OPEN Foundation

Author name: OPEN Foundation

Connectome-harmonic decomposition of human brain activity reveals dynamical repertoire re-organization under LSD

Abstract

Recent studies have started to elucidate the effects of lysergic acid diethylamide (LSD) on the human brain but the underlying dynamics are not yet fully understood. Here we used ‘connectome-harmonic decomposition’, a novel method to investigate the dynamical changes in brain states. We found that LSD alters the energy and the power of individual harmonic brain states in a frequency-selective manner. Remarkably, this leads to an expansion of the repertoire of active brain states, suggestive of a general re-organization of brain dynamics given the non-random increase in co-activation across frequencies. Interestingly, the frequency distribution of the active repertoire of brain states under LSD closely follows power-laws indicating a re-organization of the dynamics at the edge of criticality. Beyond the present findings, these methods open up for a better understanding of the complex brain dynamics in health and disease.
Atasoy, S., Roseman, L., Kaelen, M., Kringelbach, M. L., Deco, G., & Carhart-Harris, R. L. (2017). Connectome-harmonic decomposition of human brain activity reveals dynamical repertoire re-organization under LSD. Scientific reports7(1), 17661. 10.1038/s41598-017-17546-0
Link to full text

Connectome-harmonic decomposition of human brain activity reveals dynamical repertoire re-organization under LSD Read More »

Breaking the cycle of opioid use disorder with Ibogaine

Abstract

Ibogaine is an indole alkaloid that comes from the root of the West African shrub Tabernanthe iboga. Ibogaine has been used for centuries in spiritual celebrations, coming of age rituals, and healings among the Babongo and Mitsogo people of West Central Africa. In Africa today, approximately 2–3 million members of the Bwiti religion scattered in groups throughout the countries of the Gabon, Zaire, and the Cameroun take large doses for the “Bwiti initiation ritual”—a powerful “rebirth” ceremony that group members typically undergo before the commencement of their teenage years.
The discovery that ibogaine eliminates the signs and symptoms of opioid withdrawal and diminishes craving for opioids was first made in the 1960s by a group of self-treating individuals with heroin use disorder; a single oral dose administration of ibogaine was associated with a disruption of five addicted individual’s use of opiates for up to 6 months . An underground railroad of individuals in recovery helping others with addictions arose, using ibogaine to help people break their cycle of addiction to heroin, cocaine, and alcohol. Ibogaine is thought to enable individuals with opioid use disorder to transition to abstinence and establish a substance-free recovery through an ibogaine-induced experience that has personal meaning and/or other benefits. Ibogaine’s long-lasting metabolite noribogaine may reset brain circuits to block the intractable cravings and desire to use opioids that set the addiction relapse cycle into motion.
C. Mash, D. (2017). Breaking the cycle of opioid use disorder with Ibogaine. The American Journal of Drug and Alcohol Abuse, 1-3. 10.1080/00952990.2017.1357184
Link to full text 
 

Breaking the cycle of opioid use disorder with Ibogaine Read More »

Influence of Environmental Factors and Cultural Methods on the Content of N,N‑Dimethyltryptamine in Psychotria viridis (Rubiaceae)

Abstract

Psychotria viridis is one of the species that produces N,N-dimethyltryptamine. Its decoction together with other species, such as Banisteriopsis caapi, produces ayahuasca, a beverage used for ritualistic and medicinal purposes. The goal of this study was to understand how environmental factors and cultivation methods influenced the content of N,N-dimethyltryptamine in P. viridis. Over all four seasons, leaf samples were collected from 25 different locations in 14 Brazilian states, and Federal District. Environmental parameters, micro and macronutrients, plant characteristics, information on farming methods were correlated with N,N-dimethyltryptamine content, determined by gas chromatography coupled to mass spectrometry (GC-MS). Greatest effects on the N,N-dimethyltryptamine amount were associated with seasonality, altitude, latitude and biome type. A positive correlation between N and Mg content and N,N-dimethyltryptamine levels was statistically established. By regression analysis, the adequate foliar nutrient levels that would result in the concentration of N,N-dimethyltryptamine in cultivated plants similar to that of Amazonian P. viridis were equated.

