Obesity-like metabolic effects of high-carbohydrate or high-fat diets consumption in metabolic and renal functions.

Present study investigated which diet, high-carbohydrate (HCD) or high-fat (HFD), most effectively induces classical characteristics of obesity in mice. Mice were fed commercial chow (control), an HCD, or an HFD for 12 weeks. HFD and HCD increased body weight, fat mass, and glycaemia, whereas the HFD augmented insulinemia. In the kidney, the HFD caused albuminuria, and reductions in fractional Na+ excretion, Thromboxane B2 (TXB2) excretion, and urinary flow, whereas the HCD reduced glomerular filtration, plasma osmolality, and TXB2 and Prostaglandin E2 excretion. The consumption of HFD and HCD modified parameters that indicate histopathological changes, such as proliferation (proliferating-cell-nuclear antigen), inflammation (c-Jun N-terminal-protein), and epithelial-mesenchymal transition (vimentin, and desmin) in renal tissue, but the HCD group presents fewer signals of glomerular hypertrophy or tubule degeneration. In summary, the HCD generated the metabolic and renal changes required for an obesity model, but with a delay in the development of these modifications concerning the HFD.

Does Oil Rich in Alpha-Linolenic Fatty Acid Cause the Same Immune Modulation as Fish Oil in Walker 256 Tumor-Bearing Rats?

OBJECTIVE: Polyunsaturated fatty acids n-3 (PUFA n-3) have shown effects in reducing tumor growth, in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) abundantly present in fish oil (FO). When these fatty acids are provided in the diet, they alter the functions of the cells, particularly in tumor and immune cells. However, the effects of α-linolenic fatty acid (ALA), which is the precursor of EPA and DHA, are controversial. Thus, our objective was to test the effect of this parental fatty acid. METHODS: Non-tumor-bearing and tumor-bearing Wistar rats (70 days) were supplemented with 1 g/kg body weight of FO or Oro Inca® (OI) oil (rich in ALA). Immune cells function, proliferation, cytokine production, and subpopulation profile were evaluated. RESULTS: We have shown that innate immune cells enhanced phagocytosis capacity, and increased processing and elimination of antigens. Moreover, there was a decrease in production of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6)) by macrophages. Lymphocytes showed decreased proliferation capacity, increased cluster of differentiation 8 (CD8+) subpopulation, and increased TNF-α production. CONCLUSIONS: Oil rich in ALA caused similar immune modulation in cancer when compared with FO.

Fish oil administration mediates apoptosis of Walker 256 tumor cells by modulation of p53, Bcl-2, caspase-7 and caspase-3 protein expression.

BACKGROUND: Several studies have been shown pro-apoptotic effects of fish oil (FO), rich in n-3 polyunsaturated fatty acids (n-3 PUFA) on cancer cells. Nevertheless, few in vivo experiments have provided data of its ability on apoptosis protein expression in tumor tissue. Thus, in this study we investigate the effect of FO supplementation on apoptosis protein expression in Walker 256 tumor bearing rats. Male Wistar rats were randomly assigned to three groups: fed with regular chow (W); fed regular chow supplemented with FO (WFO) or coconut fat (WCO) (1 g/kg body weight/daily). After thirty days, all animals were inoculated subcutaneously with Walker 256 tumor cells. FINDINGS: Protein expression was done by western blotting in Walker 256 tumor tissue samples. FO decreased the Bcl-2/Bax ratio (p < 0.05) and increased the p53 (p < 0.05), cleaved caspase-7 (p < 0.05) and cleaved caspase-3 (p < 0.05) in Walker 256 tumor tissue. CONCLUSIONS: Our data suggest that the pro-apoptotic effect of FO in Walker 256 tumor is related with specifics cleaved caspases.

α-Linolenic Fatty Acid Supplementation Decreases Tumor Growth and Cachexia Parameters in Walker 256 Tumor-Bearing Rats.

