragments were formed in the deep diaphysis region sandwiched between the inner and outer circumferential lamellae, but no such fragments were found in IM. IMEA had less resorption than IM, and lamellar bone with a structure similar to CO was maintained. Moreover, cracks observed in CO and IMEA ran longitudinally in the vicinity of the cement line and rest line, but no such cracks were found in IM. [Discussion and Conclusion] These findings suggest that electroacupuncture mitigates bone weakening in immobilized rat femurs, and this affects the appearance of the fracture line.
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This study aimed to examine the continuous effects of whole body vibration (WBV) on bone properties, in growing rats. Fifty 5-week-old male rats were divided into control and experimental groups. Each experimental group underwent WBV at 50 Hz (0.5 g, 15 min/day, 5 days/week) for 5 or 10 weeks. Bone size, muscle weight and bone mechanical strength of the right tibia were measured. Trabecular bone microstructure, cortical bone geometry and bone mass of the left tibia were analyzed by micro-CT. Serum levels of bone formation/resorption markers were also measured. In rats that underwent 5-week WBV, tibial cortical bone mineral content and cortical bone area significantly increased (p < 0.05), and tibial cortical bone volume, thickness, maximum load, break point and stiffness tended to be increased (p = 0.05-0.09), compared with control rats. In rats that underwent 10-week WBV, stiffness tended to be increased (p = 0.07), and the serum level of osteocalcin decreased, compared with control rats. These findings suggest that 5-week WBV had beneficial effects on bone properties, and that increased bone mineral content and cortical bone geometry may lead to higher bone mechanical strength. Further studies will be needed to determine the optimal conditions of WBV for improving bone properties in the growth stage.
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Huesos , Vibración , Ratas , Masculino , Animales , Vibración/uso terapéutico , Huesos/diagnóstico por imagen , Densidad Ósea/fisiología , Hueso Esponjoso/diagnóstico por imagen , Hueso Cortical/diagnóstico por imagenRESUMEN
Introducción: Los GOS son prebióticos naturales presentes en la leche materna que pue-den obtenerse enzimáticamente a partir de la lactosa de leche de vaca durante la fabricación de yogur. El producto lácteo resultante será reducido en lactosa y contendrá prebióticos y bacterias potencialmente probióticas. Sin embargo, mantendrá la baja relación Ca/Pi que aporta la leche de vaca, lo que podría alterar el remodelamiento óseo y la mineralización. Objetivo: comparar si un yogur reducido en lactosa que contiene GOS (YE) ofrece ventajas adicionales respecto de un yogur regular sin GOS (YR) sobre las absorciones (Abs) de Ca y Pi, retención y calidad ósea durante el crecimiento normal. Al destete, ratas machos fueron divididas en 3 grupos alimentados con AIN Ì93-G (C), YE o YR durante 28 días. Resultados: YE mostró el mayor aumento de lactobacilos fecales; producción de ácidos grasos de cadena corta especialmente p, profundidad de las criptas colónicas y menor pH cecal. El %AbsCa y %AbsPi aumentó en el siguiente órden: YE> YR> C (p < 0,05). El contenido de Ca y Pi en fémur, la densidad y contenido mineral óseos y los parámetros biomecánicos fueron similares en YE y C, mientras que YR mostró valores significativa-mente menores (p < 0,05). Conclusiones: YE aumentó las Abs y biodisponibilidad de minerales, alcanzando la retención y calidad ósea de C. El aumento en las Abs observado en YR no logró obtener la retención y calidad ósea de C. Conclusión: YE habría contrarrestado el efecto negativo del mayor aporte de Pi de la leche de vaca y sería una buena estrategia para lograr el pico de masa ósea y calidad del hueso adecuados, especialmente en individuos intolerantes a la lactosa. (AU)
