Ketamine may alleviate treatment-resistant depression (TRD) primarily through glutamatergic modulation, with downstream dopaminergic activation. Iron plays an important role in monoaminergic metabolism, that is also implicated in the pathophysiology of TRD. Both Quantitative Susceptibility Mapping (QSM) and Effective Transverse Relaxation Rate (R2*) mapping can determine the extent of iron...
Introduction: While the rapid and robust effects of ketamine on depressive symptoms in treatment-resistant depression (TRD) have been demonstrated, the influence of ketamine treatment on cognitive function has not yet been fully elucidated. We aimed to evaluate the effects of ketamine treatment on cognitive function as part of a study that investigated the efficacy of repeated ketamine...
Approximately 30% of patients with depression suffer from treatment-resistant depression (TRD). Ketamine has shown antidepressant efficacy for TRD. While glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) has been demonstrated to play crucial roles in the process of pharmacological action of ketamine in experimental animals, it remains elusive how ketamine exhibits...
Psilocybin, a classic psychedelic compound, has garnered renewed interest as a potential treatment for various psychiatric disorders. This review provides a comprehensive overview of psilocybin's history, recent clinical evidence, ongoing clinical trials, neuroimaging findings, and regulations. Historically used in spiritual and healing rituals, psilocybin was in the early 1970s subjected to...
Approximately 30 % of patients with treatment-resistant depression (TRD) respond to ketamine; however, no replicable predictors of response have been reported. The imbalance between excitatory and inhibitory neurotransmissions may be implicated in the mechanism of action of ketamine. This study aimed to evaluate whether the ratio of glutamate and glutamine (Glx) to GABA levels at baseline in...
Abstract Background Whereas ketamine has displayed robust antidepressant effects in treatment-resistant depression (TRD) (Han et al., 2016), only 30-40% of patients with TRD respond to ketamine therapy (Wilkinson et al., 2018; Sakurai et al., 2020). Several postmortem studies have shown decreased myelination in patients with depression (Hamidi, Drevets and Price, 2004; Altshuler et al., 2010),...
Although the antidepressant effect of ketamine on treatment-resistant depression (TRD) has been frequently reported in North American and European countries, evidence is scarce among the Asian population. We aimed to evaluate the efficacy and safety of intravenous ketamine in Japanese patients with TRD. In this double-blind randomized placebo-controlled trial, 34 Japanese patients with TRD were...
Abstract Introduction The therapeutic potential of psychedelics for various mental disorders has gained significant interest. Previous studies have highlighted that psychedelics induce psychoactive effects, including challenging aspects of experiences. These experiences are assessed using the Challenging Experience Questionnaire (CEQ), yet its Japanese version has been unavailable. This study...
Abstract Introduction Psychedelics have garnered increased attention as potential therapeutic options for various mental illnesses. Previous studies reported that psychedelics cause psychoactive effects through mystical experiences induced by these substances, including an altered state of consciousness. While this phenomenon is commonly assessed by the Mystical Experiences Questionnaire...
Abstract Aim Psychedelics have recently gained attention as potential therapeutic agents for various psychiatric disorders. Previous research has highlighted that a diminished sense of self, commonly termed “ego‐dissolution” is a pivotal feature of the psychedelic‐induced state. While the Ego‐Dissolution Inventory (EDI) is a widely acknowledged instrument for measuring this phenomenon, no...
Abstract Introduction There is an imminent need for faster-acting and more effective antidepressants beyond the monoaminergic hypothesis. Methods We systematically searched the US Clinical Trials registry for antidepressant compounds with completed phase II and III trials. Compounds that demonstrated significant superiority over placebo in the primary outcome measure in the latest phase of...