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Ito T. Molecular pathology of small cell lung cancer: Overview from studies on neuroendocrine differentiation regulated by ASCL1 and Notch signaling. Pathol Int 2024; 74:239-251. [PMID: 38607250 DOI: 10.1111/pin.13426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 03/20/2024] [Accepted: 03/24/2024] [Indexed: 04/13/2024]
Abstract
Pulmonary neuroendocrine (NE) cells are rare airway epithelial cells. The balance between Achaete-scute complex homolog 1 (ASCL1) and hairy and enhancer of split 1, one of the target molecules of the Notch signaling pathway, is crucial for NE differentiation. Small cell lung cancer (SCLC) is a highly aggressive lung tumor, characterized by rapid cell proliferation, a high metastatic potential, and the acquisition of resistance to treatment. The subtypes of SCLC are defined by the expression status of NE cell-lineage transcription factors, such as ASCL1, which roles are supported by SRY-box 2, insulinoma-associated protein 1, NK2 homeobox 1, and wingless-related integration site signaling. This network reinforces NE differentiation and may induce the characteristic morphology and chemosensitivity of SCLC. Notch signaling mediates cell-fate decisions, resulting in an NE to non-NE fate switch. The suppression of NE differentiation may change the histological type of SCLC to a non-SCLC morphology. In SCLC with NE differentiation, Notch signaling is typically inactive and genetically or epigenetically regulated. However, Notch signaling may be activated after chemotherapy, and, in concert with Yes-associated protein signaling and RE1-silencing transcription factor, suppresses NE differentiation, producing intratumor heterogeneity and chemoresistance. Accumulated information on the molecular mechanisms of SCLC will contribute to further advances in the control of this recalcitrant cancer.
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Grants
- 20H03691 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 18K19489 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 16590318 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 25460439 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- Smoking Research Foundation, Japan
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Affiliation(s)
- Takaaki Ito
- Department of Medical Technology, Kumamoto Health Science University Faculty of Health Sciences, Kumamoto, Japan
- Department of Pathology and Experimental Medicine, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan
- Department of Brain Morphogenesis, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
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2
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Son BK, Lyu W, Tanaka T, Yoshizawa Y, Akishita M, Iijima K. Impact of the anti-inflammatory diet on serum high-sensitivity C-Reactive protein and new-onset frailty in community-dwelling older adults: A 7-year follow-up of the Kashiwa cohort study. Geriatr Gerontol Int 2024; 24 Suppl 1:189-195. [PMID: 38126695 DOI: 10.1111/ggi.14781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 11/21/2023] [Accepted: 11/22/2023] [Indexed: 12/23/2023]
Abstract
AIM Chronic inflammation is a pathophysiological cause of age-related diseases, including frailty. Although diet is a determinant of inflammation, few prospective studies have investigated its role in frailty onset. This study used the dietary inflammatory index to investigate whether a proinflammatory diet affects the incidence of frailty in a 7-year follow-up of older Japanese adults. METHODS We enrolled community-dwelling older adults without frailty from the 2014 Kashiwa cohort study. Energy-adjusted dietary inflammatory index (E-DII) scores were calculated using a brief self-administered diet history questionnaire. Serum high-sensitivity C-reactive protein (hsCRP) levels were measured by immunoassays. Frailty was defined as meeting three of Fried's five phenotypic criteria. Cox regression was used to analyze associations between E-DII scores and new-onset frailty after adjusting for relevant confounders. RESULTS Overall, 95 (11.7%) of 811 participants (73.7 ± 4.8 years, women 47.3%) developed new-onset frailty during the 7-year follow-up. The baseline E-DII scores significantly correlated with log-hsCRP levels, even after adjustment (β = 0.075, P = 0.035). The highest tertile of E-DII scores (proinflammatory diet) showed a 2.03 times (95% confidence interval, 1.22-3.36) higher risk of new-onset frailty than that associated with the lowest tertile (P = 0.006). When E-DII was calculated on the basis of anti-inflammatory food parameters only, the highest tertile showed a 2.32 times (95% confidence interval, 1.36-3.95) higher risk than that associated with the lowest tertile (P = 0.002). CONCLUSIONS E-DII scores significantly correlated with serum hsCRP levels. High E-DII scores caused by low intake of anti-inflammatory foods are associated with frailty incidence. For community-dwelling older adults, dietary interventions that lower E-DII scores (e.g., encouraging dietary fiber intake) may help prevent frailty. Geriatr Gerontol Int 2024; 24: 189-195.
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Affiliation(s)
- Bo-Kyung Son
- Institute for Future Initiatives, The University of Tokyo, Tokyo, Japan
- Institute of Gerontology, The University of Tokyo, Tokyo, Japan
- Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Weida Lyu
- Institute of Gerontology, The University of Tokyo, Tokyo, Japan
- Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tomoki Tanaka
- Institute of Gerontology, The University of Tokyo, Tokyo, Japan
| | | | - Masahiro Akishita
- Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Katsuya Iijima
- Institute for Future Initiatives, The University of Tokyo, Tokyo, Japan
- Institute of Gerontology, The University of Tokyo, Tokyo, Japan
- Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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Togashi K, Suzuki S, Mitobe Y, Nakagawa-Saito Y, Sugai A, Takenouchi S, Sugimoto M, Kitanaka C, Okada M. CEP-1347 Dually Targets MDM4 and PKC to Activate p53 and Inhibit the Growth of Uveal Melanoma Cells. Cancers (Basel) 2023; 16:118. [PMID: 38201546 PMCID: PMC10778035 DOI: 10.3390/cancers16010118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/11/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024] Open
Abstract
Uveal melanoma (UM) is among the most common primary intraocular neoplasms in adults, with limited therapeutic options for advanced/metastatic disease. Since UM is characterized by infrequent p53 mutation coupled with the overexpression of MDM4, a major negative regulator of p53, we aimed to investigate in this study the effects on UM cells of CEP-1347, a novel MDM4 inhibitor with a known safety profile in humans. We also examined the impact of CEP-1347 on the protein kinase C (PKC) pathway, known to play a pivotal role in UM cell growth. High-grade UM cell lines were used to analyze the effects of genetic and pharmacological inhibition of MDM4 and PKC, respectively, as well as those of CEP-1347 treatment, on p53 expression and cell viability. The results showed that, at its clinically relevant concentrations, CEP-1347 reduced not only MDM4 expression but also PKC activity, activated the p53 pathway, and effectively inhibited the growth of UM cells. Importantly, whereas inhibition of either MDM4 expression or PKC activity alone failed to efficiently activate p53 and inhibit cell growth, inhibition of both resulted in effective activation of p53 and inhibition of cell growth. These data suggest that there exists a hitherto unrecognized interaction between MDM4 and PKC to inactivate the p53-dependent growth control in UM cells. CEP-1347, which dually targets MDM4 and PKC, could therefore be a promising therapeutic candidate in the treatment of UM.