Breast milk contains an optimal calcium/phosphate (Ca/Pi) ratio and GOS. These natural prebiotics can be enzymatically produced via cow's milk lactose inyogurt manufacture. This milk product is low in lactose and contains prebiotics and potentially probiotic bacteria but maintains a low Ca/Pi ratio that could alter bone remodeling and mineralization. We evaluated if a lactose-reduced yogurt containing GOS (YE) offers additional advantages over regular yogurt without GOS (YR) on Ca and Pi absorption (Abs), bone retention and quality during normal growth. Weaning male rats were divided into 3 groups fed AIN'93-G (C), YE or YR for 28 days. Results: YE showed the highest increase in fecal lactobacilli; short-chain fatty acids production, especially propionate and butyrate; intestine crypt depth, and the lowest cecal pH. AbsCa% and AbsPi% increased in this order: YE> YR> C (p <0.05). Ca and Pi content in femur, bone density and mineral content, and biomechanical parameters were similar in YE and C, while YR showed the significantly lowest value (p < 0.05). Conclusions: YE increased mineral Abs reaching the retention and bone quality of C. Although YR increased Abs, bone retention and quality did not achieve C values. Seemingly, YE compensated for the negative effect of the higher Pi supply and would be a good strategy to achieve adequate peak bone mass and bone quality, especially in lactose intolerant individuals. (AU)
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Animales , Ratas , Oligosacáridos/metabolismo , Osteogénesis/fisiología , Calcio de la Dieta/farmacocinética , Fósforo Dietético/farmacocinética , Absorción Intestinal/fisiología , Lactosa/metabolismo , Magnesio/farmacocinética , Tibia/anatomía & histología , Yogur/análisis , Calcio de la Dieta/metabolismo , Absorciometría de Fotón , Densidad Ósea , Interpretación Estadística de Datos , Fósforo Dietético/metabolismo , beta-Galactosidasa/síntesis química , Ratas Wistar , Lactobacillus delbrueckii/aislamiento & purificación , Fémur/anatomía & histología , Intestino Grueso/anatomía & histología , Magnesio/metabolismo , Valor NutritivoRESUMEN
4-Hydroxy-2-nonenal (HNE) is an inducer of inflammation. The aim of this study was to elicit the link between the inhibition of HNE accumulation and the depression of inflammation whether dependent onl-arginine availability in growing rats. Male Wistar rats were fed with different levels of l-arginine at 250, 500, and 1000 mg/kg body weight for 14 days. The control group was fed with commercial pellets. After 14 days of oral administration, l-arginine significantly reduced hepatic accumulation of HNE and depressed inflammation in rats as compared with the control group. Compared to the control group, the anti-inflammatory action of l-arginine is reflected by upregulation of hepatic interleukin-10 (IL-10) and the suppression of hepatic cyclooxygenase-2, tumor necrotic factor α, IL-1ß, and IL-6 expressions in growing rats. With l-arginine administration, the activation of nuclear factor-κB (NF-κB) was efficaciously inhibited through the upregulation of inhibitory κBα, and the depression of phosphoinositide 3-kinase/protein kinase B (PI3K/Akt). In conclusion, this study demonstrated that l-arginine could reduce hepatic HNE levels and depress inflammation in growing rats, revealing a link between the inhibition of HNE accumulation with the depression of inflammation, which was attributed to the availability of l-arginine. A significant finding of this study was that the anti-inflammatory mechanism exerted by l-arginine was to inhibit NF-κB activation via downregulating PI3K/Akt.
