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Druzak SA, Tardelli M, Mays SG, El Bejjani M, Mo X, Maner-Smith KM, Bowen T, Cato ML, Tillman MC, Sugiyama A, Xie Y, Fu H, Cohen DE, Ortlund EA. Ligand dependent interaction between PC-TP and PPARδ mitigates diet-induced hepatic steatosis in male mice. Nat Commun 2023; 14:2748. [PMID: 37173315 PMCID: PMC10182070 DOI: 10.1038/s41467-023-38010-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 04/12/2023] [Indexed: 05/15/2023] Open
Abstract
Phosphatidylcholine transfer protein (PC-TP; synonym StarD2) is a soluble lipid-binding protein that transports phosphatidylcholine (PC) between cellular membranes. To better understand the protective metabolic effects associated with hepatic PC-TP, we generated a hepatocyte-specific PC-TP knockdown (L-Pctp-/-) in male mice, which gains less weight and accumulates less liver fat compared to wild-type mice when challenged with a high-fat diet. Hepatic deletion of PC-TP also reduced adipose tissue mass and decreases levels of triglycerides and phospholipids in skeletal muscle, liver and plasma. Gene expression analysis suggest that the observed metabolic changes are related to transcriptional activity of peroxisome proliferative activating receptor (PPAR) family members. An in-cell protein complementation screen between lipid transfer proteins and PPARs uncovered a direct interaction between PC-TP and PPARδ that was not observed for other PPARs. We confirmed the PC-TP- PPARδ interaction in Huh7 hepatocytes, where it was found to repress PPARδ-mediated transactivation. Mutations of PC-TP residues implicated in PC binding and transfer reduce the PC-TP-PPARδ interaction and relieve PC-TP-mediated PPARδ repression. Reduction of exogenously supplied methionine and choline reduces the interaction while serum starvation enhances the interaction in cultured hepatocytes. Together our data points to a ligand sensitive PC-TP- PPARδ interaction that suppresses PPAR activity.
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Affiliation(s)
- Samuel A Druzak
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA
| | - Matteo Tardelli
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
| | - Suzanne G Mays
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA
| | - Mireille El Bejjani
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA
| | - Xulie Mo
- Department of Chemical Biology and Pharmacology, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA
| | - Kristal M Maner-Smith
- Emory Integrated Lipidomics and Metabolomics Core, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA
| | - Thomas Bowen
- Emory Integrated Lipidomics and Metabolomics Core, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA
| | - Michael L Cato
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA
| | - Matthew C Tillman
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA
| | - Akiko Sugiyama
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
- Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Yang Xie
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
- Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Haian Fu
- Department of Chemical Biology and Pharmacology, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA
| | - David E Cohen
- Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
- Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, 1510 Clifton Road, Atlanta, GA, USA.
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2
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Liebmann M, Asuaje Pfeifer M, Grupe K, Scherneck S. Estradiol (E2) Improves Glucose-Stimulated Insulin Secretion and Stabilizes GDM Progression in a Prediabetic Mouse Model. Int J Mol Sci 2022; 23:ijms23126693. [PMID: 35743136 PMCID: PMC9223537 DOI: 10.3390/ijms23126693] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/11/2022] [Accepted: 06/14/2022] [Indexed: 01/27/2023] Open
Abstract
Female New Zealand obese (NZO) mice are an established model of preconceptional (pc.) prediabetes that progresses as gestational diabetes mellitus (GDM) during gestation. It is known that NZO mice show improvement in insulin sensitivity and glucose-stimulated insulin secretion (GSIS) during gestation in vivo. The latter is no longer detectable in ex vivo perifusion experiments in isolated islets of Langerhans, suggesting a modulation by extrapancreatic factors. Here, we demonstrated that plasma 17β-estradiol (E2) levels increased markedly in NZO mice during gestation. The aim of this work was to determine whether these increased E2 levels are responsible for the improvement in metabolism during gestation. To achieve this goal, we examined its effects in isolated islets and primary hepatocytes of both NZO and metabolically healthy NMRI mice. E2 increased GSIS in the islets of both strains significantly. Hepatic glucose production (HGP) failed to be decreased by insulin in NZO hepatocytes but was reduced by E2 in both strains. Hepatocytes of pregnant NZO mice showed significantly lower glucose uptake (HGU) compared with NMRI controls, whereby E2 stimulation diminished this difference. Hepatocytes of pregnant NZO showed reduced glycogen content, increased cyclic adenosine monophosphate (cAMP) levels, and reduced AKT activation. These differences were abolished after E2 stimulation. In conclusion, our data indicate that E2 stabilizes and prevents deterioration of the metabolic state of the prediabetic NZO mice. E2 particularly increases GSIS and improves hepatic glucose utilization to a lower extent.
