Methylglyoxal

About: Methylglyoxal is a research topic. Over the lifetime, 2844 publications have been published within this topic receiving 102037 citations. The topic is also known as: acetylformaldehyde & pyruvaldehyde.

The structural modification of DNA nucleosides by nonenzymatic glycation: an in vitro study based on the reactions of glyoxal and methylglyoxal with 2′-deoxyguanosine

Abstract: Methylglyoxal and glyoxal are generated from the oxidation of carbohydrates and lipids, and like d-glucose have been shown to nonenzymatically react with proteins to form advanced glycation end products (AGEs). AGEs can occur both in vitro and in vivo, and these compounds have been shown to exacerbate many of the long-term complications of diabetes. Earlier studies in our laboratory reported d-glucose, d-galactose, and d/l-glyceraldehyde formed AGEs with nucleosides. The objective of this study was to focus on purines and pyrimidines and to analyze these DNA nucleoside derived AGE adducts with glyoxal or methylglyoxal using a combination of analytical techniques. Studies using UV and fluorescence spectroscopy along with mass spectrometry provided for a thorough analysis of the nucleoside AGEs and demonstrated that methylglyoxal and glyoxal reacted with 2′-deoxyguanosine via the classic Amadori pathway, and did not react appreciably with 2′-deoxyadenosine, 2′-deoxythymidine, and 2′-deoxycytidine. Additional findings revealed that methylglyoxal was more reactive than glyoxal.

Formation of 2,5-dimethyl-4-hydroxy-3(2H)-furanone through methylglyoxal: a Maillard reaction intermediate.

Abstract: The caramel-like aroma compound, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) was quantified and verified by HPLC and GC-MS in the Maillard reaction based on methylglyoxal (MG). The reaction was performed in the 0.5 M phosphate buffer by heating MG with or without either glycine or cysteine at 120 °C for 1 h. MG alone or MG with cysteine could produce increased level of DMHF with pH increased, whereas MG with glycine had contrary trend. Experiments using a 1:1 mixture of [13C6]glucose and [12C6]glucose indicate that in the presence of glycine or cysteine, glucose skeleton kept intact during DMHF formation since a 1:1 mixture of [13C6]DMHF and [12C6]DMHF was formed. Acetylformoin was detected in the glucose with amino acid reaction system as a precursor of DMHF, while in the MG reaction systems, acetylformoin could not be identified. It is suggested different pathways of DMHF formation via MG and glucose.

The antimitochondrial action of 2-choloro-4', 4"-bis(2-imidazolin-2-yl)terephthalanilide and methylglyoxal bis(guanylhydrazone).

Abstract: Summary The polycationic drugs 2-chloro-4′, 4″-bis(2-imidazolin-2-yl)terephthalanilide (NSC 38280) 3 and methylglyoxal bis(guanylhydrazone) (MeGAG) behaveas mitochondrial poisons during therapy of the L1210 tumor. Cellular respiration is partly inhibited and the phosphorylation of isolated mitochondria is uncoupled. In common with 2,4-dinitrophenol, the drugs selectively inhibit acetate incorporation into lipid, and under limited circumstances they can abolish the cellular pools of ATP. The mitochondrial effects are: ( a ) potentiated during synergistic therapy with MeGAG and stilbamidine or hydroxystilbamidine, ( b ) abolished when the antitumor effect of MeGAG is antagonized by spermidine, and ( c ) not present during treatment with the therapeutically ineffective dimethylglyoxal bis(guanylhydrazone) or with therapeutically effective but distant congeners of NSC 38280. The tumor can compensate for the loss of its aerobic energy supply with fermentative sources of energy from the host. Antimitochondrial action thus may underlie many of the physiologic effects of these drugs, and a mitochondrial function other than the supply of ATP may be involved in their antitumor action.