OPEN Foundation

Anxiety disorders / PTSD

In vivo effects of 3,4-methylenedioxymethamphetamine (MDMA) and its deuterated form in rodents: Drug discrimination and thermoregulation.

Abstract

BACKGROUND:

Recent clinical studies support the use of 3,4-methylenedioxymethamphetamine (MDMA) as an adjunct treatment for posttraumatic stress disorder (PTSD). Despite these promising findings, MDMA administration in controlled settings can increase blood pressure, heart rate, and body temperature. Previous studies indicate thatO-demethylated metabolites of MDMA contribute to its adverse effects. As such, limiting the conversion of MDMA to reactive metabolites may mitigate some of its adverse effects and potentially improve its safety profile for therapeutic use.

METHODS:

We compared the interoceptive and hyperthermic effects of a deuterium-substituted form of MDMA (d2-MDMA) to MDMA using rodent drug discrimination and biotelemetry procedures, respectively.

RESULTS:

Compared to MDMA, d2-MDMA produced full substitution for a 1.5 mg/kg MDMA training stimulus with equal potency and effectiveness in the drug discrimination experiment. In addition, d2-MDMA produced increases in body temperature that were shorter-lasting and of lower magnitude compared to equivalent doses of MDMA. Last, d2-MDMA and MDMA were equally effective in reversing the hypothermic effects of the selective 5-HT2A/2C antagonist ketanserin.

CONCLUSION:

These findings indicate that deuterium substitution of hydrogen at the methylenedioxy ring moiety does not impact MDMA’s interoceptive effects, and compared to MDMA, d2-MDMA has less potential for producing hyperthermic effects and likely has similar pharmacodynamic properties. Given that d2-MDMA produces less adverse effects than MDMA, but retains similar desirable effects that are thought to relate to the effective treatment of PTSD, additional investigations into its effects on cardiovascular functioning and pharmacokinetic properties are warranted.

Berquist, M. D., Leth-Petersen, S., Kristensen, J. L., & Fantegrossi, W. E. (2020). In vivo effects of 3, 4-methylenedioxymethamphetamine (MDMA) and its deuterated form in rodents: drug discrimination and thermoregulation. Drug and Alcohol Dependence, 107850., 10.1016/j.drugalcdep.2020.107850
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A Dangerous Method? Psychedelic Therapy at Modum Bad, Norway, 1961-76

Abstract

After many years of disregard, the use of psychedelic drugs in psychiatric treatment has re-emerged in recent years. The prospect that psychedelics may again be integrated into mainstream psychiatry has aroused interest in long-forgotten research and experience from the previous phase of psychedelic therapy, which lasted from the late 1940s to the 1970s. This article will discuss one large-scale psychedelic therapy programme at Modum Bad Nervesanatorium, a psychiatric clinic which treated 379 inpatients with psychedelic drugs during the years 1961-76. The psychiatrists there initially regarded the psychedelic treatment as efficacious and without serious negative reactions, but reports of long-term harm have since surfaced. This article discusses how insights from Modum Bad might benefit the new generation of psychedelic treatment efforts.
Johnstad, P. G. (2020). A dangerous method? Psychedelic therapy at Modum Bad, Norway, 1961–76. History of Psychiatry31(2), 217-226., https://doi.org/10.1177%2F0957154X19894537
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Long-term follow-up of psilocybin-assisted psychotherapy for psychiatric and existential distress in patients with life-threatening cancer.

