Imaging synaptic density in depression

Planar cell polarity proteins mediate ketamine-induced restoration of glutamatergic synapses in prefrontal cortical neurons in a mouse model for chronic stress

Single administration of low-dose ketamine has both acute and sustained anti-depressant effects. Sustained effect is associated with restoration of glutamatergic synapses in medial prefrontal cortic (mFPC) neurons. Ketamine induced profound changes in a number of molecular pathways in a mouse model for chronic stress. Cell-cell communication analyses predicted that planar-cell-polarity (PCP) signaling was decreased after chronic administration of corticosterone but increased following ketamine administration in most of the excitatory neurons. Similar decrease of PCP signaling in excitatory neurons was predicted in dorsolateral prefrontal cortical (dl-PFC) neurons of patients with major depressive disorder (MDD). We showed that the basolateral amygdala (BLA)-projecting infralimbic prefrontal cortex (IL PFC) neurons regulate immobility time in the tail suspension test and food consumption. Conditionally knocking out Celsr2 and Celsr3 or Prickle2 in the BLA-projecting IL PFC neurons abolished ketamine-induced synapse restoration and behavioral remission. Therefore, PCP proteins in IL PFC-BLA neurons mediate synapse restoration induced by of low-dose ketamine.

Adjunctive cariprazine as a novel effective strategy for treating major depressive disorder: A systematic review and meta-analysis

BACKGROUND

Cariprazine has been approved by the Food and Drug Administration for treating bipolar depression and as an adjunctive treatment for Major Depressive Disorder (MDD). However, it remains unclear about its pharmacological efficacy in treating MDD. Therefore, a meta-analysis was conducted to investigate the adjunctive use of cariprazine in MDD.

METHODS

Electronic databases were searched for eligible studies evaluating the efficacy and safety of cariprazine in patients with MDD up to November 15, 2023. The changes in Montgomery-Asberg Depression Rating Scale (MADRS) score and incidence of adverse events (AEs), which represents of efficacy and tolerability, are considered as the main outcomes.

RESULTS

A total of 3066 patients with MDD included in all across 5 RCTs. With regard to MADRS score, cariprazine group showed better results than control group (SMD = -0.12, 95% CI -0.19 to -0.04, P = 0.002, 5 RCTs, n = 3066). Cariprazine, meanwhile, improved the MADRS response (RR = 1.19, 95% CI 1.08 to 1.31, P = 0.0004, 5 RCTs, n = 3066). For safety outcomes, statistical difference was observed in AEs (RR = 1.26, 95% CI 1.18 to 1.35, P < 0.00001, 5 RCTs, n = 3077). The suicide ideation and SAEs showed no statistical difference between two groups.

CONCLUSION

Cariprazine demonstrated antidepressant effect as an augmentation therapy in treating MDD. Meanwhile, the tolerability of it was acceptable as an adjunctive treatment. However, studies with larger sample sizes are still needed to explore the optimal dosage.

Efficacy and safety of zuranolone for the treatment of depression: A systematic review and meta-analysis

Major depressive disorder (MDD) and postpartum depression (PPD) are common and burdensome conditions. This study aims to evaluate the efficacy and safety of zuranolone, a neuroactive steroid γ-aminobutyric acid type A receptors-positive allosteric modulator, in treating MDD and PPD. A comprehensive literature search was conducted until September 2023, identifying seven randomized controlled trials (RCTs). The results demonstrated that zuranolone significantly decreased Hamilton Rating Scale for Depression (HAM-D) scores in patients with PPD or MDD at day 15 (concluding the 14-day course) and day 42-45 (4 weeks after treatment cessation) compared with the placebo, albeit exhibiting a diminishing trend. Moreover, a higher percentage of patients with PPD or MDD achieved HAM-D response and remission with zuranolone treatment compared with placebo at day 15. However, zuranolone did not significantly increase the proportion of MDD patients achieving HAM-D remission at 42/43 days. Adverse events (AEs) such as somnolence, dizziness, and sedation were linked to zuranolone, with a higher but not statistically significant rate of discontinuation due to AEs in the zuranolone group. Overall, our findings support the rapid antidepressant effects of zuranolone in MDD and PPD, along with a relatively favorable safety and tolerability. Large-scale longitudinal RCTs are needed to evaluate the long-term efficacy of zuranolone.

[Targeting NMDAR/AMPAR: a promising pharmacotherapeutic approach for depressive disorders]

Depression is a leading cause of disability and reduced work capacity worldwide. The monoamine theory of the pathogenesis of depression has remained dominant for many decades, however, drugs developed on its basis have limited efficacy. Exploring alternative mechanisms underlying this pathology could illuminate new avenues for pharmacological intervention. Targeting glutamatergic pathways in the CNS, particularly through modulation of NMDA and AMPA receptors, demonstrates promising results. This review presents some existing drugs with glutamatergic activity and novel developments based on it to enhance the efficacy of pharmacotherapy for depressive disorders.

The efficacy and safety of some new GABAkines for treatment of depression: A systematic review and meta-analysis from randomized controlled trials

Positive allosteric modulators of γ-aminobutyric acid-A (GABAA) receptors, or GABAkines, play important roles in the treatment of depression, epilepsy, insomnia, and other disorders. Recently, some new GABAkines (zuranolone and brexanolone) have been administrated to patients with major depressive disorder (MDD) or postpartum depression (PPD) in randomized controlled trials (RCTs). This study aims to systematically review and examine the efficacy and safety of zuranolone or brexanolone for treatment of depression. A systematic literature retrieval was conducted through August 20, 2023. RCTs evaluating the efficacy and safety of zuranolone or brexanolone for treatment of depression were included. Eight studies (nine reports) were identified in the study. The percentages of patients with PPD achieving Hamilton Depression Rating Scale (HAM-D) response and remission were significantly higher after brexanolone or zuranolone administration compared with placebo at different points. The percentages of patients with MDD achieving HAM-D response and remission were significantly increased during the zuranolone treatment period compared with placebo. In addition, zuranolone caused more adverse events in patients with MDD compared with placebo. Our findings support the effects of brexanolone on improving the core symptoms of depression in patients with PPD, and the potential of zuranolone in treating patients with MDD or PPD.

