[Methylglyoxal--a test for impaired biological functions of exotrophy and endoecology, low glucose level in the cytosol and gluconeogenesis from fatty acids (a lecture)].
In philogenesis, due to the failure to store a great deal of carbohydrates in vivo as glycogen, all animal species began synthesizing from glucose palminitic fatty acid and depositing it as triglycerides. During biological dysfunction of exotrophy (long starvation, early postnatality, hibernation), cells also accomplish a reverse synthesis of glucose from fatty acids under aerobic conditions. Under physiological conditions, acetyl-CoA that is converted to malate and pyruvate in the glyoxalate cycle is a substrate of glyconeogenesis. Under pathological conditions of hypoxia and deficiency of macroerges, gluconeogenesis occurs without ATP consumption through the methylglyoxal pathway when used as a substrate of ketone bodies via the pathway: butyric acid (butyrate) --> beta-hydroxybutyrate --> acetoacetate --> acetone --> acetol --> methylglyoxal --> S-D-lactol-glutathione --> D-lactate --> pyruvate --> D-lactate. Under physiological conditions, this gluconeogenesis pathway does not function. We believe that with low glucose levels in the cell cytosole (glycopenia), under pathological conditions of hypoxia and due to failure to mitochondria to oxidize fatty acids, gene expression and gluconeogenesis occur through the methylglyoxal pathway. At the same time, the cytosol, intercellular environment, and plasma shows the elevated levels of methylglyoxal and D-lactate that it is converted to by the action of glyoxalases I and II. Under pathological conditions, glycopenia develops in starvation, diabetes, and metabolic acidosis, neoplasms, renal failure, and possibly, metabolic syndrome. The chemical interaction of methylglyoxal with the amino acid residues of lysine and arginine results in the denaturation of circulating and structurized proteins via carbonylation--glycosylation.
Titov
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VN
Dmitriev
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LF
Krylin
V A
VA
Dmitriev
V A
VA
D000818:Animals; D003600:Cytosol / Q000378:metabolism*; D003920:Diabetes Mellitus / Q000175:diagnosis / Q000378:metabolism; D016883:Diabetic Ketoacidosis / Q000175:diagnosis / Q000378:metabolism; D004734:Energy Metabolism; D005227:Fatty Acids / Q000378:metabolism*; D005943:Gluconeogenesis; D005947:Glucose / Q000096:biosynthesis*; D006801:Humans; D007657:Ketone Bodies / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism; D009369:Neoplasms / Q000175:diagnosis / Q000378:metabolism; D009691:Nucleic Acid Denaturation; D011489:Protein Denaturation; D011765:Pyruvaldehyde / Q000032:analysis / Q000378:metabolism*; D051437:Renal Insufficiency / Q000175:diagnosis / Q000378:metabolism
D005227:Fatty Acids; D007657:Ketone Bodies; D019344:Lactic Acid; D011765:Pyruvaldehyde; D005947:Glucose