1
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Gedawy A, Al-Salami H, Dass CR. Polydimethylsiloxane Organic-Inorganic Composite Drug Reservoir with Gliclazide. Int J Mol Sci 2024; 25:3991. [PMID: 38612802 PMCID: PMC11012350 DOI: 10.3390/ijms25073991] [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: 02/29/2024] [Revised: 03/29/2024] [Accepted: 03/29/2024] [Indexed: 04/14/2024] Open
Abstract
A novel organic-inorganic gliclazide-loaded composite bead was developed by an ionic gelation process using acidified CaCl2, chitosan and tetraethylorthosilicate (TEOS) as a crosslinker. The beads were manufactured by crosslinking an inorganic silicone elastomer (-OH terminated polydimethylsiloxane, PDMS) with TEOS at different ratios before grafting onto an organic backbone (Na-alginate) using a 32 factorial experimental design. Gliclazide's encapsulation efficiency (EE%) and drug release over 8 h (% DR 8 h) were set as dependent responses for the optimisation of a pharmaceutical formula (herein referred to as 'G op') by response surface methodology. EE % and %DR 8 h of G op were 93.48% ± 0.19 and 70.29% ± 0.18, respectively. G op exhibited a controlled release of gliclazide that follows the Korsmeyer-Peppas kinetic model (R2 = 0.95) with super case II transport and pH-dependent swelling behaviour. In vitro testing of G op showed 92.17% ± 1.18 cell viability upon testing on C2C12 myoblasts, indicating the compatibility of this novel biomaterial platform with skeletal muscle drug delivery.
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Affiliation(s)
- Ahmed Gedawy
- Curtin Medical School, Curtin University, Bentley 6102, Australia; (A.G.); (H.A.-S.)
- Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Australia
| | - Hani Al-Salami
- Curtin Medical School, Curtin University, Bentley 6102, Australia; (A.G.); (H.A.-S.)
- Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Australia
| | - Crispin R. Dass
- Curtin Medical School, Curtin University, Bentley 6102, Australia; (A.G.); (H.A.-S.)
- Curtin Health Innovation Research Institute, Curtin University, Bentley 6102, Australia
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2
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Maciejewska-Skrendo A, Massidda M, Tocco F, Leźnicka K. The Influence of the Differentiation of Genes Encoding Peroxisome Proliferator-Activated Receptors and Their Coactivators on Nutrient and Energy Metabolism. Nutrients 2022; 14:nu14245378. [PMID: 36558537 PMCID: PMC9782515 DOI: 10.3390/nu14245378] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/27/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022] Open
Abstract
Genetic components may play an important role in the regulation of nutrient and energy metabolism. In the presence of specific genetic variants, metabolic dysregulation may occur, especially in relation to the processes of digestion, assimilation, and the physiological utilization of nutrients supplied to the body, as well as the regulation of various metabolic pathways and the balance of metabolic changes, which may consequently affect the effectiveness of applied reduction diets and weight loss after training. There are many well-documented studies showing that the presence of certain polymorphic variants in some genes can be associated with specific changes in nutrient and energy metabolism, and consequently, with more or less desirable effects of applied caloric reduction and/or exercise intervention. This systematic review focused on the role of genes encoding peroxisome proliferator-activated receptors (PPARs) and their coactivators in nutrient and energy metabolism. The literature review prepared showed that there is a link between the presence of specific alleles described at different polymorphic points in PPAR genes and various human body characteristics that are crucial for the efficacy of nutritional and/or exercise interventions. Genetic analysis can be a valuable element that complements the work of a dietitian or trainer, allowing for the planning of a personalized diet or training that makes the best use of the innate metabolic characteristics of the person who is the subject of their interventions.
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Affiliation(s)
- Agnieszka Maciejewska-Skrendo
- Faculty of Physical Culture, Gdansk University of Physical Education and Sport, 80-336 Gdansk, Poland
- Institute of Physical Culture Sciences, University of Szczecin, 71-065 Szczecin, Poland
- Correspondence:
| | - Myosotis Massidda
- Department of Medical Sciences and Public Health, Faculty of Medicine and Surgery, Sport and Exercise Sciences Degree Courses, University of Cagliari, 72-09124 Cagliari, Italy
| | - Filippo Tocco
- Department of Medical Sciences and Public Health, Faculty of Medicine and Surgery, Sport and Exercise Sciences Degree Courses, University of Cagliari, 72-09124 Cagliari, Italy
| | - Katarzyna Leźnicka
- Faculty of Physical Culture, Gdansk University of Physical Education and Sport, 80-336 Gdansk, Poland
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3
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Alghanem L, Zhang X, Jaiswal R, Seyoum B, Mallisho A, Msallaty Z, Yi Z. Effect of Insulin and Pioglitazone on Protein Phosphatase 2A Interaction Partners in Primary Human Skeletal Muscle Cells Derived from Obese Insulin-Resistant Participants. ACS OMEGA 2022; 7:42763-42773. [PMID: 36467954 PMCID: PMC9713796 DOI: 10.1021/acsomega.2c04473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 11/01/2022] [Indexed: 05/16/2023]
Abstract
Skeletal muscle insulin resistance is a major contributor to type-2 diabetes (T2D). Pioglitazone is a potent insulin sensitizer of peripheral tissues by targeting peroxisome proliferator-activated receptor gamma. Pioglitazone has been reported to protect skeletal muscle cells from lipotoxicity by promoting fatty acid mobilization and insulin signaling. However, it is unclear whether pioglitazone increases insulin sensitivity through changes in protein-protein interactions involving protein phosphatase 2A (PP2A). PP2A regulates various cell signaling pathways such as insulin signaling. Interaction of the catalytic subunit of PP2A (PP2Ac) with protein partners is required for PP2A specificity and activity. Little is known about PP2Ac partners in primary human skeletal muscle cells derived from lean insulin-sensitive (Lean) and obese insulin-resistant (OIR) participants. We utilized a proteomics method to identify PP2Ac interaction partners in skeletal muscle cells derived from Lean and OIR participants, with or without insulin and pioglitazone treatments. In this study, 216 PP2Ac interaction partners were identified. Furthermore, 26 PP2Ac partners exhibited significant differences in their interaction with PP2Ac upon insulin treatments between the two groups. Multiple pathways and molecular functions are significantly enriched for these 26 interaction partners, such as nonsense-mediated decay, metabolism of RNA, RNA binding, and protein binding. Interestingly, pioglitazone restored some of these abnormalities. These results provide differential PP2Ac complexes in Lean and OIR in response to insulin/pioglitazone, which may help understand molecular mechanisms underpinning insulin resistance and the insulin-sensitizing effects of pioglitazone treatments, providing multiple targets in various pathways to reverse insulin resistance and prevent and/or manage T2D with less drug side effects.
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Affiliation(s)
- Lana Alghanem
- Department
of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan48201, United States
| | - Xiangmin Zhang
- Department
of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan48201, United States
| | - Ruchi Jaiswal
- Department
of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan48201, United States
| | - Berhane Seyoum
- Division
of Endocrinology, Wayne State University School of Medicine, Wayne State University, Detroit, Michigan48201, United States
| | - Abdullah Mallisho
- Division
of Endocrinology, Wayne State University School of Medicine, Wayne State University, Detroit, Michigan48201, United States
| | - Zaher Msallaty
- Division
of Endocrinology, Wayne State University School of Medicine, Wayne State University, Detroit, Michigan48201, United States
| | - Zhengping Yi
- Department
of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan48201, United States
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4
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Singh D, Sharma S, Choudhary M, Kaur P, Budhwar V. Role of Plant Derived Products Through Exhilarating Peroxisome Proliferator Activated Receptor-γ (ppar-γ) in the Amelioration of Obesity Induced Insulin Resistance. CURRENT NUTRITION & FOOD SCIENCE 2022. [DOI: 10.2174/1573401318666220217111415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Abstract:
Insulin resistance is an elemental facet of the etiology of diabetes mellitus and the principal relating factor between obesity and diabetes. Oxidative stress, lipotoxicity, inflammation and receptor dysfunction are the underlying determinants of insulin resistance commencement in metabolic illnesses. ppar-γ is a nuclear transcription factor whose activation or inhibition directly influences insulin resistance and controls glucose and lipid homeostasis by modulating gene expression. Synthetic ligands of ppar-γ are therapeutically employed to counter the hyper-glycaemia associated with obesity and type 2 diabetes, but they possess severe side effects. In the modern era, bioactive phytochemicals have been employed in the drug development process and a considerable investigation has recently been initiated to analyze the ppar-γ activating ability of diverse phytochemicals. In this review, we outlined the role of phytochemicals in insulin resistance treatment through ppar-γ activation.
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Affiliation(s)
- Devender Singh
- Institute of Pharmaceutical Sciences, Kurukshetra University-136118, Haryana, India
| | - Sachin Sharma
- Institute of Pharmaceutical Sciences, Kurukshetra University-136118, Haryana, India
| | - Manjusha Choudhary
- Institute of Pharmaceutical Sciences, Kurukshetra University-136118, Haryana, India
| | - Prabhjeet Kaur
- Institute of Pharmaceutical Sciences, Kurukshetra University-136118, Haryana, India
| | - Vikas Budhwar
- Department of Pharmaceutical Scinces, Maharishi Dyanand University, Rohtak-124001, Haryana, India
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5
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Lund J, Krapf SA, Sistek M, Bakke HG, Bartesaghi S, Peng XR, Rustan AC, Thoresen GH, Kase ET. SENP2 is vital for optimal insulin signaling and insulin-stimulated glycogen synthesis in human skeletal muscle cells. CURRENT RESEARCH IN PHARMACOLOGY AND DRUG DISCOVERY 2021; 2:100061. [PMID: 34909683 PMCID: PMC8663970 DOI: 10.1016/j.crphar.2021.100061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 09/15/2021] [Accepted: 09/23/2021] [Indexed: 11/17/2022] Open
Abstract
Sentrin-specific protease (SENP) 2 has been suggested as a possible novel drug target for the treatment of obesity and type 2 diabetes mellitus after observations of a palmitate-induced increase in SENP2 that lead to increased fatty acid oxidation and improved insulin sensitivity in skeletal muscle cells from mice. However, no precedent research has examined the role of SENP2 in human skeletal muscle cells. In the present work, we have investigated the impact of SENP2 on fatty acid and glucose metabolism as well as insulin sensitivity in human skeletal muscle using cultured primary human myotubes. Acute (4 h) oleic acid oxidation was reduced in SENP2-knockdown (SENP2-KD) cells compared to control cells, with no difference in uptake. After prelabeling (24 h) with oleic acid, total lipid content and incorporation into triacylglycerol was decreased, while incorporation into other lipids, as well as complete oxidation and β-oxidation was increased in SENP2-KD cells. Basal glucose uptake (i.e., not under insulin-stimulated conditions) was higher in SENP2-KD cells, whereas oxidation was similar to control myotubes. Further, basal glycogen synthesis was not different in SENP2-KD myotubes, but both insulin-stimulated glycogen synthesis and AktSer473 phosphorylation was completely blunted in SENP2-KD cells. In conclusion, SENP2 plays an important role in fatty acid and glucose metabolism in human myotubes. Interestingly, it also appears to have a pivotal role in regulating myotube insulin sensitivity. Future studies should examine the role of SENP2 in regulation of insulin sensitivity in other tissues and in vivo, defining the potential for SENP2 as a drug target.
