"Expression of proteins communication and cell junctions in physiological and pathological events in the gastric mucosa of horses"

• Grant number: 14/18635-5
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: November 01, 2014
• End date: January 31, 2016
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal Investigator: Francisco Javier Hernandez Blazquez
• Grantee: Vânia Pais Cabral
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The high morbidity of gastric lesions have been described in horses. The imbalance between protective and harmful factors alter the intrinsic defense mechanisms of the gastric mucosa, resulting in injuries that can develop into ulcers in the aglandular (80%) or glandular (20 %)region. Besides the production of mucus, intrinsic protective factors may be the cause of this difference. Among these the gap junctions (GAP) and the proteins associated with them (connexins) are known to play an important role in homeostasis, epithelial restoration and cellular defense system. Various connexins have been reported in the stomach of various species, such as CX 32, 26, 40 and 43. Other junction cell adhesion molecules such as E-cadherin, N-cadherin and beta and alfa-catenin have an important role in maintaining the structural integrity of the epithelium and differentiation and cell proliferation. Changes in the expression patterns of these molecules, such as reduction, loss or ectopic location (subcellular) have been reported in various types of diseases. These changes may be associated with the formation of lesions and stomach ulcers in horses by interfering with the processes of tissue repair. Human studies describe that Cx32 has an inverse correlation with the Ki67 proliferative factor in the epithelium of the gastric mucosa. Despite the high incidence of gastric ulcers in horses, the presence of gap junctions and adhesion proteins of the gastric mucosa in horses is still poorly investigated, with only one report of the presence of Cx 32 exclusively in the glandular epithelium. In this context, the study of proteins junction is necessary for a better understanding of the functions and behavior of cell-cell interaction in the gastric mucosa in healthy horses and or in gastric disorder. Thus, checking the correlation of cellular junctions and distribution of connexins will assist in diagnostic procedures and serve as a parameter in understanding the pathogenesis of several gastropathy and / or morphofunctional evaluation of the gastric mucosa of horses submitted to different diets and food handling or livestock. In this context, the present design aims to study the role of proteins and junction of connexins in the gastric mucosa (aglandular and glandular) of horses from slaughterhouses or autopsy material, with or without macroscopic tissue changes identified by histology, transmission electronmycroscpy and immunohistochemistry techniques, identifying and localizing connexins, cadherins (E and N) and catenins (beta and alfa) and the cell proliferation marker Ki67 to check for correlations between the expression of these molecules and cell proliferation.