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Kim A, Zhang Z, Legros C, Lu Z, de Smith A, Moore JE, Mancuso N, Gazal S. Inferring causal cell types of human diseases and risk variants from candidate regulatory elements. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.05.17.24307556. [PMID: 38798383 PMCID: PMC11118635 DOI: 10.1101/2024.05.17.24307556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
The heritability of human diseases is extremely enriched in candidate regulatory elements (cRE) from disease-relevant cell types. Critical next steps are to infer which and how many cell types are truly causal for a disease (after accounting for co-regulation across cell types), and to understand how individual variants impact disease risk through single or multiple causal cell types. Here, we propose CT-FM and CT-FM-SNP, two methods that leverage cell-type-specific cREs to fine-map causal cell types for a trait and for its candidate causal variants, respectively. We applied CT-FM to 63 GWAS summary statistics (average N = 417K) using nearly one thousand cRE annotations, primarily coming from ENCODE4. CT-FM inferred 81 causal cell types with corresponding SNP-annotations explaining a high fraction of trait SNP-heritability (~2/3 of the SNP-heritability explained by existing cREs), identified 16 traits with multiple causal cell types, highlighted cell-disease relationships consistent with known biology, and uncovered previously unexplored cellular mechanisms in psychiatric and immune-related diseases. Finally, we applied CT-FM-SNP to 39 UK Biobank traits and predicted high confidence causal cell types for 2,798 candidate causal non-coding SNPs. Our results suggest that most SNPs impact a phenotype through a single cell type, and that pleiotropic SNPs target different cell types depending on the phenotype context. Altogether, CT-FM and CT-FM-SNP shed light on how genetic variants act collectively and individually at the cellular level to impact disease risk.
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Affiliation(s)
- Artem Kim
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Center for Genetic Epidemiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Zixuan Zhang
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Center for Genetic Epidemiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Come Legros
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Center for Genetic Epidemiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Zeyun Lu
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Center for Genetic Epidemiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Adam de Smith
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Center for Genetic Epidemiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Jill E Moore
- Department of Genomics and Computational Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Nicholas Mancuso
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Center for Genetic Epidemiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA, USA
| | - Steven Gazal
- Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Center for Genetic Epidemiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA, USA
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Singh M, Guru A, Pachaiappan R, Almutairi BO, Arokiyaraj S, Gopi M, Arockiaraj J. Impact of butylparaben on β-cell damage and insulin/PEPCK expression in zebrafish larvae: Protective effects of morin. J Biochem Mol Toxicol 2024; 38:e23520. [PMID: 37632306 DOI: 10.1002/jbt.23520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 08/07/2023] [Accepted: 08/17/2023] [Indexed: 08/27/2023]
Abstract
Butylparaben (BP), a common chemical preservative in cosmetic and pharmaceutical products, has been known to induce oxidative stress and disrupt endocrine function in humans. In contrast, morin, a flavonoid derived from the Moraceae family, exhibits diverse pharmacological properties, including anti-inflammatory and antioxidant. Despite this, the protective role of morin against oxidative stress-induced damage in pancreatic islets remains unclear. Therefore, in this study, we aimed to investigate the potential protective mechanism of morin against oxidative stress-induced damage caused by BP in zebrafish larvae. To achieve this, we exposed the zebrafish larvae to butylparaben (2.5 mg/L) for 5 days, leading to increased oxidative stress and apoptosis in β-cells. However, our compelling findings revealed that pretreatment with various concentrations of morin effectively reduced mortality and mitigated apoptosis and lipid peroxidation in β-cells induced by BP exposure. In addition, zebrafish larvae exposed to BP for 5 days exhibited evident β-cell damage. However, the pretreatment with morin showed promising effects by promoting β-cell proliferation and lowering glucose levels. Furthermore, gene expression studies indicated that morin pretreatment normalized PEPCK expression while increasing insulin expression in BP-exposed larvae. In conclusion, our findings highlight the potential of morin as a protective agent against BP-induced β-cell damage in zebrafish larvae. The observed improvements in oxidative stress, apoptosis, and gene expression patterns support the notion that morin could be further explored as a therapeutic candidate to counteract the detrimental effects of BP exposure on pancreatic β-cells.
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Affiliation(s)
- Mahima Singh
- Department of Biotechnology, School of Bioengineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Ajay Guru
- Department of Cariology, Saveetha Dental College and Hospitals, SIMATS, Chennai, Tamil Nadu, India
| | - Raman Pachaiappan
- Department of Biotechnology, School of Bioengineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Bader O Almutairi
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Selvaraj Arokiyaraj
- Department of Food Science & Biotechnology, Sejong University, Seoul, South Korea
| | - Muthukaruppan Gopi
- Department of Biotechnology, School of Bioengineering, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Jesu Arockiaraj
- Toxicology and Pharmacology Laboratory, Department of Biotechnology, Faculty of Science and Humanities, SRM Institute of Science and Technology, Kattankulatur, Tamil Nadu, India
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Zaïmia N, Obeid J, Varrault A, Sabatier J, Broca C, Gilon P, Costes S, Bertrand G, Ravier MA. GLP-1 and GIP receptors signal through distinct β-arrestin 2-dependent pathways to regulate pancreatic β cell function. Cell Rep 2023; 42:113326. [PMID: 37897727 DOI: 10.1016/j.celrep.2023.113326] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 09/14/2023] [Accepted: 10/07/2023] [Indexed: 10/30/2023] Open
Abstract
Glucagon-like peptide 1 (GLP-1R) and glucose-dependent insulinotropic polypeptide (GIPR) receptors are G-protein-coupled receptors involved in glucose homeostasis. Diabetogenic conditions decrease β-arrestin 2 (ARRB2) levels in human islets. In mouse β cells, ARRB2 dampens insulin secretion by partially uncoupling cyclic AMP (cAMP)/protein kinase A (PKA) signaling at physiological doses of GLP-1, whereas at pharmacological doses, the activation of extracellular signal-related kinase (ERK)/cAMP-responsive element-binding protein (CREB) requires ARRB2. In contrast, GIP-potentiated insulin secretion needs ARRB2 in mouse and human islets. The GIPR-ARRB2 axis is not involved in cAMP/PKA or ERK signaling but does mediate GIP-induced F-actin depolymerization. Finally, the dual GLP-1/GIP agonist tirzepatide does not require ARRB2 for the potentiation of insulin secretion. Thus, ARRB2 plays distinct roles in regulating GLP-1R and GIPR signaling, and we highlight (1) its role in the physiological context and the possible functional consequences of its decreased expression in pathological situations such as diabetes and (2) the importance of assessing the signaling pathways engaged by the agonists (biased/dual) for therapeutic purposes.
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Affiliation(s)
- Nour Zaïmia
- IGF, Université Montpellier, CNRS, INSERM, Montpellier, France
| | - Joelle Obeid
- IGF, Université Montpellier, CNRS, INSERM, Montpellier, France
| | - Annie Varrault
- IGF, Université Montpellier, CNRS, INSERM, Montpellier, France
| | | | | | - Patrick Gilon
- Université Catholique de Louvain, Institut de Recherche Expérimental et Clinique, Pôle d'Endocrinologie, Diabète, et Nutrition, Brussels, Belgium
| | - Safia Costes
- IGF, Université Montpellier, CNRS, INSERM, Montpellier, France
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Rao PV, Bean E, Nair-Schaef D, Chen S, Kazmierczak SC, Roberts CT, Nagalla SR. Rapid Point-of-Care Test for Determination of C-Peptide Levels. J Diabetes Sci Technol 2022; 16:976-981. [PMID: 33729032 PMCID: PMC9264426 DOI: 10.1177/1932296821995557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
C-peptide is co-secreted with insulin and is not subject to hepatic clearance and thus reflects functional β-cell mass. Assessment of C-peptide levels can identify individuals at risk for or with type 1 diabetes with residual β-cell function in whom β cell-sparing interventions can be evaluated, and can aid in distinguishing type 2 diabetes from Latent Autoimmune Diabetes in Adults and late-onset type 1 diabetes. To facilitate C-peptide testing, we describe a quantitative point-of-care C-peptide test. C-peptide levels as low as 0.2 ng/ml were measurable in a fingerstick sample, and the test was accurate over a range of 0.17 to 12.0 ng/ml. This test exhibited a correlation of r = 0.98 with a high-sensitivity commercial ELISA assay and a correlation of r = 0.90 between matched serum and fingerstick samples.
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Affiliation(s)
| | - Eric Bean
- Diabetomics, Inc., Hillsboro, OR,
USA
| | | | - Siting Chen
- School of Public Health, Oregon Health
& Science University, Portland, OR, USA
| | | | | | - Srinivasa R. Nagalla
- Diabetomics, Inc., Hillsboro, OR,
USA
- Srinivasa R. Nagalla, MD, Diabetomics, Inc.,
2345 NE Overlook Dr., Hillsboro, OR 97006, USA.
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Abstract
PCOS is a common and heterogeneous endocrine disorder in women of reproductive age, frequently associated with metabolic abnormalities. It was estimated that about 75% of these subjects have an impairment of insulin action, as measured by gold standard methods. While the relationship between insulin resistance and PCOS is consistently shown by a number of studies, the mechanisms underlying its primary origin still remains an unsolved issue. Insulin resistance and the associated hyperinsulinemia can induce both the endocrine and reproductive traits of PCOS. However, androgen excess, in turn, can impair insulin action, directly and/or through several changes occurring in different tissues. Body fat excess, which is another common feature in these women, can contribute to worsening the whole picture. Nevertheless, insulin resistance may also be found in many normal-weight individuals. Endocrine and metabolic abnormalities can develop in different moments, and probably there is fetal programming of these alterations. However, a number of vicious circles, with bidirectional relationships between androgen excess and insulin resistance, and with the contribution of several other factors, make it extremely difficult to understand where this process really originates. This review summarizes available evidence on this topic, in order to better understand the complex relationships linking hyperandrogenism and impaired insulin action in women with PCOS.