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Affiliation(s)
- Jenny Lund
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway
- Corresponding author. Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, P.O. Box 1068 Blindern, 0316 Oslo, Norway.
| | - Solveig A. Krapf
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway
| | - Medina Sistek
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway
| | - Hege G. Bakke
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway
| | - Stefano Bartesaghi
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM) BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Xiao-Rong Peng
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM) BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Arild C. Rustan
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway
| | - G. Hege Thoresen
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway
- Department of Pharmacology, Institute of Clinical Medicine, University of Oslo, Norway
| | - Eili T. Kase
- Section for Pharmacology and Pharmaceutical Biosciences, Department of Pharmacy, University of Oslo, Norway
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6
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Pires Mendes C, Postal BG, Silva Frederico MJ, Gonçalves Marques Elias R, Aiceles de Medeiros Pinto V, da Fonte Ramos C, Devantier Neuenfeldt P, Nunes RJ, Mena Barreto Silva FR. Synthesis of a novel glibenclamide-pioglitazone hybrid compound and its effects on glucose homeostasis in normal and insulin-resistant rats. Bioorg Chem 2021; 114:105157. [PMID: 34328855 DOI: 10.1016/j.bioorg.2021.105157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 04/19/2021] [Accepted: 07/05/2021] [Indexed: 12/30/2022]
Abstract
A new library of hybrid compounds that combine the functional parts of glibenclamide and pioglitazone was designed and developed. Compounds were screened for their antihyperglycemic effects on the glucose tolerance curve. This approach provided a single molecule that optimizes the pharmacological activities of two drugs used for the treatment of diabetes mellitus type 2 (DM2) and that have distinct biological activities, potentially minimizing the adverse effects of the original drugs. From a total of 15 compounds, 7 were evaluated in vivo; the compound 2; 4- [2- (2-phenyl-4-oxo-1,3-thiazolidin-3-yl) ethyl] benzene-1-sulfonamide (PTEBS) was selected to study its mechanism of action on glucose and lipid homeostasis in acute and chronic animal models related to DM2. PTEBS reduced glycemia and increased serum insulin in hyperglycemic rats, and elevated in vitro insulin production from isolated pancreatic islets. This compound increased the glycogen content in hepatic and muscular tissue. Moreover, PTEBS stimulated the uptake of glucose in soleus muscle through a signaling pathway similar to that of insulin, stimulating translocation and protein synthesis of glucose transporter 4 (GLUT4). PTEBS was effective in increasing insulin sensitivity in resistance rats by stimulating increased muscle glucose uptake, among other mechanisms. In addition, this compound reduced total triglycerides in a tolerance test to lipids and reduced advanced glycation end products (AGES), without altering lactate dehydrogenase (LDH) activity. Thus, we suggest that PTEBS may have similar effects to the respective prototypes, which may improve the therapeutic efficacy of these molecules and decrease adverse effects in the long-term.
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Affiliation(s)
- Camila Pires Mendes
- Universidade Federal de Santa Catarina, Departamento de Bioquímica - Centro de Ciências Biológicas, Campus Universitário, Trindade, CEP: 88040-900 - Florianópolis, SC, Brazil
| | - Bárbara Graziela Postal
- Universidade Federal de Santa Catarina, Departamento de Bioquímica - Centro de Ciências Biológicas, Campus Universitário, Trindade, CEP: 88040-900 - Florianópolis, SC, Brazil
| | - Marisa Jádna Silva Frederico
- Universidade Federal de Santa Catarina, Departamento de Bioquímica - Centro de Ciências Biológicas, Campus Universitário, Trindade, CEP: 88040-900 - Florianópolis, SC, Brazil; Universidade Federal do Ceará, Departamento de Farmacologia e Fisiologia, Faculdade de Medicina, Núcleo de Pesquisa e Desenvolvimento de Medicamentos, Rua Coronel Nunes de Melo, 1000 - Rodolfo Teófilo, Fortaleza, CE 60430-275, Brazil
| | - Rui Gonçalves Marques Elias
- Universidade Federal de Santa Catarina, Departamento de Bioquímica - Centro de Ciências Biológicas, Campus Universitário, Trindade, CEP: 88040-900 - Florianópolis, SC, Brazil; Universidade Estadual do Norte do Paraná - Centro de Ciências da Saúde, Jacarezinho, PR, Brazil
| | | | | | - Patrícia Devantier Neuenfeldt
- Universidade Federal de Santa Catarina, Departamento de Química, Centro de Ciências Físicas e Matemáticas, Campus Universitário, Trindade, CEP: 88040-900, Florianópolis, SC, Brazil; Instituto Federal Catarinense, IFC, Campus São Francisco do Sul, SC, Brazil
| | - Ricardo José Nunes
- Universidade Federal de Santa Catarina, Departamento de Química, Centro de Ciências Físicas e Matemáticas, Campus Universitário, Trindade, CEP: 88040-900, Florianópolis, SC, Brazil
| | - Fátima Regina Mena Barreto Silva
- Universidade Federal de Santa Catarina, Departamento de Bioquímica - Centro de Ciências Biológicas, Campus Universitário, Trindade, CEP: 88040-900 - Florianópolis, SC, Brazil.
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7
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Khasabova IA, Seybold VS, Simone DA. The role of PPARγ in chemotherapy-evoked pain. Neurosci Lett 2021; 753:135845. [PMID: 33774149 PMCID: PMC8089062 DOI: 10.1016/j.neulet.2021.135845] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 02/27/2021] [Accepted: 03/19/2021] [Indexed: 12/13/2022]
Abstract
Although millions of people are diagnosed with cancer each year, survival has never been greater thanks to early diagnosis and treatments. Powerful chemotherapeutic agents are highly toxic to cancer cells, but because they typically do not target cancer cells selectively, they are often toxic to other cells and produce a variety of side effects. In particular, many common chemotherapies damage the peripheral nervous system and produce neuropathy that includes a progressive degeneration of peripheral nerve fibers. Chemotherapy-induced peripheral neuropathy (CIPN) can affect all nerve fibers, but sensory neuropathies are the most common, initially affecting the distal extremities. Symptoms include impaired tactile sensitivity, tingling, numbness, paraesthesia, dysesthesia, and pain. Since neuropathic pain is difficult to manage, and because degenerated nerve fibers may not grow back and regain normal function, considerable research has focused on understanding how chemotherapy causes painful CIPN so it can be prevented. Due to the fact that both therapeutic and side effects of chemotherapy are primarily associated with the accumulation of reactive oxygen species (ROS) and oxidative stress, this review focuses on the activation of endogenous antioxidant pathways, especially PPARγ, in order to prevent the development of CIPN and associated pain. The use of synthetic and natural PPARγ agonists to prevent CIPN is discussed.
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Affiliation(s)
- Iryna A Khasabova
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, MN, 55455, United States
| | - Virginia S Seybold
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, MN, 55455, United States
| | - Donald A Simone
- Department of Diagnostic and Biological Sciences, University of Minnesota, School of Dentistry, Minneapolis, MN, 55455, United States.
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8
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Gilarevsky SR. [Clinical Efficacy and Mechanisms of Actions of the Glucagon-Like Peptide-1 Receptor Agonists in Patients with Type 2 Diabetes Mellitus and High Risk of Cardiovascular Diseases]. ACTA ACUST UNITED AC 2021; 61:66-72. [PMID: 33998411 DOI: 10.18087/cardio.2021.4.n1549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 03/11/2021] [Indexed: 11/18/2022]
Abstract
The article discusses issues of reducing the risk for cardiovascular diseases (CVDs) in patients with type 2 diabetes mellitus during the treatment with modern hypoglycemic drugs, specifically glucagon-like peptide-1 receptor agonists.
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Affiliation(s)
- S R Gilarevsky
- Russian Medical Academy of Continuing Professional Education of the Ministry of Health of the Russian Federation, Moscow
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9
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Sirt1-PPARS Cross-Talk in Complex Metabolic Diseases and Inherited Disorders of the One Carbon Metabolism. Cells 2020; 9:cells9081882. [PMID: 32796716 PMCID: PMC7465293 DOI: 10.3390/cells9081882] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/07/2020] [Accepted: 08/07/2020] [Indexed: 12/15/2022] Open
Abstract
Sirtuin1 (Sirt1) has a NAD (+) binding domain and modulates the acetylation status of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) and Fork Head Box O1 transcription factor (Foxo1) according to the nutritional status. Sirt1 is decreased in obese patients and increased in weight loss. Its decreased expression explains part of the pathomechanisms of the metabolic syndrome, diabetes mellitus type 2 (DT2), cardiovascular diseases and nonalcoholic liver disease. Sirt1 plays an important role in the differentiation of adipocytes and in insulin signaling regulated by Foxo1 and phosphatidylinositol 3′-kinase (PI3K) signaling. Its overexpression attenuates inflammation and macrophage infiltration induced by a high fat diet. Its decreased expression plays a prominent role in the heart, liver and brain of rat as manifestations of fetal programming produced by deficit in vitamin B12 and folate during pregnancy and lactation through imbalanced methylation/acetylation of PGC1α and altered expression and methylation of nuclear receptors. The decreased expression of Sirt1 produced by impaired cellular availability of vitamin B12 results from endoplasmic reticulum stress through subcellular mislocalization of ELAVL1/HuR protein that shuttles Sirt1 mRNA between the nucleus and cytoplasm. Preclinical and clinical studies of Sirt1 agonists have produced contrasted results in the treatment of the metabolic syndrome. A preclinical study has produced promising results in the treatment of inherited disorders of vitamin B12 metabolism.
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10
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Ferreira MDR, Oliva ME, Aiassa V, D'Alessandro ME. Salvia hispanica L. (chia) seed improves skeletal muscle lipotoxicity and insulin sensitivity in rats fed a sucrose-rich diet by modulating intramuscular lipid metabolism. J Funct Foods 2020. [DOI: 10.1016/j.jff.2019.103775] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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11
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de Mendonça M, de Sousa É, da Paixão AO, Araújo Dos Santos B, Roveratti Spagnol A, Murata GM, Araújo HN, Imamura de Lima T, Passos Simões Fróes Guimarães DS, Silveira LR, Rodrigues AC. MicroRNA miR-222 mediates pioglitazone beneficial effects on skeletal muscle of diet-induced obese mice. Mol Cell Endocrinol 2020; 501:110661. [PMID: 31770568 DOI: 10.1016/j.mce.2019.110661] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 11/19/2019] [Accepted: 11/19/2019] [Indexed: 01/23/2023]
Abstract
Pioglitazone belongs to the class of drugs thiazolidinediones (TZDs) and is an oral hypoglycemic drug, used in the treatment of type 2 diabetes, which improves insulin sensitivity in target tissues. Adipose tissue is the main target of pioglitazone, a PPARg and PPARa agonist; however, studies also point to skeletal muscle as a target. Non-PPAR targets of TZDs have been described, thus we aimed to study the direct effects of pioglitazone on skeletal muscle and the possible role of microRNAs as targets of this drug. Pioglitazone treatment of obese mice increased insulin-mediated glucose transport as a result of increased fatty acid oxidation and mitochondrial activity. PPARg blockage by treatment with GW9662 nullified pioglitazone's effect on systemic and muscle insulin sensitivity and citrate synthase activity of obese mice. After eight weeks of high-fat diet, miR-221-3p expression in soleus muscle was similar among the groups and miR-23b-3p and miR-222-3p were up-regulated in obese mice compared to the control group, and treatment with pioglitazone was able to reverse this condition. In vitro studies in C2C12 cells suggest that inhibition of miR-222-3p protects C2C12 cells from insulin resistance and increased non-mitochondrial respiration induced by palmitate. Together, these data demonstrate a role of pioglitazone in the downregulation of microRNAs that is not dependent on PPARg. Moreover, miR-222 may be a novel PPARg-independent mechanism through which pioglitazone improves insulin sensitivity in skeletal muscle.
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MESH Headings
- Adipose Tissue/drug effects
- Adipose Tissue/metabolism
- Animals
- Blood Glucose/drug effects
- Blood Glucose/metabolism
- Diabetes Mellitus, Experimental/drug therapy
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Type 2/drug therapy
- Diabetes Mellitus, Type 2/metabolism
- Diet, High-Fat/adverse effects
- Disease Models, Animal
- Down-Regulation/drug effects
- Glucose/metabolism
- Glucose Tolerance Test
- Hypoglycemic Agents
- Insulin/metabolism
- Insulin Resistance/physiology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Obese
- MicroRNAs/metabolism
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Obesity/drug therapy
- Obesity/metabolism
- PPAR alpha/metabolism
- PPAR gamma/metabolism
- Palmitates/pharmacology
- Pioglitazone/pharmacology
- Thiazolidinediones/pharmacology
- Up-Regulation/drug effects
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Affiliation(s)
| | - Érica de Sousa
- Department of Pharmacology, University of Sao Paulo, Sao Paulo, SP, Brazil
| | - Ailma O da Paixão
- Department of Pharmacology, University of Sao Paulo, Sao Paulo, SP, Brazil
| | | | | | - Gilson M Murata
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil
| | - Hygor N Araújo
- Obesity and Comorbidities Research Center, Campinas, Sao Paulo, Brazil; Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Tanes Imamura de Lima
- Obesity and Comorbidities Research Center, Campinas, Sao Paulo, Brazil; Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Dimitrius Santiago Passos Simões Fróes Guimarães
- Obesity and Comorbidities Research Center, Campinas, Sao Paulo, Brazil; Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Leonardo R Silveira
- Obesity and Comorbidities Research Center, Campinas, Sao Paulo, Brazil; Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Alice C Rodrigues
- Department of Pharmacology, University of Sao Paulo, Sao Paulo, SP, Brazil.
