Effects of vitamin A deficiency on mucosal immunity and response to intestinal infection in rats

• Published in: Nutrition (Burbank, Los Angeles County, Calif.) Los Angeles County, Calif.), 2011-02, Vol.27 (2), p.227-232
• Main Authors: Yang, Yi, M.D., Ph.D, Yuan, Yajie, M.D, Tao, Yuehong, M.D., Ph.D, Wang, Weiping, M.D., Ph.D
• Format: Article
• Language: English
• Subjects: animal models; Animals; Biological and medical sciences; Children & youth; Dendritic Cells - immunology; Diet; Dietary Supplements; digestive system diseases; Disease Models, Animal; Feeding. Feeding behavior; food pathogens; Fundamental and applied biological sciences. Psychology; Gastroenterology and Hepatology; Gastrointestinal Tract - immunology; Gastrointestinal Tract - microbiology; Gastrointestinal Tract - pathology; immune response; Immune system; Immunity; Immunity, Mucosal; Immunoglobulin A - immunology; Interferon-gamma - immunology; Interleukin-12 - immunology; intestinal infection; intestinal mucosa; Intestinal Mucosa - immunology; Intestinal Mucosa - microbiology; Intestinal Mucosa - pathology; Intestine; Mucosa; mucosal immunity; Murine model; Myeloid Differentiation Factor 88 - immunology; Rats; Rats, Sprague-Dawley; Respiratory Tract Infections - complications; Respiratory Tract Infections - immunology; Respiratory Tract Infections - pathology; Rodents; Salmonella; Salmonella typhimurium - metabolism; salmonellosis; Toll-Like Receptor 2 - immunology; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vitamin A; Vitamin A - administration & dosage; Vitamin A deficiency; Vitamin A Deficiency - complications; Vitamin A Deficiency - immunology; vitamin deficiencies; vitamin supplements
• ISSN: 0899-9007; 1873-1244
• DOI: 10.1016/j.nut.2009.11.024

Abstract Objective Vitamin A deficiency is associated with an increased incidence of infectious respiratory and alimentary tract diseases in children, and vitamin A supplementation can prevent and assist in treating these diseases. To clarify the mechanisms of these associations, we investigated the effects of vitamin A deficiency on mucosal immunity to intestinal infection in rats. Methods Specific pathogen-free Sprague-Dawley rats received a vitamin A-free diet, with ( n = 20) or without ( n = 20) vitamin A supplementation. Intestinal infection was induced by oral inoculation of salmonella in 10 rats in each group. The rats were killed 3 d after infection was induced, and we measured the number, maturation, and activation of dendritic cells; the expression of Toll-like receptors 2 and 4; mRNA level of myeloid differentiation primary response gene (88) (MyD88, pattern-recognition receptors and their adapter protein); immune cytokine production in the intestinal mucosa; and the amount of secretory immunoglobulin A in the gut. Results In vitamin-A deficient rats, the number of mucosal dendritic cells and the production of IL-12 markedly increased; the mucosal expressions of Toll-like receptor 2 and MyD88 were up-regulated, and secretions of interferon-γ and secretory immunoglobulin A were decreased. Infection aggravated the damage to the intestinal mucosa and lowered immunity in vitamin-A deficient rats. Conclusion Vitamin A deficiency damaged both humoral and cellular immunity in the mucosa. Modulation of dendritic cells is likely an important mechanism through which vitamin A deficiency affects mucosal immune responses against infection.