Search

Background: Clozapine is associated with the risk of serious neutropenia. However, this risk might decrease over time, meaning that indefinite absolute neutrophil count (ANC) monitoring could be unnecessary. We aimed to determine the epidemiology and timing of clozapine-associated neutropenia outcomes, to investigate variables that might contribute to the odds of neutropenia, and to determine risk of competing neutropenic events during clozapine treatment., Methods: We performed a retrospective analysis of the Australian and New Zealand Viatris Pharmacovigilance system (one of two monitoring databases for these two countries) between June 6, 1990, and Oct 25, 2022. Patients were excluded from analysis if they commenced clozapine before 1990, did not have a haematology test within 2 weeks of commencement date, or had no follow-up. We measured minor neutropenia (ANC 1·0-1·5 × 10 9 per L) and serious neutropenia (ANC <1·0 × 10 9 per L) leading to cessation of clozapine within 6 weeks of the neutropenic event. We determined the rates of minor and serious neutropenia and calculated odds ratios (ORs) for the likelihood of neutropenia leading to cessation. For serious neutropenia leading to cessation, we used time-to-event to calculate rolling weekly averages and to perform competing risk analysis of outcomes using Cox proportional hazards models and a Fine-Gray subdistribution hazards regression model. For the subset of data where information on previous clozapine use was available, we did an analysis for participants who did and did not have previous clozapine exposure., Findings: We included 26 630 people, with 2·6 million ANC values. Within the total cohort, 17 585 people (66%) were male, 9025 (33·9%) female, and 20 (0·1%) other gender, and the mean age was 36·1 years (SD 13·7). We did not have data on race or ethnicity. Of the 26 630 people taking clozapine, 1146 (4·3%) had minor neutropenia, 313 (1·2%) had serious neutropenia leading to cessation, and 223 (0·8%) had serious neutropenia unrelated to clozapine without cessation. In people with no previous exposure to clozapine (n=15 973), the cumulative incidence of serious neutropenia leading to cessation was 0·9% at 18 weeks and 1·4% at 2 years; the weekly incidence rate for serious neutropenia leading to cessation peaked at 9 weeks (0·128%) and fell to a rolling average weekly incidence of 0·001% by 2 years. For minor neutropenia, the cumulative incidence was 1·7% at 18 weeks and 3·5% at 2 years; the weekly incidence rate peaked at 9 weeks (0·218%) and fell to a stable rolling average of 0·01%. The median time to a serious neutropenic event leading to cessation was 17 weeks (IQR 9·96-102). Previous clozapine exposure reduced the risk of serious neutropenia leading to cessation (OR 0·19, 95% CI 0·12-0·31; p <0·0001)., Interpretation: Most serious neutropenia leading to clozapine cessation occurs within 18 weeks of treatment and becomes negligible after 2 years. Weekly haematological monitoring after the first 18 weeks could be safely reduced to once every 4 weeks and ceased after 2 years unless clinically indicated. Clozapine retrial after interruption with 2 cumulative years of unremarkable testing might not require further haematological monitoring. A serious neutropenia ANC threshold of ≤1·0 × 10 9 per L could be used in more jurisdictions., Funding: None., Competing Interests: Declaration of interests NW has received speaker fees from Ostuka, Lundbeck, and Janssen. SRC has received grants and served as consultant, adviser, or Continuing Medical Education speaker for the following entities: Otsuka Australia, Lundbeck Australia, Janssen-Cilag Australia, and Servier Australia. SK reports receiving speaker fees from Lundbeck. KN, NM, SE-P, HM, and DS declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Given the role of low-grade inflammation in the pathophysiology of major depressive disorder (MDD), anti-inflammatory strategies may improve treatment outcomes in some patients. However, it is controversial whether they can be used as adjunctive treatments and whether pre-treatment levels of inflammation can predict treatment outcomes. This study was conducted to measure the efficacy of anti-inflammatory augmentation of antidepressant treatment in MDD patients; and to investigate whether treatment response