Administration of α-lipoic acid and silymarin attenuates aggression by modulating endocrine, oxidative stress and inflammatory pathways in mice

Abstract

Aggression, a highly prevalent behavior among all the psychological disorders having strong association with psychiatric imbalance, neuroendocrine changes and neurological disturbances (including oxidative stress & neuroinflammation) require both pharmacological and non-pharmacological treatments. Focusing the preclinical neuroendocrine determinants of aggression, this interventional study was designed to elucidate the curative effect of antioxidants on aggression in male mice. Adult albino male mice (n = 140) randomly divided into two main treatment groups for α-lipoic acid (ALA) and silymarin with 5 subgroups (n = 10) for each curative study, namely control, disease (aggression-induced), standard (diazepam, 2.5 mg/kg), low dose (100 mg/kg) and high dose (200 mg/kg) treatment groups of selected antioxidants. Resident-intruder paradigm and levodopa (L-dopa 375 mg/kg, p.o.) induced models were used for aggression. Effect of antioxidant treatment (i.e., 21 days bid) on aggression was assessed by evaluating the changes in aggressive behavior, oxidative stress biomarkers superoxide dismutase, catalase, glutathione, nitrite and malondialdehyde (SOD, CAT, GSH, nitrite & MDA), neurotransmitters (dopamine, nor-adrenaline and serotonin), pro-inflammatory cytokines tumor necrosis factor-α and interleukin- 6 (TNF-α & IL-6) along with serum testosterone examination. This study showed potential ameliorative effect on aggressive behavior with both low (100 mg/kg) and high (200 mg/kg) doses of antioxidants (ALA & silymarin). Resident-intruder or L-dopa induced aggression in male mice was more significantly tuned with ALA treatment than silymarin via down regulating both oxidative stress and inflammatory biomarkers. ALA also exhibited notable effects in managing aggression-induced disturbances on plasma testosterone levels. In conclusion, ALA is more effective than silymarin in attenuating aggression in mice.

Keywords: Aggression; Animals behavior; Neuroinflammation; Oxidative stress; Silymarin; α-Lipoic acid.