A pilot study of the role of the BDNF Val66Met polymorphism in response to exercise-augmented exposure therapy for posttraumatic stress disorder.

Brain-Derived Neurotrophic Factor (BDNF) is implicated in extinction learning, which is a primary mechanism of exposure therapy for posttraumatic stress disorder (PTSD). Brief aerobic exercise has been shown to promote BDNF release and augment extinction learning. On the premise that the Val allele of the BDNF Val66Met polymorphism facilitates greater release of BDNF, this study examined the extent to which the Val allele of the BDNF polymorphism predicted treatment response in PTSD patients who underwent exposure therapy combined with aerobic exercise or passive stretching. PTSD patients (N = 85) provided saliva samples in order to extract genomic DNA to identify Val/Val and Met carriers of the BDNF Val66Met genotype, and were assessed for PTSD severity prior to and following a 9-week course of exposure therapy combined with aerobic exercise or stretching. The sample comprised 52 Val/Val carriers and 33 Met carriers. Patients with the BDNF high-expression Val allele display greater reduction of PTSD symptoms at posttreatment than Met carriers. Hierarchical regression analysis indicated that greater PTSD reduction was specifically observed in Val/Val carriers who received exposure therapy in combination with the aerobic exercise. This finding accords with animal and human evidence that the BDNF Val allele promotes greater extinction learning, and that these individuals may benefit more from exercise-augmented extinction. Although preliminary, this result represents a possible avenue for augmented exposure therapy in patients with the BDNF Val allele.

A systematic review and meta-analysis of predictors of response to trauma-focused psychotherapy for posttraumatic stress disorder.

Although trauma-focused psychotherapy (T-F psychotherapy) is the treatment of choice for posttraumatic stress disorder (PTSD), up to one half of patients do not respond to this treatment. Attempts to improve response to T-F psychotherapy have focused on augmenting fear extinction-based factors. Here, a systematic and meta-analytic review of predictors of T-F psychotherapy outcome was conducted with the goal of using an aggregate data-driven approach to elucidate baseline factors associated with treatment outcome. There were 114 studies that met inclusion criteria (N = 61, 970; Mage = 40.1 years; 40.1% female). There were 237 effect sizes across 24 meta-analytic categories. Poorer treatment response is associated with lower pretreatment levels of activation of fear-related brain regions, psychophysiological reactivity to fear provocation, trauma-related cognitions, anger, depression, high-risk alleles of genes linked to fear, lower levels of executive control, and social support. A range of other factors also predicted poorer responses including being male, non-Caucasian, older in age, early trauma occurrence, more trauma experience, history of combat trauma, as well as comorbid sleep, pain, poor quality life, and alcohol abuse difficulties. This review provides one potential explanation for the limited success of T-F psychotherapy augmentation strategies that have focused only on fear circuity mechanisms at the exclusion of other factors. Here, poor response relating to predictors of early trauma onset and comorbidity are consistent with clinical presentations of complex PTSD, which may suggest T-F psychotherapy is less effective for this condition. This collective evidence suggests that clinicians should consider a tailored approach that targets potential barriers to successful treatment response. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Combined effect of CYP2C19 and CYP2D6 genotypes on escitalopram serum concentration and its metabolic ratio in a European patient population.

AIMS: The aim of the present study was to investigate the impact of CYP2D6 genotype on exposure and metabolism of escitalopram in patients stratified by CYP2C19 genotype in a large real-world population. METHODS: Patients were included from a therapeutic drug monitoring service if they had measured serum concentration of escitalopram and the metabolite, N-desmethyl escitalopram, and performed CYP2C19 and CYP2D6 genotyping. Patients were divided into 16 combined genotype-predicted phenotype subgroups (poor [PM], intermediate [IM], normal [NM] and ultrarapid metabolizers [UM]) of CYP2C19/CYP2D6. The concentration-to-dose (CD) ratio and metabolite-to-parent ratio (metabolic ratio) of escitalopram were compared across subgroups using the Kruskal-Wallis test followed by Dunn's test with CYP2D6 NMs as the reference group. RESULTS: A total of 5067 patients were included in the study. A stepwise increase in escitalopram CD ratio by decreasing CYP2D6 activity was observed in all CYP2C19 subgroups, except for in CYP2C19 UMs. The percentage differences in escitalopram CD ratio between CYP2D6 PMs and NMs were 24% in CYP2C19 NMs (P < .001), 28% in CYP2C19 IMs (P < .001) and 31% in CYP2C19 PMs (P = .04). As for the CD ratio, CYP2D6 genotype effect on metabolic ratio increased stepwise by decreasing CYP2C19 metabolism. CONCLUSIONS: CYP2D6 genotype is of significant importance for the individual variation in escitalopram pharmacokinetics. The most relevant increase in escitalopram concentration is seen in individuals with decreased and/or absent CYP2C19 activity. By combining CYP2C19 and CYP2D6 genotypes, the optimal dose for patients may be predicted with greater precision than for CYP2C19 genotype alone.

