Early introduction of exercise prevents insulin resistance in postnatal overfed rats

Early childhood obesity increases the risk of developing metabolic diseases. We examined the early introduction of exercise in small-litter obese-induced rats (SL) on glucose metabolism in the epididymal adipose tissue (AT) and soleus muscle (SM). On day 3 post-birth, pups were divided into groups of ten or three (SL). On day 22, rats were split into sedentary (S and SLS) and exercise (E and SLE) groups. The rats swam three times/week carrying a load for 30 min. In the first week, they swam without a load; in the 2nd week, they carried a load equivalent to 2% of their body weight; from the 3rd week to the final week, they carried a 5% body load. At 85 days of age, an insulin tolerance test was performed in some rats. At 90 days of age, rats were killed, and blood was harvested for plasma glucose, cholesterol, and triacylglycerol measurements. Mesenteric, epididymal, retroperitoneal, and brown adipose tissues were removed and weighed. SM and AT were incubated in the Krebs-Ringer bicarbonate buffer, 5.5 mM glucose for 1 h with or without 10 mU/mL insulin. Comparison between the groups was performed by 3-way ANOVA followed by the Tukey post-hoc test. Sedentary, overfed rats had greater body mass, more visceral fat, lower lactate production, and insulin resistance. Early introduction of exercise reduced plasma cholesterol and contained the deposition of white adipose tissue and insulin resistance. In conclusion, the early introduction of exercise prevents the effects of obesity on glucose metabolism in adulthood in this rat model.

Tumor growth reduction is regulated at the gene level in Walker 256 tumor-bearing rats supplemented with fish oil rich in EPA and DHA

We investigated the effect of fish oil (FO) supplementation on tumor growth, cyclooxygenase 2 (COX-2), peroxisome proliferator-activated receptor gamma (PPARγ), and RelA gene and protein expression in Walker 256 tumor-bearing rats. Male Wistar rats (70 days old) were fed with regular chow (group W) or chow supplemented with 1 g/kg body weight FO daily (group WFO) until they reached 100 days of age. Both groups were then inoculated with a suspension of Walker 256 ascitic tumor cells (3×107 cells/mL). After 14 days the rats were killed, total RNA was isolated from the tumor tissue, and relative mRNA expression was measured using the 2-ΔΔCT method. FO significantly decreased tumor growth (W=13.18±1.58 vs WFO=5.40±0.88 g, P<0.05). FO supplementation also resulted in a significant decrease in COX-2 (W=100.1±1.62 vs WFO=59.39±5.53, P<0.001) and PPARγ (W=100.4±1.04 vs WFO=88.22±1.46, P<0.05) protein expression. Relative mRNA expression was W=1.06±0.022 vs WFO=0.31±0.04 (P<0.001) for COX-2, W=1.08±0.02 vs WFO=0.52±0.08 (P<0.001) for PPARγ, and W=1.04±0.02 vs WFO=0.82±0.04 (P<0.05) for RelA. FO reduced tumor growth by attenuating inflammatory gene expression associated with carcinogenesis.

Time motion analysis of football (soccer) referees during official matches in relation to the type of fluid consumed

The aim of the present study was to determine the effect of volume and composition of fluid replacement on the physical performance of male football referees. Ten referees were evaluated during three official matches. In one match the participants were asked to consume mineral water ad libitum, and in the others they consumed a pre-determined volume of mineral water or a carbohydrate electrolyte solution (6.4 percent carbohydrate and 22 mM Na+) equivalent to 1 percent of their baseline body mass (half before the match and half during the interval). Total water loss, sweat rate and match physiological performance were measured. When rehydrated ad libitum (pre-match and at half time) participants lost 1.97 ± 0.18 percent of their pre-match body mass (2.14 ± 0.19 L). This parameter was significantly reduced when they consumed a pre-determined volume of fluid. Sweat rate was significantly reduced when the referees ingested a pre-determined volume of a carbohydrate electrolyte solution, 0.72 ± 0.12 vs 1.16 ± 0.11 L/h ad libitum. The high percentage (74.1 percent) of movements at low speed (walking, jogging) observed when they ingested fluid ad libitum was significantly reduced to 71 percent with mineral water and to 69.9 percent with carbohydrate solution. An increase in percent movement expended in backward running was observed when they consumed a pre-determined volume of carbohydrate solution, 7.7 ± 0.5 vs 5.5 ± 0.5 percent ad libitum. The improved hydration status achieved with the carbohydrate electrolyte solution reduced the length of time spent in activities at low-speed movements and increased the time spent in activities demanding high-energy expenditure.

