Reactive oxygen species serve as signals mediating glucose-stimulated somatostatin secretion from cultured rat gastric primary D-cells

Abstract

Somatostatin plays an important role in glucose homeostasis. It is normally secreted in response to glucose and ATP generation is believed to be the key transduction signal of glucose-stimulated somatostatin secretion (GSSS). However, in the present study, in cultured rat gastric primary D-cells, GSSS was accompanied by increases in cellular reactive oxygen species (ROS). GSSS is dependent on the cellular ROS and independently of the ATP production linked to glucose metabolism. The antioxidant, α-lipoic acid or catalase inhibitor, 3-aminotriazole can influence the intracellular calcium concentration and abolish or further elevate GSSS. It is suggested that ROS production may serve as a signal modulating the necessary Ca²⁺ recruitment for GSSS. Since somatostatin is thought to exert broad regulatory functions on gastrointestinal physiology and nutrient intake, the interaction with ROS may lead to potential targets for mediating nutrition and energy homeostasis.

Keywords::

• D-cells
• somatostatin
• ROS
• glucose-stimulated somatostatin secretion

Declaration of interest: This project supported by the National Natural Science Foundation of China (Grant No.30571347) and The National Key Technology R&D Program (2006BAD27B06) and the State Key Laboratory of food Science and Technology for Oxidant Protein, Wuxi Institute, China (Grant No.-200803). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

This paper was first published online on Early Online on 22 March 2010.