Cookies help us deliver our services. By using our services, you agree to our use of cookies. More information

Munro 2013 Abstract MiP2013

From Bioblast
Munro D, Blier PU (2013) Mitochondrial membranes of the longest-lived metazoan (Arctica islandica) are lipoxidation-resistant. Mitochondr Physiol Network 18.08.

Link:

Daniel Munro

MiP2013, Book of Abstracts Open Access

Munro D, Blier PU (2013)

Event: MiPNet18.08_MiP2013

Reactive oxygen species (ROS) initiate chain reactions of lipid oxidation (lipoxidation) within biological membranes, generating detrimental breakdown products (reactive aldehydes) acting as secondary ROS. These additional ROS further contribute to the mutation load on mtDNA, and hence senescence of post mitotic tissues [1]. A membrane’s susceptibility to lipoxidation is proportional to its content in highy oxidizable PUFA and can be estimated by calculating the peroxidation index (PI) value following lipid analysis. Past researches on mammals and birds revealed inverse correlations between the PI value and the species’ longevity for skeletal muscle total phospholipids and liver mitochondria phospholipids [2].

The longest-lived metazoan, the mud clam Arctica islandica (maximum reported longevity = 507 y) offers an opportunity for a robust test of the relationship outside the traditional homeothermic taxons characterized by a much conserved physiology. Indeed bivalves experience daily to annual changes in factors known to affect membrane lipid composition in invertebrates such as temperature, salinity, pressure and pO2 which raises the question of the relative importance of adapting lipid in relation to longevity in these organisms. We compared A. islandica with four other sympatric bivalve molluscs greatly differing in longevity (Mya arenaria = 28, Spisula solidissima = 37, Mactromeris polynyma = 92, and Mercenaria mercenaria = 106 y). Using the gill tissue, we measured the PI value for mitochondrial membrane as well as for other membranes contained in cellular debris devoid of mitochondria. We found a significant negative relationship between the PI value and longevity for both biological fractions (mitochondria: R2 = 0.855, P = 0.024; cellular debris: R2 = 0.924, P = 0.009) with particularly low values for A. islandica. Furthermore, the best fit model for the relationship was exponential for mitochondria while it was linear for other cell membranes. These results suggest a generalized association between longevity and membrane PI among animals. They further suggest a relatively greater importance in adjusting the lipid composition of the mitochondrial membrane over that of other cellular membranes.

Keywords: Bivalve molluscs, Lipid composition, Lipoperoxidation, gas chromatography-mass spectrometry

O2k-Network Lab: CA Rimouski Blier PU


Labels: MiParea: mt-Membrane, mtDNA;mt-genetics, Comparative MiP;environmental MiP  Pathology: Aging;senescence  Stress:Oxidative stress;RONS  Organism: Molluscs  Tissue;cell: Lung;gill  Preparation: Isolated mitochondria 




MiP2013 

Affiliations and author contributions

Dept Biology, UQAR University, Rimouski, Canada. - Email: [email protected]

References

  1. Pamplona R (2011) Mitochondrial DNA damage in animal longevity: Insights from comparative studies. J Aging Res 807108.
  2. Hulbert AJ, Pamplona R, Buffenstein R, Buttemer WA (2007) Life and death: Metabolic rate, membrane composition, and life span of animals. Physiol Rev 87: 1175–1213.