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Lone IM, Iraqi FA. Genetics of murine type 2 diabetes and comorbidities. Mamm Genome 2022; 33:421-436. [PMID: 35113203 DOI: 10.1007/s00335-022-09948-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 01/18/2022] [Indexed: 12/15/2022]
Abstract
ABSTRAC Type 2 diabetes (T2D) is a polygenic and multifactorial complex disease, defined as chronic metabolic disorder. It's a major global health concern with an estimated 463 million adults aged 20-79 years with diabetes and projected to increase up to 700 million by 2045. T2D was reported to be one of the four leading causes of non-communicable disease (NCD) deaths in 2012. Environmental factors play a part in the development of polygenic forms of diabetes. Polygenic forms of diabetes often run-in families. Fortunately, T2D, which accounts for 90-95% of the entire four types of diabetes including, Type 1 diabetes (T1D), T2D, monogenic diabetes syndromes (MGDS), and Gestational diabetes mellitus, can be prevented or delayed through nutrition and lifestyle changes as well as through pharmacologic interventions. Typical symptom of the T2D is high blood glucose levels and comprehensive insulin resistance of the body, producing an impaired glucose tolerance. Impaired glucose tolerance of T2D is accompanied by extensive health complications, including cardiovascular diseases (CVD) that vary in morbidity and mortality among populations. The pathogenesis of T2D varies between populations and/or ethnic groupings and is known to be attributed extremely by genetic components and environmental factors. It is evident that genetic background plays a critical role in determining the host response toward certain environmental conditions, whether or not of developing T2D (susceptibility versus resistant). T2D is considered as a silent disease that can progress for years before its diagnosis. Once T2D is diagnosed, many metabolic malfunctions are observed whether as side effects or as independent comorbidity. Mouse models have been proven to be a powerful tool for mapping genetic factors that underline the susceptibility to T2D development as well its comorbidities. Here, we have conducted a comprehensive search throughout the published data covering the time span from early 1990s till the time of writing this review, for already reported quantitative trait locus (QTL) associated with murine T2D and comorbidities in different mouse models, which contain different genetic backgrounds. Our search has resulted in finding 54 QTLs associated with T2D in addition to 72 QTLs associated with comorbidities associated with the disease. We summarized the genomic locations of these mapped QTLs in graphical formats, so as to show the overlapping positions between of these mapped QTLs, which may suggest that some of these QTLs could be underlined by sharing gene/s. Finally, we reviewed and addressed published reports that show the success of translation of the identified mouse QTLs/genes associated with the disease in humans.
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Affiliation(s)
- Iqbal M Lone
- Department of Clinical Microbiology & Immunology, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, 69978, Tel-Aviv, Israel
| | - Fuad A Iraqi
- Department of Clinical Microbiology & Immunology, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, 69978, Tel-Aviv, Israel.
