The effects of natural and modified clinoptilolite on intestinal barrier function and immune response to LPS in broiler chickens

The protection of intestinal barrier function and the anti-inflammatory effects of natural clinoptilolite (NCLD and modified clinoptilolite (MCLI) were investigated in broilers that were repeatedly challenged with lipopolysaccharide (LPS). A total of 288 1-d-old broiler chicks were divided equally into three treatment groups: control, NCLI-treated (2%) and MCLI-treated (2%). Half of the birds from each treatment group were challenged with 0.9% NaCl solution or LPS (250 mu g/kg body weight, administered orally) at 16, 18 and 21 d of age. The results indicated that, prior to LPS challenge, the diet had no effect on bird growth performance (P > 0.05). The oral administration of LPS was also not associated with any significant changes in poultry performance (P > 0.05). In LPS-challenged birds that were pretreated with NCLI (2%) or MCLI (2%), the LPS-induced increases in the plasma and intestinal mucosa concentrations of TNF-alpha, IL-1 beta, IL-2, IL-6, IL-4 and IL-10 were dramatically attenuated. Additionally, significant decreases in the plasma D-lactic acid and diamine oxidase (DAO) levels were found in birds that were pretreated with NCLI or MCLI. Furthermore, both NCLI and MCLI reduced the sICAM-1 concentration in the intestinal mucosa. In conclusion, NCLI and MCLI are able to prevent the LPS-induced intestinal mucosa damage and inflammatory response in vivo. These beneficial effects suggest that NCLI and MCLI act as anti-inflaminatory agents in part by inhibiting neutrophil infiltration and hyperactivation and by suppressing the secretion of various plasma and intestinal mucosa inflammatory mediators. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.