-
Clinical Psychopharmacology and... Feb 2024Psilocybin is a classical psychedelic which has been utilised for healing purposes for millenia. However, with its classification as a Schedule I substance, research... (Review)
Review
Psilocybin is a classical psychedelic which has been utilised for healing purposes for millenia. However, with its classification as a Schedule I substance, research into this compound is scarce with few FDA-approved clinical studies. Despite this, profound findings into its antidepressant effects (largely through its action on 5-HT1a receptors) in mental illnesses such as major depressive disorder have rapidly increased interest back into their potential therapeutic benefits. This systematic review provides an analysis of the studies examining the clinical use of psilocybin for major depressive disorder. In total 6 studies were selected, including 319 participants, with half being randomised controlled trials and half open label trials. In every study psychological support was included as an integral part of the treatment. It was found that every study significantly favoured the use of psilocybin in reducing depressive symptoms, with few side effects. This gives psilocybin an advantage over commonly prescribed selective serotonin reuptake inhibitors (SSRIs), which carry more risk and cause more adverse effects. This drug therefore shows promise for being used as a clinical treatment for major depressive disorder, however future research should develop a paradigm for its use, with the timing of sessions and type of psychological support specified to allow for more precise analysis of the clinical effects of the drug. Additionally, more studies into its clinical efficacy are needed for appropriate detection of any publication bias. With this, psilocybin could prove to be revolutionary in treating depression and become an alternative medication to SSRIs.
PubMed: 38247407
DOI: 10.9758/cpn.23.1120 -
Frontiers in Pharmacology 2023Cancer is a neoplastic transformation that affects tissue. Among the many complications associated with cancer treatment, managing the distressing side effects of...
Cancer is a neoplastic transformation that affects tissue. Among the many complications associated with cancer treatment, managing the distressing side effects of chemotherapy-induced nausea and vomiting (CINV) is of main concern. Ondansetron is a selective serotonin 5-HT3 receptor antagonist that has emerged as an essential medication against CINV in adult cancer patients. Ondansetron efficacy and tolerability have made it a primary medication in CINV prophylaxis and treatment regimens. The study aims to offer a detailed overview of ondansetron's effectiveness, safety, and impact on patients' lives, ultimately contributing to the ongoing research to enhance the quality of cancer care. On 4 September 2023, a search was conducted of the ClinicalTrials.gov database using the search terms "cancer," "ondansetron," and "Zofran." Inclusion and exclusion criteria were defined to select relevant clinical trials. Included trials were completed with results and interventional studies that assessed the preventive effects of ondansetron on CINV in adult cancer patients. A total of 23 clinical trials were identified, with only 13 of them focusing on investigating the preventive effects of ondansetron on CINV in adult cancer patients. The collective findings from these trials showed an effective management of CINV using ondansetron. Through a comprehensive overview of clinical trials, the use of ondansetron in adult cancer patients represents a significant improvement in CINV management.
PubMed: 38074143
DOI: 10.3389/fphar.2023.1310455 -
Scientific Reports Nov 2023Obsessive-compulsive disorder (OCD) is the fourth most common mental disorder, and selective serotonin reuptake inhibitors (SSRIs) are the cornerstone of its... (Meta-Analysis)
Meta-Analysis
Efficacy and safety of 5-hydroxytryptamine-3 (5-HT3) receptor antagonists in augmentation with selective serotonin reuptake inhibitors (SSRIs) in the treatment of moderate to severe obsessive-compulsive disorder: a systematic review and meta-analysis of randomized clinical trials.