Abstract

BACKGROUND:
A recently published randomized controlled trial compared single-dose psilocybin with single-dose niacin in conjunction with psychotherapy in participants with cancer-related psychiatric distress. Results suggested that psilocybin-assisted psychotherapy facilitated improvements in psychiatric and existential distress, quality of life, and spiritual well-being up to seven weeks prior to the crossover. At the 6.5-month follow-up, after the crossover, 60-80% of participants continued to meet criteria for clinically significant antidepressant or anxiolytic responses.
METHODS:
The present study is a long-term within-subjects follow-up analysis of self-reported symptomatology involving a subset of participants that completed the parent trial. All 16 participants who were still alive were contacted, and 15 participants agreed to participate at an average of 3.2 and 4.5 years following psilocybin administration.
RESULTS:
Reductions in anxiety, depression, hopelessness, demoralization, and death anxiety were sustained at the first and second follow-ups. Within-group effect sizes were large. At the second (4.5 year) follow-up approximately 60-80% of participants met criteria for clinically significant antidepressant or anxiolytic responses. Participants overwhelmingly (71-100%) attributed positive life changes to the psilocybin-assisted therapy experience and rated it among the most personally meaningful and spiritually significant experiences of their lives.
CONCLUSION:
These findings suggest that psilocybin-assisted psychotherapy holds promise in promoting long-term relief from cancer-related psychiatric distress. Limited conclusions, however, can be drawn regarding the efficacy of this therapy due to the crossover design of the parent study. Nonetheless, the present study adds to the emerging literature base suggesting that psilocybin-facilitated therapy may enhance the psychological, emotional, and spiritual well-being of patients with life-threatening cancer.
Agin-Liebes, G. I., Malone, T., Yalch, M. M., Mennenga, S. E., Ponté, K. L., Guss, J., … & Ross, S. (2020). Long-term follow-up of psilocybin-assisted psychotherapy for psychiatric and existential distress in patients with life-threatening cancer. Journal of Psychopharmacology, 0269881119897615., https://doi.org/10.1177%2F0269881119897615
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Anxiety-like behavior induced by salicylate depends on age and can be prevented by a single dose of 5-MeO-DMT

Abstract

Salicylate intoxication is a cause of tinnitus and comorbidly associated with anxiety in humans. In a previous work, we showed that salicylate induces anxiety-like behavior and hippocampal type 2 theta oscillations (theta2) in mice. Here we investigate if the anxiogenic effect of salicylate is dependent on age and previous tinnitus experience. We also tested whether a single dose of DMT can prevent this effect. Using microwire electrode arrays, we recorded local field potential in young (4-5- month-old) and old (11-13-month-old) mice to study the electrophysiological effect of tinnitus in the ventral hippocampus (vHipp) and medial prefrontal cortex (mPFC) in an open field arena and elevated plus maze 1h after salicylate (300mg/kg) injection. We found that anxiety-like behavior and increase in theta2 oscillations (4-6 Hz), following salicylate pre-treatment, only occurs in young (normal hearing) mice. We also show that theta2 and slow gamma oscillations increase in the vHipp and mPFC in a complementary manner during anxiety tests in the presence of salicylate. Finally, we show that pre-treating mice with a single dose of the hallucinogenic 5-MeO-DMT prevents anxiety-like behavior and the increase in theta2 and slow gamma oscillations after salicylate injection in normal hearing young mice. This work further support the hypothesis that anxiety-like behavior after salicylate injection is triggered by tinnitus and require normal hearing. Moreover, our results show that hallucinogenic compounds can be effective in treating tinnitus-related anxiety.

Winne, J., Boerner, B. C., Malfatti, T., Brisa, E., Doerl, J., Nogueira, I., Leão, K. E., & Leão, R. N. (2020). Anxiety-like behavior induced by salicylate depends on age and can be prevented by a single dose of 5-MeO-DMT. Experimental neurology, 326, 113175. https://doi.org/10.1016/j.expneurol.2020.113175

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The experimental effects of psilocybin on symptoms of anxiety and depression: A meta-analysis.

Abstract

The current meta-analysis examined the effects of psilocybin in combination with behavioral interventions on anxiety and depression in samples with elevated symptoms. Across four studies (one uncontrolled; three randomized, placebo-controlled; N = 117), within-group pre-post and pre-follow-up effects on anxiety and depression were large (Hedges’ gs=1.16 to 1.47) and statistically significant. Across three placebo-controlled studies, pre-post placebo-controlled effects were also large (gs = 0.82 to 0.83) and statistically significant. No serious adverse events were reported. Limitations include the small number of studies and risk for bias within studies. Results tentatively support future research on psilocybin for the treatment of anxiety and depression.

