Moving towards a systems psychiatry paradigm embraces the inherent complex interactions across all levels from micro to macro and necessitates an integrated approach to treatment. Cortical 5-HT receptors are key primary targets for the effects of serotonergic psychedelics. However, the therapeutic mechanisms underlying psychedelic therapy are complex and tra...
Research on classical psychedelics (psilocybin, LSD and DMT) and entactogen, MDMA, has produced a renaissance in the search for more effective drugs to treat psychiatric, neurological and various peripheral disorders. Psychedelics and entactogens act though interaction with 5-HT2A and other serotonergic receptors and/or monoamine reuptake transporters. 5-HT,...
Abstract Background and Aims The hallucinogenic drug psilocybin is being widely tested in humans for the treatment of psychiatric disorders. Psilocybin and other psychedelics are proposed to work through serotonin 2a (5-HT2a) receptors, which are tightly linked to immune function. The purpose of the present study was to assess the effects of a single dose of...
There is increasing interest in the therapeutic potential of psilocybin. In rodents, the serotonin precursor, 5-hydroxytryptophan (5-HTP) and psilocybin induce a characteristic 5-HT2A receptor (5-HT2AR)-mediated head twitch response (HTR), which is correlated with the human psychedelic trip. We examined the role of other serotonergic receptors and the trace ...
Summary Psilocin, the active compound in Psilocybe sp. mushrooms, is a serotonergic psychedelic that has recently gained renewed interest due to its potential as a therapeutic tool. Despite promising clinical findings, the underlying signaling mechanisms and brain region-specific effects of psilocin and other psychedelic drugs remain unclear. Psilocin, like ...
There is much excitement surrounding recent research of promising, mechanistically novel psychotherapeutics - psychedelic, anesthetic, and dissociative agents - as they have demonstrated surprising efficacy in treating central nervous system (CNS) disorders, such as mood disorders and addiction. However, the mechanisms by which these drugs provide such profo...
Classic psychedelics refer to substances such as lysergic acid diethylamide (LSD), psilocybin, ayahuasca, and mescaline, which induce altered states of consciousness by acting mainly on 5-HT2A receptors. Recently, the interest of psychedelics as pharmacological treatment for psychiatric disorders has increased significantly, including their use on problemati...
IntroductionMescaline (3,4,5-trimethoxyphenethylamine) is one of the oldest hallucinogens, with evidence of use dating back 5700 years. Mescaline is a naturally occurring alkaloid found in cacti, mainly in the peyote cactus (Lophophora williamsii) and in the cacti of the Echinopsis genus. Since the prohibition of psychoactive substances in the early 70s, res...
Psychedelics including lysergic acid diethylamide (LSD) and psilocybin temporarily alter subjective experience through their neurochemical effects. Serotonin 2a (5-HT2a) receptor agonism by these compounds is associated with more diverse (entropic) brain activity. We postulate that this increase in entropy may arise in part from a flattening of the brain's c...
Pharmacotherapy of depression is characterized by the delayed onset of action, chronic treatment requirements, and insufficient effectiveness. Ketamine, with its rapid action and long-lasting effects, represents a breakthrough in the modern pharmacotherapy of depression. The current review summarizes the latest findings on the mechanism of the antidepressant...
Abstract Psilocybin therapy for depression has started to show promise, yet the underlying causal mechanisms are not currently known. Here we leveraged the differential outcome in responders and non-responders to psilocybin (10mg and 25mg, 7 days apart) therapy for depression - to gain new insights into regions and networks implicated in the restoration of h...
Abstract Preliminary clinical findings, supported by preclinical studies employing behavioral paradigms such as marble-burying, suggest that psilocybin may be effective in treating obsessive-compulsive disorder. On this background, we set out to explore 1) the role of 5-HT2A and 5-HT1A receptors in the effect of psilocybin on marble-burying; 2) the effect of...
Introduction Obsessive Compulsive Disorder (OCD) is a psychiatric disorder associated with suffering and disability. The serotoninergic system is implicated in the neurobiological processes of OCD and serotonin reuptake inhibitors (SRIs) are the first-line treatment. However, clinical improvement after starting SRIs can take long and patients may not fully r...
Introduction The 5-HT2A agonist classic psychedelic, psilocybin (O-phosphoryl-4-hydroxy-N,N-dimethyltryptamine) is a tryptophan, indole-based alkaloid present in up to 2% of certain hallucinogenic “magic” mushroom species; typically Psilocybe azurescens, semilanceata, and cyanescens,. In addition, mushrooms may contain psilocin (4-hydroxy-N,N-dimethyltryptam...
The last decade has seen a remarkable resurgence of interest in psychedelic drugs such as psilocybin (from magic mushrooms) LSD and DMT (dimethyl tryptamine - the active ingredient of ayahuasca). This has been driven by the discovery that these psychedelics all act agonists of 5-HT2A receptors. Human imaging studies have revealed this action leads to profoun...
The psychedelic 5-HT2A receptor (5HT2AR) agonist psilocybin (or the active metabolite psilocin) has emerged as potential useful drug for various neuropsychiatric diseases, with a rapid onset of therapeutic activity. However, the mechanisms responsible for such effects remain incompletely characterized. We aimed to study in vitro pharmacological profile and i...
IntroductionMajor depressive disorder remains a prevalent world-wide health problem. Currently available antidepressant medications take weeks of dosing, do not produce antidepressant response in all patients, and have undesirable ancillary effects.Areas coveredThe present opinion piece focuses on the major inroads to the creation of new antidepressants. The...
RNA editing is a process by which post-transcriptional changes of mRNA nucleotides alter protein function through modification of the amino acid content. The 5HT2C serotonin receptor, which undergoes 32 distinct RNA-editing events leading to 24 protein isoforms, is a notable example of this process. These 5HT2C isoforms display differences in constitutive ac...
There is increasing interest in the therapeutic potential of psilocybin in psychiatric disorders. In common with other serotonergic psychedelics, psilocybin is thought to act via the 5-HT2A receptor (5-HT2AR). Serotonin is the endogenous ligand of 5-HTR. In rodents, the serotonin precursor, 5-hydroxytryptophan (5-HTP), and psilocybin, induce a characteristic...
Background Preliminary clinical findings, supported by preclinical studies employing behavioral paradigms such as marble-burying, suggest that psilocybin may be effective in treating obsessive-compulsive disorder. Aims To explore 1) the role of 5-HT2A and 5-HT1A receptors in the effect of psilocybin on marble-burying; 2) the effect of staggered versus bolus ...