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Affiliation(s)
- Keita Togashi
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Department of Ophthalmology and Visual Sciences, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Shuhei Suzuki
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Department of Clinical Oncology, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Yuta Mitobe
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Department of Neurosurgery, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Yurika Nakagawa-Saito
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Asuka Sugai
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Senri Takenouchi
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Masahiko Sugimoto
- Department of Ophthalmology and Visual Sciences, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Research Institute for Promotion of Medical Sciences, Faculty of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Chifumi Kitanaka
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Research Institute for Promotion of Medical Sciences, Faculty of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Masashi Okada
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
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Yoshikawa N, Yoshitomi N, Nakada K, Sawada N. Distribution and role of d-glutamate, a novel d-amino acid identified in animals, in the reproductive tissues of male kuruma prawn Marsupenaeus japonicus. J Biochem 2023; 175:95-100. [PMID: 37787512 DOI: 10.1093/jb/mvad072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 09/12/2023] [Accepted: 09/21/2023] [Indexed: 10/04/2023] Open
Abstract
Some aquatic invertebrates contain free d-alanine. We previously showed copious amounts of free d-glutamate, a novel d-amino acid, in the tissue of the male reproductive organs of Marsupenaeus japonicus. Herein, we clarified the distribution and potential role of d-glutamate and d-alanine in male reproductive tissues, namely the testis, vas deferens and seminal receptacle at different growth stages of M. japonicus. The percentage of d-glutamate to total glutamate was over 50% in these tissues. In particular, the content of d-glutamate was the most abundant in the vas deferens, the ratio of d-glutamate to total glutamate was approximately 80%. In contrast, d-alanine content was the lowest in the vas deferens among these tissues. d-Glutamate content was the highest when the prawn weighed 12 g, indicating that d-glutamate is actively synthesized in the younger stage. Our findings suggest that d-glutamate plays an important role in the reproductive functions of M. japonicus.
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Affiliation(s)
- Naoko Yoshikawa
- Department of Materials and Life Science, Faculty of Science and Technology, Shizuoka Institute of Science and Technology, Fukuroi, Shizuoka 437-8555, Japan
| | - Natsuki Yoshitomi
- Department of Materials and Life Science, Faculty of Science and Technology, Shizuoka Institute of Science and Technology, Fukuroi, Shizuoka 437-8555, Japan
| | - Kazuki Nakada
- Department of Materials and Life Science, Faculty of Science and Technology, Shizuoka Institute of Science and Technology, Fukuroi, Shizuoka 437-8555, Japan
| | - Naomi Sawada
- Department of Materials and Life Science, Faculty of Science and Technology, Shizuoka Institute of Science and Technology, Fukuroi, Shizuoka 437-8555, Japan
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5
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Kiuchi S, Hisatake S, Kabuki T, Dobashi S, Murakami Y, Ikeda T. Importance of anemia in heart failure over blood pressure variability. Clin Cardiol 2023; 46:1495-1503. [PMID: 37649390 PMCID: PMC10716338 DOI: 10.1002/clc.24141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 08/08/2023] [Accepted: 08/21/2023] [Indexed: 09/01/2023] Open
Abstract
BACKGROUND The evaluation of arteriosclerosis (vascular function) is important when treating heart failure (HF). Vascular dysfunction is associated with anemia through renal function and endothelial nitric oxide synthase. Additionally, blood pressure (BP) variability (BPV) caused by vascular dysfunction is also associated with HF prognosis. However, how anemia and BPV may affect HF prognosis is unclear. METHODS Between January 2012 and July 2018, 214 patients with HF were hospitalized. The cardio-ankle vascular index (CAVI) as an index of arteriosclerosis of these patients was measured. The patients were divided into the elevated and preserved CAVI groups. We investigated the factors related to major adverse cardiovascular events (MACEs) as cardiovascular death or rehospitalization within 1 year after discharge. RESULTS In the elevated CAVI group, significant differences in body mass index (BMI), BPV, left ventricular dimension, and hemoglobin levels were observed between patients with and without MACEs. In the preserved CAVI group, significant differences in BMI, diastolic/mean BP, and hemoglobin levels were observed between those with and without MACEs. The multivariate analysis showed an independent association between hemoglobin levels and MACE occurrence in both the elevated and preserved CAVI groups (elevated CAVI group: hazard ratio [HR] = 0.800, p = .045 [model 1], HR = 0.802, p = .035 [model 2]; preserved CAVI group: HR = 0.783, p = .049 [model 1], HR = 0.752, p = .023 [model 2], and HR = 0.754, p = .024 [model 3]). CONCLUSIONS Anemia was independently associated with HF prognosis with or without arteriosclerosis.