Obsessive-compulsive disorder (OCD) is the fourth most common mental disorder, and selective serotonin reuptake inhibitors (SSRIs) are the cornerstone of its pharmacological treatment. About 40-60% of the cases are treatment-refractory, and this makes searching for second-line treatment necessary. 5-Hydroxytryptamine-3 (5-HT3) antagonists are among the many medications that have been used in augmentation with SSRIs. In this systematic review and meta-analysis, we assessed the efficacy and safety of 5-HT3 receptor antagonists in augmentation with SSRIs in treating moderate to severe OCD. We searched PubMed, Web of Science, Scopus, Cochrane library, and Google Scholar for relevant trials published up to December 2022. The effect size was the mean difference in Yale-Brown obsessive compulsive scale (Y-BOCS) scores before and after receiving 5-HT3 receptor antagonist drugs in augmentation with SSRIs in moderate to severe OCD patients. We included 6 randomized-controlled trails (RCTs) with 334 patients assessing the effect of the augmentation of SSRIs with ondansetron, granisetron, and tropisetron on treating moderate to severe OCD. Our results were in favor of the experimental group in total (Z = 8.37, P < 0.00001), in the compulsion subgroup (Z = 5.22, P < 0.00001), and in the obsession subgroup (Z = 8.33, P < 0.00001). They are well-tolerated, and have mild side effects and do not result in withdrawal. Augmentation of 5-HT3 antagonists with SSRIs can be beneficial in treating moderate to severe OCD. Further multi-center trials under adequate conditions in longer periods are needed to help come up with a comprehensive action plan.
Topics: Humans; Selective Serotonin Reuptake Inhibitors; Serotonin; Receptors, Serotonin, 5-HT3; Treatment Outcome; Randomized Controlled Trials as Topic; Obsessive-Compulsive Disorder; Drug Therapy, Combination
PubMed: 38012263
DOI: 10.1038/s41598-023-47931-x -
CNS Drugs Dec 2023The renewed interest in psychedelic research provides growing evidence of potentially unique effects on various aspects of reward processing systems. Using the Research...
BACKGROUND AND OBJECTIVES
The renewed interest in psychedelic research provides growing evidence of potentially unique effects on various aspects of reward processing systems. Using the Research Domain Criteria (RDoC) framework, as proposed by the National Institute of Mental Health, we aim to synthesize the existing literature concerning the impact of lysergic acid diethylamide (LSD) on the RDoC's Positive Valence Systems (PVS) domain, and to identify potential avenues for further research.
METHODS
Two LSD-related terms (lysergic acid diethylamide and LSD) and 13 PVS-related terms (reward, happiness, bliss, motivation, reinforcement learning, operant, conditioning, satisfaction, decision making, habit, valence, affect, mood) were used to search electronic databases such as PubMed, Scopus, PsychINFO, and Web of Science for relevant articles. A manual search of the reference list resulted in nine additional articles. After screening, articles and data were evaluated and included based on their relevance to the objective of investigating the effects of LSD on the PVS. Articles and data were excluded if they did not provide information about the PVS, were observational in nature, lacked comparators or reference groups, or were duplicates. A risk of bias assessment was performed using the National Toxicology Program's Office of Health Assessment and Translation (NTP OHAT) risk of bias (RoB) tool. Data from the included articles were collected and structured based on the RDoC bio-behavioral matrix, specifically focusing on the PVS domain and its three constituent constructs: reward responsiveness, reward learning, and reward valuation.
RESULTS
We reviewed 28 clinical studies with 477 participants. Lysergic acid diethylamide, assessed at self-report (23 studies), molecular (5 studies), circuit (4 studies), and paradigm (3 studies) levels, exhibited dose-dependent mood improvement (20 short-term and 3 long-term studies). The subjective and neural effects of LSD were linked to the 5-HT receptor (molecular). Animal studies (14 studies) suggested LSD could mildly reinforce conditioned place preference without aversion and reduce responsiveness to other rewards. Findings on reward learning were inconsistent but hinted at potential associative learning enhancements. Reward valuation measures indicated potential reductions in effort expenditure for other reinforcers.
CONCLUSION
Our findings are consistent with our previous work, which indicated classical psychedelics, primarily serotonin 2A receptor agonists, enhanced reward responsiveness in healthy individuals and patient populations. Lysergic acid diethylamide exhibits a unique profile in the reward learning and valuation constructs. Using the RDoC-based framework, we identified areas for future research, enhancing our understanding of the impact of LSD on reward processing. However, applying RDoC to psychedelic research faces limitations due to diverse study designs that were not initially RDoC-oriented. Limitations include subjective outcome measure selection aligned with RDoC constructs and potential bias in synthesizing varied studies. Additionally, some human studies were open-label, introducing potential bias compared to randomized, blinded studies.
