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Dong DY, Li PY, Wang YF, Wang P, Wu YH, Gao SG, Li SQ. High glucose-increased miR-200c contributes to cellular senescence and DNA damage in neural stem cells. Birth Defects Res 2023; 115:1770-1779. [PMID: 37776548 DOI: 10.1002/bdr2.2254] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 09/16/2023] [Accepted: 09/19/2023] [Indexed: 10/02/2023]
Abstract
BACKGROUND Maternal diabetes increases the risk for neural tube defects (NTDs). It is unclear if miRNAs, senescence, and DNA damage are involved in this process. In this study, we used neural stem cells as an in vitro proxy of embryonic neuroepithelium to investigate whether high glucose triggers neural stem cell senescence and DNA damage by upregulating miR-200c, which may be responsible for NTDs. METHODS C17.2 neural stem cells were cultured with normal glucose (5 mM) or high glucose (≥16.7 mM) at different doses and time points for detecting miR-200c levels, markers of senescence and DNA damage. Neural stem cells were exposed to antioxidant SOD1 mimetic Tempol and high glucose for 48 h to test roles of oxidative stress on the miR-200c, senescence, and DNA damage levels. An miR-200c mimic and an inhibitor were transfected into neural stem cells to increase or decrease miR-200c activities. RESULTS High glucose upregulated miR-200c in neural stem cells. A time course study of the effect of high glucose revealed that miR-200c initially increased at 12 h and reached its zenith at 18 h. Tempol reduced miR-200c levels caused by high glucose. High glucose induced markers of senescence and DNA damage in neural stem cells. Tempol abolished high glucose-induced markers of senescence and DNA damage. The miR-200c inhibitor suppressed high glucose-induced markers of senescence and DNA damage. Treatment with miR-200c mimic imitates high glucose-induced markers of senescence and DNA damage. CONCLUSIONS We show that high glucose increases miR-200c, which contributes to cellular senescence and DNA damage in neural stem cells and provides a potential pathway for maternal diabetes-induced neural tube defects.
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Affiliation(s)
- Dao-Yin Dong
- Department of Public Health, School of Basic Medical Sciences, Henan University of Science and Technology, Luoyang, China
| | - Pu-Yu Li
- Department of General Medicine, The First Affiliated Hospital of Henan University of Science and Technology, Luoyang, China
| | - Ying-Fang Wang
- Department of Public Health, School of Basic Medical Sciences, Henan University of Science and Technology, Luoyang, China
| | - Ping Wang
- Department of Public Health, School of Basic Medical Sciences, Henan University of Science and Technology, Luoyang, China
| | - Yu-Han Wu
- Department of Public Health, School of Basic Medical Sciences, Henan University of Science and Technology, Luoyang, China
| | - She-Gan Gao
- Henan Key Laboratory of Cancer Epigenetics, The First Affiliated Hospital of Henan University of Science and Technology, Luoyang, China
| | - San-Qiang Li
- Henan Centre for Engineering and Technology Research on Prevention and Treatment of Liver Diseases, School of Basic Medical Sciences, Henan University of Science and Technology, Luoyang, China
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2
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Chen ACH, Huang W, Fong SW, Chan C, Lee KC, Yeung WSB, Lee YL. Hyperglycemia Altered DNA Methylation Status and Impaired Pancreatic Differentiation from Embryonic Stem Cells. Int J Mol Sci 2021; 22:ijms221910729. [PMID: 34639069 PMCID: PMC8509790 DOI: 10.3390/ijms221910729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/27/2021] [Accepted: 09/30/2021] [Indexed: 11/16/2022] Open
Abstract
The prevalence of type 2 diabetes (T2D) is rapidly increasing across the globe. Fetal exposure to maternal diabetes was correlated with higher prevalence of impaired glucose tolerance and T2D later in life. Previous studies showed aberrant DNA methylation patterns in pancreas of T2D patients. However, the underlying mechanisms remained largely unknown. We utilized human embryonic stem cells (hESC) as the in vitro model for studying the effects of hyperglycemia on DNA methylome and early pancreatic differentiation. Culture in hyperglycemic conditions disturbed the pancreatic lineage potential of hESC, leading to the downregulation of expression of pancreatic markers PDX1, NKX6-1 and NKX6-2 after in vitro differentiation. Genome-wide DNA methylome profiling revealed over 2000 differentially methylated CpG sites in hESC cultured in hyperglycemic condition when compared with those in control glucose condition. Gene ontology analysis also revealed that the hypermethylated genes were enriched in cell fate commitment. Among them, NKX6-2 was validated and its hypermethylation status was maintained upon differentiation into pancreatic progenitor cells. We also established mouse ESC lines at both physiological glucose level (PG-mESC) and conventional hyperglycemia glucose level (HG-mESC). Concordantly, DNA methylome analysis revealed the enrichment of hypermethylated genes related to cell differentiation in HG-mESC, including Nkx6-1. Our results suggested that hyperglycemia dysregulated the epigenome at early fetal development, possibly leading to impaired pancreatic development.