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Aldehídos , Arginina , FN-kappa B , Aldehídos/metabolismo , Animales , Antiinflamatorios/farmacología , Arginina/farmacología , Inflamación/metabolismo , Masculino , FN-kappa B/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas WistarRESUMEN
Childhood obesity prevention is important to avoid obesity and its comorbidities into adulthood. Although the energy density of food has been considered a main obesogenic factor, a focus on food quality rather that the quantity of the different macronutrients is needed. Therefore, this study investigates the effects of changing the quality of carbohydrates from rapidly to slowly digestible carbohydrates on metabolic abnormalities and its impact on obesity in growing rats fed a high-fat diet (HFD). Growing rats were fed on HFD containing carbohydrates with different digestion rates: a HFD containing rapid-digesting carbohydrates (OBE group) or slow-digesting carbohydrates (ISR group), for 4 weeks and the effect on the metabolism and signaling pathways were analyzed in different tissues. Animals from OBE group presented an overweight/obese phenotype with a higher body weight gain and greater accumulation of fat in adipose tissue and liver. This state was associated with an increase of HOMA index, serum diacylglycerols and triacylglycerides, insulin, leptin, and pro-inflammatory cytokines. In contrast, the change of carbohydrate profile in the diet to one based on slow digestible prevented the obesity-related adverse effects. In adipose tissue, GLUT4 was increased and UCPs and PPARγ were decreased in ISR group respect to OBE group. In liver, GLUT2, FAS, and SRBP1 were lower in ISR group than OBE group. In muscle, an increase of glycogen, GLUT4, AMPK, and Akt were observed in comparison to OBE group. In conclusion, this study demonstrates that the replacement of rapidly digestible carbohydrates for slowly digestible carbohydrates within a high-fat diet promoted a protective effect against the development of obesity and its associated comorbidities.
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Methionine sulfoxide reductase (Msr) and glutathione (GSH) are two endogenous antioxidant systems for depressing oxidative stress. The aim of this study is to investigate the role of methionine in involving the stimulation of endogenous antioxidant capacity of rice protein (RP). Seven-week-old male Wistar rats (body weight 180-200 g) were fed with commercial pellets (as control), methionine, and RP for 2 weeks. Compared with control, GSH synthesis and expressions of MsrA, MsrB2, and MsrB3 were stimulated by methionine and RP. After 2 weeks of feeding, Nrf2 was activated by RP and methionine, whereas the expressions of Keap1 and Cul3 were depressed. The ARE-driven antioxidant expressions (GCLC, GCLM, GS, HO-1, NQO1, CAT, SOD, GR, GST, GPx) were upregulated by methionine and RP. Results suggest that the endogenous antioxidant response induced by RP is primarily attributed to the methionine availability, in which the stimulation of Msr and GSH antioxidant system via Nrf2-ARE pathway. PRACTICAL APPLICATIONS: Rice protein is a major plant protein, which is rich in sulfur-containing amino acids and widely consumed in the world. This paper emphasizes that the amino acid plays a key role in inducing the antioxidant activity of rice protein. The present study provides an insight that the methionine availability of rice protein will be a useful target for health promoting by activating endogenous antioxidant response against ROS-induced oxidative damage.
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Antioxidantes , Oryza , Proteínas de Vegetales Comestibles/administración & dosificación , Animales , Antioxidantes/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Hígado/metabolismo , Masculino , Metionina , Factor 2 Relacionado con NF-E2/metabolismo , Ratas , Ratas WistarRESUMEN
OBJECTIVES: To examine the effects of whole body vibration (WBV) on bone properties in growing rats, and to explore the optimal conditions for enhancing bone properties. METHODS: Thirty-six 4-week-old male rats were divided into 1 control and 5 experimental groups. Each experimental group underwent WBV at 15, 30, 45, 60, and 90â¯Hz (0.5â¯g, 15â¯min/d, 5â¯d/wk) for 8 weeks. We measured bone size, muscle weight and bone mechanical strength of the right tibia. Trabecular bone mass and trabecular bone microstructure (TBMS) of the left tibia were analyzed by micro-computed tomography. Serum levels of bone formation/resorption markers were also measured. RESULTS: WBV at 45â¯Hz and 60â¯Hz tended to enhance trabecular bone mass and TBMS parameters. However, there was no difference in maximum load of tibias among all groups. Serum levels of bone resorption marker were significantly higher in the 45-Hz WBV group than in the control group. CONCLUSIONS: WBV at 45-60â¯Hz may offer a potent modality for increasing bone mass during the period of rapid growth. Further studies are needed to explore the optimal WBV conditions for increasing peak bone mass and TBMS parameters. WBV modality may be a potent strategy for primary prevention against osteoporosis.
