Phospholipid peroxidation: lack of effect of fatty acid pairing.
Lipids
; 47(5): 451-60, 2012 May.
Article
em En
| MEDLINE
| ID: mdl-22271423
ABSTRACT
Phospholipids where both fatty acids are polyunsaturated are very rare. Most organisms prefer to couple their polyunsaturated fatty acids (PUFA) with either a saturated (SAT) or a monounsaturated (MUFA) fatty acid. This study examined if these natural couplings are there to protect PUFA from themselves. Specifically, does the coupling of PUFA to SAT or MUFA reduce the potential for increased rates of peroxidation by shrouding these highly peroxidisable fatty acids with less peroxidisable fatty acids? The influence of head group was examined by using the two most common phospholipids found in vertebrate membranes i.e. phosphatidylcholine and phosphatidylethanolamine species. Fatty acid pairings included 160/182 versus 182/182 and 160/226 versus 226/226. All phospholipids were incorporated into liposomes that were matched for their total PUFA content i.e. 25% PUFA/PUFA or 50% SAT/PUFA with phosphatidylcholine 160/160 used as the background phospholipid. An iron initiator (Fe²âº/H2O2) was used to induce peroxidation and lipid hydroperoxide production was used to measure peroxidation. The results show that coupling of PUFA together on the same molecule does not increase peroxidation rates and therefore does not support the proposed hypothesis. The lower than expected levels of peroxidation measured for some phospholipid species (e.g. PtdEtn 226/226) is possibly due to the partitioning of these molecular species into the inner leaflet of the bilayer.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fosfolipídeos
/
Peroxidação de Lipídeos
/
Ácidos Graxos Insaturados
Idioma:
En
Revista:
Lipids
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Austrália