OPEN Foundation

Menu
Search
Close this search box.

OPEN Foundation

Ketamine-induced modulation of the thalamo-cortical network in healthy volunteers as a model for schizophrenia

April 20, 2015 / Ketamine, Neuroscience, Papers, Psychology, Psychotic Disorders, Publications / By / , , , , , ,

Abstract

BACKGROUND:

Schizophrenia has been associated with disturbances of thalamic functioning. In the light of recent evidence suggesting a significant impact of the glutamatergic system on key symptoms of schizophrenia, we assessed whether the modulation of the glutamatergic system via blockage of the NMDA-receptor might lead to changes of thalamic functional connectivity.

METHODS:

Based on the “ketamine-model” of psychosis we investigated changes in cortico-thalamic functional connectivity by intravenous ketamine challenge during a 55 minutes resting-state scan. 30 healthy volunteers were measured with pharmacological functional magnetic resonance imaging (fMRI) using a double-blind, randomized, placebo-controlled, crossover design.

RESULTS:

Functional connectivity analysis revealed significant ketamine-specific changes within the “thalamus hub network”, more precisely an increase of cortico-thalamic connectivity of the somatosensory and temporal cortex.

CONCLUSIONS:

Our results indicate that changes of thalamic functioning as described for schizophrenia can be partly mimicked by NMDA-receptor blockage. This adds substantial knowledge about the neurobiological mechanisms underlying the profound changes of perception and behaviour during the application of NMDA-receptor antagonists.

Höflich, A., Hahn, A., Küblböck, M., Kranz, G. S., Vanicek, T., Windischberger, C., … & Guertel, W. (2015). Ketamine-induced modulation of the thalamo-cortical network in healthy volunteers as a model for schizophrenia. The international journal of neuropsychopharmacology. http://dx.doi.org/10.1093/ijnp/pyv040
Link to full text

A Note on the Docking of some Hallucinogens to the 5-HT2A Receptor

April 20, 2015 / DMT, Mescaline / Cacti, Papers, Pharmacology & Chemistry, Publications / By / ,

Abstract

The activation of 5-HT2A receptors by the binding of some ligands produces several altered states of consciousness in humans. The knowledge of the manner a hallucinogen interacts with this receptor should be the first step to know how these chemicals transfer information to produce the final biological effect(s). Here, we present the results of a docking study of some hallucinogens (LSD, mescaline, DMT, 25I-NBOMe and others), to a recent model of the 5-HT2A receptor. The rigid and flexible residues approach es were employed. The best approach is to allow conformational flexibility to the residues of the binding site. The Val-156 residue appears to be common to all flexible docking results and all molecules interact with the transmembrane 3 helix. The other interactions are particular to each molecule.

Gómez-Jeria, J. S., & Robles-Navarro, A. (2015). A Note on the Docking of some Hallucinogens to the 5-HT2A Receptor. Journal of Computational Methods in Molecular Design, 5(1), 45-57.
Link to full text

The hallucinogenic world of tryptamines: an updated review

April 16, 2015 / DMT, LSD, Mushrooms / Psilocybin, Papers, Pharmacology & Chemistry, Psychology, Publications / By / , , , ,

Abstract

In the area of psychotropic drugs, tryptamines are known to be a broad class of classical or serotonergic hallucinogens. These drugs are capable of producing profound changes in sensory perception, mood and thought in humans and act primarily as agonists of the 5-HT2A receptor. Well-known tryptamines such as psilocybin contained in Aztec sacred mushrooms and N,N-dimethyltryptamine (DMT), present in South American psychoactive beverage ayahuasca, have been restrictedly used since ancient times in sociocultural and ritual contexts. However, with the discovery of hallucinogenic properties of lysergic acid diethylamide (LSD) in mid-1900s, tryptamines began to be used recreationally among young people. More recently, new synthetically produced tryptamine hallucinogens, such as alpha-methyltryptamine (AMT), 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and 5-methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT), emerged in the recreational drug market, which have been claimed as the next-generation designer drugs to replace LSD (‘legal’ alternatives to LSD). Tryptamine derivatives are widely accessible over the Internet through companies selling them as ‘research chemicals’, but can also be sold in ‘headshops’ and street dealers. Reports of intoxication and deaths related to the use of new tryptamines have been described over the last years, raising international concern over tryptamines. However, the lack of literature pertaining to pharmacological and toxicological properties of new tryptamine hallucinogens hampers the assessment of their actual potential harm to general public health. This review provides a comprehensive update on tryptamine hallucinogens, concerning their historical background, prevalence, patterns of use and legal status, chemistry, toxicokinetics, toxicodynamics and their physiological and toxicological effects on animals and humans.