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Affiliation(s)
- Andy Chun Hang Chen
- Shenzhen Key Laboratory of Fertility Regulation, Reproductive Medicine Center, The University of Hong Kong, Shenzhen Hospital, Shenzhen 518000, China;
- Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong; (W.H.); (S.W.F.); (C.C.); (K.C.L.)
| | - Wen Huang
- Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong; (W.H.); (S.W.F.); (C.C.); (K.C.L.)
| | - Sze Wan Fong
- Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong; (W.H.); (S.W.F.); (C.C.); (K.C.L.)
| | - Chris Chan
- Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong; (W.H.); (S.W.F.); (C.C.); (K.C.L.)
| | - Kai Chuen Lee
- Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong; (W.H.); (S.W.F.); (C.C.); (K.C.L.)
| | - William Shu Biu Yeung
- Shenzhen Key Laboratory of Fertility Regulation, Reproductive Medicine Center, The University of Hong Kong, Shenzhen Hospital, Shenzhen 518000, China;
- Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong; (W.H.); (S.W.F.); (C.C.); (K.C.L.)
- Correspondence: (W.S.B.Y.); (Y.L.L.)
| | - Yin Lau Lee
- Shenzhen Key Laboratory of Fertility Regulation, Reproductive Medicine Center, The University of Hong Kong, Shenzhen Hospital, Shenzhen 518000, China;
- Department of Obstetrics and Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, 21 Sassoon Road, Hong Kong; (W.H.); (S.W.F.); (C.C.); (K.C.L.)
- Correspondence: (W.S.B.Y.); (Y.L.L.)
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3
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Jung JH, Loeken MR. Diabetic Embryopathy Susceptibility in Mice Is Associated with Differential Dependence on Glucosamine and Modulation of High Glucose-Induced Oxidative Stress. Antioxidants (Basel) 2021; 10:antiox10081156. [PMID: 34439404 PMCID: PMC8388881 DOI: 10.3390/antiox10081156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/15/2021] [Accepted: 07/18/2021] [Indexed: 11/16/2022] Open
Abstract
The high KM glucose transporter, GLUT2 (SLC2A2), is expressed by embryos and causes high rates of glucose transport during maternal hyperglycemic episodes in diabetic pregnancies and causes congenital malformations (diabetic embryopathy). GLUT2 is also a low KM transporter of the amino sugar, glucosamine (GlcN), which enters the hexosamine biosynthetic pathway (HBP) and provides substrate for glycosylation reactions. Exogenous GlcN also increases activity of the pentose phosphate pathway (PPP), which increases production of NADPH reducing equivalents. GLUT2-transported GlcN is inhibited by high glucose concentrations. Not all mouse strains are susceptible to diabetic embryopathy. The aim of this study was to test the hypothesis that susceptibility to diabetic embryopathy is related to differential dependence on exogenous GlcN for glycosylation or stimulation of the PPP. We tested this using murine embryonic stem cell (ESC) lines that were derived from embryopathy-susceptible FVB/NJ (FVB), and embryopathy-resistant C57Bl/6J (B6), embryos in the presence of low or high glucose, and in the presence or absence of GlcN. There were no significant differences in Glut2 expression, or of glucose or GlcN transport, between FVB and B6 ESC. GlcN effects on growth and incorporation into glycoproteins indicated that FVB ESC are more dependent on exogenous GlcN than are B6 ESC. GlcN stimulated PPP activity in FVB but not in B6 ESC. High glucose induced oxidative stress in FVB ESC but not in B6 ESC. These results indicate that FVB embryos are more dependent on exogenous GlcN for glycosylation, but also for stimulation of the PPP and NADPH production, than are B6 embryos, thereby rendering FVB embryos more susceptible to high glucose to induce oxidative stress.
