In vivo antitumor activity of Euphorbia lathyris ethanol extract in colon cancer models.

Euphorbia lathyris seeds have been used to treat various medical conditions. We previously reported that ethanolic extract from the defatted seed of Euphorbia lathyris (EE) (variety S3201) possesses a potent in vitro antitumor activity against colon cancer (CRC) cell lines. However, the effects of EE on CRC in vivo models and its possible preventive activity have not been elucidated. The aim of this study is to develop an in vivo study to corroborate its efficacy. For this purpose, two tumor induction models have been developed. In orthotopic xenograft model, it has been shown that EE reduces tumor size without hematological toxicity. The ethanolic extract induced an intense apoptosis in tumors mediated by caspase 3. Using the Azoxymethane/Dextran Sulfate Sodium model, a reduction of dysplastic polyps has been demonstrated, showing its preventive power. Furthermore, EE promoted the presence of an eubiotic microbiotal environment in the mucosa of the colon and induced an increase in antioxidant enzyme activity. This fact was accompanied by a modulation of cytokine expression that could be related to its protective mechanism. Therefore, although further experiments will be necessary to determine its applicability in the treatment of CRC, ES could be a new prevention strategy as well as treatment for this type of tumor, being a powerful candidate for future clinical trials.

Efectos de la intervención nutricional y de otros hábitos de vida en el metabolismo lipídico de pacientes con patología vascular, periférica (fontaine grado ii) / Effetcs of nutritional intervention and lifestyles on lipid metabolism of patients with peripheal vascular disease

La enfermedad vascular periférica (EVP) se caracteriza por arteriosclerosis e isquemia de extremidades inferiores que originan la claudicación intermitente. Los pacientes agrupados en el grado 11 de Fontaine tienen más del 75 por ciento de estenosis orgánica en arterias periféricas y presentan alteraciones en la coagulación y en los lípidos plasmáticos. El objetivo de este estudio fue evaluar de forma controlada la influencia de la ingesta de los aceites de oliva virgen, aceite de oliva refinado y sus mezclas con aceite de pescado, junto con un programa de intervención de hábitos de vida que incluyen recomendaciones dietéticas, ejercicio moderado y descenso del consumo de tabaco, sobre la composición lipidica del plasma, en una población de pacientes con EVP durante un período de 15 meses. El estudio se realizó mediante un diseño aleatorio cruzado en el que 24 pacientes ingerían alternativamente, en períodos de 3 meses, los aceite de oliva virgen, oliva refinado y sus mezclas con un suplemento diario de 16 g de aceite de pescado refinado. Además, se incluyó un grupo control con 13 pacientes que no ingerían de forma habitual estos aceites, aunque sí siguieron el programa de intervención nutricional y de hábitos de vida. Se realizó un estudio de ingesta de alimentos y hábitos de vida cada 3 meses, así como de las modificaciones en la composición lipidica del plasma. Los resultados obtenidos indican que la intervención nutricional individualizada de pacientes con patología vascular por arteriosclerosis consigue que los sujetos incorporen a sus hábitos de vida una alimentación cada vez más sana y equilibrada junto con una disminución del consumo de tabaco y aumento del ejercicio físico moderado, lo que provoca una mejora en su calidad de vida. El consumo del aceite de pescado, conjuntamente con el consumo habitual de aceite de oliva, disminuyó significativamente los niveles de TG plasmáticos comparado con el consumo de aceite de oliva exclusivamente (AU)

The role of phytic acid in legumes: antinutrient or beneficial function?

This review describes the present state of knowledge about phytic acid (phytate), which is often present in legume seeds. The antinutritional effects of phytic acid primarily relate to the strong chelating associated with its six reactive phosphate groups. Its ability to complex with proteins and particularly with minerals has been a subject of investigation from chemical and nutritional viewpoints. The hydrolysis of phytate into inositol and phosphates or phosphoric acid occurs as a result of phytase or nonenzymatic cleavage. Enzymes capable of hydrolysing phytates are widely distributed in micro-organisms, plants and animals. Phytases act in a stepwise manner to catalyse the hydrolysis of phytic acid. To reduce or eliminate the chelating ability of phytate, dephosphorylation of hexa- and penta-phosphate forms is essential since a high degree of phosphorylation is necessary to bind minerals. There are several methods of decreasing the inhibitory effect of phytic acid on mineral absorption (cooking, germination, fermentation, soaking, autolysis). Nevertheless, inositol hexaphosphate is receiving increased attention owing to its role in cancer prevention and/or therapy and its hypocholesterolaemic effect.

Extra-virgin olive oil increases the resistance of LDL to oxidation more than refined olive oil in free-living men with peripheral vascular disease.

Patients with peripheral vascular disease (Fontaine stage II) are characterized by ischemia of the lower extremities, atherosclerosis and alteration of blood coagulation and fibrinolysis. A randomized, two-period, crossover design was used to compare the effects of extra-virgin (VO) and refined olive (RO) oils on plasma lipids and lipoprotein composition and LDL oxidation susceptibility in free-living men with peripheral vascular disease. The oils differed in their antioxidant profile (alpha-tocopherol: 300 vs. 200 mg/kg; phenolic compounds 800 vs. 60) and concentration but not in their fatty acid composition. Subjects were randomly assigned to two groups. The first group (n = 12) received VO with which to freely cook all meals for 3 mo, followed by a 3-mo wash-out period; they then received RO for the final 3 mo. The second group (n = 12) consumed the oils in the opposite order. Energy, fat, polyunsaturated fatty acids (PUFA) and alpha-tocopherol intakes were not different when patients consumed the two oils. Profiles of the major fatty acids in plasma and LDL were not different after consumption of VO and RO. The slope of the line for LDL oxidation vs. the line for copper concentration was significantly higher after the intake of RO than after the intake of VO. Total LDL taken up by macrophages was significantly greater when the men consumed RO rather than VO. We suggest that antioxidants present in VO may protect LDL against oxidation more than does RO in men with peripheral vascular disease.