was dependent on baseline inflammation levels. This parallel-group randomised, double-blind, placebo-controlled trial was conducted at the University of Adelaide (Australia). Participants with MDD were randomised to receive vortioxetine with celecoxib or vortioxetine with placebo for six weeks, and baseline blood high sensitivity C reactive protein levels were measured. Primary outcome was change in depressive symptoms (Montgomery-Åsberg Depression Rating Scale) and secondary outcomes included change in cognition (THINC-integrated tool - Codebreaker task) and functioning (Functioning Assessment Short Test) over 6 weeks. There was no evidence of superior efficacy of celecoxib augmentation over placebo on depressive symptom severity, response and remission rates, cognition and psychosocial functioning. There was also no evidence that pre-treatment inflammation levels modified the effect of celecoxib augmentation versus placebo. This observed lack of efficacy of celecoxib add-on does not support the use of celecoxib augmentation of antidepressants in the treatment of MDD in a cohort that mostly comprises treatment-resistant individuals. Additionally, C-reactive protein may not be suitable to predict treatment selection and response in MDD. The study was registered on the Australian New Zealand Clinical Trials Registry: ACTRN12617000527369 (www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12617000527369p)., Competing Interests: Declaration of Competing Interest Professor Bernhard T. Baune received speaker/consultation fees from: AstraZeneca, Lundbeck, Pfizer, Takeda, Servier, Bristol Myers Squibb, Otsuka, LivaNova and Janssen-Cilag. A/Professor Scott R. Clark received speaker/consultation fees from: Janssen-Cilag, Lundbeck, Otsuka and Servier and research funding from Janssen-Cilag, Lundbeck, Otsuka and Gilead. A/Professor K. Oliver Schubert received speaker/consultation fees from Janssen-Cilag, and received research funding from Lundbeck, Janssen-Cilag, and Gilead. Ms Emma Sampson, A/Professor Hikaru Hori, Dr Natalie Mills and Dr Célia Fourrier report no financial relationships with commercial interests. H. Lundbeck A/S provided the vortioxetine that was used in the study. H. Lundbeck A/S did not exert any influence on the study conception, study design, data collection, data analyses and manuscript preparation and publication., (Copyright © 2021 Elsevier B.V. and ECNP. All rights reserved.)

In order to accelerate the understanding of pathophysiological mechanisms and clinical biomarker discovery and in psychiatry, approaches that integrate multiple -omics platforms are needed. We introduce a workflow that investigates a narrowly defined psychiatric phenotype, makes use of the potent and cost-effective discovery technology of gene expression microarrays, applies Weighted Gene Co-Expression Network Analysis (WGCNA) to better capture complex and polygenic traits, and finally explores gene expression findings on the proteomic level using targeted mass-spectrometry (MS) technologies. To illustrate the effectiveness of the workflow, we present a proteomic analysis of peripheral blood plasma from patient's remitted major depressive disorder (MDD) who experience ongoing cognitive deficits. We show that co-expression patterns previous detected on the transcript level could be replicated for plasma proteins, as could the module eigengene correlation with cognitive performance. Further, we demonstrate that functional analysis of multi-omics data has the potential to point to cellular mechanisms and candidate biomarkers for cognitive dysfunction in MDD, implicating cell cycle regulation by cyclin D3 (CCND3), regulation of protein processing in the endoplasmatic reticulum by Thioredoxin domain-containing protein 5 (TXND5), and modulation of inflammatory cytokines by Tripartite Motif Containing 26 (TRI26)., Significance: This paper discusses how data from multiple -omics platforms can be integrated to accelerate biomarker discovery in psychiatry. Using the phenotype of cognitive impairment in remitted major depressive disorder (MDD) as an example, we show that the application of a systems biology approach - weighted gene co-expression network analysis (WGCNA) - in the discovery phase, and targeted proteomic follow-up of results, provides a structured avenue towards