OPEN Foundation

Day: 6 December 2016

Psilocybin: promising results in double-blind trials require confirmation by real-world evidence

Breckenridge, A., & Grobbee, D. E. (2016). Psilocybin: promising results in double-blind trials require confirmation by real-world evidence. Journal of psychopharmacology (Oxford, England), 30(12), 1218. 10.1177/0269881116675784
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Psilocybin for depression and anxiety associated with life-threatening illnesses

Abstract

Life-threatening and terminal illnesses are accompanied by substantial stressors that encumber both patients and their families. Faced with a life-threatening diagnosis such as late-stage cancer, these factors can compound the existential crisis of impending mortality and produce or exacerbate major depressive and anxiety symptoms (Silverstone, 1990; Vergo et al., 2016). Addressing depression and anxiety in the unique context of life-threatening illnesses has been a significant problem for palliative psychiatric care. In this regard, two recent studies suggest that the one-time use of the naturally derived psychoactive compound psilocybin could have the potential to alleviate these symptoms for up to six months.

McCorvy, J. D., Olsen, R. H., & Roth, B. L. (2016). Psilocybin for depression and anxiety associated with life-threatening illnesses. Journal of psychopharmacology (Oxford, England), 30(12), 1209. 10.1177/0269881116675771
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Antisuicidal Response Following Ketamine Infusion Is Associated With Decreased Nighttime Wakefulness in Major Depressive Disorder and Bipolar Disorder

Abstract

OBJECTIVE: Insomnia and disrupted sleep are associated with increased risk of suicide. The N-methyl-D-aspartate antagonist ketamine has been associated with reduced suicidal thoughts, but the mechanism of action is unknown. This study sought to evaluate differences in nocturnal wakefulness in depressed individuals who did and did not have an antisuicidal response to ketamine.

METHODS: Thirty-four participants with baseline suicidal ideation diagnosed with either DSM-IV major depressive disorder (n = 23) or bipolar depression (n = 11) between 2006 and 2013 completed nighttime electroencephalography (EEG) the night before and the night after a single ketamine infusion (0.5 mg/kg over 40 minutes). Suicidal ideation was assessed at baseline and the morning after ketamine infusion via several measures, including the Hamilton Depression Rating Scale suicide item, the suicide item of the Montgomery-Asberg Depression Rating Scale, and the first 5 items of the Scale for Suicide Ideation. A generalized linear mixed model evaluated differences in nocturnal wakefulness, as verified by EEG, between those who had an antisuicidal response to ketamine and those who did not, controlling for baseline nocturnal wakefulness. Results were also compared to the sleep of healthy controls (n = 22).

RESULTS: After analyses adjusted for baseline sleep, participants with an antisuicidal response to ketamine showed significantly reduced nocturnal wakefulness the night after ketamine infusion compared to those without an antisuicidal response (F₁,₂₂ = 5.04, P = .04). Level of nocturnal wakefulness after antisuicidal response to ketamine did not differ significantly from nocturnal wakefulness in the control sample but did differ at a trend level (F₁,₄₀ = 3.15, P = .08).

CONCLUSIONS: Reductions in wakefulness following ketamine may point to a biological mechanism underlying the effect of ketamine on suicidal ideation.

Vande Voort, J. L., Ballard, E. D., Luckenbaugh, D. A., Bernert, R. A., Richards, E. M., Niciu, M. J., … & Zarate, C. A. (2016). Antisuicidal response following ketamine infusion is associated with decreased nighttime wakefulness in major depressive disorder and bipolar disorder. Journal of clinical psychiatry. 10.4088/JCP.15m10440
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Harmine stimulates proliferation of human neural progenitors

Abstract

Harmine is the β-carboline alkaloid with the highest concentration in the psychotropic plant decoction Ayahuasca. In rodents, classical antidepressants reverse the symptoms of depression by stimulating neuronal proliferation. It has been shown that Ayahuasca presents antidepressant effects in patients with depressive disorder. In the present study, we investigated the effects of harmine in cell cultures containing human neural progenitor cells (hNPCs, 97% nestin-positive) derived from pluripotent stem cells. After 4 days of treatment, the pool of proliferating hNPCs increased by 71.5%. Harmine has been reported as a potent inhibitor of the dual specificity tyrosine-phosphorylation-regulated kinase (DYRK1A), which regulates cell proliferation and brain development. We tested the effect of analogs of harmine, an inhibitor of DYRK1A (INDY), and an irreversible selective inhibitor of monoamine oxidase (MAO) but not DYRK1A (pargyline). INDY but not pargyline induced proliferation of hNPCs similarly to harmine, suggesting that inhibition of DYRK1A is a possible mechanism to explain harmine effects upon the proliferation of hNPCs. Our findings show that harmine enhances proliferation of hNPCs and suggest that inhibition of DYRK1A may explain its effects upon proliferation in vitro and antidepressant effects in vivo.

Dakic, V., de Moraes Maciel, R., Drummond, H., Nascimento, J. M., Trindade, P., & Rehen, S. K. (2016). Harmine stimulates proliferation of human neural progenitors. PeerJ, 4, e2727. 10.7717/peerj.2727
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