RESEARCH ARTICLE


Social State Influences Memory in Novel Object Recognition Test Through Oxidative Stress Balance in Male Rats



Hamidreza Famitafreshi1, Morteza Karimian2, *
1 Department of Physiology, Tehran University of Medical Science, International Campus, Tehran, Iran
2 Department of Physiology, Tehran University of Medical Science, Tehran, Iran


© 2018 Famitafreshi and Karimian.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: (https://creativecommons.org/licenses/by/4.0/legalcode). This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Department of Physiology, Tehran University of Medical Science, Enghelab St, Poorsina St, Tehran, Iran; Tel: 009802166419484; E-mail: karimian@tums.ac.ir


Abstract

Objective:

Social isolation is associated with adverse effects on brain functions. According to previous studies, the reduction of oxidative stress improves cognitive functions. Memory performance is dependent on hippocampus and prefrontal function. The aim of this study is to show that impairment of memory in object recognition test in isolation state is accompanied by deregulation of oxidative stress balance in related areas.

Methods and Materials:

In this study, 14 male Sprague-Dawley rats were randomly divided into two groups as follows: social and isolation. Socialization and isolation plus one week of acclimatization occurred for fourteen days. At the end of the study, after performing behavioral test, (novel object recognition test) rats were anesthetized and sacrificed. After preparation of tissues in controlled condition, oxidative stress status in hippocampus and prefrontal cortex for Malondialdehyde (MDA), glutathione and nitrite/nitrate was assessed.

Results:

MDA in the hippocampus and prefrontal cortex was higher in isolated rats compared to social rats. Glutathione and nitrite/nitrate in the hippocampus and prefrontal cortex were lower in isolated rats compared to social rats. Memory performance in novel object recognition test both in short term and long term was better in social rats.

Conclusion:

Memory performance in novel object recognition test is influenced by social and oxidative stress status. So improving memory is possible through socialization and improvement of antioxidant status.

Keywords: Malondialdehyde, Glutathione, Nitrite/nitrate, Novel object recognition test and isolation, Oxidative stress, Prefrontal function.