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True ileal digestibility (TID) values of amino acid (AA) obtained using growing rats are often used for the characterisation of protein quality in different foods and acquisition of digestible indispensable amino acid scores (DIAAS) in adult humans. Here, we conducted an experiment to determine the TID values of AA obtained from nine cooked cereal grains (brown rice, polished rice, buckwheat, oats, proso millet, foxtail millet, tartary buckwheat, adlay and whole wheat) fed to growing Sprague-Dawley male rats. All rats were fed a standard basal diet for 7 d and then received each diet for 7 d. Ileal contents were collected from the terminal 20 cm of ileum. Among the TID values obtained, whole wheat had the highest values (P<0·05), and polished rice, proso millet and tartary buckwheat had relatively low values. The TID indispensable AA concentrations in whole wheat were greater than those of brown rice or polished rice (P<0·05), and polished rice was the lowest total TID concentrations among the other cereal grains. The DIAAS was 68 for buckwheat, 47 for tartary buckwheat, 43 for oats, 42 for brown rice, 37 for polished rice, 20 for whole wheat, 13 for adlay, 10 for foxtail millet and 7 for proso millet. In this study, the TID values of the nine cooked cereal grains commonly consumed in China were used for the creation of a DIAAS database and thus gained public health outcomes.
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Aminoácidos/metabolismo , Digestión , Grano Comestible/química , Animales , China , Dieta , Fagopyrum/química , Íleon/metabolismo , Masculino , Mijos/química , Oryza/química , Proteínas de Vegetales Comestibles/análisis , Ratas , Ratas Sprague-Dawley , Triticum/químicaRESUMEN
OBJECTIVES: To examine the effects of whole body vibration (WBV) on bone properties in growing rats, and to explore the optimal conditions for enhancing bone properties. METHODS: Thirty-six 4-week-old male rats were divided into 1 control and 5 experimental groups. Each experimental group underwent WBV at 15, 30, 45, 60, and 90 Hz (0.5 g, 15 min/d, 5 d/wk) for 8 weeks.We measured bone size, muscle weight and bone mechanical strength of the right tibia. Trabecular bone mass and trabecular bone microstructure (TBMS) of the left tibia were analyzed by micro-computed tomography. Serum levels of bone formation/resorption markers were also measured. RESULTS: WBV at 45 Hz and 60 Hz tended to enhance trabecular bone mass and TBMS parameters. However, there was no difference in maximum load of tibias among all groups. Serum levels of bone resorption marker were significantly higher in the 45-Hz WBV group than in the control group. CONCLUSIONS: WBV at 45–60 Hz may offer a potent modality for increasing bone mass during the period of rapid growth. Further studies are needed to explore the optimal WBV conditions for increasing peak bone mass and TBMS parameters. WBV modality may be a potent strategy for primary prevention against osteoporosis.
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Animales , Humanos , Masculino , Ratas , Resorción Ósea , Osteoporosis , Prevención Primaria , Tibia , VibraciónRESUMEN
Osteoprotegerin (OPG), receptor activator of NF-κB ligand (RANKL), and parathyroid hormone (PTH) play a central role in the regulation of bone turnover in chronic kidney disease (CKD), but their influence on bone mineral density (BMD) and strength remains unclear, particularly in children. We studied the clinical significance of OPG and RANKL in relation to PTH, femur weight, BMD, and bone biomechanical properties in growing rats after one month (CKD-1) and three months (CKD-3) of surgically-induced mild CKD. Gene expression of parathyroid hormone 1 receptor (PTH1R) and activating transcription factor 4 (ATF4), major regulators of anabolic PTH response in bone, was also determined. Serum PTH and bone PTH1R/ATF4 expression was elevated in CKD-3 compared with other groups, and it positively correlated with femur weight, BMD, and the biomechanical properties of the femoral diaphysis reflecting cortical bone strength. In contrast, bone RANKL/OPG ratios were decreased in CKD-3 rats compared with other groups, and they were inversely correlated with PTH and the other abovementioned bone parameters. However, the PTH-PTH1R-ATF4 axis exerted an unfavorable effect on the biomechanical properties of the femoral neck. In conclusion, this study showed for the first time an inverse association between serum PTH and the bone RANKL/OPG system in growing rats with mild CKD. A decrease in the RANKL/OPG ratio, associated with PTH-dependent activation of the anabolic PTH1R/ATF4 pathway, seems to be responsible for the unexpected, beneficial effect of PTH on cortical bone accrual and strength. Simultaneously, impaired biomechanical properties of the femoral neck were observed, making this bone site more susceptible to fractures.
