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  1. Book: Pancreatic beta cell in health and disease

    Seino, Susumu

    2008  

    Author's details Susumu Seino ... (ed.)
    Language English
    Size XV, 474 S. : Ill., graph. Darst.
    Publisher Springer Japan
    Publishing place Tokyo
    Publishing country Japan
    Document type Book
    HBZ-ID HT015465595
    ISBN 978-4-431-75451-0 ; 4-431-75451-2 ; 9784431754527 ; 4431754520
    Database Catalogue ZB MED Medicine, Health

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  2. Article: More β-cell researchers are wanted!

    Seino, Susumu

    Diabetology international

    2016  Volume 7, Issue 2, Page(s) 101–103

    Language English
    Publishing date 2016-04-08
    Publishing country Japan
    Document type Editorial
    ZDB-ID 2574501-3
    ISSN 2190-1686 ; 2190-1678
    ISSN (online) 2190-1686
    ISSN 2190-1678
    DOI 10.1007/s13340-016-0266-y
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Braving the Element: Pancreatic β-Cell Dysfunction and Adaptation in Response to Arsenic Exposure.

    Carmean, Christopher M / Seino, Susumu

    Frontiers in endocrinology

    2019  Volume 10, Page(s) 344

    Abstract: Type 2 diabetes mellitus (T2DM) is a serious global health problem, currently affecting an estimated 451 million people worldwide. T2DM is characterized by hyperglycemia and low insulin relative to the metabolic demand. The precise contributing factors ... ...

    Abstract Type 2 diabetes mellitus (T2DM) is a serious global health problem, currently affecting an estimated 451 million people worldwide. T2DM is characterized by hyperglycemia and low insulin relative to the metabolic demand. The precise contributing factors for a given individual vary, but generally include a combination of insulin resistance and insufficient insulin secretion. Ultimately, the progression to diabetes occurs only after β-cells fail to meet the needs of the individual. The stresses placed upon β-cells in this context manifest as increased oxidative damage, local inflammation, and ER stress, often inciting a destructive spiral of β-cell death, increased metabolic stress due to further insufficiency, and additional β-cell death. Several pathways controlling insulin resistance and β-cell adaptation/survival are affected by a class of exogenous bioactive compounds deemed endocrine disrupting chemicals (EDCs). Epidemiological studies have shown that, in several regions throughout the world, exposure to the EDC inorganic arsenic (iAs) correlates significantly with T2DM. It has been proposed that a lifetime of exposure to iAs may exacerbate problems with both insulin sensitivity as well as β-cell function/survival, promoting the development of T2DM. This review focuses on the mechanisms of iAs action as they relate to known adaptive and maladaptive pathways in pancreatic β-cells.
    Language English
    Publishing date 2019-06-14
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 2592084-4
    ISSN 1664-2392
    ISSN 1664-2392
    DOI 10.3389/fendo.2019.00344
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Dopamine Negatively Regulates Insulin Secretion Through Activation of D1-D2 Receptor Heteromer.

    Uefune, Fumiya / Aonishi, Toru / Kitaguchi, Tetsuya / Takahashi, Harumi / Seino, Susumu / Sakano, Daisuke / Kume, Shoen

    Diabetes

    2022  Volume 71, Issue 9, Page(s) 1946–1961

    Abstract: There is increasing evidence that dopamine (DA) functions as a negative regulator of glucose-stimulated insulin secretion; however, the underlying molecular mechanism remains unknown. Using total internal reflection fluorescence microscopy, we monitored ... ...