Araújo, A. M., Carvalho, F., de Lourdes Bastos, M., de Pinho, P. G., & Carvalho, M. (2015). The hallucinogenic world of tryptamines: an updated review. Archives of toxicology, 1-23. https://dx.doi.org/10.1007/s00204-015-1513-x
Link to full text

Symposium about psychedelic research at Utrecht University

December 6, 2021 / Publications / By

On Thursday May 7th there will be a symposium on academic research with psychedelic drugs at Utrecht University. This symposium is organized by the student society Brainwave (Neuroscience Utrecht University), in collaboration with the OPEN Foundation.

Speakers:

Leon Kenemans – Professor Psychopharmacology Utrecht University.

Mendel Kaelen – PhD student Imperial College London and board member OPEN Foundation.

Joost Breeksema – President OPEN Foundation and harm reduction expert.

Barbara van Zwieten-Boot – College ter Beoordeling van Geneesmiddelen (Medicines Evaluation Board).

Leon Kenemans will open the symposium by providing a general overview of the brain mechanisms of various psychoactive drugs. Following this, Joost Breeksema will introduce the topic of psychedelic drugs, and argue for the relevance of modern research with psychedelics. Subsequently, Mendel Kaelen will talk about the brain mechanisms of psychedelics on the basis of recent research at Imperial College London. There he studies the brain mechanisms of LSD and the effects of LSD on music perception. Next, Barbara van Zwieten-Boot, will talk about the potential risks of medicines. Finally, there will be discussion between the speakers with the possibility for questions by the audience.

Brainwave created a Facebook event at which people can register themselves for this symposium. People without a Facebook account can register here.

The language of the symposium will be part English and part Dutch. Mendel Kaelen and Joost Breeksema will speak English. Leon Kenemans and Barbara van Zwieten-Boot will speak in Dutch.

Symposium over psychedelisch onderzoek aan Universiteit Utrecht

December 2, 2021 / Uncategorized / By

Op donderdag 7 mei organiseert studievereniging Brainwave (Neurowetenschappen Universiteit Utrecht) in samenwerking met Stichting OPEN een symposium over wetenschappelijk onderzoek naar psychedelica.

Sprekers:

Leon Kenemans – Professor Psychofarmacologie Universiteit Utrecht.

Mendel Kaelen – PhD student Imperial College Londen en bestuurslid Stichting OPEN.

Joost Breeksema – Voorzitter Stichting OPEN en harm reduction expert.

Barbara van Zwieten-Boot – College ter Beoordeling van Geneesmiddelen.

Leon Kenemans zal beginnen met een algemeen overzicht van de werking van verschillende psychoactieve stoffen in het brein. Joost Breeksema zal vervolgens het onderwerp psychedelica introduceren en op basis van historisch en huidig onderzoek beargumenteren waarom hedendaags onderzoek naar dit soort middelen zo interessant en relevant is. Hierna zal Mendel Kaelen dieper ingaan op de werking van psychedelica in het brein. Onder andere aan de hand van  studies die de afgelopen jaren zijn gedaan aan Imperial College Londen, waar hij momenteel promotieonderzoek doet naar hersenmechanismen van LSD en de effecten van LSD op muziekperceptie. Vervolgens zal Barbara van Zwieten-Boot spreken over de risico’s van bepaalde medicijnen. Tot slot zal er een debat plaatsvinden tussen de sprekers en zal er ook ruimte zijn voor vragen vanuit het publiek.

Studievereniging Brainwave heeft een Facebook event aangemaakt waar men zich kan aanmelden voor dit symposium. Mensen zonder Facebook kunnen zich aanmelden via de volgende link.

