The specific localization of advanced glycation end-products (AGEs) in rat pancreatic islets

• Main Authors: Yuta Morioka, Kiyoshi Teshigawara, Yasuko Tomono, Dengli Wang, Yasuhisa Izushi, Hidenori Wake, Keyue Liu, Hideo Kohka Takahashi, Shuji Mori, Masahiro Nishibori
• Format: Article
• Language: English
• Published: Elsevier 2017-08-01
• Series: Journal of Pharmacological Sciences
• Subjects: Advanced glycation end products (AGEs); Glyceraldehyde-derived AGEs (Glycer-AGEs); Methylglyoxal-derived AGEs (MGO-AGEs); Pancreatic alpha cells; Pancreatic beta cells
• Online Access: http://www.sciencedirect.com/science/article/pii/S1347861317301111

Advanced glycation end-products (AGEs) are produced by non-enzymatic glycation between protein and reducing sugar such as glucose. Although glyceraldehyde-derived AGEs (Glycer-AGEs), one of the AGEs subspecies, have been reported to be involved in the pathogenesis of various age-relating diseases such as diabetes mellitus or arteriosclerosis, little is known about the pathological and physiological mechanism of AGEs in vivo. In present study, we produced 4 kinds of polyclonal antibodies against AGEs subspecies and investigated the localization of AGEs-modified proteins in rat peripheral tissues, making use of these antibodies. We found that Glycer-AGEs and methylglyoxal-derived AGEs (MGO-AGEs) were present in pancreatic islets of healthy rats, distinguished clearly into the pancreatic α and β cells, respectively. Although streptozotocin-induced diabetic rats suffered from remarkable impairment of pancreatic islets, the localization and deposit levels of the Glycer- and MGO-AGEs were not altered in the remaining α and β cells. Remarkably, the MGO-AGEs in pancreatic β cells were localized into the insulin-secretory granules. These results suggest that the cell-specific localization of AGEs-modified proteins are presence generally in healthy peripheral tissues, involved in physiological intracellular roles, such as a post-translational modulator contributing to the secretory and/or maturational functions of insulin.