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Early life stress (ELS) is defined as a short or chronic period of trauma, environmental or social deprivation, which can affect different neurochemical and behavioral patterns during adulthood. Zebrafish (Danio rerio ) have been widely used as a model system to understand human neurodevelopmental disorders and display translationally relevant behavioral and stress‐regulating systems. In this study, we aimed to investigate the effects of moderate ELS by exposing young animals (6‐weeks postfertilization), for 3 consecutive days, to three stressors, and analyzing the impact of this on adult zebrafish behavior (16‐week postfertilization). The ELS impact in adults was assessed through analysis of performance on tests of unconditioned memory (free movement pattern Y‐maze test), exploratory and anxiety‐related task (novel tank diving test), and social cohesion (shoaling test). Here, we show for the first time that moderate ELS increases the number of alternations in turn‐direction compared to repetitions in the unconditioned Y‐maze task, suggesting increased working memory, but has no effect on shoal cohesion, locomotor profile, or anxiety‐like behavior. Overall, our data suggest that moderate ELS may be linked to adaptive flexibility which contributes to build “resilience” in adult zebrafish by improving working memory performance.

Additional file 6: Fig. S6. Deletion of microglial Bin1 does not impact cell morphology. (A) Following the deletion of Bin from microglia (Cx3cr1CreER-Bin1 cKO), no obvious change in microglial morphology was observed. There didn’t seem to be any effect on LPS administration. (B) Quantification of FracLac hull and circle morphometric analysis of microglia from LPS-injected mice. Microglia in the primary somatosensory cortex (SSp) of Cx3cr1CreER-Bin1 cKO mice had larger span ratios than Cx3cr1CreER control mice. *, p

Additional file 4: Fig. S4. Transcript cluster analysis of in vitro dataset demonstrates the extent of transcriptional dysregulation by Bin1 KD in primary cultured microglia. (A) Volcano plot of transcript expression following LPS exposure identifies several AD- and DAM-related genes affected by this endotoxin. The color scheme depicted is based on microglial gene co-expression module assignment, as described in Rangaraju et al. [21]. (B) Volcano plot illustrating genes regulated by BIN1 following LPS exposure highlights several inflammatory genes dysregulated by Bin1 siRNA. (C-F) Gene ontology expression analysis identified important cellular functions affected by misexpressed gene clusters.

Additional file 9: Fig. S9. Generation of BV2 KO microglia lacking BIN1 expression by CRISPR/Cas9 gene editing. (A) Lentiviral constructs expressing a sgRNA targeting a region within the Bin1 invariant exon 3 (KO) or a non-target sgRNA were used to generate stably transduced pools of BV2 KO and control (WT) cells. Two independent pools of WT and KO were further characterized. Sequencing (using a reverse primer) across the target sequence of the two KO pools as well as the sequences of individual cloned inserts from the PCR products are aligned to Bin1 exon 3 sequence. Numbering is based on the RefSeq NM_009668.2. (B) WT control and Bin1 KO pools retain similar morphology. (C) Immunoblot analysis demonstrates that stable Bin1 KO BV2 pools do not express BIN1 protein under basal conditions or following LPS stimulation.

Additional file 7: Fig. S7. Summary of in vivo transcriptional changes and cytokine production. (A-B) Genes which are positively (A) and negatively (B) regulated by BIN1 (i.e., decrease and increase respectively with Bin1 knockout) are summarised from the in vivo NanoString dataset by raw transcript counts (top panel) and normalized expression (relative to Bin1fl/fl as the WT equivalent; bottom panel). (C) Summary of cytokine expression in brain lysates (measured by Luminex). Data plotted as mean ± SEM.

Additional file 5: Fig. S5. Flow cytometry gating strategy for mouse brain-isolated microglia, weight, and temperature analysis during LPS injections. (A) Cells isolated from mouse brains were gated by scatter (single mononuclear cells) and fluorescence (CD11b+CD45int) to sort microglial populations. (B-C) LPS-injected mice lost significant weight during injections. Reduced Cx3cr1 expression (in Cx3cr1CreER) augmented the LPS-induced weight-loss recorded in control (Bin1fl/fl) animals, which was attenuated by the additional deletion of microglial Bin1 (Cx3cr1CreER-Bin1 cKO). (D-E) LPS had no effect on body temperature before or after injection. (F) Immunofluorescence staining of Bin1fl/fl mouse brains suggests that peripheral LPS injections did not affect the microglial expression or localization of BIN1. (G) NanoString analysis of mRNA transcripts found no change in Bin1 expression following LPS injections. (H) Relative levels of Bin1 iso10 mRNA transcripts quantified from FACS-isolated microglia, following saline or LPS injections.

