1.High-Fat Diet-Fed Kcnq1 Mutant Mice Have Reduced Pancreatic β-Cell Mass via Gene-Environment Interaction
Shun-ichiro ASAHARA ; Hiroyuki INOUE ; Yuka IHARA ; Kyoko TERUYAMA ; Asuka IMAI ; Chisako HARA ; Mizuki HARA ; Masako SEIKE ; Aisha YOKOI ; Nozomi KIDO ; Hirotaka SUZUKI ; Ayumi KANNO ; Yuka INABA ; Hitoshi WATANABE ; Go SHIOI ; Maki KIMURA-KOYANAGI ; Michihiro MATSUMOTO ; Hiroshi INOUE ; Keiichi I. NAKAYAMA ; Wataru OGAWA ; Masato KASUGA ; Yoshiaki KIDO
Diabetes & Metabolism Journal 2026;50(1):77-89
Background:
The potassium voltage-gated channel subfamily Q member 1 (KCNQ1) gene has recently received much attention as a candidate susceptibility gene for type 2 diabetes mellitus, especially in Asian populations. We previously reported that Kcnq1 mutant mice exhibit reduced insulin secretion and hyperglycemia due to a decrease in pancreatic β-cell mass. Through in vivo and in vitro analyses, we ascertained that this mechanism is the result of the downregulation of the non-coding RNA ‘Kcnq1ot1,’ which is expressed in the paternal allele of the Kcnq1 gene region, causing an increase in the expression of the cell cycle inhibitor cyclin dependent kinase inhibitor 1C (Cdkn1c). It was found that decreased Kcnq1ot1 expression resulted in pancreatic β-cell failure; however, the degree of pancreatic β-cell volume reduction was not severe.
Methods:
We induced obesity in Kcnq1ot1 truncation mice by feeding them a high-fat diet and evaluated pancreatic β-cell mass.
Results:
In the present study, we reveal that CCAAT/enhancer binding protein beta (C/EBPβ), which is expressed at higher levels in pancreatic β-cells in obese individuals, further increases the expression of Cdkn1c, which is upregulated by the Kcnq1 gene mutation. We found that simultaneous Cdkn1c hypomethylation and C/EBPβ overexpression in pancreatic β-cells causes a synergistic decrease in pancreatic β-cell mass.
Conclusion
This finding suggests that the synergistic effect of genetic factors such as Kcnq1 gene mutations and environmental factors such as obesity and overeating, which lead to increased expression of C/EBPβ, contribute to the regulation of pancreatic β-cell mass. This study is the first to show that the Kcnq1 gene is related to pancreatic β-cell mass through genetic-environment interactions.
2.Di(2-ethylhexyl) phthalate-induced toxicity and peroxisome proliferator-activated receptor alpha: a review.
Yuki ITO ; Michihiro KAMIJIMA ; Tamie NAKAJIMA
Environmental Health and Preventive Medicine 2019;24(1):47-47
The plasticizer di(2-ethylhexyl) phthalate (DEHP) has been widely used in the manufacture of polyvinyl chloride-containing products such as medical and consumer goods. Humans can easily be exposed to it because DEHP is ubiquitous in the environment. Recent research on the adverse effects of DEHP has focused on reproductive and developmental toxicity in rodents and/or humans. DEHP is a representative of the peroxisome proliferators. Therefore, peroxisome proliferator-activated receptor alpha (PPARα)-dependent pathways are the expected mode of action of several kinds of DEHP-induced toxicities. In this review, we summarize DEHP kinetics and its mechanisms of carcinogenicity and reproductive and developmental toxicity in relation to PPARα. Additionally, we give an overview of the impacts of science policy on exposure sources.
Animals
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Diethylhexyl Phthalate
;
toxicity
;
Environmental Pollutants
;
toxicity
;
Haplorhini
;
Humans
;
Mice
;
PPAR alpha
;
genetics
;
metabolism
;
Plasticizers
;
toxicity
;
Rats
3.A Prospective Multicenter Study Evaluating Bleeding Risk after Endoscopic Ultrasound-Guided Fine Needle Aspiration in Patients Prescribed Antithrombotic Agents.
Kazumichi KAWAKUBO ; Kei YANE ; Kazunori ETO ; Hirotoshi ISHIWATARI ; Nobuyuki EHIRA ; Shin HABA ; Ryusuke MATSUMOTO ; Keisuke SHINADA ; Hiroaki YAMATO ; Taiki KUDO ; Manabu ONODERA ; Toshinori OKUDA ; Yoko TAYA-ABE ; Shuhei KAWAHATA ; Kimitoshi KUBO ; Yoshimasa KUBOTA ; Masaki KUWATANI ; Hiroshi KAWAKAMI ; Akio KATANUMA ; Michihiro ONO ; Tsuyoshi HAYASHI ; Minoru UEBAYASHI ; Naoya SAKAMOTO
Gut and Liver 2018;12(3):353-359
BACKGROUND/AIMS: Although the risk of bleeding after endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is low, the safety of EUS-FNA in patients prescribed antithrom-botic agents is unclear. Therefore, this study evaluated the incidence of bleeding after EUS-FNA in those patients. METHODS: Between September 2012 and September 2015, patients who were prescribed antithrombotic agents underwent EUS-FNA at 13 institutions in Japan were prospectively enrolled in the study. The antithrombotic agents were managed according to the guidelines of the Japanese Gastrointestinal Endoscopy Society. The rate of bleeding events, thromboembolic events and other complications within 2 weeks after EUS-FNA were analyzed. RESULTS: Of the 2,629 patients who underwent EUS-FNA during the study period, 85 (62 males; median age, 74 years) patients were included in this stduy. Two patients (2.4%; 95% confidence interval [CI], 0.6% to 8.3%) experienced bleeding events. One patient required surgical intervention for hemothorax 5 hours after EUS-FNA, and the other experienced melena 8 days after EUS-FNA and required red blood cell transfusions. No thromboembolic events occurred (0%; 95% CI, 0.0% to 4.4%). Three patients (3.5%; 95% CI, 1.2% to 10.0%) experienced peri-puncture abscess formation. CONCLUSIONS: The rate of bleeding after EUS-FNA in patients prescribed antithrombotic agents might be considerable.
Abscess
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Asian Continental Ancestry Group
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Endoscopic Ultrasound-Guided Fine Needle Aspiration*
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Endoscopy, Gastrointestinal
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Erythrocyte Transfusion
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Fibrinolytic Agents*
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Hemorrhage*
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Hemothorax
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Humans
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Incidence
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Japan
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Male
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Melena
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Prospective Studies*

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