INVESTIGADORES
ZARATE Gabriela Del Valle
congresos y reuniones científicas
Título:
PROTECTION OF THE INTESTINAL MUCOSA FROM ANTINUTRITIONAL AND TOXIC DIETARY LECTINS BY PROBIOTIC DAIRY BACTERIA
Autor/es:
G. ZÁRATE AND A. PÉREZ CHAIA
Lugar:
Tucumán
Reunión:
Simposio; IV Simposio Internacional de Bacterias Lácticas; 2013
Institución organizadora:
CERELA-CONICET
Resumen:
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?s 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.