Brain microvasculature defects and Glut1 deficiency syndrome averted by early repletion of the glucose transporter-1 protein

Haploinsufficiency of the SLC2A1 gene and paucity of its translated product, the glucose transporter-1 (Glut1) protein, disrupt brain function and cause the neurodevelopmental disorder, Glut1 deficiency syndrome (Glut1 DS). There is little to suggest how reduced Glut1 causes cognitive dysfunction and no optimal treatment for Glut1 DS. We used model mice to demonstrate that low Glut1 protein arrests cerebral angiogenesis, resulting in a profound diminution of the brain microvasculature without compromising the blood–brain barrier. Studies to define the temporal requirements for Glut1 reveal that pre-symptomatic, AAV9-mediated repletion of the protein averts brain microvasculature defects and prevents disease, whereas augmenting the protein late, during adulthood, is devoid of benefit. Still, treatment following symptom onset can be effective; Glut1 repletion in early-symptomatic mutants that have experienced sustained periods of low brain glucose nevertheless restores the cerebral microvasculature and ameliorates disease. Timely Glut1 repletion may thus constitute an effective treatment for Glut1 DS

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

Three mutations that cause fifferent [i.e. different] forms of canine neuronal ceroid lipofuscinosis

Title from title screen of research.pdf file (viewed on December 22, 2006).The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file."May 2006"Includes bibliographical references.Thesis (M.S.) University of Missouri-Columbia 2006.Dissertations, Academic -- University of Missouri--Columbia -- Veterinary biomedical sciences.Neuronal ceroid-lipofuscinosis (NCL), also known as Battens disease, is really a group of inherited neurodegenerative diseases. A common feature of the ceroid lipofuscinoses is the deposition of autofluorescent cytoplasmic storage material in cells in the brain, retina, and many other tissues. The major symptoms are mental retardation, visual failure, lose of motor skills, seizures, and eventually premature death. In the European countries and the USA, the disease affects one in 12,500 to 100,000 people. Usually children appear to be healthy at birth and develop normally until the onset of the disease. Canine NCLs have been reported in a variety of breeds where they are important as veterinary diseases and as potential models for human NCLs. We have discovered that a missense mutation in the CLN8 gene causes NCL in English Setters, a missense mutation in the CTSD gene causes American Bulldog NCL, and frame shift mutation in the CLN2 gene causes Dachshund NCL

Limited Phenotypic Effects of Selectively Augmenting the SMN Protein in the Neurons of a Mouse Model of Severe Spinal Muscular Atrophy

<div><p>The selective vulnerability of motor neurons to paucity of Survival Motor Neuron (SMN) protein is a defining feature of human spinal muscular atrophy (SMA) and indicative of a unique requirement for adequate levels of the protein in these cells. However, the relative contribution of SMN-depleted motor neurons to the disease process is uncertain and it is possible that their characteristic loss and the overall SMA phenotype is a consequence of low protein in multiple cell types including neighboring spinal neurons and non-neuronal tissue. To explore the tissue-specific requirements for SMN and, especially, the salutary effects of restoring normal levels of the protein to neuronal tissue of affected individuals, we have selectively expressed the protein in neurons of mice that model severe SMA. Expressing SMN pan-neuronally in mutant mice mitigated specific aspects of the disease phenotype. Motor performance of the mice improved and the loss of spinal motor neurons that characterizes the disease was arrested. Proprioceptive synapses on the motor neurons were restored and defects of the neuromuscular junctions mitigated. The improvements at the cellular level were reflected in a four-fold increase in survival. Nevertheless, mutants expressing neuronal SMN did not live beyond three weeks of birth, a relatively poor outcome compared to the effects of ubiquitously restoring SMN. This suggests that although neurons and, in particular, spinal motor neurons constitute critical cellular sites of action of the SMN protein, a truly effective treatment of severe SMA will require restoring the protein to multiple cell types including non-neuronal tissue.</p> </div

A partial phenotypic rescue of SMA mice augmented with the SMN protein in neuronal tissue.