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Affiliation(s)
- P Moghetti
- Unit of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Verona and Azienda Ospedaliera Universitaria Integrata Verona, P.le Stefani, 1, 37126, Verona, Italy.
| | - F Tosi
- Unit of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Verona and Azienda Ospedaliera Universitaria Integrata Verona, P.le Stefani, 1, 37126, Verona, Italy
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Resveratrol Prevents GLUT3 Up-Regulation Induced by Middle Cerebral Artery Occlusion. Brain Sci 2020; 10:brainsci10090651. [PMID: 32962200 PMCID: PMC7563146 DOI: 10.3390/brainsci10090651] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 09/07/2020] [Accepted: 09/18/2020] [Indexed: 12/21/2022] Open
Abstract
Glucose transporter (GLUT)3 up-regulation is an adaptive response activated to prevent cellular damage when brain metabolic energy is reduced. Resveratrol is a natural polyphenol with anti-oxidant and anti-inflammatory features that protects neurons against damage induced in cerebral ischemia. Since transcription factors sensitive to oxidative stress and inflammation modulate GLUT3 expression, the purpose of this work was to assess the effect of resveratrol on GLUT3 expression levels after ischemia. Male Wistar rats were subjected to 2 h of middle cerebral artery occlusion (MCAO) followed by different times of reperfusion. Resveratrol (1.9 mg/kg; i. p.) was administered at the onset of the restoration of the blood flow. Quantitative-PCR and Western blot showed that MCAO provoked a substantial increase in GLUT3 expression in the ipsilateral side to the lesion of the cerebral cortex. Immunofluorescence assays indicated that GLUT3 levels were upregulated in astrocytes. Additionally, an important increase in GLUT3 occurred in other cellular types (e.g., damaged neurons, microglia, or infiltrated macrophages). Immunodetection of the microtubule-associated protein 2 (MAP2) showed that MCAO induced severe damage to the neuronal population. However, the administration of resveratrol at the time of reperfusion resulted in injury reduction. Resveratrol also prevented the MCAO-induced increase of GLUT3 expression. In conclusion, resveratrol protects neurons from damage induced by ischemia and prevents GLUT3 upregulation in the damaged brain that might depend on AMPK activation.
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Hou G, Tang Y, Ren L, Guan Y, Hou X, Song G. The ANGPTL8 rs2278426 (C/T) Polymorphism Is Associated with Prediabetes and Type 2 Diabetes in a Han Chinese Population in Hebei Province. Int J Endocrinol 2020; 2020:1621239. [PMID: 33343659 PMCID: PMC7728483 DOI: 10.1155/2020/1621239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/14/2020] [Accepted: 11/23/2020] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Our aim was to investigate the association between the genetics of the angiopoietin protein-like 8 (ANGPTL8) rs2278426 (C/T) polymorphism with prediabetes (pre-DM) and type 2 diabetes (T2DM) in a Han Chinese population in Hebei Province, China. METHODS We enrolled 1,460 participants into this case-control study: healthy controls, n = 524; pre-DM, n = 460; and T2DM: n = 460. Ligase assays on blood samples from all participants were used to identify polymorphisms. Differences in genotype and allele distributions were compared by the chi-square test and one-way analysis of variance, and a post hoc pairwise analysis was performed using the Bonferroni test. The logistic regression technique was adjusted for age, sex, and body mass index. RESULTS The frequency of the TT (10.9%) genotype was significantly higher in pre-DM patients than in controls (odds ratio [OR] = 1.696, 95% confidence interval [CI] = 1.026-2.802, P=0.039). In the T2DM group, the CT (48%) and TT (15%) genotypes were significantly higher compared with those in the control group (CT : OR = 1.384, 95% CI = 1.013-1.890, P=0.041; TT : OR = 2.530, 95% CI = 1.476-4.334, P=0.001). The frequency of the T allele was significantly higher in the pre-DM (32.8%) and T2DM (39%) groups compared with the control group (26.9%) and was significantly associated with an increased risk of pre-DM (OR = 1.253, 95% CI = 1.017-1.544, P=0.034) and T2DM (OR = 1.518, 95% CI = 1.214-1.897, P=0.001). Furthermore, insulin levels in the pre-DM and T2DM groups were significantly decreased in those with the TT genotype compared with the CC and CT genotypes. CONCLUSION ANGPTL8 rs2278426 may be involved in the mechanism of insulin secretion and could lead to an increased risk of pre-DM and T2DM.
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Affiliation(s)
- Guangsen Hou
- Department of Internal Medicine, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Yong Tang
- Endocrinology Department, Hebei General Hospital, Shijiazhuang, Hebei 050051, China
| | - Luping Ren
- Endocrinology Department, Hebei General Hospital, Shijiazhuang, Hebei 050051, China
| | - Yunpeng Guan
- Department of Internal Medicine, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Xiaoyu Hou
- Department of Internal Medicine, Hebei Medical University, Shijiazhuang, Hebei 050017, China
| | - Guangyao Song
- Department of Internal Medicine, Hebei Medical University, Shijiazhuang, Hebei 050017, China
- Endocrinology Department, Hebei General Hospital, Shijiazhuang, Hebei 050051, China
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Burke SJ, Batdorf HM, Huang TY, Jackson JW, Jones KA, Martin TM, Rohli KE, Karlstad MD, Sparer TE, Burk DH, Campagna SR, Noland RC, Soto PL, Collier JJ. One week of continuous corticosterone exposure impairs hepatic metabolic flexibility, promotes islet β-cell proliferation, and reduces physical activity in male C57BL/6 J mice. J Steroid Biochem Mol Biol 2019; 195:105468. [PMID: 31536768 PMCID: PMC6939671 DOI: 10.1016/j.jsbmb.2019.105468] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Revised: 08/28/2019] [Accepted: 09/05/2019] [Indexed: 10/26/2022]
Abstract
Clinical glucocorticoid use, and diseases that produce elevated circulating glucocorticoids, promote drastic changes in body composition and reduction in whole body insulin sensitivity. Because steroid-induced diabetes is the most common form of drug-induced hyperglycemia, we investigated mechanisms underlying the recognized phenotypes associated with glucocorticoid excess. Male C57BL/6 J mice were exposed to either 100ug/mL corticosterone (cort) or vehicle in their drinking water. Body composition measurements revealed an increase in fat mass with drastically reduced lean mass during the first week (i.e., seven days) of cort exposure. Relative to the vehicle control group, mice receiving cort had a significant reduction in insulin sensitivity (measured by insulin tolerance test) five days after drug intervention. The increase in insulin resistance significantly correlated with an increase in the number of Ki-67 positive β-cells. Moreover, the ability to switch between fuel sources in liver tissue homogenate substrate oxidation assays revealed reduced metabolic flexibility. Furthermore, metabolomics analyses revealed a decrease in liver glycolytic metabolites, suggesting reduced glucose utilization, a finding consistent with onset of systemic insulin resistance. Physical activity was reduced, while respiratory quotient was increased, in mice receiving corticosterone. The majority of metabolic changes were reversed upon cessation of the drug regimen. Collectively, we conclude that changes in body composition and tissue level substrate metabolism are key components influencing the reductions in whole body insulin sensitivity observed during glucocorticoid administration.
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Affiliation(s)
- Susan J Burke
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, United States
| | - Heidi M Batdorf
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, United States
| | - Tai-Yu Huang
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, United States
| | - Joseph W Jackson
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, United States
| | - Katarina A Jones
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996, United States
| | - Thomas M Martin
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, United States; Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, United States
| | - Kristen E Rohli
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, United States; Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, United States
| | - Michael D Karlstad
- Department of Surgery, University of Tennessee Health Science Center, Knoxville, TN 37920, United States
| | - Tim E Sparer
- Department of Microbiology, University of Tennessee, Knoxville, TN 37996, United States
| | - David H Burk
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, United States
| | - Shawn R Campagna
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996, United States
| | - Robert C Noland
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, United States
| | - Paul L Soto
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, United States; Department of Psychology, Louisiana State University, Baton Rouge, LA 70803, United States
| | - J Jason Collier
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, United States; Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, United States.
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Macdougall CE, Wood EG, Solomou A, Scagliotti V, Taketo MM, Gaston-Massuet C, Marelli-Berg FM, Charalambous M, Longhi MP. Constitutive Activation of β-Catenin in Conventional Dendritic Cells Increases the Insulin Reserve to Ameliorate the Development of Type 2 Diabetes in Mice. Diabetes 2019; 68:1473-1484. [PMID: 31048369 DOI: 10.2337/db18-1243] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 04/11/2019] [Indexed: 11/13/2022]
Abstract
β-Cell failure is central to the development of type 2 diabetes mellitus (T2DM). Dysregulation of metabolic and inflammatory processes during obesity contributes to the loss of islet function and impaired β-cell insulin secretion. Modulating the immune system, therefore, has the potential to ameliorate diseases. We report that inducing sustained expression of β-catenin in conventional dendritic cells (cDCs) provides a novel mechanism to enhance β-cell insulin secretion. Intriguingly, cDCs with constitutively activated β-catenin induced islet expansion by increasing β-cell proliferation in a model of diet-induced obesity. We further found that inflammation in these islets was reduced. Combined, these effects improved β-cell insulin secretion, suggesting a unique compensatory mechanism driven by cDCs to generate a greater insulin reserve in response to obesity-induced insulin resistance. Our findings highlight the potential of immune modulation to improve β-cell mass and function in T2DM.
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Affiliation(s)
- Claire E Macdougall
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, U.K
| | - Elizabeth G Wood
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, U.K
| | - Antonia Solomou
- Department of Medical and Molecular Genetics, King's College London, Guys Hospital, London, U.K
| | - Valeria Scagliotti
- Department of Medical and Molecular Genetics, King's College London, Guys Hospital, London, U.K
| | - Makoto Mark Taketo
- Division of Experimental Therapeutics, Graduate School of Medicine, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Carles Gaston-Massuet
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, U.K
| | - Federica M Marelli-Berg
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, U.K
| | - Marika Charalambous
- Department of Medical and Molecular Genetics, King's College London, Guys Hospital, London, U.K
| | - M Paula Longhi
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, U.K.
