Extract of the Bark of Bathysa cuspidataAttenuates the Development of Chemically-Induced Preneoplastic Colorectal Lesions in Rats

ABSTRACTThe aim of this study was to investigate the effect of the bark extractBathysa cuspidata on chemically induced preneoplastic colorectal lesions in Wistar rats. Forty male rats were randomly divided into four groups (n = 10 each): saline (control group, oral administration of saline solution 0.9%); dimethylsulfoxide (DMSO, vehicle control), B200 (treated with 200 mg/kg bark extract ofB. cuspidata), and B400 (treated with 400 mg/kg bark extract ofB. cuspidata). Administration of treatments was carried out by the gavage. The animals received four subcutaneous injections of 1,2-dimethylhydrazine (DMH, 40 mg/kg) in the initial two weeks of the experiment to induce preneoplastic colorectal lesions. After 15 weeks, the animals were euthanized and the presence of aberrant crypt foci (ACF), body weight, biochemical analyses, and oxidative stress markers were measured. The extract ofB. cuspidata decreased the levels of superoxide dismutase (SOD), but did not influence the levels of catalase (CAT), malondialdehyde (MDA), nitric oxide or protein carbonyl, compared with the saline group. The animals supplemented with a more concentratedB. cuspidata extract (B400) showed a significant reduction in the number of ACF in all the portions of the intestinal mucosa. The study demonstrated that the bark extract ofB. cuspidata at 400 mg/kg reduced the preneoplastic colorectal lesions in an animal model of colon cancer and that the effect could be dose-dependent.

Use of defatted flaxseed meal reduces precancerous colon lesions in C57BL/6 mice

PURPOSE: To investigate the hemopreventive effect of defatted flaxseed meal in C57BL/6 mice after induction of precancerous colon lesions with 1.2-dimethylhydrazine (DMH). METHODS: Thirty-six 12-week-old C57BL/6 mice were divided into three treatment groups(n=12 in each group): (1) diet with 10% defatted flaxseed meal; (2) diet with defatted flaxseed meal and precancerous colon lesions induced by DMH; and (3) precancerous colon lesions induced by DMH, without defatted flaxseed meal. The incidence of aberrant crypt foci (ACF), oxidative processes, expression of tumor suppressor proteins and cyclins, as well as the profile of short-chain fatty acids (SCFA) in animal feces were investigated in the presence and absence of DMH. RESULTS: The rats consuming defatted flaxseed meals showed lesions with lower multiplicity and a reduced incidence of lesions. No changes in the expression of tumor suppressor proteins and those involved in cell cycle control were detected. CONCLUSION: Defatted flaxseed meal protected the distal colon of mice from precancerous lesions.

Sodium butyrate does not decrease the evolution of precancerous lesions in rats / Butirato de sódio não diminui a evolução de lesões pré-neoplásicas em ratos

PURPOSE: To evaluate the preventive effect of sodium butyrate in the appearance of aberrant crypt foci (ACF) in rats after induction with the carcinogen 1,2-dimethylhydrazine (DMH). METHODS: Forty Wistar rats were separated into four groups (n=10) distributed as follows: control 1, control 2, butyrate 1 and butyrate 2. The groups control 1 and butyrate 1 remained under experimentation for 4 weeks, while the groups control 2 and butyrate 2 remained for 8 weeks. In the first four weeks, the animals of the control groups received water ad libitum and the animals of the butyrate groups received a sodium butyrate solution (3.4 percent) ad libitum. Injections of the drug 1,2-dimethylhydrazine were applied during the two first weeks of the experiment in all the animals, concurrently with the application of sodium butyrate. The large intestine of the animals was removed, for the analysis of the ACF and of the content of polyamines. The animal feces were collected for the analysis of the SCFA profile. RESULTS: The spermidine presented a higher concentration in the group butyrate 2 in comparison to the group control 2. There was a significant difference in the concentration value (µmol/mL) of acetate in comparison to the groups control 2 and butyrate 2. CONCLUSION: The use of sodium butyrate together with the induction of colorectal cancer was not effective in the prevention of the disease progression.

