母子分離ストレスが報酬探索行動に及ぼす影響と側坐核におけるドーパミンD1受容体のDNAのメチル化機構を介した発現変化について

Early-life stress has long-lasting effects on the stress response, emotions, and behavior throughout an individual’s life. Clinical reports have demonstrated that child abuse victims exhibit impairments in reward-associated behavior; yet, the mechanism for this effect remains unclear. Maternal separation (MS) or MS coupled with social isolation (SI) (MS + SI) is widely used as a model for early-life stress in rodent studies. We employed mice subjected to MS + SI to clarify the long-term effect of early-life stress on reward-seeking involving palatable foods by a conditioned place-preference (CPP) paradigm. Prior MS + SI experience decreased exploration time in a chocolate-paired compartment in adult female mice, but not in male mice. We then focused on the mesolimbic dopamine pathway associated with reward-seeking behavior and measured both mRNA and protein levels of tyrosine hydroxylase (TH) in the ventral tegmental area (VTA) and dopamine D1 and D2 receptors in the nucleus accumbens (NAc). MS + SI female mice had significantly lower D1 receptor mRNA and protein levels than controls, whereas the expression of TH and the D2 receptor was similar in the 2 groups. All mRNA and protein levels were unchanged in MS + SI male mice. When attempting to elucidate the mechanism underlying downregulation of the D1 receptor in the NAc of MS + SI females, we found hypermethylation of the Drd1a promoter region. These results suggest that early-life stress affects reward-seeking behavior in female mice, which may be associated with the downregulation of D1 receptor in the NAc via epigenetic modification of its promoter region.博士（医学）・甲第672号・平成29年6月28日Copyright © 2017 Elsevier B.V. All rights reserved

An Analysis of Factors that Exacerbate Asthma, Based on a Japanese Questionnaire

ABSTRACTBackgroundIt is known that a wide variety of factors exacerbate asthma; however, few studies have investigated the factors that exacerbate asthma from a patient's perspective. The aim of this study was to analyze the factors that exacerbate asthma, based on a questionnaire completed by asthma patients in Niigata Prefecture.MethodsBased on questionnaires given to 3085 patients who visited the medical institutes in the Niigata Prefecture monthly from September through October 2006, groups stratified by sex, age, disease type and disease severity, were analyzed for factors contributing to asthma exacerbation, as described in the guideline of the Japanese Society of Allergology.ResultsThe leading exacerbating factor chosen by patients was a change in the weather, followed by smoking, allergen exposure, fatigue, stimulants, and air pollutants. Respiratory infection, widely recognized as a critical factor of severe exacerbation, was ranked seventh. Allergen exposure and air pollutants were prominent in younger individuals, whereas respiratory infection tended to be more common in elderly subjects. Allergen exposure, air pollutants, and exercise were significantly more common in atopic-type patients, in contrast with respiratory infection in non-atopic-type patients. According to multiple regression analysis, poor asthma control during the last one year was associated with changes in the weather, whereas the non-atopic disease type was related to exacerbation by respiratory infection. Current smoking was associated with both factors.ConclusionsMany factors exacerbate asthma, depending on the individual case and his/her background. These data suggest that changes in the weather may be more important factor for patients in asthma exacerbation

骨髄間葉系細胞シートはラット脊髄離断損傷後にグリア瘢痕形成を抑制し、軸索再生と後肢運動機能改善を促進する。

OBJECTIVE Transplantation of bone marrow stromal cells (BMSCs) is a theoretical potential as a therapeutic strategy in the treatment of spinal cord injury (SCI). Although a scaffold is sometimes used for retaining transplanted cells in damaged tissue, it is also known to induce redundant immunoreactions during the degradation processes. In this study, the authors prepared cell sheets made of BMSCs, which are transplantable without a scaffold, and investigated their effects on axonal regeneration, glial scar formation, and functional recovery in a completely transected SCI model in rats. METHODS BMSC sheets were prepared from the bone marrow of female Fischer 344 rats using ascorbic acid and were cryopreserved until the day of transplantation. A gelatin sponge (GS), as a control, or BMSC sheet was transplanted into a 2-mm-sized defect of the spinal cord at the T-8 level. Axonal regeneration and glial scar formation were assessed 2 and 8 weeks after transplantation by immunohistochemical analyses using anti-Tuj1 and glial fibrillary acidic protein (GFAP) antibodies, respectively. Locomotor function was evaluated using the Basso, Beattie, and Bresnahan scale. RESULTS The BMSC sheets promoted axonal regeneration at 2 weeks after transplantation, but there was no significant difference in the number of Tuj1-positive axons between the sheet- and GS-transplanted groups. At 8 weeks after transplantation, Tuj1-positive axons elongated across the sheet, and their numbers were significantly greater in the sheet group than in the GS group. The areas of GFAP-positive glial scars in the sheet group were significantly reduced compared with those of the GS group at both time points. Finally, hindlimb locomotor function was ameliorated in the sheet group at 4 and 8 weeks after transplantation. CONCLUSIONS The results of the present study indicate that an ascorbic acid-induced BMSC sheet is effective in the treatment of SCI and enables autologous transplantation without requiring a scaffold.博士（医学）・甲第656号・平成28年11月24日© Copyright 2016 American Association of Neurological SurgeonsThe definitive version is available at " http://dx.doi.org/10.3171/2016.8.SPINE16250

Involvement of SIK3 in Glucose and Lipid Homeostasis in Mice

Salt-inducible kinase 3 (SIK3), an AMP-activated protein kinase-related kinase, is induced in the murine liver after the consumption of a diet rich in fat, sucrose, and cholesterol. To examine whether SIK3 can modulate glucose and lipid metabolism in the liver, we analyzed phenotypes of SIK3-deficent mice. Sik3−/− mice have a malnourished the phenotype (i.e., lipodystrophy, hypolipidemia, hypoglycemia, and hyper-insulin sensitivity) accompanied by cholestasis and cholelithiasis. The hypoglycemic and hyper-insulin-sensitive phenotypes may be due to reduced energy storage, which is represented by the low expression levels of mRNA for components of the fatty acid synthesis pathways in the liver. The biliary disorders in Sik3−/− mice are associated with the dysregulation of gene expression programs that respond to nutritional stresses and are probably regulated by nuclear receptors. Retinoic acid plays a role in cholesterol and bile acid homeostasis, wheras ALDH1a which produces retinoic acid, is expressed at low levels in Sik3−/− mice. Lipid metabolism disorders in Sik3−/− mice are ameliorated by the treatment with 9-cis-retinoic acid. In conclusion, SIK3 is a novel energy regulator that modulates cholesterol and bile acid metabolism by coupling with retinoid metabolism, and may alter the size of energy storage in mice

Sick Sinus Syndrome Mimicking Autonomic Dysfunction of Dementia With Lewy Bodies

Dementia with Lewy bodies (DLB) is recognized as the second most common form of dementia in aged people. It is well known that patients with DLB often develop various autonomic symptoms. Here, we present a case in which there was sick sinus syndrome mimicking the DLB-related autonomic dysfunctions. After the pacemaker implantation, the patient's symptom perfectly extinguished. It is essential for psychiatrists or other professionals who are mainly seeing dementia patients to rule out critical causes that may mimic autonomic symptoms in patients with DUB