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Raúl López‐arnau

Institut de Biomedicina de la Universitat de Barcelona

5 papers in the library · 29 citations · publishing 2022-2025

Papers

Structure-activity relationships of serotonergic 5-MeO-DMT derivatives: insights into psychoactive and thermoregulatory properties

Molecular Psychiatry March 14, 2024 Pol Puigseslloses, Gabriel Ketsela, Nicola Weiss et al. 23 citations

All tested 5-MeO-tryptamines selectively bind to 5-HT1A receptors over 5-HT2A receptors, with computational docking predicting better interaction in the 5-HT1A binding pocket. These compounds also interact with the serotonin transporter (SERT), where molecular size of the amino group influences affinity. 5-MeO-pyr-T acts as the most potent partial 5-HT releaser. All tryptamines elicit the head twitch response in mice, indicating potential hallucinogenic effects primarily mediated by 5-HT2A receptors, but 5-HT1A activation attenuates this response. Tryptamines producing stronger hypothermic responses via 5-HT1A tend to show lower hallucinogenic effects, highlighting opposing roles of the two receptors. Some compounds with low hallucinogenic effects remain potent 5-HT2A agonists, offering insight into non-hallucinogenic therapeutic ligands.

3,4-Methylenedioxy methamphetamine, synthetic cathinones and psychedelics: From recreational to novel psychotherapeutic drugs

Frontiers in Psychiatry October 3, 2022 Jordi Camarasa, Pol Puigseslloses, Edurne Urquizu et al. 5 citations

Conventional psychiatric drugs often fail due to limited efficacy, slow onset, or side effects. Psychoactive substances, historically used for spiritual and recreational purposes, have shown therapeutic potential for disorders like post-traumatic stress disorder and treatment-resistant depression when administered under medical supervision with psychotherapy. Drugs such as MDMA, ketamine, psilocybin, and LSD have yielded successful clinical outcomes. New psychoactive substances (NPS), including synthetic cathinones and tryptamines, despite their illicit use, expand the library of potential treatments, as many were originally synthesized for therapeutic aims. This review examines the evidence and properties needed for NPS to become viable therapeutic compounds.

Neuropharmacology of halogenated DMT analogs: psychoplastogenic and antidepressant properties of 5-Br-DMT, a psychedelic derivative with low hallucinogenic potential

Molecular Psychiatry October 21, 2025 Pol Puigseslloses, Núria Nadal‐gratacós, Berta Fumàs et al. 1 citation

A novel class of halogenated DMT derivatives—5-F-DMT, 5-Cl-DMT, and 5-Br-DMT—was characterized for pharmacological activity and therapeutic potential. Halogen substitution at the 5-position modulates receptor affinity across serotonin receptors and the serotonin transporter. 5-Br-DMT activated the 5-HT2A receptor but did not induce the head twitch response in mice, suggesting non-hallucinogenic activity. It upregulated immediate early genes linked to neuroplasticity in the mouse prefrontal cortex and hippocampus and promoted dendritic growth in cortical neurons. A single 10 mg/kg dose of 5-Br-DMT in a mouse model of stress-induced depression significantly reduced depressive-like behavior, indicating rapid antidepressant effects. The findings highlight 5-Br-DMT as a non-hallucinogenic psychoplastogen with antidepressant properties.

Next-Generation MDMA Analogue SDMA: Pharmacological and Metabolic Insights

ACS Chemical Neuroscience December 2, 2025 Nina Kastner, Núria Nadal‐gratacós, Selina Hemmer et al.

Replacing the 1,3-benzodioxole group in MDMA (ecstasy) with a 1,3-benzoxathiole yields two analogues, SDA and SDMA, that interact with monoamine transporters similarly to MDMA but with key differences. SDA and SDMA inhibit dopamine and norepinephrine transporters more potently than MDMA and act as partial releasers at serotonin and dopamine transporters. Metabolism studies show SDA and SDMA are cleared faster, while MDMA and MDA degrade only weakly. In mice, SDMA does not produce rewarding effects, unlike MDMA, and SDA only shows a preference for the drug-paired compartment at the lowest dose. SDMA shares similar locomotor and hyperthermic profiles with MDMA, whereas SDA induces increased hyperlocomotion and more sustained hyperthermia. SDMA may be a safer candidate for further study.

The psychedelic phenethylamine 25C-NBF, a selective 5-HT2A agonist, shows psychoplastogenic properties and rapid antidepressant effects in male rodents

Molecular Psychiatry November 14, 2025 Núria Nadal‐gratacós, Pol Puigseslloses, Laura Hernández‐guzmán et al.

Three novel phenethylamine derivatives—25C-NBF, 25B-NBF, and 25I-NBF—show high affinity and selectivity for the 5-HT2A receptor, with signaling bias toward Gq over β-arrestin pathways similar to serotonin. In mice, they cause moderate head-twitch responses without affecting movement or sensorimotor gating. No rewarding or reinforcing effects were observed, and accumbal dopamine levels in rats remained unchanged. 25C-NBF promotes dendritogenesis, spinogenesis, and increased Bdnf mRNA in vitro and in vivo, reduces despair-like behavior after acute stress, and produces rapid antidepressant effects in a chronic corticosterone model of anhedonia. These findings suggest 25C-NBF may offer a fast-acting antidepressant with no abuse potential or sensorimotor deficits.