Fish oil (FO) has been shown to affect cancer cachexia, tumor mass, and immunity cell. n-3 PUFA, specifically α-linolenic fatty acid (ALA), has controversial effects. We investigated this in nontumor-bearing Wistar rats fed regular chow (C), fed regular chow and supplemented with FO or Oro Inca oil (OI), and Walker 256 tumor-bearing rats fed regular chow (W), fed regular chow and supplemented with FO (WFO) or OI (WOI). Rats were supplemented (1g/kg body weight/day) during 4 wk and then the groups tumor-bearing were inoculated with Walker 256 tumor cells suspension and 14 days later the animals were killed. WFO increased EPA fivefold and DHA 1.5-fold in the tumor tissue compared to W (P < 0.05). OI supplementation increased of threefold of ALA when compared to W (P < 0.05). Tumor mass in WFO and OI was of 2.3-fold lower, as well as tumor cell proliferation of 3.0-fold tumor tissue lipoperoxidation increased of 76.6% and cox-2 expression was 20% lower. Cachexia parameters were attenuate, blood glucose (25% higher), Triacylglycerolemia (50% lower), and plasma TNF-α (65% lower; P < 0.05) and IL-6 (62.5% lower). OI, rich in ALA, caused the same effect on cancer as those seen in FO.

Exercício de força associado a óleo de peixe reduzem massa tumoral e caquexia em ratos / Resistance exercise and fish oil reduce tumor mass and cachexia in rats / Ejercicio de fuerza asociado a aceite de pescado reduce la masa tumoral y la caquexia en ratas

OBJETIVO: Investigar o efeito do treinamento de salto associado à suplementação com óleo de peixe (1g/kg peso corporal/dia) em ratos portadores do tumor de Walker 256, sobre parâmetros bioquímicos de caquexia e crescimento tumoral. MÉTODOS: Oitenta Ratos foram divididos em sedentário sem ou com tumor (S ou SW), exercitado (EX ou EXW), suplementado com óleo de peixe (SO ou SWO) e suplementado e exercitado (EXO ou EXWO). Sessões de treinamento de salto consistiram de 10 séries com duração de 30 segundos e intervalo de 1 minuto entre cada série. Após seis semanas de treinamento, células do tumor de Walker 256 foram inoculadas e após 15 dias os animais foram mortos. RESULTADOS: O peso médio do tumor no grupo SW foi de 25,32 g, p<0,05 vs. ao dos SWO, EXW e EXWO (~11 g). O grupo SW apresentou hipoglicemia, hiperlactatemia, hipertriacilglicerolemia e perda de peso (-7,52±3,19g), caracterizando estado caquético. Suplementação com óleo de peixe (SWO), exercício (EXW) e associação de ambos (EXWO) impediram a instalação da caquexia (p<0,05 vs. SW). No grupo SWO, EXW e suas associações (EXWO) promoveram ganho de peso (p<0,05 vs. SW), mas inferior ao da suplementação isolada (p<0,05 vs. SWO). A proliferação celular in vitro das células tumorais foi menor no grupo SWO (p<0,05 vs. SW) e o exercício reduziu ainda mais (p<0,05 vs. SW e SWO), não havendo incremento quando se associaram ambas as terapias. Lipoperoxidação (p<0,05) foi maior nos SWO, EXW, EXWO vs. S. A expressão de Bcl-2 foi menor também nestes grupos vs. SW. CONCLUSÕES: O treinamento de força e a suplementação com óleo de peixe foram eficazes em evitar a caquexia e induzir a redução do crescimento tumoral, da prolife...