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Arunagiri A, Haataja L, Pottekat A, Pamenan F, Kim S, Zeltser LM, Paton AW, Paton JC, Tsai B, Itkin-Ansari P, Kaufman RJ, Liu M, Arvan P. Proinsulin misfolding is an early event in the progression to type 2 diabetes. eLife 2019; 8:44532. [PMID: 31184302 PMCID: PMC6559786 DOI: 10.7554/elife.44532] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 04/09/2019] [Indexed: 02/06/2023] Open
Abstract
Biosynthesis of insulin – critical to metabolic homeostasis – begins with folding of the proinsulin precursor, including formation of three evolutionarily conserved intramolecular disulfide bonds. Remarkably, normal pancreatic islets contain a subset of proinsulin molecules bearing at least one free cysteine thiol. In human (or rodent) islets with a perturbed endoplasmic reticulum folding environment, non-native proinsulin enters intermolecular disulfide-linked complexes. In genetically obese mice with otherwise wild-type islets, disulfide-linked complexes of proinsulin are more abundant, and leptin receptor-deficient mice, the further increase of such complexes tracks with the onset of islet insulin deficiency and diabetes. Proinsulin-Cys(B19) and Cys(A20) are necessary and sufficient for the formation of proinsulin disulfide-linked complexes; indeed, proinsulin Cys(B19)-Cys(B19) covalent homodimers resist reductive dissociation, highlighting a structural basis for aberrant proinsulin complex formation. We conclude that increased proinsulin misfolding via disulfide-linked complexes is an early event associated with prediabetes that worsens with ß-cell dysfunction in type two diabetes. Our body fine-tunes the amount of sugar in our blood thanks to specialized ‘beta cells’ in the pancreas, which can release a hormone called insulin. To produce insulin, the beta cells first need to build an early version of the molecule – known as proinsulin – inside a cellular compartment called the endoplasmic reticulum. This process involves the formation of internal staples that keep the molecule of proinsulin folded correctly. Individuals developing type 2 diabetes have spikes of sugar in their blood, and so their bodies often respond by trying to make large amounts of insulin. After a while, the beta cells can fail to keep up, which brings on the full-blown disease. However, scientists have discovered that early in type 2 diabetes, the endoplasmic reticulum of beta cells can already show signs of stress; yet, the exact causes of this early damage are still unknown. To investigate this, Arunagiri et al. looked into whether proinsulin folds correctly during the earliest stages of type 2 diabetes. Biochemical experiments showed that even healthy beta cells contained some misfolded proinsulin molecules, where the molecular staples that should fold proinsulin internally were instead abnormally linking proinsulin molecules together. Further work revealed that the misfolded proinsulin was accumulating inside the endoplasmic reticulum. Finally, obese mice that were in the earliest stages of type 2 diabetes had the highest levels of abnormal proinsulin in their beta cells. Overall, the work by Arunagiri et al. suggests that large amounts of proinsulin molecules stapling themselves to each other in the endoplasmic reticulum of beta cells could be an early hallmark of the disease, and could make it get worse. A separate study by Jang et al. also shows that a protein that limits the misfolding of proinsulin is key to maintain successful insulin production in animals eating a Western-style, high fat diet. Hundreds of millions of people around the world have type 2 diabetes, and this number is rising quickly. Detecting and then fixing early problems associated with the condition may help to stop the disease in its track.
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Affiliation(s)
- Anoop Arunagiri
- Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, United States
| | - Leena Haataja
- Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, United States
| | - Anita Pottekat
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, United States
| | - Fawnnie Pamenan
- Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, United States
| | - Soohyun Kim
- Department of Biomedical Science and Technology, Konkuk University, Gwangjin-gu, Republic of Korea
| | - Lori M Zeltser
- Department of Pathology and Cell Biology, Naomi Berrie Diabetes Center, Columbia University, New York, United States
| | - Adrienne W Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, Adelaide, Australia
| | - James C Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, Adelaide, Australia
| | - Billy Tsai
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, United States
| | - Pamela Itkin-Ansari
- Development, Aging and Regeneration Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, United States
| | - Randal J Kaufman
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, United States
| | - Ming Liu
- Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, United States.,Department of Endocrinology and Metabolism, Tianjin Medical University, Tianjin, China
| | - Peter Arvan
- Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, United States
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11
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MicroRNA-125b-5p improves pancreatic β-cell function through inhibiting JNK signaling pathway by targeting DACT1 in mice with type 2 diabetes mellitus. Life Sci 2019; 224:67-75. [PMID: 30684546 DOI: 10.1016/j.lfs.2019.01.031] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 01/08/2019] [Accepted: 01/18/2019] [Indexed: 11/23/2022]
Abstract
Type 2 diabetes mellitus (T2DM) is a progressive disease, accompanied by increased insulin resistance and deteriorating β-cell function. Previous studies have revealed that microRNA (miRNA) plays a crucial role in the treatment of T2DM. Hence, we aim to investigate the role of microRNA-125b-5p (miR-125b-5p) in pancreatic β-cell function and insulin sensitivity of mice with T2DM with the involvement of Dishevelled antagonist Dapper1 (DACT1) and the c-Jun NH2-terminal kinases (JNK) signaling pathway. Firstly, a mouse model of T2DM was established by administering a high-fat diet plus low dosage of streptozotocin, and function of pancreatic β-cell and insulin sensitivity in the normal and T2DM mice were detected. Then, the pancreatic β-cells were collected from pancreatic islet tissues and treated with different mimics, inhibitors and siRNAs. After that, the relationship among miR-125b-5p, DACT1, and the JNK signaling-related factors in T2DM mice was determined. Finally, cell proliferation and apoptosis were determined. Mice with T2DM had lower pancreatic β-cell function and insulin sensitivity, as well as diminished expression of miR-125b-5p but enhanced expressions of DACT1, JNK and c-Jun. miR-125b-5p inhibited DACT1 expression and the activation of the JNK signaling pathway, as well as restrained cell proliferation and promoted cell apoptosis. The current results suggest that up-regulated miR-125b-5p promotes insulin sensitivity and enhances pancreatic β-cell function through inhibiting the JNK signaling pathway by negatively mediating DACT1.
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12
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Mazumdar M. Does arsenic increase the risk of neural tube defects among a highly exposed population? A new case-control study in Bangladesh. Birth Defects Res 2018; 109:92-98. [PMID: 27801974 DOI: 10.1002/bdra.23577] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 08/01/2016] [Accepted: 08/12/2016] [Indexed: 12/16/2022]
Abstract
BACKGROUND Neural tube defects are debilitating birth defects that occur when the developing neural plate fails to close in early gestation. Arsenic induces neural tube defects in animal models, but whether environmental arsenic exposure increases risk of neural tube defects in humans is unknown. METHODS We describe a new case-control study in Bangladesh, a country currently experiencing an epidemic of arsenic poisoning through contaminated drinking water. We plan to understand how arsenic influences risk of neural tube defects in humans through mechanisms that include disruption of maternal glucose and folate metabolism, as well as epigenetic effects. We also investigate whether sweat chloride concentration, a potential new biomarker for arsenic toxicity, can be used to identify women at higher risk for having a child affected by neural tube defect. We will collect dural tissue from cases, obtained at the time of surgical closure of the defect, and believe investigation of these samples will provide insight into the epigenetic mechanisms by which prenatal arsenic exposure affects the developing nervous system. CONCLUSION These studies explore mechanisms by which arsenic may increase risk of neural tube defects in humans and use a unique population with high arsenic exposure to test hypotheses. If successful, these studies may assist countries with high arsenic exposure such as Bangladesh to identify populations at high risk of neural tube defects, as well as direct development of novel screening strategies for maternal risk.Birth Defects Research 109:92-98, 2017.© 2016 The Authors Birth Defects Research Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Maitreyi Mazumdar
- Department of Neurology, Boston Children's Hospital, Boston, Massachusetts.,Department of Neurology, Harvard Medical School, Boston, Massachusetts.,Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts
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13
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Ottosson-Laakso E, Krus U, Storm P, Prasad RB, Oskolkov N, Ahlqvist E, Fadista J, Hansson O, Groop L, Vikman P. Glucose-Induced Changes in Gene Expression in Human Pancreatic Islets: Causes or Consequences of Chronic Hyperglycemia. Diabetes 2017; 66:3013-3028. [PMID: 28882899 DOI: 10.2337/db17-0311] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 08/30/2017] [Indexed: 11/13/2022]
Abstract
Dysregulation of gene expression in islets from patients with type 2 diabetes (T2D) might be causally involved in the development of hyperglycemia, or it could develop as a consequence of hyperglycemia (i.e., glucotoxicity). To separate the genes that could be causally involved in pathogenesis from those likely to be secondary to hyperglycemia, we exposed islets from human donors to normal or high glucose concentrations for 24 h and analyzed gene expression. We compared these findings with gene expression in islets from donors with normal glucose tolerance and hyperglycemia (including T2D). The genes whose expression changed in the same direction after short-term glucose exposure, as in T2D, were considered most likely to be a consequence of hyperglycemia. Genes whose expression changed in hyperglycemia but not after short-term glucose exposure, particularly those that also correlated with insulin secretion, were considered the strongest candidates for causal involvement in T2D. For example, ERO1LB, DOCK10, IGSF11, and PRR14L were downregulated in donors with hyperglycemia and correlated positively with insulin secretion, suggesting a protective role, whereas TMEM132C was upregulated in hyperglycemia and correlated negatively with insulin secretion, suggesting a potential pathogenic role. This study provides a catalog of gene expression changes in human pancreatic islets after exposure to glucose.