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Affiliation(s)
- Shunsuke Kiuchi
- Department of Cardiovascular MedicineToho University Faculty of MedicineTokyoJapan
| | - Shinji Hisatake
- Department of Cardiovascular MedicineToho University Faculty of MedicineTokyoJapan
| | - Takayuki Kabuki
- Department of Cardiovascular MedicineToho University Faculty of MedicineTokyoJapan
| | - Shintaro Dobashi
- Department of Cardiovascular MedicineToho University Faculty of MedicineTokyoJapan
| | - Yoshiki Murakami
- Department of Cardiovascular MedicineToho University Faculty of MedicineTokyoJapan
| | - Takanori Ikeda
- Department of Cardiovascular MedicineToho University Faculty of MedicineTokyoJapan
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6
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Gerber R, de Necker L, van Vuren JHJ, Ikenaka Y, Nakayama SMM, Ishizuka M, Wepener V, Smit NJ. A stable isotope analysis of the dietary patterns of the aquatic apex predator, the African tigerfish (Hydrocynus vittatus). J Fish Biol 2023; 103:1129-1143. [PMID: 37498144 DOI: 10.1111/jfb.15516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 07/19/2023] [Accepted: 07/26/2023] [Indexed: 07/28/2023]
Abstract
Stable isotope analyses, specifically δ13 C and δ15 N, are useful tools increasingly used to understand ecosystem function, food web structures, and consumer diets. Although the iconic tigerfish Hydrocynus vittatus is regarded as an apex predator in southern African freshwater systems, little information is available regarding their feeding behavior and how this may change with growth or differ between ecosystems, with most information stemming from stomach content analyses (SCA). The aim of the present study was to address this lack of information through a baseline study of the diet of large and small tigerfish in various lentic and lotic ecosystems in South Africa using stable isotope methods. Fish and various food web components and food sources were collected from two river and two lake ecosystems in South Africa. The δ13 C and δ15 N values for all samples were determined and multivariate analyses and Bayesian analytical techniques applied to determine the feeding ecology of H. vittatus and how this may differ with size and habitat type. Analyses revealed a substantial difference in the type and abundance of food sources contributing to the diet of H. vittatus between ecosystems, most prominently between the lotic systems, where less dietary specialization was observed, and lentic systems where more specialization was observed. Furthermore, there was a distinct difference in diet between small and large tigerfish, especially in the lotic system, indicating an ontogenetic diet shift as tigerfish grow and further supporting previous SCA studies. This is the first study of its kind on the African continent for H. vittatus and the findings illustrate the value of stable isotope analysis in providing in-depth information into the feeding ecology of consumers and how this may differ between size classes and habitat types.
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Grants
- 127549 Department of Science and Innovation Professional Development Programme
- 22KK0163 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 17KK0009 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 18KK028708 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 17K2003807 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 18H0413208 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 20K20633 Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan
- 105979 National Research Foundation of South Africa
- 85505 National Research Foundation of South Africa
- 105122 National Research Foundation of South Africa
- K5-1922 Water Research Commission of South Africa
- K5-2185 Water Research Commission of South Africa
- JPMJSA1501 JST/JICA SATREPS (Science and Technology Research Partnership for Sustainable Development
- JPMJAS2001 aXis (Accelerating Social Implementation for SDGs Achievement
- PJ36210002 JST AJ-CORE
- JSPS CORE to CORE program
- Hokkaido University SOUSEI Tokutei Research
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Affiliation(s)
- Ruan Gerber
- Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Lizaan de Necker
- Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
- South African Institute for Aquatic Biodiversity (NRF-SAIAB), Makhanda, South Africa
| | - Johan H J van Vuren
- Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Yoshinori Ikenaka
- Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
- Translational Research Unit, Veterinary Teaching hospital, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
- One Health Research Center, Hokkaido University, Sapporo, Japan
| | - Shouta M M Nakayama
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Mayumi Ishizuka
- Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Victor Wepener
- Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Nico J Smit
- Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
- South African Institute for Aquatic Biodiversity (NRF-SAIAB), Makhanda, South Africa
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7
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Mitobe Y, Suzuki S, Nakagawa-Saito Y, Togashi K, Sugai A, Sonoda Y, Kitanaka C, Okada M. Antagonizing MDM2 Overexpression Induced by MDM4 Inhibitor CEP-1347 Effectively Reactivates Wild-Type p53 in Malignant Brain Tumor Cells. Cancers (Basel) 2023; 15:4326. [PMID: 37686602 PMCID: PMC10486490 DOI: 10.3390/cancers15174326] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 08/14/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023] Open
Abstract
The development of MDM4 inhibitors as an approach to reactivating p53 in human cancer is attracting increasing attention; however, whether they affect the function of MDM2 and how they interact with MDM2 inhibitors remain unknown. We addressed this question in the present study using CEP-1347, an inhibitor of MDM4 protein expression. The effects of CEP-1347, the genetic and/or pharmacological inhibition of MDM2, and their combination on the p53 pathway in malignant brain tumor cell lines expressing wild-type p53 were investigated by RT-PCR and Western blot analyses. The growth inhibitory effects of CEP-1347 alone or in combination with MDM2 on inhibition were examined by dye exclusion and/or colony formation assays. The treatment of malignant brain tumor cell lines with CEP-1347 markedly increased MDM2 protein expression, while blocking CEP-1347-induced MDM2 overexpression by genetic knockdown augmented the effects of CEP-1347 on the p53 pathway and cell growth. Blocking the MDM2-p53 interaction using the small molecule MDM2 inhibitor RG7112, but not MDM2 knockdown, reduced MDM4 expression. Consequently, RG7112 effectively cooperated with CEP-1347 to reduce MDM4 expression, activate the p53 pathway, and inhibit cell growth. The present results suggest the combination of CEP-1347-induced MDM2 overexpression with the selective inhibition of MDM2's interaction with p53, while preserving its ability to inhibit MDM4 expression, as a novel and rational strategy to effectively reactivate p53 in wild-type p53 cancer cells.