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4
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Identification of new GLUT2-selective inhibitors through in silico ligand screening and validation in eukaryotic expression systems. Sci Rep 2021; 11:13751. [PMID: 34215797 PMCID: PMC8253845 DOI: 10.1038/s41598-021-93063-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 06/14/2021] [Indexed: 01/07/2023] Open
Abstract
Glucose is an essential energy source for cells. In humans, its passive diffusion through the cell membrane is facilitated by members of the glucose transporter family (GLUT, SLC2 gene family). GLUT2 transports both glucose and fructose with low affinity and plays a critical role in glucose sensing mechanisms. Alterations in the function or expression of GLUT2 are involved in the Fanconi-Bickel syndrome, diabetes, and cancer. Distinguishing GLUT2 transport in tissues where other GLUTs coexist is challenging due to the low affinity of GLUT2 for glucose and fructose and the scarcity of GLUT-specific modulators. By combining in silico ligand screening of an inward-facing conformation model of GLUT2 and glucose uptake assays in a hexose transporter-deficient yeast strain, in which the GLUT1-5 can be expressed individually, we identified eleven new GLUT2 inhibitors (IC50 ranging from 0.61 to 19.3 µM). Among them, nine were GLUT2-selective, one inhibited GLUT1-4 (pan-Class I GLUT inhibitor), and another inhibited GLUT5 only. All these inhibitors dock to the substrate cavity periphery, close to the large cytosolic loop connecting the two transporter halves, outside the substrate-binding site. The GLUT2 inhibitors described here have various applications; GLUT2-specific inhibitors can serve as tools to examine the pathophysiological role of GLUT2 relative to other GLUTs, the pan-Class I GLUT inhibitor can block glucose entry in cancer cells, and the GLUT2/GLUT5 inhibitor can reduce the intestinal absorption of fructose to combat the harmful effects of a high-fructose diet.
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5
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Schmidl S, Tamayo Rojas SA, Iancu CV, Choe JY, Oreb M. Functional Expression of the Human Glucose Transporters GLUT2 and GLUT3 in Yeast Offers Novel Screening Systems for GLUT-Targeting Drugs. Front Mol Biosci 2021; 7:598419. [PMID: 33681287 PMCID: PMC7930720 DOI: 10.3389/fmolb.2020.598419] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 12/23/2020] [Indexed: 01/31/2023] Open
Abstract
Human GLUT2 and GLUT3, members of the GLUT/SLC2 gene family, facilitate glucose transport in specific tissues. Their malfunction or misregulation is associated with serious diseases, including diabetes, metabolic syndrome, and cancer. Despite being promising drug targets, GLUTs have only a few specific inhibitors. To identify and characterize potential GLUT2 and GLUT3 ligands, we developed a whole-cell system based on a yeast strain deficient in hexose uptake, whose growth defect on glucose can be rescued by the functional expression of human transporters. The simplicity of handling yeast cells makes this platform convenient for screening potential GLUT2 and GLUT3 inhibitors in a growth-based manner, amenable to high-throughput approaches. Moreover, our expression system is less laborious for detailed kinetic characterization of inhibitors than alternative methods such as the preparation of proteoliposomes or uptake assays in Xenopus oocytes. We show that functional expression of GLUT2 in yeast requires the deletion of the extended extracellular loop connecting transmembrane domains TM1 and TM2, which appears to negatively affect the trafficking of the transporter in the heterologous expression system. Furthermore, single amino acid substitutions at specific positions of the transporter sequence appear to positively affect the functionality of both GLUT2 and GLUT3 in yeast. We show that these variants are sensitive to known inhibitors phloretin and quercetin, demonstrating the potential of our expression systems to significantly accelerate the discovery of compounds that modulate the hexose transport activity of GLUT2 and GLUT3.