Cognitive Behavior Therapy vs Mindfulness in Treatment of Prolonged Grief Disorder: A Randomized Clinical Trial.

Importance: Although grief-focused cognitive behavior therapies are the most empirically supported treatment for prolonged grief disorder, many people find this treatment difficult. A viable alternative for treatment is mindfulness-based cognitive therapy. Objective: To examine the relative efficacies of grief-focused cognitive behavior therapy and mindfulness-based cognitive therapy to reduce prolonged grief disorder severity. Design, Setting, and Participants: A single-blind, parallel, randomized clinical trial was conducted among adults aged 18 to 70 years with prolonged grief disorder, as defined in the International Classification of Diseases, 11th Revision, and assessed by clinical interview based on the Prolonged Grief-13 (PG-13) scale. Those with severe suicidal risk, presence of psychosis, or substance dependence were excluded. Between November 2012 and November 2022, eligible participants were randomized 1:1 to eleven 90-minute sessions of grief-focused cognitive behavior therapy or mindfulness-based cognitive therapy at a traumatic stress clinic in Sydney, Australia, with follow-up through 6 months. Interventions: Both groups received once-weekly 90-minute individual sessions for 11 weeks. Grief-focused cognitive behavior therapy comprised 5 sessions of recalling memories of the deceased, plus cognitive restructuring and planning future social and positive activities. Mindfulness-based cognitive therapy comprised mindfulness exercises adapted to tolerate grief-related distress. Main Outcomes and Measures: The primary outcome was change in prolonged grief disorder severity measured by the PG-13 scale assessed at baseline, 1 week posttreatment, and 6 months after treatment (primary outcome time point), as well as secondary outcome measures of depression, anxiety, grief-related cognition, and quality of life. Results: The trial included 100 participants (mean [SD] age, 47.3 [13.4] years; 87 [87.0%] female), 50 in the grief-focused cognitive behavior therapy condition and 50 in the mindfulness-based cognitive therapy condition. Linear mixed models indicated that at the 6-month assessment, participants in the grief-focused cognitive behavior therapy group showed greater reduction in PG-13 scale score relative to those in the mindfulness-based cognitive therapy group (mean difference, 7.1; 95% CI, 1.6-12.5; P = .01), with a large between-group effect size (0.8; 95% CI, 0.2-1.3). Participants in the grief-focused cognitive behavior therapy group also demonstrated greater reductions in depression as measured on the Beck Depression Inventory than those in the mindfulness-based cognitive therapy group (mean difference, 6.6; 95% CI, 0.5-12.9; P = .04) and grief-related cognition (mean difference, 14.4; 95% CI, 2.8-25.9; P = .02). There were no other significant differences between treatment groups and no reported adverse events. Conclusions and Relevance: In this study, grief-focused cognitive behavior therapy conferred more benefit for core prolonged grief disorder symptoms and associated problems 6 months after treatment than mindfulness-based cognitive therapy. Although both treatments may be considered for prolonged grief disorder, grief-focused cognitive behavior therapy might be the more effective choice, taking all factors into consideration. Trial Registration: anzctr.org.au Identifier: ACTRN12612000307808.

Clinical relevance of HLA-DQ eplet mismatch and maintenance immunosuppression with risk of allosensitization after kidney transplant failure.

