Project description:Many of the genes disrupted in autism are identified as histone-modifying enzymes and chromatin remodelers, most prominently those that mediate histone methylation/demethylation. However, the role of histone methylation enzymes in the pathophysiology and treatment of autism remains unknown. To address this, we used mouse models of haploinsufficiency of the Shank3 gene (a highly penetrant monogenic autism risk factor), which exhibits prominent autism-like social deficits. We found that histone methyltransferases EHMT1 and EHMT2, as well as histone lysine 9 dimethylation (specifically catalyzed by EHMT1/2), were selectively increased in the prefrontal cortex (PFC) of Shank3-deficient mice and autistic human postmortem brains. Treatment with the EHMT1/2 inhibitor UNC0642 or knockdown of EHMT1/2 in PFC induced a robust rescue of autism-like social deficits in Shank3-deficient mice, and restored NMDAR-mediated synaptic function. Activityregulated cytoskeleton-associated protein (Arc) was identified as one of the causal factors underlying the rescuing effects of UNC0642 on NMDAR function and social behaviors in Shank3-deficient mice. UNC0642 treatment also restored a large set of genes involved in neural signaling in PFC of Shank3-deficient mice. These results suggest that targeting histone methylation enzymes to adjust gene expression and ameliorate synaptic defects could be a potential therapeutic strategy for autism.
Project description:Kurozu is a traditional Japanese rice vinegar. During fermentation and aging of the Kurozu liquid in an earthenware jar over 1 year, solid residue called Kurozu Moromi is produced. In the present study, we evaluated whether concentrated Kurozu or Kurozu Moromi could ameliorate cognitive dysfunction in the senescence accelerated P8 mouse. Senescence accelerated P8 mice were fed 0.25% (w/w) concentrated Kurozu or 0.5% (w/w) Kurozu Moromi for 4 or 25 weeks. Kurozu suppressed cognitive dysfunction and amyloid accumulation in the brain, while Kurozu Moromi showed a tendency to ameliorate cognitive dysfunction, but the effect was not significant. We hypothesize that concentrated Kurozu has an antioxidant effect, however, the level of lipid peroxidation in the brain did not differ in senescence accelerated P8 mice. DNA microarray analysis indicated that concentrated Kurozu increased HSPA1A mRNA expression, a protein that prevents protein misfolding and aggregation. The increase in HSPA1A expression by Kurozu was confirmed using quantitative real-time PCR and immunoblotting methods. Therefore, the suppression of amyloid accumulation by concentrated Kurozu may be associated with HSPA1A induction. However, concentrated Kurozu could not increase HSPA1A expression in mouse primary neurons, suggesting it may not directly affect neurons.
Project description:Kurozu is a traditional Japanese rice vinegar. During fermentation and aging of the Kurozu liquid in an earthenware jar over 1 year, solid residue called Kurozu Moromi is produced. In the present study, we evaluated whether concentrated Kurozu or Kurozu Moromi could ameliorate cognitive dysfunction in the senescence accelerated P8 mouse. Senescence accelerated P8 mice were fed 0.25% (w/w) concentrated Kurozu or 0.5% (w/w) Kurozu Moromi for 4 or 25 weeks. Kurozu suppressed cognitive dysfunction and amyloid accumulation in the brain, while Kurozu Moromi showed a tendency to ameliorate cognitive dysfunction, but the effect was not significant. We hypothesize that concentrated Kurozu has an antioxidant effect, however, the level of lipid peroxidation in the brain did not differ in senescence accelerated P8 mice. DNA microarray analysis indicated that concentrated Kurozu increased HSPA1A mRNA expression, a protein that prevents protein misfolding and aggregation. The increase in HSPA1A expression by Kurozu was confirmed using quantitative real-time PCR and immunoblotting methods. Therefore, the suppression of amyloid accumulation by concentrated Kurozu may be associated with HSPA1A induction. However, concentrated Kurozu could not increase HSPA1A expression in mouse primary neurons, suggesting it may not directly affect neurons. Ten-times concentrated Kurozu (CK) was made from Kurozu liquid (Sakamoto Kurozu, Fukuyama, Kagoshima, Japan) by repeated vacuum distillation. The CK diet included 0.25% (w/w) CK in CE-2 basic rodent diet (Nihon CLEA, Tokyo, Japan). Senescence resistance (R1) and senescence accelerated P8 (P8) mice were purchased from Japan SLC (Shizuoka, Japan). Mice were housed at 25±2°C with 55±10% humidity on a 12-h light/dark cycle (lighting time 08:00-20:00). All mice were housed in independent cages and had free access to food and water. All procedures were compliant with the guidelines of the Kagoshima University Animal Ethics Committee (A10030). Ten-week old R1 mice (n=16) were fed a control CE2 diet and P8 mice were divided into three groups as follows: control CE2 diet group (n=9), KM diet group (n=9) or CK diet group (n=9). Feeding of the experimental diet started from 12 weeks of age until sacrificed. All mice were sacrificed under anesthesia at 17 weeks old (4 months old). The left side of the hippocampus region was excised from brains of 4 mice selected at random in each group, and then subjected to microarray analysis.
