Title:The Antidiabetic Drug Metformin Attenuated Depressive and Anxiety-like Behaviors and Oxidative Stress in the Brain in a Rodent Model of Inflammation Induced by Lipopolysaccharide in Male Rats
Volume: 24
Issue: 13
Author(s): Faezeh Sadat Hosseini Kakhki, Amir Asghari, Zahra Bardaghi, Akbar Anaeigoudari, Farimah Beheshti, Hossein Salmani and Mahmoud Hosseini*
Affiliation:
- Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
Keywords:
Metformin, lipopolysaccharide, inflammation, depression, anxiety, oxidative stress.
Abstract:
Background: Inflammation is considered to be a link between diabetes and central
nervous system (CNS) disorders, including depression and anxiety. Metformin is suggested to
have antioxidant, anti-inflammatory, and mood-improving effects. The aim of the current research
was to investigate the effects of the antidiabetic drug metformin on depressive- and anxiety-
like behaviors and oxidative stress in the brain in a rodent model of inflammation induced
by lipopolysaccharide (LPS) in male rats.
Materials and Methods: The rats were treated as follows: (1) Vehicle instead of metformin and
lipopolysaccharide, (2) Lipopolysaccharide (1 mg/ kg) + vehicle instead of metformin, (3–5)
Lipopolysaccharide + 50, 100, or 150 mg/ kg of metformin. After the behavioral tests, including
open field (OF), elevated pulse maze (EPM), and force swimming (FS) tests, the brains were
removed, and malondialdehyde (MDA), nitric oxide (NO) metabolites, total thiol, catalase
(CAT) activity, interleukin-6 (IL-6) and superoxide dismutase (SOD) activity were determined.
Results: In the EPM, metformin increased the open arm time and entry and decreased closed
arm time and entry. In the FS test, metformin lowered the immobility and increased active time
compared to lipopolysaccharide. In the OF test, metformin increased total crossing and total
distance, time spent, traveled distance, and crossing number in the central zone. As a result of
metformin administration, IL-6, MDA, and NO metabolites were decreased while thiol content,
SOD, and CAT activity were increased.
Conclusion: The results indicated that the well-known antidiabetic drug metformin attenuated
depressive- and anxiety-like behaviors induced by inflammation in rats. These beneficial effects
are suggested to be due to their attenuating effects on neuroinflammation, oxidative stress, and
NO in the brain.