ABSTRACT
Objective:To explore the effect of aerobic exercise on the food intake of obesity rats and obesity resistant rats and some mechanisms Method:The four years old Sprague-Dawley rats were randomly divided into standard chow group (C) and high-fat diet group.After 10 weeks feeding,the obese group (OB group) and obesity resistant group (OR group) induced by high-fat diet were screened out.Then all the rats in OB group and OR group were respectively and randomly divided into exercise rats (OB-Sw group,OR-Sw group) and non-exercise rats (OB-Sed group,OR-Sed group).Aerobic swimming exercise for the exercise rats was defined as 60％ of individual exhaustion exercise intensity,45 minutes per day,5 times per week.Meanwhile,the body weight and food intake of the exercise and non-exercise rats were monitored every week.After 8 weeks intervention,the serum and gastric tissue of rats were obtained,and then the TG,TC,LDL-c,HDL-c in serum and the expression of ghrelin in gastric tissue were detected.Result:Ten weeks later,the body weight of the rats with high-fat diet showed a significant difference compared with the rats with standard chow group (P ＜ 0.05).The content of LDL in OB-Sed group was significantly higher than that in C group (P＜0.05).After 8 weeks aerobic exercise,for the food intake,OB-Sed group was higher than OB-Sw group and OR-Sed group was higher than OB-Sw group.The expression of ghrelin in gastric tissue in OB-Sed group and OR-Sed group was higher than that in OB-Sw group,OB-Sw group and C group.Conclusion:Exercise might reduce the food intake of obesity rats and obesity resistant rats by reducing the expression of ghrelin in stomach.
ABSTRACT
O sobrepeso induzido por uma dieta rica em gordura atrasa a cicatrização através do prolongamento da fase inflamatória, entretanto, quando recebem uma dieta obesogênica, alguns ratos são suscetíveis a desenvolver sobrepeso, enquanto outros são resistentes. Drogas anti-inflamatórias não-esteróides são frequentemente utilizadas para reduzir a inflamação. Este estudo investigou a cicatrização cutânea em ratos propensos a obesidade induzida por dieta (DIO) e em ratos resistentes a dieta (DR) e avaliou a participação da administração do celecoxibe na cicatrização cutânea destes animais. Ratos machos foram alimentados com uma dieta padrão (Controle, C) ou com uma dieta rica em gordura saturada (30%). Após 19 semanas, o grupo experimental foi subdividido nos grupos DIO e DR. Uma lesão excisional foi feita e os animais foram mortos 7 ou 14 dias depois. Os grupos tratados receberam uma dose diária de 5 ou 10 mg/kg/dia de celecoxibe a partir de dois dias antes da lesão até 7 dias após a lesão, quando foram mortos. O peso corporal foi maior no grupo DIO comparado aos grupos C e DR. A gordura retroperitoneal foi maior no grupo DIO do que nos grupos C e DR e foi maior no grupo DR do que no grupo C. O tratamento com o celecoxibe não alterou o maior peso corporal apresentado pelo grupo DIO ou a maior porcentagem de gordura retroperitoneal apresentada pelos grupos DIO e DR. Todos os grupos tratados com celecoxibe 10 mg apresentaram atraso na cicatrização e não foram mais analisados. O grupo DIO apresentou intolerância a glicose, e ambos os grupos DIO e DR apresentaram atraso na contração e na reepitelização da lesão. O tratamento com celecoxibe 5 mg reverteu a intolerância a glicose no grupo DIO e a contração atrasada nos grupos DIO e DR. Comparado ao grupo DR, o grupo DIO apresentou maior quantidade de células inflamatórias, assim como maiores níveis de peroxidação lipídica. O tratamento com celecoxib (5 mg) não reduziu o número de PMN, mas reduziu o número de mastócitos...