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4
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Barakat M, DiPietro LA, Chen L. Limited Treatment Options for Diabetic Wounds: Barriers to Clinical Translation Despite Therapeutic Success in Murine Models. Adv Wound Care (New Rochelle) 2021; 10:436-460. [PMID: 33050829 PMCID: PMC8236303 DOI: 10.1089/wound.2020.1254] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 10/12/2020] [Indexed: 12/15/2022] Open
Abstract
Significance: Millions of people worldwide suffer from diabetes mellitus and its complications, including chronic diabetic wounds. To date, there are few widely successful clinical therapies specific to diabetic wounds beyond general wound care, despite the vast number of scientific discoveries in the pathogenesis of defective healing in diabetes. Recent Advances: In recent years, murine animal models of diabetes have enabled the investigation of many possible therapeutics for diabetic wound care. These include specific cell types, growth factors, cytokines, peptides, small molecules, plant extracts, microRNAs, extracellular vesicles, novel wound dressings, mechanical interventions, bioengineered materials, and more. Critical Issues: Despite many research discoveries, few have been translated from their success in murine models to clinical use in humans. This massive gap between bench discovery and bedside application begs the simple and critical question: what is still missing? The complexity and multiplicity of the diabetic wound makes it an immensely challenging therapeutic target, and this lopsided progress highlights the need for new methods to overcome the bench-to-bedside barrier. How can laboratory discoveries in animal models be effectively translated to novel clinical therapies for human patients? Future Directions: As research continues to decipher deficient healing in diabetes, new approaches and considerations are required to ensure that these discoveries can become translational, clinically usable therapies. Clinical progress requires the development of new, more accurate models of the human disease state, multifaceted investigations that address multiple critical components in wound repair, and more innovative research strategies that harness both the existing knowledge and the potential of new advances across disciplines.
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Affiliation(s)
- May Barakat
- Center for Wound Repair and Tissue Regeneration, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Luisa A. DiPietro
- Center for Wound Repair and Tissue Regeneration, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Lin Chen
- Center for Wound Repair and Tissue Regeneration, College of Dentistry, University of Illinois at Chicago, Chicago, Illinois, USA
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Rehman SU, Schallschmidt T, Rasche A, Knebel B, Stermann T, Altenhofen D, Herwig R, Schürmann A, Chadt A, Al-Hasani H. Alternative exon splicing and differential expression in pancreatic islets reveals candidate genes and pathways implicated in early diabetes development. Mamm Genome 2021; 32:153-172. [PMID: 33880624 PMCID: PMC8128753 DOI: 10.1007/s00335-021-09869-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 04/03/2021] [Indexed: 12/29/2022]
Abstract
Type 2 diabetes (T2D) has a strong genetic component. Most of the gene variants driving the pathogenesis of T2D seem to target pancreatic β-cell function. To identify novel gene variants acting at early stage of the disease, we analyzed whole transcriptome data to identify differential expression (DE) and alternative exon splicing (AS) transcripts in pancreatic islets collected from two metabolically diverse mouse strains at 6 weeks of age after three weeks of high-fat-diet intervention. Our analysis revealed 1218 DE and 436 AS genes in islets from NZO/Hl vs C3HeB/FeJ. Whereas some of the revealed genes present well-established markers for β-cell failure, such as Cd36 or Aldh1a3, we identified numerous DE/AS genes that have not been described in context with β-cell function before. The gene Lgals2, previously associated with human T2D development, was DE as well as AS and localizes in a quantitative trait locus (QTL) for blood glucose on Chr.15 that we reported recently in our N2(NZOxC3H) population. In addition, pathway enrichment analysis of DE and AS genes showed an overlap of only half of the revealed pathways, indicating that DE and AS in large parts influence different pathways in T2D development. PPARG and adipogenesis pathways, two well-established metabolic pathways, were overrepresented for both DE and AS genes, probably as an adaptive mechanism to cope for increased cellular stress. Our results provide guidance for the identification of novel T2D candidate genes and demonstrate the presence of numerous AS transcripts possibly involved in islet function and maintenance of glucose homeostasis.