Project description:Arid1b is a chromatin remodeler implicated in neurodevelopmental disorders. Arid1b mutant mice with haploinsufficiency (Arid1b HT) displayed persistent excitatory synaptic dysfunction from juvenile to adult stage, decreased synaptic density and transmission. Moreover, they showed autistic-like behaviors in both of early and adult stages, decreased sociability in pup USV calling and adult social interaction, and adult repetitive grooming. To investigate pup stage transcriptomic changes in Arid1b mutant mice, RNAseq analysis of whole brain from wild-type and Arid1b mutant mice at postnatal day 3 was done. Transcriptomic changes support these electrophysiological and behavioral deficits. Arid1b HT mice at postnatal day 3 showed alterations in genes implicated in synaptic functions and ASD.
Project description:Arid1b is a chromatin remodeler implicated in neurodevelopmental disorders. Arid1b mutant mice with haploinsufficiency (Arid1b HT) displayed persistent excitatory synaptic dysfunction from juvenile to adult stage, decreased synaptic density and transmission. Moreover, they showed autistic-like behaviors in both of early and adult stages, decreased sociability in pup USV calling and adult social interaction, and adult repetitive grooming. To investigate early transcriptomic changes in Arid1b mutant mice, RNAseq analysis of prefrontal cortex from wild-type and Arid1b mutant mice at postnatal day 10 was done. Transcriptomic changes support these electrophysiological and behavioral deficits. Arid1b HT mice at postnatal day 10 showed alterations in genes implicated in synaptic functions and ASD.
Project description:Mutations in the X-linked solute carrier family 6-member (Slc6a8) gene, encoding the protein responsible for cellular creatine (Cr) uptake, cause Creatine Transporter Deficiency (CTD), an X-linked neurometabolic disorder presenting with cognitive dysfunction, autistic-like features, and epilepsy. The pathological determinants of CTD are still poorly understood and this lack of knowledge might hinder the development of therapeutic strategies. Here, we show that Cr deficiency perturbs gene expression in excitatory neurons, inhibitory cells and oligodendrocytes, inducing a remodeling of circuit excitability and synaptic wiring, while no effects are present in astrocytes and endothelial cells. We also describe specific alterations of high-energy demanding, Parvalbumin-expressing (PV+) interneurons, exhibiting a reduction in cellular and synaptic density, and a hypofunctional phenotype, affecting initiation, kinetics and frequency of action potentials. Mice lacking Slc6a8 only in PV+ neurons recapitulate numerous CTD features, such as cognitive deterioration, impaired cortical processing and hyperexcitability of brain circuits, demonstrating that Cr deficit in PV+ cells is sufficient to determine the CTD neurological endophenotype. Moreover, a pharmacological treatment targeted to restore the efficiency of PV+ synapses induces a significant improvement of cortical activity in Slc6a8 knock-out animals. Altogether, these data establish that Slc6a8 is critical for the normal function of PV+ interneurons and that a subtle dysfunction of these cells is critical for the disease pathogenesis, suggesting a novel therapeutic venue for CTD.
Project description:In this study, we investigate whether individual granulin subunits derived from the precursor protein progranulin are beneficial. We test this by asking if delivery of a single granulin to the brains of a preclinical model of FTD-GRN Grn-/-mice is sufficient to ameliorate disease-like phenotypes. We performed intracerebroventricular injections of recombinant adeno-associated virus (rAAV2/1) encoding granulin-2, granulin-4, full-length PGRN or GFP in neonatal Grn+/+ and Grn-/- mice. Following AAV injections, mice were aged for 12 months, tissues collected, and analyzed. Quantitative proteomics of the thalamus identified lysosomal function and neuroinflammation as pathways ameliorated by the expression of granulins. Biochemical markers of lysosomal dysfunction, neuroinflammation, and disease-like pathology were assessed via immunoblot and immunohistochemistry. We found that both granulin-2 and granulin-4 rescue markers of lysosomal dysfunction and neuroinflammation in cortical, hippocampal, and thalamic tissue.