Analysis of paracellular permeability and gut microbiota composition in murine model under high fat diet

• Grant number: 18/25088-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2019
• End date: March 31, 2021
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Licio Augusto Velloso
• Grantee: Caio Fernando Biolcatti
• Host Institution: Faculdade de Ciências Médicas (FCM). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 15/50278-0 - Anti-obesity effects of nutrients by hypothalamic FFA1 and FFA4 activation, AP.TEM

Abstract

The gastrointestinal epithelium is responsible for the internalization of substances through the body (both cellular and paracellular permeability) and also for the organism's defense, blocking away the entrance of antigens and pathogens. The paracellular permeability in the intestine is characterized by the passage of substances from the extracorporeal environment to inside the body through the space between the cells. In physiological conditions, the presence of tight junctions (TJs) in the enterocytes' basolateral portion regulates this traffic, selecting the substances allowed to pass between both environments. These TJs are directly influenced by diet-present substances, like saturated fatty acids, and by the composition of the gut microbiota, as the bacteria composing it may secrete harmful substances to TJs. The microbiota, in turn, is modulated by diet components and by physiological phenomena such as pregnancy. The understanding of these factors to the TJs integrity is utterly important since any structural dysfunctionality of TJs' proteins can deregulate the paracellular traffic, allowing pathogens to cross through the epithelial barrier towards the body, compromising the organism's homeostasis. In this way, this study's objective is to investigate the influence of both consumptions of high-fat diet and pregnancy, combined or not, on the composition of the bacteria which make up the gut microbiota and its connection to the enterocytes' permeability. Fecal samples will be collected for microbiota analysis and also the collection of difference intestinal portions will be made, for the verification of gene and protein expression by means of qPCR and immunohistochemistry.