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Affiliation(s)
- Emilia Ottosson-Laakso
- Lund University Diabetes Centre, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Ulrika Krus
- Lund University Diabetes Centre, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Petter Storm
- Lund University Diabetes Centre, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Rashmi B Prasad
- Lund University Diabetes Centre, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Nikolay Oskolkov
- Lund University Diabetes Centre, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Emma Ahlqvist
- Lund University Diabetes Centre, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - João Fadista
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
| | - Ola Hansson
- Lund University Diabetes Centre, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Leif Groop
- Lund University Diabetes Centre, Department of Clinical Sciences, Lund University, Malmö, Sweden
- Finnish Institute of Molecular Medicine, University of Helsinki, Helsinki, Finland
| | - Petter Vikman
- Lund University Diabetes Centre, Department of Clinical Sciences, Lund University, Malmö, Sweden
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14
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Abu-Farha M, Abubaker J, Tuomilehto J. ANGPTL8 (betatrophin) role in diabetes and metabolic diseases. Diabetes Metab Res Rev 2017; 33. [PMID: 28722798 DOI: 10.1002/dmrr.2919] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 05/30/2017] [Accepted: 07/04/2017] [Indexed: 12/22/2022]
Abstract
Diabetes is a major disease worldwide that is reaching epidemic levels. Its increased prevalence as well as its association with a high number of complications such as cardiovascular diseases, nephropathy, and retinopathy makes it an important disease for investigation. ANGPTL8 is a recently identified hormone that has been associated with two functionally important processes in the development of type 2 diabetes, insulin resistance as well as lipid metabolism. Initial work has shown that ANGPTL8 was expressed in liver, white adipose, and brown adipose tissues. ANGPTL8 regulates the activity of lipoprotein lipase, which is a key enzyme in lipoprotein lipolysis pathway through its direct interaction with ANGPTL3. It has been also reported that it regulates the replication of β-cells in response to insulin resistance. As a result, many recent studies have focused on the association of ANGPTL8 with diabetes and obesity as well as its association with various metabolic markers in order to better understand its physiological role in glucose homeostasis and lipid metabolism. In this review, we will highlight some of the key clinical findings, mainly from human studies, that investigated the role of ANGPTL8 in metabolic diseases such as diabetes, obesity, and the metabolic syndrome.
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Affiliation(s)
- Mohamed Abu-Farha
- Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait
| | - Jehad Abubaker
- Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait
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15
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Protective effects of tea, red wine and cocoa in diabetes. Evidences from human studies. Food Chem Toxicol 2017; 109:302-314. [PMID: 28893620 DOI: 10.1016/j.fct.2017.09.015] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/14/2022]
Abstract
Prevention of diabetes through the diet has recently received an increasing interest, and polyphenolic compounds, such as flavanols, have become important potential chemopreventive natural agents due to their proved benefits on health, with low toxicity and cost. Tea, red wine and cocoa are good sources of flavanols and these highly consumed foods might contribute to prevent diabetes. In this regard, there is increasing evidence for a protective effect of tea, red wine and cocoa consumption against this disorder. This review summarizes the available epidemiological and interventional human studies providing evidence for and against this effect. Overall observational data suggest a benefit, but results are still equivocal and likely confounded by lifestyle and background dietary factors. The weight of data indicate favourable effects on diabetes risk factors for tea, red wine and cocoa intake, and a number of plausible mechanisms have been elucidated in human studies. However, despite the growing evidence it remains uncertain whether tea, red wine and cocoa consumption should be recommended to the general population or to patients as a strategy to reduce the risk of diabetes.
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16
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Gene-Diet Interactions in Type 2 Diabetes: The Chicken and Egg Debate. Int J Mol Sci 2017; 18:ijms18061188. [PMID: 28574454 PMCID: PMC5486011 DOI: 10.3390/ijms18061188] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 05/23/2017] [Accepted: 05/26/2017] [Indexed: 02/07/2023] Open
Abstract
Consistent evidence from both experimental and human studies indicates that Type 2 diabetes mellitus (T2DM) is a complex disease resulting from the interaction of genetic, epigenetic, environmental, and lifestyle factors. Nutrients and dietary patterns are important environmental factors to consider in the prevention, development and treatment of this disease. Nutritional genomics focuses on the interaction between bioactive food components and the genome and includes studies of nutrigenetics, nutrigenomics and epigenetic modifications caused by nutrients. There is evidence supporting the existence of nutrient-gene and T2DM interactions coming from animal studies and family-based intervention studies. Moreover, many case-control, cohort, cross-sectional cohort studies and clinical trials have identified relationships between individual genetic load, diet and T2DM. Some of these studies were on a large scale. In addition, studies with animal models and human observational studies, in different countries over periods of time, support a causative relationship between adverse nutritional conditions during in utero development, persistent epigenetic changes and T2DM. This review provides comprehensive information on the current state of nutrient-gene interactions and their role in T2DM pathogenesis, the relationship between individual genetic load and diet, and the importance of epigenetic factors in influencing gene expression and defining the individual risk of T2DM.
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17
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Ozbayer C, Degirmenci I, Kurt H, Kebapci MN, Colak E, Gunes HV. The rs1043994 and rs3815188 genetic variations of the NOTCH3 gene and risk of type 2 diabetes mellitus. BIOTECHNOL BIOTEC EQ 2017. [DOI: 10.1080/13102818.2017.1294034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Affiliation(s)
- Cansu Ozbayer
- School of Health Sciences, Dumlupinar University, Kutahya, Turkey
| | - Irfan Degirmenci
- Department of Medical Biology, Medical Faculty, Eskisehir Osmangazi University, Eskisehir, Turkey
| | - Hulyam Kurt
- Department of Medical Biology, Medical Faculty, Eskisehir Osmangazi University, Eskisehir, Turkey
| | - Medine Nur Kebapci
- Department of Endocrinology, Medical Faculty, Eskisehir Osmangazi University, Eskisehir, Turkey
| | - Ertugrul Colak
- Department of Biostatistics and Medical Informatics, Medical Faculty, Eskisehir Osmangazi University, Eskisehir, Turkey
| | - Hasan Veysi Gunes
- Department of Medical Biology, Medical Faculty, Eskisehir Osmangazi University, Eskisehir, Turkey
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18
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Oetjen E. Regulation of Beta-Cell Function and Mass by the Dual Leucine Zipper Kinase. Arch Pharm (Weinheim) 2016; 349:410-3. [PMID: 27100796 DOI: 10.1002/ardp.201600053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 03/14/2016] [Accepted: 03/18/2016] [Indexed: 01/09/2023]
Abstract
Diabetes mellitus is one of the most rapidly increasing diseases worldwide, whereby approximately 90-95% of patients suffer from type 2 diabetes. Considering its micro- and macrovascular complications like blindness and myocardial infarction, a reliable anti-diabetic treatment is needed. Maintaining the function and the mass of the insulin producing beta-cells despite elevated levels of beta-cell-toxic prediabetic signals represents a desirable mechanism of action of anti-diabetic drugs. The dual leucine zipper kinase (DLK) inhibits the action of two transcription factors within the beta-cell, thereby interfering with insulin secretion and production and the conservation of beta-cell mass. Furthermore, DLK action is regulated by prediabetic signals. Hence, the inhibition of this kinase might protect beta-cells against beta-cell-toxic prediabetic signals and prevent the development of diabetes. DLK might thus present a novel drug target for the treatment of diabetes mellitus type 2.
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Affiliation(s)
- Elke Oetjen
- Department of Clinical Pharmacology and Toxicology, Pharmacology for Pharmacist's Unit, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,DZHK (German Centre for Cardiovascular Research) Partner Site Hamburg/Kiel/Lübeck, Germany.,Institute of Pharmacy, University of Hamburg, Hamburg, Germany
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19
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Kihira Y, Burentogtokh A, Itoh M, Izawa-Ishizawa Y, Ishizawa K, Ikeda Y, Tsuchiya K, Tamaki T. Hypoxia decreases glucagon-like peptide-1 secretion from the GLUTag cell line. Biol Pharm Bull 2016; 38:514-21. [PMID: 25832631 DOI: 10.1248/bpb.b14-00612] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Glucagon-like peptide-1 (GLP-1), an incretin hormone, is secreted from L cells located in the intestinal epithelium. It is known that intestinal oxygen tension is decreased postprandially. In addition, we found that the expression of hypoxia-inducible factor-1α (HIF-1α), which accumulates in cells under hypoxic conditions, was significantly increased in the colons of mice with food intake, indicating that the oxygen concentration is likely reduced in the colon after eating. Therefore, we hypothesized that GLP-1 secretion is affected by oxygen tension. We found that forskolin-stimulated GLP-1 secretion from GLUTag cells, a model of intestinal L cells, is suppressed in hypoxia (1% O2). Forskolin-stimulated elevations of preproglucagon (ppGCG) and proprotein convertase 1/3 (PC1/3) mRNA expression were decreased under hypoxic conditions. The finding that H89, a protein kinase A (PKA) inhibitor, inhibited the forskolin-stimulated increase of ppGCG and PC1/3 indicated that the cAMP-PKA pathway is involved in the hypoxia-induced suppression of the genes. Hypoxia decreased hexokinase 2 mRNA and protein expression and increased lactate dehydrogenase A mRNA and protein expression. Concomitantly, lactate production was increased and ATP production was decreased. Together, the results indicate that hypoxia decreases glucose utilization for ATP production, which probably causes a decrease in cAMP production and in subsequent GLP-1 production. Our findings suggest that the postprandial decrease in oxygen tension in the intestine attenuates GLP-1 secretion.