Overweight induced by high-fat diet delays wound healing through elongation of inflammatory phase, however, when receiving on obesogenic diet, some rats are susceptible to developing the overweight phenotype, whereas others are resistant. Nonsteroidal anti-inflammatory drugs are frequently used to reduce the inflammation. This study investigated cutaneous wound healing in diet-induced obesity (DIO)-prone and diet-resistant (DR) rats and evaluated the contribution of celecoxib administration on cutaneous wound healing of these animals. Male rats were fed with a standard (Control, C) or high-saturated fat (30%) diet. After 19 weeks, experimental group was subdivided into DIO and DR groups. An excisional lesion was made and the animals were killed 7 or 14 days later. Treated groups received a daily dose of celecoxib 5 or 10 mg/kg/day from two days before wounding until 7 days after wounding when were killer. The body weight was higher in the DIO group compared to the C and DR groups. Retroperitoneal fat was higher in the DIO group than in the C and DR groups and was higher in the DR group than in the C group. Celecoxib-treatment did not alter the higher body weight presented by DIO group of higher retroperitoneal fat percentage displayed by DIO and DR groups. All groups treated with celecoxib 10 mg showed delayed wound healing, and weren't further analysed. The DIO group presented glucose intolerance, and both the DIO and DR groups presented delayed wound contraction and re-epithelialisation. The celecoxib 5 mg-treatment reversed the glucose intolerance in the DIO group and the delayed contraction in the DIO and DR groups. Compared to the DR group, the DIO group displayed higher amounts of inflammatory cells as well as higher levels of lipid peroxidation. Celecoxib-treatment (5 mg) did not reduce the number of PMN, but reduce mast cells number in DIO group and macrophages number and lipid peroxidation in both groups. Myofibroblastic differentiation...
Subject(s)
Rats , Anti-Inflammatory Agents, Non-Steroidal , Cyclooxygenase 2 Inhibitors , Wound Healing/physiology , Dietary Fats/administration & dosage , Lipid Metabolism/physiology , Obesity/etiology , Obesity/metabolism , Obesity/drug therapy , Skin/injuries , Overweight/chemically induced , Rats, WistarABSTRACT
OBJETIVO: Desenvolver uma dieta hiperlipídica de baixo custo, tendo farinha de soja como fonte proteica, que seja eficiente na seleção de ratos propensos e resistentes à obesidade e que permita alcançar fenótipo obeso nos animais propensos. Além desses requisitos, a dieta deve ser palatável e não rejeitada a curto prazo pelo animal. MÉTODOS: A dieta proposta foi obtida misturando-se leite condensado (15,5 por cento), amendoim (18,5 por cento), farinha de soja (20,0 por cento), óleo de milho (6,0 por cento), ração Bio Tec (30,0 por cento) e bolacha wafer de chocolate (10,0 por cento). A mistura foi peletizada e submetida à análise bromatológica. A dieta foi ofertada a ratos Wistar durante uma semana; posteriormente, os animais foram divididos em três grupos, de acordo com o ganho de peso. O terço superior foi considerado propenso à obesidade e o terço inferior, resistente à obesidade. Após 80 dias de oferta da dieta, os animais foram sacrificados e foram quantificados o peso corpóreo, consumo alimentar, gorduras retroperitoneal, periepididimal, de carcaça e gorduras totais. RESULTADOS: Verificou-se que a dieta apresentava 5,31kcal/g, com a seguinte composição: 22,3 por cento de gordura, 22,2 por cento de proteína, 15,9 por cento de fibra, estimando-se 35,7 por cento de carboidrato. Ratos propensos à obesidade, alimentados por 87 dias com a dieta hipercalórica, apresentaram peso corpóreo, gorduras retroperitoneal, periepididimal e totais significativamente maiores do que animais resistentes à obesidade (p<0,05). O consumo de alimentos também foi maior em animais propensos (p<0,05). Verificou-se também que a substituição da caseína pela farinha de soja, como componente proteico da ração, levou à diminuição de 96,0 por cento no custo do estudo. CONCLUSÃO: A dieta formulada com farinha de soja apresentou custo reduzido e foi capaz de desenvolver o fenótipo obeso em ratos propensos, à semelhança do observado na literatura com outras dietas.
