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Okauchi, T.

Publications and source records attributed to Okauchi, T..

2 recordsLinked to original sources

Novel plasmalogen derivative KIT-13 restores neurological function in a mouse model of Rett syndrome by reducing neuroinflammation and restoring mitochondrial function

Neurodevelopmental disorders, including Rett Syndrome (RTT), have no functional cure and cause substantial levels of disability. Neuroinflammation is now strongly associated with both neurodevelopmental disorders and neurodegenerative diseases, providing a strong rationale for development of novel therapeutics targeting common neuroinflammatory mechanisms. RTT is caused by mutations in the methylated DNA binding factor MECP2. Mecp2-deficient (Mecp2-KO) mice, which have been extensively characterized as a mouse model of RTT, exhibit high levels of neuroinflammation, mitochondrial dysfunction, and severe neurological symptoms similar to RTT patients. KIT-13 is a novel plasmalogen derivative being developed for the treatment of neurodevelopmental disorders including RTT. This study evaluated KIT-13 in both cell-based and in vivo models for its potential to inhibit neuroinflammation and address underlying mitochondrial dysfunction, as well as effects on RTT-like neurological symptoms in the RTT mouse model. Oral administration of KIT-13 to Mecp2-KO mice significantly reduced neurological symptoms assessed by a composite score evaluating mobility, gait, hindlimb clasping, tremor, breathing, and general condition and improved the life span of the RTT model mice. In addition, KIT-13 suppressed mitochondrial DNA leakage associated with Mecp2 deficiency, and significantly suppressed neuroinflammation as measured by microglial cell morphology. These results suggest that KIT-13 may be a promising therapeutic agent for RTT and other neuroinflammation-related diseases.

neuroscience↗

Acquisition of Auditory Discrimination Mediated by Different Processes through Two Distinct Circuits Linked to the Lateral Striatum

The striatum, the central hub of cortico-basal ganglia loops, contains functionally heterogeneous subregions distinguished by the topographic patterns of structural connectivity. These subregions mediate various processes of procedural learning. However, it remains unclear when and how striatal subregions engage in the acquisition of sensory stimulus-based decision-making. A neuroimaging of regional brain activity shows that the anterior dorsolateral striatum (aDLS) and posterior ventrolateral striatum (pVLS) in rats are activated in a different temporal pattern during the acquisition phase of auditory discrimination. Chronic and transient pharmacologic manipulations show that the aDLS promotes the behavioral strategy driven by the stimulus- response association while suppressing that by the response-outcome association, and that the pVLS contributes to forming and maintaining the stimulus-response strategy. Electrophysiological recording indicates that subpopulations of aDLS neurons predominantly represent the outcome of specific behaviors at the initial period of discrimination learning, and that pVLS subpopulations encode the beginning and ending of each behavior according to the progress of learning. In addition, other subpopulations of striatal neurons indicate sustained activation after obtaining reward with distinct patterns reflecting the stimulus-response associations. Our findings demonstrate that aDLS and pVLS neurons integrate the new learning of auditory discrimination in spatiotemporally and functionally different manners.

animal behavior and cognition↗