Pharmacological and computational analysis of the involvement of the 5-HT4 receptor in the antidepressant-like effect of N-(3-(phenylselanyl)prop-2-yn-1-yl)benzamide in mice.

The serotonin type 4 receptor (5-HT4R)shows promise as a target for treating major depressive disorder (MDD). Studies have demonstrated that 5-HT4R agonists have a faster antidepressant-like effect compared to conventional medications. Developing drugs that modulate this receptor could lead to faster and more effective MDD treatments. The compound N-(3-(phenylselanyl)prop-2-yn-1-yl)benzamide (SePB) induces an antidepressant-like effect in mice. The present study explored if the 5-HT4R mediates SePB's antidepressant effect. For this, male Swiss mice were treated with GR113808 (0.1 mg/kg, intraperitoneally - i.p.), a 5-HT4R antagonist, and SePB (10 mg/kg, intragastrically - i.g), and then subjected to the tail-suspension test (TST) and open-field test (OFT). In silico tests were conducted to analyze SePB's binding affinity to the 5-HT4R and identify participating amino acid residues. The administration of GR113808 blocked the antidepressant-like effect of SePB in the TST without changing locomotor activity in the OFT. Moreover, SePB exhibited a high binding affinity between the 5-HT4R (-7.9 kcal/mol) and the amino acid residues Leu298, Asp100, Thr97, Arg96, Glu80, Leu81, Cys184, Val185, and Phe186 seem to be important for this interaction. The involvement of the 5-HT4R in the antidepressant-like effect of SePB suggests potential for novel therapies in MDD.

Antinociceptive effect of N-(3-(phenylselanyl)prop-2-yn-1-yl)benzamide in mice: Involvement of 5-HT1A and 5-HT2A/2C receptors.

Pain strongly affects public health, both because of the patient suffering and the socioeconomic impact. The available drugs for pain treatment are not fully effective and have many adverse effects. Therefore, there is a need to obtain new analgesic compounds. This study evaluated the antinociceptive effect of N-(3-(phenylselanyl)prop-2-yn-1-yl)benzamide (SePB), an organoselenium compound containing the benzamide moiety, through time (15-120 min) and dose-response (1-50 mg/kg) curves in thermal and chemical mice models of nociception, as well as the involvement of the serotonergic system in this effect. The open-field test (OFT) was carried out to assess locomotor activity. SePB (10 mg/kg) induced an increase in the latency to nociception response in the tail immersion test from 30 min. In the dose-response curves, SePB at different doses reduced latency time to nociceptive response in the tail immersion and hot plate tests, and reduced the licking time in the glutamate test, demonstrating antinociceptive effect, without altering the locomotor activity of mice. WAY100635 (0.5 mg/kg, subcutaneously, a 5-HT1A receptor antagonist), ketanserin (0.3 mg/kg, intraperitoneally, a 5-HT2A/2C receptor antagonist), but not ondansetron (0.5 mg/kg, intraperitoneally, a 5-HT3 receptor antagonist), administered 15 min before SePB, prevented the increased latency to nociceptive response induced by SePB in the tail immersion test, demonstrating that 5-HT1A and 5-HT2A/2C receptors are involved in the antinociceptive effect of SePB. Upon more studies evaluating SePB antinociceptive effects in chronic pain models and its toxicity, this compound could be indicated as an interesting molecule to treat pain.