Islet Complex Lipids: Involvement in the Actions of Group VIA Calcium-Independent Phospholipase A2 in β-Cells

Academic Article

Abstract

  • The β-isoform of group VIA calcium-independent phospholipase A 2 (iPLA2β) does not require calcium for activation, is stimulated by ATP, and is sensitive to inhibition by a bromoenol lactone suicide substrate. Several potential functions have been proposed for iPLA 2β. Our studies indicate that iPLA2β is expressed in β-cells and participates in glucose-stimulated insulin secretion but is not involved in membrane phospholipid remodeling. If iPLA 2β plays a signaling role in glucose-stimulated insulin secretion, then conditions that impair iPLA2β functions might contribute to the diminished capacity of β-cells to secrete insulin in response to glucose, which is a prominent characteristic of type 2 diabetes. Our recent studies suggest that iPLA2β might also participate in β-cell proliferation and apoptosis and that various phospholipid-derived mediators are involved in these processes. Detailed characterization of the iPLA2β protein level reveals that β-cells express multiple isoforms of the enzyme, and our studies involve the hypothesis that different isoforms have different functions.
  • Published In

  • Diabetes  Journal
  • Digital Object Identifier (doi)

    Author List

  • Ramanadham S; Song H; Bao S; Hsu FF; Zhang S; Ma Z; Jin C; Turk J
  • Volume

  • 53
  • Issue

  • SUPPL. 1