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12
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Jo YH, Peng DQ, Kim WS, Kim SJ, Kim NY, Kim SH, Ghassemi Nejad J, Lee JS, Lee HG. The effects of vitamin A supplementation during late-stage pregnancy on longissimus dorsi muscle tissue development, birth traits, and growth performance in postnatal Korean native calves. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2019; 33:742-752. [PMID: 32054186 PMCID: PMC7206403 DOI: 10.5713/ajas.19.0413] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 11/18/2019] [Indexed: 12/12/2022]
Abstract
OBJECTIVE This study investigated the effects of vitamin A (VA) supplementation during late-stage pregnancy on longissimus dorsi muscle tissue development, birth traits, and growth performance of postnatal Korean native calves. METHODS In the preliminary experiment, twenty-six pregnant cattle (initial body weight [BW] = 319 kg (standard deviation [SD] = 30.1; 1st parity) were randomly assigned to the control and treatment groups. The treatment group received VA supplementation at 24,000 IU/d from gestational day 225 until delivery. In the main experiment, twelve pregnant cattle (initial BW = 317 kg [SD = 31.3]; 1st parity) were treated with VA supplementation at 24,000 IU/d (gestational days 150 to 225) and at 78,000 IU/d (gestational day 225 until delivery). Serum VA levels were analyzed in pregnant cattle, and the growth performance, gene expression, and serum VA levels were analyzed in the offspring. RESULTS Serum VA levels in pregnant cattle decreased the late gestation in both experiments (p<0.001). In the main experiment, pregnant cattle at parturition and offspring at birth in the treatment group had higher serum VA levels than those in the control group (p<0.05). In the treatment groups, an increased birth weight was observed in the main experimental group (p = 0.022), and a tendency (p = 0.088) toward an increased birth weight was observed in the preliminary experimental group. However, no differences were observed in the feed intake, average daily gain, gain-to-feed ratio, or BW of 31-day-old calves. Gene expression was analyzed in longissimus dorsi muscles of 31-day-old calves. VA supplementation in pregnant cattle stimulated postnatal muscle development in offspring by elevating myogenic factor 5 (MYF5), MYF6, and myoblast determination levels (p<0.05). Moreover, preadipocyte-related marker genes such as extracellular signal-regulated kinase 2 and krüppel-like factor 2 were higher in the treatment group than in the control group (p<0.05). CONCLUSION VA supplementation (78,000 IU/d) in late-stage pregnant cattle maintained serum VA levels. In addition, 78,000 IU/d VA supplementation increased the birth weight and expression of genes related to muscle and preadipocyte development in offspring. Overall, 78,000 IU/d VA supplementation in pregnant cattle is beneficial to newborn calves.
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Affiliation(s)
- Yong Ho Jo
- Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea.,Team of an Educational Program for Specialists in Global Animal Science, Brain Korea 21 Plus, Konkuk University, Seoul 05029, Korea
| | - Dong Qiao Peng
- Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea.,Team of an Educational Program for Specialists in Global Animal Science, Brain Korea 21 Plus, Konkuk University, Seoul 05029, Korea
| | - Won Seob Kim
- Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea.,Team of an Educational Program for Specialists in Global Animal Science, Brain Korea 21 Plus, Konkuk University, Seoul 05029, Korea
| | - Seong Jin Kim
- Asia Pacific Ruminant Institute, Icheon 467814, Korea
| | - Na Yeon Kim
- Asia Pacific Ruminant Institute, Icheon 467814, Korea
| | - Sung Hak Kim
- Department of Animal Science, Chonnam National University, Gwangju 61186, Korea
| | - Jalil Ghassemi Nejad
- Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea.,Team of an Educational Program for Specialists in Global Animal Science, Brain Korea 21 Plus, Konkuk University, Seoul 05029, Korea
| | - Jae Sung Lee
- Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea
| | - Hong Gu Lee
- Department of Animal Science and Technology, Konkuk University, Seoul 05029, Korea.,Team of an Educational Program for Specialists in Global Animal Science, Brain Korea 21 Plus, Konkuk University, Seoul 05029, Korea
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Kim SM, Jung JI, Chai C, Imm JY. Characteristics and Glucose Uptake Promoting Effect of Chrysin-Loaded Phytosomes Prepared with Different Phospholipid Matrices. Nutrients 2019; 11:E2549. [PMID: 31652637 PMCID: PMC6835247 DOI: 10.3390/nu11102549] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 10/18/2019] [Accepted: 10/21/2019] [Indexed: 12/16/2022] Open
Abstract
Chrysin-loaded phytosomes (CP) were prepared using either soya phosphatidylcholine (SPC) or egg phospholipid (EPL) by the solvent evaporation method. Different phospholipid matrices resulted in significant differences in size, mechanical property and solubility of the CP. The most stable CP was obtained with EPL at a molar ratio of 1:3 (chrysin: EPL, CEP-1:3). CEP-1:3 displayed an average size of 117 nm with uniform size distribution (polydispersity index: 0.30) and zeta potential of -31 mV. A significantly greater elastic modulus of CEP-1:3 (2.7-fold) indicated tighter packing and strong molecular bonding than those of CP prepared with SPC (CSP-1:3). X-ray diffraction and Fourier transform infrared spectroscopic analysis of CEP-1:3 confirmed molecular complexation. CEP-1:3 displayed a greater glucose uptake promoting effect than free chrysin and CSP-1:3 in muscle cells by stimulating gene expression of peroxisome proliferator-activated receptor γ and glucose transporter type 4. The results of the present study suggest that the phospholipid matrix used for the preparation of phytosomes critically influences their performance.
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Affiliation(s)
- Seong-Min Kim
- Department of Foods and Nutrition, Kookmin University, Seoul 02707, Korea.
| | - Jae-In Jung
- Department of Foods and Nutrition, Kookmin University, Seoul 02707, Korea.
| | - Changhoon Chai
- Department of Applied Animal Science, Kangwon National University, Chuncheon 24341, Korea.
| | - Jee-Young Imm
- Department of Foods and Nutrition, Kookmin University, Seoul 02707, Korea.
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The Zinc Transporter Zip7 Is Downregulated in Skeletal Muscle of Insulin-Resistant Cells and in Mice Fed a High-Fat Diet. Cells 2019; 8:cells8070663. [PMID: 31266232 PMCID: PMC6678147 DOI: 10.3390/cells8070663] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 06/27/2019] [Accepted: 06/28/2019] [Indexed: 12/14/2022] Open
Abstract
Background: The zinc transporter Zip7 modulates zinc flux and controls cell signaling molecules associated with glucose metabolism in skeletal muscle. The present study evaluated the role of Zip7 in cell signaling pathways involved in insulin-resistant skeletal muscle and mice fed a high-fat diet. Methods: Insulin-resistant skeletal muscle cells were prepared by treatment with an inhibitor of the insulin receptor, HNMPA-(AM)3 or palmitate, and Zip7 was analyzed along with pAkt, pTyrosine and Glut4. Similarly, mice fed normal chow (NC) or a high-fat diet (HFD) were also analyzed for protein expression of Glut4 and Zip7. An overexpression system for Zip7 was utilized to determine the action of this zinc transporter on several genes implicated in insulin signaling and glucose control. Results: We identified that Zip7 is upregulated by glucose in normal skeletal muscle cells and downregulated in insulin-resistant skeletal muscle. We also observed (as expected) a decrease in pAkt and Glut4 in the insulin-resistant skeletal muscle cells. The overexpression of Zip7 in skeletal muscle cells led to the modulation of key genes involved in the insulin signaling axis and glucose metabolism including Akt3, Dok2, Fos, Hras, Kras, Nos2, Pck2, and Pparg. In an in vivo mouse model, we identified a reduction in Glut4 and Zip7 in the skeletal muscle of mice fed a HFD compared to NC controls. Conclusions: These data suggest that Zip7 plays a role in skeletal muscle insulin signaling and is downregulated in an insulin-resistant, and HFD state. Understanding the molecular mechanisms of Zip7 action will provide novel opportunities to target this transporter therapeutically for the treatment of insulin resistance and type 2 diabetes.
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15
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Kulabas SS, Ipek H, Tufekci AR, Arslan S, Demirtas I, Ekren R, Sezerman U, Tumer TB. Ameliorative potential of Lavandula stoechas in metabolic syndrome via multitarget interactions. JOURNAL OF ETHNOPHARMACOLOGY 2018; 223:88-98. [PMID: 29729383 DOI: 10.1016/j.jep.2018.04.043] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 04/19/2018] [Accepted: 04/28/2018] [Indexed: 06/08/2023]
Abstract
ETHNOPHARMACOLOGICAL IMPORTANCE Decoction and infusion prepared from aerial parts of Lavandula stoechas L. (L. stoechas) have been traditionally used as remedy against several components of metabolic syndrome (MetS) and associated disorders including type II diabetes and cardiovascular diseases by Anatolian people. AIM OF THE STUDY The aim is to elucidate the potential ameliorative effects of L. stoechas aqueous extracts on insulin resistance and inflammation models through multitarget in vitro approaches and also to elucidate mechanism of action by analyzing transcriptional and metabolic responses. MATERIALS AND METHODS An aqueous extract was prepared and fractionated to give rise to ethyl acetate (EE) and butanol (BE) extracts. The anti-insulin resistance effects of BE and EE were evaluated on palmitate induced insulin resistance model of H4IIE, C2C12 and 3T3L1 cells by using several metabolic parameters. Specifically, whole genome transcriptome analysis was performed by using microarray over 55.000 genes in control, insulin resistant and EE (25 µg/mL) treated insulin resistant H4IIE cells. Anti-inflammatory effects of both extracts were analyzed in LPS-stimulated RAW264.7 macrophages. RESULTS Both EE and BE at low doses (25-50 µg/mL) significantly decreased hepatic gluconeogenesis in H4IIE cell line by suppressing the expression of PEPCK and G6Pase. In C2C12 myotubes, both extracts increased the insulin stimulated glucose uptake more effectively than metformin. Both extracts decreased the isoproterenol induced lipolysis in 3T3L1 cell line. Moreover, they also effectively increased the expression of lipoprotein lipase protein level in insulin resistant myotubes at low doses. EE increased the protein level of PPARγ and stimulated the activation AKT in insulin resistant H4IIE and C2C12 cell lines. The results obtained from biochemical assays, mRNA/protein studies and whole genome transcriptome analyses were found to be complementary and provided support for the hypothesis that EE might be biologically active against insulin resistance and act through the inhibition of liver gluconeogenesis and AKT activation. Besides, LPS induced inflammation in RAW264.7 macrophages was mainly inhibited by EE through suppression of iNOS/NO signaling, IL1β and COX-2 genes. HPLC-TOF/MS analysis of EE of L. stoechas mainly resulted in caffeic acid, apigenin, luteolin, rosmarinic acid and its methyl ester, 4-hydroxybenzoic acid, vanillic acid, ferrulic acid and salicylic acid. CONCLUSION Data suggest that EE of L. stoechas contains phytochemicals that can be effective in the treatment/prevention of insulin resistance and inflammation. These results validate the traditional use of L. stoechas in Anatolia against several metabolic disorders including metabolic syndrome.
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Affiliation(s)
- S S Kulabas
- Graduate Program of Biology, Institute of Natural and Applied Sciences, Çanakkale Onsekiz Mart University, 17100 Çanakkale, Turkey
| | - H Ipek
- Graduate Program of Bioengineering, Institute of Natural and Applied Sciences, Çanakkale Onsekiz Mart University, 17100 Çanakkale, Turkey
| | - A R Tufekci
- Department of Chemistry, Faculty of Sciences, Çankırı Karatekin University 18200 Çankırı Turkey
| | - S Arslan
- Department of Biology, Faculty of Art and Science, Pamukkale University, 20160 Denizli, Turkey
| | - I Demirtas
- Department of Chemistry, Faculty of Sciences, Çankırı Karatekin University 18200 Çankırı Turkey
| | - R Ekren
- Graduate Program of Medical Biotechnology, Institute of Health Sciences, Acıbadem Mehmet Ali Aydınlar University, 34752 İstanbul, Turkey
| | - U Sezerman
- Department of Biostatistics and Medical Informatics, Institute of Health Sciences, Acıbadem Mehmet Ali Aydınlar University, 34752 İstanbul, Turkey
| | - T B Tumer
- Department of Molecular Biology and Genetics, Faculty of Art and Science, Çanakkale Onsekiz Mart University, 17100 Çanakkale, Turkey.