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Affiliation(s)
- Yoshitaka Kihira
- Department of Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School
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20
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Song Y, Wan X, Gao L, Pan Y, Xie W, Wang H, Guo J. Activated PKR inhibits pancreatic β-cell proliferation through sumoylation-dependent stabilization of P53. Mol Immunol 2015; 68:341-9. [PMID: 26446704 DOI: 10.1016/j.molimm.2015.09.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 08/27/2015] [Accepted: 09/02/2015] [Indexed: 12/20/2022]
Abstract
Double-stranded RNA-dependent protein kinase (PKR) is intimately involved in type 2 diabetes due to its role in insulin resistance in peripheral tissues and anti-proliferative effect on pancreatic β-cells. Activated PKR was found to inhibit β-cell proliferation, partially through accumulation of P53. However the molecular mechanisms underlying PKR-dependent upregulation of P53 remain unknown. The results of the present study showed that PKR can be specifically activated in PKR overexpressing β-cells by a low dosage of the previously synthesized compound 1H-benzimidazole1-ethanol,2,3-dihydro-2-imino-a-(phenoxymethyl)-3-(phenylmethyl)-,monohydrochloride (BEPP), and this led to upregulation of P53 through sumoylation-dependent stability. Activated PKR was found to interact with sumo-conjugating enzyme Ubc9, and P53 sumoylation relies on a PKR-Ubc9 protein-protein interaction. Additionally, a ceramide signal was needed for PKR activation to be triggered by glucolipotoxicity and TNFα stimulation, and stabilization of P53 required endogenous ceramide accumulation. Glucolipotoxicity and pro-inflammatory cytokines therefore promote the sumoylation-dependent stability of P53 via the ceramide/PKR/Ubc9 signalling pathway that is involved in pancreatic β-cell proliferation inhibition in the development of type 2 diabetes.
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Affiliation(s)
- Ying Song
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, PR China
| | - XiaoMeng Wan
- Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing 210029, PR China
| | - LiLi Gao
- Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing 210029, PR China
| | - Yi Pan
- Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing 210029, PR China
| | - WeiPing Xie
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, PR China
| | - Hong Wang
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, PR China.
| | - Jun Guo
- Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing 210029, PR China
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21
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Seed Ahmed M, Ahmed MS, Pelletier J, Leumann H, Gu HF, Östenson CG. Expression of Protein Kinase C Isoforms in Pancreatic Islets and Liver of Male Goto-Kakizaki Rats, a Model of Type 2 Diabetes. PLoS One 2015; 10:e0135781. [PMID: 26398746 PMCID: PMC4580567 DOI: 10.1371/journal.pone.0135781] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 07/27/2015] [Indexed: 02/03/2023] Open
Abstract
Protein kinase C (PKC) is a family of protein kinases controlling protein phosphorylation and playing important roles in the regulation of metabolism. We have investigated expression levels of PKC isoforms in pancreatic islets and liver of diabetic Goto-Kakizaki (GK) rats with and without insulin treatment to evaluate their association with glucose homeostasis. mRNA and protein expression levels of PKC isoforms were assessed in pancreatic islets and liver of Wistar rats and GK rats with or without insulin treatment. PKCα and PKCζ mRNA expressions were down-regulated in islets of GK compared with Wistar rats. PKCα and phosphorylated PKCα (p-PKCα) protein expressions were decreased in islets of GK compared with insulin-treated GK and Wistar rats. PKCζ protein expression in islets was reduced in GK and insulin-treated GK compared with Wistar rats, but p-PKCζ was decreased only in GK rats. Islet PKCε mRNA and protein expressions were lower in GK compared with insulin-treated GK and Wistar rats. In liver, PKCδ and PKCζ mRNA expressions were decreased in both GK and insulin-treated GK compared with Wistar rats. Hepatic PKCζ protein expression was diminished in both GK rats with and without insulin treatment compared with Wistar rats. Hepatic PKCε mRNA expression was down-regulated in insulin-treated GK compared with GK and Wistar rats. PKCα, PKCε, and p-PKCζ expressions were secondary to hyperglycaemia in GK rat islets. Hepatic PKCδ and PKCζ mRNA expressions were primarily linked to hyperglycaemia. Additionally, hepatic PKCε mRNA expression could be under control of insulin.
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Affiliation(s)
- Mohammed Seed Ahmed
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Solna, Stockholm, Sweden; Department of Physiology, Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | | | - Julien Pelletier
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Solna, Stockholm, Sweden
| | - Hannes Leumann
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Solna, Stockholm, Sweden
| | - Harvest F Gu
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Solna, Stockholm, Sweden
| | - Claes-Göran Östenson
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Karolinska University Hospital, Solna, Stockholm, Sweden
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22
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Ye L, Robertson MA, Hesselson D, Stainier DYR, Anderson RM. Glucagon is essential for alpha cell transdifferentiation and beta cell neogenesis. Development 2015; 142:1407-17. [PMID: 25852199 DOI: 10.1242/dev.117911] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The interconversion of cell lineages via transdifferentiation is an adaptive mode of tissue regeneration and an appealing therapeutic target. However, its clinical exploitation is contingent upon the discovery of contextual regulators of cell fate acquisition and maintenance. In murine models of diabetes, glucagon-secreting alpha cells transdifferentiate into insulin-secreting beta cells following targeted beta cell depletion, regenerating the form and function of the pancreatic islet. However, the molecular triggers of this mode of regeneration are unknown. Here, using lineage-tracing assays in a transgenic zebrafish model of beta cell ablation, we demonstrate conserved plasticity of alpha cells during islet regeneration. In addition, we show that glucagon expression is upregulated after injury. Through gene knockdown and rescue approaches, we also find that peptides derived from the glucagon gene are necessary for alpha-to-beta cell fate switching. Importantly, whereas beta cell neogenesis was stimulated by glucose, alpha-to-beta cell conversion was not, suggesting that transdifferentiation is not mediated by glucagon/GLP-1 control of hepatic glucose production. Overall, this study supports the hypothesis that alpha cells are an endogenous reservoir of potential new beta cells. It further reveals that glucagon plays an important role in maintaining endocrine cell homeostasis through feedback mechanisms that govern cell fate stability.
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Affiliation(s)
- Lihua Ye
- Wells Center for Pediatric Research and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, 635 Barnhill Drive, Van Nuys Medical Sciences Building MS2053, Indianapolis, IN 46202, USA
| | - Morgan A Robertson
- Wells Center for Pediatric Research and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, 635 Barnhill Drive, Van Nuys Medical Sciences Building MS2053, Indianapolis, IN 46202, USA
| | - Daniel Hesselson
- Department of Biochemistry and Biophysics, 1550 4th Street Rock Hall Room 381, University of California San Francisco, San Francisco, CA 94143, USA
| | - Didier Y R Stainier
- Department of Biochemistry and Biophysics, 1550 4th Street Rock Hall Room 381, University of California San Francisco, San Francisco, CA 94143, USA
| | - Ryan M Anderson
- Wells Center for Pediatric Research and Department of Cellular and Integrative Physiology, Indiana University School of Medicine, 635 Barnhill Drive, Van Nuys Medical Sciences Building MS2053, Indianapolis, IN 46202, USA
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23
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Abu-Farha M, Abubaker J, Al-Khairi I, Cherian P, Noronha F, Hu FB, Behbehani K, Elkum N. Higher plasma betatrophin/ANGPTL8 level in Type 2 Diabetes subjects does not correlate with blood glucose or insulin resistance. Sci Rep 2015; 5:10949. [PMID: 26077345 PMCID: PMC4650613 DOI: 10.1038/srep10949] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 05/11/2015] [Indexed: 01/08/2023] Open
Abstract
Betatrophin/ANGPTL8 is a newly identified hormone produced in liver and adipose tissue that has been shown to be induced as a result of insulin resistance and regulates lipid metabolism. Little is known about betatrophin level in humans and its association with T2D and metabolic risk factors. Plasma level of betatrophin was measured by ELISA in 1603 subjects: 1047 non-diabetic and 556 T2D subjects and its associations with metabolic risk factors in both non-diabetic and T2D were also studied. Our data show a significant difference in betatrophin levels between non-diabetic (731.3 (59.5–10625.0) pg/ml) and T2D (1710.5 (197.4–12361.1) p < 0.001. Betatrophin was positively correlated with age, BMI, waist/hip ratio, FBG, HbA1C, HOMA-IR and TG in the non-diabetic subjects. However, no association was observed with BMI, FBG, HbA1C or HOMA-IR in T2D subjects. TC and LDL showed negative association with betatrophin in T2D subjects. Multivariate analysis showed that subjects in the highest tertile of betatrophin had higher odds of having T2D (odd ratio [OR] = 6.15, 95% confidence interval [CI] = (3.15 – 12.01). Our data show strong positive associations between betatrophin and FBG and insulin resistance in non-diabetic subjects. However, correlations with FBG and insulin resistance were diminished in T2D subjects.
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Affiliation(s)
| | | | | | | | - Fiona Noronha
- Biostatistics and Epidemiology Department Dasman Diabetes Institute, Kuwait City, Kuwait
| | - Frank B Hu
- Departments of Nutrition and Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Kazem Behbehani
- 1] Biochemistry and Molecular Biology Unit [2] Biostatistics and Epidemiology Department Dasman Diabetes Institute, Kuwait City, Kuwait
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24
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An L, Wang Y, Wang C, Fan M, Han X, Xu G, Yuan G, Li H, Sheng Y, Wang M, Sun J, Zhan J, Sun H, Li N, Ding F, Du P. Protective effect of Schisandrae chinensis oil on pancreatic β-cells in diabetic rats. Endocrine 2015; 48:818-25. [PMID: 25151401 DOI: 10.1007/s12020-014-0375-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 07/29/2014] [Indexed: 01/10/2023]
Abstract
Islet cell dysfunction in type 2 diabetes is primarily attributed to increased apoptosis of pancreatic β-Cells. The aim of the present study was to investigate the effects of Schisandrae chinensis oil on pancreatic β-Cells in type 2 diabetes mellitus rats and the associated molecular mechanisms of action. Wistar rats were randomly divided into diabetic rats and control rats, diabetic rats treated with Schisandrae chinensis oil (1 mg/kg), and control rats treated with Schisandrae chinensis oil. The serum fasting blood glucose, insulin, total cholesterol, and triglyceride levels along with MDA content, SOD and CAT activities in pancreatic tissues were measured. TUNEL was used to observe the apoptosis of rat pancreatic cells. Western blot was used to determine specific protein expression. The results showed that the oil significantly decreased fasting blood glucose, total cholesterol, triglyceride levels as well as the pancreatic MDA, but increased SOD and CAT activities. The protein expression of Bcl-2, PDX-1, GLUT-2, and GCK but not caspase 3 was significantly enhanced in the oil-treated rats compared with diabetic rats. However, Bax content was not significantly different between the control and DM groups. Schisandra chinensis oil improves pancreatic β-cell function by enhancing antioxidant potential of the pancreas, upregulating the expression of anti-apoptotic genes, increasing expression of glucose metabolism, and delaying islet cell apoptosis.
