TPN decreases IL-4 and IL-10 mRNA expression in lipopolysaccharide stimulated intestinal lamina propria cells but glutamine supplementation preserves the expression

• Published in: Shock (Augusta, Ga.) Vol. 15; no. 4; p. 318
• Main Authors: Fukatsu, K, Kudsk, K A, Zarzaur, B L, Wu, Y, Hanna, M K, DeWitt, R C
• Format: Journal Article
• Language: English
• Published: United States 01.04.2001
• Subjects: Animal Feed; Animals; Cytokines - metabolism; Enzyme-Linked Immunosorbent Assay; Gastrostomy; Gene Expression Regulation - drug effects; Glutamine - pharmacology; Glutamine - therapeutic use; Immunoglobulin A - biosynthesis; Immunoglobulin A - genetics; Interleukin-10 - biosynthesis; Interleukin-10 - genetics; Interleukin-4 - biosynthesis; Interleukin-4 - genetics; Intestinal Mucosa - drug effects; Intestinal Mucosa - immunology; Intestinal Mucosa - metabolism; Intestine, Small - drug effects; Intestine, Small - immunology; Intestine, Small - metabolism; Laparotomy; Lipopolysaccharides - pharmacology; Lymphoid Tissue - drug effects; Lymphoid Tissue - metabolism; Male; Mice; Mice, Inbred ICR; Parenteral Nutrition, Total - adverse effects; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - biosynthesis; Weight Loss
• ISSN: 1073-2322
• DOI: 10.1097/00024382-200115040-00012

Total parenteral nutrition (TPN) decreases intestinal IgA and levels of Th2 cytokines, interleukin (IL)-4, and IL-10 within the supernatants of intestinal homogenates. These cytokines are known to stimulate IgA production in vitro by cells of the gut-associated lymphoid tissue (GALT). Glutamine (GLN) supplementation of TPN normalizes GALT mass and cytokine levels. Because intestinal homogenates contain mucosa which itself is a source of cytokines, it was unclear whether cytokines change within the GALT itself. This study investigates dietary effects on IL-4 and IL-10 cytokine mRNA expression within isolated GALT lamina propria cells after lipopolysaccharide (LPS) stimulation. Prospective randomized experimental trials were used in this study. Fifty-nine mice were randomized to chow, intravenous TPN (IV-TPN), intragastric TPN (IG-TPN), complex enteral diet (CED), or 2% GLN-supplemented TPN (GLN-TPN). In experiment 1, animals were fed chow, IV-TPN, IG-TPN, or CED for 5 days and received intraperitoneal LPS (100 microg/kg BW), and then were sacrificed 1 h later. Intestine was harvested for GALT lamina propria. Total RNA was extracted from lamina propria cells and cytokine mRNA for IL-4, and IL-10 was measured by reverse transcriptase polymerase chain reaction. IgA levels of intestinal washing were also measured with ELISA. In experiment 2, mRNA for IL-4 and IL-10, and intestinal IgA levels were measured in mice fed chow, IV-TPN, or GLN-TPN as in experiment 1. Both IL-4 and IL-10 mRNA expression decreased significantly in IV-TPN mice compared to chow or CED feeding. IG-TPN resulted in IL-10 mRNA expression significantly lower than chow or CED but significantly better than IV-TPN. GLN preserved IL-4 and IL-10 mRNA levels, which correlated with intestinal IgA levels. Route and type of nutrition as well as GLN influence message for the Th2 type IgA-stimulating cytokines, IL-4 and IL-10, within the primary site of GALT IgA production, the lamina propria.