Anxiolytic-like action of 3-((4-methoxyphenyl)selanyl)-2-phenylbenzofuran (SeBZF3) in mice: A possible contribution of the serotonergic system

Anxiety disorders, characterized by high prevalence rates, cause psychiatric disabilities and are related to impairments in serotoninergic system function. Frequent anxiety recurrence, resistance, and drug adverse effects have driven searches for new therapies. We initially evaluated the anxiolytic-like activity of 3-selanyl-benzo[b]furan compounds (SeBZF1-5) (50 mg/kg, i.g.) in male Swiss mice using the light-dark test (LDT). The compound 3-((4-methoxyphenyl)selanyl)-2-phenylbenzofuran (SeBZF3) exhibited anxiolytic-like activity. SeBZF3 anxiolytic-like effects were also observed in the novelty-suppressed feeding test (NSFT) (50 mg/kg) and elevated plus-maze test (EPMT) (25 and 50 mg/kg). In the EPMT, anxiolytic-like effects of SeBZF3 (50 mg/kg) were abolished by pretreatment with p-chlorophenylalanine, a selective tryptophan hydroxylase inhibitor (100 mg/kg, i.p. for 4 days), suggesting the involvement of serotonergic mechanisms. Furthermore, we conducted experiments to investigate the synergistic effects of SeBZF3 subeffective doses (5 mg/kg, i.g.) in combination with fluoxetine (a selective serotonin reuptake inhibitor, 5 mg/kg, i.p.) or buspirone (a partial agonist of the 5-HT1A receptor, 2 mg/kg, i.p.). This coadministration resulted in pronounced synergistic effects. We also examined the effects of repeated oral treatment with SeBZF3 at doses of 1 and 5 mg/kg over 14 days and both reduced anxiety signals. In vitro and ex vivo findings revealed that SeBZF3 inhibited cerebral MAO-A activity. These findings collectively imply the potential involvement of serotonergic mechanisms in the anxiolytic-like activity of SeBZF3 in mice. These data offer contributions to the research field of organoselenium compounds and anxiolytics, encouraging the broadening of the search for new effective drugs while offering improved side effect profiles.

Depressive-like behavior and cognitive impairment induced by acute administration of dexamethasone: Pharmacological effects of 2-phenyl-3-(phenylselanyl)benzofuran in female Swiss mice

Synthetic glucocorticoid administration has been reported to play a role in depression and cognitive decline. The present study investigated the 2-phenyl-3-(phenylselanyl)benzofuran (SeBZF1) effects against the depressive-like behavior, memory impairment, and neurochemical alterations caused by acute dexamethasone administration in female Swiss mice. A dexamethasone dose-response curve (0.07-0.5 mg/kg, subcutaneous route, s.c.) was initially performed to validate the depressive-like behavior induction, in which the 0.25 mg/kg dose was more effective. Two experimental sets were performed to test the SeBZF1 (5 and 50 mg/kg, intragastric route, i.g.) pharmacological effect in this animal model. The 1st set revealed that the SeBZF1 reverses the dexamethasone-induced depressive-like behavior in the tail suspension test and in the splash test. In the 2nd experimental set, the compound effects of reversing the depressive-like behavior in the forced swimming test and the memory deficit in the Y-maze test induced by acute treatment with dexamethasone were demonstrated. Furthermore, SeBZF1 reversed the increase in the monoamine oxidase (MAO) activity in the prefrontal cortex (isoforms A and B) and in the hypothalamus (isoform A) caused by dexamethasone. However, no changes were observed in hippocampal MAO activity. Furthermore, animals treated with dexamethasone and SeBZF1 demonstrated a partially lower acetylcholinesterase activity in the prefrontal cortex compared with the induced group. In summary, the present study demonstrated that SeBZF1 reverses depressive-like behavior and memory deficits caused by acute dexamethasone treatment in female Swiss mice. Possibly the compound exerts its antidepressant-like action by increasing the availability of monoamines, while its effects on memory are still partially understood.