Topics: Animals; Humans; Hallucinogens; Lysergic Acid Diethylamide; Serotonin Receptor Agonists; Affect; Self Report
PubMed: 37999867
DOI: 10.1007/s40263-023-01044-1 -
The 5-HT7 receptor system as a treatment target for mood and anxiety disorders: A systematic review.Journal of Psychopharmacology (Oxford,... Dec 2023Preclinical animal and preliminary human studies indicate that 5-HT7 antagonists have the potential as a new treatment approach for mood and anxiety disorders. In this... (Review)
Review
BACKGROUND
Preclinical animal and preliminary human studies indicate that 5-HT7 antagonists have the potential as a new treatment approach for mood and anxiety disorders. In this systematic review, we aimed to review the relationship between the 5-HT7 receptor system and mood and anxiety disorders, and to explore the pharmacology and therapeutic potential of medications that target the 5-HT7 receptor for their treatment.
METHODS
Medline, Cochrane Library, EMBASE, PsycINFO databases, the National Institute of Health website Clinicaltrials.gov, controlled-trials.com, and relevant grey literature were used to search for original research articles, and reference lists of included articles were then hand searched.
RESULTS
Sixty-four studies were included in the review: 52 animal studies and 12 human studies. Studies used a variety of preclinical paradigms and questionnaires to assess change in mood, and few studies examined sleep or cognition. Forty-four out of 47 (44/47) preclinical 5-HT7 modulation studies identified potential antidepressant effects and 20/23 studies identified potential anxiolytic effects. In clinical studies, 5/7 identified potential antidepressant effects in major depressive disorder, 1/2 identified potential anxiolytic effects in generalized anxiety disorder, and 3/3 identified potential antidepressant effects in bipolar disorders.
CONCLUSION
While there is some evidence that the 5-HT7 receptor system may be a potential target for treating mood and anxiety disorders, many agents included in the review also bind to other receptors. Further research is needed using drugs that bind specifically to 5-HT7 receptors to examine treatment proof of concept further.
Topics: Animals; Humans; Anti-Anxiety Agents; Antidepressive Agents; Anxiety Disorders; Depressive Disorder, Major
PubMed: 37994803
DOI: 10.1177/02698811231211228 -
Frontiers in Pharmacology 2023Ondansetron is a selective antagonist of the serotonin 5-HT3 receptor that is commonly used to treat morning sickness. It is estimated that 70%-80% of pregnant women...
Ondansetron is a selective antagonist of the serotonin 5-HT3 receptor that is commonly used to treat morning sickness. It is estimated that 70%-80% of pregnant women suffer from morning sickness, a condition characterized by nausea and vomiting. However, it is still controversial regarding its safety during pregnancy, and continued research will be necessary to fully understand the risks and benefits associated with its use. Therefore, we aimed to identify and provide details of the efficacy and safety of ondansetron in clinical trials. A search was conducted of the ClinicalTrials.gov database on 13 April 2023, using the search term "ondansetron and pregnancy." Inclusion and exclusion criteria were defined to identify relevant clinical trials. The inclusion criteria encompassed clinical trials related to pregnancy that utilized ondansetron as a treatment, while other clinical trials were excluded from consideration. All data extractions such as study title, study status, study type, intervention details, and outcome were collected. A total of 18 clinical trials were identified, of which only 6 focused on studying the effects of ondansetron. Their respective study titles, statuses, conditions, interventions, outcome measures, and enrollment sizes have been written in detail. The information collected from these trials will contribute to our understanding of the potential benefits and risks of ondansetron in the context of pregnancy and its complications. Ondansetron has been shown to be an effective treatment for nausea and vomiting, including pregnancy-related morning sickness. Further research is needed to better understand the potential risks and benefits associated with its use in pregnant women. ClinicalTrials.gov, identifier.
