Publishing type：Research paper (scientific journal)   International / domestic magazine：International journal  

While hypothalamic leptin resistance can occur prior to establishment of obesity, clarification is needed as to whether the impaired response to leptin in the reward-related nuclei occurs independently of obesity. To answer this question, we attempted to dissociate the normally coexisting leptin resistance from obesity. We investigated phenotypes of leptin-overexpressing transgenic mice fed for 1 week with 60 % high-fat diet (HFD) (LepTg-HFD1W mice). After 1 week, we observed that LepTg-HFD1W mice weighed as same as wild type (WT) mice fed standard chow diet (CD) for 1 week (WT-CD1W mice). However, compared to WT-CD1W mice, LepTg-HFD1W mice exhibited attenuated leptin-induced anorexia, decreased leptin-induced c-fos immunostaining in nucleus accumbens (NAc), one of important site of reward system, decreased leptin-stimulated pSTAT3 immunostaining in hypothalamus. Furthermore, neither sucrose nor lipid preference was suppressed by leptin in LepTg-HFD1W mice. On the contrary, leptin significantly suppressed both preferences in WT mice fed HFD (WT-HFD1 W mice). These results indicate that leptin responsiveness decreases in NAc independently of obesity. Additionally, in this situation, suppressive effect of leptin on the hedonic feeding results in impaired regulation. Such findings suggest the impaired leptin responsiveness in NAc partially contributes to dysregulated hedonic feeding behavior independently of obesity.

DOI： 10.1016/j.neures.2021.12.007

PubMed

Publishing type：Research paper (scientific journal)  

若年糖尿病患者の治療中断の予防,すなわち定期的な通院に関する支援は大きな課題である.定期的な通院は糖尿病のセルフケア行動の1つである.糖尿病のセルフケア行動には自己効力感やソーシャルサポートの関連が知られるが,近年ヘルスリテラシーとの関連が報告されている.そこで40歳未満成人2型糖尿病患者の治療中断率を明らかにし,治療中断とヘルスリテラシーの関連を自己効力感,ソーシャルサポート,経済状況を調整した多重ロジスティック回帰分析を行い検討した.調査は糖尿病専門医および糖尿病の専門資格を有する看護師が所属する大阪府内の13施設で行った.治療中断は,参加者の40%に認められた.治療中断にヘルスリテラシーは関連していなかった.定期的な受診を継続するために,40歳未満成人2型糖尿病患者で自己効力感が低く経済状況が厳しい患者に対しては,外来でのサポートを強化する必要がある.(著者抄録)

Other URL： https://search.jamas.or.jp/index.php?module=Default&action=Link&pub_year=2020&ichushi_jid=J00926&link_issn=&doc_id=20200609420002&doc_link_id=10.11213%2Ftonyobyo.63.324&url=https%3A%2F%2Fdoi.org%2F10.11213%2Ftonyobyo.63.324&type=J-STAGE&icon=https%3A%2F%2Fjk04.jamas.or.jp%2Ficon%2F00007_2.gif

Publishing type：Research paper (scientific journal)   International / domestic magazine：International journal  

Leptin is an adipocyte-derived anorexic hormone that exerts its effects via the hypothalamus and other brain regions, including the reward system. Leptin-deficient ob/ob mice that present morbid obesity, hyperphagia, insulin resistance, and infertility are one of the most investigated mouse models of obesity. Conditioned place preference (CPP) paradigm is a standard behavioral model to evaluate the rewarding value of substrates. While leptin is reported to decrease the CPP of lean mice for high fat diet (HFD), it is unknown how CPP toward HFD is affected by leptin replacement in the pathophysiological condition of ob/ob mice. In the present study, we performed the CPP test in order to clarify the effect of leptin on the preference of ob/ob mice for HFD. ob/ob mice had a significantly higher HFD preference in CPP test when compared with wild-type (WT) mice and this preference was suppressed to the levels comparable to the WT mice by leptin replacement with or without normalization of body weight. These results demonstrate that leptin decreases the reward value of HFD independently of obesity, suggesting that leptin reduces food intake by suppressing the hedonic feeding pathway in ob/ob mice. (C) 2017 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.neulet.2017.01.033

PubMed

Other URL： http://orcid.org/0000-0003-4378-4899

Publishing type：Research paper (scientific journal)   International / domestic magazine：International journal  

In this study, we evaluated the preventive effect of mazindol on the development of obesity and sought to elucidate the drug's effects on the reward system. In mice, body weight gain and hyperphagia induced by high-fat diet (HFD) were decreased by 38.6% and 13.9%, respectively, by subcutaneous infusion bf mazindol (1.5 mg/kg/day) for 28 days. A single intraperitoneal administration of mazindol (1.5 mg/kg) significantly reduced lipid preference, as assessed using the two-bottle preference paradigm (vehicle, 89.98 +/- 1.66%; mazindol, 75.65 +/- 5.47%; p < 0.05). In addition, the conditioned place preference (CPP) test demonstrated that mazindol (1.5 mg/kg) significantly decreased CPP score for HFD as compared with vehicle (vehicle, 330.44 +/- 58.61 s; mazindol, 144.72 +/- 43.02 s; p < 0.05). Moreover, at the dose required for these effects, mazindol did not elicit abuse potential or induce psychostimulant-like behavior. These results confirm that mazindol prevents diet-induced obesity without addictive behavior and demonstrate that its action is mediated at least in part via the reward system, advancing our understanding of mazindol in clinical practice. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.neulet.2016.09.014

PubMed

J-GLOBAL

Other URL： http://orcid.org/0000-0003-4378-4899

Publishing type：Research paper (scientific journal)  

Background: Color affects emotions, feelings, and behaviors. We hypothesized that color used in self-monitoring of blood glucose (SMBG) is helpful for patients to recognize and act on their glucose levels to improve glycemic control. Here, two color-indication methods, color record (CR) and color display (CD), were independently compared for their effects on glycemic control in less frequently insulin-treated type 2 diabetes.
Subjects and Methods: One hundred twenty outpatients were randomly allocated to four groups with 2 x 2 factorial design: CR or non-CR and CD or non-CD. Blood glucose levels were recorded in red or blue pencil in the CR arm, and a red or blue indicator light on the SMBG meter was lit in the CD arm, under hyperglycemia or hypoglycemia, respectively. The primary end point was difference in glycated hemoglobin (HbA1c) reduction in 24 weeks. Secondary end points were self-management performance change and psychological state change.
Results: HbA1c levels at 24 weeks were significantly decreased in the CR arm by -0.28% but were increased by 0.03% in the non-CR arm (P = 0.044). In addition, diet and exercise scores were significantly improved in the CR arm compared with the non-CR arm. The exercise score showed significant improvement in the CD arm compared with the non-CD arm but without a significant difference in HbA1c reduction. Changes in psychological states were not altered between the arms.
Conclusions: CR has a favorable effect on self-management performance without any influence on psychological stress, resulting in improved glycemic control in type 2 diabetes patients using less frequent insulin injection. Thus, active but not passive usage of color-indication methods by patients is important in successful SMBG.

DOI： 10.1089/dia.2013.0301

PubMed

J-GLOBAL

Other URL： http://orcid.org/0000-0003-4378-4899

SDGs：

Type：Seminar, workshop

Number of participants：15（人）