Effect of diets with different protein levels on the growth of Walker 256 carcinosarcoma in rats.

1. The effect of different nutritional situations on the growth of experimental Walker 256 carcinosarcoma was investigated in rats. Fifty adult male Wistar rats were randomly assigned to three groups: group NN received standard chow throughout the experiment; group DD initially received an isocaloric protein-free diet, and some of the animals in this group (DN) were fed normal chow from the 37th to the 53rd day of the study. 2. On the 42nd day of the experiments all animals were inoculated subcutaneously in the flank with 2.5 to 3.0 x 10(5) viable Walker 256 carcinosarcoma cells and tumor growth and rat body weight were monitored daily thereafter. 3. Significantly greater tumor growth was detected in well-nourished (group NNT) as compared with malnourished animals (group DDT), but not in protein-depleted-refed (group DNT) animals, whose tumor growth was not significantly different from that of constantly malnourished (group DDT) rats. 4. Comparison of tumor weight and of the tumor weight/carcass weight (TW/CW) ratio showed no significant difference between malnourished and malnourished/refed animals, whereas well-nourished animals showed higher tumor weight and TW/CW ratios. 5. TW/CW curves for malnourished rats were parallel to those for malnourished/refed rats. TW/CW curves for constantly malnourished rats differed from those for well-nourished rats during the first observation period but there was no difference during the second week of tumor growth. 6. Although the protein-free diet inhibited tumor growth and refeeding enhanced it, carcass weight increased at the same rate, and therefore no change was observed in the TW/CW ratio.(ABSTRACT TRUNCATED AT 250 WORDS)

[Body composition changes in cancer: an experimental study]. / Alterações da composição corpórea no câncer: estudo experimental.

With the aim to study body composition changes in tumor bearing rats submitted to different nutritional conditions, Wistar rats were separated in three diet groups: regular chow, aproteic diet and regular chow after three weeks of aproteic diet. Afterwards the animals were divided in two subgroups: Waler 256 carcinossarcoma bearing rats and tumor free controls. After the sacrifice body composition measurements by the carcass analysis method were performed. Tumor bearing rats presented significant waste of total body fat, body cell mass and increase of Na/K ratio without relation to the nutritional regimen. From this data we conclude that Walker 256 carcinosarcoma causes protein caloric malnutrition even in already depleted rats. After adequate refeeding, body composition rebuilding was obtained in tumor bearing malnourished rats.

[Effects of protein malnutrition on the metabolic response to trauma]. / Efeitos da desnutrição protéica sobre a resposta metabólica ao trauma.

An experimental study was carried out in rats with the purpose to evaluate post-traumatic metabolic changes in the animals submitted to proteic malnutrition. Rats fed with diets with different contents were submitted to a standardized osteomuscular trauma and had nitrogen balance and body composition parameters analysed. After 21 days of feeding with normoproteic diet chow (N) or hypoproteic diet (D) all the animals were submitted to a dorsal skin wound (subgroups NJ (6) and DJ (6). Besides the skin wound part of the rats suffered also the osteomuscular trauma (subgroups NF (6) and DF (6). After 14 days of osteomuscular trauma all the rats were sacrificed and the carcasses were prepared for body composition measurements. Body weight, food intake, fecal and urinary total nitrogen were measured daily. It was observed that in rats with normoproteic diet the osteomuscular trauma promoted a decrease of food intake and loss of weight; in animals on hipoproteic diet it was observed an increase in total urinary nitrogen output and reduction of nitrogen balance. However, there was no reduction of food intake, loss of body weight and changes in composition of body compartments.

[Influences of antitumoral chemotherapy on body composition and nitrogen balance: experimental study]. / Conseqüências da quimioterapia antitumoral sobre a composição corpórea e o balanço nitrogenado: estudo experimental.

An experimental study was carried out with the purpose to examine the 4-epidoxorubicine (4-EPI) action on malignant tumor development and its repercussion on nutritional conditions of the host. Cancer and chemotherapy can generate malnutrition. In order to study the nutritional repercussions, 48 host Wistar rats were divided into 5 groups: Group C: 12 control rats; Group T: 5 rats bearing Walker-256 carcinosarcoma; Group TE: 11 rats given 4-epidoxorubicine (4-EPI) EV simultaneously with tumor implantation; Group T6E: 8 rats given 4-EPI 6 days after the tumor implantation; Group E: 11 rats given only 4-EPI. Tumor and carcass weight and nitrogen balance (by measuring total nitrogen ingested and excreted) were determined daily; the animals were sacrificed on the 20th day of the experiment and material was collected for determination of body composition parameters. A variance analysis was made and the differences were considered to be significative at p less than 0.05. A loss of food during a period following the 4-EPI injection was reflected by carcass weight loss. The accumulated nitrogen incorporation was lower in Groups TE and T6E in the periods of 0-5 days, 0-14 days, and 0-20 days. As for body composition it was verified that free fat solids and total body fat were reduced in Groups T ant T6E when compared to group C. However, 20 days after the use of 4-EPI there were no significative changes in the body composition. In rats bearing Walker-256-carcinosarcoma 4-EPI was effective.(ABSTRACT TRUNCATED AT 250 WORDS)

4-Epidoxorubicin activity in experimental malignant tumors

A literatura tem indicado a atividade positiva da doxorrubicina sobre adenocarcinomas gastrointestinais, seja isoladamente, seja em associacao com outros quimioterapicos. Permanece, porem, a critica representada pela toxicidade da droga, o que tem levado a pesquisa de derivados mais toleraveis e igualmente atuantes; e o caso da 4-epidoxorrubicina (4-EPI). E estudada a atividade da 4-EPI sobre o tumor maligno experimental denominado carcinossarcoma de Walker 256. Para tanto, foi observado o comportamento de 48 ratos Wistar adultos dividos aleatoriamente em cinco grupos: grupo T (seis ratos), com animais que receberam implante subcutaneo de celulas do tumor de Walker na regiao do flanco; grupo TE (11 ratos), em que os animais recebiam o implante tumoral, tal como descrito e simultaneamente a injecao endovenosa de 1 mg de 4-EPI na veia caudal; grupo T6E (oito ratos), em que os animais recebiam a 4-EPI, na dose referida, 6 dias apos o implante tumoral; grupo E (11 ratos) apenas injetados com a 4-EPI, sempre por via endovenosa; grupo C (12 ratos), que servia de controle para o comportamento dos demais grupos. Os animais de todos os grupos eram mantidos em gaiolas metabolicas individuais, recebendo dieta padronizada. Diariamente eram registrados: quantidade de dieta ingerida; peso corporeo;...