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Huesos/metabolismo , Osteoprotegerina/metabolismo , Hormona Paratiroidea/metabolismo , Ligando RANK/metabolismo , Receptor de Hormona Paratiroídea Tipo 1/metabolismo , Uremia/metabolismo , Factor de Transcripción Activador 4/genética , Factor de Transcripción Activador 4/metabolismo , Animales , Fenómenos Biomecánicos , Densidad Ósea , Fémur/metabolismo , Regulación de la Expresión Génica , Masculino , Tamaño de los Órganos , Osteoprotegerina/sangre , Hormona Paratiroidea/sangre , Ligando RANK/sangre , Ratas Wistar , Receptor de Hormona Paratiroídea Tipo 1/genética , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/diagnóstico por imagen , Insuficiencia Renal Crónica/patología , Uremia/sangre , Uremia/genética , Microtomografía por Rayos XRESUMEN
The purpose of this study was to examine the effects of green tea extract (GTE) intake on bone structural and physiological properties, such as bone mass, trabecular bone microarchitecture, cortical bone geometry, and bone mechanical strength, in growing rats. Four-week-old male Wistar rats were divided into the following four groups: standard diet feeding for 85 days (S-CON) or 170 days (L-CON), and GTE diet feeding for 85 days (S-GTE) or 170 days (L-GTE). At the end of the experiment, in addition to measurement of circulating bone formation/resorption markers, bone mass, trabecular bone microarchitecture, and cortical bone geometry were analyzed in the left femur, and bone mechanical strength of the right femur was measured. There was no difference in all bone parameters between the S-CON and S-GTE groups. On the other hand, the L-GTE group showed the decrease in some trabecular bone mass/microarchitecture parameters and no change in cortical bone mass/geometry parameters compared with the L-CON group, and consequently the reduction in bone weight corrected by body weight. There was no difference in bone formation/resorption markers and bone mechanical strength between the S-CON and S-GTE groups and also between the L-CON and L-GTE groups. However, serum leptin levels were significantly lower in the L-GTE group than in the L-CON group. Thus, the long-term GTE intake had negative effects on bone, especially trabecular bone loss and microarchitecture mal-conformation, in growing rats.
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Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Fémur/crecimiento & desarrollo , Té/efectos adversos , Animales , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Densidad Ósea/fisiología , Hueso Cortical/crecimiento & desarrollo , Fémur/efectos de los fármacos , Leptina/metabolismo , Masculino , Ratas , Ratas WistarRESUMEN
OBJECTIVES: The aim of this study was to investigate the effects of soy isoflavone on tibia length, bone mineral density (BMD), and structural parameters in growing female rats. METHODS: Three-week-old female Sprague-Dawley rats were randomly assigned to four experimental groups: control (CON: distilled water gavage); low-dose isoflavone (low-IF: 10 mg/kg body weight [BW]/d gavage); high-dose isoflavone (high-IF: 50 mg/kg BW/d gavage); and 17 ß-estradiol (E2: subcutaneous injection of 10 µg). All animals received a soy-free diet and vaginal opening was monitored daily. After an 8-wk treatment period, bone-related parameters (alkaline phosphatase [ALP], osteocalcin [OC], N-terminal telopeptide [NTx], bone length, failure load, stiffness, BMD, and structural parameters) were analyzed. RESULTS: Serum ALP levels of the high-IF group were higher than those of the CON group (P < 0.05); however, serum OC levels of the high-IF group were lower than those of the CON, low-IF, and E2 groups (P < 0.05). The tibias and femurs of the low-IF group were longer than those of the CON and high-IF groups (P < 0.05). Bone volume, trabecular number, and BMD of trabecular bone of the high-IF and E2 groups were higher than those of the CON and low-IF groups (P < 0.05). The trabecular thickness of the high-IF group was higher than that of the CON and low-IF groups (P < 0.05). The failure load of the high-IF group was higher than those of the CON group (P < 0.05). Age and body weight at vaginal opening of the E2 group were significantly lower than those of the CON, low-IF, and high-IF groups (P < 0.05). CONCLUSIONS: This study suggests that 8 wk of low-dose supplementation with soy isoflavone stimulates longitudinal bone growth. Additionally, high-dose supplementation with soy isoflavone may improve bone quality (BMD and structural parameters) in growing female rats.