Cavalcante, A. D., Cardoso, G. A., de Oliveira, F. L., Bearzoti, E., Okuma, A. A., Duartee, L. P., & Vieira-Filhof, S. A. Influence of Environmental Factors and Cultural Methods on the Content of N, N‑Dimethyltryptamine in Psychotria viridis (Rubiaceae).
Link to full text

Influence of Environmental Factors and Cultural Methods on the Content of N,N‑Dimethyltryptamine in Psychotria viridis (Rubiaceae) Read More »

The serotonin hallucinogen 5-MeO-DMT alters cortico-thalamic activity in freely moving mice: Regionally-selective involvement of 5-HT1A and 5-HT2A receptors

Abstract

5-MeO-DMT is a natural hallucinogen acting as serotonin 5-HT1A/5-HT2A receptor agonist. Its ability to evoke hallucinations could be used to study the neurobiology of psychotic symptoms and to identify new treatment targets. Moreover, recent studies revealed the therapeutic potential of serotonin hallucinogens in treating mood and anxiety disorders. Our previous results in anesthetized animals show that 5-MeO-DMT alters cortical activity via 5-HT1A and 5-HT2A receptors. Here, we examined 5-MeO-DMT effects on oscillatory activity in prefrontal (PFC) and visual (V1) cortices, and in mediodorsal thalamus (MD) of freely-moving wild-type (WT) and 5-HT2A-R knockout (KO2A) mice. We performed local field potential multi-recordings evaluating the power at different frequency bands and coherence between areas. We also examined the prevention of 5-MeO-DMT effects by the 5-HT1A-R antagonist WAY-100635. 5-MeO-DMT affected oscillatory activity more in cortical than in thalamic areas. More marked effects were observed in delta power in V1 of KO2A mice. 5-MeO-DMT increased beta band coherence between all examined areas. In KO2A mice, WAY100635 prevented most of 5-MeO-DMT effects on oscillatory activity. The present results indicate that hallucinatory activity of 5-MeO-DMT is likely mediated by simultaneous alteration of prefrontal and visual activities. The prevention of these effects by WAY-100635 in KO2A mice supports the potential usefulness of 5-HT1A receptor antagonists to treat visual hallucinations. 5-MeO-DMT effects on PFC theta activity and cortico-thalamic coherence may be related to its antidepressant activity.
Riga, M. S., Lladó-Pelfort, L., Artigas, F., & Celada, P. (2017). The serotonin hallucinogen 5-MeO-DMT alters cortico-thalamic activity in freely moving mice: Regionally-selective involvement of 5-HT 1A and 5-HT 2A receptors. Neuropharmacology. 10.1016/j.neuropharm.2017.11.049

Link to full text

The serotonin hallucinogen 5-MeO-DMT alters cortico-thalamic activity in freely moving mice: Regionally-selective involvement of 5-HT1A and 5-HT2A receptors Read More »

Acute effects of methylphenidate, modafinil and MDMA on negative emotion processing