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Affiliation(s)
- Yuta Mitobe
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Department of Neurosurgery, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Shuhei Suzuki
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Department of Clinical Oncology, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Yurika Nakagawa-Saito
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Keita Togashi
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Department of Ophthalmology and Visual Sciences, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Asuka Sugai
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Yukihiko Sonoda
- Department of Neurosurgery, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Chifumi Kitanaka
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Research Institute for Promotion of Medical Sciences, Faculty of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Masashi Okada
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
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8
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Chan MP, Takenaka N, Satoh T. Impaired Insulin Signaling Mediated by the Small GTPase Rac1 in Skeletal Muscle of the Leptin-Deficient Obese Mouse. Int J Mol Sci 2023; 24:11531. [PMID: 37511290 PMCID: PMC10380855 DOI: 10.3390/ijms241411531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/05/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023] Open
Abstract
Insulin-stimulated glucose uptake in skeletal muscle is mediated by the glucose transporter GLUT4. The small GTPase Rac1 acts as a switch of signal transduction that regulates GLUT4 translocation to the plasma membrane following insulin stimulation. However, it remains obscure whether signaling cascades upstream and downstream of Rac1 in skeletal muscle are impaired by obesity that causes insulin resistance and type 2 diabetes. In an attempt to clarify this point, we investigated Rac1 signaling in the leptin-deficient (Lepob/ob) mouse model. Here, we show that insulin-stimulated GLUT4 translocation and Rac1 activation are almost completely abolished in Lepob/ob mouse skeletal muscle. Phosphorylation of the protein kinase Akt2 and plasma membrane translocation of the guanine nucleotide exchange factor FLJ00068 following insulin stimulation were also diminished in Lepob/ob mice. On the other hand, the activation of another small GTPase RalA, which acts downstream of Rac1, by the constitutively activated form of Akt2, FLJ00068, or Rac1, was partially abrogated in Lepob/ob mice. Taken together, we conclude that insulin-stimulated glucose uptake is impaired by two mechanisms in Lepob/ob mouse skeletal muscle: one is the complete inhibition of Akt2-mediated activation of Rac1, and the other is the partial inhibition of RalA activation downstream of Rac1.
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Affiliation(s)
| | | | - Takaya Satoh
- Laboratory of Cell Biology, Department of Biological Chemistry, Graduate School of Science, Osaka Metropolitan University, Sakai 599-8531, Japan; (M.P.C.); (N.T.)
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9
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Mitobe Y, Suzuki S, Nakagawa-Saito Y, Togashi K, Sugai A, Sonoda Y, Kitanaka C, Okada M. The Novel MDM4 Inhibitor CEP-1347 Activates the p53 Pathway and Blocks Malignant Meningioma Growth In Vitro and In Vivo. Biomedicines 2023; 11:1967. [PMID: 37509605 PMCID: PMC10377688 DOI: 10.3390/biomedicines11071967] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/21/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
A significant proportion of meningiomas are clinically aggressive, but there is currently no effective chemotherapy for meningiomas. An increasing number of studies have been conducted to develop targeted therapies, yet none have focused on the p53 pathway as a potential target. In this study, we aimed to determine the in vitro and in vivo effects of CEP-1347, a small-molecule inhibitor of MDM4 with known safety in humans. The effects of CEP-1347 and MDM4 knockdown on the p53 pathway in human meningioma cell lines with and without p53 mutation were examined by RT-PCR and Western blot analyses. The growth inhibitory effects of CEP-1347 were examined in vitro and in a mouse xenograft model of meningioma. In vitro, CEP-1347 at clinically relevant concentrations inhibited MDM4 expression, activated the p53 pathway in malignant meningioma cells with wild-type p53, and exhibited preferential growth inhibitory effects on cells expressing wild-type p53, which was mostly mimicked by MDM4 knockdown. CEP-1347 effectively inhibited the growth of malignant meningioma xenografts at a dose that was far lower than the maximum dose that could be safely given to humans. Our findings suggest targeting the p53 pathway with CEP-1347 represents a novel and viable approach to treating aggressive meningiomas.