uncovering novel candidate markers and pathways for personalized clinical psychiatry., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Polycations are used for a number of biological applications, including antibiotics and gene therapy. One aspect of the use of polycation gene carriers such as polyethylenemine (PEI) in gene therapy that is not well understood is their ability to escape from the vesicles they are internalized in. Here, in an attempt to gain a better understanding of PEI interaction with endosomal lipids under osmotic stress, we performed investigations using monolayers and vesicles derived from a mixture of neutral and negative lipids (1,2-dipalmitoylphosphatidylcholine (DPPC) and bis(monoacylglycero)phosphate (BMP), respectively). X-ray reflectivity (XR) and Langmuir trough measurements confirmed PEI adsorption to the negatively charged membrane. Confocal microscopy imaging indicated that PEI adsorption actually increases the overall integrity of the DPPC/BMP vesicle against osmotic stresses while also causing overall deformation and permeabilization of the lipid membrane, thus leading to leakage of contents from the interior of the vesicle. These confocal microscopy observations were also supported by data gathered by dynamic light scattering (DLS)., Statement of Significance: In recent decades, researchers have investigated polyamine-based gene delivery systems as useful alternatives to viral gene carriers. One step that is crucial to the performance of polyamine gene carriers such as polyethylenemine (PEI) is escape from late endosomal vesicles during intracellular delivery. However, the ability of polyamine/DNA polyplexes to effectively escape from endosomes is a little-understood part of the gene therapy techniques that use these polyplexes. Here, we performed investigations using monolayers and vesicles derived from a mixture of neutral and negative lipids (1,2-dipalmitoylphosphatidylcholine (DPPC) and bis(monoacylglycero)phosphate (BMP), respectively) as model systems for late endosomes in order to examine the interactions of PEI with the DPPC/BMP membranes and study the subsequent effects on the stability and permeability of these membranes., (Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Background: Lithium is a first-line treatment in bipolar disorder, but individual response is variable. Previous studies have suggested that lithium response is a heritable trait. However, no genetic markers of treatment response have been reproducibly identified., Methods: Here, we report the results of a genome-wide association study of lithium response in 2563 patients collected by 22 participating sites from the International Consortium on Lithium Genetics (ConLiGen). Data from common single nucleotide polymorphisms (SNPs) were tested for association with categorical and continuous ratings of lithium response. Lithium response was measured using a well established scale (Alda scale). Genotyped SNPs were used to generate data at more than 6 million sites, using standard genomic imputation methods. Traits were regressed against genotype dosage. Results were combined across two batches by meta-analysis., Findings: A single locus of four linked SNPs on chromosome 21 met genome-wide significance criteria for association with lithium response (rs79663003, p=1·37 × 10(-8); rs78015114, p=1·31 × 10(-8); rs74795342, p=3·31 × 10(-9); and rs75222709, p=3·50 × 10(-9)). In an independent, prospective study of 73 patients treated with lithium monotherapy for a period of up to 2 years, carriers of the response-associated alleles had a significantly lower rate of relapse than carriers of the alternate alleles (p=0·03268, hazard ratio 3·8, 95% CI 1·1-13·0)., Interpretation: The response-associated region contains two genes for long, non-coding RNAs (lncRNAs), AL157359.3 and AL157359.4. LncRNAs are increasingly appreciated as important regulators of gene expression, particularly in the CNS. Confirmed biomarkers of lithium response would constitute an important step forward in the clinical management of bipolar disorder. Further studies are needed to establish the biological context and potential clinical utility of these findings., Funding: Deutsche Forschungsgemeinschaft, National Institute of Mental Health Intramural Research