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Affiliation(s)
- Sayeed Ur Rehman
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Duesseldorf, Germany.,German Center for Diabetes Research (DZD), München-Neuherberg, Germany.,Department of Biochemistry, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi, 110062, India
| | - Tanja Schallschmidt
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Duesseldorf, Germany.,German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Axel Rasche
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Birgit Knebel
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Duesseldorf, Germany.,German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Torben Stermann
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Duesseldorf, Germany.,German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Delsi Altenhofen
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Duesseldorf, Germany.,German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Ralf Herwig
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Annette Schürmann
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany.,German Institute of Human Nutrition, Potsdam, Germany
| | - Alexandra Chadt
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Duesseldorf, Germany.,German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Hadi Al-Hasani
- Institute for Clinical Biochemistry and Pathobiochemistry, German Diabetes Center (DDZ), Leibniz Center for Diabetes Research at Heinrich Heine University, Medical Faculty, Duesseldorf, Germany. .,German Center for Diabetes Research (DZD), München-Neuherberg, Germany.
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6
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Jones PH, Deng B, Winkler J, Zirnheld AL, Ehringer S, Shetty V, Cox M, Nguyen H, Shen WJ, Huang TT, Wang E. Over-expression of miR-34c leads to early-life visceral fat accumulation and insulin resistance. Sci Rep 2019; 9:13844. [PMID: 31554925 PMCID: PMC6761099 DOI: 10.1038/s41598-019-50191-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 08/15/2019] [Indexed: 12/13/2022] Open
Abstract
Overweight children and adolescents are at high risk for adult and late life obesity. This report investigates some underlying mechanisms contributing to obesity during early life in an animal model. We generated a strain of transgenic mice, cU2, overexpressing human microRNA 34c, a microRNA functionally implicated in adipogenesis. Male and female cU2 mice exhibit significant weight gain, accompanied by marked increase in abdominal fat mass and metabolic abnormalities, including reduction of both glucose clearance rate and insulin sensitivity, as early as two months of age. Adipogenesis derailment at this early age is suggested by decreased expression of adiponectin, the fat mass and obesity-associated gene, and the adiponectin receptor R1, coupled with a reduction of the brown fat biomarker PAT2 and the adipogenesis inhibitor SIRT1. Notably, adiponectin is an important adipokine and an essential regulator of glucose and fatty acid homeostasis. cU2 mice may provide a crucial animal model for investigating the role of miR-34c in early onset insulin resistance and visceral fat mass increase, contributing to accelerated body weight gain and metabolic disorders. Intervention in this dysregulation may open a new preventive strategy to control early-life weight gain and abnormal insulin resistance, and thus prevalent adult and late life obesity.
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Affiliation(s)
| | - Brian Deng
- Palo Alto Veterans Institute for Research, Palo Alto, CA, USA.,Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | | | | | | | | | - Matthew Cox
- Advanced Genomic Technology, LLC, Louisville, KY, USA
| | - Huy Nguyen
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA
| | - Wen-Jun Shen
- Department of Endocrinology, Stanford University School of Medicine, Stanford, CA, USA.,Geriatric Research, Education, and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA, USA
| | - Ting-Ting Huang
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA. .,Geriatric Research, Education, and Clinical Center, VA Palo Alto Health Care System, Palo Alto, CA, USA.