Abstract

BACKGROUND:
Stimulants such as methylphenidate (MPH) and modafinil are frequently used as cognitive enhancers in healthy people, whereas 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is proposed to enhance mood and empathy in healthy subjects. However, comparative data on the effects of MPH and modafinil on negative emotions in healthy subjects have been widely missing. The aim of this study was to compare the acute effects of MPH and modafinil on the neural correlates of fearful face processing using MDMA as a positive control.
METHODS:
Using a double-blind within-subject placebo-controlled cross-over design, 60 mg MPH, 600 mg modafinil, and 125 mg MDMA were administrated to 22 healthy subjects, while performing an event-related fMRI task to assess brain activation in response to fearful faces. Negative mood states were assessed with the State-Trait Anxiety Inventory and subjective ratings.
RESULTS:
Relative to placebo, modafinil, but not MPH or MDMA, increased brain activation within a limbic-cortical-striatal-pallidal-thalamic circuit during fearful face processing. Modafinil but not MPH also increased amydgala responses to fearful faces compared with MDMA. Furthermore, activation in the middle and inferior frontal gyrus in response to fearful faces correlated positively with subjective feelings of fearfulness and depressiveness after modafinil administration.
CONCLUSIONS:
In spite of the cognitive enhancement effects of 600 mg modafinil in healthy people, potential adverse effects on emotion processing should be considered.
Schmidt, A., Müller, F., Dolder, P. C., Schmid, Y., Zanchi, D., Egloff, L., … & Borgwardt, S. (2017). Acute effects of methylphenidate, modafinil and MDMA on negative emotion processing. International Journal of Neuropsychopharmacology, pyx112. 10.1093/ijnp/pyx112
Link to full text

Acute effects of methylphenidate, modafinil and MDMA on negative emotion processing Read More »

Ketamine and pharmacological imaging: use of functional magnetic resonance imaging to evaluate mechanisms of action

Abstract

Ketamine has been used as a pharmacological model for schizophrenia as subanesthetic infusions have been shown to produce temporary schizophrenia-like symptoms in healthy humans. More recently, ketamine has emerged as a potential treatment for multiple psychiatric disorders, including treatment-resistant depression and suicidal ideation. However, the mechanisms underlying both the psychotomimetic and the therapeutic effects of ketamine remain poorly understood. This review provides an overview of what is known of the neural mechanisms underlying the effects of ketamine and details what functional MRI studies have yielded at a systems level focused on brain circuitry. Multiple analytic approaches show that ketamine exerts robust and consistent effects at the whole-brain level. These effects are highly conserved across human and nonhuman primates, validating the use of nonhuman primate models for further investigations with ketamine. Regional analysis of brain functional connectivity suggests that the therapeutic potential of ketamine may be derived from a strengthening of executive control circuitry, making it an intriguing candidate for the treatment of drug abuse. There are still important questions about the mechanism of action and the therapeutic potential of ketamine that can be addressed using appropriate functional neuroimaging techniques.
Maltbie, E. A., Kaundinya, G. S., & Howell, L. L. (2017). Ketamine and pharmacological imaging: use of functional magnetic resonance imaging to evaluate mechanisms of action. Behavioural Pharmacology28(8), 610-622. 10.1097/FBP.0000000000000354
Link to full text

Ketamine and pharmacological imaging: use of functional magnetic resonance imaging to evaluate mechanisms of action Read More »

Effects of harmaline on cell growth of human liver cancer through the p53/p21 and Fas/FasL signaling pathways

Abstract

The effects of harmaline on the viability and apoptosis of human liver carcinoma were investigated in vitro. HepG2 cells were treated with harmaline (0‑10 µM), and the proliferation and apoptosis of HepG2 cells were investigated using an MTT assay and flow cytometry, respectively. The protein expression of cellular tumor antigen p53 (p53), cyclin‑dependent kinase inhibitor 1 (p21), tumor necrosis factor receptor superfamily member 6 (Fas), Fas ligand (FasL) and caspase‑8 was subsequently measured using western blotting. In addition, an ELISA was used to analyze caspase‑8/3 activity. Harmaline significantly increased p53, p21, Fas and FasL protein expression in HepG2 cells. Additionally, treatment with harmaline significantly increased the expression of caspase‑8 and caspase‑8/3 activity. The results from the present study suggest that harmaline suppresses the viability, but induces the apoptosis, of human liver carcinoma cells through upregulation of the p53/p21 and Fas/FasL signaling pathways.
Xu, B., Li, M., Yu, Y., He, J., Hu, S., Pan, M., … & Zhu, J. (2018). Effects of harmaline on cell growth of human liver cancer through the p53/p21 and Fas/FasL signaling pathways. Oncology Letters15(2), 1931-1936. 10.3892/ol.2017.7495
Link to full text

