The effect of nobiletin on behavioral function in elevated plus maze and forced swimming tests in intrahippocampal amyloid beta-induced model of Alzheimer's disease in the rat

Background and Objective: Alzheimer's disease (AD) is the most common form of dementia that is considered a chronic and progressive syndrome, that leads to the irreversible loss of neurons, particularly in the cortex and hippocampus. In this study, we considered whether nobiletin has any effect on behavioral function in elevated plus maze and forced swimming tests in amyloid beta-induced model of AD in the rat.   Materials and Methods: 32 male rats were randomly divided into four groups as follows: group A (sham), group B (sham+nobiletin), which were administrated nobiletin (10 mg/kg) daily one hour after surgery for one week via gavage, group C (Aβ): which amyloid β1-40 (2 nanomol/2 µl) was injected into the hippocampal region (CA1) bilaterally, and group D (Aβ + nobiletin), which was also administrated nobiletin (10 mg/kg). Furthermore, two behavioral tests including elevated plus maze and forced swimming tests were used to assess performance.   Results: Analysis of performance in elevated plus maze showed a significant increase in open arm time in nobiletin-treated Aβ group versus Aβ group (p<0.05). In addition, performance in forced swimming test showed a non-significant decrease in nobiletin-treated Aβ group versus Aβ group.   Conclusion: Taken together, these findings suggest that nobiletin could reduce anxiety in amyloid beta-induced model of AD in the rat with no significant effect on depression.