Hempenstall 2012 Mech Ageing Dev
| Hempenstall S, Page MM, Wallen KR, Selman C (2012) Dietary restriction increases skeletal muscle mitochondrial respiration but not mitochondrial content in C57BL/6 mice. Mech Ageing Dev 133: 37-45. |
Β» [[Has info::PMID:22212415]]
Hempenstall S, Page MM, Wallen KR, Selman C (2012) Mech Ageing Dev
Abstract: Dietary restriction (DR) is suggested to induce mitochondrial biogenesis, although recently this has been challenged. Here we determined the impact of 1, 9 and 18 months of 30% DR in male C57BL/6 mice on key mitochondrial factors and on mitochondrial function in skeletal muscle, relative to age-matched ad libitum (AL) controls. We examined proteins and mRNAs associated with mitochondrial biogenesis and measured mitochondrial respiration in permeabilised myofibres using high resolution respirometry. 30% DR, irrespective of duration, had no effect on citrate synthase activity. In contrast, total and nuclear protein levels of PGC-1Ξ±, mRNA levels of several mitochondrial associated proteins (Pgc-1Ξ±, Nrf1, Core 1, Cox IV, Atps) and cytochrome c oxidase content were increased in skeletal muscle of DR mice. Furthermore, a range of mitochondrial respiration rates were increased significantly by DR, with DR partially attenuating the age-related decline in respiration observed in AL controls. Therefore, DR did not increase mitochondrial content, as determined by citrate synthase, in mouse skeletal muscle. However, it did induce a PGC-1Ξ± adaptive response and increased mitochondrial respiration. Thus, we suggest that a functionally 'efficient' mitochondrial electron transport chain may be a critical mechanism underlying DR, rather than any net increase in mitochondrial content per se. β’ Keywords: Dietary restriction
β’ O2k-Network Lab: UK Aberdeen Selman C
Labels:
Stress:z in prep Organism: Mouse Tissue;cell: Skeletal Muscle Preparation: Permeabilized Tissue Enzyme: z in prep, Marker Enzyme Regulation: z in prep
HRR: Oxygraph-2k