Effects of harmaline on cell growth of human liver cancer through the p53/p21 and Fas/FasL signaling pathways Read More »

Psychedelics and reconsolidation of traumatic and appetitive maladaptive memories: focus on cannabinoids and ketamine

Abstract

Rationale

Clinical data with 3,4-methylenedioxymethamphetamine (MDMA) in post-traumatic stress disorder (PTSD) patients recently stimulated interest on the potential therapeutic use of psychedelics in disorders characterized by maladaptive memories, including substance use disorders (SUD). The rationale for the use of MDMA in PTSD and SUD is being extended to a broader beneficial “psychedelic effect,” which is supporting further clinical investigations, in spite of the lack of mechanistic hypothesis. Considering that the retrieval of emotional memories reactivates specific brain mechanisms vulnerable to inhibition, interference, or strengthening (i.e., the reconsolidation process), it was proposed that the ability to retrieve and change these maladaptive memories might be a novel intervention for PTSD and SUD. The mechanisms underlying MDMA effects indicate memory reconsolidation modulation as a hypothetical process underlying its efficacy.

Objective

Mechanistic and clinical studies with other two classes of psychedelic substances, namely cannabinoids and ketamine, are providing data in support of a potential use in PTSD and SUD based on the modulation of traumatic and appetitive memory reconsolidation, respectively. Here, we review preclinical and clinical data on cannabinoids and ketamine effects on biobehavioral processes related to the reconsolidation of maladaptive memories.

Results

We report the findings supporting (or not) the working hypothesis linking the potential therapeutic effect of these substances to the underlying reconsolidation process. We also proposed possible approaches for testing the use of these two classes of drugs within the current paradigm of reconsolidation memory inhibition.

Conclusions

Metaplasticity may be the process in common between cannabinoids and ketamine/ketamine-like substance effects on the mediation and potential manipulation of maladaptive memories.

Fattore, L., Piva, A., Zanda, M. T., Fumagalli, G., & Chiamulera, C. (2017). Psychedelics and reconsolidation of traumatic and appetitive maladaptive memories: focus on cannabinoids and ketamine. Psychopharmacology, 1-13. 10.1007/s00213-017-4793-4
Link to full text

Psychedelics and reconsolidation of traumatic and appetitive maladaptive memories: focus on cannabinoids and ketamine Read More »

A regulatory perspective on the evaluation of hallucinogen drugs for human use

Abstract

In recent years, there is renewed interest in the study of various hallucinogens for their potential therapeutic effects. In the United States of America (USA), the abuse potential assessment of a drug is carried out as part of the general safety and efficacy evaluation of a drug. Additionally, the abuse potential assessment is taken under consideration in determining if a drug needs to be subject to controls to minimize the abuse of the drug once on the market. This assessment is conducted for all new drugs with central nervous system (CNS) activity, that are chemically or pharmacologically similar to other drugs with known abuse potential, or drugs that produce psychoactive effects predictive of abuse, such as euphoria and hallucinations. This paper describes the regulatory framework for evaluating the abuse potential of new drugs, with emphasis on hallucinogens. The paper discusses the role of the United States Food and Drug Administration (FDA) in the evaluation of the abuse potential of drugs and its role in drug control, and provides an overview of the controlled status of hallucinogens and the requirements to conduct research with Schedule I substances in the USA.

Calderon, S. N., Hunt, J., & Klein, M. (2017). A regulatory perspective on the evaluation of hallucinogen drugs for human use. Neuropharmacology. 10.1016/j.neuropharm.2017.11.028
Link to full text

A regulatory perspective on the evaluation of hallucinogen drugs for human use Read More »

Psycholytic Therapy: Lessons from Low-Moderate Dose Psilocybin Research - Online Event - July 17