PubMed: 37936910
DOI: 10.3389/fphar.2023.1291235 -
Journal of Psychiatric Research Nov 2023The benefits of serotonin 3 receptor antagonists (5-HT3R-As) in obsessive-compulsive disorder (OCD) treatment remain unclear. Thus, this study aimed to perform a... (Meta-Analysis)
Meta-Analysis
The benefits of serotonin 3 receptor antagonists (5-HT3R-As) in obsessive-compulsive disorder (OCD) treatment remain unclear. Thus, this study aimed to perform a systematic review and a random-effects meta-analysis, including double-blind, randomized, placebo-controlled trials (DBRPCTs). The outcomes include the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) total score (primary), Y-BOCS obsession subscale score, Y-BOCS compulsive subscale score, treatment response, remission rate, all-cause discontinuation, and incidence of individual adverse events (nervousness/restlessness/anxiety, insomnia, headache, dizziness/lightheadedness, decreased appetite, constipation, nausea/vomiting, diarrhea, dry mouth, sweating/increased perspiration, itching/pruritus, tremor, and sexual dysfunction/decreased libido). The mean differences (MD) for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals (CIs) were calculated. Our study included 10 DBRPCTs (n = 628). Pooled 5-HT3R-As outperformed placebo regarding Y-BOCS total score (MD = -5.08, 95% CI = -7.04, -3.12, N = 9, n = 560), Y-BOCS obsession subscale score, Y-BOCS compulsive subscale score, treatment response, and remission rate. Individually, all 5-HT3R-As outperformed placebo regarding Y-BOCS total score (granisetron: MD = -5.59, 95% CI = -8.79, -2.39, N = 3, n = 178, ondansetron: MD = -5.72, 95% CI = -8.06, -3.37, N = 6, n = 331, tropisetron: MD = -2.87, 95% CI = -5.19, -0.550, N = 1, n = 96). However, all-cause discontinuation and incidence of individual adverse events between pooled 5-HT3R-As and placebo were not significantly different. In conclusion, our meta-analysis suggested 5-HT3R-As as efficacious for symptom improvement in individuals with OCD. However, the number of individuals included in each study was small; thus, a replication randomized trial of 5-HT3R-As should be conducted using a larger sample size.
Topics: Humans; Obsessive-Compulsive Disorder; Serotonin 5-HT3 Receptor Antagonists; Randomized Controlled Trials as Topic; Outcome Assessment, Health Care
PubMed: 37866327
DOI: 10.1016/j.jpsychires.2023.10.029 -
Journal of Psychopharmacology (Oxford,... Nov 2023Major depressive disorder (MDD) is a leading cause of global disability. Several lines of evidence implicate the dopamine system in its pathophysiology. However, the... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Major depressive disorder (MDD) is a leading cause of global disability. Several lines of evidence implicate the dopamine system in its pathophysiology. However, the magnitude and consistency of the findings are unknown. We address this by systematically reviewing in vivo imaging evidence for dopamine measures in MDD and meta-analysing these where there are sufficient studies.
METHODS
Studies investigating the dopaminergic system using positron emission tomography or single photon emission computed tomography in MDD and a control group were included. Demographic, clinical and imaging measures were extracted from each study, and meta-analyses and sensitivity analyses were conducted.
RESULTS
We identified 43 studies including 662 patients and 801 controls. Meta-analysis of 38 studies showed no difference in mean or mean variability of striatal D receptor availability ( = 0.06, = 0.620), or combined dopamine synthesis and release capacity ( = 0.19, = 0.309). Dopamine transporter (DAT) availability was lower in the MDD group in studies using DAT selective tracers ( = -0.56, = 0.006), but not when tracers with an affinity for serotonin transporters were included ( = -0.21, = 0.420). Subgroup analysis showed greater dopamine release ( = 0.49, = 0.030), but no difference in dopamine synthesis capacity ( = -0.21, = 0.434) in the MDD group. Striatal D receptor availability was lower in patients with MDD in two studies.
CONCLUSIONS
The meta-analysis indicates striatal DAT availability is lower, but D receptor availability is not altered in people with MDD compared to healthy controls. There may be greater dopamine release and lower striatal D receptors in MDD, although further studies are warranted. We discuss factors associated with these findings, discrepancies with preclinical literature and implications for future research.
