Effect of exposure to dexamethasone on miRNA expression in the endocrine pancreas and glucose homeostasis of pregnant rats.

Author(s)

Patricia Rodrigues Lourenço Gomes

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2015-02-06

Examining board members

Silvana Auxiliadora Bordin da Silva; Angelo Rafael Carpinelli; José Guilherme Cecatti; José Donato Júnior; Joel Claudio Heimann

• Advisor: Silvana Auxiliadora Bordin da Silva

Abstract

This study investigated whether treatment with glucocorticoids during pregnancy alters the energetic, hormonal and molecular maternal metabolism, function of pancreatic islets and correlative changes of miRNAs. Were used 80 rats divided into two groups of 40 animals, one group designed to aging up one year after weaning, and the next group destined to experimentation at 20th day of gestation, both arranged: CTL - control, CTL-Dex - control treated with dexamethasone for 6 days, P - pregnant rats and P-Dex - pregnant rats treated with dexamethasone from 14th to 19th day of pregnancy. Pancreatic islets were collected for large-scale analysis of miRNA expression. The target genes were screened and confirmed by qPCR. Finally it was investigated the mechanism of modulation of glucose homeostasis through qPCR and Western Blot. We can be observed numerous changes resulting from therapy with DEXA in pregnancy concluded that the association of treatment to the pregnancy period modulates members of the miRNA-29 family causing an imbalance in glucose homeostasis through long-term failure in exocytotic machinery, triggered by the downregulation of the progesterone and its receptor promoting injury in the pancreatic islet remodeling process in late pregnancy. (AU)

• FAPESP's process: 11/01568-5 - Effect of dexamethasone on the expression of miRNA in the endocrine pancreas in pregnant rats
• Grantee: Patrícia Rodrigues Lourenço Gomes
• Support Opportunities: Scholarships in Brazil - Doctorate