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Introduction: Adolescent idiopathic scoliosis (AIS) and schizophrenia (SCZ) are two distinct conditions with poorly understood aetiologies that both emerge in otherwise healthy young adolescents. One rare genetic condition associated with both phenotypic outcomes is the 22q11.2 deletion (22q11DS). This microdeletion, encompassing 47 genes, occurs in approximately 1 in 2,148 live births and confers a 20-fold higher risk for both AIS and schizophrenia compared to the general population. In the general population (non-22q11DS carriers), AIS and SCZ have also been reported to be related and genetic studies suggest the involvement of genetic variants implicated in the central nervous functioning. In this study, our objective was to further investigate genetic overlaps between these conditions in the general population. Specifically, we aimed to explore the role of genes within the 22q11.2 region, not only in terms of common variants but also their potential impact on gene networks and biopathways., Methods: We used summary statistics from three genome-wide association studies (GWAS): two focused on AIS (n = 11,210), and one on schizophrenia (n = 36,989). To explore potential overlaps between the two conditions, we conducted a comparative analysis on the significance-based ranked single nucleotide polymorphisms (SNPs) that are associated with both AIS and SCZ. Next, we employed in silico analyses to assess gene-networks enrichment for the most significant SNPs and investigate the contribution of genes within the 22q11.2 region. Post-hoc analysis was conducted to explore the biological pathways correlated with SNPs significantly associated with both AIS and SCZ., Results: The in silico analyses revealed a significant (adjusted-p < 0.05) genetic overlap between SCZ and both AIS cohorts. The top 3% of the most significant SNPs associated with both conditions exhibited a distinct enrichment cluster which is unlikely to be a result of chance (p < 3e-04). The gene-networks analyses showed a significant overlap of 26-41% with the ones involving genes in the 22q11DS region. However, there was no overlap between SNPs in this region and the most significant SNPs identified in the GWAS., Conclusion: This study revealed compelling evidence that beyond the shared association with 22q11DS as a rare genetic variant, AIS and SCZ exhibit common genetic risk variants and an overlap of important genes. The gene networks enriched by the most significant SNPs for both conditions also intersect with the ones involving genes in the 22q11DS region. However, SNPs within this region were not overrepresented among the most significant SNPs from GWAS for both conditions. Notably, gene networks linked to the risk for both conditions suggest an involvement of biopathways related to cellular signaling and neuronal development., (© 2024. The Author(s).)

Astrocytes, a type of glial cell in the central nervous system (CNS), adopt diverse states in response to injury that are influenced by their location relative to the insult. Here, we describe a platform for spatially resolved, single-cell transcriptomics and proteomics, called tDISCO (tissue-digital microfluidic isolation of single cells for -Omics). We use tDISCO alongside two high-throughput platforms for spatial (Visium) and single-cell transcriptomics (10X Chromium) to examine the heterogeneity of the astrocyte response to a cortical ischemic stroke in male mice. We show that integration of Visium and 10X Chromium datasets infers two astrocyte populations, proximal or distal to the injury site, while tDISCO determines the spatial boundaries and molecular profiles that define these populations. We find that proximal astrocytes show differences in lipid shuttling, with enriched expression of Apoe and Fabp5. Our datasets provide a resource for understanding the roles of astrocytes in stroke and showcase the utility of tDISCO for hypothesis-driven, spatially resolved single-cell experiments., (© 2024. The Author(s).)

Pannexin 1 (Panx1) forms ATP-permeable membrane channels that play roles in purinergic signaling in the nervous system. A link between Panx1 activity and neurodegenerative disorders including Parkinson's disease (PD) has been suggested, but experimental evidence is limited. Here, a zebrafish model of PD was produced by exposing panx1a +/+ and panx1a -/- zebrafish larvae to 6-hydroxydopamine (6-OHDA). Electrical stimulation in a microfluidic chip and quantitative real-time-qPCR of zebrafish larvae tested the role of Panx1 in both pathological and normal conditions. After 72-h treatment with 6-OHDA, the electric-induced locomotor activity of 5 days post fertilization (5dpf) panx1a +/+ larvae were reduced, while the stimulus did not affect locomotor activity of age-matched panx1a -/- larvae. A RT-qPCR analysis showed an increase in the expression of genes that are functionally related to dopaminergic signaling, like the tyrosine hydroxylase (th2) and the leucine-rich repeat kinase 2 (lrrk2). Extending the 6-OHDA treatment duration to 120 h caused a significant reduction in the locomotor response of 7dpf panx1a -/- larvae compared to the untreated panx1a -/- group. The RT-qPCR data showed a reduced expression of dopaminergic signaling genes in both genotypes. It was concluded that the absence of Panx1a channels compromised dopaminergic signaling in 6-OHDA-treated zebrafish larvae and that the increase in the expression of dopaminergic genes was transient, most likely due to a compensatory upregulation. We propose that zebrafish Panx1a models offer opportunities to shed light on PD's physiological and molecular basis. Panx1a might play a role on the progression of PD, and therefore deserves further investigation., (© 2023 The Authors. Journal of Neuroscience Research published by Wiley Periodicals LLC.)

The molecular mechanisms of excitation/inhibition imbalances promoting seizure generation in epilepsy patients are not fully understood. Evidence suggests that Pannexin1 (Panx1), an ATP release channel, modulates the excitability of the brain. In this report, we performed electrophysiological, behavioral, and molecular phenotyping experiments on zebrafish larvae bearing genetic or pharmacological knockouts of Panx1a and Panx1b channels, each homologous to human PANX1. When Panx1a function is lost, or both channels are under pharmacological blockade, seizures with ictal-like events and seizure-like locomotion are reduced in the presence of pentylenetetrazol. Transcriptome profiling by RNA-seq demonstrates a spectrum of distinct metabolic and cell signaling states which correlate with the loss of Panx1a. Furthermore, the pro- and anticonvulsant activities of both Panx1 channels affect ATP release and involve the purinergic receptor P2rx7. Our findings suggest a subfunctionalization of Panx1 enabling dual roles in seizures, providing a unique and comprehensive perspective to understanding seizure mechanisms in the context of this channel., (© 2022. The Author(s).)

