Evaluation of ocludin e ZO-1 proteins expression in bariatric surgery rat intestine fragments

• Grant number: 18/10757-5
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2018
• Effective date (End): September 30, 2019
• Field of knowledge: Health Sciences - Medicine
• Principal researcher: Ita Pfeferman Heilberg
• Grantee: Maria Victória Lazarini Melo
• Home Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Bariatric surgery (BS) has become the most common surgical intervention as a means to lose weight. However, one of its long-term complication is an increased risk of nephrolithiasis, mainly due to elevation in urinary oxalate (Ox), whose underlying mechanisms have not been determined yet. In a recent experimental study, BS-induced fat malabsorption has been shown to modify the colonic permeability to Ox, increasing its passive and paracellular absorption, a process which involves tight junction proteins such as occludin and ZO-1. The main purposes of the present study are to evaluate the expression of occludin and ZO-1 in intestinal and colon fragments in a BS model in rats and to determine their association with fecal fat excretion and urinary Ox levels. The quantification of occludin and ZO-1 gene expression will be performed in intestinal fragments tissues of the biliopancreatic and alimentary limbs and the colon. These intestinal fragments have been obtained from male Wistar rats that had undergone BS or Sham procedures under conditions of either a high-fat diet supplemented with 1% of sodium Ox (BS-F+Ox and Sham-F+Ox) or a standard diet (BS and Sham) during 8 weeks. The results of biochemical analysis and fecal fat determination in the 24-hour urine samples and feces collected at 1 week before surgery (baseline) and at the end of experiment (final) from all groups will be compared.