De voertaal zal deels Engels en deels Nederlands zijn. Mendel Kaelen en Joost Breeksema zullen in het Engels spreken. Leon Kenemans en Barbara van Zwieten-Boot zullen Nederlands spreken.

Mania following use of ibogaine: A case series

April 14, 2015 / Depressive Disorders, Iboga / Ibogaine, Papers, Psychology, Publications, Substance Use Disorder / By / , , ,

Abstract

BACKGROUND:

Ibogaine is a naturally occurring hallucinogen with postulated anti-addictive qualities. While illegal domestically, a growing number of individuals have sought it out for treatment of opiate dependence, primarily in poorly regulated overseas clinics. Existing serious adverse events include cardiac and vestibular toxicity, though ours is the first report of mania stemming from its use.

OBJECTIVES:

To report on a case series of psychiatric emergency room patients whose unregulated use of ibogaine resulted in mania in three patients with no prior diagnosis of bipolar illness.

METHODS:

Review and summarize charts of three cases. Relevant literature was also reviewed for discussion.

RESULTS:

Two cases of reported ibogaine ingestion for self-treatment of addictions, and one for psycho-spiritual experimentation resulted in symptoms consistent with mania. No prior reports of mania were found in the literature, and the literature suggests growing popularity of ibogaine’s use.

CONCLUSIONS:

The three cases presented demonstrate a temporal association between ibogaine ingestion and subsequent development of mania.

SCIENTIFIC SIGNIFICANCE:

In light of these cases, clinicians faced with a new onset mania may benefit from careful substance use and treatment history, specifically regarding opiates. In the vulnerable and often desperate addiction population, in particular, the number of patients seeking this treatment appears to be growing. We advise clinicians to be prepared for discussing the safety, efficacy, and paucity of good data regarding ibogaine with patients who may be considering its use.

Marta, C. J., Ryan, W. C., Kopelowicz, A., & Koek, R. J. (2015). Mania following use of ibogaine: A case series. The American Journal on Addictions. https://dx.doi.org/10.1111/ajad.12209
Link to full text

Ketamine and other N-methyl-D-aspartate receptor antagonists in the treatment of depression: a perspective review

April 13, 2015 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / , , , , , ,

Abstract

Current pharmacotherapies for major depressive disorder (MDD) and bipolar depression (BDep) have a distinct lag of onset that can generate great distress and impairment in patients. Furthermore, as demonstrated by several real-world effectiveness trials, their efficacy is limited. All approved antidepressant medications for MDD primarily act through monoaminergic mechanisms, agonists or antagonists with varying affinities for serotonin, norepinephrine and dopamine. The glutamate system has received much attention in recent years as an avenue for developing novel therapeutics. A single subanesthetic dose infusion of the noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist ketamine has been shown to have rapid and potent antidepressant effects in treatment-resistant MDD and BDep. In a reverse translational framework, ketamine’s clinical efficacy has inspired many preclinical studies to explore glutamatergic mechanisms of antidepressant action. These studies have revealed enhanced synaptic plasticity/synaptogenesis via numerous molecular and cellular mechanisms: release of local translational inhibition of brain-derived neurotrophic factor and secretion from dendritic spines, mammalian target of rapamycin activation and glycogen synthase kinase-3 inhibition. Current efforts are focused on extending ketamine’s antidepressant efficacy, uncovering the neurobiological mechanisms responsible for ketamine’s antidepressant activity in biologically enriched subgroups, and identifying treatment response biomarkers to personalize antidepressant selection. Other NMDA receptor antagonists have been studied both preclinically and clinically, which have revealed relatively modest antidepressant effects compared with ketamine but potentially other favorable characteristics, for example, decreased dissociative or psychotomimetic effects; therefore, there is great interest in developing novel glutamatergic antidepressants with greater target specificity and/or decreased adverse effects.