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Affiliation(s)
- Sina Schmidl
- Institute of Molecular Biosciences, Faculty of Biological Sciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Sebastian A Tamayo Rojas
- Institute of Molecular Biosciences, Faculty of Biological Sciences, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Cristina V Iancu
- Department of Chemistry, East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States
| | - Jun-Yong Choe
- Department of Chemistry, East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC, United States.,Department of Biochemistry and Molecular Biology, The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL, United States
| | - Mislav Oreb
- Institute of Molecular Biosciences, Faculty of Biological Sciences, Goethe University Frankfurt, Frankfurt am Main, Germany
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Abstract
PURPOSE OF REVIEW Fetuses of diabetic mothers are at increased risk for congenital malformations. Research in recent decades using animal and embryonic stem cell models has revealed many embryonic developmental processes that are disturbed by maternal diabetes. The aim of this review is to give clinicians a better understanding of the reasons for rigorous glycemic control in early pregnancy, and to provide background to guide future research. RECENT FINDINGS Mouse models of diabetic pregnancy have revealed mechanisms for altered expression of tissue-specific genes that lead to malformations that are more common in diabetic pregnancies, such as neural tube defects (NTDs) and congenital heart defects (CHDs), and how altered gene expression causes apoptosis that leads to malformations. Embryos express the glucose transporter, GLUT2, which confers susceptibility to malformation, due to high rates of glucose uptake during maternal hyperglycemia and subsequent oxidative stress; however, the teleological function of GLUT2 for mammalian embryos may be to transport the amino sugar glucosamine (GlcN) from maternal circulation to be used as substrate for glycosylation reactions and to promote embryo cell growth. Malformations in diabetic pregnancy may be not only due to excess glucose uptake but also due to insufficient GlcN uptake. Avoiding maternal hyperglycemia during early pregnancy should prevent excess glucose uptake via GLUT2 into embryo cells, and also permit sufficient GLUT2-mediated GlcN uptake.
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Affiliation(s)
- Mary R Loeken
- Section on Islet Cell and Regenerative Biology, Department of Medicine, Joslin Diabetes Center and Harvard Medical School, One Joslin Place, Boston, MA, 02215, USA.
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7
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Perphenazine Attenuates the Pro-Inflammatory Responses in Mouse Models of Th2-Type Allergic Dermatitis. Int J Mol Sci 2020; 21:ijms21093241. [PMID: 32375285 PMCID: PMC7247351 DOI: 10.3390/ijms21093241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/28/2020] [Accepted: 05/01/2020] [Indexed: 12/31/2022] Open
Abstract
Developing dermatitis therapeutics has been faced with challenges including adverse effects of topical steroid and high cost of new developing drugs. Here, we found the expression levels of dopamine receptor D2 is higher in skin biopsies of dermatitis patients and an oxazolone-induced animal model of dermatitis. We used perphenazine, an FDA-approved dopamine receptor antagonist to determine the therapeutic effect. Two different animal models including 12-o-tetradecanoylphorbol-13-acetate (TPA) and oxazolone (OXA)-induced dermatitis were employed. TPA and OXA-mediated ear swelling was attenuated by perphenazine. Moreover, perphenazine inhibited infiltrated mast cells into lesion area. We found levels of serum IgE, histamine and cytokines are decreased in mice cotreated with perphenazine and OXA compared to OXA-treated mice. Overall, this is a first study showing that the FDA-approved, anti-psychotic drug, perphenazine, alleviates animal models of dermatitis.
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8
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Choi M, Choi YM, Choi SY, An IS, Bae S, An S, Jung JH. Glucose metabolism regulates expression of hair-inductive genes of dermal papilla spheres via histone acetylation. Sci Rep 2020; 10:4887. [PMID: 32184439 PMCID: PMC7078220 DOI: 10.1038/s41598-020-61824-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 03/02/2020] [Indexed: 12/15/2022] Open
Abstract
Cellular metabolism is one of the crucial factors to regulate epigenetic landscape in various cells including immune cells, embryonic stem cells and hair follicle stem cells. Dermal papilla cells (DP) interact with epithelial stem cells to orchestrate hair formation. Here we show that active DP exhibit robust aerobic glycolysis. We observed decrease of signature genes associated with hair induction by DP in presence of low glucose (2 mM) and glycolysis inhibitors. Moreover, hair shaft elongation was attenuated by glycolysis inhibitors. Interestingly, excessive glucose is able to increase the expression of hair inductive genes and elongation of hair shaft. We also observed glycolysis-mediated histone acetylation is increased and chemical inhibition of acetyltransferase reduces expression of the signature genes associated with hair induction in active DP. These results suggest that glucose metabolism is required for expression of signature genes associated with hair induction. This finding may be beneficial for establishing and maintaining of active DP to generate hair follicle in vitro.