OBJECTIVE: The objective was to develop a high-fat, low cost diet, using soybean meal as protein source. This diet should effectively discriminate between rats prone and resistant to obesity and allow the obese phenotype to be achieved in the animals that are prone to obesity. Furthermore, the diet must be palatable and not be rejected by the animal in the short run. METHODS: The chow was obtained by mixing the following ingredients: condensed milk (15.5 percent), peanuts (18.5 percent), soybean meal (20.0 percent), corn oil (6.0 percent), Bio Tec chow (30.0 percent) and chocolate wafer cookies (10.0 percent). In order to make it appropriate for rats, the mixture was pelleted and subjected to food analysis. The chow was offered to Wistar rats for a week. The animals were subsequently separated according to weight gained. The upper third group was considered prone to obesity and the lower third group was considered resistant to obesity. The animals were sacrificed 80 days later to determine body weight, food intake, retroperitoneal, periepididymal and carcass fats and total fats. RESULTS: Food analysis found that the chow had an energy density of 5.31 Kcal/g, 22.3 percent fat, 22.2 percent protein, 15.9 percent fiber and 35.7 percent carbohydrates. After being fed for 87 days with the high-fat diet, obesity-prone rats had higher body weight and retroperitoneal, periepididymal and total fats than obesity-resistant animals (p<0.05). Food intake was also higher among obesity-prone rats (p<0.05). The replacement of casein by soybean meal as protein source reduced the cost of the study by 96.0 percent. CONCLUSION: The substitution of casein by soybean meal in a high-fat diet allows cost reduction and the identification of obese-prone rats. Continuous use of this high-fat diet resulted in the development of the obese phenotype, as seen with other diets used in the literature.
ABSTRACT
Objective: To observe the changes of non-alcoholic fatty liver related indices in diet-induced obesity-resistant rats and diet-induced obesity rats. Methods: A total of 140 male Sprague Dawley(SD) rats were randomly divided into normal control group (n=20, normal diet for 8 weeks) and model group (n = 120, high fat diet for 8 weeks). The rats of model group were further divided into 2 groups, O-N (obesity with non-alcoholic fatty liver) and OR-N (obesity-resistance with non-alcoholic fatty liver) groups. The rats with body mass higher than mean +1.96 folds standard deviation were included in O-N group and those with body mass lower than mean +1.0 fold standard deviation were included in OR-N group. The animals with the top 20 weight gains in the O-N group and those with the least 20 weight gains in OR-N group were used in the present study. The general conditions and weight changes of rats were dynamically observed for 8 weeks. Eight rats were sacrificed in each group at the end of the 8th week and the following indices were compared among the three groups, including serum levels of alanine aminotransferase (ALT), total cholesterol(TC), triglyceride(TG), high-density lipoprotein (HDL), insulin sensitivity index (ISI), leptin, energy utilization and body fat ratio. The pathological changes of liver tissues were observed by H-E staining. Results: The weight difference of rats in the O-N group and the OR-N group gradually increased; at the end of the 8th week, the weight of rats in O-N group was significantly higher than those in the OR-N group and the normal control group(P<0.01). The serum levels of ALT, TG, and leptin were significantly increased in both O-N and OR-N groups (P<0.05, P<0.01). The TC, TG, leptin levels and energy utilization in O-N group were significantly higher than those in OR-N group (P<0.05, P< 0.01). The HDL and ISI levels in the O-N group were significantly lower than those in the OR-N and normal control groups (P<0.01, P<0.05). Light microscopy showed a great number of fat vacuoles in the liver cells of O-N and OR-N groups. Conclusion: High fat diets can induce SD rat to develop non-alcoholic fatty liver with obesity and obesity-resistance. Increase in serum leptin and ISI may play a role in resisting diet-induced obesity and non-alcoholic fatty liver of rats.