OBJETIVO: Avaliar o efeito preventivo do butirato de sódio no surgimento de focos de cripta aberrante (FCA) em ratos após a indução com o carcinógeno 1,2-dimetilhidrazina. MÉTODOS: Quarenta ratos foram divididos em quatro grupos, com dez animais em cada. Os grupos controle 1 e butirato 1 ficaram em experimentação por 4 semanas e os grupos controle 2 e butirato 2 por oito semanas. Nas primeiras quatro semanas, os animais dos grupos controle receberam água ad libitum e os animais dos grupos butirato receberam solução de butirato de sódio (3,4 por cento) ad libitum. Em todos os animais foram aplicadas quatro injeções subcutâneas da droga 1,2-dimetilhidrazina nas duas primeiras semanas, concomitante a administração do butirato de sódio. Foi retirado o intestino grosso dos animais, para análise dos FCA e do teor de poliaminas. As fezes dos animais foram recolhidas para análise do perfil de AGCC. RESULTADOS: A espermidina apresentou maior concentração no grupo butirato 2 em relação ao grupo controle 2. Foi encontrada diferença significativa no valor da concentração de acetato quando comparado os grupos controle 2 e butirato 2. CONCLUSÃO: A utilização do butirato de sódio concomitante à indução do câncer colorretal não se mostrou efetiva na prevenção da progressão da doença.

Flaxseed, olive and fish oil influence plasmatic lipids, lymphocyte migration and morphometry of the intestinal of Wistar rats / Óleo de linhaça, oliva e peixe influenciam os lipídios plasmáticos, migração de linfócitos e morfometria intestinal de ratos Wistar

PURPOSE: Evaluate the effect of flaxseed, olive and fish oil on the lipid profile, preservation of villosities and lymphocyte migration in the intestinal mucosa of Wistar rats. METHODS: Thirty Wistar male rats were divided into four groups, which received the AIN-93M diet, with changes only to their lipid source: flaxseed, olive, fish, and soy oil (control group). The serum was separated for the biochemical parameter analysis. A histological evaluation was performed in the ileal portion. RESULTS: The group which was fed fish oil presented lower values when compared to the other treatments for Total Cholesterol, High-density Lipoprotein Cholesterol and Triacylglycerol (p<0.05). The animals treated with fish and olive oils presented better intestinal villosities preservation. Less deposition of lymphocytes was observed in the flaxseed group (p<0.001). CONCLUSIONS: This study demonstrated that flaxseed, olive and fish oils present different responses than soy oil for the intestinal mucosa preservation and lymphocyte proliferation in Wistar rats.

OBJETIVO: Avaliar o efeito dos óleos de linhaça, oliva e peixe no perfil lipídico, preservação das vilosidades e migração de linfócitos na mucosa intestinal de ratos Wistar. MÉTODOS: Trinta ratos Wistar foram divididos em quarto grupos e receberam dieta AIN-93M, modificando para cada grupo apenas a fonte lipídica: óleo de linhaça, oliva, peixe e soja ( grupo controle). O soro foi separado para análise dos parâmetros bioquímicos. A análise histológica foi realizada na porção ileal. RESULTADOS: O grupo que recebeu óleo de peixe apresentou menores valores de colesterol total, lipoproteína de alta densidade e triacilglicerol (p<0.05). Os animais tratados com óleo de peixe e oliva apresentaram melhor preservação das vilosidades intestinais. Menor deposição de linfócitos foi observado no grupo tratado com óleo de linhaça (p<0.001). CONCLUSÃO: Este estudo demonstrou que os óleos de linhaça, oliva e peixe apresentam diferentes respostas em relação ao óleo de soja na preservação da mucosa intestinal e proliferação de linfócitos em ratos Wistar.

