Possible involvement of L-arginine-nitric oxide pathway in the antidepressant activity of Auraptene in mice.

Background: Depression is one of the most common mental illnesses worldwide. Nitric oxide (NO) is involved in the pathophysiology of depression. Auraptene (a coumarin derivative) has been shown to possess pharmacological effects on neurological diseases.

Purpose: The present study aimed to investigate the possible role of the NO pathway in Auraptene antidepressant effects in male mice.

Methods: Behavioral tests were used to assess depression-like behaviors. The mice received Auraptene at 10, 30, and 100 mg/kg, the combination of the sub-effective (ineffective) dose of Auraptene (10 mg/kg) and L-NAME, and the combination of the effective dose of Auraptene (30 mg/kg) and L-arginine. Finally, OFT, TST, FST, brain, serum MDA level, antioxidant capacity, hippocampus, and serum NO level were measured.

Results: The data analysis showed that Auraptene (30 mg/kg) improved depression-like behaviors. Auraptene (30 mg/kg) also significantly reduced serum NO levels (P < 0.05) and significantly increased serum MDA (10 mg/kg, P < 0.05). Auraptene at 30 mg/kg also increased serum antioxidant capacity (P < 0.01). Co-administration of L-NAME and the sub-effective dose of Auraptene enhanced the effects of Auraptene. However, co-administration of the effective dose of Auraptene and L-arginine reduced the impacts of Auraptene.

Conclusions: The results showed that Auraptene causes antidepressant effects in a dose-dependent manner and acts as a prooxidant at 100 mg/kg, and exacerbates oxidative stress. The antidepressant effects of this active molecule are exerted by reducing the NO level in the hippocampus and serum, increasing the antioxidant capacity, and reducing the MDA level in the serum.