Schiff bases of putrescine with methylglyoxal protect from cellular damage caused by accumulation of methylglyoxal and reactive oxygen species in Dictyostelium discoideum

• Published in: The international journal of biochemistry & cell biology 2017-05, Vol.86, p.54-66
• Main Authors: Park, Seong-Jun, Kwak, Min-Kyu, Kang, Sa-Ouk
• Format: Article
• Language: English
• Subjects: Cell Cycle - drug effects; Cell Proliferation - drug effects; Cell Survival - drug effects; Cytoprotection - drug effects; Dictyostelium - cytology; Dictyostelium - drug effects; Dictyostelium - metabolism; Dictyostelium discoideum; Methylglyoxal; Ornithine decarboxylase; Polyamine; Putrescine; Putrescine - chemistry; Putrescine - pharmacology; Putrescine-methylglyoxal Schiff base; Pyruvaldehyde - chemistry; Pyruvaldehyde - metabolism; Reactive Oxygen Species - metabolism; Schiff Bases - chemistry
• ISSN: 1357-2725; 1878-5875
• DOI: 10.1016/j.biocel.2017.03.011

•Polycationic putrescine (PUT) is essentially required for Dictyostelium discoideum growth.•PUT regulates cellular methylglyoxal (MG) and reactive oxygen species (ROS) in the presence of glutathione (GSH).•Cellular MG and ROS accumulation in PUT-depleted cells cause G1 arrest of the cell cycle.•Schiff bases between PUT and MG are confirmed by UV–vis spectroscopy and liquid chromatography-mass spectrometry.•Cellular PUT-MG Schiff base levels are determined in PUT- and GSH-deficient cells. Polyamines protect protein glycation in cells against the advanced glycation end product precursor methylglyoxal, which is inevitably produced during glycolysis, and the enzymes that detoxify this α-ketoaldehyde have been widely studied. Nonetheless, nonenzymatic methylglyoxal-scavenging molecules have not been sufficiently studied either in vitro or in vivo. Here, we hypothesized reciprocal regulation between polyamines and methylglyoxal modeled in Dictyostelium grown in a high-glucose medium. We based our hypothesis on the reaction between putrescine and methylglyoxal in putrescine-deficient (odc−) or putrescine-overexpressing (odcoe) cells. In these strains, growth and cell cycle were found to be dependent on cellular methylglyoxal and putrescine contents. The odc− cells showed growth defects and underwent G1 phase cell cycle arrest, which was efficiently reversed by exogenous putrescine. Cellular methylglyoxal, reactive oxygen species (ROS), and glutathione levels were remarkably changed in odcoe cells and odc̄ cells. These results revealed that putrescine may act as an intracellular scavenger of methylglyoxal and ROS. Herein, we observed interactions of putrescine and methylglyoxal via formation of a Schiff base complex, by UV–vis spectroscopy, and confirmed this adduct by liquid chromatography with mass spectrometry via electrospray ionization. Schiff bases were isolated, analyzed, and predicted to have molecular masses ranging from 124 to 130. We showed that cellular putrescine–methylglyoxal Schiff bases were downregulated in proportion to the levels of endogenous or exogenous putrescine and glutathione in the odc mutants. The putrescine–methylglyoxal Schiff base affected endogenous metabolite levels. This is the first report showing that cellular methylglyoxal functions as a signaling molecule through reciprocal interactions with polyamines by forming Schiff bases.