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Getting the message across: pathophysiology and signaling via receptors for polypeptide hormones and proteinases

Morley D Hollenberg1

  • 1Department of Physiology & Pharmacology and Department of Medicine, University of Calgary Faculty of Medicine, Calgary, AB, Canada T2N 4N1. mhollenb@ucalgary.ca

Clinical and Investigative Medicine. Medecine Clinique Et Experimentale
|April 8, 2010
PubMed

Insights

Proteinases generate hormone-like signals, activating unique proteinase-activated receptors (PARs). These receptors play roles in inflammation and offer potential therapeutic targets for conditions like arthritis and colitis.

Area of Science:

  • Biochemistry
  • Cell Signaling
  • Pharmacology

Background:

  • Proteinases play a critical role in cellular communication by generating signaling molecules.
  • The discovery of proteinase-activated receptors (PARs) evolved from studies on peptide hormone interactions.
  • PARs represent a unique class of G-protein-coupled receptors activated by proteolysis.

Purpose of the Study:

  • To provide an overview of proteinase-mediated cell signaling.
  • To explore the discovery and unique activation mechanism of PARs.
  • To discuss the physiological and therapeutic implications of PARs in inflammatory diseases.

Main Methods:

  • Review of historical research on proteinase-ligand interactions.
  • Examination of the tethered ligand activation mechanism of PARs.
  • Analysis of literature on PARs in inflammatory disorders.

Main Results:

  • Proteinases generate diverse hormone-like signals.
  • PARs possess a unique tethered ligand activation mechanism.
  • PARs are implicated in inflammatory conditions such as arthritis and colitis.

Conclusions:

  • Proteinases are key regulators of cell signaling through PARs and other pathways.
  • PARs have significant physiological and pathophysiological roles, particularly in inflammation.
  • Targeting PARs presents a promising therapeutic strategy for inflammatory diseases.

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