Duodenal Toxicity of Dietary <i>Phaseolus vulgaris</i> Lectins in the Rat: An Integrative Assay

Abstract

It is now generally admitted that phytohemagglutinin (PHA) constitutes the main factor responsible for the dietary toxicity of raw kidney beans. In the growing rat, an impairment of growth is the unique expression of a malnutrition syndrome. The aim of this work was to precise to what extent the intestinal injuries may account for this malnutrition. PHA was administered for 9 days to growing rats at levels ranging from 0.0025 to 0.25% of food dry matter. One group of controls was fed ad libitum and other groups were restrained. In such conditions, PHA reduced the food intake when offered at a level higher than 0.04% as a linear function of the logarithm of lectin rate. Intestinal injuries were also dose-dependent: blebbing of microvilli and loss of alkaline phosphatase occurred at the smallest dose of PHA, cell loss occurred at higher doses. A compensatory hyperplasia was observed as a consequence of both intestinal injury and reduced food intake. Our main results are that, whatever may be the damages caused to the duodenal mucosa, the observed growth impairment was quasitotally imputable to the reduction of food intake.

Effects of Concanavalin A on intestinal brush border enzyme activity in broiler chickens

“…The sucrase activity in 3-week-old BBMV diminished significantly in the presence of Con A (T1) and when the lectin was pre-incubated with the enzyme (T3). Previous studies using Phaseolus vulgaris lectins have demonstrated that their specific interaction with membranes depends on the pattern of glycosylation of the mucosa (Begbie and King, 1985;Lafont et al, 1988), which can vary depending on diverse factors such as the age and diet composition (Sharma et al, 1997). These factors may partly explain the results obtained in the present work.…”

Oral Administration of Raw White Kidney Beans (Phaseolus Vulgaris L. Var. Beldia) Induces Overgrowth of Fecal Coliforms and Lactobacilli in Wistar Rats

“…"Pinto" (94.7 g/100 g body weight) during 8 days was remarkably reduced compared to control (65.5 g/100 g body weight). In 1988, Lafont et al [15] administered purified PHA for 9 days to growing rats at levels ranging from 0.0025% to 0.25% of food dry matter. They noticed that PHA reduced the food intake when offered at a level higher than 0.04%.…”

Binding of kidney bean (Phaseolus vulgaris) isolectins to differentiated human colon carcinoma Caco-2 cells and their effect on cellular metabolism.

“…25 In this in vitro study the direct interference of PHA isolectins with the cellular metabolism of differentiated Caco-2 cells can be investigated. To detect any differences in their effect upon the cellular metabolism, PHA-L4 and PHA-E4 were tested separately.…”

“…The Caco-2 cells were grown in Dulbecco's modified Eagle medium (DMEM) (Flow Laboratories, Amstelstad BV, Amsterdam, The Netherlands) supplemented with 1% (v/v) nonessential amino acids (Flow), 50 [ig of gentamicin/ml (Flow), 10 mM sodium bicarbonate (Flow), 25 mM Hepes (Flow), and 20% (v/v) fetal calf serum (FCS) (Sanbio BV, Uden, The Netherlands) and cultured at 37°C in a humidified atmosphere of 5% CO2 in air. The cells were seeded at 4.…”