Modulation of peritoneal macrophage activity by the saturation state of the fatty acid moiety of phosphatidylcholine

To determine the effects of saturated and unsaturated fatty acids in phosphatidylcholine (PC) on macrophage activity, peritoneal lavage cells were cultured in the presence of phosphatidylcholine rich in saturated or unsaturated fatty acids (sat PC and unsatPC, respectively), both used at concentrations of 32 and 64 ìM. The treatment of peritoneal macrophages with 64 ìM unsat PC increased the production of hydrogen peroxide by 48.3% compared to control (148.3 ± 16.3 vs 100.0 ± 1.8%, N = 15), and both doses of unsat PC increased adhesion capacity by nearly 50%. Moreover, 64 ìM unsat PC decreased neutral red uptake by lysosomes by 32.5% compared to the untreated group (67.5 ± 6.8 vs 100.0 ± 5.5%, N = 15), while both 32 and 64 ìM unsat PC decreased the production of lipopolysaccharide-elicited nitric oxide by 30.4% (13.5 ± 2.6 vs 19.4 ± 2.5 ìM) and 46.4% (10.4 ± 3.1 vs 19.4 ± 2.5 ìM), respectively. Unsat PC did not affect anion production in non-stimulated cells or phagocytosis of unopsonized zymosan particles. A different result pattern was obtained for macrophages treated with sat PC. Phorbol 12-miristate 13-acetate-elicited superoxide production and neutral red uptake were decreased by nearly 25% by 32 and 64 ìM sat PC, respectively. Sat PC did not affect nitric oxide or hydrogen peroxide production, adhesion capacity or zymosan phagocytosis. Thus, PC modifies macrophage activity, but this effect depends on cell activation state, fatty acid saturation and esterification to PC molecule and PC concentration. Taken together, these results indicate that the fatty acid moiety of PC modulates macrophage activity and, consequently, is likely to affect immune system regulation in vivo.

Effect of chronic fish oil supplementation on renal function of normal and cachectic rats

In the present study we determined the effect of chronic diet supplementation with n-3 PUFA on renal function of healthy and cachectic subjects by providing fish oil (1 g/kg body weight) to female rats throughout pregnancy and lactation and then to their offspring post-weaning and examined its effect on renal function parameters during their adulthood. The animals were divided into four groups of 5-10 rats in each group: control, control supplemented with fish oil (P), cachectic Walker 256 tumor-bearing (W), and W supplemented with fish oil (WP). Food intake was significantly lower in the W group compared to control (12.66 ± 4.24 vs 25.30 ± 1.07 g/day). Treatment with fish oil significantly reversed this reduction (22.70 ± 2.94 g/day). Tumor growth rate was markedly reduced in the P group (16.41 ± 2.09 for WP vs 24.06 ± 2.64 g for W). WP group showed a significant increase in mean glomerular filtration rate compared to P and control (1.520 ± 0.214 ml min-1 kg body weight-1; P < 0.05). Tumor-bearing groups had low urine osmolality compared to control rats. The fractional sodium excretion decreased in the W group compared to control (0.43 ± 0.16 vs 2.99 ± 0.87 percent; P < 0.05), and partially recovered in the WP group (0.90 ± 0.20 percent). In summary, the chronic supplementation with fish oil used in this study increased the amount of fat in the diet by only 0.1 percent, but caused remarkable changes in tumor growth rate and cachexia, also showing a renoprotective function.

Estudo comparativo entre anastomoses intestinais com sutura manual e com anel biofragmentável em cäes sob a administraçäo de corticosteróides / Comparative study between intestinal anastomosis with manual suture and biofragmentable ring in dogs under corticosteroid administration

