PROTECTION OF THE INTESTINAL MUCOSA FROM ANTINUTRITIONAL AND TOXIC DIETARY LECTINS BY PROBIOTIC DAIRY BACTERIA

ZÁRATE, GABRIELA; PÉREZ CHAIA

Tucumán

Simposio; IV International Symposium on Lactic Acid Bacteria: Food, Health and Applications; 2013

CERELA-CONICET

DISERTACION EN MESA REDONDA Many antinutritional and/or potentially toxic compounds are daily ingested in the diet by humans and animals. These substances could be endogenous components of food or exogenous contaminants. Among them, plant lectins are specific carbohydrate?]binding proteins that are widespread in legumes, seeds, cereals, and other plants of the Leguminosae and Gramineae Families that are used as farm feeds. As a general rule, these compounds are highly resistant to inactivation by cooking and by digestive processes, therefore they reach unaltered or at least retaining some of their biological activity to the intestinal lumen and/or blood circulation. Their effects in the host are diverse depending on their origin and concentration, so both toxic and biotherapeutics effects have been reported for some lectins. Toxicity could be acute or chronic with morphological and physiological changes in the intestinal mucosa such as shortening of microvilli and inhibition of digestive enzymes that conduce to a reduction of the absorptive function. Although these alterations could be initially unnoticed they lead to important nutritional deficiencies in the long term being their impact on health of significant level. In the last decades, researches on the probiotic properties of microorganisms suitable for the development of functional foods have significantly increased, as well as the interest of both industry and consumers on these healthy products. It has been demonstrated that probiotics can bind and metabolize toxins, carcinogens and antinutritional compounds from food and/or the gastrointestinal tract and even induce changes in the host physiology that lead to the decrease of the deleterious effects caused by these substances in the consumer?fs health. In this respect, we have observed that dairy propionibacteria have the ability to remove some dietary lectins by binding them on carbohydrates expressed on bacterial surfaces, which in turn decrease the toxic effects of lectins on intestinal epithelial cells (IEC). Consumption of propionibacteria at the same time than concanavalin A, a representative member of the mannose binding lectins family (used as model in our studies), reduced the incidence of structural and physiological lectin?]induced alterations in Balb/c mice suggesting that these microorganisms could be considered as a tool to avoid undesirable lectin-epithelia interactions. In the same manner other bacteria with appropriated cell wall carbohydrates moieties could be consumed as a part of human or animal diets to interfere with the recognition process between lectins and IEC and to protect the mucosa from these antinutritional compounds commonly present in food.