| | - Eugenia Wang
- Advanced Genomic Technology, LLC, Louisville, KY, USA
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7
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Mishra A, Cross M, Hofmann A, Coster MJ, Karim A, Sattar A. Identification of a Novel Scaffold for Inhibition of Dipeptidyl Peptidase-4. J Comput Biol 2019; 26:1470-1486. [PMID: 31390221 DOI: 10.1089/cmb.2019.0201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Dipeptidyl peptidase-4 (DPP-4) is considered a major drug target for type 2 diabetes mellitus (T2DM). In addition to T2DM, a regulatory role of DPP-4 was also found in cardiovascular diseases. Existing DPP-4 inhibitors have been reported to have several adverse effects. In this study, a computer-aided drug design approach and its use to detect a novel class of inhibitor for DPP-4 are reported. Through structure and pharmacophore-based screening, we identified 13 hit compounds from an ∼4-million-compound library. Physical interactions of these hits with DPP-4 were studied using docking and explicit solvent molecular dynamics (MD) simulations. Later, MMPBSA binding energy was calculated for the ligand/protein simulation trajectories to determine the stability of compounds in the binding cavity. These compounds have a novel scaffold and exhibited a stable binding mode. "Best-in-screen" compounds (or their closest available analogs) were resourced and their inhibition of DPP-4 activity was experimentally validated using an in vitro enzyme activity assay in the presence of 100 and 10 μM compounds. These assays identified a compound with a spirochromanone center with 53% inhibition activity at a 100 μM concentration. A further five spirochromanone compounds were synthesized and examined in silico and in vitro; again, one compound showed 53% inhibitory activity action at 100 μM. Overall, this study identified two novel "spirochromanone" compounds that lowered DPP-4 activity by more than ∼50% at 100 μM. This study also showed the impact of fast in silico drug design techniques utilizing virtual screening and MD to identify novel scaffolds to bind and inhibit DPP-4. Spirochromanone motif identified here may be used to design molecules to achieve drug-like inhibitory action against DPP-4.
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Affiliation(s)
- Avinash Mishra
- Institute for Integrated and Intelligent Systems, Griffith University, Nathan, Australia.,Novo Informatics Pvt. Ltd., New Delhi, India
| | - Megan Cross
- Griffith Institute for Drug Discovery, Griffith University, Nathan, Australia
| | - Andreas Hofmann
- Griffith Institute for Drug Discovery, Griffith University, Nathan, Australia.,Faculty of Veterinary and Agricultural Sciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Australia
| | - Mark J Coster
- Griffith Institute for Drug Discovery, Griffith University, Nathan, Australia
| | - Abdul Karim
- Institute for Integrated and Intelligent Systems, Griffith University, Nathan, Australia
| | - Abdul Sattar
- Institute for Integrated and Intelligent Systems, Griffith University, Nathan, Australia
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8
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Two Novel Candidate Genes for Insulin Secretion Identified by Comparative Genomics of Multiple Backcross Mouse Populations. Genetics 2018; 210:1527-1542. [PMID: 30341086 DOI: 10.1534/genetics.118.301578] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 10/16/2018] [Indexed: 12/28/2022] Open
Abstract
To identify novel disease genes for type 2 diabetes (T2D) we generated two backcross populations of obese and diabetes-susceptible New Zealand Obese (NZO/HI) mice with the two lean mouse strains 129P2/OlaHsd and C3HeB/FeJ. Subsequent whole-genome linkage scans revealed 30 novel quantitative trait loci (QTL) for T2D-associated traits. The strongest association with blood glucose [12 cM, logarithm of the odds (LOD) 13.3] and plasma insulin (17 cM, LOD 4.8) was detected on proximal chromosome 7 (designated Nbg7p, NZO blood glucose on proximal chromosome 7) exclusively in the NZOxC3H crossbreeding, suggesting that the causal gene is contributed by the C3H genome. Introgression of the critical C3H fragment into the genetic NZO background by generating recombinant congenic strains and metabolic phenotyping validated the phenotype. For the detection of candidate genes in the critical region (30-46 Mb), we used a combined approach of haplotype and gene expression analysis to search for C3H-specific gene variants in the pancreatic islets, which appeared to be the most likely target tissue for the QTL. Two genes, Atp4a and Pop4, fulfilled the criteria from our candidate gene approaches. The knockdown of both genes in MIN6 cells led to decreased glucose-stimulated insulin secretion, indicating a regulatory role of both genes in insulin secretion, thereby possibly contributing to the phenotype linked to Nbg7p In conclusion, our combined- and comparative-cross analysis approach has successfully led to the identification of two novel diabetes susceptibility candidate genes, and thus has been proven to be a valuable tool for the discovery of novel disease genes.
