Enhanced insulin signaling in density-enhanced phosphatase-1 (DEP-1) knockout mice

Autor: Ernst Wellnhofer, Manuela Trappiel, Christa Thöne-Reineke, Kai Kappert, Arne Östman, Andreas L. Birkenfeld, Sebastian Brachs, Janine Krüger, Philipp Stawowy, Heike Meyborg, Frank-D. Böhmer, Ulrich Kintscher
Rok vydání: 2015
Předmět:
HFD
high-fat diet

lcsh:Internal medicine
medicine.medical_specialty
Protein tyrosine phosphatase
Glucose homeostasis
complex mixtures
Receptor tyrosine kinase
Dephosphorylation
Insulin resistance
Internal medicine
medicine
Density-enhanced phosphatase-1
Phosphorylation
lcsh:RC31-1245
Molecular Biology
DEP-1
density-enhanced phosphatase-1

RER
respiratory exchange ratio

ITT
insulin tolerance test

KO
knockout

biology
Insulin tolerance test
Cell Biology
respiratory system
medicine.disease
MCP-1
monocyte chemotactic protein-1

WT
wild-type

IRS2
LFD
low-fat diet

Insulin signaling
IL-6
interleukin 6

Insulin receptor
600 Technik
Medizin
angewandte Wissenschaften::630 Landwirtschaft

Endocrinology
IR
insulin receptor

biology.protein
GTT
glucose tolerance test

Original Article
RTK
receptor tyrosine kinase

PTP
protein tyrosine phosphatase
Zdroj: Molecular Metabolism, Vol 4, Iss 4, Pp 325-336 (2015)
Molecular Metabolism
ISSN: 2212-8778
DOI: 10.1016/j.molmet.2015.02.001
Popis: Objective: Insulin resistance can be triggered by enhanced dephosphorylation of the insulin receptor or downstream components in the insulin signaling cascade through protein tyrosine phosphatases (PTPs). Downregulating density-enhanced phosphatase-1 (DEP-1) resulted in an improved metabolic status in previous analyses. This phenotype was primarily caused by hepatic DEP-1 reduction. Methods: Here we further elucidated the role of DEP-1 in glucose homeostasis by employing a conventional knockout model to explore the specific contribution of DEP-1 in metabolic tissues. Ptprj−/− (DEP-1 deficient) and wild-type C57BL/6 mice were fed a low-fat or high-fat diet. Metabolic phenotyping was combined with analyses of phosphorylation patterns of insulin signaling components. Additionally, experiments with skeletal muscle cells and muscle tissue were performed to assess the role of DEP-1 for glucose uptake. Results: High-fat diet fed-Ptprj−/− mice displayed enhanced insulin sensitivity and improved glucose tolerance. Furthermore, leptin levels and blood pressure were reduced in Ptprj−/− mice. DEP-1 deficiency resulted in increased phosphorylation of components of the insulin signaling cascade in liver, skeletal muscle and adipose tissue after insulin challenge. The beneficial effect on glucose homeostasis in vivo was corroborated by increased glucose uptake in skeletal muscle cells in which DEP-1 was downregulated, and in skeletal muscle of Ptprj−/− mice. Conclusion: Together, these data establish DEP-1 as novel negative regulator of insulin signaling.
Databáze: OpenAIRE