Evidence for functional selectivity in TUDC- and norUDCA-induced signal transduction via α5β1 integrin towards choleresis

Sci Rep. 2020 Apr 2;10(1):5795. doi: 10.1038/s41598-020-62326-y.

Abstract

Functional selectivity is the ligand-specific activation of certain signal transduction pathways at a receptor and has been described for G protein-coupled receptors. However, it has not yet been described for ligands interacting with integrins without αI domain. Here, we show by molecular dynamics simulations that four side chain-modified derivatives of tauroursodeoxycholic acid (TUDC), an agonist of α5β1 integrin, differentially shift the conformational equilibrium of α5β1 integrin towards the active state, in line with the extent of β1 integrin activation from immunostaining. Unlike TUDC, 24-nor-ursodeoxycholic acid (norUDCA)-induced β1 integrin activation triggered only transient activation of extracellular signal-regulated kinases and p38 mitogen-activated protein kinase and, consequently, only transient insertion of the bile acid transporter Bsep into the canalicular membrane, and did not involve activation of epidermal growth factor receptor. These results provide evidence that TUDC and norUDCA exert a functional selectivity at α5β1 integrin and may provide a rationale for differential therapeutic use of UDCA and norUDCA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 11 / metabolism
  • Animals
  • Binding Sites
  • Cholagogues and Choleretics / chemistry
  • Cholagogues and Choleretics / pharmacology*
  • ErbB Receptors / metabolism
  • Integrin alpha5beta1 / chemistry
  • Integrin alpha5beta1 / metabolism*
  • Liver / drug effects
  • Liver / metabolism*
  • MAP Kinase Signaling System*
  • Male
  • Molecular Docking Simulation
  • Protein Binding
  • Rats
  • Rats, Wistar
  • Taurochenodeoxycholic Acid / chemistry
  • Taurochenodeoxycholic Acid / pharmacology*
  • Ursodeoxycholic Acid / chemistry
  • Ursodeoxycholic Acid / pharmacology*
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • ATP Binding Cassette Transporter, Subfamily B, Member 11
  • Abcb11 protein, rat
  • Cholagogues and Choleretics
  • Integrin alpha5beta1
  • Taurochenodeoxycholic Acid
  • ursodoxicoltaurine
  • Ursodeoxycholic Acid
  • ErbB Receptors
  • p38 Mitogen-Activated Protein Kinases