OBJECTIVE: To investigate the effect of jump training associated with fish oil (FO) supplementation (1g/Kg bodyweight/day) on biochemical parameters of cachexia and tumor growth in Walker 256 tumor-bearing rats. METHODS: Eighty rats were divided into sedentary non- and tumor-bearing (S and SW), exercised (EX and EXW), FO supplemented (SO and SWO), and both supplemented and exercised (EXW and EXWO). Jump training sessions consisted of 10 series of 30 seconds each, followed by 1 minute of rest. After six weeks of jump training, ascitic cells from Walker 256 tumor bearing-rat were inoculated, and after 15 days, all the animals were sacrificed. RESULTS: The tumor mass in the SW group was 25.32 g, p<0.05 vs the SWO, EXW and EXWO groups (~11 g). The SW group presented hypoglycemia, hyperlactacidemia and hypertriacylglycerolemia and a reduction in body weight (-7.52 ± 3.19g), characterizing a state of cachexia. Supplementation with fish oil (SWO), exercise (EXW) and both (EXWO) prevented the onset of cachexia and promoted weight gain (p<0.05 vs SW), but less than that of the supplementation alone (p<0.05 vs SWO). In vitro cell proliferation of the tumor cells was lower in the SWO group (p<0.05 vs SW) and exercise reduced still further (p<0.05 vs. SW and SWO), with no increase when both therapies were applied together. Lipoperoxidation (p<0.05) was higher in the SWO, EXW, EXWO groups vs. S. Bcl-2 expression was also lower in these groups vs. SW. CONCLUSIONS: Jump training and fish oil supplementation alone were able to effectively prevent cachexia and reduce tumor growth, tumor cell proliferation, and Bcl-2 expression, but the combination of both did not promote any additive effect. .

OBJETIVO: Investigar el efecto del entrenamiento de salto asociado a suplementación con aceite de pescado (1 g/kg peso corporal/día ) en ratas portadoras del tumor de Walker 256 de acuerdo con los parámetros bioquímicos de la caquexia y el crecimiento tumoral. MÉTODOS: Ochenta ratas fueron divididas en sedentarias sin y con tumor (S o SW), ejercitadas (EX o EXW), suplementadas con aceite de pescado (SO o SWO) y ejercitadas y suplementadas de forma simultánea (EXO o EXWO). Las sesiones de entrenamiento de salto consistieron en 10 series de 30 segundos cada una seguidas por 1 minuto de descanso entre cada serie. Después de seis semanas de entrenamiento, las células del tumor de Walker 256 se inocularon en las ratas y 15 días después todos los animales fueron sacrificados. RESULTADOS: El peso medio del tumor en el grupo SW fue de 25,32 g (p < 0,05) con respecto a los grupos SWO, EXW y EXWO (~11 g). El grupo SW presento hipoglucemia, hiperlactatemia y hipertriacilglicerolemia y reducción de peso corporal (-7,52 ± 3,19 g), lo que caracteriza el estado caquéctico. La suplementación con aceite de pescado (SWO), el ejercicio (EXW) y la asociación de ambos (EXWO) impidieron la instalación de la caquexia (p < 0,05 vs. SW). En el grupo SWO, EXW e sus asociaciones (EXWO) promovieron aumento de peso (p < 0,05 vs. SW), pero inferior al de la suplementación aislada (p < 0,05 vs. SWO). La proliferación in vitro de las células tumorales fue menor en el grupo SWO (p < 0,05 vs. SW) y el ejercicio la redujo todavía más (p < 0,05 vs. SW e SWO), no habiendo incremento cuando se asociaran ambas las terapias. La lipoperoxidación fue mayor en los grupos SWO, EXW, EXWO con respecto al grupo S (p < 0,05). La expresión de Bcl-2 en estos grupos también fue menor que en SW. CONCLUSIONES: El entrenamiento de fuerza ...

Interval training attenuates the metabolic disturbances in type 1 diabetes rat model.

