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Introduction The stem bark extract of Maerua angolensis DC. (Capparaceae) is used as a traditional remedy for management of anxiety, psychosis, and epilepsy. Aim of the Study We therefore aimed at evaluating the anxiolytic and antidepressant potential of the plant in mice models. Methods The dried stem bark was extracted with petroleum ether/ethyl acetate (50:50) mixture to obtain the extract, MAE. We employed Irwin's test to identify the preliminary behavioral and autonomic effects. Subsequently, MAE was administered per os to male mice and subsequently assessed, 1 h later, for anxiety parameters in the elevated plus maze (EPM) and the regular Suok tests. The forced swim (FST) and tail suspension (TST) tests were employed to assess the antidepressant potential of the extract (100-1000 mg kg−1). Results In our preliminary assay, MAE (100-5000 mg/kg) exhibited analgesic effects and a reduction in fear response in the Irwin's test. The spontaneous locomotor activity was reduced at 1000 mg/kg. Additionally, MAE (1000 mg/kg) increased the latency to PTZ-induced convulsions, and duration to sleep in the pentobarbitone induced sleeping time assay. MAE (1000 mg/kg), similar to diazepam, in the anxiolytic assay, increased the percentage time spent in the open arms while decreasing protected head dips and unprotected stretch attend postures in the EPM. Correspondingly, there was a reduction in anxiety-induced immobility and freezing in the Suok test (300 mg/kg) without loss of sensorimotor coordination. Additionally, there was a significant reduction in immobility duration in the FST (300 mg/kg) and TST (1000 mg/kg). Conclusion The petroleum ether/ethyl acetate fractions of Maerua angolensis stem bark possess anxiolytic and acute antidepressant effects in mice.

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Introduction Pseudospondias microcarpa (Anacardiaceae) is a plant widely used traditionally for treating various central nervous system disorders. A previous study in our laboratory confirmed that the hydroethanolic leaf extract (PME) of the plant produces an antidepressant-like effect in rodent models of behavioral despair. However, its effect on depressive-like behavior induced by chronic mild stress (CMS) and its time course of action are still unknown. In this context, the long-term effects of PME on cognitive function and depressive- and anxiety-like behavior caused by CMS were assessed. Methods Male ICR mice were exposed to CMS for nine weeks and anhedonia was evaluated by monitoring sucrose intake (SIT) weekly. PME (30, 100, or 300 mg kg-1) or fluoxetine (FLX) (3, 10, or 30 mg kg-1) was administered to the mice during the last six weeks of CMS. Behavioral tests—coat state, splash test, forced swimming test (FST), tail suspension test (TST), elevated plus maze (EPM), open field test (OFT), novelty suppressed feeding (NSF), EPM transfer latency, and Morris water maze (MWM)—were performed after the nine-week CMS period. Results When the mice were exposed to CMS, their SIT and grooming behavior reduced (splash test), their coat status was poor, they became more immobile (FST and TST), more anxious (OFT, EPM, and NSF), and their cognitive function was compromised (EPM transfer latency and MWM tests). Chronic PME treatment, however, was able to counteract these effects. Additionally, following two (2) weeks of treatment, PME significantly boosted SIT in stressed mice (30 mg kg-1, P<0.05; 100 mg kg-1, P<0.05; and 300 mg kg-1, P<0.001), as compared to four (4) weeks of treatment with FLX. Conclusion The present findings demonstrate that PME produces a rapid and sustained antidepressant-like action and reverses behavioral changes induced by chronic exposure to mild stressors.

Introduction The stem bark of Maerua angolensis DC. (Capparaceae) is traditionally used for management of epilepsy. Our aim was to evaluate the antiseizure potential and identify possible mechanisms by which the effects are registered. Methods The petroleum ether/ethyl acetate extract (100–1000 mg kg−1) was administered per os to male Sprague-Dawley rats after pretreatment with flumazenil (0.3 mg kg−1) or L-arginine (150 mg kg−1) or sildenafil (5 mg kg−1) and they subsequently received a subcutaneous injection of pentylenetetrazole (65 mg kg−1). Rats were observed for latency to and duration of myoclonic seizures and additionally the level of protection against oxidant markers and products was assessed in vitro and in vivo. Results The extract (300 and 1000 mg kg−1, p.o.) significantly delayed the onset and decreased the duration and frequency of PTZ-induced convulsions. The anticonvulsant effect of MAE (300 mg kg−1, p.o.) was reversed by pretreatment with flumazenil, L-arginine, or sildenafil. Also, MAE (300 mg kg−1) treatment reversed significantly PTZ-induced oxidative stress in rat brain tissue. Conclusion The petroleum ether/ethyl acetate fraction exhibits antiseizure activity by affecting GABAergic and nitric oxide-cGMP pathways. In addition, the extract protects against the generation of free radicals and the oxidative products of the PTZ-induced seizures.