Reversão de sintomas comportamentais tipo-esquizofrenia e alterações neuroquímicas induzidos por cetamina pela administração de ácido alfa-lipóico sozinho e combinado à clozapina em camundongos

Abstract

Schizophrenia is partially mimicked by the repeated administration of ketamine (KET) being this model sensitive to atypical antipsychotics. Oxidative imbalance is an important alteration seen in schizophrenia. Alpha-lipoic acid (ALA) is a natural acid synthesized in human tissues presenting antioxidant properties. Herein we aimed to determine the effect of ALA alone or combined with clozapine (CZP) in the reversal of KET-induced alterations. Adult male mice received KET or saline during 7 days. From the 8 th to 14th days, saline, ALA (100 mg/kg), CZP 2.5 or 5 mg/kg were added. Schizophrenia-like symptoms were evaluated by prepulse inhibition (PPI) of the startle and locomotor activity (positive - like), social preference (negative - like) and Y maze (cognitive - like). Oxidative alterations (reduced glutathione - GSH and lipid peroxidation - LP) and nitrite in the prefrontal cortex (CPF), hippocampus (HC) and striatum (ST) and BDNF in the CPF were also addressed. Ketamine caused deficits in PPI, working memory, social interaction together with hyperlocomotion. Additionally, decreases in GSH, nitrite and BDNF and increases in LP were observed. ALA alone reversed KET - induced behavioral alterations. It also reversed the decreases in GSH in the HC, BDNF and increase in LP (CPF, HC and ST). The combination CZP 2.5 + ALA reversed behavioral and some neurochemical parameters. However, CZP 5 + ALA caused motor impairment. Overall, ALA seems to present an atypical antipsychotic-like profile reversing KET - induced positive and negative - like symptoms. The mechanism partially involves antioxidant, neurotrophic and nitrergic pathways. The combination with CZP presented positive results mainly with the lower dose.