Preventive and curative effects of probiotics in atopic patients

Abstract

Normally, the transport of allergens through the intestinal epithelia to the blood is limited. It is hypothesised that if these compounds arrive in the blood circulation, they must percolate through the epithelial cell layer. Thus, food allergy (and thus atopic eczema) implies an increased intercellular leakage of the gut wall. Such increased intercellular leakage is thought to be caused by a slightly changed cellular morphology due to a slight cytopathologic effect because of both a limited decay of the cytoskeleton and a slightly reduced turgor. These events may be due to a reduced production of intracellular metabolic energy in the epithelial cells due to an increased concentration of familiar, frequently occurring, potentially toxic bacterial metabolites, i.e., d-lactic acid and/or ethanol. In this hypothesis we suggest that adequate probiotics can (i) prevent the increased characteristic intestinal permeability of children with atopic eczema and food allergy, (ii) can thus prevent the uptake of allergens, and (iii) finally can prevent the expression of the atopic constitution. The use of adequate probiotic lactobacilli, i.e., homolactic and/or facultatively heterolactic l-lactic acid-producing lactobacilli, reduces the intestinal amounts of the bacterial, toxic metabolites, d-lactic acid and ethanol by fermentative production of merely the non-toxic l-lactic acid from glucose. Thus, it is thought that beneficial probiotic micro-organisms promote gut barrier function and both undo and prevent unfavourable intestinal micro-ecological alterations in allergic individuals.