Hábito alimentar, níveis de lipídios sangüíneos e o status antioxidante de adultos jovens fumantes e não fumantes / Food habits, blood lipid levels and antioxidant status of young adults smokers and non-smokers

OBJETIVO: Avaliar o hábito alimentar, os níveis dos lipídios sangüíneos e o status antioxidante de jovens fumantes e não fumantes. MÉTODOS: Trata-se de um estudo transversal em que 68 indivíduos, de 18 a 26 anos, emparelhados por sexo e idade, foram divididos em dois grupos: fumantes (n=34) e não fumantes (n=34). Os voluntários selecionados em instituições de ensino, em Viçosa (MG) foram questionados quanto a: hábito de fumar, consumo de bebidas alcoólicas e atividade física; também foi estimada a dependência nicotínica. O hábito alimentar foi avaliado por questionário de freqüência de consumo. Quantificaram-se níveis séricos de lipídios, nível plasmático de malondialdeído, vitamina E e vitamina C. RESULTADOS: Os jovens começaram a fumar precocemente, independentemente do sexo. O hábito de fumar foi estratificado e encontrou-se 58,8 por cento de fumantes leves e 41,2 por cento de fumantes pesados. Os fumantes apresentaram hábitos alimentares inadequados e consumo freqüente de bebida alcoólica. De acordo com a recomendação do International Physical Activity Questionnaire 69 por cento dos fumantes eram ativos e 27,6 por cento eram muito ativos. Não se observou diferença significante na concentração sérica de lipídios entre fumantes e não fumantes. No grupo de fumantes mulheres, verificou-se correlação positiva entre o número de cigarros fumados por dia e os triglicerídeos séricos (r=0,824 e p=0,0001) e também entre o tempo que fumavam em anos e o nível de colesterol total (r=0,523 e p=0,031). Os fumantes apresentaram concentração inferior de vitaminas E e C (p=0,002 e p=<0,001, respectivamente) e a concentração de malondialdeído plasmático correlacionou-se ao tempo de tabagismo em anos (r=0,352 e p=0,041). CONCLUSÃO: O grupo de fumantes apresentou hábito alimentar inadequado, principalmente para alimentos gordurosos, e consumo freqüente de bebida alcoólica. Os valores para malondialdeído plasmático apresentaram correlação positiva com o...

OBJECTIVE: The objective was to evaluate the food habits, blood lipid levels and antioxidant status of young adult smokers and non smokers. METHODS: This cross-sectional study divided 68 individuals aged 18 to 26 years, matched for age and sex, into two groups: smokers (n=34) and non-smokers (n=34). The individuals, selected from schools in Viçosa (MG), were asked about smoking status, consumption of alcoholic beverages and physical activity levels. Nicotine dependence was also estimated. The Food Frequency Questionnaire was used to assess food habits. Serum levels of lipids, malondialdehyde, vitamin E and vitamin C were measured. RESULTS: The smokers started smoking early, regardless of sex. The smokers were further stratified into two groups: light smokers (58.8 percent) and heavy smokers (41.2 percent). Smokers had inadequate food habits and consumed alcoholic beverages frequently. According to the International Physical Activity Questionnaire, 69 percent of the smokers were active and 27.6 percent were very active. There was no significant difference between the serum lipid levels of smokers and non-smokers. In women, there was a positive correlation between the number of cigarettes smoked per day and serum triglyceride levels (r=0.824, p=0.0001) and number of years smoking and total cholesterol levels (r=0.523, p=0.031). Smokers had lower vitamin E and C serum concentrations (p=0.002 and p<0.001, respectively) and the concentration of plasma malondialdehyde correlated with the number of years smoking (r=0.352 and p=0.041). CONCLUSION: The group of smokers presented inadequate food habits, consuming alcoholic beverages frequently and high-fat foods. Plasma malondialdehyde levels were positively correlated with the number of years smoking but not with the number of cigarettes smoked per day.