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With a large database, we aimed to evaluate sex-specific distinctive changes in brain glucose metabolism and morphology during normal aging using MRI and 18 F-FDG PET. Methods: A total of 963 cognitively healthy adults were included in this study. All subjects completed a medical questionnaire, took the mini-mental state examination, and underwent brain MRI and whole-body 18 F-FDG PET. The MR and PET images were statistically analyzed using 3-dimensional stereotactic surface projection. All images were corrected for whole-brain pixel value to identify the brain regions with significant changes, and regions of interest were set up with reference to Brodmann areas. We evaluated morphologic and glucose metabolic changes by cross-sectional analysis. The baseline database consisted of subjects from 30 to 40 y old, and the age-step for comparison was 5-y ranges. We also compared sex-specific differences in MR and PET images in each age group. Results: Regarding age-related changes, in both sexes brain atrophy was observed in the lateral frontal and parietal regions and glucose hypometabolism in the medial frontal regions. There were significant differences in these parameters between the sexes; parallel changes in volume and metabolism were manifested in the medial frontal cortex in men and in the lateral and medial temporal cortex in women. By contrast, metabolism-dominant reductions were manifested in the lateral and medial parietal cortex in men and in the ventrolateral prefrontal cortex, including the Broca area, in women. These differences became insignificant in individuals 66 y or older. Conclusion: Our brain mapping study with a large number of reference human brain data demonstrated age-related parallel changes between morphology and metabolism in the medial frontal regions and sex-specific hypometabolism in the parietal (male) and ventrolateral prefrontal (female) cortices. These findings may suggest an aging vulnerability in sex-specific brain regions: the parietal cortex for visuospatial ability in men and the Broca area for speech processing in women. The current trend of an increase in the number of dementia patients, including those with Alzheimer disease (AD) (1), as well as the revised criteria for the diagnosis of dementia by the National Institute on Aging and the Alzheimer's Association (2-5), has brought researchers to place greater attention on early, preclinical, detection of changes in brain physiology. Indeed, in familial AD, pathologic changes in the brain seem to develop 25 y before the onset of clinical symptoms (6).To detect the preclinical stage of AD, it is necessary to catch subtle deviations from the healthy brain and, thus, to know the morphology and activity of a healthy brain for comparison. Several studies have used MRI or PET on cognitively normal people to evaluate age-related changes and sex-specific differences in the brain. To the best of our knowledge, however, the sexspecific differences in brain morphology and metabolism found by previous brain imaging studies were only in ...

The transcriptional coactivator with a PDZ-binding motif (TAZ) cooperates with various transcriptional factors and plays various roles. Immortalized human mammalian epithelial MCF10A cells form spheres when TAZ is overexpressed and activated. We developed a cell-based assay using sphere formation by TAZ-expressing MCF10A cells as a readout to screen 18,458 chemical compounds for TAZ activators. Fifty compounds were obtained, and 47 were confirmed to activate the TAZ-dependent TEADresponsive reporter activity in HEK293 cells. We used the derived subset of compounds as a TAZ activator candidate minilibrary and searched for compounds that promote myogenesis in mouse C2C12 myoblast cells. In this study, we focused on one compound, IBS008738. IBS008738 stabilizes TAZ, increases the unphosphorylated TAZ level, enhances the association of MyoD with the myogenin promoter, upregulates MyoD-dependent gene transcription, and competes with myostatin in C2C12 cells. TAZ knockdown verifies that the effect of IBS008738 depends on endogenous TAZ in C2C12 cells. IBS008738 facilitates muscle repair in cardiotoxin-induced muscle injury and prevents dexamethasone-induced muscle atrophy. Thus, this cell-based assay is useful to identify TAZ activators with a variety of cellular outputs. Our findings also support the idea that TAZ is a potential therapeutic target for muscle atrophy.

Our study strongly suggests that COX-2 can be one of the molecular targets in treating various skin and oral diseases. The results from our in vitro experiments also prompt us to develop a new protocol with a combination of COX-2 selective inhibitor and ALA-based PDT for more effective treatment of those diseases.

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Transcranial direct-current stimulation (tDCS) to the dorsolateral prefrontal cortex (DLPFC) has been established as an effective and noninvasive method to modulate cognitive function. Nevertheless, the mechanisms causing those cognitive changes under the tDCS remain largely unknown. We strove to elucidate the cognito-biological relation under the tDCS condition by examining whether the dopamine system activated by tDCS is involved in cognitive changes in human participants, or not. To evaluate the dopamine system, we used [11C]-raclopride positron emission tomography (PET) scanning: 20 healthy men underwent two [11C]-raclopride PET scans and subsequent neuropsychological tests. One scan was conducted after tDCS to the DLPFC. One was conducted after sham stimulation (control). Results of [11C]-raclopride PET measurements demonstrate that tDCS to the DLPFC caused dopamine release in the right ventral striatum. Neuropsychological tests for attentiveness revealed that tDCS to the DLPFC-enhanced participants’ accuracy. Moreover, this effect was correlated significantly with dopamine release. This finding provides clinico-biological evidence, demonstrating that enhancement of dopamine signaling by tDCS in the ventral striatum is associated with attention enhancement.