    Abstract There is increasing evidence that dopamine (DA) functions as a negative regulator of glucose-stimulated insulin secretion; however, the underlying molecular mechanism remains unknown. Using total internal reflection fluorescence microscopy, we monitored insulin granule exocytosis in primary islet cells to dissect the effect of DA. We found that D1 receptor antagonists rescued the DA-mediated inhibition of glucose-stimulated calcium (Ca2+) flux, thereby suggesting a role of D1 in the DA-mediated inhibition of insulin secretion. Overexpression of D2, but not D1, alone exerted an inhibitory and toxic effect that abolished the glucose-stimulated Ca2+ influx and insulin secretion in β-cells. Proximity ligation and Western blot assays revealed that D1 and D2 form heteromers in β-cells. Treatment with a D1-D2 heteromer agonist, SKF83959, transiently inhibited glucose-induced Ca2+ influx and insulin granule exocytosis. Coexpression of D1 and D2 enabled β-cells to bypass the toxic effect of D2 overexpression. DA transiently inhibited glucose-stimulated Ca2+ flux and insulin exocytosis by activating the D1-D2 heteromer. We conclude that D1 protects β-cells from the harmful effects of DA by modulating D2 signaling. The finding will contribute to our understanding of the DA signaling in regulating insulin secretion and improve methods for preventing and treating diabetes.
    MeSH term(s) Calcium/metabolism ; Dopamine/pharmacology ; Glucose/pharmacology ; Insulin Secretion ; Insulins ; Receptors, Dopamine D1/metabolism ; Receptors, Dopamine D2/genetics ; Receptors, Dopamine D2/metabolism
    Chemical Substances Insulins ; Receptors, Dopamine D1 ; Receptors, Dopamine D2 ; Glucose (IY9XDZ35W2) ; Calcium (SY7Q814VUP) ; Dopamine (VTD58H1Z2X)
    Language English
    Publishing date 2022-06-18
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 80085-5
    ISSN 1939-327X ; 0012-1797
    ISSN (online) 1939-327X
    ISSN 0012-1797
    DOI 10.2337/db21-0644
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: O-GlcNAcylation of myocyte-specific enhancer factor 2D negatively regulates insulin secretion from pancreatic β-cells.

    Yoshida, Mai / Yokoi, Norihide / Takahashi, Harumi / Hatano, Naoya / Hayami, Tomohide / Ogawa, Wataru / Seino, Susumu

    Biochemical and biophysical research communications

    2022  Volume 605, Page(s) 90–96

    Abstract: Patients with type 2 diabetes often exhibit impairments in both glucose-induced insulin secretion (GIIS) and incretin-induced insulin secretion (IIIS). These phenotypes are associated with altered glucose metabolism in pancreatic β-cells, although the ... ...

    Abstract Patients with type 2 diabetes often exhibit impairments in both glucose-induced insulin secretion (GIIS) and incretin-induced insulin secretion (IIIS). These phenotypes are associated with altered glucose metabolism in pancreatic β-cells, although the molecular mechanisms remain unclear. Here, we used MIN6-K8 pancreatic β-cell lines as a model to examine the effect of O-linked N-acetylglucosamine glycosylation (O-GlcNAcylation), a glucose-induced protein posttranslational modification, on insulin secretion. O-GlcNAcylation was enhanced in high-glucose-treated MIN6-K8 cells, and high levels of O-GlcNAcylation attenuated PKA-dependent phosphorylation, suggesting that the two protein modifications may compete with each other. Immunoprecipitation proteomic analysis identified six candidate proteins that were O-GlcNAcylated by high-glucose treatment, whereas the O-GlcNAcylations were removed by treatment with an incretin mimetic, exendin-4. Among these proteins, knockdown of myocyte enhancer factor 2D (Mef2d) enhanced insulin secretion, and high-glucose treatment increased the level of O-GlcNAcylation of Mef2d in MIN6-K8 cells. Furthermore, knockout of Mef2d promoted GIIS in MIN6-K8 cells, whereas adenovirus-mediated rescue of Mef2d decreased GIIS in the knockout cells. These results suggest that Mef2d negatively regulates insulin secretion through O-GlcNAcylation.
    MeSH term(s) Acetylglucosamine/metabolism ; Diabetes Mellitus, Type 2/metabolism ; Glucose/metabolism ; Humans ; Incretins ; Insulin Secretion ; MEF2 Transcription Factors/metabolism ; Protein Processing, Post-Translational ; Proteomics
    Chemical Substances Incretins ; MEF2 Transcription Factors ; Glucose (IY9XDZ35W2) ; Acetylglucosamine (V956696549)
    Language English
    Publishing date 2022-03-08
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 205723-2
    ISSN 1090-2104 ; 0006-291X ; 0006-291X
    ISSN (online) 1090-2104 ; 0006-291X
    ISSN 0006-291X
    DOI 10.1016/j.bbrc.2022.03.036
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Effect of Roxadustat on Thyroid Function in Patients With Renal Anemia.