The optimal immunosuppression management in patients with a failed kidney transplant remains uncertain. This study analyzed the association of class II HLA eplet mismatches and maintenance immunosuppression with allosensitization after graft failure in a well characterized cohort of 21 patients who failed a first kidney transplant. A clinically meaningful increase in cPRA in this study was defined as the cPRA that resulted in 50% reduction in the compatible donor pool measured from the time of transplant failure until the time of repeat transplantation, death, or end of study. The median cPRA at the time of failure was 12.13% (interquartile ranges = 0.00%, 83.72%) which increased to 62.76% (IQR = 4.34%, 99.18%) during the median follow-up of 27 (IQR = 18, 39) months. High HLA-DQ eplet mismatches were significantly associated with an increased risk of developing a clinically meaningful increase in cPRA (p = 0.02) and de novo DQ donor-specific antibody against the failed allograft (p = 0.02). We did not observe these associations in patients with high HLA-DR eplet mismatches. Most of the patients (88%) with a clinically meaningful increase in cPRA had both a high DQ eplet mismatch and a reduction in their immunosuppression, suggesting the association is modified by immunosuppression. The findings suggest HLA-DQ eplet mismatch analysis may serve as a useful tool to guide future clinical studies and trials which assess the management of immunosuppression in transplant failure patients who are repeat transplant candidates.

Structural and mechanistic insights into disease-associated endolysosomal exonucleases PLD3 and PLD4.

Endolysosomal exonucleases PLD3 and PLD4 (phospholipases D3 and D4) are associated with autoinflammatory and autoimmune diseases. We report structures of these enzymes, and the molecular basis of their catalysis. The structures reveal an intra-chain dimer topology forming a basic active site at the interface. Like other PLD superfamily members, PLD3 and PLD4 carry HxKxxxxD/E motifs and participate in phosphodiester-bond cleavage. The enzymes digest ssDNA and ssRNA in a 5'-to-3' manner and are blocked by 5'-phosphorylation. We captured structures in apo, intermediate, and product states and revealed a "link-and-release" two-step catalysis. We also unexpectedly demonstrated phosphatase activity via a covalent 3-phosphohistidine intermediate. PLD4 contains an extra hydrophobic clamp that stabilizes substrate and could affect oligonucleotide substrate preference and product release. Biochemical and structural analysis of disease-associated mutants of PLD3/4 demonstrated reduced enzyme activity or thermostability and the possible basis for disease association. Furthermore, these findings provide insight into therapeutic design.

Structural and mechanistic insights into disease-associated endolysosomal exonucleases PLD3 and PLD4.

Endolysosomal exonucleases PLD3 and PLD4 (phospholipases D3 and D4) are associated with autoinflammatory and autoimmune diseases. We report structures of these enzymes, and the molecular basis of their catalysis. The structures reveal an intra-chain dimer topology forming a basic active site at the interface. Like other PLD superfamily members, PLD3 and PLD4 carry HxKxxxxD/E motifs and participate in phosphodiester-bond cleavage. The enzymes digest ssDNA and ssRNA in a 5'-to-3' manner and are blocked by 5'-phosphorylation. We captured structures in apo, intermediate, and product states and revealed a 'link-and-release' two-step catalysis. We also unexpectedly demonstrated phosphatase activity via a covalent 3' phosphistidine intermediate. PLD4 contains an extra hydrophobic clamp that stabilizes substrate and could affect oligonucleotide substrate preference and product release. Biochemical and structural analysis of disease-associated mutants of PLD3/4 demonstrated reduced enzyme activity or thermostability and the possible basis for disease association. Furthermore, these findings provide insight into therapeutic design.

Synthesis and Preclinical Evaluation of 22-[18F]Fluorodocosahexaenoic Acid as a Positron Emission Tomography Probe for Monitoring Brain Docosahexaenoic Acid Uptake Kinetics.