Candidate biomarkers in psychiatric disorders: state of the field

The field of psychiatry is hampered by a lack of robust, reliable and valid biomarkers that can aid in objectively diagnosing patients and providing individualized treatment recommendations. Here we review and critically evaluate the evidence for the most promising biomarkers in the psychiatric neuroscience literature for autism spectrum disorder, schizophrenia, anxiety disorders and post-traumatic stress disorder, major depression and bipolar disorder, and substance use disorders. Candidate biomarkers reviewed include various neuroimaging, genetic, molecular and peripheral assays, for the purposes of determining susceptibility or presence of illness, and predicting treatment response or safety. This review highlights a critical gap in the biomarker validation process. An enormous societal investment over the past 50 years has identified numerous candidate biomarkers. However, to date, the overwhelming majority of these measures have not been proven sufficiently reliable, valid and useful to be adopted clinically. It is time to consider whether strategic investments might break this impasse, focusing on a limited number of promising candidates to advance through a process of definitive testing for a specific indication. Some promising candidates for definitive testing include the N170 signal, an event-related brain potential measured using electroencephalography, for subgroup identification within autism spectrum disorder; striatal resting-state functional magnetic resonance imaging (fMRI) measures, such as the striatal connectivity index (SCI) and the functional striatal abnormalities (FSA) index, for prediction of treatment response in schizophrenia; error-related negativity (ERN), an electrophysiological index, for prediction of first onset of generalized anxiety disorder, and resting-state and structural brain connectomic measures for prediction of treatment response in social anxiety disorder. Alternate forms of classification may be useful for conceptualizing and testing potential biomarkers. Collaborative efforts allowing the inclusion of biosystems beyond genetics and neuroimaging are needed, and online remote acquisition of selected measures in a naturalistic setting using mobile health tools may significantly advance the field. Setting specific benchmarks for well-defined target application, along with development of appropriate funding and partnership mechanisms, would also be crucial. Finally, it should never be forgotten that, for a biomarker to be actionable, it will need to be clinically predictive at the individual level and viable in clinical settings.

Post-Traumatic Stress Disorder among Emergency Medical Technicians and its Relationship with Occupational Stress and Depression: Post-Corona Screening, Zanjan, 2022

Objective

Emergency medical technicians (EMTs) are at risk of developing post-traumatic stress disorder (PTSD) as a result of seeing painful events involving suspected COVID-19 patients and being concerned about potentially infecting themselves and their families. Therefore, screening for these disorders is essential in the post-Corona era. This study aimed to investigate the prevalence of PTSD among EMTs and its relationship with occupational stress and depression when dealing with patients with suspected COVID-19.

Methods

This cross-sectional study was conducted on EMTs at Zanjan University of Medical Sciences using a convenience sampling method. Data were collected using a demographic information questionnaire, PTSD checklist, occupational stress questionnaire, and the Goldberg depression scale. The data were analyzed using SPSS software. Statistical tests such as Pearson correlation and logistic regression analysis were used to evaluate the data.

Result

205 EMTs participated in this cross-sectional study. The mean and standard deviation of PTSD was 37.13±12.93 (17-85), and according to the cut-off (45), the prevalence of PTSD was 30.7%. There was a direct and significant association between the total PTSD and depression scores (r=0.435, p=0.001). Some occupational stress domains, such as demand (r=0.306, p=0.001), colleague support (r=0.149, p=0.033), and communication (r=0.293, p=0.001) had a significant association with PTSD. The domains of sadness in depression (OR=1.074, p=0.027) and demands in occupational stress (OR=1.872, p=0.029) were the most important predictors of PTSD. Among demographic variables, employment status was the most important protective factor for PTSD (OR=0.378, p=0.038).

Conclusion

PTSD affected one-third of EMTs, and it had a significant relationship with various dimensions of depression and occupational stress. Due to the chronic nature of these diseases, policymakers are advised to prioritize psychological screening of EMTs as part of the post-Corona policy.

Thomas F, Battaglia F. High-frequency rTMS modulates emotional behaviors and structural plasticity in layers II/III and V of the mPFC

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive neuromodulation technique, and it has been increasingly used as a nonpharmacological intervention for the treatment of various neurological and neuropsychiatric diseases, including depression. In humans, rTMS over the prefrontal cortex is used to induce modulation of the neural circuitry that regulates emotions, cognition, and depressive symptoms. However, the underlying mechanisms are still unknown. In this study, we investigated the effects of a short (5-day) treatment with high-frequency (HF) rTMS (15 Hz) on emotional behavior and prefrontal cortex morphological plasticity in mice. Mice that had undergone HF-rTMS showed an anti-depressant-like activity as evidenced by decreased immobility time in both the Tail Suspension Test and the Forced Swim Test along with increased spine density in both layer II/III and layer V apical and basal dendrites. Furthermore, dendritic complexity assessed by Sholl analysis revealed increased arborization in the apical portions of both layers, but no modifications in the basal dendrites branching. Overall, these results indicate that the antidepressant-like activity of HF-rTMS is paralleled by structural remodeling in the medial prefrontal cortex.