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Desarrollo Óseo/efectos de los fármacos , Fémur/efectos de los fármacos , Isoflavonas/farmacología , Tibia/efectos de los fármacos , Fosfatasa Alcalina/sangre , Animales , Biomarcadores/sangre , Biomarcadores/orina , Peso Corporal , Densidad Ósea , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Estradiol/farmacología , Femenino , Osteocalcina/sangre , Fragmentos de Péptidos/orina , Ratas , Ratas Sprague-Dawley , Glycine max/químicaRESUMEN
Compared with the extensor digitorum longus (EDL) muscle of control rats (C), the EDL muscle of rats fed a low-protein, high-carbohydrate diet (LPHC) showed a 36% reduction in mass. Muscle mass is determined by the balance between protein synthesis and proteolysis; thus, the aim of this work was to evaluate the components involved in these processes. Compared with the muscle from C rats, the EDL muscle from LPHC diet-fed rats showed a reduction (34%) in the in vitro basal protein synthesis and a 22% reduction in the in vitro basal proteolysis suggesting that the reduction in the mass can be associated with a change in the rate of the two processes. Soon after euthanasia, in the EDL muscles of the rats fed the LPHC diet for 15days, the activity of caspase-3 and that of components of the ubiquitin-proteasome system (atrogin-1 content and chymotrypsin-like activity) were decreased. The phosphorylation of p70(S6K) and 4E-BP1, proteins involved in protein synthesis, was also decreased. We observed an increase in the insulin-stimulated protein content of p-Akt. Thus, the higher insulin sensitivity in the EDL muscle of LPHC rats seemed to contribute to the lower proteolysis in LPHC rats. However, even with the higher insulin sensitivity, the reduction in p-E4-BP1 and p70(S6K) indicates a reduction in protein synthesis, showing that factors other than insulin can have a greater effect on the control of protein synthesis.
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Caspasa 3/metabolismo , Dieta de Carga de Carbohidratos/efectos adversos , Dieta con Restricción de Proteínas/efectos adversos , Regulación hacia Abajo , Resistencia a la Insulina , Músculo Esquelético/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Animales , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Pie , Péptidos y Proteínas de Señalización Intracelular , Masculino , Desarrollo de Músculos , Músculo Esquelético/enzimología , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilación , Biosíntesis de Proteínas , Procesamiento Proteico-Postraduccional , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas/metabolismo , Proteolisis , Distribución Aleatoria , Ratas Wistar , Proteínas Quinasas S6 Ribosómicas 70-kDa/genética , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , UbiquitinaciónRESUMEN
Adipocytes, cells of white fat tissue, store energy in the form of lipids and have also endocrine functions. Disturbances in adipocyte metabolism lead to decreased or excessive fat tissue accumulation and are associated with numerous diseases. Pathologic alterations in adipose tissue are known to develop with age, however, changes in young, growing subjects are poorly elucidated. In the present study, glucose transport and metabolism, hyperpolarization of the inner mitochondrial membrane and the lipolytic activity were compared in the epididymal adipocytes of 8-week-old and 16-week-old rats. It was demonstrated that glucose conversion to lipids, glucose transport and oxidation was decreased in the adipocytes of the older animals. These effects were accompanied by increase in lactate release and by decrease in hyperpolarization of the mitochondrial membrane. Lipolytic response to epinephrine was increased (at lower concentrations of the hormone) or reduced (at higher concentration) in the adipocytes of the older rats. However, induction of lipolysis by the direct activation of protein kinase A induced similar response. It was also demonstrated that inhibition of phosphodiesterase 3B or adenosine A1 receptor blocking caused lower lipolysis in the cells of the older rats. Moreover, antilipolytic action of insulin was impaired in the adipocytes of these rats, probably due to changes in the initial steps of the insulin signaling pathway. However, the use of the pharmacologic inhibitor of protein kinase A instead of insulin resulted in similar antilipolysis in both groups of cells. These results show that, in spite of relatively small age difference, substantial changes in adipose tissue metabolism develop in these animals. Decreased response to insulin action seems to be particularly relevant finding.