Goldberg, S. B., Pace, B. T., Nicholas, C. R., Raison, C. L., & Hutson, P. R. (2020). The experimental effects of psilocybin on symptoms of anxiety and depression: A meta-analysis. Psychiatry Research, 112749., https://doi.org/10.1016/j.psychres.2020.112749
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Preliminary Report on the Effects of a Low Dose of LSD on Resting-State Amygdala Functional Connectivity.

Abstract

BACKGROUND:
The practice of “microdosing,” or the use of repeated, very low doses of lysergic acid diethylamide (LSD) to improve mood or cognition, has received considerable public attention, but empirical studies are lacking. Controlled studies are needed to investigate both the therapeutic potential and the neurobiological underpinnings of this pharmacologic treatment.
METHODS:
The present study was designed to examine the effects of a single low dose of LSD (13 μg) versus placebo on resting-state functional connectivity and cerebral blood flow in healthy young adults. Twenty men and women, 18 to 35 years old, participated in 2 functional magnetic resonance imaging scanning sessions in which they received placebo or LSD under double-blind conditions. During each session, the participants completed drug effect and mood questionnaires, and physiological measures were recorded. During expected peak drug effect, they underwent resting-state blood oxygen level-dependent and arterial spin labeling scans. Cerebral blood flow as well as amygdala and thalamic connectivity were analyzed.
RESULTS:
LSD increased amygdala seed-based connectivity with the right angular gyrus, right middle frontal gyrus, and the cerebellum, and decreased amygdala connectivity with the left and right postcentral gyrus and the superior temporal gyrus. This low dose of LSD had weak and variable effects on mood, but its effects on positive mood were positively correlated with the increase in amygdala-middle frontal gyrus connectivity strength.
CONCLUSIONS:
These preliminary findings show that a very low dose of LSD, which produces negligible subjective changes, alters brain connectivity in limbic circuits. Additional studies, especially with repeated dosing, will reveal whether these neural changes are related to the drug’s purported antidepressant effect.

Bershad, A. K., Preller, K. H., Lee, R., Keedy, S., Wren-Jarvis, J., Bremmer, M. P., & de Wit, H. (2019). Preliminary report on the effects of a low dose of LSD on resting state amygdalar functional connectivity. Biological Psychiatry: Cognitive Neuroscience and Neuroimaging., https://doi.org/10.1016/j.bpsc.2019.12.007
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From Egoism to Ecoism: Psychedelics Increase Nature Relatedness in a State-Mediated and Context-Dependent Manner.

Abstract

(1) Background: There appears to be a growing disconnection between humans and their natural environments which has been linked to poor mental health and ecological destruction. Previous research suggests that individual levels of nature relatedness can be increased through the use of classical psychedelic compounds, although a causal link between psychedelic use and nature relatedness has not yet been established. (2) Methods: Using correlations and generalized linear mixed regression modelling, we investigated the association between psychedelic use and nature relatedness in a prospective online study. Individuals planning to use a psychedelic received questionnaires 1 week before (N = 654), plus one day, 2 weeks, 4 weeks, and 2 years after a psychedelic experience. (3) Results: The frequency of lifetime psychedelic use was positively correlated with nature relatedness at baseline. Nature relatedness was significantly increased 2 weeks, 4 weeks and 2 years after the psychedelic experience. This increase was positively correlated with concomitant increases in psychological well-being and was dependent on the extent of ego-dissolution and the perceived influence of natural surroundings during the acute psychedelic state. (4) Conclusions: The here presented evidence for a context- and state-dependent causal effect of psychedelic use on nature relatedness bears relevance for psychedelic treatment models in mental health and, in the face of the current ecological crisis, planetary health.
Kettner, H., Gandy, S., Haijen, E. C., & Carhart-Harris, R. L. (2019). From Egoism to Ecoism: Psychedelics Increase Nature Relatedness in a State-Mediated and Context-Dependent Manner. International Journal of Environmental Research and Public Health16(24), 5147., https://doi.org/10.3390/ijerph16245147
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Neurotrophic mechanisms of psychedelic therapy