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Affiliation(s)
- Liping An
- College of Pharmacy, Beihua University, Jilin, 132013, Jilin, People's Republic of China
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Kaiser D, Oetjen E. Something old, something new and something very old: drugs for treating type 2 diabetes. Br J Pharmacol 2015; 171:2940-50. [PMID: 24641580 DOI: 10.1111/bph.12624] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 01/13/2014] [Accepted: 01/30/2014] [Indexed: 12/28/2022] Open
Abstract
Diabetes mellitus belongs to the most rapidly increasing diseases worldwide. Approximately 90-95% of these patients suffer from type 2 diabetes mellitus, which is characterized by peripheral insulin resistance and the progressive loss of beta-cell function and mass. Considering the complications of this chronic disease, a reliable anti-diabetic treatment is indispensable. An ideal oral anti-diabetic drug should not only correct glucose homeostasis but also preserve or even augment beta-cell function and mass, ameliorate the subclinical inflammation present under insulin-resistant conditions and prevent the macro- and microvascular consequences of diabetes in order to reduce the mortality. Despite the many anti-diabetic drugs already in use, there is an ongoing research for additional drugs, guided by different concepts of the pathogenesis of type 2 diabetes. This review will briefly summarize current oral anti-diabetic drugs. In addition, emerging strategies for the treatment of diabetes will be described, among them the inhibition of glucagon action and anti-inflammatory drugs. Their suitability as 'ideal anti-diabetic drugs' will be discussed.
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Affiliation(s)
- D Kaiser
- Department of Clinical Pharmacology and Toxicology, Cardiovascular Research Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Berná G, Oliveras-López MJ, Jurado-Ruíz E, Tejedo J, Bedoya F, Soria B, Martín F. Nutrigenetics and nutrigenomics insights into diabetes etiopathogenesis. Nutrients 2014; 6:5338-69. [PMID: 25421534 PMCID: PMC4245593 DOI: 10.3390/nu6115338] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 10/17/2014] [Accepted: 11/04/2014] [Indexed: 01/17/2023] Open
Abstract
Diabetes mellitus (DM) is considered a global pandemic, and the incidence of DM continues to grow worldwide. Nutrients and dietary patterns are central issues in the prevention, development and treatment of this disease. The pathogenesis of DM is not completely understood, but nutrient-gene interactions at different levels, genetic predisposition and dietary factors appear to be involved. Nutritional genomics studies generally focus on dietary patterns according to genetic variations, the role of gene-nutrient interactions, gene-diet-phenotype interactions and epigenetic modifications caused by nutrients; these studies will facilitate an understanding of the early molecular events that occur in DM and will contribute to the identification of better biomarkers and diagnostics tools. In particular, this approach will help to develop tailored diets that maximize the use of nutrients and other functional ingredients present in food, which will aid in the prevention and delay of DM and its complications. This review discusses the current state of nutrigenetics, nutrigenomics and epigenomics research on DM. Here, we provide an overview of the role of gene variants and nutrient interactions, the importance of nutrients and dietary patterns on gene expression, how epigenetic changes and micro RNAs (miRNAs) can alter cellular signaling in response to nutrients and the dietary interventions that may help to prevent the onset of DM.
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Affiliation(s)
- Genoveva Berná
- Department of Stem Cells, Andalusian Center of Molecular Biology and Regenerative Medicine, University Pablo Olavide (CABIMER-UPO), Seville 41091, Spain.
| | - María Jesús Oliveras-López
- Department of Stem Cells, Andalusian Center of Molecular Biology and Regenerative Medicine, University Pablo Olavide (CABIMER-UPO), Seville 41091, Spain.
| | - Enrique Jurado-Ruíz
- Department of Stem Cells, Andalusian Center of Molecular Biology and Regenerative Medicine, University Pablo Olavide (CABIMER-UPO), Seville 41091, Spain.
| | - Juan Tejedo
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), CIBER of Diabetes and Associated Metabolic Diseases, Instituto de Salud Carlos III, Madrid 28029, Spain.
| | - Francisco Bedoya
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), CIBER of Diabetes and Associated Metabolic Diseases, Instituto de Salud Carlos III, Madrid 28029, Spain.
| | - Bernat Soria
- Department of Stem Cells, Andalusian Center of Molecular Biology and Regenerative Medicine, University Pablo Olavide (CABIMER-UPO), Seville 41091, Spain.
| | - Franz Martín
- Department of Stem Cells, Andalusian Center of Molecular Biology and Regenerative Medicine, University Pablo Olavide (CABIMER-UPO), Seville 41091, Spain.
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Szkudelski T, Szkudelska K. Resveratrol and diabetes: from animal to human studies. Biochim Biophys Acta Mol Basis Dis 2014; 1852:1145-54. [PMID: 25445538 DOI: 10.1016/j.bbadis.2014.10.013] [Citation(s) in RCA: 230] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Revised: 10/10/2014] [Accepted: 10/20/2014] [Indexed: 02/07/2023]
Abstract
Diabetes mellitus is a serious disease affecting about 5% of people worldwide. Diabetes is characterized by hyperglycemia and impairment in insulin secretion and/or action. Moreover, diabetes is associated with metabolic abnormalities and serious complications. Resveratrol is a natural, biologically active polyphenol present in different plant species and known to have numerous health-promoting effects in both animals and humans. Anti-diabetic action of resveratrol has been extensively studied in animal models and in diabetic humans. In animals with experimental diabetes, resveratrol has been demonstrated to induce beneficial effects that ameliorate diabetes. Resveratrol, among others, improves glucose homeostasis, decreases insulin resistance, protects pancreatic β-cells, improves insulin secretion and ameliorates metabolic disorders. Effects induced by resveratrol are strongly related to the capability of this compound to increase expression/activity of AMPK and SIRT1 in various tissues of diabetic subjects. Moreover, anti-oxidant and anti-inflammatory effects of resveratrol were shown to be also involved in its action in diabetic animals. Preliminary clinical trials show that resveratrol is also effective in type 2 diabetic patients. Resveratrol may, among others, improve glycemic control and decrease insulin resistance. These results show that resveratrol holds great potential to treat diabetes and would be useful to support conventional therapy. This article is part of a Special Issue entitled: Resveratrol: Challenges in translating pre-clincial findigns to improved patient outcomes.
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Affiliation(s)
- Tomasz Szkudelski
- Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Wolynska 35, 60-637 Poznan, Poland.
| | - Katarzyna Szkudelska
- Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Wolynska 35, 60-637 Poznan, Poland
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Peplow PV, Baxter GD. Defining a therapeutic window for laser irradiation (810 nm) applied to the inguinal region to ameliorate diabetes in diabetic mice. Photomed Laser Surg 2014; 32:500-4. [PMID: 25102241 DOI: 10.1089/pho.2014.3745] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE The purpose of this study was to determine a therapeutic window of antidiabetic effect by laser irradiating the left inguinal region of diabetic mice (810 nm 20.4 and 40.8 J/cm(2)) for 7 days. BACKGROUND DATA Irradiation of 810 nm 10.2 J/cm(2) to the left inguinal region of diabetic mice for 7 days significantly decreased blood plasma fructosamine compared with nonirradiated controls. METHODS Forty-seven diabetic mice were used. Body weight and water intake of the mice were measured daily for 7 days prior to start of treatment (day 0). Mice were irradiated on the left inguinal region with 810 nm laser 20.4 J/cm(2) (n=15) or 40.8 J/cm(2) (n=15) for 7 days, or were not irradiated (control, n=17). Body weight and water intake were measured to day 7. On day 7, mice were fasted for 5 h, anesthetized with sodium pentobarbitone (i.p.), and blood plasma was collected. The blood plasma was assayed for glucose and fructosamine. RESULTS Water intake was significantly increased on day 7 compared with day 0 for diabetic mice receiving laser treatment. Blood plasma glucose levels on day 7 for diabetic mice irradiated 20.4 and 40.8 J/cm(2) were not significantly different than for nonirradiated controls. The blood plasma fructosamine level of diabetic mice irradiated with 20.4 J/cm(2) was significantly lower than for nonirradiated controls, whereas that for diabetic mice irradiated with 40.8 J/cm(2) was not significantly different than for nonirradiated controls. CONCLUSIONS Irradiation (810 nm laser 10.2-20.4 J/cm(2)) to the left inguinal region of diabetic mice for 7 days has the potential to ameliorate diabetes, as is shown by decreased blood plasma fructosamine.
