Expression of iPLA2 in human pancreatic islets and its important role in glucose-stimulated insulin secretion
Wang, R.-t.; Song, K.-y.; Shi, J.-y.; Lu, L.-s.; Yang, J.; Wang, Q.-p.; Li, K.
Zhonghua Yi Xue Za Zhi 89(20): 1426-1429
2009
ISSN/ISBN: 0376-2491 PMID: 19671340 Document Number: 633301
To assess the role of calcium-independent phospholipase A2 (iPLA2) in human pancreatic islets. The immunohistochemical analysis and Western blot were employed to examine iPLA2 expression in human pancreatic islets. Bromoenol lactone (BEL), a selective inhibitor of iPLA2, was used in a randomized controlled trial to compare its influence to glucose-stimulated insulin secretion. iPLA2 was expressed predominantly in islet cells co-stained by insulin but was barely detected in the exocrine acinar cells. Western blot results indicated that islet cells expressed an iPLA2-immunoreactive band at the 80 kDa region. Glucose-stimulated insulin secretory response was dramatically reduced in islets pretreated with BEL (0.8285 +/- 0.0803 ng x islet(-1) x h(-1)) as compared with the control (1.2264 +/- 0.0568 ng x islet(-1) x h(-1)) (P < 0.01). BEL inhibited glucose stimulated insulin secretion from isolated human islets. iPLA2 signaling plays an important role in glucose-stimulated insulin secretion under the physiological conditions.