EFEITO DO EXERCÍCIO DE FORÇA NA COMPOSIÇÃO CORPORAL DE RATOS OBESOS

O presente estudo buscou analisar o efeito do exercício de força na composição corporal de ratos acometidos por obesidade, induzida por dieta hipercalórica. Foram utilizados 12 ratos, divididos em dois grupos: Controle Treinamento (CT, n=6) e Obeso Treinamento (OT, n=6). Os animais do grupo CT apresentaram valor reduzido do índice de Lee e IMC, além de menor quantidade de tecido adiposo epididimal em relação ao OT. Portanto conclui-se que esta forma de exercício pode auxiliar no combate a obesidade, entretanto, salienta-se que além do exercício, a dieta exerce papel fundamental na redução de peso corporal, sendo a associação de exercício e dieta adequada, a forma mais eficaz na redução do peso corporal

EFEITO DO DESTREINAMENTO SOBRE A COMPOSIÇÃO CORPORAL DE RATOS SUBMETIDOS À DIETA PADRÃO E HIPERCALÓRICA

O objetivo do estudo foi verificar o efeito do destreinamento sobre a composição corporal de ratos submetidos à dieta hiperlipídica e dieta padrão com ração. Foram utilizados 30 ratos machos, divididos nos grupos Controle Sedentário (CS) e Controle Exercício Destreinado (CEd), Obeso Sedentário (OS) e Obeso Exercício Destreinado (OEd), que realizaram treinamento de saltos, com 3 x 12 repetições, 3x/semana, por oito semanas. Em seguida, permaneceram por mais oito semanas sem realizar atividade física. Foram mensurados comprimento e peso dos animais. Em seguida, foram eutanasiados e retirado o tecido adiposo epididimal. Foram calculados: Tecido Adiposo Epidimal (TecAdp) total (g) e percentual (%), Índice de Lee e Índice de Massa Corporal (IMC). Os animais dos grupos CS e CEd apresentaram menor ganho de peso em relação aos animais dos grupos OS e OEd. Além disso, o grupo CEd demonstrou valores de TecAdp (totais e percentuais) e IMC, inferiores aos dos grupos OS e OEd

ANÁLISE MORFOLÓGICA DOS PROCESSOS PATOLÓGICOS GERAIS EM RINS DE RATOS OBESOS E SUA RELAÇÃO COM O EXERCÍCIO FÍSICO

The objective of the study was to compare the morphological findings, quantify the inflammation and renal fibrosis in obese rats submitted to physical exercise. Male Wistar rats were used. Control animals were fed standard feed and tap water, and the obese were fed a hyperlipidic diet. These animals were submitted to intermittent training, where the movement of complete extension of the paw was performed, lifting a load positioned at the back of the vest. The animals' kidneys were collected to evaluate the findings. Regarding the histopathological analysis, no general pathological processes were evidenced. When the fibrosis quantification was performed, no significant results were observed between the groups. It was concluded that no general pathological processes were observed in the kidneys of obese rats and their relationship with physical exercise. In this way, it is suggested to carry out new studies with longer protocols in order to better elucidate the results.   KEYWORDS: Obesity, Kidney, Inflammation, Fibrosis, Exercise.O objetivo do estudo foi comparar os achados morfológicos, quantificar a inflamação e fibrose renal em ratos obesos submetidos ao exercício físico. Foram utilizados 56 ratos machos Wistar. Os animais controles foram alimentados com ração padrão e água de torneira, e os obesos por uma dieta hiperlipídica. Esses animaisforam submetidos ao treinamento intermitente, onde se realizou o movimento de extensão completa da pata, levantando uma carga posicionada na parte posterior do colete. Foram coletados os rins dos animais para avaliar os achados. Com relação à análise histopatológica, não foram evidenciados processos patológicos gerais. Ao ser realizada a quantificação de fibrose, não foram evidenciados resultados significativos entre os grupos. Conclui-se que não foram evidenciados processos patológicos gerais em rins de ratos obesos e sua relação com o exercício físico. Desta forma, é sugerida a realização de novos estudos com protocolos mais longos a fim de elucidar melhor os resultados. Palavras-chaves: Obesidade, rim, Inflamação, fibrose, exercício

Efeito da exposição à fumaça de cigarro durante a prenhez e a lactação de ratas e sua prole sobre parâmetros séricos e morfométricos

