Influence of prebiotic and probiotic administration on gene expression of toll-like receptors 4 (TLR-4) in rats with Non-Alcoholic Fatty Liver Disease (NAFLD)

• Grant number: 14/03474-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2014
• End date: June 30, 2015
• Field of knowledge: Health Sciences - Nutrition
• Principal Investigator: Claudia Cristina Alves Pereira
• Grantee: Angélica Carreira dos Santos
• Host Institution: Instituto de Saúde e Sociedade (ISS). Universidade Federal de São Paulo (UNIFESP). Campus Baixada Santista. Santos , SP, Brazil

Abstract

Nonalcoholic fatty liver disease (NAFLD) is characterized by fat accumulation in hepatocytes (hepatic steatosis) in the absence of alcohol intake (ROCHA et al., 2007). The gut-liver axis is one way by which bacteria and their potential hepatotoxic products reach the liver. These compounds can be classified as pathogen-associated molecular patterns (PAMPs). The PAMPS in the innate immune system have receptors for many pathogens, the pattern recognition receptors (PRR), and among the 28 PRRs, the Toll-like receptors (TLRs)(ALISI et al., 2012; SANTOS, 2013; KAWAI and AKIRA , 2006). It is considered that the imbalance of the intestinal microbiota causes increase in LPS and other components of the cell walls of bacteria that pass into the portal circulation (GONZÁLEZ, 2011). The interaction of LPS to the TLR- 4 receptor stimulates the macrophage to respond immediately triggering the intracellular signal pathways which result in the synthesis of inflammatory cytokines (Costa, 2012). Nutritional alternatives capable of modifying the composition of the gut microbiota, such as probiotics and/or prebiotics, have been proposed in order to beneficially modulate the overgrowth of bacteria that may contribute to the pathogenesis of NAFLD (IACONO et al., 2011). From this information, it is important that further studies in animal models are conducted to clarify the molecular effects involved in the condition of NAFLD and duration of supplementation with nutritional compounds as pre and probiotics. (AU)