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Application of Personalized, Predictive, Preventative, and Participatory (P4) Medicine to Obstructive Sleep Apnea. A Roadmap for Improving Care? Ann Am Thorac Soc 2018; 13:1456-67. [PMID: 27387483 DOI: 10.1513/annalsats.201604-235ps] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Dr. Leroy Hood promotes a paradigm to advance medical care that he calls P4 medicine. The four Ps are: personalized, predictive, preventative, and participatory. P4 medicine encourages a convergence of systems medicine, the digital revolution, and consumer-driven healthcare. Might P4 medicine be applicable to obstructive sleep apnea (OSA)? OSA should be personalized in that there are different structural and physiological pathways to disease. Obesity is a major risk factor. The link between obesity and OSA is likely to be fat deposits in the tongue compromising the upper airway. Clinical features at presentation also vary between patients. There are three distinct subgroups: (1) patients with a primary complaint of insomnia, (2) relatively asymptomatic patients with a high prevalence of cardiovascular comorbidities, and (3) excessively sleepy patients. Currently, there have been limited efforts to identify subgroups of patients on the basis of measures obtained by polysomnography. Yet, these diagnostic studies likely contain considerable predictive information. Likewise, there has currently been limited application of -omic approaches. Determining the relative role of obesity and OSA for particular consequences is challenging, because they both affect the same molecular pathways. There is evidence that the effects of OSA are modified by the level of obesity. These insights may lead to improvements in predicting outcomes to personalized therapies. The final P-participatory-is ideally suited to OSA, with technology to obtain extensive data remotely from continuous positive airway pressure machines. Providing adherence data directly to patients increases their use of continuous positive airway pressure. Thus, the concept of P4 medicine is very applicable to obstructive sleep apnea and can be the basis for future research efforts.
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10
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Skeletal muscle mitochondrial uncoupling prevents diabetes but not obesity in NZO mice, a model for polygenic diabesity. GENES AND NUTRITION 2015; 10:57. [PMID: 26584809 DOI: 10.1007/s12263-015-0507-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 11/04/2015] [Indexed: 01/04/2023]
Abstract
Induction of skeletal muscle (SM) mitochondrial stress by expression of uncoupling protein 1 (UCP1) in mice results in a healthy metabolic phenotype associated with increased secretion of FGF21 from SM. Here, we investigated whether SM mitochondrial uncoupling can compensate obesity and insulin resistance in the NZO mouse, a polygenic diabesity model. Male NZO mice were crossed with heterozygous UCP1 transgenic (tg) mice (mixed C57BL/6/CBA background) and further backcrossed to obtain F1 and N2 offspring with 50 and 75 % NZO background, respectively. Male F1 and N2 progeny were fed a high-fat diet ad libitum for 20 weeks from weaning. Blood glucose was reduced, and diabetes (severe hyperglycemia >300 mg/dl) was fully prevented in both F1- and N2-tg progeny compared to a diabetes prevalence of 15 % in F1 and 42 % in N2 wild type. In contrast, relative body fat content and plasma insulin were decreased, and glucose tolerance was improved, in F1-tg only. Both F1 and N2-tg showed decreased lean body mass. Accordingly, induction of SM stress response including FGF21 expression and secretion was similar in both F1 and N2-tg mice. In white adipose tissue, expression of FGF21 target genes was enhanced in F1 and N2-tg mice, whereas lipid metabolism genes were induced in F1-tg only. There was no evidence for induction of browning in either UCP1 backcross. We conclude that SM mitochondrial uncoupling induces FGF21 expression and prevents diabetes in mice with a 50-75 % NZO background independent of its effects on adipose tissue.