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Affiliation(s)
- Yuta Mitobe
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Department of Neurosurgery, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Shuhei Suzuki
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Department of Clinical Oncology, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Yurika Nakagawa-Saito
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Keita Togashi
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Department of Ophthalmology and Visual Sciences, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Asuka Sugai
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Yukihiko Sonoda
- Department of Neurosurgery, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Chifumi Kitanaka
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
- Research Institute for Promotion of Medical Sciences, Faculty of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
| | - Masashi Okada
- Department of Molecular Cancer Science, School of Medicine, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585, Japan
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10
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Mi-ichi F, Ishikawa T, Tam VK, Deloer S, Hamano S, Hamada T, Yoshida H. Characterization of Entamoeba histolytica adenosine 5'-phosphosulfate (APS) kinase; validation as a target and provision of leads for the development of new drugs against amoebiasis. PLoS Negl Trop Dis 2019; 13:e0007633. [PMID: 31425516 PMCID: PMC6715247 DOI: 10.1371/journal.pntd.0007633] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 08/29/2019] [Accepted: 07/15/2019] [Indexed: 12/18/2022] Open
Abstract
Background Amoebiasis, caused by Entamoeba histolytica infection, is a global public health problem. However, available drugs to treat amoebiasis are currently limited, and no effective vaccine exists. Therefore, development of new preventive measures against amoebiasis is urgently needed. Methodology/Principal findings Here, to develop new drugs against amoebiasis, we focused on E. histolytica adenosine 5′-phosphosulfate kinase (EhAPSK), an essential enzyme in Entamoeba sulfolipid metabolism. Fatty alcohol disulfates and cholesteryl sulfate, sulfolipids synthesized in Entamoeba, play important roles in trophozoite proliferation and cyst formation. These processes are closely associated with clinical manifestation and severe pathogenesis of amoebiasis and with disease transmission, respectively. We validated a combination approach of in silico molecular docking analysis and an in vitro enzyme activity assay for large scale screening. Docking simulation ranked the binding free energy between a homology modeling structure of EhAPSK and 400 compounds. The 400 compounds were also screened by a 96-well plate-based in vitro APSK activity assay. Among fifteen compounds identified as EhAPSK inhibitors by the in vitro system, six were ranked by the in silico analysis as having high affinity toward EhAPSK. Furthermore, 2-(3-fluorophenoxy)-N-[4-(2-pyridyl)thiazol-2-yl]-acetamide, 3-phenyl-N-[4-(2-pyridyl)thiazol-2-yl]-imidazole-4-carboxamide, and auranofin, which were identified as EhAPSK inhibitors by both in silico and in vitro analyses, halted not only Entamoeba trophozoite proliferation but also cyst formation. These three compounds also dose-dependently impaired the synthesis of sulfolipids in E. histolytica. Conclusions/Significance Hence, the combined approach of in silico and in vitro-based EhAPSK analyses identified compounds that can be evaluated for their effects on Entamoeba. This can provide leads for the development of new anti-amoebic and amoebiasis transmission-blocking drugs. This strategy can also be applied to identify specific APSK inhibitors, which will benefit research into sulfur metabolism and the ubiquitous pathway terminally synthesizing essential sulfur-containing biomolecules. Amoebiasis is a parasitic disease caused by Entamoeba histolytica that is an important health problem worldwide because of high morbidity and mortality rates. However, clinical options are inadequate; therefore, developing new preventive measures, such as anti-amoebic drugs, is urgently needed. In general, for the development of new drugs, the identification of appropriate leads and targets is a prerequisite. Here, to develop new drugs against amoebiasis, we focused on E. histolytica adenosine 5′-phosphosulfate kinase (EhAPSK), an essential enzyme in sulfur metabolism. An EhAPSK-based combination approach of computer-based in silico and laboratory-based in vitro analyses enabled us to screen 400 chemicals, from which we identified 15 that inhibit EhAPSK activity. Furthermore, among them, three compounds halted biological processes in Entamoeba that are closely associated with the clinical manifestation and pathogenesis of amoebiasis and with disease transmission. Hence, this study provides leads as well as a target for the development of new drugs against amoebiasis. This study also provides a basis to identify inhibitors for use in the study of sulfur metabolism, an important topic in general biochemistry and physiology.
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Affiliation(s)
- Fumika Mi-ichi
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Nabeshima, Saga, Japan
- * E-mail:
| | - Takeshi Ishikawa
- Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Sakamoto, Nagasaki, Japan
| | - Vo Kha Tam
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Nabeshima, Saga, Japan
| | - Sharmina Deloer
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Nabeshima, Saga, Japan
| | - Shinjiro Hamano
- Department of Parasitology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Sakamoto, Nagasaki, Japan
| | - Tsuyoshi Hamada
- Nagasaki Advanced Computing Center, Nagasaki University, Bunkyo-machi, Nagasaki, Japan
| | - Hiroki Yoshida
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Nabeshima, Saga, Japan
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11
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Abstract
The with no lysine (WNK) protein kinase family is conserved among many species. Some mutations in human WNK gene are associated with pseudohypoaldosteronism type II, a form of hypertension, and hereditary sensory and autonomic neuropathy type 2A. In kidney, WNK regulates the activity of STE20/SPS1-related, proline alanine-rich kinase and/or oxidative-stress responsive 1, which in turn regulate ion co-transporters. The misregulation of this pathway is involved in the pathogenesis of pseudohypoaldosteronism type II. In the neural system, WNK is involved in the specification of the cholinergic neuron, but the pathogenesis of hereditary sensory and autonomic neuropathy type 2A is still unknown. To better understand the WNK pathway, we isolated WNK-associated genes using Drosophila. We identified Glycogen synthase kinase 3ß (GSK3ß)/Shaggy (Sgg) as a candidate gene that was shown to interact with the WNK signaling pathway in both Drosophila and mammalian cells. Furthermore, GSK3ß was involved in neural specification downstream of WNK. These results suggest that GSK3ß/Sgg functions as a positive effector in the WNK signaling pathway.
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Affiliation(s)
- Atsushi Sato
- Department of Molecular Cell Biology and Joint Usage/Research Center for Intractable Diseases, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Bunkyo-ku, Tokyo, Japan
| | - Hiroshi Shibuya
- Department of Molecular Cell Biology and Joint Usage/Research Center for Intractable Diseases, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Bunkyo-ku, Tokyo, Japan
- * E-mail:
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12
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Takeishi R, Magara J, Watanabe M, Tsujimura T, Hayashi H, Hori K, Inoue M. Effects of pharyngeal electrical stimulation on swallowing performance. PLoS One 2018; 13:e0190608. [PMID: 29293640 PMCID: PMC5749827 DOI: 10.1371/journal.pone.0190608] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 12/18/2017] [Indexed: 11/19/2022] Open
Abstract
Pharyngeal electrical stimulation (PEStim) has been found to facilitate voluntary swallowing. This study investigated how PEStim contributed to modulation of swallowing function in 15 healthy humans. In the involuntary swallowing test, water was injected onto the pharynx at 0.05 ml/s and the onset latency of the first swallow was measured. In the voluntary swallowing test, subjects swallowed their own saliva as quickly as possible for 30 s and the number of swallows was counted. Voluntary and involuntary swallowing was evaluated before (baseline), immediately after, and every 10 min after 10-min PEStim for 60 min. A voluntary swallowing test with simultaneous 30-s PEStim was also conducted before and 60 min after 10-min PEStim. The number of voluntary swallows with simultaneous PEStim significantly increased over 60 min after 10-min PEStim compared with the baseline. The onset latency of the first swallow in the involuntary swallowing test was not affected by 10-min PEStim. The results suggest that PEStim may have a long-term facilitatory effect on the initiation of voluntary swallowing in healthy humans, but not on peripherally-evoked swallowing. The physiological implications of this modulation are discussed.
