title: Bound malondialdehyde in foods: bioavailability of N,N'-di-(4-methyl-1,4-dihydropyridine-3,5-dicarbaldehyde)lysine.
abstract: Reactions between lipid peroxidation products and proteins in foods have detrimental nutritional effects, most importantly, losses of essential amino acids. One of the major products of the reaction of malondialdehyde and alkanals with amino groups are 4-substituted 1,4-dihydropyridine-3,5-dicarbaldehyde derivatives. The product of the reaction of lysine with malondialdehyde and acetaldehyde, N,N'-di-(4-methyl-1,4-dihydropyridine-3,5-dicarbaldehyde)lysine (MDDL), has been synthesized and used for in vitro and in vivo bioavailability studies. Release of free lysine did not occur in incubations of MDDL with tissue homogenates. After oral administration of radioactively labeled MDDL, radioactivity was only recovered in feces. Radioactivity was not incorporated into hepatic microsomes after intraperitoneal administration, which would have indicated release of available lysine. These results show that MDDL is a form of unavailable lysine, because it is not metabolized to free lysine and cannot be absorbed from the gut. Thus, formation of this derivative in foods would result in loss of available lysine.
authors.affiliation: Instituto de la Grasa (Consejo Superior de Investigaciones Científicas), Avenida Padre García Tejero, 4, 41012 Sevilla, Spain. jgiron@cica.es
authors.forename: Julio
authors.initials: J
authors.lastname: Girón-Calle
authors.forename: Manuel
authors.initials: M
authors.lastname: Alaiz
authors.forename: Francisco
authors.initials: F
authors.lastname: Millán
authors.forename: Valentina
authors.initials: V
authors.lastname: Ruiz-Gutierrez
authors.forename: Eduardo
authors.initials: E
authors.lastname: Vioque
mesh_terms: D000447:Aldehydes / Q000737:chemistry / Q000493:pharmacokinetics*; D000818:Animals; D002250:Carbon Radioisotopes; D005504:Food Analysis; D007413:Intestinal Mucosa / Q000201:enzymology; D007668:Kidney / Q000201:enzymology; D008099:Liver / Q000201:enzymology; D008239:Lysine / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000493:pharmacokinetics*; D008297:Male; D008315:Malondialdehyde / Q000032:analysis / Q000737:chemistry*; D008862:Microsomes, Liver / Q000737:chemistry / Q000378:metabolism; D011725:Pyridines / Q000737:chemistry / Q000493:pharmacokinetics*; D051381:Rats; D017208:Rats, Wistar; D014316:Tritium
chemical_list: D000447:Aldehydes; D002250:Carbon Radioisotopes; C495620:N,N'-di-(4-methyl-1,4-dihydropyridine-3,5-dicarbaldehyde)lysine; D011725:Pyridines; D014316:Tritium; D008315:Malondialdehyde; D008239:Lysine