Docosahexaenoic acid [22:6(n-3), DHA], a polyunsaturated fatty acid, has an important role in regulating neuronal functions and in normal brain development. Dysregulated brain DHA uptake and metabolism are found in individuals carrying the APOE4 allele, which increases the genetic risk for Alzheimer's disease (AD), and are implicated in the progression of several neurodegenerative disorders. However, there are limited tools to assess brain DHA kinetics in vivo that can be translated to humans. Here, we report the synthesis of an ω-radiofluorinated PET probe of DHA, 22-[18F]fluorodocosahexaenoic acid (22-[18F]FDHA), for imaging the uptake of DHA into the brain. Using the nonradiolabeled 22-FDHA, we confirmed that fluorination of DHA at the ω-position does not significantly alter the anti-inflammatory effect of DHA in microglial cells. Through dynamic PET-MR studies using mice, we observed the accumulation of 22-[18F]FDHA in the brain over time and estimated DHA's incorporation coefficient (K*) using an image-derived input function. Finally, DHA brain K* was validated using intravenous administration of 15 mg/kg arecoline, a natural product known to increase the DHA K* in rodents. 22-[18F]FDHA is a promising PET probe that can reveal altered lipid metabolism in APOE4 carriers, AD, and other neurologic disorders. This new probe, once translated into humans, would enable noninvasive and longitudinal studies of brain DHA dynamics by guiding both pharmacological and nonpharmacological interventions for neurodegenerative diseases.

Validation of next-generation sequencing-based chimerism testing for accurate detection and monitoring of engraftment in hematopoietic stem cell transplantation.

Allogenic hematopoietic stem cell transplantation (allo-HSCT) is a life-saving treatment for various hematological disorders. The success of allo-HSCT depends on the engraftment of donor cells and the elimination of recipient cells monitored through chimerism testing. We aimed to validate a next-generation sequencing (NGS)-based chimerism assay for engraftment monitoring and to emphasize the importance of including the most prevalent cell subsets in proficiency testing (PT) programs. We evaluated the analytical performance of NGS-based chimerism testing (AlloSeq-HCT and CareDx) with a panel of targeted 202 informative single-nucleotide polymorphisms (SNPs) (i.e., linearity and precision, analytical sensitivity and specificity, system accuracy, and reproducibility). We further compared the performance of our NGS panel with conventional short tandem repeat (STR) analysis in unfractionated whole blood and cell-subset-enriched CD3 and CD66. Our NGS-based chimerism monitoring assay has an impressive detection limit (0.3% host DNA) for minor alleles and analytical specificity (99.9%). Pearson's correlation between NGS- and STR-based chimerism monitoring showed a linear relationship with a slope of 0.8 and r = 0.973. The concordance of allo-HSCT patients using unfractionated whole blood, CD3, and CD66 was 0.95, 0.96, and 0.54, respectively. Utilization of CD3+ cell subsets for mixed chimerism detection yielded an average of 7.3 ± 7-fold higher donor percentage detection compared to their corresponding unfractionated whole blood samples. The accuracy of the NGS assay achieved a concordance of 98.6% on blinded external quality control STR samples. The reproducibility series showed near 100% concordance with respect to inter-assay, inter-tech, inter-instrument, cell flow kits, and AlloSeq-HCT software versions. Our study provided robust validation of NGS-based chimerism testing for accurate detection and monitoring of engraftment in allo-HSCT patients. By incorporating the cell subsets (CD3 and CD66), the sensitivity and accuracy of engraftment monitoring are significantly improved, making them an essential component of any PT program. Furthermore, the implementation of NGS-based chimerism testing shows potential to streamline high-volume transplant services and improve clinical outcomes by enabling early relapse detection and guiding timely interventions.

Novel alleles in the era of next-generation sequencing-based HLA typing calls for standardization and policy.