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Affiliation(s)
- Ryosuke Takeishi
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, 2–5274 Gakkocho-dori, Chuo-ku, Niigata, Japan
| | - Jin Magara
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, 2–5274 Gakkocho-dori, Chuo-ku, Niigata, Japan
| | - Masahiro Watanabe
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, 2–5274 Gakkocho-dori, Chuo-ku, Niigata, Japan
| | - Takanori Tsujimura
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, 2–5274 Gakkocho-dori, Chuo-ku, Niigata, Japan
| | - Hirokazu Hayashi
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, 2–5274 Gakkocho-dori, Chuo-ku, Niigata, Japan
| | - Kazuhiro Hori
- Division of Comprehensive Prosthodontics, Niigata University Graduate School of Medical and Dental Sciences, 2–5274 Gakkocho-dori, Chuo-ku, Niigata, Japan
| | - Makoto Inoue
- Division of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences, 2–5274 Gakkocho-dori, Chuo-ku, Niigata, Japan
- * E-mail:
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13
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Fukuda T, Bouchi R, Terashima M, Sasahara Y, Asakawa M, Takeuchi T, Nakano Y, Murakami M, Minami I, Izumiyama H, Hashimoto K, Yoshimoto T, Ogawa Y. Ipragliflozin Reduces Epicardial Fat Accumulation in Non-Obese Type 2 Diabetic Patients with Visceral Obesity: A Pilot Study. Diabetes Ther 2017; 8:851-861. [PMID: 28616806 PMCID: PMC5544615 DOI: 10.1007/s13300-017-0279-y] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Indexed: 12/25/2022] Open
Abstract
INTRODUCTION Epicardial fat (EF) was reported to be independently associated with cardiovascular disease regardless of obesity. We have previously reported that a sodium-glucose co-transporter-2 (SGLT2) inhibitor, luseogliflozin, reduces the EF volume (EFV) in parallel with the reduction of body weight in obese patients (BMI ≥25 kg/m2) with type 2 diabetes. However, it is unknown whether SGLT2 inhibitors could reduce EFV in non-obese patients (BMI <25 kg/m2) with type 2 diabetes. Therefore, we evaluated the effect of SGLT2 inhibitors on the EFV in non-obese type 2 diabetic patients with visceral obesity in this pilot study. METHODS Nine of type 2 diabetic patients (mean age 66 ± 8 years; 33% female) with HbA1c 6.5-9.0%, body mass index (BMI, kg/m2) <25.0, and visceral fat area (VFA, cm2) ≥100 were enrolled. Participants were administered ipragliflozin 50 mg daily. EFV [median (interquartile range), cm3] was measured by magnetic resonance imaging. Primary endpoint was the change in EFV at 12 weeks. VFA and liver attenuation index (LAI), skeletal muscle index (SMI), and body fat (%) were also assessed at baseline and at 12 weeks. RESULTS The EFV was significantly reduced from 102 (79-126) cm3 to 89 (66-109) cm3 by ipraglifrozin (p = 0.008). The body weight, BMI, HbA1c, fasting plasma glucose, insulin, homeostasis model assessment-insulin resistance, triglycerides, leptin, body fat, android, gynoid, and VFA were significantly reduced and high-density lipoprotein cholesterol was significantly increased by ipraglifrozin at 12 weeks, whereas SFA and LAI were unchanged. The change in EFV was significantly correlated with the change in BMI. CONCLUSIONS A12-week intervention of ipragliflozin reduced the EFV in non-obese type 2 diabetic patients with visceral adiposity. CLINICAL TRIAL REGISTRATION UMIN Clinical Trial Registry: UMIN000019071. FUNDING Astellas Pharma Inc. and the Grants-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan.
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Affiliation(s)
- Tatsuya Fukuda
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ryotaro Bouchi
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
| | | | - Yuriko Sasahara
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masahiro Asakawa
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takato Takeuchi
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yujiro Nakano
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masanori Murakami
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Isao Minami
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hajime Izumiyama
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- Center for Medical Welfare and Liaison Services, Tokyo Medical and Dental University, Tokyo, Japan
| | - Koshi Hashimoto
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- Department of Preemptive Medicine and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takanobu Yoshimoto
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoshihiro Ogawa
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- CREST, Japan Agency for Medical Research and Development, Tokyo, Japan
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Hirata E, Ohya Y, Suzuki K. Atg4 plays an important role in efficient expansion of autophagic isolation membranes by cleaving lipidated Atg8 in Saccharomyces cerevisiae. PLoS One 2017; 12:e0181047. [PMID: 28704456 PMCID: PMC5509253 DOI: 10.1371/journal.pone.0181047] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 06/26/2017] [Indexed: 12/11/2022] Open
Abstract
Autophagy, an intracellular degradation system, is highly conserved among eukaryotes from yeast to mammalian cells. In the yeast Saccharomyces cerevisiae, most Atg (autophagy-related) proteins, which are essential for autophagosome formation, are recruited to a restricted region close to the vacuole, termed the vacuole-isolation membrane contact site (VICS), upon induction of autophagy. Subsequently, the isolation membrane (IM) expands and sequesters cytoplasmic materials to become a closed autophagosome. In S. cerevisiae, the ubiquitin-like protein Atg8 is C-terminally conjugated to the phospholipid phosphatidylethanolamine (PE) to generate Atg8-PE. During autophagosome formation, Atg8-PE is cleaved by Atg4 to release delipidated Atg8 (Atg8G116) and PE. Although delipidation of Atg8-PE is important for autophagosome formation, it remains controversial whether the delipidation reaction is required for targeting of Atg8 to the VICS or for subsequent IM expansion. We used an IM visualization technique to clearly demonstrate that delipidation of Atg8-PE is dispensable for targeting of Atg8 to the VICS, but required for IM expansion. Moreover, by overexpressing Atg8G116, we showed that the delipidation reaction of Atg8-PE by Atg4 plays an important role in efficient expansion of the IM other than supplying unlipidated Atg8G116. Finally, we suggested the existence of biological membranes at the Atg8-labeled structures in Atg8-PE delipidation-defective cells, but not at those in atg2Δ cells. Taken together, it is likely that Atg2 is involved in localization of biological membranes to the VICS, where Atg4 is responsible for IM expansion.
