Determining the relative concentration of hemopressin in the brains of mice subjected to deprivation and sleep restriction

• Grant number: 14/01263-8
• Support Opportunities: Scholarships in Brazil - Master
• Start date: January 01, 2015
• End date: January 31, 2016
• Field of knowledge: Biological Sciences - Pharmacology - Biochemical and Molecular Pharmacology
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Jair Ribeiro Chagas
• Grantee: Gabriela Polster
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Neuropeptides have a role in the functioning of the whole organism, in particular in the central nervous system. The activity of many neuropeptides, especially the interaction with their receptors, has been widely studied. However the mechanisms of generation of active neuropeptides from active or inactive precursors and degradation mechanisms of these compounds has been less detailed in the literature. Our interest was then returned to study peptides generated by intracellular proteolysis extralisossomal (eg proteasomo and oligopeptidases) which may have an important physiological role in modulating signal transduction G-protein coupled receptors (GPCRs) and tyrosine kinases. Currently hundreds of intracellular peptides were identified in human cell lines and in brains of mice, but the physiological function of these peptides remain completely unknown. Recent examples as hemopressin, Pro- Phe - Val- Asn -Leu -Lys -Leu- Ser-His, and - RVD and RV- hemopressine appear to be neuropeptide endogenous ligands of cannabinoid receptors CB1, but with opposite actions. If endogenous intracellular peptides play functional roles, as seems to be the case based on previous studies, their levels should be regulated under various physiological and pathological conditions. Therefore in this project we aim to develop a method that can quantify the absolute concentration of these peptides in different regions of the mouse brain, allowing later can evaluate physiological and pathological changes of intracellular peptides in the central nervous system in existing models. In our case, the group preliminary results demonstrate changes in the expression and activity of metalloproteases in paradoxical sleep deprivation, where the CB1 cannabinoid receptor appears to play a role. As an application of the methodology will seek to quantify the neuropeptide family hemopressin this model. (AU)