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16
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Capel F, Geloen A, Vaysse C, Pineau G, Demaison L, Chardigny JM, Michalski MC, Malpuech-Brugère C. Rapeseed oil fortified with micronutrients can reduce glucose intolerance during a high fat challenge in rats. Nutr Metab (Lond) 2018; 15:22. [PMID: 29568317 PMCID: PMC5859643 DOI: 10.1186/s12986-018-0259-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 03/12/2018] [Indexed: 12/13/2022] Open
Abstract
Background Better choices of dietary lipid sources and substitution of refined by fortified oils could reduce the intake of saturated fatty acids (FA) and increase the intake of omega 3 FA concomitantly to healthy bioactive compounds. Methods The development of obesity and metabolic disturbances was explored in rats fed during 11 weeks with a high fat diet (HFD) in which the amount of saturated and polyunsaturated FA was respectively reduced and increased, using rapeseed oil as lipid source. This oil was used in a refined form (R) or fortified (10 fold increase in concentration) with endogenous micronutrients (coenzyme Q10 + tocopherol only (RF) only and also with canolol (RFC)). The effect of substituting palm by rapeseed oil was analysed using a student t test, oil fortification was analysed using ANOVA statistical test. Results Despite a similar weight gain, diets R, RF and RFC improved glucose tolerance (+ 10%) of the rats compared to a standard HFD with palm and sunflower oils as lipid source. Plasma glucose was lowered in RF and RFC groups (- 15 and 23% respectively), although triacylglycerol level was only reduced in group RFC (- 33%) compared to R. The fortification with canolol promoted the activation of Akt and AMP-activated protein kinase (AMPK) in skeletal muscle and subcutaneous adipose tissue respectively. Canolol supplementation also led to reduce p38 MAPK activation in skeletal muscle. Conclusions This study suggests that the presence of endogenous micronutrients in rapeseed oil promotes cellular adaptations to reverse glucose intolerance and improve the metabolism of insulin sensitive tissues.
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Affiliation(s)
- Frederic Capel
- 1INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Université Clermont Auvergne, 58 rue Montalembert - BP 321, F-63000 Clermont-Ferrand, France
| | - Alain Geloen
- 2Laboratoire CarMeN, INRA UMR1397, INSERM U1060, Univ-Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, IMBL, F-69621 Villeurbanne, France
| | - Carole Vaysse
- 3ITERG-ENMS, Université de Bordeaux, rue Léo Saignat, 33076 Bordeaux Cedex, France
| | - Gaelle Pineau
- 2Laboratoire CarMeN, INRA UMR1397, INSERM U1060, Univ-Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, IMBL, F-69621 Villeurbanne, France
| | - Luc Demaison
- 1INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Université Clermont Auvergne, 58 rue Montalembert - BP 321, F-63000 Clermont-Ferrand, France
| | - Jean-Michel Chardigny
- 1INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Université Clermont Auvergne, 58 rue Montalembert - BP 321, F-63000 Clermont-Ferrand, France.,Present address : Centre de Recherche INRA Bourgogne Franche Comté Bâtiment Le Magnen, 17 rue Sully BP 86510, 21065 DIJON Cedex, France
| | - Marie-Caroline Michalski
- 2Laboratoire CarMeN, INRA UMR1397, INSERM U1060, Univ-Lyon, Université Claude Bernard Lyon 1, INSA-Lyon, IMBL, F-69621 Villeurbanne, France
| | - Corinne Malpuech-Brugère
- 1INRA, UNH, Unité de Nutrition Humaine, CRNH Auvergne, Université Clermont Auvergne, 58 rue Montalembert - BP 321, F-63000 Clermont-Ferrand, France
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Roca-Saavedra P, Mariño-Lorenzo P, Miranda J, Porto-Arias J, Lamas A, Vazquez B, Franco C, Cepeda A. Phytanic acid consumption and human health, risks, benefits and future trends: A review. Food Chem 2017; 221:237-247. [DOI: 10.1016/j.foodchem.2016.10.074] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 09/29/2016] [Accepted: 10/18/2016] [Indexed: 12/18/2022]
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18
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PPARγ regulates inflammatory reaction by inhibiting the MAPK/NF-κB pathway in C2C12 skeletal muscle cells. J Physiol Biochem 2016; 73:49-57. [DOI: 10.1007/s13105-016-0523-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Accepted: 09/21/2016] [Indexed: 11/26/2022]
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19
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Manzano M, Giron MD, Vilchez JD, Sevillano N, El-Azem N, Rueda R, Salto R, Lopez-Pedrosa JM. Apple polyphenol extract improves insulin sensitivity in vitro and in vivo in animal models of insulin resistance. Nutr Metab (Lond) 2016; 13:32. [PMID: 27141227 PMCID: PMC4852413 DOI: 10.1186/s12986-016-0088-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 04/19/2016] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Apple polyphenols could represent a novel nutritional approach in the management and control of blood glucose, especially in type 2 diabetics. The aim of this study was to test the therapeutic potential of an apple polyphenol extract (APE) in an insulin-resistant rat model and to determine the molecular basis of insulin sensitivity action in skeletal muscle cells. METHODS Acute effect of APE on the postprandial hyperglycemic response was assayed in 15 week old obese Zucker rats (OZR), by using a meal tolerance test (MTT). The ability of APE to improve whole peripheral insulin sensitivity was also assayed in a chronic study by using the euglycemic-hyperinsulinemic clamp technique. To elucidate the molecular mechanisms, rat L6 myotubes were used. Glucose uptake was measured by using 2-[3H]-Deoxy-Glucose (2-DG) and specific inhibitors, as well as phosphorylation status of key kinases, were used to determine the implicated signaling pathway. RESULTS In vivo study showed that nutritional intervention with APE induced an increase of insulin sensitivity with an increase of glucose infusion rate (GIR) of 45 %. Additionally, in vitro results showed a synergistic effect between APE and insulin as well as increased glucose uptake through GLUT4 translocation in muscle cells. This translocation was mediated by phosphatydil inositol 3-kinase (PI3K) and peroxisome proliferator-activated receptor-gamma (PPARγ) signaling pathways. CONCLUSIONS As a whole, this study describes the mechanisms involved in the insulin sensitizing effect of APE, which could be considered a promising ingredient for inclusion in nutritional products focused on the management of chronic diseases such as diabetes.
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Affiliation(s)
- Manuel Manzano
- Strategic R&D, Abbott Nutrition Research & Development, Camino de Purchil, 68, Granada, Spain
| | - María D Giron
- Biochemistry and Molecular Biology II, University of Granada, Granada, Spain
| | - José D Vilchez
- Biochemistry and Molecular Biology II, University of Granada, Granada, Spain
| | - Natalia Sevillano
- Biochemistry and Molecular Biology II, University of Granada, Granada, Spain
| | - Nuri El-Azem
- Strategic R&D, Abbott Nutrition Research & Development, Camino de Purchil, 68, Granada, Spain
| | - Ricardo Rueda
- Strategic R&D, Abbott Nutrition Research & Development, Camino de Purchil, 68, Granada, Spain
| | - Rafael Salto
- Biochemistry and Molecular Biology II, University of Granada, Granada, Spain
| | - Jose M Lopez-Pedrosa
- Strategic R&D, Abbott Nutrition Research & Development, Camino de Purchil, 68, Granada, Spain
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Fahri FT, Clarke IJ, Pethick DW, Warner RD, Dunshea FR. Rosiglitazone maleate increases weight gain and body fat content in growing lambs. ANIMAL PRODUCTION SCIENCE 2016. [DOI: 10.1071/an14885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Thiazolidinediones (TZD) are synthetic orally active peroxisome proliferator-activated receptor γ ligands used in the treatment of diabetes mellitus. The peroxisome proliferator-activated receptor γ gene plays an important role in regulating fat cell development, energy balance, and lipid metabolism in adipose and skeletal muscle tissue. There is interest in pharmacologic or nutritional means that may complement genetic techniques to improve growth and carcass composition of lambs and the major aim of the present study was to determine whether TZD impact on growth performance and meat quality of growing lambs. An initial study with four cross-bred lambs confirmed that rosiglitazone maleate is absorbed after oral dosing for 7 days. A second study was conducted with 30 cross-bred lambs to investigate the effects of sex (ewe vs wether) and dose of orally administered rosiglitazone maleate (0, 8 and 24 mg/day) for 55 days on growth performance, body composition, plasma metabolites and insulin and meat quality. Feed intake tended to increase linearly with dose of TZD (1521, 1816 and 1878 g/day for 0, 8 and 24 mg/day, P = 0.07) over the entire study, and particularly during the second half of the study (P < 0.05). There were both linear (P = 0.05) and quadratic (P = 0.04) responses in average daily gain to TZD (215, 270 and 261 g/day) with the quadratic response being most pronounced over the second half of the study (P = 0.004). As a result of the increased feed intake back fat (9.4, 11.1 and 13.5 mm, P < 0.001) and carcass fat (27.5%, 29.2% and 30.1%, P = 0.05) increased linearly with dose of TZD. However, there was no effect of TZD on internal fat depots. Plasma non-esterified acid concentrations increased linearly (0.37, 0.39 and 0.41 mM, P = 0.01) whereas plasma insulin concentrations (23.2, 26.9 and 20.9 mU/L, P = 0.05) and the homeostatic model assessment (6.82, 7.73 and 5.98, P = 0.05) exhibited quadratic responses to TZD. There were no significant effects of TZD on muscle pH, temperature or colour although muscle pH was higher at any temperature in ewes (+ 0.05 of a pH unit, P = 0.036) than in wethers. In conclusion, these data confirm that rosiglitazone maleate was rapidly absorbed from the digestive tract of growing ruminant lambs and was metabolically active. Oral TZD treatment appeared to mitigate against the inhibitory effect of carcass fatness on feed intake but the additional energy consumed was in turn deposited as fat.
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Liao HY, Sun MF, Lin JG, Chang SL, Lee YC. Electroacupuncture plus metformin lowers glucose levels and facilitates insulin sensitivity by activating MAPK in steroid-induced insulin-resistant rats. Acupunct Med 2015; 33:388-94. [PMID: 26025384 DOI: 10.1136/acupmed-2014-010724] [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] [Accepted: 05/11/2015] [Indexed: 01/23/2023]
Abstract
BACKGROUND Type 2 diabetes mellitus is the predominant form of diabetes. Although metformin is the preferred first-line drug for treatment of the disease, it is associated with a risk of secondary failure. Electroacupuncture (EA) can enhance insulin sensitivity and reduce blood glucose levels. OBJECTIVES To examine, in an animal study, whether EA combined with metformin (EA-metformin) results in a better glucose-lowering effect and greater insulin sensitivity than metformin alone in steroid-induced insulin-resistant rats. METHODS Adult Wistar rats were injected with dexamethasone to induce diabetes and subsequently treated with EA plus metformin or metformin alone. Variations in plasma glucose, plasma insulin, and plasma free fatty acid levels were studied at the midpoint and end of the experimental course. Insulin receptor substrate 1 (IRS-1) and peroxisome proliferator-activated receptor γ (PPAR-γ), which are associated with glucose transporter type 4 (GLUT4) translocation, and mitogen-activated protein kinase (MAPK), which is related to GLUT4 activation, were measured after EA treatment. RESULTS We found that EA-metformin resulted in a better glucose-lowering effect, greater insulin sensitivity, lower plasma free fatty acid levels and higher levels of MAPK than metformin alone (p<0.05). There were no significant differences between treatment groups in expression of IRS-1 or PPAR-γ. CONCLUSIONS The glucose-lowering effect and increased insulin sensitivity associated with EA-metformin administration is governed, at least in part, by its ability to stimulate the activation of GLUT4 via upregulation of MAPK expression.
