Mouse mitochondrial lipid composition is defined by age in brain and muscle.
Functionality of the lipid rich mitochondrial organelle declines with increased age. Recent advances in lipidomic technologies allowed us to perform a global characterisation of lipid composition in two different tissue types and age ranges. Ultra-high performance liquid chromatography coupled with high resolution mass spectrometry was used to establish and compare mitochondrial lipidomes of brain and skeletal muscle from young (4-11 weeks old) and middle age (78 weeks old) healthy mice. In middle age the brain mitochondria had reduced levels of fatty acids, particularly polyunsaturated fatty acids, while skeletal muscle mitochondria had a decreased abundance of phosphatidylethanolamine, but a pronounced increase of triglyceride levels. Reduced levels of phosphatidylethanolamines are known to decrease mitochondrial membrane fluidity and are connected with accelerated ageing. In mitochondria from skeletal muscle we propose that increased age causes a metabolic shift in the conversion of diacylglycerol so that triglycerides predominate compared with phosphatidylethanolamines. This is the first time mitochondrial lipid content in normal healthy mammalian ageing brain and muscle has been catalogued in such detail across all lipid classes. We identify distinct mitochondrial lipid signatures that change with age, revealing tissue-specific lipid pathways as possible targets to ameliorate ageing-related mitochondrial decline.
School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, LE12 5RD, UK.
Amelia K
AK
Pollard
Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, NG7 2RD, UK.
Catharine A
CA
Ortori
Division of Animal Science, School of Biosciences, University of Nottingham, LE12 5RD, UK.
Reinhard
R
Stöger
Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, NG7 2RD, UK.
David A
DA
Barrett
School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, LE12 5RD, UK.
Lisa
L
Chakrabarti
D000375:Aging; D000818:Animals; D001923:Brain Chemistry; D008055:Lipids / Q000032:analysis*; D051379:Mice; D008928:Mitochondria / Q000737:chemistry* / Q000378:metabolism; D018482:Muscle, Skeletal / Q000737:chemistry*
D008055:Lipids
ageing; brain; global lipidomics; mitochondria; mouse; skeletal muscle