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11
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Märker T, Kriebel J, Wohlrab U, Burkart V, Habich C. Adipocytes from New Zealand obese mice exhibit aberrant proinflammatory reactivity to the stress signal heat shock protein 60. J Diabetes Res 2014; 2014:187153. [PMID: 24672802 PMCID: PMC3941600 DOI: 10.1155/2014/187153] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Revised: 11/29/2013] [Accepted: 12/03/2013] [Indexed: 11/29/2022] Open
Abstract
Adipocytes release immune mediators that contribute to diabetes-associated inflammatory processes. As the stress protein heat shock protein 60 (Hsp60) induces proinflammatory adipocyte activities, we hypothesized that adipocytes of diabetes-predisposed mice exhibit an increased proinflammatory reactivity to Hsp60. Preadipocytes and mature adipocytes from nonobese diabetic (NOD), New Zealand obese (NZO), and C57BL/6J mice were analyzed for Hsp60 binding, Hsp60-activated signaling pathways, and Hsp60-induced release of the chemokine CXCL-1 (KC), interleukin 6 (IL-6), and macrophage chemoattractant protein-1 (MCP-1). Hsp60 showed specific binding to (pre-)adipocytes of NOD, NZO, and C57BL/6J mice. Hsp60 binding involved conserved binding structure(s) and Hsp60 epitopes and was strongest to NZO mouse-derived mature adipocytes. Hsp60 exposure induced KC, IL-6, and MCP-1 release from (pre-)adipocytes of all mouse strains with a pronounced increase of IL-6 release from NZO mouse-derived adipocytes. Compared to NOD and C57BL/6J mouse derived cells, Hsp60-induced formation of IL-6, KC, and MCP-1 from NZO mouse-derived (pre-)adipocytes strongly depended on NF κ B-activation. Increased Hsp60 binding and Hsp60-induced IL-6 release by mature adipocytes of NZO mice suggest that enhanced adipocyte reactivity to the stress signal Hsp60 contributes to inflammatory processes underlying diabetes associated with obesity and insulin resistance.
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Affiliation(s)
- Tina Märker
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, the Heinrich-Heine-University Düsseldorf, Auf'm Hennekamp 65, 40225 Düsseldorf, Germany
| | - Jennifer Kriebel
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, the Heinrich-Heine-University Düsseldorf, Auf'm Hennekamp 65, 40225 Düsseldorf, Germany
| | - Ulrike Wohlrab
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, the Heinrich-Heine-University Düsseldorf, Auf'm Hennekamp 65, 40225 Düsseldorf, Germany
| | - Volker Burkart
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, the Heinrich-Heine-University Düsseldorf, Auf'm Hennekamp 65, 40225 Düsseldorf, Germany
- German Center for Diabetes Research (DZD e.V.), Düsseldorf, Germany
- *Volker Burkart:
| | - Christiane Habich
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, the Heinrich-Heine-University Düsseldorf, Auf'm Hennekamp 65, 40225 Düsseldorf, Germany
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Zhang W, Tang M, Zhong M, Wang Z, Shang Y, Gong H, Zhang Y, Zhang W. Association of the six transmembrane protein of prostate 2 gene polymorphisms with metabolic syndrome in Han Chinese population. Diabetes Metab Syndr 2013; 7:138-142. [PMID: 23953178 DOI: 10.1016/j.dsx.2013.06.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
AIM The six-transmembrane protein of prostate 2 (STAMP2) has been demonstrated to play a potential role in the pathogenesis of metabolic syndrome (MetS). The present study was designed to investigate the association of STAMP2 gene polymorphisms with MetS in Han Chinese population. METHODS A case-control study enrolled 350 Han Chinese subjects in two groups: 182 MetS patients and 168 control subjects. The clinical and biochemical characteristics were determined. Three single nucleotide polymorphisms (SNPs), rs1981529, rs12386756 and rs10263111 in STAMP2 gene were genotyped. The association of STAMP2 gene polymorphisms with MetS was analyzed. RESULTS SNPs rs1981529 and rs10263111 were found to be significantly associated with MetS phenotype in male population (P=0.014 and 0.025). Moreover, SNP rs1981529 was found to be associated with high density lipoprotein-cholesterol in male cases and with body mass index in female cases (P=0.014 and 0.049). SNP rs10263111 was found to be associated with both waist circumference and diastolic blood pressure in total cases (P=0.044 and 0.033). Haplotype analysis yielded significant association of STAMP2 gene with MetS in total (global P=0.0109) and male population (global P=0.0004). CONCLUSION Our findings revealed that STAMP2 gene polymorphisms are likely to significantly contribute to the risk of MetS in male Han Chinese population.