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Affiliation(s)
- Eri Hirata
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
| | - Yoshikazu Ohya
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
| | - Kuninori Suzuki
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
- Bioimaging Center, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba, Japan
- * E-mail:
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15
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Bouchi R, Fukuda T, Takeuchi T, Nakano Y, Murakami M, Minami I, Izumiyama H, Hashimoto K, Yoshimoto T, Ogawa Y. Insulin Treatment Attenuates Decline of Muscle Mass in Japanese Patients with Type 2 Diabetes. Calcif Tissue Int 2017; 101:1-8. [PMID: 28246927 PMCID: PMC5486921 DOI: 10.1007/s00223-017-0251-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 02/01/2017] [Indexed: 12/20/2022]
Abstract
Sarcopenia is defined as an age-related loss of skeletal muscle mass and strength, and is a major cause of disability and mobility limitations. Recent studies have demonstrated that type 2 diabetes and insulin signaling deficiencies contribute to the progression of sarcopenia, suggesting that a sufficient supply of insulin to the skeletal muscles may be important for the maintenance of muscle function; however, little has been reported regarding whether insulin treatment can protect against sarcopenia. We conducted a retrospective observational study to examine the impact of insulin treatment on the muscle mass of patients with type 2 diabetes. A total of 312 patients (mean age: 64 ± 11 years; 40.8% female; 27.6% treated with insulin) were studied in this retrospective observational study. Skeletal muscle index (SMI) and grip strength (kg) were used to assess sarcopenia. The prevalence of sarcopenia was 18.0%. Insulin treatment was shown to be protective against the annual decline of SMI (standardized β 0.195; p = 0.025) even after adjusting for covariates, including age, gender, duration of diabetes, and body mass index. In a cohort matched by propensity scores, insulin treatment significantly increased the 1-year change in SMI (mean ± SE) compared with non-insulin-treated group (2.40 ± 0.98% vs. -0.43 ± 0.98%; p = 0.050). Our data suggest that insulin treatment could attenuate the progression of sarcopenia in patients with type 2 diabetes.
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Affiliation(s)
- Ryotaro Bouchi
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
| | - Tatsuya Fukuda
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
| | - Takato Takeuchi
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
| | - Yujiro Nakano
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
| | - Masanori Murakami
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
| | - Isao Minami
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
| | - Hajime Izumiyama
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
- 0000 0001 1014 9130grid.265073.5Center for Medical Welfare and Liaison Services, Tokyo Medical and Dental University, Tokyo, Japan
| | - Koshi Hashimoto
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
- 0000 0001 1014 9130grid.265073.5Department of Preemptive Medicine and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takanobu Yoshimoto
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
| | - Yoshihiro Ogawa
- 0000 0001 1014 9130grid.265073.5Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519 Japan
- 0000 0004 1754 9200grid.419082.6CREST, Japan Agency for Medical Research and Development, Tokyo, Japan
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Sato K, Nishijima T, Yokokawa T, Fujita S. Acute bout of exercise induced prolonged muscle glucose transporter-4 translocation and delayed counter-regulatory hormone response in type 1 diabetes. PLoS One 2017; 12:e0178505. [PMID: 28570686 PMCID: PMC5453522 DOI: 10.1371/journal.pone.0178505] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 05/15/2017] [Indexed: 11/18/2022] Open
Abstract
Previous studies have demonstrated that an acute bout of aerobic exercise induces a subsequent delayed onset of hypoglycemia among patients with type 1 diabetes. However, the mechanisms of exercise-induced hypoglycemia in type 1 diabetes are still unclear. Streptozotocin (STZ) was injected to 6-week-old male Wistar rats, and three days after STZ injection, animals were randomly assigned into 2 groups: STZ with insulin only (STZ) and STZ with insulin and exercise (STZ+EX). Normal Wistar rats with exercise were used as control (CON+EX). Insulin was intraperitoneally injected (0.5 U/kg) to both STZ groups (-0.5 h), and a bout of aerobic exercise (15 m/min for 30 min) was conducted at euglycemic conditions (0 h). Blood was collected at 0, 1, 3, and 5 h after exercise from the carotid artery. While the blood glucose level was stable during the post-exercise period (0-5 h) in the STZ and CON+EX groups, it decreased significantly only in the STZ+EX group at 3 h. Plasma glucagon, adrenalin, and noradrenalin levels significantly increased at 1 h in the STZ group, whereas significant hormonal responses were observed at 5 h in the STZ+EX group. In skeletal muscle glucose metabolism-related pathway, the level of glucose transporter-4 (GLUT-4) translocation was significantly higher at 1 h in the CON and STZ groups. However, in the STZ+EX group, these activations were maintained by 5 h, indicating a sustained glucose metabolism in the STZ+EX group. A single bout of aerobic exercise induced a delayed onset of hypoglycemia in STZ-treated rats. A prolonged enhancement of GLUT-4 translocation and delayed counter-regulatory hormone responses may have contributed to the induction of hypoglycemia.