OBJECTIVE: This study investigated the effect of interval training on blood biochemistry and immune parameters in type 1 diabetic rats. MATERIALS AND METHODS: Male Wistar rats were divided into four groups: sedentary (SE, n = 15), interval training (IT, n = 17), diabetic sedentary (DSE, n = 17), diabetic interval training (DIT, n = 17). Diabetes was induced by i.v. injection of streptozotocin (60 mg/kg). Swimming Interval Training consisted of 30-s exercise with 30-s rest, for 30 minutes, during 6 weeks, four times a week, with an overload of 15% of body mass. Plasma glucose, lactate, triacylglycerol and total cholesterol concentrations, phagocytic capacity, cationic vesicle content, and superoxide anion and hydrogen peroxide production by blood neutrophils and peritoneal macrophages were evaluated. Proliferation of mesenteric lymphocytes was also estimated. RESULTS: Interval training resulted in attenuation of the resting hyperglycemic state and decreased blood lipids in the DIT group. Diabetes increased the functionality of blood neutrophils and peritoneal macrophages in the DSE group. Interval training increased all functionality parameters of peritoneal macrophages in the IT group. Interval training also led to a twofold increase in the proliferation of mesenteric lymphocytes after 6 weeks of exercise in the DIT group. CONCLUSION: Low-volume high-intensity physical exercise attenuates hyperglycemia and dislipidemia induced by type 1 diabetes, and induces changes in the functionality of innate and acquired immunity.

Interval training attenuates the metabolic disturbances in type 1 diabetes rat model / Treinamento intervalado atenua os distúrbios metabólicos em modelo de ratos diabéticos do tipo 1

OBJECTIVE: This study investigated the effect of interval training on blood biochemistry and immune parameters in type 1 diabetic rats. MATERIALS AND METHODS: Male Wistar rats were divided into four groups: sedentary (SE, n = 15), interval training (IT, n = 17), diabetic sedentary (DSE, n = 17), diabetic interval training (DIT, n = 17). Diabetes was induced by i.v. injection of streptozotocin (60 mg/kg). Swimming Interval Training consisted of 30-s exercise with 30-s rest, for 30 minutes, during 6 weeks, four times a week, with an overload of 15% of body mass. Plasma glucose, lactate, triacylglycerol and total cholesterol concentrations, phagocytic capacity, cationic vesicle content, and superoxide anion and hydrogen peroxide production by blood neutrophils and peritoneal macrophages were evaluated. Proliferation of mesenteric lymphocytes was also estimated. RESULTS: Interval training resulted in attenuation of the resting hyperglycemic state and decreased blood lipids in the DIT group. Diabetes increased the functionality of blood neutrophils and peritoneal macrophages in the DSE group. Interval training increased all functionality parameters of peritoneal macrophages in the IT group. Interval training also led to a twofold increase in the proliferation of mesenteric lymphocytes after 6 weeks of exercise in the DIT group. CONCLUSION: Low-volume high-intensity physical exercise attenuates hyperglycemia and dislipidemia induced by type 1 diabetes, and induces changes in the functionality of innate and acquired immunity.

OBJETIVO: Este estudo investigou os efeitos do treinamento intervalado sobre parâmetros bioquímicos e imunológicos em ratos diabéticos do tipo 1. MATERIAIS E MÉTODOS: Ratos Wistar machos foram divididos em quatro grupos: sedentário (SE, n = 15), treinamento intervalado (TI, n = 17), sedentário diabético (SED, n = 17) e treinamento intervalado diabético (TID, n = 17). O diabetes foi induzido por uma injeção intravenosa de estreptozotocina (60 mg/kg). O treinamento intervalado de natação consistiu de 30s de exercício com 30s de recuperação, 30 minutos, durante 6 semanas, 4 vezes por semana, com sobrecarga de 15% da massa corporal. Foram avaliados glicemia, lactato sanguíneo, concentração de triacilglicerol e colesterol total, capacidade fagocítica, conteúdo de vesículas catiô­nicas, produção de ânion superóxido e peróxido de hidrogênio por neutrófilos sanguíneos e macrófagos peritoneais. A proliferação de linfócitos mesentéricos também foi avaliada. RESULTADOS: O treinamento intervalado resultou em atenuação do estado hiperglicêmico e diminuiu os lipídeos sanguíneos no grupo TID. O diabetes aumentou a funcionalidade dos neutrófilos sanguíneos e macrófagos peritoneais do grupo SED. O treinamento intervalado aumentou todos os parâmetros funcionais dos macrófagos peritoneais do grupo TI. O treinamento intervalado também aumentou duas vezes a proliferação dos linfócitos mesentéricos após seis semanas de exercício do grupo TID. CONCLUSÃO: O treinamento intervalado atenua a hiperglicemia e a dislipidemia induzida pelo diabetes do tipo 1 e induz mudanças na funcionalidade da imunidade inata e adquirida.