Iadarola, N. D., Niciu, M. J., Richards, E. M., Voort, J. L. V., Ballard, E. D., Lundin, N. B., … & Zarate, C. A. (2015). Ketamine and other N-methyl-D-aspartate receptor antagonists in the treatment of depression: a perspective review. Therapeutic Advances in Chronic Disease. https://dx.doi.org/10.1177/2040622315579059
Link to full text

Concise synthesis of N,N-dimethyltryptamine and 5-methoxy-N,N-dimethyltryptamine starting with bufotenine from Brazilian Anadenanthera ssp..

April 10, 2015 / Biology & Ethnobotany, DMT, Papers, Pharmacology & Chemistry, Publications / By / , , , ,

Abstract

Bufotenine (1, 5-hydroxy-N,N-dimethyltryptamine) was isolated from seeds of Anadenanthera spp., a tree widespread in the Brazilian cerrado, using an efficient acid-base shakeout protocol. The conversion of bufotenine into N,N-dimethyltryptamine (4) and 5-methoxy-N,N-dimethyltryptamine (5) was accomplished through an innovative and short approach featuring the use of novel bufotenine-aminoborane complex (7). Furthermore, an easy methodology for conversion of bufotenine into 5-hydroxy-N,N,N-trimethyltryptamine (6) was well-established. This is the first study that highlights bufotenine as a resource for the production of N,N-dimethyltryptamines for either pharmacological and toxicological investigations or for synthetic purposes.

Moreira, L. A., Murta, M. M., Gatto, C. C., Fagg, C. W., & dos Santos, M. L. (2015). Concise synthesis of N, N-dimethyltryptamine and 5-methoxy-N, N-dimethyltryptamine starting with bufotenine from Brazilian Anadenanthera ssp.. Natural product communications, 10(4), 581-584.
Link to full text

The use of ketamine as an antidepressant: a systematic review and meta-analysis

April 7, 2015 / Depressive Disorders, Ketamine, Papers, Psychology, Publications / By / ,

Abstract

Objective

The current meta-analysis examines the effects of ketamine infusion on depressive symptoms over time in major depressive disorder (MDD) and bipolar disorder (BD).

Methods

Following a systematic review of the literature, data were extracted from 21 studies (n  = 437 receiving ketamine) and analysed at four post-infusion time points (4 h, 24 h, 7 days and 12–14 days). The moderating effects of several factors were assessed including: repeat/single infusion, diagnosis, open-label/participant-blind infusion, pre–post/placebo-controlled design and the sex of patients.

Results

Effect sizes were significantly larger for repeat than single infusion at 4 h, 24 h and 7 days. For single infusion studies, effect sizes were large and significant at 4 h, 24 h and 7 days. The percentage of males was a predictor of antidepressant response at 7 days. Effect sizes for open-label and participant-blind infusions were not significantly different at any time point.

Conclusions

Single ketamine infusions elicit a significant antidepressant effect from 4 h to 7 days; the small number of studies at 12–14 days post infusion failed to reach significance. Results suggest a discrepancy in peak response time depending upon primary diagnosis — 24 h for MDD and 7 days for BD. The majority of published studies have used pre–post comparison; further placebo-controlled studies would help to clarify the effect of ketamine over time.

Coyle, C. M., & Laws, K. R. (2015). The use of ketamine as an antidepressant: a systematic review and meta‐analysis. Human Psychopharmacology: Clinical and Experimental, 30(3), 152-163. https://dx.doi.org/10.1002/hup.2475
Link to full text

Protecting the human rights of people who use psychedelics

April 1, 2015 / LSD, Mushrooms / Psilocybin, Papers, Psychology, Publications / By /

Summary

In a recent Comment Ben Sessa1 explained how the War on the Drugs worldwide has impeded development of psychiatric treatment with psychedelics such as LSD (lysergic acid diethylamide) and psilocybin (found in magic mushrooms). Prohibition also had negative outcomes for the millions of individuals who find it worthwhile to use psychedelics in various cultural settings outside of those in the clinic.

Krebs, T. S. (2015). Protecting the human rights of people who use psychedelics. The Lancet, 2(4), 294.295. http://dx.doi.org/10.1016/S2215-0366(15)00084-X
Link to full text

interested in becoming a trained psychedelic-assisted therapist?

Indigenous Talk: Fulni-ô Culture & Jurema - Online Event - Dec 12th

REGISTER NOW