Time-Resolved and Tissue-Specific Systems Analysis of the Pathogenesis of Insulin Resistance

PLOS ONE, Jan 2010

Background The sequence of events leading to the development of insulin resistance (IR) as well as the underlying pathophysiological mechanisms are incompletely understood. As reductionist approaches have been largely unsuccessful in providing an understanding of the pathogenesis of IR, there is a need for an integrative, time-resolved approach to elucidate the development of the disease. Methodology/Principal Findings Male ApoE3Leiden transgenic mice exhibiting a humanized lipid metabolism were fed a high-fat diet (HFD) for 0, 1, 6, 9, or 12 weeks. Development of IR was monitored in individual mice over time by performing glucose tolerance tests and measuring specific biomarkers in plasma, and hyperinsulinemic-euglycemic clamp analysis to assess IR in a tissue-specific manner. To elucidate the dynamics and tissue-specificity of metabolic and inflammatory processes key to IR development, a time-resolved systems analysis of gene expression and metabolite levels in liver, white adipose tissue (WAT), and muscle was performed. During HFD feeding, the mice became increasingly obese and showed a gradual increase in glucose intolerance. IR became first manifest in liver (week 6) and then in WAT (week 12), while skeletal muscle remained insulin-sensitive. Microarray analysis showed rapid upregulation of carbohydrate (only liver) and lipid metabolism genes (liver, WAT). Metabolomics revealed significant changes in the ratio of saturated to polyunsaturated fatty acids (liver, WAT, plasma) and in the concentrations of glucose, gluconeogenesis and Krebs cycle metabolites, and branched amino acids (liver). HFD evoked an early hepatic inflammatory response which then gradually declined to near baseline. By contrast, inflammation in WAT increased over time, reaching highest values in week 12. In skeletal muscle, carbohydrate metabolism, lipid metabolism, and inflammation was gradually suppressed with HFD. Conclusions/Significance HFD-induced IR is a time- and tissue-dependent process that starts in liver and proceeds in WAT. IR development is paralleled by tissue-specific gene expression changes, metabolic adjustments, changes in lipid composition, and inflammatory responses in liver and WAT involving p65-NFkB and SOCS3. The alterations in skeletal muscle are largely opposite to those in liver and WAT.

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Time-Resolved and Tissue-Specific Systems Analysis of the Pathogenesis of Insulin Resistance

