Insulin mimetics in Urtica dioica: structural and computational analyses of Urtica dioica extracts

Phytother Res. 2010 Jun:24 Suppl 2:S175-82. doi: 10.1002/ptr.3062.

Abstract

Urtica Dioica (UD) is a plant shown to reduce blood glucose levels upon oral ingestion; however, neither its active component nor its mechanism of action has been identified. One active fraction of this extract, termed UD-1, was separated by molecular sieve column chromatography and purified by high performance liquid chromatography (HPLC). While UD-1 did not stimulate insulin secretion in glucose-responsive MIN6 clonal beta-cells, chronic exposure (24 h) significantly enhanced glucose uptake (approximately 1.5-fold) in L6-GLUT4myc myoblast cells. Using HPLC and MALDI-TOF, we further purified the UD-1 fraction into two fractions termed UD-1A and UD-1B. Computational and structural analyses strongly suggested that the antidiabetic component of UD-1 was due to one or more structurally related cyclical peptides that facilitate glucose uptake by forming unique glucose permeable pores. The structure and function of these glucose-conducting pores are discussed herein.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Chromatography, High Pressure Liquid
  • Glucose / metabolism
  • Hypoglycemic Agents / chemistry
  • Hypoglycemic Agents / isolation & purification*
  • Hypoglycemic Agents / pharmacology
  • Insulin / metabolism*
  • Insulin Secretion
  • Insulin-Secreting Cells / drug effects*
  • Models, Molecular
  • Molecular Structure
  • Plant Extracts / chemistry
  • Plant Extracts / isolation & purification
  • Plant Extracts / pharmacology*
  • Rats
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Urtica dioica / chemistry*

Substances

  • Hypoglycemic Agents
  • Insulin
  • Plant Extracts
  • Glucose