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Guo JH, Chen H, Ruan YC, Zhang XL, Zhang XH, Fok KL, Tsang LL, Yu MK, Huang WQ, Sun X, Chung YW, Jiang X, Sohma Y, Chan HC. Glucose-induced electrical activities and insulin secretion in pancreatic islet β-cells are modulated by CFTR. Nat Commun 2014; 5:4420. [PMID: 25025956 PMCID: PMC4104438 DOI: 10.1038/ncomms5420] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Accepted: 06/17/2014] [Indexed: 01/08/2023] Open
Abstract
The cause of insulin insufficiency remains unknown in many diabetic cases. Up to 50% adult patients with cystic fibrosis (CF), a disease caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR), develop CF-related diabetes (CFRD) with most patients exhibiting insulin insufficiency. Here we show that CFTR is a regulator of glucose-dependent electrical acitivities and insulin secretion in β-cells. We demonstrate that glucose elicited whole-cell currents, membrane depolarization, electrical bursts or action potentials, Ca(2+) oscillations and insulin secretion are abolished or reduced by inhibitors or knockdown of CFTR in primary mouse β-cells or RINm5F β-cell line, or significantly attenuated in CFTR mutant (DF508) mice compared with wild-type mice. VX-809, a newly discovered corrector of DF508 mutation, successfully rescues the defects in DF508 β-cells. Our results reveal a role of CFTR in glucose-induced electrical activities and insulin secretion in β-cells, shed light on the pathogenesis of CFRD and possibly other idiopathic diabetes, and present a potential treatment strategy.
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Affiliation(s)
- Jing Hui Guo
- Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Hui Chen
- Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Ye Chun Ruan
- 1] Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China [2] Sichuan University-The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, Key Laboratory of Obstetric, Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education of China, West China Second University Hospital, Sichuan University, Chengdu 610041, China [3] Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Xue Lian Zhang
- Department of Endocrinology, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
| | - Xiao Hu Zhang
- Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Kin Lam Fok
- Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Lai Ling Tsang
- Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Mei Kuen Yu
- Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Wen Qing Huang
- Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Xiao Sun
- Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Yiu Wa Chung
- Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Xiaohua Jiang
- 1] Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China [2] Sichuan University-The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, Key Laboratory of Obstetric, Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education of China, West China Second University Hospital, Sichuan University, Chengdu 610041, China [3] Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Yoshiro Sohma
- Department of Pharmacology, Keio University School of Medicine, Shinjuku, Tokyo 160-8582, Japan
| | - Hsiao Chang Chan
- 1] Epithelial Cell Biology Research Center, Key Laboratory of Regenerative Medicine of Ministry of Education of China, CUHK-SJTU Joint Center for Human Reproduction and Related Disease, Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China [2] Sichuan University-The Chinese University of Hong Kong Joint Laboratory for Reproductive Medicine, Key Laboratory of Obstetric, Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education of China, West China Second University Hospital, Sichuan University, Chengdu 610041, China [3] Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
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García-Arevalo M, Alonso-Magdalena P, Rebelo Dos Santos J, Quesada I, Carneiro EM, Nadal A. Exposure to bisphenol-A during pregnancy partially mimics the effects of a high-fat diet altering glucose homeostasis and gene expression in adult male mice. PLoS One 2014; 9:e100214. [PMID: 24959901 PMCID: PMC4069068 DOI: 10.1371/journal.pone.0100214] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 05/22/2014] [Indexed: 12/17/2022] Open
Abstract
Bisphenol-A (BPA) is one of the most widespread EDCs used as a base compound in the manufacture of polycarbonate plastics. The aim of our research has been to study how the exposure to BPA during pregnancy affects weight, glucose homeostasis, pancreatic β-cell function and gene expression in the major peripheral organs that control energy flux: white adipose tissue (WAT), the liver and skeletal muscle, in male offspring 17 and 28 weeks old. Pregnant mice were treated with a subcutaneous injection of 10 µg/kg/day of BPA or a vehicle from day 9 to 16 of pregnancy. One month old offspring were divided into four different groups: vehicle treated mice that ate a normal chow diet (Control group); BPA treated mice that also ate a normal chow diet (BPA); vehicle treated animals that had a high fat diet (HFD) and BPA treated animals that were fed HFD (HFD-BPA). The BPA group started to gain weight at 18 weeks old and caught up to the HFD group before week 28. The BPA group as well as the HFD and HFD-BPA ones presented fasting hyperglycemia, glucose intolerance and high levels of non-esterified fatty acids (NEFA) in plasma compared with the Control one. Glucose stimulated insulin release was disrupted, particularly in the HFD-BPA group. In WAT, the mRNA expression of the genes involved in fatty acid metabolism, Srebpc1, Pparα and Cpt1β was decreased by BPA to the same extent as with the HFD treatment. BPA treatment upregulated Pparγ and Prkaa1 genes in the liver; yet it diminished the expression of Cd36. Hepatic triglyceride levels were increased in all groups compared to control. In conclusion, male offspring from BPA-treated mothers presented symptoms of diabesity. This term refers to a form of diabetes which typically develops in later life and is associated with obesity.
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Affiliation(s)
- Marta García-Arevalo
- Instituto de Bioingeniería, Universidad Miguel Hernández de Elche, Elche, Spain
- Centro de Investigación Biomédica En Red de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Universidad Miguel Hernández de Elche, Elche, Spain
| | - Paloma Alonso-Magdalena
- Departamento de Biología Aplicada, Universidad Miguel Hernández de Elche, Elche, Spain
- Centro de Investigación Biomédica En Red de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Universidad Miguel Hernández de Elche, Elche, Spain
| | - Junia Rebelo Dos Santos
- Instituto de Bioingeniería, Universidad Miguel Hernández de Elche, Elche, Spain
- Departamento de Biologia Estructural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, UNICAMP, Campinas, Brazil
| | - Ivan Quesada
- Instituto de Bioingeniería, Universidad Miguel Hernández de Elche, Elche, Spain
- Departamento de Biología Aplicada, Universidad Miguel Hernández de Elche, Elche, Spain
- Centro de Investigación Biomédica En Red de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Universidad Miguel Hernández de Elche, Elche, Spain
| | - Everardo M. Carneiro
- Departamento de Biologia Estructural e Funcional, Instituto de Biologia, Universidade Estadual de Campinas, UNICAMP, Campinas, Brazil
| | - Angel Nadal
- Instituto de Bioingeniería, Universidad Miguel Hernández de Elche, Elche, Spain
- Centro de Investigación Biomédica En Red de Diabetes y Enfermedades Metabólicas Asociadas, CIBERDEM, Universidad Miguel Hernández de Elche, Elche, Spain
- * E-mail:
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Metformin attenuates palmitate-induced endoplasmic reticulum stress, serine phosphorylation of IRS-1 and apoptosis in rat insulinoma cells. PLoS One 2014; 9:e97868. [PMID: 24896641 PMCID: PMC4045581 DOI: 10.1371/journal.pone.0097868] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 04/25/2014] [Indexed: 12/25/2022] Open
Abstract
Lipotoxicity refers to cellular dysfunctions caused by elevated free fatty acid levels playing a central role in the development and progression of obesity related diseases. Saturated fatty acids cause insulin resistance and reduce insulin production in the pancreatic islets, thereby generating a vicious cycle, which potentially culminates in type 2 diabetes. The underlying endoplasmic reticulum (ER) stress response can lead to even β-cell death (lipoapoptosis). Since improvement of β-cell viability is a promising anti-diabetic strategy, the protective effect of metformin, a known insulin sensitizer was studied in rat insulinoma cells. Assessment of palmitate-induced lipoapoptosis by fluorescent microscopy and by detection of caspase-3 showed a significant decrease in metformin treated cells. Attenuation of β-cell lipotoxicity was also revealed by lower induction/activation of various ER stress markers, e.g. phosphorylation of eukaryotic initiation factor 2α (eIF2α), c-Jun N-terminal kinase (JNK), insulin receptor substrate-1 (IRS-1) and induction of CCAAT/enhancer binding protein homologous protein (CHOP). Our results indicate that the β-cell protective activity of metformin in lipotoxicity can be at least partly attributed to suppression of ER stress.
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Nojiri T, Kurano M, Tokuhara Y, Ohkubo S, Hara M, Ikeda H, Tsukamoto K, Yatomi Y. Modulation of sphingosine-1-phosphate and apolipoprotein M levels in the plasma, liver and kidneys in streptozotocin-induced diabetic mice. J Diabetes Investig 2014; 5:639-48. [PMID: 25422763 PMCID: PMC4234226 DOI: 10.1111/jdi.12232] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 02/24/2014] [Accepted: 03/16/2014] [Indexed: 12/19/2022] Open
Abstract
AIMS/INTRODUCTION Sphingosine-1-phosphate (S1P), a multifunctional bioactive lipid mediator, is involved in various diseases. Apolipoprotein M (ApoM) carries S1P on high-density lipoprotein and modulates S1P metabolism to increase the total S1P mass in the body. Both S1P and ApoM are involved in diabetes. MATERIALS AND METHODS The present study examined the modulation of S1P and ApoM levels in the plasma, liver and kidneys in streptozotocin-induced diabetes (STZ) mice, and the effects of insulin on the S1P and ApoM levels in the plasma and liver in STZ mice and normal mice. We also examined the effects of insulin and glucose on the ApoM levels in HepG2 cells. RESULTS In STZ mice, both the plasma S1P and ApoM levels were higher than those in control mice. The hepatic S1P and ApoM contents were also elevated. The hepatic S1P and ApoM contents were reduced by insulin treatment, whereas high-dose insulin decreased the plasma S1P and ApoM levels. In mice without streptozotocin treatment, the administration of insulin decreased the plasma S1P and ApoM levels, and the hepatic content of ApoM, whereas the hepatic level of S1P was not altered. Treatment with insulin and incubation under a low glucose level decreased the ApoM levels in HepG2 cells. Regarding the kidney, the renal levels of S1P and ApoM were increased in STZ mice, and insulin treatment partially restored this increment. CONCLUSIONS In STZ mice, the levels of S1P and ApoM in the plasma, liver, and kidneys were increased. Insulin treatment somehow reversed this modulation in STZ mice.