et al. (2010) Time-Resolved and Tissue-Specific Systems Analysis of the Pathogenesis of Insulin Resistance. PLoS ONE 5(1): e8817. doi:10.1371/journal.pone.0008817 Time-Resolved and Tissue-Specific Systems Analysis of the Pathogenesis of Insulin Resistance Robert Kleemann 0 Marjan van Erk 0 Lars Verschuren 0 Anita M. van den Hoek 0 Maud Koek 0 Peter Y. Wielinga 0 Annie Jie 0 Linette Pellis 0 Ivana Bobeldijk-Pastorova 0 Thomas Kelder 0 Karin Toet 0 Suzan Wopereis 0 Nicole Cnubben 0 Chris Evelo 0 Ben van Ommen 0 Teake Kooistra 0 Jose A. L. Calbet, University of Las Palmas de Gran Canaria, Spain 0 1 Quality of Life , Vascular and Metabolic Disease, TNO, Leiden , The Netherlands , 2 Department of Vascular Surgery, Leiden University Medical Center , Leiden , The Netherlands , 3 Quality of Life , Physiological Genomics, TNO, Zeist , The Netherlands , 4 Top Institute Food and Nutrition, Wageningen, The Netherlands, 5 Department of Bioinformatics, Maastricht University , Maastricht , The Netherlands , 6 Quality of Life, Analytical Research, TNO , Zeist , The Netherlands Background: The sequence of events leading to the development of insulin resistance (IR) as well as the underlying pathophysiological mechanisms are incompletely understood. As reductionist approaches have been largely unsuccessful in providing an understanding of the pathogenesis of IR, there is a need for an integrative, time-resolved approach to elucidate the development of the disease. Methodology/Principal Findings: Male ApoE3Leiden transgenic mice exhibiting a humanized lipid metabolism were fed a high-fat diet (HFD) for 0, 1, 6, 9, or 12 weeks. Development of IR was monitored in individual mice over time by performing glucose tolerance tests and measuring specific biomarkers in plasma, and hyperinsulinemic-euglycemic clamp analysis to assess IR in a tissue-specific manner. To elucidate the dynamics and tissue-specificity of metabolic and inflammatory processes key to IR development, a time-resolved systems analysis of gene expression and metabolite levels in liver, white adipose tissue (WAT), and muscle was performed. During HFD feeding, the mice became increasingly obese and showed a gradual increase in glucose intolerance. IR became first manifest in liver (week 6) and then in WAT (week 12), while skeletal muscle remained insulin-sensitive. Microarray analysis showed rapid upregulation of carbohydrate (only liver) and lipid metabolism genes (liver, WAT). Metabolomics revealed significant changes in the ratio of saturated to polyunsaturated fatty acids (liver, WAT, plasma) and in the concentrations of glucose, gluconeogenesis and Krebs cycle metabolites, and branched amino acids (liver). HFD evoked an early hepatic inflammatory response which then gradually declined to near baseline. By contrast, inflammation in WAT increased over time, reaching highest values in week 12. In skeletal muscle, carbohydrate metabolism, lipid metabolism, and inflammation was gradually suppressed with HFD. Conclusions/Significance: HFD-induced IR is a time- and tissue-dependent process that starts in liver and proceeds in WAT. IR development is paralleled by tissue-specific gene expression changes, metabolic adjustments, changes in lipid composition, and inflammatory responses in liver and WAT involving p65-NFkB and SOCS3. The alterations in skeletal muscle are largely opposite to those in liver and WAT. - Funding: This present study was mainly sponsored by the TNO research program Personalized Health (to R.K., M.v.E., L.V., N.C., A.J., I.B-P., M.K., L.P., B.v.O., and T.K.; animal work; transcriptomics; metabolomics). The authors gratefully acknowledge additional grant support from the European Nutrigenomics Organisation (NuGO, CT-2004-505944; Proof-of-Principle Study PPS1 to R.K., M.v.E., C.E., and T.K.) and from the Top Institute Food and Nutrition (SAA, fibrinogen, E-selectin, VCAM-1, vWF measurements; Top Institute Food and Nutrition work package A1004 to K.T., P.Y.W., and R.K.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: Authors employed by TNO (R.K., M.v.E., A.J., L.V., A.M.v.d.H., M.K, P.Y.W, L.P., I.B.P., K.T., S.W., N.C., B.v.O., and T.K.) and the Top Institute Food and Nutrition (R.K., P.Y.W., and K.T.) have a potential conflict of interest as their organizations may benefit from a product or patent generated on the basis of the published data. In these cases, the authors will however not receive additional salary, additional personal income, or any form of financial support. Diabetes mellitus type 2 (DM2) is a metabolic disorder that is primarily characterized by insulin resistance (IR), relative insulin deficiency and hyperglycemia. DM2 is rapidly increasing in the developed world, and there is some evidence that this pattern will be followed in much of the rest of the world in the coming years [1]. IR is the condition in which regular amount (...truncated)


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Robert Kleemann, Marjan van Erk, Lars Verschuren, Anita M. van den Hoek, Maud Koek, Peter Y. Wielinga, Annie Jie, Linette Pellis, Ivana Bobeldijk-Pastorova, Thomas Kelder, Karin Toet, Suzan Wopereis, Nicole Cnubben, Chris Evelo, Ben van Ommen, Teake Kooistra. Time-Resolved and Tissue-Specific Systems Analysis of the Pathogenesis of Insulin Resistance, PLOS ONE, 2010, 1, DOI: 10.1371/journal.pone.0008817