    Haraguchi, Takuya / Hamamoto, Yoshiyuki / Kuwata, Hitoshi / Yamazaki, Yuji / Nakatani, Susumu / Hyo, Takanori / Yamada, Yuichiro / Yabe, Daisuke / Seino, Yutaka

    The Journal of clinical endocrinology and metabolism

    2023  Volume 109, Issue 1, Page(s) e69–e75

    Abstract: Context: Roxadustat, a hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor, a recently developed class of drugs for treatment of anemia in chronic kidney disease (CKD), is reported to have a structure unlike that of other HIF-PH inhibitors ... ...

    Abstract Context: Roxadustat, a hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor, a recently developed class of drugs for treatment of anemia in chronic kidney disease (CKD), is reported to have a structure unlike that of other HIF-PH inhibitors but similar to that of triiodothyronine and bind to the thyroid hormone receptor in vitro. However, reports on the effects of roxadustat on thyroid function are limited and not detailed, and it remains unknown whether other HIF-PH inhibitors also affect thyroid function.
    Objective: To compare the effect of roxadustat with daprodustat, another HIF-PH inhibitor, on thyroid function in patients with renal anemia in CKD.
    Methods: This retrospective observational study included a total of 26 patients with anemia in CKD who were treated with roxadustat or daprodustat; thyroid-stimulating hormone (TSH) and free thyroxine (FT4) were measured before and after treatment with the drugs.
    Results: After initiation of roxadustat, TSH showed a significant decrease (2.4732 [1.7858-4.9016] μIU/mL before treatment and 0.659 [0.112-2.005] μIU/mL after treatment, P < .05); FT4 showed a significant decrease (0.93 [0.84-1.05] ng/dL before treatment and 0.70 [0.53-0.85] ng/dL after treatment, P < .01). After daprodustat initiation, neither TSH nor FT4 showed a significant change (TSH: 3.044 [1.853-4.171] μIU/mL before treatment and 2.893 [1.866-4.894] μIU/mL after treatment, P = .635; FT4 was 0.93 [0.81-1.00] ng/dL before treatment and 0.97 [0.87-1.05] ng/dL after treatment, P = .328).
    Conclusion: Roxadustat decreases TSH and FT4 levels while daprodustat does not.
    MeSH term(s) Humans ; Anemia/drug therapy ; Anemia/etiology ; Isoquinolines/therapeutic use ; Renal Insufficiency, Chronic/complications ; Renal Insufficiency, Chronic/drug therapy ; Renal Insufficiency, Chronic/chemically induced ; Thyroid Gland/metabolism ; Thyrotropin/therapeutic use ; Retrospective Studies
    Chemical Substances Isoquinolines ; Thyrotropin (9002-71-5)
    Language English
    Publishing date 2023-08-18
    Publishing country United States
    Document type Observational Study ; Journal Article
    ZDB-ID 3029-6
    ISSN 1945-7197 ; 0021-972X
    ISSN (online) 1945-7197
    ISSN 0021-972X
    DOI 10.1210/clinem/dgad483
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Stimulatory effect of imeglimin on incretin secretion.

    Yingyue, Quan / Sugawara, Kenji / Takahashi, Harumi / Yokoi, Norihide / Ohbayashi, Kento / Iwasaki, Yusaku / Seino, Susumu / Ogawa, Wataru

    Journal of diabetes investigation

    2023  Volume 14, Issue 6, Page(s) 746–755

    Abstract: Aims/introduction: Imeglimin is a new antidiabetic drug structurally related to metformin. Despite this structural similarity, only imeglimin augments glucose-stimulated insulin secretion (GSIS), with the mechanism underlying this effect remaining ... ...

