Low fatty acid unsaturation and maximun life span

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Can anyone explain the meaning of the following abstract? Access to

the full text would be very useful. More important: how should this

information,leaving the more theorical aspects aside, if

possible(...)translate into CRON practice? Does it necessarily follow

that some (or all?) dietary PUFA (even fish oils? these being highly

unsaturated LCF)are counter-productive in terms of longevity when

considered from the point of view of the free radical theory of aging?

Would not added unsaturated oils overwhelm or create imbalances in

this system whereby the process of FA unsaturation is kept to a minimum?

In the dark again

Low fatty acid unsaturation: a mechanism for lowered lipoperoxidative

modification of tissue proteins in mammalian species with long life spans.

Pamplona R, Portero-Otin M, Riba D, Requena JR, Thorpe SR,

- M, Barja G.

Department of Basic Medical Science, University of Lleida, Spain.

Carbonyl compounds generated by the nonenzymatic oxidation of

polyunsaturated fatty acids react with nucleophilic groups in

proteins, leading to their modification. It has not been tested

whether fatty acid unsaturation is related to steady-state levels of

lipoxidation-derived protein modification in vivo. A low fatty acid

unsaturation, hence a low protein lipoxidation, in tissues of

longevous animals would be consistent with the free radical theory of

aging, because membrane lipids increase their sensitivity to oxidative

damage as a function of their degree of unsaturation. To evaluate the

relationship between fatty acid composition, protein lipoxidation, and

maximum life span (MLSP), we analyzed liver fatty acids and proteins

from seven mammalian species, ranging in MLSP from 3.5 to 46 years.

The results show that the peroxidizability index of fatty acids and

the sensitivity to in vitro lipid peroxidation are negatively

correlated with the MLSP. Based on gas chromatography and mass

spectroscopy analyses, liver proteins of all these species contain

malondialdehyde-lysine and Nepsilon-carboxymethyllysine adducts, two

biomarkers of protein lipoxidation. The steady-state levels of

malondialdehyde-lysine and Nepsilon-carboxymethyl lysine are directly

related to the peroxidizability index and inversely related to the

MLSP. We propose that a low degree of fatty acid unsaturation may have

been selected in longevous mammals to protect their tissue lipids and

proteins against oxidative damage while maintaining an appropriate

environment for membrane function.

PMID: 10843345 [PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=PubMed & list_uids=1\

0843345 & dopt=Abstract