α,β-Unsaturated Aldehydes Accelerate Oxymyoglobin Oxidation

Abstract

This study investigates the potential basis for enhancement of oxymyoglobin (OxyMb) oxidation by lipid oxidation products. Aldehydes known to be formed as secondary lipid oxidation products were combined with OxyMb in aqueous solution at 37 degrees C and pH 7.4. Metmyoglobin (MetMb) formation was greater in the presence of alpha,beta-unsaturated aldehydes than their saturated counterparts of equivalent carbon chain length. Additionally, increasing chain length from hexenal through nonenal resulted in increased MetMb formation (P < 0.05). Electrospray ionization mass spectrometry (ESI-MS) revealed that OxyMb incubated with 4-hydroxynonenal (HNE) at pH 7.4 at 37 degrees C yielded myoglobin molecules adducted with one to three molecules of HNE from 0.5 to 2 h of incubation, respectively. A prooxidant effect of HNE was noted at pH 7.4 but was not apparent at pH 5.6 when compared to the control (P < 0.05). This appeared to be due to rapid OxyMb autoxidation at this pH compared to pH 7.4. ESI-MS demonstrated that adduction of HNE to OxyMb occurred at pH 5.6. This research demonstrates that alpha, beta-unsaturated aldehydes accelerate OxyMb oxidation and appear to do so via covalent attachment.

Effect of α-tocopherol tissue levels on beef quality

“…Faustman et al (1989), based on earlier results from Greene (1969), suggested that antioxidants inhibit oxidation by protecting the pigment from reaction with oxidation intermediates such as free radicals. Vitamin E could inhibit lipid oxidation and consequently a reaction with secondary oxidation products such as a-, b-unsaturated aldehydes (Faustman et al, 1999). However, a more recent study, by O'Grady et al (2001), which has been supported by Monahan et al (2005), indicated that in an oxidizing muscle system the depletion of dissolved oxygen as a result of lipid oxidation is the primary cause of oxymyoglobin oxidation.…”

Effect of 4-hydroxy-2-nonenal treatment on the IgE binding capacity and structure of shrimp (Metapenaeus ensis) tropomyosin

“…As a monocarbonyl compound, HNE can bind oxidatively with the side chains of certain amino acids, resulting in conformational changes of the protein. Moreover, the strong electrophilic nature of the C-3 carbon makes HNE highly reactive with cellular nucleophiles, of which the histidine residue in proteins has been the commonly reported target (Alderton, Faustman, Liebler, & Hill, 2003;Faustman, Liebler, McClure, & Sun, 1999;Suman, Faustman, Stamer, & Liebler, 2007;Uchida & Stadtman, 1992). It is reasonable to hypothesize that the structural transformation of proteins caused by these oxidative modifications might be the direct reason for their allergenicity.…”

Detection of 4-hydroxy-2-nonenal adducts of turkey and chicken myoglobins using mass spectrometry

“…HNE was reported to accelerate oxidation of tuna (Lee, Joo, Alderton, Hill, & Faustman, 2003), equine (Faustman, Liebler, McClure, & Sun, 1999), bovine and porcine (Suman et al, 2007) Mbs. Faustman et al (1999) noted that formation of Mb-aldehyde adducts occurred concomitantly with OxyMb oxidation.…”

“…Faustman et al (1999) noted that formation of Mb-aldehyde adducts occurred concomitantly with OxyMb oxidation. The latter finding was confirmed in beef and pork Mb reacted with HNE Suman et al, 2007).…”

“…In contrast, Suman et al (2007) reported only mono-adducts of HNE with porcine Mb under similar conditions. The strong electrophilic nature of the C-3 carbon makes HNE highly reactive with cellular nucleophiles; histidine residues have been commonly reported targets in proteins Faustman et al, 1999;Suman et al, 2007;Uchida & Stadtman, 1992).…”