    Abstract Aims/introduction: Imeglimin is a new antidiabetic drug structurally related to metformin. Despite this structural similarity, only imeglimin augments glucose-stimulated insulin secretion (GSIS), with the mechanism underlying this effect remaining unclear. Given that glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) also enhance GSIS, we examined whether these incretin hormones might contribute to the pharmacological actions of imeglimin.
    Materials and methods: Blood glucose and plasma insulin, GIP, and GLP-1 concentrations were measured during an oral glucose tolerance test (OGTT) performed in C57BL/6JJcl (C57BL/6) or KK-Ay/TaJcl (KK-Ay) mice after administration of a single dose of imeglimin with or without the dipeptidyl peptidase-4 inhibitor sitagliptin or the GLP-1 receptor antagonist exendin-9. The effects of imeglimin, with or without GIP or GLP-1, on GSIS were examined in C57BL/6 mouse islets.
    Results: Imeglimin lowered blood glucose and increased plasma insulin levels during an OGTT in both C57BL/6 and KK-Ay mice, whereas it also increased the plasma levels of GIP and GLP-1 in KK-Ay mice and the GLP-1 levels in C57BL/6 mice. The combination of imeglimin and sitagliptin increased plasma insulin and GLP-1 levels during the OGTT in KK-Ay mice to a markedly greater extent than did either drug alone. Imeglimin enhanced GSIS in an additive manner with GLP-1, but not with GIP, in mouse islets. Exendin-9 had only a minor inhibitory effect on the glucose-lowering action of imeglimin during the OGTT in KK-Ay mice.
    Conclusions: Our data suggest that the imeglimin-induced increase in plasma GLP-1 levels likely contributes at least in part to its stimulatory effect on insulin secretion.
    MeSH term(s) Animals ; Mice ; Incretins/pharmacology ; Blood Glucose ; Insulin ; Mice, Inbred C57BL ; Sitagliptin Phosphate/pharmacology ; Hypoglycemic Agents/pharmacology ; Glucose/pharmacology ; Glucagon-Like Peptide 1 ; Gastric Inhibitory Polypeptide
    Chemical Substances Incretins ; Blood Glucose ; imeglimin (UU226QGU97) ; Insulin ; Sitagliptin Phosphate (TS63EW8X6F) ; Hypoglycemic Agents ; Glucose (IY9XDZ35W2) ; Glucagon-Like Peptide 1 (89750-14-1) ; Gastric Inhibitory Polypeptide (59392-49-3)
    Language English
    Publishing date 2023-03-28
    Publishing country Japan
    Document type Journal Article
    ZDB-ID 2625840-7
    ISSN 2040-1124 ; 2040-1116
    ISSN (online) 2040-1124
    ISSN 2040-1116
    DOI 10.1111/jdi.14001
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Increased glycolysis affects β-cell function and identity in aging and diabetes

    Naoya Murao / Norihide Yokoi / Harumi Takahashi / Tomohide Hayami / Yasuhiro Minami / Susumu Seino

    Molecular Metabolism, Vol 55, Iss , Pp 101414- (2022)

    2022  

    Abstract: Objective: Age is a risk factor for type 2 diabetes (T2D). We aimed to elucidate whether β-cell glucose metabolism is altered with aging and contributes to T2D. Methods: We used senescence-accelerated mice (SAM), C57BL/6J (B6) mice, and ob/ob mice as ... ...

    Abstract Objective: Age is a risk factor for type 2 diabetes (T2D). We aimed to elucidate whether β-cell glucose metabolism is altered with aging and contributes to T2D. Methods: We used senescence-accelerated mice (SAM), C57BL/6J (B6) mice, and ob/ob mice as aging models. As a diabetes model, we used db/db mice. The glucose responsiveness of insulin secretion and the [U-13C]-glucose metabolic flux were examined in isolated islets. We analyzed the expression of β-cell-specific genes in isolated islets and pancreatic sections as molecular signatures of β-cell identity. β cells defective in the malate-aspartate (MA) shuttle were previously generated from MIN6-K8 cells by the knockout of Got1, a component of the shuttle. We analyzed Got1 KO β cells as a model of increased glycolysis. Results: We identified hyperresponsiveness to glucose and compromised cellular identity as dysfunctional phenotypes shared in common between aged and diabetic mouse β cells. We also observed a metabolic commonality between aged and diabetic β cells: hyperactive glycolysis through the increased expression of nicotinamide mononucleotide adenylyl transferase 2 (Nmnat2), a cytosolic nicotinamide adenine dinucleotide (NAD)-synthesizing enzyme. Got1 KO β cells showed increased glycolysis, β-cell dysfunction, and impaired cellular identity, phenocopying aging and diabetes. Using Got1 KO β cells, we show that attenuation of glycolysis or Nmnat2 activity can restore β-cell function and identity. Conclusions: Our study demonstrates that hyperactive glycolysis is a metabolic signature of aged and diabetic β cells, which may underlie age-related β-cell dysfunction and loss of cellular identity. We suggest Nmnat2 suppression as an approach to counteract age-related T2D.
    Keywords Aging ; Diabetes ; β cells ; Insulin ; Glycolysis ; NAD ; Internal medicine ; RC31-1245
    Subject code 571 ; 570
    Language English
    Publishing date 2022-01-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Glutamate as intracellular and extracellular signals in pancreatic islet functions.