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Affiliation(s)
- Takahiro Nojiri
- Department of Clinical Laboratory, The University of Tokyo Hospital Tokyo, Japan
| | - Makoto Kurano
- Department of Clinical Laboratory Medicine, Graduate School of Medicine, The University of Tokyo Tokyo, Japan
| | - Yasunori Tokuhara
- Department of Clinical Laboratory, The University of Tokyo Hospital Tokyo, Japan ; The Group of Neurobiology, Division of Health Sciences, Graduate School of Medicine, Osaka University Osaka, Japan
| | - Shigeo Ohkubo
- Department of Clinical Laboratory, The University of Tokyo Hospital Tokyo, Japan
| | - Masumi Hara
- Department of Medicine IV, Mizonokuchi Hospital, Teikyo University School of Medicine Kawasaki, Japan
| | - Hitoshi Ikeda
- Department of Clinical Laboratory, The University of Tokyo Hospital Tokyo, Japan ; Department of Clinical Laboratory Medicine, Graduate School of Medicine, The University of Tokyo Tokyo, Japan
| | - Kazuhisa Tsukamoto
- Department of Metabolism, Diabetes and Nephrology, Aizu Medical Center, Fukushima Medical University Fukushima, Japan
| | - Yutaka Yatomi
- Department of Clinical Laboratory, The University of Tokyo Hospital Tokyo, Japan ; Department of Clinical Laboratory Medicine, Graduate School of Medicine, The University of Tokyo Tokyo, Japan
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Kihira Y, Miyake M, Hirata M, Hoshina Y, Kato K, Shirakawa H, Sakaue H, Yamano N, Izawa-Ishizawa Y, Ishizawa K, Ikeda Y, Tsuchiya K, Tamaki T, Tomita S. Deletion of hypoxia-inducible factor-1α in adipocytes enhances glucagon-like peptide-1 secretion and reduces adipose tissue inflammation. PLoS One 2014; 9:e93856. [PMID: 24705496 PMCID: PMC3976326 DOI: 10.1371/journal.pone.0093856] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Accepted: 03/08/2014] [Indexed: 01/14/2023] Open
Abstract
It is known that obese adipose tissues are hypoxic and express hypoxia-inducible factor (HIF)-1α. Although some studies have shown that the expression of HIF-1α in adipocytes induces glucose intolerance, the mechanisms are still not clear. In this study, we examined its effects on the development of type 2 diabetes by using adipocyte-specific HIF-1α knockout (ahKO) mice. ahKO mice showed improved glucose tolerance compared with wild type (WT) mice. Macrophage infiltration and mRNA levels of monocyte chemotactic protein-1 (MCP-1) and tumor necrosis factor α (TNFα) were decreased in the epididymal adipose tissues of high fat diet induced obese ahKO mice. The results indicated that the obesity-induced adipose tissue inflammation was suppressed in ahKO mice. In addition, in the ahKO mice, serum insulin levels were increased under the free-feeding but not the fasting condition, indicating that postprandial insulin secretion was enhanced. Serum glucagon-like peptide-1 (GLP-1) levels were also increased in the ahKO mice. Interestingly, adiponectin, whose serum levels were increased in the obese ahKO mice compared with the obese WT mice, stimulated GLP-1 secretion from cultured intestinal L cells. Therefore, insulin secretion may have been enhanced through the adiponectin-GLP-1 pathway in the ahKO mice. Our results suggest that the deletion of HIF-1α in adipocytes improves glucose tolerance by enhancing insulin secretion through the GLP-1 pathway and by reducing macrophage infiltration and inflammation in adipose tissue.
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Affiliation(s)
- Yoshitaka Kihira
- Department of Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Mariko Miyake
- Department of Medical Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Manami Hirata
- Department of Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
- Student Laboratory, Faculty of Medicine, The University of Tokushima, Tokushima, Japan
| | - Yoji Hoshina
- Department of Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
- Student Laboratory, Faculty of Medicine, The University of Tokushima, Tokushima, Japan
| | - Kana Kato
- Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, Miyagi, Japan
| | - Hitoshi Shirakawa
- Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, Miyagi, Japan
| | - Hiroshi Sakaue
- Department of Nutrition and Metabolism, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Noriko Yamano
- Department of Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Yuki Izawa-Ishizawa
- Department of Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Keisuke Ishizawa
- Department of Medical Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Yasumasa Ikeda
- Department of Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Koichiro Tsuchiya
- Department of Medical Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Toshiaki Tamaki
- Department of Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Shuhei Tomita
- Division of Molecular Pharmacology, Faculty of Medicine, Tottori University, Tottori, Japan
- * E-mail:
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Zhou J, Meng Y, Tian S, Chen J, Liu M, Zhuo M, Zhang Y, Du H, Wang X. Comparative microRNA expression profiles of cynomolgus monkeys, rat, and human reveal that mir-182 is involved in T2D pathogenic processes. J Diabetes Res 2014; 2014:760397. [PMID: 25530976 PMCID: PMC4235598 DOI: 10.1155/2014/760397] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 09/02/2014] [Accepted: 09/30/2014] [Indexed: 12/16/2022] Open
Abstract
Type 2 diabetes (T2D) is a prevalent disease that happens around the world and usually happens with insulin resistance. MicroRNAs (miRNAs) represented important roles in the suppression of gene expression and were proven to be related to human diseases. In this study, we used cynomolgus monkey fed with normal and high fatty diet (HFD), respectively, to analyze the miRNA expression profile in whole blood by deep sequencing. Finally in total 24 miRNAs with differential expression were filtered. Among them, miR-182 related to the insulin resistance by modulating FOXO1 and PI3K/AKT cascade and had the greatest copy number in the whole blood. Decrease of miR-182 in T2D cynomolgus individuals is completely consistent with the previous studies in human and rat. Integrating miR-182 tissue expression profile, target genes, and copy number in blood reveals that miR-182 plays a key role in crucial genes modulation, such as FOXO1 and BHLHE22, which leads to potential hyperglycemia and modulates the insulin secretion. In addition, miR-182 might regulate the processes of both cell proliferation and apoptosis that play crucial role in determining the cells' fate. Therefore, miR-182 can be a biomarker in diagnosis of the potential T2D that has benefits for medical purpose.
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Affiliation(s)
- Jinghui Zhou
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Yuhuan Meng
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Shuai Tian
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Junhui Chen
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Mingyu Liu
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Min Zhuo
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
| | - Yu Zhang
- Guangdong Key Laboratory of Laboratory Animals, Guangzhou 510663, China
| | - Hongli Du
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
- *Hongli Du:
| | - Xiaoning Wang
- School of Bioscience and Bioengineering, Guangdong Provincial Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou 510006, China
- Chinese PLA General Hospital, Beijing 100853, China
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Bernard C, Della Zuana O, Ktorza A. [Interaction between environment and genetic background in type 2 diabetes: lessons from animal models]. Med Sci (Paris) 2013; 29:791-9. [PMID: 24005636 DOI: 10.1051/medsci/2013298020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The respective roles of predisposing genetic factors and environmental factors in the development of type 2 diabetes (T2D) in obese subjects is poorly documented. Rodent models have been set up in an attempt to better understand of the differential effect of a prolonged metabolic stress induced by a high fat diet on glycaemic control according to the genetic background. In utero growth retardation resulting from a hypocaloric diet in pregnant rats induces a dramatic alteration of the development of islet cells leading to diabetes and insulin secretory defects in adult age. Experimentally induced diabetes in rodents results in hyperglycaemia and hyperinsulinemia in the fetus related to accelerated endocrine pancreas maturation responsible for the onset of diabetes in the adult. Deranged metabolic environment during fetal life may therefore further contribute to the onset of diabetes in the adult. Normal mouse strains with different genetic backgrounds show a wide range of responses to a high fat diet, with strains resistant to the diet and other more or less sensitive to the diet, the most sensitive exhibiting obesity diabetes and, insulin deficiency. The inability of the β cell to respond to the increased insulin demand related to insulin resistance seems to be pivotal in the pathophysiologic process and a new notion is emerging: "nutritional genetics" which studies the influence of nutrients on gene expression.
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Affiliation(s)
- Catherine Bernard
- Division de recherche sur les maladies métaboliques, Institut de recherches Servier, Suresnes, France.
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Botsikas D, Terraz S, Vinet L, Lamprianou S, Becker C, Bosco D, Meda P, Montet X. Pancreatic magnetic resonance imaging after manganese injection distinguishes type 2 diabetic and normoglycemic patients. Islets 2012; 4:243-8. [PMID: 22722479 PMCID: PMC3442822 DOI: 10.4161/isl.20857] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A non-invasive method to image the mass and/or function of human pancreatic islets is needed to monitor the progression of diabetes, and the effect of therapeutic interventions. As yet, no method is available for this purpose, which could be applied to in situ human islets. Animal and in vitro studies have documented that manganese infusion could improve the magnetic resonance imaging (MRI) of the endocrine pancreas. Here, we have tested whether a similar approach could discriminate diabetic and non-diabetic patients. In vitro, human isolated islets readily incorporated manganese. In vivo, 243 manganese-enhanced magnetic resonance imaging (MEMRI) examinations were reviewed, including 41 examinations which were run on 24 patients with type 2 diabetes and 202 examinations which were run on 119 normoglycemic patients. The results show that MEMRI discriminates type 2 diabetics from non-diabetic patients, based on the signal enhancement of pancreas.
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Affiliation(s)
- Diomidis Botsikas
- Department of Radiology; Geneva University Hospital; Geneva, Switzerland
| | - Sylvain Terraz
- Department of Radiology; Geneva University Hospital; Geneva, Switzerland
| | - Laurent Vinet
- Department of Cell Physiology and Metabolism; Geneva University; Geneva, Switzerland
| | - Smaragda Lamprianou
- Department of Cell Physiology and Metabolism; Geneva University; Geneva, Switzerland
| | - Christoph Becker
- Department of Radiology; Geneva University Hospital; Geneva, Switzerland
| | - Domenico Bosco
- Department of Surgery; Geneva University Hospital; Geneva, Switzerland
| | - Paolo Meda
- Department of Cell Physiology and Metabolism; Geneva University; Geneva, Switzerland
| | - Xavier Montet
- Department of Radiology; Geneva University Hospital; Geneva, Switzerland
- Correspondence to: Xavier Montet,
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