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Affiliation(s)
- Koji Sato
- Faculty of Sport and Health Science, Ritsumeikan University, Shiga, Japan
- Graduate School of Human Development and Environment, Kobe University, Kobe, Japan
- * E-mail:
| | - Takeshi Nishijima
- Department of Health Promotion Sciences, Tokyo Metropolitan University, Tokyo, Japan
| | - Takumi Yokokawa
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan
| | - Satoshi Fujita
- Faculty of Sport and Health Science, Ritsumeikan University, Shiga, Japan
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Fukuda T, Bouchi R, Takeuchi T, Nakano Y, Murakami M, Minami I, Izumiyama H, Hashimoto K, Yoshimoto T, Ogawa Y. Association of diabetic retinopathy with both sarcopenia and muscle quality in patients with type 2 diabetes: a cross-sectional study. BMJ Open Diabetes Res Care 2017; 5:e000404. [PMID: 28761661 PMCID: PMC5530250 DOI: 10.1136/bmjdrc-2017-000404] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 03/29/2017] [Accepted: 04/26/2017] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE To examine whether the existence and severity of diabetic retinopathy (DR) could be associated with the prevalent sarcopenia and muscle quality in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS This is a cross-sectional study of 316 patients with type 2 diabetes (mean age 65±12 years; 38% female). Body compositions were measured by the dual-energy X-ray absorptiometry. Patients were divided into three groups: patients without DR (NDR), with non-proliferative DR (NPDR) and proliferative DR (PDR). Sarcopenia was diagnosed according to the criteria for Asians, using both skeletal muscle index (SMI) and grip strength (kg). Muscle quality was also determined by the grip strength divided by SMI. Logistic regression analyses were carried out to assess the cross-sectional association of the severity of DR with sarcopenia. In addition, linear regression analyses were performed to determine the associations between DR and muscle quality. Selection of covariates in the multivariate logistic and linear regression analyses was done by a stepwise procedure. RESULTS Among the patients examined, NDR, NPDR and PDR were diagnosed in 261, 38 and 17 patients, respectively. The prevalence of sarcopenia significantly increased along with the progression of DR. Multivariate logistic regression analysis showed that PDR is significantly associated with sarcopenia (OR 7.78, 95% CI 1.52 to 39.81, p=0.014) and low muscle strength (OR 6.25, 95% CI 1.15 to 33.96, p=0.034). Multivariate linear regression analysis additionally showed that the existence of DR was significantly associated with the muscle quality (standardized β -0.136, p=0.005 for NPDR, standardized β -0.146, p=0.003 for PDR). CONCLUSIONS This study provides evidence that PDR is significantly associated with sarcopenia, and the existence of DR increases the risk for low muscle quality in patients with type 2 diabetes.
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Affiliation(s)
- Tatsuya Fukuda
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ryotaro Bouchi
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takato Takeuchi
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yujiro Nakano
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Masanori Murakami
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Isao Minami
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hajime Izumiyama
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- Center for Medical Welfare and Liaison Services, Tokyo Medical and Dental University, Tokyo, Japan
| | - Koshi Hashimoto
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- Department of Preemptive Medicine and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takanobu Yoshimoto
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoshihiro Ogawa
- Department of Molecular Endocrinology and Metabolism, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- CREST, Japan Agency for Medical Research and Development, Tokyo, Japan
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Takenaka N, Nihata Y, Satoh T. Rac1 Activation Caused by Membrane Translocation of a Guanine Nucleotide Exchange Factor in Akt2-Mediated Insulin Signaling in Mouse Skeletal Muscle. PLoS One 2016; 11:e0155292. [PMID: 27163697 PMCID: PMC4862641 DOI: 10.1371/journal.pone.0155292] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 04/27/2016] [Indexed: 11/25/2022] Open
Abstract
Insulin-stimulated glucose uptake in skeletal muscle is mediated by the glucose transporter GLUT4, which is translocated to the plasma membrane following insulin stimulation. Several lines of evidence suggested that the protein kinase Akt2 plays a key role in this insulin action. The small GTPase Rac1 has also been implicated as a regulator of insulin-stimulated GLUT4 translocation, acting downstream of Akt2. However, the mechanisms whereby Akt2 regulates Rac1 activity remain obscure. The guanine nucleotide exchange factor FLJ00068 has been identified as a direct regulator of Rac1 in Akt2-mediated signaling, but its characterization was performed mostly in cultured myoblasts. Here, we provide in vivo evidence that FLJ00068 indeed acts downstream of Akt2 as a Rac1 regulator by using mouse skeletal muscle. Small interfering RNA knockdown of FLJ00068 markedly diminished GLUT4 translocation to the sarcolemma following insulin administration or ectopic expression of a constitutively activated mutant of either phosphoinositide 3-kinase or Akt2. Additionally, insulin and these constitutively activated mutants caused the activation of Rac1 as shown by immunofluorescent microscopy using a polypeptide probe specific to activated Rac1 in isolated gastrocnemius muscle fibers and frozen sections of gastrocnemius muscle. This Rac1 activation was also abrogated by FLJ00068 knockdown. Furthermore, we observed translocation of FLJ00068 to the cell periphery following insulin stimulation in cultured myoblasts. Localization of FLJ00068 in the plasma membrane in insulin-stimulated, but not unstimulated, myoblasts and mouse gastrocnemius muscle was further affirmed by subcellular fractionation and subsequent immunoblotting. Collectively, these results strongly support a critical role of FLJ00068 in Akt2-mediated Rac1 activation in mouse skeletal muscle insulin signaling.
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Affiliation(s)
- Nobuyuki Takenaka
- Laboratory of Cell Biology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka, Japan
| | - Yuma Nihata
- Laboratory of Cell Biology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka, Japan
| | - Takaya Satoh
- Laboratory of Cell Biology, Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Sakai, Osaka, Japan
- * E-mail:
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