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Affiliation(s)
- Hsien-Yin Liao
- Department of Acupuncture, China Medical University Hospital, Taichung, Taiwan School of Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Mao-Feng Sun
- Department of Acupuncture, China Medical University Hospital, Taichung, Taiwan School of Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Jaung-Geng Lin
- School of Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Shih-Liang Chang
- School of Chinese Medicine, China Medical University, Taichung, Taiwan Department of Medicinal Botanicals and Health Applications, Da-Yeh University, Changhua, Taiwan
| | - Yu-Chen Lee
- Department of Acupuncture, China Medical University Hospital, Taichung, Taiwan Graduate Institute of Acupuncture Science, China Medical University, Taichung, Taiwan
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23
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Henagan TM, Stefanska B, Fang Z, Navard AM, Ye J, Lenard NR, Devarshi PP. Sodium butyrate epigenetically modulates high-fat diet-induced skeletal muscle mitochondrial adaptation, obesity and insulin resistance through nucleosome positioning. Br J Pharmacol 2015; 172:2782-98. [PMID: 25559882 DOI: 10.1111/bph.13058] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 11/24/2014] [Accepted: 12/15/2014] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND AND PURPOSE Sodium butyrate (NaB), an epigenetic modifier, is effective in promoting insulin sensitivity. The specific genomic loci and mechanisms underlying epigenetically induced obesity and insulin resistance and the targets of NaB are not fully understood. EXPERIMENTAL APPROACH The anti-diabetic and anti-obesity effects of NaB treatment were measured by comparing phenotypes and physiologies of C57BL/6J mice fed a low-fat diet (LF), high-fat diet (HF) or high-fat diet plus NaB (HF + NaB) for 10 weeks. We determined a possible mechanism of NaB action through induction of beneficial skeletal muscle mitochondrial adaptations and applied microccocal nuclease digestion with sequencing (MNase-seq) to assess whole genome differences in nucleosome occupancy or positioning and to identify associated epigenetic targets of NaB. KEY RESULTS NaB prevented HF diet-induced increases in body weight and adiposity without altering food intake or energy expenditure, improved insulin sensitivity as measured by glucose and insulin tolerance tests, and decreased respiratory exchange ratio. In skeletal muscle, NaB increased the percentage of type 1 fibres, improved acylcarnitine profiles as measured by metabolomics and produced a chromatin structure, determined by MNase-seq, similar to that seen in LF. Targeted analysis of representative nuclear-encoded mitochondrial genes showed specific repositioning of the -1 nucleosome in association with altered gene expression. CONCLUSIONS AND IMPLICATIONS NaB treatment may be an effective pharmacological approach for type 2 diabetes and obesity by inducing -1 nucleosome repositioning within nuclear-encoded mitochondrial genes, causing skeletal muscle mitochondrial adaptations that result in more complete β-oxidation and a lean, insulin sensitive phenotype.
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Affiliation(s)
- Tara M Henagan
- Department of Nutrition Science, Purdue University, West Lafayette, IN, USA
| | - Barbara Stefanska
- Department of Nutrition Science, Purdue University, West Lafayette, IN, USA
| | - Zhide Fang
- Biostatistics Program, School of Public Health, Louisiana State University Health Sciences Center, New Orleans, LA, USA
| | - Alexandra M Navard
- Neurosignaling Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, USA
| | - Jianping Ye
- Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA, USA
| | - Natalie R Lenard
- Department of Sciences, Our Lady of the Lake College, Baton Rouge, LA, USA
| | - Prasad P Devarshi
- Department of Nutrition Science, Purdue University, West Lafayette, IN, USA
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Abstract
Peroxisome proliferator-activated receptor gamma (PPARγ) has been the focus of intense research because ligands for this receptor have emerged as potent insulin sensitizers used in the treatment of type 2 diabetes. There have been described three PPAR isotypes α, δ and γ which have an integrated role in controlling the expression of genes playing key roles in the storage and mobilization of lipids, in glucose metabolism, in morphogenesis and inflammatory response. Recent advances include the discovery of novel genes that are regulated by PPARγ, which helps to explain how activation of this adipocyte predominant transcription factor regulates glucose and lipid homeostasis. Increased levels of circulating free fatty acids and lipid accumulation in non-adipose tissue have been implicated in the development of insulin resistance. This situation is improved by PPARγ ligands, which promotes fatty acid storage in fat deposits and regulates the expression of adipocyte-secreted hormones that impacts on glucose homeostasis. So the net result of the pleiotropic effects of PPARγ ligands is improvement of insulin sensitivity. This review highlights the roles that PPAR gamma play in the regulation of gene expression of multiple diseases including obesity, diabetes and cancer and highlights the gene isolation transformation role. Further studies are needed for the transformation of PPAR gamma gene in plants and evaluate in animals for the treatment of type 2 diabetes.
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Affiliation(s)
- C Janani
- Department of Plant Science, Bharathidasan University, Tiruchirapalli 620 024, India
| | - B D Ranjitha Kumari
- Department of Plant Science, Bharathidasan University, Tiruchirapalli 620 024, India.
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Kawabata F, Mizushige T, Uozumi K, Hayamizu K, Han L, Tsuji T, Kishida T. Fish protein intake induces fast-muscle hypertrophy and reduces liver lipids and serum glucose levels in rats. Biosci Biotechnol Biochem 2014; 79:109-16. [PMID: 25198797 DOI: 10.1080/09168451.2014.951025] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In our previous study, fish protein was proven to reduce serum lipids and body fat accumulation by skeletal muscle hypertrophy and enhancing basal energy expenditure in rats. In the present study, we examined the precise effects of fish protein intake on different skeletal muscle fiber types and metabolic gene expression of the muscle. Fish protein increased fast-twitch muscle weight, reduced liver triglycerides and serum glucose levels, compared with the casein diet after 6 or 8 weeks of feeding. Furthermore, fish protein upregulated the gene expressions of a fast-twitch muscle-type marker and a glucose transporter in the muscle. These results suggest that fish protein induces fast-muscle hypertrophy, and the enhancement of basal energy expenditure by muscle hypertrophy and the increase in muscle glucose uptake reduced liver lipids and serum glucose levels. The present results also imply that fish protein intake causes a slow-to-fast shift in muscle fiber type.
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Affiliation(s)
- Fuminori Kawabata
- a Human Life Science R&D Center, Nippon Suisan Kaisha, Ltd. , Tokyo , Japan
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Singh S, Raju K, Jatekar D, Dinesh N, Paul MS, Sobhia ME. Leishmania donovani eukaryotic initiation factor 5A: molecular characterization, localization and homology modelling studies. Microb Pathog 2014; 73:37-46. [PMID: 24909104 DOI: 10.1016/j.micpath.2014.05.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 05/06/2014] [Accepted: 05/20/2014] [Indexed: 11/16/2022]
Abstract
Eukaryotic translation initiation factor 5A (eIF5A) is a small acidic protein highly conserved from archaea to mammals. eIF5A is the only protein which undergoes a unique lysine residue modification to hypusine. Hypusinylation is important for the function of eIF5A which is reported to be essential for cell viability. eIF5A promotes formation of the first peptide bond at the onset of protein synthesis. However, its function in Leishmania donovani is unclear. The present study focuses on the characterization and localization of L. donovani eIF5A protein. The eIF5A gene contains an ORF of 501×bp encoding 166 amino acid residues with a predicted molecular mass and isoelectric point of 17.8 kDa and 4.83 respectively. A phylogenetic tree analysis revealed its close proximity to trypanosomes however it is distantly located from Trichomonas vaginalis and Plasmodium falciparum. The L. donovani eIF5A was expressed as a 6× His tagged protein whose identity was confirmed by western blot and MALDI. Biophysical investigation by CD revealed the predominant presence of 49% β sheet structure which correlated well with secondary structure prediction. To gain insight into the role of eIF5A in L. donovani, we investigated the subcellular distribution of eIF5A. A GFP-fusion of L. donovani eIF5A was found to be localized in cytoplasm as confirmed by subcellular fractionation. Our studies indicated that eIF5A is primarily localized to cytoplasm and is undetectable in nuclear fraction. The homology model of eIF5A of L. donovani was built and the resulting model showed acceptable Ramachandran statistics. The model is reliable and can be used to study eIF5A binding with its effector molecules.
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Affiliation(s)
- Sushma Singh
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, SAS Nagar, Mohali 160062, Punjab, India.
| | - K Raju
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, SAS Nagar, Mohali 160062, Punjab, India
| | - Deepika Jatekar
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, SAS Nagar, Mohali 160062, Punjab, India
| | - Neeradi Dinesh
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, SAS Nagar, Mohali 160062, Punjab, India
| | - M Stanley Paul
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Sector 67, SAS Nagar Mohali 160062, Punjab, India
| | - M E Sobhia
- Department of Pharmacoinformatics, National Institute of Pharmaceutical Education and Research, Sector 67, SAS Nagar Mohali 160062, Punjab, India
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Ong ST, Freeley M, Skubis-Zegadło J, Fazil MHUT, Kelleher D, Fresser F, Baier G, Verma NK, Long A. Phosphorylation of Rab5a protein by protein kinase Cϵ is crucial for T-cell migration. J Biol Chem 2014; 289:19420-34. [PMID: 24872409 DOI: 10.1074/jbc.m113.545863] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Rab GTPases control membrane traffic and receptor-mediated endocytosis. Within this context, Rab5a plays an important role in the spatial regulation of intracellular transport and signal transduction processes. Here, we report a previously uncharacterized role for Rab5a in the regulation of T-cell motility. We show that Rab5a physically associates with protein kinase Cϵ (PKCϵ) in migrating T-cells. After stimulation of T-cells through the integrin LFA-1 or the chemokine receptor CXCR4, Rab5a is phosphorylated on an N-terminal Thr-7 site by PKCϵ. Both Rab5a and PKCϵ dynamically interact at the centrosomal region of migrating cells, and PKCϵ-mediated phosphorylation on Thr-7 regulates Rab5a trafficking to the cell leading edge. Furthermore, we demonstrate that Rab5a Thr-7 phosphorylation is functionally necessary for Rac1 activation, actin rearrangement, and T-cell motility. We present a novel mechanism by which a PKCϵ-Rab5a-Rac1 axis regulates cytoskeleton remodeling and T-cell migration, both of which are central for the adaptive immune response.
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Affiliation(s)
- Seow Theng Ong
- From the From the Department of Clinical Medicine, Institute of Molecular Medicine, Trinity College Dublin, Dublin 8, Ireland
| | - Michael Freeley
- From the From the Department of Clinical Medicine, Institute of Molecular Medicine, Trinity College Dublin, Dublin 8, Ireland
| | - Joanna Skubis-Zegadło
- From the From the Department of Clinical Medicine, Institute of Molecular Medicine, Trinity College Dublin, Dublin 8, Ireland, Department of Applied Pharmacy and Bioengineering, Medical University of Warsaw, 02-091 Warsaw, Poland
| | | | - Dermot Kelleher
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 637553, Faculty of Medicine, Imperial College London, Exhibition Road, London SW7 2AZ, United Kingdom, and
| | - Friedrich Fresser
- the Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, A-6020 Innsbruck, Austria
| | - Gottfried Baier
- the Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, A-6020 Innsbruck, Austria
| | - Navin Kumar Verma
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 637553,
| | - Aideen Long
- From the From the Department of Clinical Medicine, Institute of Molecular Medicine, Trinity College Dublin, Dublin 8, Ireland,
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Arora A, Dey CS. SIRT2 negatively regulates insulin resistance in C2C12 skeletal muscle cells. Biochim Biophys Acta Mol Basis Dis 2014; 1842:1372-8. [PMID: 24793418 DOI: 10.1016/j.bbadis.2014.04.027] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 04/25/2014] [Accepted: 04/28/2014] [Indexed: 11/19/2022]
Abstract
SIRT2 is primarily a cytoplasmic protein deacetylase and is abundantly expressed in metabolically active tissues like adipocytes and brain. However, its role, if any, in regulating insulin signaling in skeletal muscle cells, is not known. We have examined the role of SIRT2 in insulin-mediated glucose disposal in normal and insulin resistant C2C12 skeletal muscle cells in vitro. SIRT2 was over expressed in insulin resistant skeletal muscle cells. Pharmacological inhibition of SIRT2 increased insulin-stimulated glucose uptake and improved phosphorylation of Akt and GSK3β in insulin resistant cells. Knockdown of endogenous SIRT2 and over expression of catalytically-inactive SIRT2 mutant under insulin-resistant condition showed similar amelioration of insulin sensitivity. Our results suggest that down-regulation of SIRT2 improved insulin sensitivity in skeletal muscle cells under insulin-resistant condition. Previously it has been reported that down-regulation of SIRT1 and SIRT3 in C2C12 cells results in impairment of insulin signaling and induces insulin resistance. However, we have observed an altogether different role of SIRT2 in skeletal muscle. This implicates a differential regulation of insulin resistance by sirtuins which otherwise share a conserved catalytic domain. The study significantly directs towards future approaches in targeting inhibition of SIRT2 for therapeutic treatment of insulin resistance which is the major risk factor in Type 2 diabetes.