Pannexin1 (Panx1) can form ATP-permeable channels that play roles in the physiology of the visual system. In the zebrafish two ohnologs of Panx1, Panx1a and Panx1b, have unique and shared channel properties and tissue expression patterns. Panx1a channels are located in horizontal cells of the outer retina and modulate light decrement detection through an ATP/pH-dependent mechanisms and adenosine/dopamine signaling. Here, we decipher how the strategic localization of Panx1b channels in the inner retina and ganglion cell layer modulates visually evoked motor behavior. We describe a panx1b knockout model generated by TALEN technology. The RNA-seq analysis of 6 days post-fertilization larvae is confirmed by real-time PCR and paired with testing of locomotion behaviors by visual motor and optomotor response tests. We show that the loss of Panx1b channels disrupts the retinal response to an abrupt loss of illumination and it decreases the larval ability to follow leftward direction of locomotion in low light conditions. We concluded that the loss of Panx1b channels compromises the final output of luminance as well as motion detection. The Panx1b protein also emerges as a modulator of the circadian clock system. The disruption of the circadian clock system in mutants suggests that Panx1b could participate in non-image forming processes in the inner retina.

Pannexin 1 (Panx1) forms ATP-permeable membrane channels that play roles in the nervous system. The analysis of roles in both standard and pathological conditions benefits from a model organism with rapid development and early onset of behaviors. Such a model was developed by ablating the zebrafish panx1a gene using TALEN technology. Here, RNA-seq analysis of 6 days post fertilization larvae were confirmed by Real-Time PCR and paired with testing visual-motor behavior and in vivo electrophysiology. Results demonstrated that loss of panx1a specifically affected the expression of gene classes representing the development of the visual system and visual processing. Abnormal swimming behavior in the dark and the expression regulation of pre-and postsynaptic biomarkers suggested changes in dopaminergic signaling. Indeed, altered visuomotor behavior in the absence of functional Panx1a was evoked through D1/D2-like receptor agonist treatment and rescued with the D2-like receptor antagonist Haloperidol. Local field potentials recorded from superficial areas of the optic tectum receiving input from the retina confirmed abnormal responses to visual stimuli, which resembled treatments with a dopamine receptor agonist or pharmacological blocking of Panx1a. We conclude that Panx1a functions are relevant at a time point when neuronal networks supporting visual-motor functions undergo modifications preparing for complex behaviors of freely swimming fish.

Behavioral responses of zebrafish larvae to environmental cues are important functional readouts that should be evoked on-demand and studied phenotypically in behavioral, genetical and developmental investigations. Very recently, it was shown that zebrafish larvae execute a voluntary and oriented movement toward the positive electrode of an electric field along a microchannel. Phenotypic characterization of this response was not feasible due to larva's rapid movement along the channel. To overcome this challenge, a microfluidic device was introduced to partially immobilize the larva's head while leaving its mid-body and tail unrestrained in a chamber to image motor behaviors in response to electric stimulation, hence achieving quantitative phenotyping of the electrically evoked movement in zebrafish larvae. The effect of electric current on the tail-beat frequency and response duration of 5-7 days postfertilization zebrafish larvae was studied. Investigations were also performed on zebrafish exposed to neurotoxin 6-hydroxydopamine and larvae carrying a pannexin1a (panx1a) gene knockout, as a proof of principle applications to demonstrate on-demand movement behavior screening in chemical and mutant assays. We demonstrated for the first time that 6-hydroxydopamine leads to electric response impairment, levodopa treatment rescues the response and panx1a is involved in the electrically evoked movement of zebrafish larvae. We envision that our technique is broadly applicable as a screening tool to quantitatively examine zebrafish larvae's movements in response to physical and chemical stimulations in investigations of Parkinson's and other neurodegenerative diseases, and as a tool to combine recent advances in genome engineering of model organisms to uncover the biology of electric response., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.)

: Congenital factor VII (FVII) deficiency is a rare bleeding disorder with an estimated prevalence of 1 per 500 000 in the general population. On-demand replacement therapy is the main therapeutic choice in patients with congenital FVII deficiency. Inhibitor formation against exogenous FVII is very rare and can cause challenges in the management of the disorder. The present study was conducted to assess the prevalence of FVII inhibitor in 50 patients with congenital FVII deficiency under on-demand or prophylaxis treatment by recombinant activated FVII. All patients with confirmed congenital FVII deficiency were assessed for inhibitor development in regular intervals. Inhibitor titer was determined by a modified Nijmegen-Bethesda assay. The study results were analyzed by SPSS software. Among all cases, two patients (4%) developed an FVII inhibitor. Case 1 was a 14-year-old boy with severe FVII deficiency (FVII activity <1%) with regular prophylaxis. The patient was a high-responder with high-titer FVII inhibitor (170 Bethesda Unit). This patient, who had a history of intracranial hemorrhage, had undergone brain surgery three times. The second patient was a 70-years old man with on-demand therapy that also developed a high-titer inhibitor (10 Bethesda Unit). This patient had experienced easy bruising and endured a few surgeries for his brain tumor and, finally, succumbed to the disease. Although the inhibitor formation is a rare phenomenon, it may result in a significant challenge to manage the affected patients.