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Affiliation(s)
- Mina Choi
- Research Institute for Molecular-Targeted Drugs, Department of Cosmetics Engineering, Konkuk University, Seoul, 05029, South Korea
| | - Yeong Min Choi
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea
| | - Soo-Young Choi
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea
| | - In-Sook An
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea
| | - Seunghee Bae
- Research Institute for Molecular-Targeted Drugs, Department of Cosmetics Engineering, Konkuk University, Seoul, 05029, South Korea
| | - Sungkwan An
- Research Institute for Molecular-Targeted Drugs, Department of Cosmetics Engineering, Konkuk University, Seoul, 05029, South Korea.
| | - Jin Hyuk Jung
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea.
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9
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Heo MJ, Lee C, Choi SY, Choi YM, An IS, Bae S, An S, Jung JH. Nintedanib ameliorates animal model of dermatitis. Sci Rep 2020; 10:4493. [PMID: 32161331 PMCID: PMC7066145 DOI: 10.1038/s41598-020-61424-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 02/20/2020] [Indexed: 02/06/2023] Open
Abstract
Nintedanib, a receptor tyrosine kinase (RTK) inhibitor has been developed as therapeutics for idiopathic pulmonary fibrosis and non-small lung cancer. We found that the expression levels of RTK, especially VEGFR1 is increased in skin biopsies of dermatitis patients from multiple independent datasets. Moreover, VEGFR1 is highly expressed by infiltrated cells in dermis from oxazolone (OXA) treated mice. Interestingly, nintedanib alleviates dermatitis symptom in OXA-induced animal model. Especially, levels of epidermis thickness, infiltrated immune cells including mast cells and eosinophils were decreased from mice cotreated with nintedanib and OXA compared with OXA treated mice. Moreover, serum IgE and Th2 cytokines including IL-4 and IL-13 were decreased by nintedanib treatment. These results suggest an evidence that nintedanib alleviates animal model of dermatitis.
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Affiliation(s)
- Min-Jeong Heo
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea
| | - Chanmi Lee
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea
| | - Soo Young Choi
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea
| | - Yeong Min Choi
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea
| | - In-Sook An
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea
| | - Seunghee Bae
- Research Institute for Molecular-Targeted Drugs, Department of Cosmetics Engineering, Konkuk University, Seoul, 05029, South Korea
| | - Sungkwan An
- Research Institute for Molecular-Targeted Drugs, Department of Cosmetics Engineering, Konkuk University, Seoul, 05029, South Korea.
| | - Jin Hyuk Jung
- Korea Institute of Dermatological Science, GeneCellPharm Corporation, 375 Munjeong 2(i)-dong, Songpa-gu, Seoul, 05836, South Korea.
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Abstract
Metformin has been prescribed in pregnancy for over 40 years; for much of this time, use has been limited both in numbers and geographically, and the evidence base has been confined to observational studies. In early years, perceived safety concerns and lack of availability of the drug in many countries acted as a barrier to use. More recently, RCTs have begun to examine the role of metformin in pregnancy in much-needed detail. However, this evidence base has been interpreted differently in different countries, leading to very wide variation in its current application in pregnancy. In this short review, we will discuss the history of metformin in pregnancy and highlight some of the key clinical trials. We will then consider some of the remaining controversies associated with metformin use in pregnancy, most important of these being the potential for long-term 'programming' effects on the fetus as a result of metformin being able to cross the placenta. We will also consider clinical situations where metformin might be avoided. Finally, we will discuss some future directions for this drug as it reaches its sixtieth anniversary.
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Affiliation(s)
- Robert S Lindsay
- Institute of Cardiovascular and Medical Sciences, British Heart Foundation (BHF) Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK.