Topics: Humans; Dopamine; Depressive Disorder, Major; Tomography, Emission-Computed, Single-Photon; Positron-Emission Tomography; Receptors, Dopamine D2; Dopamine Plasma Membrane Transport Proteins
PubMed: 37811803
DOI: 10.1177/02698811231200881 -
Schizophrenia Research. Cognition Dec 2023In a previous meta-analysis, the use of serotonin(5-HT) receptor partial agonists of the azapirone class as an add-on therapy was associated with beneficial effects on...
BACKGROUND
In a previous meta-analysis, the use of serotonin(5-HT) receptor partial agonists of the azapirone class as an add-on therapy was associated with beneficial effects on positive symptoms and attention/processing speed in schizophrenia patients. This meta-analysis builds on that study by examining the effects of adjunctive treatment with 5-HT partial agonists in improving other domains of neurocognitive function in schizophrenia patients.
METHODS
A literature search was performed from 1987 to May 2023 to identify randomized controlled trials. The standardized mean difference (SMD) with 95 % confidence intervals (CI) was calculated when there were two or more studies. Four studies, involving 313 patients, met the inclusion criteria and were used in the analysis.
RESULTS
5-HT partial agonists (buspirone or tandospirone) did not have a significant effect on verbal learning (SMD = 0.08, 95 % CI = -0.31 to 0.47) or working memory (SMD = 0.15, 95 % CI = -0.09 to 0.39). Regarding executive functions (Wisconsin Card Sorting Test), positive but non-significant results were seen with the category number (SMD = 0.26, 95 % CI = -0.81 to 1.32), while non-significant effects were noted for percent preservation errors (SMD = -0.10, 95 % CI = -0.53 to 0.33).
CONCLUSIONS
The absence of any significant benefits in the cognitive domains studied here may have been due to the variance in the concomitant medication (typical vs atypical antipsychotic drugs), the level of cognition at baseline, or other factors. Further studies with various types of 5-HT agonists are warranted to examine the potential cognitive efficacy of stimulating these receptors.
PubMed: 37732133
DOI: 10.1016/j.scog.2023.100290 -
Obesity Reviews : An Official Journal... Nov 2023This systematic review collates studies of dietary or bariatric surgery interventions for obesity using positron emission tomography and single-photon emission computed... (Review)
Review
Effects of bariatric surgery and dietary interventions for obesity on brain neurotransmitter systems and metabolism: A systematic review of positron emission tomography (PET) and single-photon emission computed tomography (SPECT) studies.
This systematic review collates studies of dietary or bariatric surgery interventions for obesity using positron emission tomography and single-photon emission computed tomography. Of 604 publications identified, 22 met inclusion criteria. Twelve studies assessed bariatric surgery (seven gastric bypass, five gastric bypass/sleeve gastrectomy), and ten dietary interventions (six low-calorie diet, three very low-calorie diet, one prolonged fasting). Thirteen studies examined neurotransmitter systems (six used tracers for dopamine DRD2/3 receptors: two each for C-raclopride, F-fallypride, I-IBZM; one for dopamine transporter, I-FP-CIT; one used tracer for serotonin 5-HT receptor, F-altanserin; two used tracers for serotonin transporter, C-DASB or I-FP-CIT; two used tracer for μ-opioid receptor, C-carfentanil; one used tracer for noradrenaline transporter, C-MRB); seven studies assessed glucose uptake using F-fluorodeoxyglucose; four studies assessed regional cerebral blood flow using O-H O (one study also used arterial spin labeling); and two studies measured fatty acid uptake using F-FTHA and one using C-palmitate. The review summarizes findings and correlations with clinical outcomes, eating behavior, and mechanistic mediators. The small number of studies using each tracer and intervention, lack of dietary intervention control groups in any surgical studies, heterogeneity in time since intervention and degree of weight loss, and small sample sizes hindered the drawing of robust conclusions across studies.
Topics: Humans; Positron-Emission Tomography; Tomography, Emission-Computed, Single-Photon; Bariatric Surgery; Brain; Obesity; Neurotransmitter Agents
PubMed: 37699864
DOI: 10.1111/obr.13620