Fish oil supplementation reduces cachexia and tumor growth while improving renal function in tumor-bearing rats.

The objective of the present work was to study the renal function of healthy and tumor-bearing rats chronically supplemented with fish oil (FO), a source of n-3 polyunsaturated fatty acids. Weanling male rats were divided in two groups, one control (C) and another orally supplemented for 70 days with FO (1 g/kg body weight). After this time, half the animals of each group were injected in the right flank with a suspension of Walker 256 tumor cells (W and WFO). The W group had less proteinemia reflecting cachectic proteolysis, FO reversed this fact. Tumor weight gain was also reduced in WFO. Glomerular filtration rate (GFR) was not different in FO or W compared to C, but was higher in WFO. Renal plasma flow (RPF) was higher in the FO supplemented groups. The W group had lower plasma osmolality than the C group, but FO supplementation resulted in normalization of this parameter. Fractional sodium excretion (FE(Na+)) of FO rats was similar to C. Proximal Na(+) reabsorption, evaluated by lithium clearance, was similar among the groups. Urinary thromboxane B(2) (TXB(2)) excretion was lower in the supplemented groups. The number of macrophages in renal tissue was higher in W compared to C rats, but was lower in WFO rats compared to W rats. In conclusion, FO supplementation resulted in less tumor growth and cachexia, and appeared to be renoprotective, as suggested by higher RPF and GFR.

Low fish oil intake improves insulin sensitivity, lipid profile and muscle metabolism on insulin resistant MSG-obese rats.

BACKGROUND: Obesity is commonly associated with diabetes, cardiovascular diseases and cancer. The purpose of this study was to determinate the effect of a lower dose of fish oil supplementation on insulin sensitivity, lipid profile, and muscle metabolism in obese rats. METHODS: Monosodium glutamate (MSG) (4 mg/g body weight) was injected in neonatal Wistar male rats. Three-month-old rats were divided in normal-weight control group (C), coconut fat-treated normal weight group (CO), fish oil-treated normal weight group (FO), obese control group (Ob), coconut fat-treated obese group (ObCO) and fish oil-treated obese group (ObFO). Obese insulin-resistant rats were supplemented with fish oil or coconut fat (1 g/kg/day) for 4 weeks. Insulin sensitivity, fasting blood biochemicals parameters, and skeletal muscle glucose metabolism were analyzed. RESULTS: Obese animals (Ob) presented higher Index Lee and 2.5 fold epididymal and retroperitoneal adipose tissue than C. Insulin sensitivity test (Kitt) showed that fish oil supplementation was able to maintain insulin sensitivity of obese rats (ObFO) similar to C. There were no changes in glucose and HDL-cholesterol levels amongst groups. Yet, ObFO revealed lower levels of total cholesterol (TC; 30%) and triacylglycerol (TG; 33%) compared to Ob. Finally, since exposed to insulin, ObFO skeletal muscle revealed an increase of 10% in lactate production, 38% in glycogen synthesis and 39% in oxidation of glucose compared to Ob. CONCLUSIONS: Low dose of fish oil supplementation (1 g/kg/day) was able to reduce TC and TG levels, in addition to improved systemic and muscle insulin sensitivity. These results lend credence to the benefits of n-3 fatty acids upon the deleterious effects of insulin resistance mechanisms.