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Kishimoto, Y.

Publications and source records attributed to Kishimoto, Y..

4 recordsLinked to original sources

Dysregulated expanded endocannabinoid system as therapeutic targets of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by the selective loss of upper and lower motor neurons. ALS patients often manifest systemic metabolic abnormalities such as glucose intolerance. Herein, to elucidate the systemic metabolic changes related to ALS progression, we performed metabolomics analysis on the serum of ALS patients and identified several metabolites associated with the disease progression, including metabolites involved in the expanded endocannabinoid system (ECS). In particular, the levels of N-acyl taurines (NAT) were correlated with the longitudinal change in the revised ALS functional rating scale (ALSFRS-R) rating. In vitro experiments with ALS cell models and in vivo studies with SOD1G93A transgenic mice revealed that PF-04457845, a fatty amide acid hydrolase (FAAH) inhibitor, up-regulated the expanded ECS, particularly the levels of NATs and N-acyl ethanolamine and ameliorates motor neuron degeneration through the regulation of microglial polarization, synapse plasticity, and neuronal development. Our study indicates that dysregulation of the expanded ECS is associated with ALS progression and a target for novel disease-modifying therapies.

neuroscience↗

Transcriptomic Landscape of Hyperthyroidism in Mice Overexpressing Thyroid Stimulating Hormone

Hyperthyroidism is a condition with excessive thyroid hormone secretion. Activation of thyroid stimulating hormone receptor (TSHR) fundamentally leads to hyperthyroidism. The details of TSHR signaling remain to be elucidated. We conducted transcriptome analyses for hyperthyroid mice that we generated by overexpressing TSH. TSH overexpression via hydrodynamic gene delivery with pLIVE-TSHB and pLIVE-CGA vectors consistently caused hyperthyroidism and goiters for at least 4 weeks in C57BL/6J mice. RNA sequencing analysis of their thyroid glands revealed that thiamazole slightly changed the thyroid transcriptome, which reinforces a conventional theory that thiamazole decreases thyroid hormone secretion via inhibition of thyroid peroxidase activity. Meanwhile, TSH overexpression drastically changed the thyroid transcriptome. In particular, enrichment analyses identified the cell cycle, phosphatidylinositol-3 kinase/Akt pathway, and Ras-related protein 1 pathway as possibly associated with goiter development. Regarding the role of TSHR signaling in hyperthyroidism, it is noteworthy that Slc26a4 was exclusively upregulated among genes crucial to thyroid hormone secretion at both 1 and 4 weeks after hydrodynamic gene delivery. To verify the relationship between this upregulation and hyperthyroidism, we overexpressed TSH in Slc26a4 knockout mice. TSH overexpression caused hyperthyroidism in Slc26a4 knockout mice, equivalent to that in control mice. To summarize, we analyzed hyperthyroid mice generated by TSH overexpression. We did not observe significant changes in known genes and pathways involved in thyroid hormone secretion. Thus, our datasets might include candidate genes that have not yet been identified as regulators of thyroid function. Our transcriptome datasets regarding hyperthyroidism can contribute to future research on TSHR signaling.

physiology↗

Depression-like state induced by low-frequency repetitive transcranial magnetic stimulation to ventral medial frontal cortex in monkeys

The medial frontal cortex (MFC), especially its ventral part, has long been of great interest with respect to the pathology of mood disorders. A number of human brain imaging studies have demonstrated the abnormalities of this brain region in patients with mood disorders, however, whether it is critically involved in the pathogenesis of such disorders remains to be fully elucidated. In this study, we conducted a causal study to investigate how the suppression of neural activity in the ventral region of the MFC (vMFC) affects the behavioral and physiological states of monkeys by using repetitive transcranial magnetic stimulation (rTMS). By using low-frequency rTMS (LF-rTMS) as an inhibitory intervention, we found that LF-rTMS targeting the vMFC induced a depression-like state in monkeys, which was characterized by a reduced spontaneous behavioral activity, increased plasma cortisol level, impaired sociability, and decreased motivation level. On the other hand, no such significant changes in behavioral and physiological states were observed when targeting the other MFC regions, dorsal or posterior. We further found that the administration of an antidepressant agent, ketamine, ameliorated the abnormal behavioral and physiological states induced by the LF-rTMS intervention. These findings indicate the causal involvement of the vMFC in the regulation of mood and affect and the validity of the LF-rTMS-induced dysfunction of the vMFC as a nonhuman primate model of the depression-like state.

neuroscience↗

Ets2 frame-shift mutant models express in-frame mRNA by exon skipping that complements Ets2 function in the skin

The Ets2 transcription factor has been implicated in various biological processes. An Ets2 mutant model, which lacks the DNA-binding domain (ETS domain), was previously reported to exhibit embryonic lethality caused by a trophoblast abnormality. This phenotype could be rescued by tetraploid complementation, resulting in pups with wavy hair. Here, we generated new Ets2 mutant models with deletions in exon 8 and with frame-shift mutations using the CRISPR/Cas9 method. Homozygous mutants could not be obtained by natural mating as previously reported. After rescuing with tetraploid complementation, homozygous mutant mice were generated, but these mice did not exhibit wavy hair phenotype. Our newly generated mice exhibited exon 8 skipping, which led to in-frame mutant mRNA expression in the skin and thymus but not in E7.5 embryos. As this in-frame mutation contained the ETS domain, the exon 8-skipped Ets2 mRNA was likely translated into protein in the skin that complemented the Ets2 function. Thus, these Ets2 mutant models, depending on the cell types, exhibited novel phenotypes due to exon skipping and are expected to be useful in several fields of research. Summary statementNew Ets2 mutant models showed embryonic lethal phenotype by a placental abnormality but did not exhibit a wavy hair phenotype as a previous model.

developmental biology↗