    Takahashi, Harumi / Yokoi, Norihide / Seino, Susumu

    Proceedings of the Japan Academy. Series B, Physical and biological sciences

    2019  Volume 95, Issue 6, Page(s) 246–260

    Abstract: l-Glutamate is one of the most abundant amino acids in the body and is a constituent of proteins and a substrate in metabolism. It is well known that glutamate serves as a primary excitatory neurotransmitter and a critical neuromodulator in the brain. ... ...

    Abstract l-Glutamate is one of the most abundant amino acids in the body and is a constituent of proteins and a substrate in metabolism. It is well known that glutamate serves as a primary excitatory neurotransmitter and a critical neuromodulator in the brain. Recent studies have shown that in addition to its pivotal role in neural functions, glutamate plays many important roles in a variety of cellular functions, including those as intracellular and extracellular signals. In pancreatic islets, glutamate is now known to be required for the normal regulation of insulin secretion, such as incretin-induced insulin secretion. In this review, we primarily discuss the physiological and pathophysiological roles of glutamate as intracellular and extracellular signals in the functions of pancreatic islets.
    MeSH term(s) Animals ; Extracellular Space/metabolism ; Glutamic Acid/metabolism ; Humans ; Intracellular Space/metabolism ; Islets of Langerhans/cytology ; Islets of Langerhans/metabolism ; Signal Transduction
    Chemical Substances Glutamic Acid (3KX376GY7L)
    Language English
    Publishing date 2019-06-11
    Publishing country Japan
    Document type Journal Article ; Review
    ZDB-ID 161781-3
    ISSN 1349-2896 ; 0386-2208
    ISSN (online) 1349-2896
    ISSN 0386-2208
    DOI 10.2183/pjab.95.017
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: O-GlcNAcylation of myocyte-specific enhancer factor 2D negatively regulates insulin secretion from pancreatic β-cells

    Yoshida, Mai / Yokoi, Norihide / Takahashi, Harumi / Hatano, Naoya / Hayami, Tomohide / Ogawa, Wataru / Seino, Susumu

    Biochemical and biophysical research communications. 2022 May 21, v. 605

    2022  

    Abstract: Patients with type 2 diabetes often exhibit impairments in both glucose-induced insulin secretion (GIIS) and incretin-induced insulin secretion (IIIS). These phenotypes are associated with altered glucose metabolism in pancreatic β-cells, although the ... ...

    Abstract Patients with type 2 diabetes often exhibit impairments in both glucose-induced insulin secretion (GIIS) and incretin-induced insulin secretion (IIIS). These phenotypes are associated with altered glucose metabolism in pancreatic β-cells, although the molecular mechanisms remain unclear. Here, we used MIN6-K8 pancreatic β-cell lines as a model to examine the effect of O-linked N-acetylglucosamine glycosylation (O-GlcNAcylation), a glucose-induced protein posttranslational modification, on insulin secretion. O-GlcNAcylation was enhanced in high-glucose-treated MIN6-K8 cells, and high levels of O-GlcNAcylation attenuated PKA-dependent phosphorylation, suggesting that the two protein modifications may compete with each other. Immunoprecipitation proteomic analysis identified six candidate proteins that were O-GlcNAcylated by high-glucose treatment, whereas the O-GlcNAcylations were removed by treatment with an incretin mimetic, exendin-4. Among these proteins, knockdown of myocyte enhancer factor 2D (Mef2d) enhanced insulin secretion, and high-glucose treatment increased the level of O-GlcNAcylation of Mef2d in MIN6-K8 cells. Furthermore, knockout of Mef2d promoted GIIS in MIN6-K8 cells, whereas adenovirus-mediated rescue of Mef2d decreased GIIS in the knockout cells. These results suggest that Mef2d negatively regulates insulin secretion through O-GlcNAcylation.
    Keywords N-acetylglucosamine ; glucose ; glycosylation ; insulin secretion ; noninsulin-dependent diabetes mellitus ; phosphorylation ; precipitin tests ; proteomics ; research ; secretin
    Language English
    Dates of publication 2022-0521
    Size p. 90-96.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 205723-2
    ISSN 0006-291X ; 0006-291X
    ISSN (online) 0006-291X
    ISSN 0006-291X
    DOI 10.1016/j.bbrc.2022.03.036
    Database NAL-Catalogue (AGRICOLA)

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