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Tajinda, K.

Publications and source records attributed to Tajinda, K..

3 recordsLinked to original sources

Repetitive Neuronal Activation Regulates Cellular Maturation State via Nuclear Reprogramming

Neural stimulation, such as electroconvulsive therapy (ECT) and repetitive transcranial magnetic stimulation (rTMS), are highly effective clinical interventions for a broad spectrum of psychiatric disorders, including depression and schizophrenia. However, their mechanism of action at the cellular level remains poorly understood. Here, we modelled ECT with repeated optogenetic neuronal stimulation in the mouse dentate gyrus, and observed ECT-like behavioral effects, including decreased depression-like behavior and increased locomotor activity. At the cellular level, we found dematuration to a long-term stable state, persisting for more than one month, defined by changes in nuclear structure, gene expression patterns resembling the G2/M phase of the cell cycle, and altered neural coding of navigational information. Moreover, knockout of the G2/M master regulator Cyclin B rescued some of behavioral and cellular effects. These findings demonstrate that ECT-like brain stimulation triggers plasticity of the cellular state, revealing a form of stimulus-regulated nuclear reprogramming with potential clinical utility.

neuroscience↗

Cell type-specific genetic regulation of expression in the granule cell layer of the human dentate gyrus

Laser capture microdissection followed by RNA-seq (LCM-seq) was used to profile the transcriptional landscape of the granule cell layer of the dentate gyrus (DG-GCL) in human hippocampus, and contrasted to homogenate tissue. We identified widespread cell type-specific aging and genetic effects in the DG-GCL that were either missing or directionally discordant in corresponding bulk hippocampus RNA-seq data from largely the same subjects. Of the [~]9 million eQTLs in the DG-GCL, 15% were not in bulk hippocampus, including 15 schizophrenia genome-wide association study (GWAS) risk variants. We then created custom transcriptome-wide association study (TWAS) genetic weights from the DG-GCL which identified many novel schizophrenia-associated genetic signals not found in TWAS from bulk hippocampus, including GRM3 and CACNA1C. These results highlight the biological resolution of cell type-specific expression profiling using targeted sampling strategies like LCM, and complement homogenate and single nuclei approaches in human brain.

neuroscience↗

Transdiagnostic characterization of neuropsychiatric disorders by hyperexcitation-induced immaturity

Biomarkers are needed to improve the diagnosis of neuropsychiatric disorders. Promising candidates are imbalance of excitation and inhibition in the brain, and maturation abnormalities. Here, we characterized different disease conditions by mapping changes in the expression patterns of maturation-related genes whose expression was altered by experimental neural hyperexcitation in published studies. This revealed two gene expression patterns: decreases in maturity markers and increases in immaturity markers. These two groups of genes were characterized by the overrepresentation of genes related to synaptic function and chromosomal modification, respectively. We used these two groups in a transdiagnostic analysis of 80 disease datasets for eight neuropsychiatric disorders and 12 datasets from corresponding animal models, and found that transcriptomic pseudoimmaturity inducible by neural hyperexcitation is shared by multiple neuropsychiatric disorders, such as schizophrenia, Alzheimer disorders, and ALS. Our results indicate that this endophenotype serve as a basis for transdiagnostic characterization of these disorders.

neuroscience↗