Program., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Clozapine is an atypical antipsychotic drug used in the treatment of schizophrenia, which has been shown to reverse behavioural and dendritic spine deficits in mice. It has recently been shown that deficiency of 14-3-3ζ has an association with schizophrenia, and that a mouse model lacking this protein displays several schizophrenia-like behavioural deficits. To test the effect of clozapine in this mouse model, 14-3-3ζ KO mice were administered clozapine (5mg/kg) for two weeks prior to being analysed in a test battery of cognition, anxiety, and despair (depression-like) behaviours. Following behavioural testing brain samples were collected for analysis of specific anatomical defects and dendritic spine formation. We found that clozapine reduced despair behaviour of 14-3-3ζ KO mice in the forced swim test (FST) and altered the behaviour of wild types and 14-3-3ζ KO mice in the Y-maze task. In contrast, clozapine had no effects on hippocampal laminar defects or decreased dendritic spine density observed in 14-3-3ζ KO mice. Our results suggest that clozapine may have beneficial effects on clinical behaviours associated with deficiencies in the 14-3-3ζ molecular pathway, despite having no effects on morphological defects. These findings may provide mechanistic insight to the action of this drug., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Oxidized phospholipids (oxPLs) generated nonenzymatically display pleiotropic biological actions in inflammation. Their generation by cellular cyclooxygenases (COXs) is currently unknown. To determine whether platelets generate prostaglandin (PG)-containing oxPLs, then characterize their structures and mechanisms of formation, we applied precursor scanning-tandem mass spectrometry to lipid extracts of agonist-activated human platelets. Thrombin, collagen, or ionophore activation stimulated generation of families of PGs comprising PGE₂ and D₂ attached to four phosphatidylethanolamine (PE) phospholipids (16:0p/, 18:1p/, 18:0p/, and 18:0a/). They formed within 2 to 5 min of activation in a calcium, phospholipase C, p38 MAP kinases, MEK1, cPLA₂, and src tyrosine kinase-dependent manner (28.1 ± 2.3 pg/2 × 10⁸ platelets). Unlike free PGs, they remained cell associated, suggesting an autocrine mode of action. Their generation was inhibited by in vivo aspirin supplementation (75 mg/day) or in vitro COX-1 blockade. Inhibitors of fatty acyl reesterification blocked generation significantly, while purified COX-1 was unable to directly oxidize PE in vitro. This indicates that they form in platelets via rapid esterification of COX-1 derived PGE₂/D₂ into PE. In summary, COX-1 in human platelets acutely mediates membrane phospholipid oxidation via formation of PG-esterified PLs in response to pathophysiological agonists.

Platelet activation represents a key event in normal hemostasis as well as during platelet plug formation related to thrombosis. Nitro-fatty acids are novel endogenously produced signaling mediators exerting pluripotent anti-inflammatory actions in cells and tissues. We have recently shown that nitroarachidonic acid inhibits thromboxane synthesis during platelet activation by affecting prostaglandin endoperoxide H synthase (PGHS). Herein, we investigated the regulation of human platelet activation by NO(2)AA and describe a novel mechanism involving protein kinase C (PKC) inhibition. NO(2)AA-mediated antiplatelet effects were characterized using mass spectrometry, confocal microscopy, flow cytometry, western blot and aggregometry. Incubation of NO(2)AA with human platelets caused a significant reduction in platelet sensitivity to thrombin, ADP, arachidonic acid (AA), and phorbol ester (PMA). These effects were cGMP-independent and did not involve Ca(2+) store-dependent mobilization. In contrast, signaling downstream of conventional PKC activation, such as α-granule secretion and extracellular signal regulated kinase 2 activation was strongly inhibited by NO(2)AA. Immunofluorescence confocal microscopy confirmed NO(2)AA-mediated inhibition of PKCα translocation to the membrane. In summary, we demonstrate that NO(2)AA inhibits platelet activation through modulation of PKCα activity as a potential novel mechanism for platelet regulation in vivo., (Copyright © 2013 Elsevier Inc. All rights reserved.)

