Cafeteria diet intake for fourteen weeks can cause obesity and insulin resistance in Wistar rats

OBJECTIVE: Obesity is a strong predictor of some kinds of diseases. High intake of high-fat foods contributes significantly to the growth of the obese population globally. The aim of this study was to verify if consumption of a cafeteria diet for fourteen weeks could increase white fat mass, body weight and skeletal muscle mass and promote insulin resistance in male Wistar rats. METHODS: Twenty animals were divided into two groups: control and obese. Both were fed standard chow and water ad libitum. Additionally, a cafeteria diet consisting of bacon, bologna sausage, sandwich cookies and soft drink was given to the obese group. RESULTS: The obese group was significantly heavier (p<0.0001) than controls from the second week until the end of the cafeteria-diet intervention. Absolute and relative fat mass, liver weight and Lee Index increased significantly (p<0.05) in the obese group. Furthermore, the obese group had lower (p<0.05) insulin sensitivity than the control group. CONCLUSION: In conclusion, fourteen weeks of cafeteria diet promoted a progressive increase of fat mass and insulin resistance. Therefore, this is a great and inexpensive diet-induced insulin resistance model.

OBJETIVO: A obesidade é um forte preditor de alguns tipos de doenças. A grande oferta de comida e a predominância de ácidos graxos presentes na maioria dos alimentos contribuem diretamente para o aumento da população obesa no mundo. O objetivo do estudo foi verificar se uma dieta de cafeteria durante um período de catorze semanas pode causar aumento dos pesos de tecido adiposo branco, corporal e muscular e provocar um quadro de resistência insulínica em ratos machos Wistar. MÉTODOS: Vinte ratos machos Wistar foram divididos em dois grupos: controle e obeso. Os dois grupos foram alimentados com ração padrão e água ad libitum. Ao grupo obeso foi ofertada dieta ocidental, composta por salsicha, mortadela, bolacha recheada, bacon e refrigerante. RESULTADOS: Os animais do grupo obeso estavam significantemente mais pesados a partir da segunda semana de tratamento e essa diferença permaneceu até o final do estudo (p<0,0001). O peso absoluto e relativo do tecido adiposo branco e do fígado, e o Índice de Lee foram maiores no grupo obeso (p<0,05), que apresentou uma menor sensibilidade à insulina no final do estudo quando comparado ao grupo controle (p<0,05). Podemos observar que a dieta cafeteria promoveu um aumento progressivo e significativo da massa de gordura corporal associada à disfunção da ação da insulina. CONCLUSÃO: Conclui-se que uma dieta de cafeteria por um período de catorze semanas é capaz de promover aumento progressivo da massa adiposa associada à disfunção da insulina, sendo ótimo e fácil modelo de para induzir resistência à insulina.

Gastric Perfusion of Vitamin D3 with Different Diets Induce the Atherosclerotic Rat Model / 中国康复理论与实践

@#ObjectiveTo investigate the optimun approach to induce the atherosclerotic rat model.MethodsThree methods were used to induce atherosclerotic model, including: simple high fat diet feeding, high fat diet feeding with gastric perfusion of Vitamin D3, and gastric perfusion of Vitamin D3 with common rat food (splashed oil on the normal rat food with yolks and peanuts). Histopathology change of the atherosclerotic plaques in aorta was observed by normal and histopathologic sections and Hematoxylin staining.ResultsThe endarterium of aorta of the rats with simple high fat diet was smooth without atherosclerotic plaques after 2 months. 2 rats with high fat diet feeding and gastric perfusion of Vitamin D3 had formed miliary atherosclerotic plaques. In the rats with vitamin D3 and common rat food, the ring-shape calcified atherosclerotic plaques were found in the all endarterium of aorta.ConclusionGastric perfusion of Vitamin D3 once a week (3 times) combined with common rat diet could induce the atherosclerotic model successfully and decrease the mortality rate.