Nymphaea rubra ameliorates TNF-α-induced insulin resistance via suppression of c-Jun NH2-terminal kinase and nuclear factor-κB in the rat skeletal muscle cells

Appl Biochem Biotechnol. 2014 Dec;174(7):2446-57. doi: 10.1007/s12010-014-1192-8. Epub 2014 Sep 19.

Abstract

In this work, we demonstrated insulin signaling and the anti-inflammatory effects by the chloroform fraction of ethanolic extract of Nymphaea rubra flowers in TNF-α-induced insulin resistance in the rat skeletal muscle cell line (L6 myotubes) to dissect out its anti-hyperglycemic mechanism. N. rubra enhances the GLUT4-mediated glucose transport in a dose dependent manner and also increases the tyrosine phosphorylation of both IR-β and IRS-1, and the IRS-1 associated PI-3 kinase activity in TNF-α-treated L6 myotubes. Moreover, N. rubra decreases Ser(307) phosphorylation of IRS-1 by the suppression of JNK and NF-κB activation. In conclusion, N. rubra reverses the insulin resistance by the inhibition of c-Jun NH2-Terminal Kinase and Nuclear-κB.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / chemistry
  • Anti-Inflammatory Agents / pharmacology*
  • Cell Line
  • Flowers / chemistry*
  • Glucose / metabolism
  • Glucose Transporter Type 4 / metabolism
  • Hypoglycemic Agents / chemistry
  • Hypoglycemic Agents / pharmacology*
  • Insulin / metabolism
  • Insulin Resistance*
  • JNK Mitogen-Activated Protein Kinases / metabolism*
  • Muscle Fibers, Skeletal / cytology
  • Muscle Fibers, Skeletal / metabolism*
  • NF-kappa B / metabolism*
  • Nymphaea / chemistry*
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Rats
  • Tumor Necrosis Factor-alpha / metabolism*

Substances

  • Anti-Inflammatory Agents
  • Glucose Transporter Type 4
  • Hypoglycemic Agents
  • Insulin
  • NF-kappa B
  • Plant Extracts
  • Slc2a4 protein, rat
  • Tumor Necrosis Factor-alpha
  • JNK Mitogen-Activated Protein Kinases
  • Glucose