5-Lipoxygenase (5-LOX) plays key roles in infection and allergic responses. Herein, four 5-LOX-derived lipids comprising 5-hydroxyeicosatetraenoic acid (HETE) attached to phospholipids (PLs), either phosphatidylethanolamine (PE) or phosphatidylcholine (18:0p/5-HETE-PE, 18:1p/5-HETE-PE, 16:0p/5-HETE-PE, and 16:0a/5-HETE-PC), were identified in primary human neutrophils. They formed within 2 minutes in response to serum-opsonized Staphylococcus epidermidis or f-methionine-leucine-phenylalanine, with priming by lipopolysaccharide, granulocyte macrophage colony-stimulating factor, or cytochalasin D. Levels generated were similar to free 5-HETE (0.37 ± 0.14 ng vs 0.55 ± 0.18 ng/10(6) cells, esterified vs free 5-HETE, respectively). They remained cell associated, localizing to nuclear and extranuclear membrane, and were formed by fast esterification of newly synthesized free 5-HETE. Generation also required Ca(2+), phospholipase C, cytosolic and secretory phospholipase A(2), 5-LOX activating protein, and mitogen-activated protein kinase/extracellular signal-regulated kinase kinase 1. 5-HETE-PLs were detected in murine S epidermidis peritonitis, paralleling neutrophil influx, and in effluent from Gram-positive human bacterial peritonitis. Formation of neutrophil extracellular traps was significantly enhanced by 5-LOX inhibition but attenuated by HETE-PE, whereas 5-HETE-PE enhanced superoxide and interleukin-8 generation. Thus, new molecular species of oxidized PL formed by human neutrophils during bacterial infection are identified and characterized.

Localization of circulating lymphocytes to a site of inflammation is paramount for the development and maintenance of an immune response. In vitro studies using cell lines have previously demonstrated that rolling and adhesion of lymphocytes on endothelium requires CD44 interactions with hyaluronan (HA). To date, whether CD44 has a role in mediating CD4(+)-polarized T-helper 1 (Th1) and Th2 lymphocyte interactions with the endothelium in vivo is yet to be determined. In this study we used intravital microscopy to demonstrate that both Th1 and Th2 lymphocytes use CD44 to roll and adhere to tumor necrosis factor-alpha (TNFalpha)-activated microvasculature. Furthermore, chimeric studies imply that CD44 expression by both the endothelium and lymphocytes is essential for these interactions to occur. HA was also necessary for T cell-endothelial cell interactions in vivo and Th1 and Th2 cells rolled on immobilized HA in vitro via CD44. In vitro, both Th1 and Th2 lymphocytes have increased expression of CD44 and greater binding of fluorescent HA than naive cells. The interactions of Th1 and Th2 cells were entirely dependent upon both P-selectin and CD44 in vivo, but did not appear to be counter ligands in vitro. Taken together, these results suggest that CD44 and HA are key to both Th1 and Th2 lymphocyte interactions with the TNFalpha-activated endothelium and raises the possibility of cooperativity between the P-selectin/PSGL-1 and HA/CD44 pathways for Th1 and Th2 rolling in vivo.

"Exercise is good for you; you must exercise, and just do it" are common admonitions to fibromyalgia (FM) patients by health professionals. "I can't exercise; I hurt too much to exercise; and, I don't have enough energy to exercise" are equally common responses from patients with FM. Such exchanges can lead to frustration for both patient and provider. The factor that neither participant in the dialogue is addressing is that exercise carries both risks and benefits for persons with FM. Although for decades exercise has been acknowledged to be a key component of the treatment of FM, the majority of FM patients remain aerobically unfit, with poor muscle strength and limited flexibility. Unfit muscle is theoretically more prone to muscle microtrauma, which causes localized pain and may trigger widespread pain through disordered central processing. The purpose of this article is to provide practicing health care providers with guidelines for prescribing exercise to FM patients that take into account the risk/benefit ratio. A sample exercise prescription is included.