| | - Mary R Loeken
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, MA, USA
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11
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Yang P, Chen X, Kaushal S, Reece EA, Yang P. High glucose suppresses embryonic stem cell differentiation into cardiomyocytes : High glucose inhibits ES cell cardiogenesis. Stem Cell Res Ther 2016; 7:187. [PMID: 27938398 PMCID: PMC5148851 DOI: 10.1186/s13287-016-0446-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 11/11/2016] [Accepted: 11/22/2016] [Indexed: 12/18/2022] Open
Abstract
Background Babies born to mothers with pregestational diabetes have a high risk for congenital heart defects (CHD). Embryonic stem cells (ESCs) are excellent in vitro models for studying the effect of high glucose on cardiac lineage specification because ESCs can be differentiated into cardiomyocytes. ESC maintenance and differentiation are currently performed under high glucose conditions, whose adverse effects have never been clarified. Method We investigated the effect of high glucose on cardiomyocyte differentiation from a well-characterized ESC line, E14, derived from mouse blastocysts. E14 cells maintained under high glucose (25 mM) failed to generate any beating cardiomyocytes using the hanging-drop embryonic body method. We created a glucose-responsive E14 cell line (GR-E14) through a graduated low glucose adaptation. The expression of stem cell markers was similar in the parent E14 cells and the GR-E14 cells. Results Glucose transporter 2 gene was increased in GR-E14 cells. When GR-E14 cells were differentiated into cardiomyocytes under low (5 mM) or high (25 mM) glucose conditions, high glucose significantly delayed the appearance and reduced the number of TNNT2 (Troponin T Type 2)-positive contracting cardiomyocytes. High glucose suppressed the expression of precardiac mesoderm markers, cardiac transcription factors, mature cardiomyocyte markers, and potassium channel proteins. High glucose impaired the functionality of ESC-derived cardiomyocytes by suppressing the frequencies of Ca2+ wave and contraction. Conclusions Our findings suggest that high glucose inhibits ESC cardiogenesis by suppressing key developmental genes essential for the cardiac program. Electronic supplementary material The online version of this article (doi:10.1186/s13287-016-0446-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Penghua Yang
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Maryland School of Medicine, BRB11-039, 655W. Baltimore Street, Baltimore, MD, 21201, USA
| | - Xi Chen
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Maryland School of Medicine, BRB11-039, 655W. Baltimore Street, Baltimore, MD, 21201, USA
| | - Sunjay Kaushal
- Division of Cardiac Surgery, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - E Albert Reece
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Maryland School of Medicine, BRB11-039, 655W. Baltimore Street, Baltimore, MD, 21201, USA.,Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Peixin Yang
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Maryland School of Medicine, BRB11-039, 655W. Baltimore Street, Baltimore, MD, 21201, USA. .,Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
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12
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Jung JH, Iwabuchi K, Yang Z, Loeken MR. Embryonic Stem Cell Proliferation Stimulated By Altered Anabolic Metabolism From Glucose Transporter 2-Transported Glucosamine. Sci Rep 2016; 6:28452. [PMID: 27311888 PMCID: PMC4911601 DOI: 10.1038/srep28452] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Accepted: 06/02/2016] [Indexed: 01/19/2023] Open
Abstract
The hexose transporter, GLUT2 (SLC2A2), which is expressed by mouse embryos, is important for survival before embryonic day 10.5, but its function in embryos is unknown. GLUT2 can transport the amino sugar glucosamine (GlcN), which could increase substrate for the hexosamine biosynthetic pathway (HBSP) that produces UDP-N-acetylglucosamine for O-linked N-acetylglucosamine modification (O-GlcNAcylation) of proteins. To understand this, we employed a novel murine embryonic stem cell (ESC) line that, like mouse embryos, expresses functional GLUT2 transporters. GlcN stimulated ESC proliferation in a GLUT2-dependent fashion but did not regulate pluripotency. Stimulation of proliferation was not due to increased O-GlcNAcylation. Instead, GlcN decreased dependence of the HBSP on fructose-6-PO4 and glutamine. Consequently, glycolytic- and glutamine-derived intermediates that are needed for anabolic metabolism were increased. Thus, maternally obtained GlcN may increase substrates for biomass accumulation by embryos, as exogenous GlcN does for GLUT2-expressing ESC, and may explain the need for GLUT2 expression by embryos.