PURPOSE: to investigate the effect of cigarette smoke exposure on body and tissue weight gain, serum parameters and milk yield during pregnancy and lactation in rats, and the impact on offspring from birth toil young adulthood. METHODS: 40 Wistar pregnant rats were randomly divided into: CG - not exposed to cigarette smoke and sacrificed at the end of pregnancy; CL - not exposed to cigarette smoke and sacrificed at the end of lactation; FG - exposed to cigarette smoke and sacrificed at the end of pregnancy; FL - exposed to cigarette smoke and sacrificed at the end of lactation. The offspring were separated by gender and divided according to their mothers' groups. Tissue weight, body weight and serum parameters were evaluated in rats and offspring. Milk yield per pup was calculated. RESULTS: body weight was decreased in FL during lactation (CL=267.0±7.2; FL=235.5±7.2 g*, *p<0.05). Adipose tissue was not detected in the CL and FL groups, and was reduced in FG compared to CG (CG=3.3±0.3; FG=2.4±0.3 g*, *p<0.05). Rats exposed to cigarette smoke had higher blood glucose levels (CG=113±17, CL=86±16, FG=177±21*, FL=178±23 mg/dL*, *p<0.05 CG versus FG e CL versus FL), CL and FL groups presented lower HDL-cholesterol with no change in total cholesterol. Finally, rats exposed to cigarette smoke had lower milk yield compared to unexposed rats (CL=6.7±0.4, FL=5.4±0.3 g*, *p<0.05). In offspring from the FG and FL groups, there was a decrease of body weight from birth to young adulthood, with no changes in gastrocnemius, liver or heart weights in any group, and adipose tissue was no detected in female offspring. There was an increase in blood glucose in offspring of both sexes from rats exposed to cigarette smoke (males: Pcg=107±10.5, Pcl=115±8.6, Pfg=148±16.8*, Pfl=172±11.2**; females: Pcg=109±27.2, Pcl=104±9.7, Pfg=134±20.0*, Pfl=126±13.3**; p<0.05 *Pcg versus Pfg and **Pcl versus Pfl). CONCLUSIONS: exposure to cigarette smoke provokes impairment of morphometric and serum parameters during pregnancy and lactation both in mothers and offspring, which is maintained during young adulthood

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

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.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.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Age related obesity-induced shortening of GLUT4 mRNA poly(A) tail length in rat gastrocnemius skeletal muscle

Obese insulin resistant animals and humans have shown reduced GLUT4 gene expression. Yet, in skeletal muscle, discrepancy between mRNA and protein regulation has been frequently observed, suggesting a post-transcriptional modulation. We investigated the GLUT4 expression in adipose tissue and muscle of obese 12-month-old (12-mo) rats, comparing with lean 2-month-old (2-mo) animals. Obesity was accompanied by insulin resistance, and 65% reduction (P < 0.01) in GLUT4 mRNA and protein in adipose tissue. However, in muscle, despite increased (P < 0.05) mRNA content, GLUT4 protein was unchanged. RNase H and poly(A) test assays showed a reduction (P < 0.01) of ∼80 adenines in the GLUT4 mRNA poly(A) tail of muscle from 12-mo rats, recognizing that the poly(A) tail length correlates with translation efficiency. Concluding, age related obesity of 12-mo rats involves suppression of GLUT4 expression in adipose tissue; however, in muscle, GLUT4 mRNA content increases, but with a shorter poly(A) tail, thus unchanging the protein content. © 2007 Elsevier B.V. All rights reserved

Acute and short-term insulin-induced molecular adaptations of GLUT2 gene expression in the renal cortex of diabetic rats

Increased GLUT2 gene expression in the renal proximal tubule of diabetic rats is an adaptive condition, which may be important in the diabetic nephropathy development. We investigated the effects of insulin treatment upon the renal GLUT2 overexpression of diabetic rats. Acute treatment, surprisingly, induced a rapid further increase in GLUT2 mRNA content. Twelve hours after insulin injection, GLUT2 mRNA was twice the value of saline-injected rats (P < 0.001), when GLUT2 protein remained unchanged. In response to short-term treatment, both GLUT2 mRNA and protein were increased in 1-day treated rats (P < 0.05 versus saline-injected), decreasing after that, and reaching, within 6 days, values close to those of non-diabetic rats. Concluding, insulin treatment induced: initially, an additional upregulation of GLUT2 gene expression, involving posttranscriptional modulation; thereafter, downregulation of GLUT2 expression, which returns to non-diabetic levels. The former may be related to increased insulin concentration, the latter may be due to glycemic control. © 2005 Elsevier B.V. All rights reserved

Six-week anaerobic training improves proteolytic profile of diabetic rats

Objective To evaluate the effect of six-week anaerobic training on the mRNA expression of genes related to proteolysis Ubb (Ubiquitin), E2-14kDa, Trim63 (MuRF1 protein) and Nfkb1 in the skeletal muscle of diabetic rats.Materials and methods Four groups were established: DE (DiabetesExercised), DS (Diabetes Sedentary), CE (Control Exercised) and CS (Control Sedentary). The training consisted of 3 sets of 12 jumps in the liquid mean with load equivalent to 50% of BW for 6 weeks. Euthanasia occurred under ip anesthesia, and blood, adipose tissue and skeletal muscles were collected. Gene expression was quantified by RT–PCR in the gastrocnemius muscle. ANOVA one-way was used for comparison among groups, with post-hoc (Tukey) when necessary, considering p < 0.05.Results We observed reduction in the body weight and adipose tissue in the diabetic groups. The muscle mass was reduced in DS, which could be reversed by training (DE). Although DS and DE have presented similar body weight, the training protocol in DE promoted reduction in the adipose tissue, and increase of muscle mass. Anaerobic training was efficient to reduce glycaemia only in the diabetic animals until 6 hours after the end of training. The Trim63 gene expression was increased in DS; decreased Ubb gene level was observed in trained rats (CE and DE) compared to sedentary (CS and DS), and DE presented the lowest level of E2-14kDa gene expression.Conclusion Six-week anaerobic training promoted muscle mass gain, improved glycemic control, and exerted inhibitory effect on the proteolysis of gastrocnemius muscle of diabetic rats