Influence of dietary fish on fatty acid composition of the erythrocyte membrane in coronary heart disease patients.

This study examines the effects of dietary fish oil on the fatty acid composition of the erythrocyte membrane in persons with coronary heart disease. Thirty men with myocardial infarction were studied during three consecutive periods, during which they consumed 1) their habitual diet, 2) a diet specially designed to prevent ischaemic cardiopathy, and 3) a diet rich in polyunsaturated fat, in which fish was substituted for meat. At the end of each diet, fatty acid concentrations in the erythrocyte membrane were measured, and a 48 h recall dietary questionnaire was used to determine the types of foods consumed. Despite the increase in the intake of (n-3) polyunsaturated fatty acids (PUFA), the fatty acid composition of the erythrocyte membrane failed to reflect the greater dietary supply of eicosapentaenoic acid, and showed increased concentrations of stearic (C16) and palmitic (C18) acid. The increase in dietary (n-3) polyunsaturated fatty acids markedly increased 22:4 (n-6), 22:5 (n-6), 22:5 (n-3) and 22:6 (n-3) fatty acids.

Influence of dietary supplementation with fish on plasma fatty acid composition in coronary heart disease patients.

The effects of dietary supplementation with fish on plasma fatty acid levels were studied in 20 coronary heart disease patients who had suffered acute myocardial infarction. The study was divided into three periods: hospital admission, after 8 weeks on a heart-healthy diet designed for patients with ischemic heart disease, and after 4 weeks on an n-3 fatty acid-supplemented diet in which red meat was replaced with lean and fatty fish. At the end of each period, the subjects responded to a 48-hour recall questionnaire, so that we could assess their compliance with the diet, and blood samples were collected for the determination of plasma fatty acids. Stearic fatty acid was significantly decreased after the fish diet. n-7 and n-9 fatty acids showed no significant changes throughout the study. At the end of the 4-week period when the fish diet was consumed, linoleic acid and its long-chain derivative docosapentaenoic acid (22:5 n-6) were significantly increased. The most notable changes in n-3 series fatty acids at the end of the third period were the significant decrease in linolenic acid and the significant increase in its long-chain derivatives eicosapentaenoic (20:5 n-3) and docosahexaneoic acid (22:6 n-3). These changes in plasma fatty acid levels may have beneficial effects on coronary heart disease.

Influence of dietary fat on the lipid composition of perirenal adipose tissue in rats.

The influence of dietary fat on the composition of perirenal adipose tissue was studied in Wistar rats fed three experimental semisynthetic, isocaloric diets containing different qualities of fat (olive oil, butter and medium chain triglycerides + corn oil). Under these experimental conditions, the saturation index reflects the percentage of fatty acids supplied by each diet; this index was highest in animals fed the diet containing butter and lowest in the group in which olive oil was the dietary fat source. The amount of linoleic acid (the major component of the diunsaturation index) supplied by the diet is directly paralleled by levels of this fatty acid in perirenal adipose tissue, whereas the monounsaturation index in adipose tissues, considered an indicator of the dietary supply of monounsaturated fatty acids in the rat, failed to show a clearly proportional relationship between intake and perirenal adipose tissue levels.

Nutritional availability of magnesium and calcium in magnesium-supplemented diets.

The nutritive utilization of magnesium and calcium was studied using two different formulations of Mg: MgCO3 and an organic dietary Mg preparation. The influence of supplementation with the latter was also studied. The dietary organic magnesium did not modify food intake, which remained adequate in all animals used in the present experiments. Magnesium in both inorganic compound and organic preparation form was well absorbed; furthermore, absorption levels of the latter remained quite stable throughout the different experimental periods. Mg balance in both muscle and femur was similar in all groups studied. Digestive utilization of Ca and Ca content in the longissimus dorsi were higher in animals fed the organic Mg preparation while Ca levels in blood and femur were not affected.

Influence of hydrocortison acetate on the evolution of the nutritive utilization of calcium and phosphorus and their contents on the longissimus dorsi muscle during gestation in the rat.

The evolution of the nutritive utilization and plasma and muscular content of calcium and phosphorus in rats is studied, as well as the influence that hydrocortisone acetate has (4 mg/100 g weight and day), on them. In pregnant rats injected with saline solution, the retention of calcium is higher on the days 15-18 as a consequence of the increase on the net absorption of the cation. The balance of phosphorus reaches its maximum hight on days 18-21 of gestation, due to the decrease of the urinary excretion during these days. The administration of hydrocortisone acetate to pregnant rats originate a decrease of the net absorption and an increase of the urinary excretion of calcium and phosphorus, which leads to significantly lower balances than those of animals injected with saline solution. The hormone maintains the animals in a negative balance of phosphorus until day 18 of gestation. Besides, it impedes the high retention of calcium which is found with the control pregnant rats on days 15-18. In general, the content in calcium and phosphorus by gram of dry matter of Longissimus dorsi muscle is not modified during gestation. From day 9 of the treatment with hydrocortisone acetate a significant decrease of calcium and phosphorus of the muscle is observed, that in calcium is the more marked the more the treatment is prolonged. This effect seems to be due to the catabolic action of the hormone.