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Affiliation(s)
- Amita Arora
- Kusuma School of Biological Sciences, Indian Institute of Technology-Delhi, Hauz Khas, New Delhi 110016, India
| | - Chinmoy Sankar Dey
- Kusuma School of Biological Sciences, Indian Institute of Technology-Delhi, Hauz Khas, New Delhi 110016, India.
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Zhao P, Yang X. Vanadium compounds modulate PPARγ activity primarily by increasing PPARγ protein levels in mouse insulinoma NIT-1 cells. Metallomics 2014; 5:836-43. [PMID: 23456093 DOI: 10.1039/c3mt20249f] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Vanadium compounds are promising agents in the therapeutic treatment of diabetes; however, their mechanism of action has not been clearly elucidated. The current study investigated the effects of vanadium compounds, vanadyl acetylacetonate [V(IV)O(acac)2] and sodium metavanadate (NaV(V)O3), on peroxisome proliferator-activated receptors (PPARs), especially PPARγ, which are important targets of anti-diabetic drugs. Our experimental results revealed that treatment of NIT-1 β-pancreas cells with vanadium compounds resulted in PPARγ activation and elevation of PPARγ protein levels. Vanadium compounds did not increase PPARγ transcription but ameliorated PPARγ degradation induced by inflammatory stimulators TNF-α/IL-6. Vanadium compounds induced binding of PPARγ to heat shock protein (Hsp60). This PPARγ-Hsp60 interaction might cause inhibition of PPARγ degradation, thus elevating the PPARγ level. In addition, modulation of PPARγ phosphorylation was also observed upon vanadium treatment. The present work demonstrated for the first time that vanadium compounds are novel PPARγ modulators. The results may provide new insights for the mechanism of anti-diabetic action of vanadium compounds.
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Affiliation(s)
- Pan Zhao
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Chemical Biology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, P. R. China
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30
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Che BN, Oksbjerg N, Hellgren LI, Nielsen JH, Young JF. Phytanic acid stimulates glucose uptake in a model of skeletal muscles, the primary porcine myotubes. Lipids Health Dis 2013; 12:14. [PMID: 23398851 PMCID: PMC3606424 DOI: 10.1186/1476-511x-12-14] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 01/31/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Phytanic acid (PA) is a chlorophyll metabolite with potentials in regulating glucose metabolism, as it is a natural ligand of the peroxisome proliferator-activated receptor (PPAR) that is known to regulate hepatic glucose homeostasis. This study aimed to establish primary porcine myotubes as a model for measuring glucose uptake and glycogen synthesis, and to examine the impact of physiological amounts of PA on glucose uptake and glycogen synthesis either alone or in combination with insulin. METHODS Porcine satellite cells were cultured into differentiated myotubes and tritiated 2-deoxyglucose (2-DOG) was used to measure glucose uptake, in relation to PA and 2-DOG exposure times and also in relation to PA and insulin concentrations. The MIXED procedure model of SAS was used for statistical analysis of data. RESULTS PA increased glucose uptake by approximately 35%, and the presence of insulin further increased the uptake, but this further increase in uptake was non- additive and less pronounced at high insulin concentrations. There was no effect of PA alone on glycogen synthesis, while the insulin stimulation of glycogen was increased by 20% in the presence of PA. PA neither stimulated glucose uptake nor glycogen synthesis in insulin-resistant myotubes generated by excess glucose exposure. CONCLUSIONS Primary porcine myotubes were established as a model of skeletal muscles for measuring glucose uptake and glycogen synthesis, and we showed that PA can play a role in stimulating glucose uptake at no or inadequate insulin concentrations.
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Affiliation(s)
- Brita N Che
- Department of Food Science, Aarhus University, Blichers Allé 20, Tjele, 8830, Denmark
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31
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Hu S, Yao J, Howe AA, Menke BM, Sivitz WI, Spector AA, Norris AW. Peroxisome proliferator-activated receptor γ decouples fatty acid uptake from lipid inhibition of insulin signaling in skeletal muscle. Mol Endocrinol 2012; 26:977-88. [PMID: 22474127 DOI: 10.1210/me.2011-1253] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Peroxisome proliferator-activated receptor γ (PPARγ) is expressed at low levels in skeletal muscle, where it protects against adiposity and insulin resistance via unclear mechanisms. To test the hypothesis that PPARγ directly modulates skeletal muscle metabolism, we created two models that isolate direct PPARγ actions on skeletal myocytes. PPARγ was overexpressed in murine myotubes by adenotransfection and in mouse skeletal muscle by plasmid electroporation. In cultured myotubes, PPARγ action increased fatty acid uptake and incorporation into myocellular lipids, dependent upon a 154 ± 20-fold up-regulation of CD36 expression. PPARγ overexpression more than doubled insulin-stimulated thymoma viral proto-oncogene (AKT) phosphorylation during low lipid availability. Furthermore, in myotubes exposed to palmitate levels that inhibit insulin signaling, PPARγ overexpression increased insulin-stimulated AKT phosphorylation and glycogen synthesis over 3-fold despite simultaneously increasing myocellular palmitate uptake. The insulin signaling enhancement was associated with an increase in activating phosphorylation of phosphoinositide-dependent protein kinase 1 and a normalized expression of palmitate-induced genes that antagonize AKT phosphorylation. In vivo, PPARγ overexpression more than doubled insulin-dependent AKT phosphorylation in lipid-treated mice but did not augment insulin-stimulated glucose uptake. We conclude that direct PPARγ action promotes myocellular storage of energy by increasing fatty acid uptake and esterification while simultaneously enhancing insulin signaling and glycogen formation. However, direct PPARγ action in skeletal muscle is not sufficient to account for the hypoglycemic actions of PPARγ agonists during lipotoxicity.
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Affiliation(s)
- Shanming Hu
- Department of Pediatrics, University of Iowa, Iowa City, IA 52242, USA
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32
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Wang L, Guo F, Wei S, Zhao R. Divergent effects of GLP-1 analogs exendin-4 and exendin-9 on the expression of myosin heavy chain isoforms in C2C12 myotubes. Peptides 2011; 32:1313-9. [PMID: 21453734 DOI: 10.1016/j.peptides.2011.03.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 03/21/2011] [Accepted: 03/21/2011] [Indexed: 10/18/2022]
Abstract
Exendin 1-39 amide (Ex-4) and its truncated form exendin 9-39 amide (Ex-9) are peptides of non-mammalian nature, which act as an agonist and antagonist, respectively, of the glucagon-like peptide-1 (GLP-1) receptor in mammals. GLP-1 is an intestinal peptide that plays an important role in the regulation of glucose metabolism and glucose uptake in skeletal muscle; however, the effects of its two analogs (Ex-4 and Ex-9) on myofiber properties are still unclear. Here, we report the effects of Ex-4 and Ex-9 alone or in combination on the myosin heavy chain (MyHC) type composition and the glucose uptake capacity in differentiated C2C12 myotubes. Neither Ex-4 nor Ex-9 altered basal glucose uptake, whereas Ex-9 significantly increased insulin-stimulated glucose uptake, suggesting enhanced insulin sensitivity. The mRNA expression of MyHC I and 2A as well as the percentage of MyHC I protein was remarkably increased in Ex-9-treated myotubes. In contrast, Ex-4, alone or in combination with Ex-9, caused a significant reduction in MyHC 2A mRNA expression and the percentage of MyHC I protein. Consistent with the MyHC type switching peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α expression in myotubes was remarkably increased by Ex-9 yet was significantly inhibited by Ex-4. In addition, intracellular concentrations of free Ca(2+) were increased in all treatment groups, but only Ex-9-treated myotubes showed higher calcineurin A protein content. Taken together, our data suggest that Ex-9 promotes oxidative differentiation in myotubes to improve cell insulin sensitivity, probably through calcineurin and PGC-1α mediated pathways.
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Affiliation(s)
- Lina Wang
- Key Laboratory of Animal Physiology & Biochemistry, Nanjing Agricultural University, Nanjing 210095, PR China
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Verma NK, Dempsey E, Freeley M, Botting CH, Long A, Kelleher D, Volkov Y. Analysis of dynamic tyrosine phosphoproteome in LFA-1 triggered migrating T-cells. J Cell Physiol 2011; 226:1489-98. [PMID: 20945386 DOI: 10.1002/jcp.22478] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The ordered, directional migration of T-lymphocytes is a key process during immune surveillance and response. This requires cell adhesion to the high endothelial venules or to the extracellular matrix by a series of surface receptor/ligand interactions involving adhesion molecules of the integrin family including lymphocyte function associated molecule-1 (LFA-1) and intercellular adhesion molecules (ICAMs). Reversible protein phosphorylation is emerging as a key player in the regulation of biological functions with tyrosine phosphorylation playing a crucial role in signal transduction. Thus, the study of this type of post-translational modification at the proteomic level has great biological significance. In this work, phospho-enriched cell lysates from LFA-1-triggered migrating human T-cells were subjected to immunoaffinity purification of tyrosine phosphorylated proteins, mass spectrometric, and bioinformatic analysis. In addition to the identification of several well-documented proteins, the analysis suggested involvement of a number of new and novel proteins in LFA-1 induced T-cell migration. This dataset expands the list of the signaling components of the LFA-1 induced phosphotyrosine protein complexes in migrating T-cells that will be extremely useful in the study of their specific roles within LFA-1 associated signaling pathways. Identification of proteins previously not reported in the context of LFA-1 stimulated signal transduction might provide new insights into understanding the LFA-1 signaling networks and aid in the search for new potential therapeutic targets.
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Affiliation(s)
- Navin K Verma
- Department of Clinical Medicine, Institute of Molecular Medicine, Trinity College Dublin, Ireland.
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Irbesartan enhances GLUT4 translocation and glucose transport in skeletal muscle cells. Eur J Pharmacol 2010; 649:23-8. [DOI: 10.1016/j.ejphar.2010.08.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 07/09/2010] [Accepted: 08/21/2010] [Indexed: 01/16/2023]
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Li W, He X, Shi W, Jia H, Zhong B. Pan-PPAR Agonists Based on the Resveratrol Scaffold: Biological Evaluation and Docking Studies. ChemMedChem 2010; 5:1977-82. [DOI: 10.1002/cmdc.201000360] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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36
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Gene Expression Changes Induced by PPAR Gamma Agonists in Animal and Human Liver. PPAR Res 2010; 2010:325183. [PMID: 20981297 PMCID: PMC2963138 DOI: 10.1155/2010/325183] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2010] [Accepted: 07/15/2010] [Indexed: 01/15/2023] Open
Abstract
Thiazolidinediones are a class of Peroxisome Proliferator Activated Receptor γ (PPARγ) agonists that reduce insulin resistance in type 2 diabetic patients. Although no detectable hepatic toxicity has been evidenced in animal studies during preclinical trials, these molecules have nevertheless induced hepatic adverse effects in some treated patients. The mechanism(s) of hepatotoxicity remains equivocal. Several studies have been conducted using PCR analysis and microarray technology to identify possible target genes and here we review the data obtained from various in vivo and in vitro experimental models. Although PPARγ is expressed at a much lower level in liver than in adipose tissue, PPARγ agonists exert various PPARγ-dependent effects in liver in addition to PPARγ-independent effects. Differences in effects are dependent on the choice of agonist and experimental conditions in rodent animal studies and in rodent and human liver cell cultures. These effects are much more pronounced in obese and diabetic liver. Moreover, our own recent studies have shown major interindividual variability in the response of primary human hepatocyte populations to troglitazone treatment, supporting the occurrence of hepatotoxicity in only some individuals.