Additional file 8: Fig. S8. Whole-brain qRT-PCR analysis of selected homeostatic- and DAM-related genes, and master myeloid-regulating transcription factor. Raw dataset for the analysis summarised in Fig. 8A. Transcript levels of genes encoding homeostatic proteins (P2ry12, Tmem119), DAM proteins (Itgax, Cst7, Cd68, Trem2, Spp1), and transcription factor (Sfpi1) were analysed by qRT-PCR. With the exception of the DAM-related gene Spp1, all were upregulated following LPS stimulation in a BIN1-dependent manner. *, p

Additional file 2: Fig. S2. Exon 11 splicing in microglia. (A) RT-PCR across exon 11 found no inclusion of exon 11 in FACS-isolated microglia from mouse brain, with no change in splicing following LPS injections (left). iMG cells differentiated from human iPSCs showed negligible inclusion of exon 11 (right). Some low-level inclusion of exon 11 is evident in the grey matter sample of human post-mortem brain tissue. (B) Schematic of BIN1 exons and primer locations for RT-PCR amplification across exon 7, exon 11, and the CLAP domain / exon 17. The strategy used to discern alternate splicing of exons 13-17 is indicated. The four mouse microglial Bin1 isoforms identified in this study are depicted at the bottom. BAR, the BIN-amphiphysin/Rvs domain; PI, the phosphoinositide binding motif (encoded by the muscle-specific exon 11), CLAP, the clathrin and AP2 binding domain, SH3, the Src homology 3 domain.

Additional file 3: Fig. S3. Bin1 siRNA treatment of primary microglia dysregulates DAM gene transcripts without affecting cell viability. CD11b + enriched primary mouse microglia (p0-3) were cultured for 48 h in the presence of either sham siRNA or Bin1 siRNA (equimolar concentrations). (A) Cell viability within the CD45+ microglia population was assessed by flow cytometry (Live/Dead Fixable Blue viability dye). N = 3 independent experiments were performed per condition. (B) Bin1 transcript levels (NanoString) increase following LPS stimulation of cultured microglia. (C) Volcano plot showing key genes differentially expressed following Bin1 KD. (D) Transcript expression of key AD-related microglial genes are dysregulated following the loss of Bin1 expression, an effect augmented by LPS-induced inflammatory signaling.

BIN1, a member of the BAR adaptor protein family, is a significant late-onset Alzheimer’s disease risk factor. Here, we investigated BIN1 function in the brain using conditional knockout (cKO) models. The loss of neuronal Bin1 expression resulted in select impairment of spatial learning and memory. Examination of hippocampal CA1 excitatory synapses revealed a deficit in presynaptic release probability and slower depletion of neurotransmitter during repetitive stimulation, suggesting altered vesicle dynamics in Bin1 cKO mice. Super-resolution and immunoelectron microscopy localized BIN1 to presynaptic sites in excitatory synapses. Bin1 cKO significantly reduced synapse density and altered presynaptic active zone protein cluster formation. Finally, 3D-electron microscopy reconstruction analysis uncovered a significant increase of docked and reserve pool of synaptic vesicles at hippocampal synapses in Bin1 cKO mice. Our results demonstrate a non-redundant role for BIN1 in presynaptic regulation, thus providing novel insights into BIN1's fundamental function in synaptic physiology relevant to Alzheimer’s disease.

Regulatory agencies recommend that centrally active drugs are tested for abuse potential before approval. Standard preclinical assessments are conducted in rats or non-human primates (NHPs). This study evaluated the ability of the zebrafish conditioned place preference (CPP) model to predict human abuse outcomes. Twenty-seven compounds from a variety of pharmacological classes were tested in zebrafish CPP, categorized as positive or negative, and analyzed using standard diagnostic tests of binary classification to determine the likelihood that zebrafish correctly predict robust positive signals in human subjective effects studies (+HSE) and/or Drug Enforcement Administration drug scheduling. Results were then compared with those generated for rat self-administration and CPP, as well as NHP self-administration, using this same set of compounds. The findings reveal that zebrafish concordance and sensitivity values were not significantly different from chance for both +HSE and scheduling. Although significant improvements in specificity and negative predictive values were observed for zebrafish relative to +HSE, specificity without sensitivity provides limited predictive value. Moreover, assessments in zebrafish provided no added value for predicting scheduling. By contrast, rat and NHP models generally possessed significantly improved concordance, sensitivity, and positive predictive values for both clinical measures. Although there may be predictive value with compounds from specific pharmacological classes (e.g., µ-opioid receptor agonists, psychostimulants) for zebrafish CPP, altogether these data highlight that using the current methodology, the zebrafish CPP model does not add value to the preclinical assessment of abuse potential.