Next-Generation Sequencing (NGS) has transformed clinical histocompatibility laboratories through its capacity to provide accurate, high-throughput, high-resolution typing of Human Leukocyte Antigen (HLA) genes, which is critical for transplant safety and success. As this technology becomes widely used for clinical genotyping, histocompatibility laboratories now have an increased capability to identify novel HLA alleles that previously would not be detected using traditional genotyping methods. Standard guidelines for the clinical verification and reporting of novelties in the era of NGS are greatly needed. Here, we describe the experience of a clinical histocompatibility laboratory's use of NGS for HLA genotyping and its management of novel alleles detected in an ethnically-diverse population of British Columbia, Canada. Over a period of 18 months, 3,450 clinical samples collected for the purpose of solid organ or hematopoietic stem cell transplantation were sequenced using NGS. Overall, 29 unique novel alleles were identified at a rate of ∼1.6 per month. The majority of novelties (52%) were detected in the alpha chains of class II (HLA-DQA1 and -DPA1). Novelties were found in all 11 HLA classical genes except for HLA-DRB3, -DRB4, and -DQB1. All novelties were single nucleotide polymorphisms, where more than half led to an amino acid change, and one resulted in a premature stop codon. Missense mutations were evaluated for changes in their amino acid properties to assess the potential effect on the novel HLA protein. All novelties identified were confirmed independently at another accredited HLA laboratory using a different NGS assay and platform to ensure validity in the reporting of novelties. The novel alleles were submitted to the Immuno Polymorphism Database-Immunogenetics/HLA (IPD-IMGT/HLA) for official allele name designation and inclusion in future database releases. A nationwide survey involving all Canadian HLA laboratories confirmed the common occurrence of novel allele detection but identified a wide variability in the assessment and reporting of novelties. In summary, a considerable proportion of novel alleles were identified in routine clinical testing. We propose a framework for the standardization of policies on the clinical management of novel alleles and inclusion in proficiency testing programs in the era of NGS-based HLA genotyping.

Positive affect training to reduce mental health problems during the COVID-19 pandemic: a proof-of-concept randomised clinical trial.

BACKGROUND: The social restrictions occurring during the pandemic contributed to loss of many sources of reward, which contributes to poor mental health. OBJECTIVE: This trial evaluated a brief positive affect training programme to reduce anxiety, depression and suicidality during the pandemic. METHODS: In this single-blind, parallel, randomised controlled trial, adults who screened positive for COVID-19-related psychological distress across Australia were randomly allocated to either a 6-session group-based programme based on positive affect training (n=87) or enhanced usual care (EUC, n=87). Primary outcome was total score on the Hospital Anxiety and Depression Scale-anxiety and depression subscales assessed at baseline, 1-week post-treatment, 3 months (primary outcome time point) as well as secondary outcome measures of suicidality, generalised anxiety disorder, sleep impairment, positive and negative mood and COVID-19-related stress. FINDINGS: Between 20 September 2020 and 16 September 2021, 174 participants were enrolled into the trial. Relative to EUC, at 3-month follow-up the intervention led to greater reduction on depression (mean difference 1.2 (95% CI 0.4 to 1.9)), p=0.003), with a moderate effect size (0.5 (95% CI 0.2 to 0.9)). There were also greater reduction of suicidality and improvement in quality of life. There were no differences in anxiety, generalised anxiety, anhedonia, sleep impairment, positive or negative mood or COVID-19 concerns. CONCLUSIONS: This intervention was able to reduce depression and suicidality during adverse experiences when rewarding events were diminished, such as pandemics. CLINICAL IMPLICATIONS: Strategies to improve positive affect may be useful to reduce mental health issues. TRIAL REGISTRATION NUMBER: ACTRN12620000811909.

The yeast ALA synthase C-terminus positively controls enzyme structure and function.

5-Aminolevulinic acid synthase (ALAS) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme that catalyzes the first and rate-limiting step of heme biosynthesis in α-proteobacteria and several non-plant eukaryotes. All ALAS homologs contain a highly conserved catalytic core, but eukaryotes also have a unique C-terminal extension that plays a role in enzyme regulation. Several mutations in this region are implicated in multiple blood disorders in humans. In Saccharomyces cerevisiae ALAS (Hem1), the C-terminal extension wraps around the homodimer core to contact conserved ALAS motifs proximal to the opposite active site. To determine the importance of these Hem1 C-terminal interactions, we determined the crystal structure of S. cerevisiae Hem1 lacking the terminal 14 amino acids (Hem1 ΔCT). With truncation of the C-terminal extension, we show structurally and biochemically that multiple catalytic motifs become flexible, including an antiparallel ß-sheet important to Fold-Type I PLP-dependent enzymes. The changes in protein conformation result in an altered cofactor microenvironment, decreased enzyme activity and catalytic efficiency, and ablation of subunit cooperativity. These findings suggest that the eukaryotic ALAS C-terminus has a homolog-specific role in mediating heme biosynthesis, indicating a mechanism for autoregulation that can be exploited to allosterically modulate heme biosynthesis in different organisms.