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Adipocitos/metabolismo , Envejecimiento/metabolismo , Glucosa/metabolismo , Lipólisis/fisiología , Potencial de la Membrana Mitocondrial/fisiología , Membranas Mitocondriales/metabolismo , Antagonistas del Receptor de Adenosina A1/farmacología , Animales , Transporte Biológico Activo/efectos de los fármacos , Transporte Biológico Activo/fisiología , Epinefrina/farmacología , Lipólisis/efectos de los fármacos , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Inhibidores de Fosfodiesterasa 3/farmacología , Ratas , Ratas WistarRESUMEN
The degree of accumulation and distribution of Cd and Pb in the organs of young animals compared to the amount taken in with water or feed have not been thoroughly investigated yet. The experiment aimed to verify whether the source of toxic metals (feed, drinking water) administered to growing rats orally has an influence on the degree of accumulation of Cd and Pb in the organs (brain, spleen, lungs, heart, liver and kidneys). The rats received Cd and/or Pb respectively in the amount of 7 mg and/or 50 mg per 1 kg of feed or per 1 L of distilled water. The rats' organs accumulated in total about 0.5 % Cd and about 0.71 % Pb consumed with water and about 0.46 % Cd and about 0.63 % Pb taken in with feed. More than 60 % of Cd and more than 70 % of Pb absorbed by the studied organs was accumulated in the liver, and more than 30 % of Cd and 26-29 % of Pb in the kidneys and less than 1 % in other organs. The relationship between the distribution percentage of Cd in the studied organs can be presented as: liver > kidneys > brain > lungs > heart > spleen. The relationship between the distribution percentage of Pb can be presented as: liver > kidneys > brain > spleen > heart > lungs. Significantly (P < 0.05), more Cd and Pb were accumulated in total in the organs of rats receiving the metals in drinking water.
Asunto(s)
Envejecimiento/metabolismo , Alimentación Animal , Cadmio/farmacocinética , Agua Potable , Contaminación de Alimentos/análisis , Plomo/farmacocinética , Alimentación Animal/análisis , Animales , Cadmio/administración & dosificación , Agua Potable/análisis , Plomo/administración & dosificación , Masculino , Especificidad de Órganos , Ratas Wistar , Distribución TisularRESUMEN
The purpose of the present study was to investigate the bone-conserving effects of Rubus coreanus-Cheonggukjang (RC-CGJ) supplemented with more intensified phytochemicals compared to general Cheonggukjang (CGJ) in growing rats. Eighteen rats were divided into 3 treatment groups (Control, CGJ, and RC-CGJ) and were given experimental diets for 9 weeks. All of the rats in this study were fed a AIN-93G-based diet. Both CGJ groups were fed with 33.1% CGJ and RC-CGJ powder, respectively. The results of this study indicate that weight gain, mean food intake, and food efficiency ratio were not significantly different by the experimental diets among all groups. Spine bone mineral density (BMD) and femur BMD were not significantly different by the experimental diets. Spine bone mineral content (BMC) was significantly higher in the RC-CGJ and CGJ groups than in the control group, regardless of CGJ type. The femur BMC of the CGJ supplemented group was significantly higher compared with the control group and the RC-CGJ group. Compared with the control group, spine BMD and femur BMD per weight were markedly increased in the RC-CGJ and CGJ group regardless of CGJ type. Also, spine BMC per weight was significantly higher in the RC-CGJ group than in the CGJ group. However, femur BMC per weight was significantly higher in the CGJ group than in the RC-CGJ group. It can be concluded that RC-CGJ and CGJ supplemented diets have more beneficial effects on spine and femur peak bone mass in growing rats.