<p>(<b>A</b>) Gross phenotypes of PND4 control (1) and SMA mice with (2) or without (3) the Nes-Cre transgene depicting a readily apparent size difference between the mutants and their normal littermate. (<b>B</b>) Weight curves of the three groups of mice highlighting the development at PND5 of a significant, albeit temporary difference between the mutants with and without an increase in the expression of SMN within the neurons. *, <i>p</i><0.05 and **, <i>p</i><0.01, <i>t</i> test, n>15 mice. (<b>C</b>) Expressing SMN within the neurons of SMA mice restored their ability to perform as well as controls at PND1. Additionally, motor skills were better than in littermates expressing ubiquitously low SMN at PND1, PND6 and PND9. *, <i>p</i><0.05; **, <i>p</i><0.01, one-way ANOVA, n≥7 mice of each genotype at all ages examined. (<b>D</b>) A comparison of lifespans, as assessed by Kaplan-Meier survival analysis, of SMA mice with or without enhanced levels of SMN protein within their neurons. Restoring SMN to the neurons of SMA mice boosted survival four-fold relative to that in littermates in which the rescue allele was not activated. <i>p</i><0.0001, log-rank test, n≥34 mice.</p

Targeted expression of SMN in neuronal tissue protects against spinal motor neuron loss in SMA mice.

<p>(<b>A</b>) Western blot analysis of tissue from PND10–12 controls (1) and SMA mice with (2) or without (3) the Nes-Cre transgene. An increase in SMN protein is observed specifically in the brains and spinal cords of SMA mice harboring the Nes-Cre transgene (lanes 2 in figure). (<b>B</b>) Immunohistochemical analysis of lumbar motor neurons of PND7 controls and SMA mice with or without the Nes-Cre transgene. Loss of motor neurons observed in the <i>SMN2;Smn^Res/Res</i> mice is arrested in mutants expressing SMN in their neurons. (<b>C</b>) Quantification of lumbar motor neuron numbers in the above mice. *, <i>p</i><0.05, one-way ANOVA; n≥3 mice. (<b>D</b>) Immuno-histochemical analysis of motor neurons depicting the restoration of gems (arrows) in SMA mice expressing neuronal SMN. (<b>E</b>) Quantification of gems within motor neurons of controls and mutants with or without the Nes-Cre transgene. ***, <i>p</i><0.001, one-way ANOVA; n≥50 motor neurons. Note: Scale bars in panel (B) – 100 µm, panel (D) – 10 µm.</p

Selective activation of the <i>Smn</i> rescue allele in nervous tissue of transgenic mice.

<p>(<b>A</b>) RT-PCR analysis of tissue from an adult (PND32) double transgenic <i>(Nes-Cre;Smn^Res/+)</i> mouse. The presence of the FL-SMN transcript specifically in brain and spinal cord is evidence of selective activation of the inducible <i>Smn</i> allele in nervous tissue. The persistence of the SMNΔ7 transcript is expected in these two tissues if even a low proportion of cells retain the un-recombined <i>Smn</i> allele. (<b>B</b>) Lumbar spinal cord sections from ROSA-YFP reporter mice with or without the Nes-Cre transgene, dually labeled with antibodies against the GFP and ChAT proteins. Widespread YFP expression including within ChAT positive motor neurons (inset) of only the double transgenic mice is consistent with pan-neuronal Cre expression from the Nes-Cre transgene. (<b>C</b>) Quantification of ChAT positive spinal motor neurons and parvalbumin (Pv) positive DRG proprioceptive sensory neurons co-expressing the YFP protein as a measure of the efficiency of Nes-Cre-driven recombination of floxed alleles. (<b>D</b>) DRGs from the lumbar spinal cord of ROSA-YFP reporter mice with or without the Nes-Cre transgene dual labeled with antibodies against Pv and GFP. YFP expression in the DRGs of only the double transgenic mice is evidence of the activation of floxed alleles within DRG proprioceptive sensory neurons. Note: Scale bars in panel (B) – 100 µm, panel (D) – 100 µm.</p