Augmenting trauma-focused psychotherapy for post-traumatic stress disorder with brief aerobic exercise in Australia: a randomised clinical trial.

BACKGROUND: Although exposure therapy is central in most front-line psychotherapies of post-traumatic stress disorder (PTSD), many patients do not respond to this treatment. We aimed to investigate the effects of brief aerobic exercise on the efficacy of exposure therapy in reducing the severity of PTSD. METHODS: We did a single-blind, parallel, randomised controlled trial in Sydney, NSW, Australia. We included adults (aged ≥18 years) with clinician-diagnosed PTSD. We excluded participants aged 70 years or older, with imminent suicidal risk (reporting suicidal plan), presence of psychosis or substance dependence, history of moderate-to-severe traumatic brain injury, or presence of a physical disorder or impairment that might be exacerbated by aerobic exercise (eg, back pain). We randomly assigned participants (1:1) to nine 90-min weekly sessions of exposure therapy for PTSD with 10 min aerobic exercise or to the control group of exposure therapy with 10 min passive stretching. The primary outcome was PTSD severity measured by the clinician-administered PTSD scale 2 (CAPS-2), independently assessed at baseline, 1 week after treatment, and 6 months after treatment (primary outcome timepoint). FINDINGS: Between Dec 12, 2012, and July 25, 2018, we enrolled 130 participants with PTSD, with 65 (50%) participants randomly assigned to exposure therapy with exercise and 65 (50%) to exposure therapy with passive stretching, including 79 (61%) women and 51 (39%) men, with a mean age of 39·1 years (SD 14·4; range 18-69). 99 (76%) participants were White, 14 (11%) were Asian, and 17 (13%) were listed as other. At the 6-month follow-up assessment, participants in the exposure therapy with exercise group showed greater reductions in CAPS-2 scores relative to those in the exposure therapy with stretching group (mean difference 12·1 [95% CI 2·4-21·8]; p=0·023), which resulted in a moderate effect size of 0·6 (0·1-1·1). No adverse events associated with the intervention were reported. The trial was prospectively registered on the Australian and New Zealand Clinical Trials Registry, ACTRN12612000185864. INTERPRETATION: Brief aerobic exercise has the potential to augment long-term gains of exposure therapy for PTSD, which accords with evidence from studies in animals and humans on the role of exercise in modulating the extinction learning processes. This strategy might offer a simple and affordable means to augment treatment gains for exposure therapy in people with PTSD. FUNDING: Australian National Health and Medical Research Council.

Radiosynthesis of 20-[18F]fluoroarachidonic acid for PET-MR imaging: Biological evaluation in ApoE4-TR mice.

Dysreglulated brain arachidonic acid (AA) metabolism is involved in chronic inflammation and is influenced by apolipoprotein E4 (APOE4) genotype, the strongest genetic risk factor of late-onset Alzheimer's disease (AD). Visualization of AA uptake and distribution in the brain can offer insight into neuroinflammation and AD pathogenesis. Here we present a novel synthesis and radiosynthesis of 20-[18F]fluoroarachidonic acid ([18F]-FAA) for PET imaging using a convergent route and a one-pot, single-purification radiolabeling procedure, and demonstrate its brain uptake in human ApoE4 targeted replacement (ApoE4-TR) mice. By examining p38 phosphorylation in astrocytes, we found that fluorination of AA at the ω-position did not significantly alter its biochemical role in cells. The brain incorporation coefficient (K*) of [18F]-FAA was estimated via multiple methods by using an image-derived input function from the right ventricle of the heart as a proxy of the arterial input function and brain tracer concentrations assessed by dynamic PET-MR imaging. This new synthetic approach should facilitate the practical [18F]-FAA production and allow its translation into clinical use, making investigations of dysregulation of lipid metabolism more feasible in the study of neurodegenerative diseases.

Structural Basis for Allostery in PLP-dependent Enzymes.

Pyridoxal 5'-phosphate (PLP)-dependent enzymes are found ubiquitously in nature and are involved in a variety of biological pathways, from natural product synthesis to amino acid and glucose metabolism. The first structure of a PLP-dependent enzyme was reported over 40 years ago, and since that time, there is a steady wealth of structural and functional information revealed for a wide array of these enzymes. A functional mechanism that is gaining more appreciation due to its relevance in drug design is that of protein allostery, where binding of a protein or ligand at a distal site influences the structure, organization, and function at the active site. Here, we present a review of current structure-based mechanisms of allostery for select members of each PLP-dependent enzyme family. Knowledge of these mechanisms may have a larger potential for identifying key similarities and differences among enzyme families that can eventually be exploited for therapeutic development.