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Wu HS, Zhu DF, Zhou CX, Feng CR, Lou YJ, Yang B, He QJ. Insulin sensitizing activity of ethyl acetate fraction of Acorus calamus L. in vitro and in vivo. JOURNAL OF ETHNOPHARMACOLOGY 2009; 123:288-292. [PMID: 19429374 DOI: 10.1016/j.jep.2009.03.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 02/24/2009] [Accepted: 03/07/2009] [Indexed: 05/27/2023]
Abstract
UNLABELLED Acorus calamus L. (AC), family Araceae, have been used in the Indian and Chinese systems of medicine for hundreds of years. The radix of AC is widely used in the therapy of diabetes in traditional folk medicine of America and Indonesia. AIM OF THE STUDY To investigate the insulin sensitizing activity and antidiabetic effects of the ethyl acetate fraction of AC (ACE). MATERIALS AND METHODS Glucose consumption mediated by insulin was detected in L6 rat skeletal muscle cells. Diabetes and its complications related indexes were monitored after orally administrating to genetically obese diabetic C57BL/Ks db/db mice daily for 3 weeks. RESULTS ACE (12.5 and 25 microg/ml) increased glucose consumption mediated by insulin in L6 cells (p<0.05 and p<0.01). In db/db mice, ACE (100 mg/kg) significantly reduced serum glucose, triglyceride, reinforce the decrease of total cholesterol caused by rosiglitazone (at least p<0.05), and markedly reduced free fatty acid (FFA) levels and increased adiponectin levels (p<0.01 and p<0.05) as rosiglitazone did (p<0.05 and p<0.001). Serum insulin was decreased but not significantly. In addition, ACE decreased the intake of food and water, and did not increase body weight gain whereas rosiglitazone did. CONCLUSIONS Owing to the ability of insulin sensitizing, ACE has the potential to be useful for the treatment of diabetes and cardiovascular complications without body weight gain.
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Affiliation(s)
- Hao-Shu Wu
- Institute of Pharmacology & Toxicology and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, 388 Yu-hang-tang Road, Hangzhou, China.
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Zhu MJ, Han B, Tong J, Ma C, Kimzey JM, Underwood KR, Xiao Y, Hess BW, Ford SP, Nathanielsz PW, Du M. AMP-activated protein kinase signalling pathways are down regulated and skeletal muscle development impaired in fetuses of obese, over-nourished sheep. J Physiol 2008; 586:2651-64. [PMID: 18372306 DOI: 10.1113/jphysiol.2007.149633] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Maternal obesity and over-nutrition give rise to both obstetric problems and neonatal morbidity. The objective of this study was to evaluate effects of maternal obesity and over-nutrition on signalling of the AMP-activated protein kinase (AMPK) pathway in fetal skeletal muscle in an obese pregnant sheep model. Non-pregnant ewes were assigned to a control group (Con, fed 100% of NRC nutrient recommendations, n = 7) or obesogenic group (OB, fed 150% of National Research Council (NRC) recommendations, n = 7) diet from 60 days before to 75 days after conception (term 150 days) when fetal semitendinosus skeletal muscle (St) was sampled. OB mothers developed severe obesity accompanied by higher maternal and fetal plasma glucose and insulin levels. In fetal St, activity of phosphoinositide-3 kinase (PI3K) associated with insulin receptor substrate-1 (IRS-1) was attenuated (P < 0.05), in agreement with the increased phophorylation of IRS-1 at serine 1011. Phosphorylation of AMP-activated protein kinase (AMPK) at Thr 172, acetyl-CoA carboxylase at Ser 79, tuberous sclerosis 2 at Thr 1462 and eukaryotic translation initiation factor 4E-binding protein 1 at Thr 37/46 were reduced in OB compared to Con fetal St. No difference in energy status (AMP/ATP ratio) was observed. The expression of protein phosphatase 2C was increased in OB compared to Con fetal St. Plasma tumour necrosis factor alpha (TNFalpha) was increased in OB fetuses indicating an increased inflammatory state. Expression of peroxisome proliferator-activated receptor gamma (PPARgamma) was higher in OB St, indicating enhanced adipogenesis. The glutathione: glutathione disulphide ratio was also lower, showing increased oxidative stress in OB fetal St. In summary, we have demonstrated decreased signalling of the AMPK system in skeletal muscle of fetuses of OB mothers, which may play a role in altered muscle development and development of insulin resistance in the offspring.
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Affiliation(s)
- Mei J Zhu
- Department of Animal Science and Interdepartmental Molecular and Cellular Life Sciences Program, University of Wyoming, Laramie, WY 82071, USA
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Tong J, Zhu MJ, Underwood KR, Hess BW, Ford SP, Du M. AMP-activated protein kinase and adipogenesis in sheep fetal skeletal muscle and 3T3-L1 cells. J Anim Sci 2008; 86:1296-305. [PMID: 18344293 DOI: 10.2527/jas.2007-0794] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Marbling, or i.m. fat, is an important factor determining beef quality. Both adipogenesis and hypertrophy of existing adipocytes contribute to enhanced marbling. We hypothesized that the fetal stage is important for the formation of i.m. adipocytes and that AMP-activated protein kinase (AMPK) has a key role in adipogenesis during this stage. The objective of this study was to assess the role of AMPK in adipogenesis in fetal sheep muscle and 3T3-L1 cells. Nonpregnant ewes were randomly assigned to a control (Con, 100% of NRC recommendations, n = 7) or overfed (OF, 150% of NRC, n = 7) diet from 60 d before to 75 d after conception, when the ewes were killed. The fetal LM was collected at necropsy for biochemical analyses. The activity of AMPK was less in the fetal muscle of OF sheep. The expression of peroxisome proliferator-activated receptor (PPAR)gamma, a marker of adipogenesis, was greater in OF fetal muscle compared with Con fetal muscle. To further show the role of AMPK in adipogenesis, we used 3T3-L1 cells. The 3T3-L1 cells were incubated in a standard adipogenic medium for 24 h and 10 d. Activation of AMPK by 5-aminoimidazole-4-car-boxamide-1-beta-d-ribonucleoside dramatically inhibited the expression of PPARgamma and reduced the presence of adipocytes after 10 d of differentiation. Inhibition of AMPK by compound C enhanced the expression of PPARgamma. In conclusion, these data show that AMPK activity is inversely related to adipogenesis in fetal sheep muscle and 3T3-L1 cells.
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Affiliation(s)
- J Tong
- Department of Animal Science and Interdepartmental Molecular and Cellular Life Sciences Program, University of Wyoming, Laramie 82071, USA
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A new microtubule-targeting compound PBOX-15 inhibits T-cell migration via post-translational modifications of tubulin. J Mol Med (Berl) 2008; 86:457-69. [DOI: 10.1007/s00109-008-0312-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Revised: 12/07/2007] [Accepted: 12/27/2007] [Indexed: 10/22/2022]
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Hevener AL, Olefsky JM, Reichart D, Nguyen MA, Bandyopadyhay G, Leung HY, Watt MJ, Benner C, Febbraio MA, Nguyen AK, Folian B, Subramaniam S, Gonzalez FJ, Glass CK, Ricote M. Macrophage PPAR gamma is required for normal skeletal muscle and hepatic insulin sensitivity and full antidiabetic effects of thiazolidinediones. J Clin Invest 2007; 117:1658-69. [PMID: 17525798 PMCID: PMC1868788 DOI: 10.1172/jci31561] [Citation(s) in RCA: 389] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Accepted: 03/20/2007] [Indexed: 02/06/2023] Open
Abstract
PPAR gamma is required for fat cell development and is the molecular target of antidiabetic thiazolidinediones (TZDs), which exert insulin-sensitizing effects in adipose tissue, skeletal muscle, and liver. Unexpectedly, we found that inactivation of PPAR gamma in macrophages results in the development of significant glucose intolerance plus skeletal muscle and hepatic insulin resistance in lean mice fed a normal diet. This phenotype was associated with increased expression of inflammatory markers and impaired insulin signaling in adipose tissue, muscle, and liver. PPAR gamma-deficient macrophages secreted elevated levels of factors that impair insulin responsiveness in muscle cells in a manner that was enhanced by exposure to FFAs. Consistent with this, the relative degree of insulin resistance became more severe in mice lacking macrophage PPAR gamma following high-fat feeding, and these mice were only partially responsive to TZD treatment. These findings reveal an essential role of PPAR gamma in macrophages for the maintenance of whole-body insulin action and in mediating the antidiabetic actions of TZDs.
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Affiliation(s)
- Andrea L. Hevener
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Jerrold M. Olefsky
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Donna Reichart
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - M.T. Audrey Nguyen
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Gautam Bandyopadyhay
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Ho-Yin Leung
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Matthew J. Watt
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Chris Benner
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Mark A. Febbraio
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Anh-Khoi Nguyen
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Brian Folian
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Shankar Subramaniam
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Frank J. Gonzalez
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Christopher K. Glass
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
| | - Mercedes Ricote
- Department of Medicine, Division of Endocrinology and Metabolism, and
Department of Cellular and Molecular Medicine, UCSD, La Jolla, California, USA.
St. Vincent’s Institute of Medical Research, Department of Medicine, The University of Melbourne, Fitzroy, Victoria, Australia.
Department of Bioengineering, UCSD, La Jolla, California, USA.
Baker Heart Institute, Cellular and Molecular Medicine Laboratory, St. Kilda, Victoria, Australia.
Laboratory of Metabolism, National Cancer Institute, Bethesda, Maryland, USA.
Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain
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Verma NK, Singh G, Dey CS. Miltefosine induces apoptosis in arsenite-resistant Leishmania donovani promastigotes through mitochondrial dysfunction. Exp Parasitol 2007; 116:1-13. [PMID: 17161839 DOI: 10.1016/j.exppara.2006.10.007] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 10/05/2006] [Accepted: 10/13/2006] [Indexed: 11/30/2022]
Abstract
The control of leishmaniasis in absence of vaccine solely depends on the choice of chemotherapy. The major hurdle in successful leishmanial chemotherapy is emergence of drug resistance. Miltefosine, the first orally administrable anti-leishmanial drug, has shown the potential against drug-resistant strains of Leishmania. However, there are discrepancies regarding the involvement of P-glycoprotein (Pgp) and sensitivity of miltefosine in multiple drug-resistant (MDR) cell lines that overexpress Pgp in Leishmania. To address this, the effect of miltefosine in arsenite-resistant Leishmania donovani (Ld-As20) promastigotes displaying an MDR phenotype and overexpressing Pgp-like protein was investigated in the current study. Results indicate that Ld-As20 is sensitive to miltefosine. Miltefosine induces process of programmed cell death in Ld-As20 in a time-dependent manner as determined by cell shrinkage, externalization of phosphatidylserine and DNA fragmentation. Miltefosine treatment leads to loss of mitochondrial membrane potential and the release of cytochrome C with consequent activation of cellular proteases. Activation of cellular proteases resulted in activation of DNase that damaged kinetoplast DNA and induced dyskinetoplasty. These data indicate that miltefosine causes apoptosis-like death in arsenite-resistant L. donovani.
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Affiliation(s)
- Navin K Verma
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER)(1), Punjab 160 062, India
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43
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Bisht B, Goel HL, Dey CS. Focal adhesion kinase regulates insulin resistance in skeletal muscle. Diabetologia 2007; 50:1058-69. [PMID: 17333113 DOI: 10.1007/s00125-007-0591-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2006] [Accepted: 10/15/2006] [Indexed: 10/23/2022]
Abstract
AIMS/HYPOTHESIS On the basis of our previous studies, we investigated the possible role of focal adhesion kinase (FAK) in the development of insulin resistance in skeletal muscle, a major organ responsible for insulin-stimulated glucose uptake. MATERIALS AND METHODS Insulin-resistant C2C12 skeletal muscle cells were transfected with FAK wild-type or FAK mutant plasmids, knocked down using small interfering RNA (siRNA), and their effects on the levels and activities of insulin-signalling molecules and on glucose uptake were determined. RESULTS A significant decrease in tyrosine phosphorylation of FAK in insulin-resistant C2C12 cells was observed. A similar decrease was observed in skeletal muscle obtained from insulin-resistant Sprague-Dawley rats fed a high-fat diet. Increased levels of FAK in insulin-resistant C2C12 skeletal muscle cells increased insulin sensitivity and glucose uptake. These effects were reversed by an increase in the level of kinase activity mutant FAK or suppression of endogenous FAK by siRNA. FAK was also found to interact downstream with insulin receptor substrate-1, phosphatidylinositol 3-kinase and protein kinase C and glycogen synthase kinase 3beta, leading to translocation of glucose transporter 4 and resulting in the regulation of glucose uptake. CONCLUSIONS/INTERPRETATION The present study provides strong evidence that the modulation of FAK level regulates the insulin sensitivity of skeletal muscle cells. The results demonstrate a direct role of FAK in insulin-resistant skeletal muscle cells for the first time.