OBJETIVO: Este estudo analisou anastomoses intestinais por sutura manual e por compressão com anel biofragmentável, sob retardo cicatricial pela administração parenteral de corticosteróides. MATERIAL E MÉTODOS: Vinte cães, entre 15 e 20 kg, foram divididos em grupos controle e teste, este submetido à administração intramuscular de hemissuccinato de hidrocortisona, de 25 a 33 mg/kg/dia, do 30§ dia pré-operatório ao 7§ dia pós-operatório. Em ato cirúrgico, cada animal foi submetido a duas secções cólicas, com anastomoses por sutura manual em plano único extramucoso e por compressão com anel biofragmentável. Os espécimes foram sacrificados sete dias após o procedimento para avaliação das anastomoses. RESULTADOS: No pós-operatório ocorreram um óbito no grupo teste e dois óbitos no grupo controle por fístula não bloqueada nas anastomoses por compressão com anel. Houve, estatisticamente, incidência semelhante de aderências, fístulas, dilatação aferente e obstrução, nos métodos em comparação. À microscopia, houve deficiência de regeneração mucosa nas anastomoses por compressão. Análise histológica por computador evidenciou nas anastomoses por compressão, maior reação inflamatória, maior edema de submucosa e formação de cicatrizes alargadas. CONCLUSÕES: Com o anel biofragmentável, em anastomoses colocólicas sob retardo de cicatrização induzido por corticosteróides, foram obtidos resultados semelhantes aos da sutura manual quanto à incidência de complicações pós-operatórias; o anel, entretanto, determinou pior regeneração mucosa e maior reação inflamatória cicatricial.

Insulin and prostaglandins as signals between tumor and the host immune system

The development of malignant tissue in vivo is partially favored by the immunosuppression that occurs in cancer patients. However, the signals between tumor and immune tissues remain to be identified. We present evidence that prostaglandins may act as one of these signals by a direct action on cells of the immune system, or by inhibition of insulin secretion which in turn suppresses immune function, or both

Metabolism of glucose, glutamine and pyruvate in lymphocytes from Walker 256 tumor bearing rats

This study examined the effect of Walker 256 tumor growth in vivo on the metabolism of glucose, glutamine and pyruvate in lymphocytes. A comparison between the metabolism of Walker 256 tumor cells obtained in vivo with that of lymphocytes was also carried out. Lymphocytes and tumor cells were isolated and incubated for 1 h for the following measurements: lactate production from glucose (5.6 mM) and pyruvate (3 mM), glutamate and aspartate formation from glutamine (3 mM) and decarboxylation of [U-14C]-glucose, [U-14C]-glutamine, [1-14C]-pyruvate and [3-14C]-pyruvate. The presence of the tumor increased lactate production (2.7-fold from glucose and 2-fold from pyruvate), decarboxylation of [U-14C]-glucose (3.7-fold) and [1-14C]-pyruvate (4.4-fold) and the formation of aspartate (6.3-fold) and glutamate (4.6-fold) from glutamine. The conversion of glucose to lactate and CO2 was higher in tumor cells as compared to lymphocytes. Tumor cells also showed a higher production of glutamate and an 8-fold increased decarboxylation rate of [U-14C]-glutamine in tumor cells, which was more active than that of lymphocytes even from tumor-bearing rats. Tumor growth stimulated glucose and glutamine metabolism in lymphocytes; however, the importance of this fact for the function of these cells remains to be elucidated

Testes sorológicos para pesquisa de anticorpos em soros de camundongos tratados pelo Trypanosominum TC D30 / Serum test methods for research of antibodies in serum of mice treated by Trypanosominum TC D30

Propomos para o presente trabalho a realizaçäo das reaçöes sorológicas: de fixaçäo do complemento, imunofluorescência indireta e hemaglutinaçäo, onde foram testados soros de camundongos tratados com Trypanosominum TC D30, na pesquisa de imunoglobulinas circulantes, eventualmente existentes no sangue desses animais. Como controle, foram utilizados soros de animais normais associados a soluçäo fisiológica, em substituiçäo ao antígeno, seguindo-se o mesmo esquema usado no tratamento

Composiçäo de leite de éguas de P.S.I e desenvolvimento ponderal de suas crias / Milk composition of the hroroughbred mares and weight gain of the foals

Com o objetivo de analisar a composiçäo do leite, foram coletadas amostras de nove éguas da raça Puro Sangue Inglês. A composiçäo foi determinada em amostras antes da primeira mamada de cada um dos dias considerados. A matéria seca foi determinada por gramivetria, a proteína bruta pelo micro-Kjedahl, a gordura, pelo milko-Tester, a lactose e o fósforo por colorimetria e o cálcio por permanganometria. Os constituintes, com exceçäo da lactose, decresceram durante o período. Os potros atingiram o desenvolvimento ponderal esperado, com um ganho de peso de 1,14 kg/dia durante o periodo observado