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Affiliation(s)
- Jin Hyuk Jung
- Section on Islet Cell and Regenerative Biology Joslin Diabetes Center, Boston, MA 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Kumiko Iwabuchi
- Section on Islet Cell and Regenerative Biology Joslin Diabetes Center, Boston, MA 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Zhihong Yang
- Section on Islet Cell and Regenerative Biology Joslin Diabetes Center, Boston, MA 02215, USA.,Section on Vascular Cell Biology Harvard Medical School, Boston, MA 02115, USA
| | - Mary R Loeken
- Section on Islet Cell and Regenerative Biology Joslin Diabetes Center, Boston, MA 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
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Wei D, Loeken MR. Increased DNA methyltransferase 3b (Dnmt3b)-mediated CpG island methylation stimulated by oxidative stress inhibits expression of a gene required for neural tube and neural crest development in diabetic pregnancy. Diabetes 2014; 63:3512-22. [PMID: 24834974 PMCID: PMC4171658 DOI: 10.2337/db14-0231] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 05/10/2014] [Indexed: 12/31/2022]
Abstract
Previous studies have shown that diabetic embryopathy results from impaired expression of genes that are required for formation of embryonic structures. We have focused on Pax3, a gene that is expressed in embryonic neuroepithelium and is required for neural tube closure. Pax3 expression is inhibited in embryos of diabetic mice due to hyperglycemia-induced oxidative stress. DNA methylation silences developmentally expressed genes before differentiation. We hypothesized that hypomethylation of Pax3 upon neuroepithelial differentiation may be inhibited by hyperglycemia-induced oxidative stress. We tested this using embryos of pregnant hyperglycemic mice and mouse embryonic stem cells (ESC). Methylation of a Pax3 CpG island decreased upon neurulation of embryos and formation of neuronal precursors from ESC. In ESC, this was inhibited by oxidative stress. Use of short hairpin RNA in ESC demonstrated that DNA methyltransferase 3b (Dnmt3b) was responsible for methylation and silencing of Pax3 before differentiation and by oxidative stress. Although expression of Dnmt3b was not affected by oxidative stress, DNA methyltransferase activity was increased. These results indicate that hyperglycemia-induced oxidative stress stimulates Dnmt3b activity, thereby inhibiting chromatin modifications necessary for induction of Pax3 expression during neurulation and thus providing a molecular mechanism for defects caused by Pax3 insufficiency in diabetic pregnancy.
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Affiliation(s)
- Dan Wei
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, and Department of Medicine, Harvard Medical School, Boston, MA
| | - Mary R Loeken
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, and Department of Medicine, Harvard Medical School, Boston, MA
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Sanders K, Jung JH, Loeken MR. Use of a murine embryonic stem cell line that is sensitive to high glucose environment to model neural tube development in diabetic pregnancy. ACTA ACUST UNITED AC 2014; 100:584-91. [PMID: 25124397 DOI: 10.1002/bdra.23281] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 06/09/2014] [Accepted: 06/18/2014] [Indexed: 11/09/2022]
Abstract
BACKGROUND Neural tube defects (NTDs) are significantly increased by maternal diabetes. Embryonic stem cells (ESC) that can differentiate into neuroepithelium and can sense supraphysiological glucose concentrations would be very valuable to simulate the effects of maternal diabetes on molecular and cellular processes during neural tube formation. METHODS LG-ESC, a recently established ESC line that expresses the glucose transporter, Scl2a2, and is sensitive to elevated glucose concentrations, were grown for up to 8 days in a three-dimensional culture to form neural cysts. We tested whether high glucose media inhibits expression of Pax3, a gene that is required for neural tube closure and whose expression is inhibited in embryos of diabetic mice, and inhibits formation of neural cysts. RESULTS Pax3 expression was detected after 4 days of culture and increased with time. Pax3 expression was inhibited by high glucose media, but not if cells had been cultured in low glucose media for the first 4 days of culture. Pax7, which is also expressed in dorsal neural tube, was not detected. Pax6, which is expressed in the ventral neural tube, was detected only after 8 days of culture, but was not inhibited by high glucose. High glucose media did not inhibit formation of neural cysts. CONCLUSION LG-ESC can be used as a model of embryonic exposure to a diabetic environment during neural tube development. While high glucose exposure inhibits expression of a gene required for neural tube closure, it may not inhibit all of the processes involved in formation of a neural tube-like structure.
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Affiliation(s)
- Kaitlyn Sanders
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Boston, Massachusetts
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Loeken MR. Intersection of complex genetic traits affecting maternal metabolism, fetal metabolism, and neural tube defect risk: looking for needles in multiple haystacks. Mol Genet Metab 2014; 111:415-7. [PMID: 24503137 PMCID: PMC3982189 DOI: 10.1016/j.ymgme.2014.01.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Accepted: 01/18/2014] [Indexed: 12/25/2022]
Affiliation(s)
- Mary R Loeken
- Section on Islet and Regenerative Cell Biology, Joslin Diabetes Center, One Joslin Place, Boston, MA 02215, USA.
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