Zebrafish are an important model species with unparalleled potential to advance understanding of the genetics and neurobiology of behaviour through genetic and pharmacological screening and mutant analysis. However, advances using this species have been limited by the lack of robust, standardised methodology and equipment suitable for assessing adult behaviour. Here we describe a simple, fully automated, computer based, operant system for measuring behaviour in juvenile and adult zebrafish and provide detailed protocols for appetitive and aversive assays to assess cognitive function in adult zebrafish. Applications include the study of cognition in zebrafish (and other similar sized fish species) and in zebrafish models of psychiatric and neurodegenerative diseases (e.g., Alzheimer’s disease, schizophrenia, Huntington’s disease, frontotemporal dementia), and characterisation of the role of select brain regions, neurotransmitter systems and genes in zebrafish. Further, the scalable nature of the system makes the protocols suitable for use in pharmacological and genetic screening programmes.

With lifespans rapidly increasing worldwide there has been a marked increase in age-related diseases—particularly those affecting cognition—that place a major socioeconomic burden on society. Despite this, much of what occurs during the aging process at a molecular level is poorly understood, facilitating the need for a greater understanding of the processes involved. In recent years, zebrafish have proved a useful model for the identification of genetic and cellular mechanisms affecting a variety of disease processes. Here we review the potential of zebrafish as a model for the study of cognitive ageing.

Deficits in impulse control are related to a number of psychiatric diagnoses, including attention deficit hyperactivity disorder, addiction, and pathological gambling. Despite increases in our knowledge about the underlying neurochemical and neuroanatomical correlates, understanding of the molecular and cellular mechanisms is less well established. Understanding these mechanisms is essential in order to move towards individualized treatment programs and increase efficacy of interventions. Zebrafish are a very useful vertebrate model for exploring molecular processes underlying disease owing to their small size and genetic tractability. Their utility in terms of behavioral neuroscience, however, hinges on the validation and publication of reliable assays with adequate translational relevance. Here, we report an initial pharmacological validation of a fully automated zebrafish version of the commonly used five-choice serial reaction time task using a variable interval pre-stimulus interval. We found that atomoxetine reduced anticipatory responses (0.6 mg/kg), whereas a high-dose (4 mg/kg) methylphenidate increased anticipatory responses and the number of trials completed in a session. On the basis of these results, we argue that similar neurochemical processes in fish as in mammals may control impulsivity, as operationally defined by anticipatory responses on a continuous performance task such as this, making zebrafish potentially a good model for exploring the molecular basis of impulse control disorders and for first-round drug screening.

Report by Gary Sudwarts, SHO Checked by David Foler, Senior Registrar in Accident and Emergency Great Ormand Street Hospital In [a patient with a pneumothorax] are [plain chest x rays] reliable [in predicting volume of air in the chest]? A 22-year-old male presents to you in Accident and Emergency complaining of sudden onset of shortness of breath and right sided pleuritic chest pain. He has clinical signs in …

Background: Uterine artery embolisation (UAE) for symptomatic fibroids has been shown to be an effective and beneficial procedure in our South African population, especially considering any cultural stigma related to hysterectomy. Post procedural pain following UAE can be very significant. Regular review of pain management protocols in our population is therefore warranted. In particular, the benefit of intra-arterial lignocaine as an adjunctive analgesic following UAE remains uncertain. Method: A single institution retrospective comparative study was undertaken through review of folders of patients who were treated for symptomatic uterine fibroids by UAE between July 2016 and November 2019. Two groups were compared – those who underwent UAE without the use of intraarterial lignocaine (Control group) and those who received intra-arterial lignocaine (Study group). Baseline characteristics and periprocedural outcomes were compared together with an 11-Point pain scale which was recorded during the post procedural rounds at the end of the day. Results: A total of 473 patients were included in the study, with 142 patients in the Control group and 331 patients in the study group. No significant differences were found in the 11-point pain scores between the two groups (p=0.34). However, additional medication usage was slightly higher in the Control group (p=0.05), together with longer hospital stay (p