Instrumental aversion coding in the basolateral amygdala and its reversion by a benzodiazepine.

Punishment involves learning the relationship between actions and their adverse consequences. Both the acquisition and expression of punishment learning depend on the basolateral amygdala (BLA), but how BLA supports punishment remains poorly understood. To address this, we measured calcium (Ca2+) transients in BLA principal neurons during punishment. Male rats were trained to press two individually presented levers for food; when one of these levers also yielded aversive footshock, responding on this punished lever decreased relative to the other, unpunished lever. In rats with the Ca2+ indicator GCaMP6f targeted to BLA principal neurons, we observed excitatory activity transients to the footshock punisher and inhibitory transients to lever-presses earning a reward. Critically, as rats learned punishment, activity around the punished response transformed from inhibitory to excitatory and similarity analyses showed that these punished lever-press transients resembled BLA transients to the punisher itself. Systemically administered benzodiazepine (midazolam) selectively alleviated punishment. Moreover, the degree to which midazolam alleviated punishment was associated with how much punished response-related BLA transients reverted to their pre-punishment state. Together, these findings show that punishment learning is supported by aversion-coding of instrumental responses in the BLA and that the anti-punishment effects of benzodiazepines are associated with a reversion of this aversion coding.

Effectiveness of a Videoconferencing-Delivered Psychological Intervention for Mental Health Problems during COVID-19: A Proof-of-Concept Randomized Clinical Trial.

INTRODUCTION: Anxiety and depression have increased markedly during the COVID-19 pandemic. There is a lack of evidence-based strategies to address these mental health needs during the pandemic. OBJECTIVE: We aim to conduct a proof-of-concept trial of the efficacy of a brief group-based psychological intervention delivered via videoconferencing for adults in Australia distressed by the pandemic. METHODS: In this single-blind, parallel, randomised controlled trial, adults who screened positive for COVID-related psychological distress across Australia were randomly allocated to either a 6-session group-based program based on behavioural principles (n = 120) or enhanced usual care (EUC, n = 120). Primary outcome was total score on the Hospital Anxiety and Depression (HADS) anxiety and depression subscales assessed at baseline, 1 week posttreatment, 2 months (primary outcome time point), and 6 months after treatment, as well as secondary outcome measures of worry, sleep impairment, anhedonia, mood, and COVID-19-related stress. RESULTS: Between May 20, 2020, and October 20, 2020, 240 patients were enrolled into the trial. Relative to EUC, at 2 months participants receiving intervention showed greater reduction on anxiety (mean difference, 1.4 [95% CI, 0.3 to 2.6], p = 0.01; effect size, 0.4 [95% CI, 0.1 to 0.7]) and depression (mean difference, 1.6 [95% CI, 0.4 to 2.8], p = 0.009; effect size, 0.4 [95% CI, 0.2 to 0.7]) scales. These effects were maintained at 6 months. There were also greater reductions of worry, anhedonia, COVID-19-related fears, and contamination fears. CONCLUSIONS: This trial provides initial evidence that brief group-based behavioural intervention delivered via videoconferencing results in moderate reductions in common psychological problems arising during the COVID-19 pandemic. This program may offer a viable and scalable means to mitigate the rising mental health problems during the pandemic.

Neural processes during response inhibition in complex posttraumatic stress disorder.

