The Effect of Mucuna pruriens on Depression-like Behavior Induced by a Mild Traumatic Brain Injury in Rats Is Associated with a Decrease in Brain Nitrite and Nitrate Levels

Traumatic brain injury (TBI), even when mild, has been associated with the presence of depression. Depression is a mood disorder characterized by persistent negative thoughts and sadness and is challenging to treat due to the multiple mechanisms involved in its pathophysiology, including increased nitric oxide (NO) levels. There are no completely safe and effective pharmacological strategies to treat this disorder. <i>Mucuna pruriens</i> (MP) has been shown to possess neuroprotective properties by regulating inflammatory responses and nitric oxide synthase activity. In this study, we evaluated the antidepressant-like effect of MP in male Wistar rats with induced mild traumatic brain injury (mTBI). MP extract (50 mg/kg i.p.) was administered immediately after mTBI and every 24 h for five days. We used the rats' preference for sucrose consumption to assess the presence of depression-like behavior and analyzed the nitrite and nitrate levels in their cerebral cortex, striatum, midbrain, and nucleus accumbens. Untreated animals with mTBI showed a reduced preference for sucrose than those treated with MP, whose preference for sucrose was similar to that of sham animals. Increased nitrite and nitrate levels were observed in different brain regions in the TBI subjects; however, this increase was not observed in MP-treated animals. MP reduces behavior associated with depression and the brain NO levels in rats with mTBI.