Precocious gut maturation and immune cell expansion by single dose feeding the lectin phytohaemagglutinin to suckling rats

Abstract

The dietary lectin phytohaemagglutinin (PHA) induces gut growth and precocious maturation in suckling rats after mucosal binding. The present study investigated the dose range in which PHA provokes gut maturation and if it coincided with immune activation. Suckling rats, aged 14 d, were orogastrically fed a single increasing dose of PHA: 0 (control), 2, 10, 50 or 250 mg/g body weight (BW) in saline. The effect on gut, lymphoid organs and appearance of CD3 þ (T-lymphocyte) and CD19 þ (B-lymphocyte) cells in the small-intestinal mucosa was studied at 12 h (acute) and 3 d (late phase) after treatment. The low PHA doses (2 and 10 mg/g BW) induced intestinal hyperplasia without mucosal disarrangement but did not provoke gut maturation. Only the high PHA doses (50 and 250 mg/g BW) temporarily disturbed the intestinal mucosa with villi shortening and decrease in disaccharidase activities, and later after 3 d provoked precocious maturation, resulting in an increase in maltase and sucrase activities and decrease in lactase activity and disappearance of the fetal vacuolated enterocytes in the distal small intestine. Exposure to the high, but not to the low, PHA doses increased the number of mucosal CD19 þ and CD3 þ cells in the small intestine after 12 h, a finding also observed in untreated weaned rats aged 21 -28 d. In conclusion, there was a dose-related effect of PHA on gastrointestinal growth and precocious maturation that coincided with a rapid expansion of mucosal B-and T-lymphocytes, indicating a possible involvement of the immune system in this process.

The effect of early-life kidney bean lectin administration on pig performance in the peri-weaning period – a safety study

“…Several changes were observed during the study, among others in haematology and blood biochemistry, as compared with controls, however, it should be emphasized that all results, including the results obtained in the group treated with the high dose of kidney bean lectin, were within the physiological range for piglets. Nevertheless, it is known that lectins from legumes, including kidney bean lectins, may provoke immune system development (Prykhod'ko et al, 2009). Plant lectins may increase allergic reactions in humans and animals (Cordain et al, 2000;Lavelle et al, 2000).…”

“…Kidney bean lectin, a carbohydrate-binding protein, is constituted by a mixture of isoforms, PHA-E 4 , PHA-E 3 L, PHA-E 2 L 2 , PHA-EL 3 , PHA-L 4 , originally characterized by erythro-and leuco-agglutinating activity (Nordman et al, 1964;Leavitt et al, 1977). After gastric gavage it manifested strong promitotic activity in gut mucosa, and stimulated immune and endocrine systems in suckling piglets -described jointly as precocious maturation (Rådberg et al, 2001;Thomsson et al, 2007;Prykhod'ko et al, 2009). Importantly, maturation effects in the gastrointestinal tract were induced without systemic absorption of lectin (Linderoth et al, 2006).…”

Feeding with dairy Propionibacterium acidipropionici CRL 1198 reduces the incidence of Concanavalin-A induced alterations in mouse small intestinal epithelium

“…On the contrary, single or few oral inoculations of PHA to suckling rats and piglets induced structural and functional maturation of the gut evidenced as a decreased villi height, increased proliferation and crypt depth and a shift in the expression of enterocytes disaccharidases to an adult-type characterized by a decreased lactase and increased sucrase and maltase activities. In consequence, PHA has been proposed as an inductor of precocious maturation of the gut in order to better prepare the farm animals to digest and absorb the post weaning feed, as well as a treatment of mammals having an immature intestine and a therapy for individuals with a defective growth of the mucosa during total parenteral nutrition (Fitzgerald et al, 2001;Linderoth et al, 2005Linderoth et al, , 2006Prykhod'ko, Fed'kiv, Linderoth, Pierzynowski, & Westrom, 2009;Radberg et al, 2001;Thomsson, Rantzer, Westrom, Pierzynowski, & Svendsen, 2007).…”

Induction of precocious intestinal maturation in T-cell deficient athymic neonatal rats

“…We have previously shown that gut maturation can be induced precociously in suckling rats by enteral provocation with phytohaemagglutinin (PHA) - a lectin[ 15 , 16 ], or proteases[ 17 ], mimicking the naturally occuring processes at weaning. Furthermore, provocation with PHA had effects on the thymus and the recruitment of CD3 + T-lymphocytes to the gut mucosa[ 16 ]. In fact, it has been suggested that natural GI development at weaning is dependent on T-cell activation in rats[ 18 ].…”