BACKGROUND: A common feature of complex posttraumatic stress disorder (CPTSD) is impulsivity. Despite the importance of this characteristic in functional difficulties in CPTSD, little is known about its mechanisms. The aim of this study was to identify the distinctive neural profile of CPTSD during attempted inhibition. METHODS: The present study examined functional alterations in neural networks involved in inhibitory control across functional magnetic resonance imaging (fMRI) and electroencephalogram (EEG) paradigms in CPTSD (n = 30), PTSD (n = 40), and healthy control (n = 40) participants who completed a Go/NoGo response inhibition task during separate fMRI and EEG sessions. Brain activations were calculated during the NoGo trials relative to the baseline to evaluate response inhibition functioning. RESULTS: There was reduced bilateral thalamic activation in participants with CPTSD relative to PTSD and controls during inhibition trials, but no activation differences between PTSD and controls for this brain region. There were no differences in functional connectivity between the thalamus and other regions involved in cognitive control between groups. No differences were observed between groups on EEG responses. CONCLUSIONS: These findings provide initial evidence of aberrant functioning in the neurocircuitry of inhibitory control, involving the thalamus, in CPTSD. This evidence suggests that CPTSD is distinguished from PTSD by impaired neural processes implicated in response inhibition.

Neural correlates of emotional processing in panic disorder.

BACKGROUND: Deficits in emotional processing are conceptualized in prevailing models of anxiety to underpin key symptoms of panic disorder (PD). Neuroimaging studies show evidence of aberrant neural functioning in PD patients during emotional processing, however little is understood about how non-conscious emotional processing impacts neural processes. METHOD: We examined activation and functional connectivity differences in brain regions involved in emotional processing between PD and healthy controls (HC) during subliminal and supraliminal presentations of facial emotions. Twenty-two PD and 33 HC participants were shown happy, sad, neutral, fear, anger and disgust facial expressions during functional magnetic resonance imaging using a 3T MRI scanner. We performed voxelwise ROI analyses at FWE-corrected p < 0.05 for main effects of group and group*emotion interactions. RESULTS: There was less pregenual anterior cingulate cortex (pgACC) activation to subliminal presentations of happy and sad faces in PD compared to HC participants (group*emotion). In addition, PD patients had less pgACC - right amygdala connectivity than HC participants during sad and fear subliminal processing (group*emotion). PD patients also exhibited lower right cerebellum activity across all supraliminal presentations of facial expressions compared to HC. CONCLUSION: These findings suggest that there is aberrant neural processing in PD patients during both conscious and preconscious processing of both positive and negative stimuli, suggesting impaired recruitment of implicit regulatory networks during affective processing. It appears that PD patients may experience deficits in key regulatory connections between inhibitory and emotional neural networks at very early stages of processing of negative affective states.

Association between cardiometabolic disease multimorbidity and all-cause mortality in 2 million women and men registered in UK general practices.

BACKGROUND: Myocardial infarction (MI), stroke and diabetes share underlying risk factors and commonalities in clinical management. We examined if their combined impact on mortality is proportional, amplified or less than the expected risk separately of each disease and whether the excess risk is explained by their associated comorbidities. METHODS: Using large-scale electronic health records, we identified 2,007,731 eligible patients (51% women) and registered with general practices in the UK and extracted clinical information including diagnosis of myocardial infarction (MI), stroke, diabetes and 53 other long-term conditions before 2005 (study baseline). We used Cox regression to determine the risk of all-cause mortality with age as the underlying time variable and tested for excess risk due to interaction between cardiometabolic conditions. RESULTS: At baseline, the mean age was 51 years, and 7% (N = 145,910) have had a cardiometabolic condition. After a 7-year mean follow-up, 146,994 died. The sex-adjusted hazard ratios (HR) (95% confidence interval [CI]) of all-cause mortality by baseline disease status, compared to those without cardiometabolic disease, were MI = 1.51 (1.49-1.52), diabetes = 1.52 (1.51-1.53), stroke = 1.84 (1.82-1.86), MI and diabetes = 2.14 (2.11-2.17), MI and stroke = 2.35 (2.30-2.39), diabetes and stroke = 2.53 (2.50-2.57) and all three = 3.22 (3.15-3.30). Adjusting for other concurrent comorbidities attenuated these estimates, including the risk associated with having all three conditions (HR = 1.81 [95% CI 1.74-1.89]). Excess risks due to interaction between cardiometabolic conditions, particularly when all three conditions were present, were not significantly greater than expected from the individual disease effects. CONCLUSION: Myocardial infarction, stroke and diabetes were associated with excess mortality, without evidence of any amplification of risk in people with all three diseases. The presence of other comorbidities substantially contributed to the excess mortality risks associated with cardiometabolic disease multimorbidity.