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Affiliation(s)
- Wenchao Zhang
- Qilu Hospital of Shandong University, Jinan, Shandong 250012, PR China
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Abstract
The focus of this overview is on the animal models of obesity most commonly utilized in research. The models include monogenic models in the leptin pathway, polygenic diet-dependent models, and, in particular for their historical perspective, surgical and chemical models of obesity. However, there are far too many models to consider all of them comprehensively, especially those caused by selective molecular genetic approaches modifying one or more genes in specific populations of cells. Further, the generation and use of inducible transgenic animals (induced knock-out or knock-in) is not covered, even though they often carry significant advantages compared to traditional transgenic animals, e.g., influences of the genetic modification during the development of the animals can be minimized. The number of these animal models is simply too large to be covered in this unit.
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Affiliation(s)
- Thomas A Lutz
- University of Zurich, Institute of Veterinary Physiology, Zurich Center of Integrative Human Physiology, Zurich, Switzerland
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Kluge R, Scherneck S, Schürmann A, Joost HG. Pathophysiology and genetics of obesity and diabetes in the New Zealand obese mouse: a model of the human metabolic syndrome. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2012; 933:59-73. [PMID: 22893401 DOI: 10.1007/978-1-62703-068-7_5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The New Zealand Obese (NZO) mouse is one of the most thoroughly investigated polygenic models for the human metabolic syndrome and type 2 diabetes. It presents the main characteristics of the disease complex, including early-onset obesity, insulin resistance, dyslipidemia, and hypertension. As a consequence of this syndrome, a combination of lipotoxicity and glucotoxicity produces beta-cell failure and apoptosis resulting in hypoinsulinemia and diabetic hyperglycemia. With NZO as a breeding partner, several adipogenic and diabetogenic gene variants have been identified by hypothesis-free positional cloning (Tbc1d1, Zfp69) or by combining genetic screens and candidate gene approaches (Pctp, Abcg1, Nmur2, Lepr). This chapter summarizes the present knowledge of the NZO strain and describes its pathophysiology as well as the known underlying genetic defects.
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Affiliation(s)
- Reinhart Kluge
- Max-Rubner-Laboratory, German Institute of Human Nutrition Potsdam-Rehbrücke, Nuthetal, Germany.
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Kim JH, Saxton AM. The TALLYHO mouse as a model of human type 2 diabetes. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2012; 933:75-87. [PMID: 22893402 DOI: 10.1007/978-1-62703-068-7_6] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
The TALLYHO/Jng (TH) mouse is an inbred polygenic model for type 2 diabetes (T2D) with moderate obesity. Both male and female TH mice are characterized by increased body and fat pad weights, hyperleptinemia, hyperinsulinemia, and hyperlipidemia. Glucose intolerance and hyperglycemia are exhibited only in males. Reduced 2-deoxy-glucose uptake occurs in adipose tissue and skeletal muscle of male TH mice. While both sexes of TH mice exhibit enlarged pancreatic islets, only males have degranulation and abnormal architecture in islets. Endothelial dysfunction and considerably decreased bone density are also observed in male TH mice. The blood pressure of male TH mice is normal. Genetic outcross experiments with non-diabetic strains revealed multiple susceptibility loci (quantitative trait loci) for obesity, hypertriglyceridemia, hypercholesterolemia, and hyperglycemia. In conclusion, TH mice encompass many aspects of polygenic human diabetes and are a very useful model for T2D.
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Affiliation(s)
- Jung Han Kim
- Department of Pharmacology, Physiology and Toxicology, Marshall University School of Medicine, Huntington, WV, USA.
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