Cashew (Anacardium occidentale) Extract: Possible Effects on Hypothalamic-Pituitary-Adrenal (HPA) Axis in Modulating Chronic Stress.

Depression presents a significant global health burden, necessitating the search for effective and safe treatments. This investigation aims to assess the antidepressant effect of the hydroethanolic extract of Anacardium occidentale (AO) on depression-related behaviors in rats. The depression model involved 42 days of unpredictable chronic mild stress (UCMS) exposure and was assessed using the sucrose preference and the forced swimming (FST) test. Additionally, memory-related aspects were examined using the tests Y-maze and Morris water maze (MWM), following 21 days of treatment with varying doses of the AO extract (150, 300, and 450 mg/kg) and Imipramine (20 mg/kg), commencing on day 21. The monoamines (norepinephrine, serotonin, and dopamine), oxidative stress markers (MDA and SOD), and cytokines levels (IL-1ß, IL-6, and TNF-α) within the brain were evaluated. Additionally, the concentration of blood corticosterone was measured. Treatment with AO significantly alleviated UCMS-induced and depressive-like behaviors in rats. This was evidenced by the ability of the extract to prevent further decreases in body mass, increase sucrose consumption, reduce immobility time in the test Forced Swimming, improve cognitive performance in both tests Y-maze and the Morris water maze by increasing the target quadrant dwelling time and spontaneous alternation percentage, and promote faster feeding behavior in the novelty-suppressed feeding test. It also decreased pro-inflammatory cytokines, corticosterone, and MDA levels, and increased monoamine levels and SOD activity. HPLC-MS analysis revealed the presence of triterpenoid compounds (ursolic acid, oleanolic acid, and lupane) and polyphenols (catechin quercetin and kaempferol). These results evidenced the antidepressant effects of the AO, which might involve corticosterone and monoaminergic regulation as antioxidant and anti-inflammatory activities.

Antidepressant, anti-amnesic and vasoprotective effect of Bombax costatum Pellegr. & Vuillet aqueous stem bark extract on chronic mild unpredictable stress induced in rat.

ETHNOPHARMACOLOGICAL RELEVANCE: Bombax costatum Pellegr. & Vuillet is used traditionally in Northern Cameroon to treat memory impairment, anxiety, insomnia and depression. AIM OF THE STUDY: Investigating the effect of Bombax costatum stem bark aqueous extract (BC) on depression associated with amnesia and vascular disorder, using a chronic mild unpredictable stress (CMUS) model in rats for 30 days. MATERIALS AND METHODS: Sucrose Preference Test (SPT), Forced Swimming Test (FST), corticosteronemia, brain serotonin and dopamine level were evaluated as indices of antidepressant-like effect. The Novel Object Recognition Task (NOR), the Morris Water Maze (MWM) and acetylcholinesterase activity in the hippocampus were also used to verify memory integrity. Oxidative and nitrosative stress markers, the lipid profile and atherogenic index were estimated in blood serum to assess vasoprotective effect. Chlorophenylalanine and haloperidol, were used to delineate the extract's mechanism of action. RESULTS: CMUS induced a decrease in sucrose preference and swimming time in the SPT and FST respectively while BC (27.5 and 55 mg/kg) increased sucrose preference and swimming time. Increments in these parameters were however reversed by the treatment of rats with chlorophenylalanine a serotonin synthesis inhibitor and haloperidol a D2 receptor antagonist. An increase in blood corticosterone level, prefrontal cortex malondialdehyde and nitric oxide concentrations were reversed by the extract. Moreover, BC increased the time spent in the target quadrant of the MWM test and the discrimination index in the NOR test. This was associated with an increase in hippocampus superoxide dismutase and catalase levels, a decrease in acetylcholine esterase level, total blood cholesterol and atherogenicity index compared to CMUS group. CONCLUSION: Thirty days CMUS induces a depressive state in rats. BC reverses this condition when administered alongside stress exposure. This antidepressive effect is associated with antiamnesic, antioxidant and vasoprotective actions, suggesting its use as a potential candidate in the management of major depressive disorder.

Anxiolytic and antidepressant effects of Ziziphus mucronata hydromethanolic extract in male rats exposed to unpredictable chronic mild stress: Possible mechanisms of actions.

ETHNOPHARMACOLOGICAL RELEVANCE: Ziziphus mucronata (ZM) is used traditionally in the treatment of mood and depression. However, no existing scientific data is confirming this traditional claim. AIM OF THE STUDY: The present study was planned to investigate the anxiolytic and antidepressant-like effects of this plant in a stressed-induced depression model in rats. MATERIALS AND METHODS: Depressive-like behaviors were induced by exposing rats to different stress paradigms daily for 30 days. A sucrose preference test was performed to assess anhedonia in rats. Anxiety and depression-related behavior were assessed. The oxidative parameters (lipid peroxidation, SOD and catalase activities) were evaluated. Pindolol and Flumazenil were also used to assess the mechanism of action of ZM extract. RESULTS: The results showed that chronic administration of ZM (150, 300, and 600 mg/kg, p.o., 30 days) and imipramine treatment (20 mg/kg, p.o, 30 days) remarkably (P < 0.05) reversed the UCMS-induced behavioral changes observed in stress vehicle treated rats by reducing sucrose preference, decreased the immobility period in the FST and latency in NSF. Besides, ZM (300 and 600 mg/kg, p.o., 30 days) raised the percentages of time spent and number of open arms entries as well as the number of transitions. Also, ZM (300 mg/kg, (P < 0.05) decreased lipid peroxidation and increased both SOD and catalase activities (300 and 600 mg/kg, (P < 0.05)). These aforementioned behavioral indices were also completely nullified by pindolol a ß-adrenoceptors blocker and 5-HT 1A/1B receptor antagonist but not by flumazenil, a benzodiazepine receptors antagonist. CONCLUSION: ZM improved symptoms of anxiety and depression in behavioral despair paradigm in chronically stressed rats. The observed effects could be due to its capacities to restore the antioxidant status, and probably the modulation of monoamines transmissions.