Evaluation of the effects of environmental enrichment on parvalbumin interneurons and extracellular matrix in the hippocampus and prefrontal cortex of rats

• Grant number: 22/16011-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): February 01, 2023
• Effective date (End): January 31, 2024
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Alexandre Hiroaki Kihara
• Grantee: Renata Silva Jorge
• Host Institution: Centro de Matemática, Computação e Cognição (CMCC). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil

Abstract

The hippocampus is a well-known structure due to its function in obtaining new memories and spatial navigation. Engagement in specific activities, such as working memory and decision-making, may involve other brain regions, such as the prefrontal cortex. The communication between these two regions allows for proper coordination for carrying out tasks. Interneurons that express parvalbumin (PV), when inhibited by contemporary techniques such as chemogenetics, generate memory deficits. These neurons are surrounded by perineuronal nets (PNNs), part of the extracellular matrix, which arise during development in an experience-dependent manner. In adult life, PNNs restrict plasticity, consolidating learning and stabilizing synapses. Exposure to environmental enrichment provides physical and mental challenges. The enriched environment generates neuronal changes, such as an increase in dendritic length and density, and in the number of synaptic buttons. This project aims to evaluate the performance of rats submitted to environmental enrichment in a working memory task in the y-maze. We will also assess the impact on i) parvalbumin (PV)-positive interneurons, and ii) PNNs, using Wisteria floribunda agglutinin (WFA) labeling, in the hippocampus and medial prefrontal cortex. With this, we intend to reveal the impact of the enriched environment on inhibitory interneurons and PNNs. In this way, the enriched environment can be used with greater propriety in possible therapeutic strategies to treat neuronal disorders that generate cognitive alterations. It should be noted that this proposal will be supported by research groups based at UFABC, USP and the University of California, Los Angeles (UCLA).