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Affiliation(s)
- B Bisht
- Signal Transduction Research Laboratory, Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), Sector 67, S.A.S. Nagar, Chandigarh 160062, India
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Ma MM, Chen JL, Wang GG, Wang H, Lu Y, Li JF, Yi J, Yuan YJ, Zhang QW, Mi J, Wang LS, Duan HF, Wu CT. Sphingosine kinase 1 participates in insulin signalling and regulates glucose metabolism and homeostasis in KK/Ay diabetic mice. Diabetologia 2007; 50:891-900. [PMID: 17265031 DOI: 10.1007/s00125-006-0589-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2006] [Accepted: 12/15/2006] [Indexed: 12/27/2022]
Abstract
AIMS/HYPOTHESIS The aim of this study was to determine the potential role of sphingosine kinase 1 (SPHK1), a key sphingolipid metabolic enzyme, in glucose metabolism and homeostasis. METHODS SMMC-7721 hepatoma cells and C2C12 myotube cells were used to explore the role of SPHK1 in glucose uptake in vitro. KK/Ay type 2 diabetic mice, which were transfected with adenovirus harbouring the human SPHK1 gene by i.v. injection, were used to investigate the glucose-lowering effects of SPHK1 in vivo. RESULTS The basal glucose uptake and the insulin-stimulated glucose uptake in both 7721 cells and C2C12 cells were markedly enhanced when SPHK1 was overexpressed by adenovirus-mediated gene transfer, whereas they were substantially reduced when the expression of SPHK1 was inhibited or the activity of SPHK1 was blocked. Insulin could activate SPHK1 of both cell lines in a dose-dependent manner. SPHK1 gene delivery significantly reduced the blood glucose level of KK/Ay diabetic mice, but had no effect on that of normal animals. It also attenuated elevated levels of plasma insulin, NEFA, triacylglycerol, cholesterol and LDL, significantly ameliorated hyperglycaemia-induced injury of liver, heart and kidney, and enhanced phosphorylation of insulin-signalling kinases such as Akt and glycogen synthase kinase 3beta in livers of the diabetic animals. CONCLUSIONS/INTERPRETATION SPHK1 is involved in insulin signalling and plays an important role in the regulation of glucose and fat metabolism; adenovirus-mediated SPHK1 gene transfer might provide a novel strategy in the treatment of type 2 diabetes mellitus.
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Affiliation(s)
- M M Ma
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, People's Republic of China
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Kim KY, Cho HS, Jung WH, Kim SS, Cheon HG. Phosphatase and Tensin Homolog Deleted on Chromosome 10 Suppression Is an Important Process in Peroxisome Proliferator-Activated Receptor-γ Signaling in Adipocytes and Myotubes. Mol Pharmacol 2007; 71:1554-62. [PMID: 17337625 DOI: 10.1124/mol.106.031948] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Peroxisome proliferator-activated receptor-gamma (PPARgamma) activation enhances insulin sensitivity in type 2 diabetes mellitus. However, downstream mediators of PPARgamma activation in adipocytes and myotubes, the most important cell types involved in glucose homeostasis, remained unclear. Here we show by using two synthetic PPARgamma agonists (rosiglitazone and KR-62776, a novel PPARgamma agonist) that phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a key downstream mediator of PPARgamma signaling. The PPARgamma agonists down-regulated PTEN expression, resulting in glucose uptake increase in differentiated 3T3-L1 adipocytes and C2C12 skeletal muscle cells. In both cells, PTEN knockdown increased glucose uptake, whereas overexpression abolished the agonist-induced effects. The effects of PPARgamma agonists on PTEN expression and glucose uptake disappeared by pretreatment with a PPARgamma antagonist or by knockdown of PPARgamma expression. In vivo treatment of the agonists to C57BL/6J-ob/ob mice resulted in the reduction of PTEN level in both adipose and skeletal muscle tissues and decreased plasma glucose levels. Thus, these results suggest that PTEN suppression is a key mechanism of the PPARgamma-mediated glucose uptake stimulation in insulin-sensitive cells such as adipocytes and skeletal muscle cells, thereby restoring glucose homeostasis in type 2 diabetes.
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Affiliation(s)
- Ki Young Kim
- Bio-Organic Science Division, Korea Research Institute of Chemical Technology, Daejeon, Korea
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Sharma S, Sowjanya A, Kumari M, Suryaprakash R, Cynthia G, Suresh J, Chakrabarti R. Biochemical mechanism of insulin sensitization, lipid modulation and anti-atherogenic potential of PPAR alpha/gamma dual agonist: Ragaglitazar. Life Sci 2006; 80:235-44. [PMID: 17014868 DOI: 10.1016/j.lfs.2006.09.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Revised: 08/25/2006] [Accepted: 09/06/2006] [Indexed: 02/02/2023]
Abstract
The current goal in the treatment of diabetes is not only to enhance the glycemic control but also to improve the associated cardiovascular risk factors. Among many of the strategies available, a co-ligand of PPARalpha and gamma in a single molecule which combines the insulin sensitizing potential of PPARgamma and the beneficial lipid modulating properties of PPARalpha agonism, has gained attention in the recent past. Here we report the biochemical mechanism by which a dual PPAR alpha/gamma agonist Ragaglitazar (Raga) achieves this goal. The PPARalpha component of Raga appears to contribute to a significant increase in beta oxidation, ApoA1 secretion and inhibition of TG biosynthesis in HepG2 cells. These effects of Raga at 60 microM were similar to that shown by Fenofibrate (Feno) at 250 microM. The PPARgamma component of Raga showed significant G3PDH activity and TG accumulation with a corresponding increase in aP2 expression in 3T3L1 cells. Significantly reduced levels of IL-6 and TNFalpha were observed in the culture supernatants of Raga treated 3T3L1 cells. Raga resulted in significant insulin dependent glucose uptake in 3T3L1 with a corresponding increase in GLUT4 expression. Further, Raga showed a significant cholesterol efflux with a corresponding increase in ABCA1 protein expression in THP-1 macrophages. In conclusion, Raga activates both PPARalpha and gamma regulated pathway in adipocytes as well as in hepatocytes which together contributes for its insulin sensitizing and lipid lowering activity. In addition the dual activation of PPAR alpha/gamma also shows an athero-protective potential by inducing reverse cholesterol efflux and inhibiting the pro-inflammatory cytokines.
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Affiliation(s)
- Sudhir Sharma
- Metabolic Disorder Group, Discovery Biology, Dr. Reddy's Laboratories Limited-Discovery Research, Bollaram Road, Miyapur, Hyderabad-500 049, India
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Smith AG, Muscat GEO. Orphan nuclear receptors: therapeutic opportunities in skeletal muscle. Am J Physiol Cell Physiol 2006; 291:C203-17. [PMID: 16825600 DOI: 10.1152/ajpcell.00476.2005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Nuclear hormone receptors (NRs) are ligand-dependent transcription factors that bind DNA and translate physiological signals into gene regulation. The therapeutic utility of NRs is underscored by the diversity of drugs created to manage dysfunctional hormone signaling in the context of reproductive biology, inflammation, dermatology, cancer, and metabolic disease. For example, drugs that target nuclear receptors generate over $10 billion in annual sales. Almost two decades ago, gene products were identified that belonged to the NR superfamily on the basis of DNA and protein sequence identity. However, the endogenous and synthetic small molecules that modulate their action were not known, and they were denoted orphan NRs. Many of the remaining orphan NRs are highly enriched in energy-demanding major mass tissues, including skeletal muscle, brown and white adipose, brain, liver, and kidney. This review focuses on recently adopted and orphan NR function in skeletal muscle, a tissue that accounts for approximately 35% of the total body mass and energy expenditure, and is a major site of fatty acid and glucose utilization. Moreover, this lean tissue is involved in cholesterol efflux and secretes that control energy expenditure and adiposity. Consequently, muscle has a significant role in insulin sensitivity, the blood lipid profile, and energy balance. Accordingly, skeletal muscle plays a considerable role in the progression of dyslipidemia, diabetes, and obesity. These are risk factors for cardiovascular disease, which is the the foremost cause of global mortality (>16.7 million deaths in 2003). Therefore, it is not surprising that orphan NRs and skeletal muscle are emerging as therapeutic candidates in the battle against dyslipidemia, diabetes, obesity, and cardiovascular disease.
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Affiliation(s)
- Aaron G Smith
- Institute for Molecular Bioscience, Univ. of Queensland, St. Lucia 4072, Queensland, Australia.
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Singh J, Verma NK, Kansagra SM, Kate BN, Dey CS. Altered PPARgamma expression inhibits myogenic differentiation in C2C12 skeletal muscle cells. Mol Cell Biochem 2006; 294:163-71. [PMID: 16838108 DOI: 10.1007/s11010-006-9256-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2006] [Accepted: 06/01/2006] [Indexed: 10/24/2022]
Abstract
Peroxisome proliferator-activated receptor gamma (PPARgamma) is a member of the nuclear receptor superfamily known to regulate adipocyte differentiation. However, its role in skeletal muscle differentiation is not known. To investigate possible involvement of PPARgamma in skeletal muscle differentiation, we modulated its expression in C2C12 mouse skeletal muscle cells by stable transfection with sense or antisense plasmid constructs of PPARgamma cDNA. Phenotypic observations and biochemical analysis of different myogenic markers showed that altered expression of PPARgamma inhibited the formation of myotubes, as well as expression of muscle-specific myogenic proteins including myogenin, MyoD and creatine kinase activity. Together, we show that critical expression of PPARgamma is required for skeletal muscle cells differentiation.
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Affiliation(s)
- Jaskirat Singh
- Signal Transduction Research Laboratory, Department of Biotechnology, National Institute of Pharmaceutical Education and Research (NIPER), SAS Nagar, Punjab, India
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Sugden MC, Holness MJ. Skeletal muscle lipid metabolism and the adipomuscular axis. ACTA ACUST UNITED AC 2006. [DOI: 10.2217/17460875.1.2.153] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ko BS, Choi SB, Park SK, Jang JS, Kim YE, Park S. Insulin sensitizing and insulinotropic action of berberine from Cortidis rhizoma. Biol Pharm Bull 2005; 28:1431-7. [PMID: 16079488 DOI: 10.1248/bpb.28.1431] [Citation(s) in RCA: 138] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Our preliminary study demonstrated that 70% ethanol Cortidis Rhizoma extracts (CR) had a hypoglycemic action in diabetic animal models. We determined whether CR fractions acted as anti-diabetic agent, and a subsequent investigation of the action mechanism of the major compound, berberine ([C(20)H(18)NO(4)](+)), was carried out in vitro. The 20, 40 and 60% methanol fractions from the XAD-4 column contained the most insulin sensitizing activities in 3T3-L1 adipocytes. The common major peak in these fractions was berberine. Treatment with 50 microM berberine plus differentiation inducers significantly reduced triglyceride accumulation by decreased differentiation of 3T3-L1 fibroblasts to adipocytes and triglyceride synthesis. Significant insulin sensitizing activity was observed in 3T3-L1 adipocytes which were given 50 microM berberine plus 0.2 nM insulin to reach a glucose uptake level increased by 10 nM of insulin alone. This was associated with increased glucose transporter-4 translocation into the plasma membrane via enhancing insulin signaling pathways and the insulin receptor substrate-1-phosphoinositide 3 Kinase-Akt. Berberine also increased glucose-stimulated insulin secretion and proliferation in Min6 cells via an enhanced insulin/insulin-like growth factor-1 signaling cascade. Data suggested that berberine can act as an effective insulin sensitizing and insulinotropic agent. Therefore, berberine can be used as anti-diabetic agent for obese diabetic patients.
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Affiliation(s)
- Byoung-Seob Ko
- Department of Quality Inspection and Examination, Korea Institute of Oriental Medicine, Daejun 305-390, Korea
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