RESUMEN
PURPOSE: The objective of this study was to investigate the effects of a high fructose and fat diet on bone growth and maturation in growing female rats. METHODS: Three-week-old female SD rats were randomly assigned to four experimental groups; the control group (CON: fed control diet based on AIN-93G, n = 8); the high-fructose diet group (HFrc: fed control diet with 30% fructose, n = 8); the high-fat diet group (Hfat: fed control diet with 45 kcal% fat, n = 8); and the high-fat diet plus high fructose group (HFrc + HFat: fed diets 45 kcal% fat with 30% fructose, n = 8). Each group was assigned their respective diets for the remaining eight weeks. Bone-related parameters (bone mineral density (BMD) and structural parameters, osteocalcin (OC), deoxypyridinoline (DPD)) and morphologic changes of kidney were analyzed at the end of the experiment. RESULTS: Final body weights and weight gain were higher in the HFat and HFrc + HFat groups and showed higher tendency in the HFrc group compared with those of the CON group (p < 0.05); however, no significant difference in caloric intake was observed among the four experimental groups. The serum OC levels of the HFrc and HFrc + HFat groups were lower than those of the CON and HFat groups (p < 0.05). Urinary levels of DPD did not differ among the experimental groups. BV/TV and Tb.N of trabecular bone were higher in the HFrc + HFat group and showed a higher tendency in the HFrc group than those of the CON and HFat groups (p < 0.05). Tb.Pf of trabecular bone were lower in the HFrc + HFat group than those in the CON and HFat groups (p < 0.05). However, no difference in trabecular BMD was observed among the experimental groups. Cortical bone volume was higher in the HFat and HFrc + HFat groups than in the CON and HFrc groups (p < 0.05). No morphology change in kidney was observed among the experimental groups. CONCLUSION: Our study suggests that 8 weeks of high-fructose and high fat intake could improve the bone quality (Structural parameters) of trabecular and cortical bone of tibia in growing female rats.
Asunto(s)
Animales , Femenino , Humanos , Ratas , Peso Corporal , Desarrollo Óseo , Dieta , Dieta Alta en Grasa , Ingestión de Energía , Fructosa , Riñón , Osteocalcina , Tibia , Aumento de PesoRESUMEN
The our objective was to investigate the adaptations induced by a low-protein, high-carbohydrate (LPHC) diet in growing rats, which by comparison with the rats fed a control (C) diet at displayed lower fasting glycemia and similar fasting insulinemia, despite impairment in insulin signaling in adipose tissues. In the insulin tolerance test the LPHC rats showed higher rates of glucose disappearance (30%) and higher tolerance to overload of glucose than C rats. The glucose uptake by the soleus muscle, evaluated in vivo by administration of 2-deoxy-[(14)C]glucose, increased by 81%. The phosphoenolpyruvate carboxykinase content and the incorporation of [1-(14)C]pyruvate into glucose was also higher in the slices of liver from the LPHC rats than in those from C rats. The LPHC rats showed increases in l-lactate as well as in other gluconeogenic precursors in the blood. These rats also had a higher hepatic production of glucose, evaluated by in situ perfusion. The data obtained indicate that the main substrates for gluconeogenesis in the LPHC rats are l-lactate and glycerol. Thus, we concluded that the fasting glycemia in the LPHC animals was maintained mainly by increases in the hepatic gluconeogenesis from glycerol and l-lactate, compensating, at least in part, for the higher glucose uptake by the tissues.