Abstract

Psychedelic drugs, often referred to as hallucinogens, are quite distinct from other classes of psychotropic drugs. Although the subjective and behavioral effects they induce are quite dramatic, they possess little addictive potential when compared to nicotine, alcohol or opiates. Since the discovery of ketamine antidepressant effects, there has been growing interest for these molecules. Serotonergic psychedelics such as psilocybin and lysergic acid diethylamide (LSD) are gaining attention as potential treatments for depression and addiction, similarly to 3,4-methylenedioxymethamphetamine (MDMA) for post-traumatic stress disorder (PTSD), and ibogaine for addiction. Although they possess distinct pharmacological profiles, their kinetics of action are quite similar: the therapeutic effects are felt within the hours following administration, and last well beyond drug elimination by the organism. This strongly suggests the induction of neurogenic and plastic mechanisms, including the involvement of trophic factors. This review will explore the literature dealing with the effects of psychedelics on neurotrophins, as well as the plastic adaptations that they induce, in an attempt to understand their surprising therapeutic potential. We will show that although ketamine and serotonergic psychedelics have affinity for very different receptors (NMDA, 5-HT2A), they ultimately initiate similar plastic adaptations in the prefrontal cortex through the involvement of the brain-derived neurotrophic factor (BDNF). We will see that although MDMA uses the same receptors as serotonergic psychedelics to alleviate PTSD symptoms, its effect on BDNF levels seem paradoxical and quite different. Finally, we show how ibogaine could exert its anti-addictive properties through a completely different neurotrophic factor than other psychedelic drugs, the glial cell line-derived neurotrophic factor (GDNF). While the current literature concerning the psychiatric applications of psychedelic therapy is encouraging, it remains to be determined whether their benefits could be obtained without their psychotomimetic effects, or concerns over potential toxicity.
Corne, R., & Mongeau, R. (2019). Neurotrophic mechanisms of psychedelic therapy. Biologie aujourd’hui213(3-4), 121., https://doi.org/10.1051/jbio/2019015
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Therapeutic use of serotoninergic hallucinogens: A review of the evidence and of the biological and psychological mechanisms.

Abstract

Serotoninergic hallucinogens include drugs such as lysergic acid diethylamide (LSD), dimethyltryptamine (DMT) and psilocybin. Recent trials with single/few doses of these compounds show that they induce rapid and sustained antidepressive, anxiolytic, and antiaddictive effects. These effects are also observed in religious groups using the DMT-containing brew ayahuasca. The agonist action of these substances on 5-HT2A receptors expressed in frontal and limbic areas increase glutamatergic transmission and neuroplasticity. These neurochemical effects are associated with acute alterations on self-perception and increases in introspection and positive mood, and with subacute and long-term decreases in psychiatric symptoms, increases in some personality traits such as openness, improvements in emotional processing, and increases in empathy. These are preliminary but promising results that should be further explored in controlled trials with larger sample sizes, especially considering that these compounds could be beneficial in the treatment of treatment-resistant psychiatric disorders.
dos Santos, R. G., & Hallak, J. E. C. (2019). Therapeutic use of serotoninergic hallucinogens: a review of the evidence and of the biological and psychological mechanisms. Neuroscience & Biobehavioral Reviews., https://doi.org/10.1016/j.neubiorev.2019.12.001
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Embedding existential psychology within psychedelic science: reduced death anxiety as a mediator of the therapeutic effects of psychedelics.

Abstract

Psychedelic therapies can engender enduring improvements in psychological well-being. However, relatively little is known about the psychological mechanisms through which the salutary effects of psychedelics emerge. Through integrating extant research on psychedelics with contemporary existential psychology, we present a novel hypothesis that reduced death anxiety may be a key mechanism underpinning the therapeutic effects of psychedelics. In developing this hypothesis, we also provide a complementary review of mechanisms through which psychedelics may reduce death anxiety. We conclude that an awareness of the role of death anxiety in psychopathology has the potential to guide future research into psychedelic therapies.

Moreton, S. G., Szalla, L., Menzies, R. E., & Arena, A. F. (2019). Embedding existential psychology within psychedelic science: reduced death anxiety as a mediator of the therapeutic effects of psychedelics. 29, 1-12., https://doi.org/10.1007/s00213-019-05391-0
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22 May - Delivering Effective Psychedelic Clinical Trials

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