Preservation of integrity of the inner mitochondrial membrane after freeze-thawing and freeze-drying

Phase structures and transitions in fully hydrated diacyltrehalose

Real time X-ray diffraction was used to examine the gel bilayer to disordered bilayer phase transition in fully hydrated dipalmitoyltrehalose. The L beta to L alpha phase transition was shown to proceed via a second-order thermodynamic process involving incommensurate mesophase bilayer repeat structures and the formation of an intermediate rectangular acyl chain packing subcell. This phenomenon has only been previously shown to occur for dihexadecylphosphatidylcholine (DHPC) and dipalmitoylphosphatidylcholine (DPPC) dihydrates undergoing stepwise (i.e., noncontinuous) temperature changes. It can thus be inferred that the presence of trehalose-trehalose intra-bilayer interactions is a sufficient condition to modify the acyl chain structural rearrangements within the bilayer as a function of temperature.

Activity of ATP synthetase complex after low temperature treatment or freeze-drying of mitochondria isolated from skeletal muscles

The influence of freezing, thawing, or freeze-drying on ATP synthetase complex of isolated skeletal muscle mitochondria was studied. Cooling to -60 or to -196 degrees C and rapid thawing did not change activity significantly. Slow warming stimulated the release of latent ATP-ase activity and decreased ATP synthesis. These changes were more pronounced after freeze-drying.

Preservation of integrity of the inner mitochondrial membrane after freeze-thawing and freeze-drying

The results of this paper illustrate that trehalose partially preserves inner mitochondrial membrane integrity after freeze-thawing and freeze-drying with subsequent rehydration in water. The 2,4-dinitrophenol stimulation of ATPase activity was used as a criterion for membrane integrity. The results show that ATPase activity of lyophilized-rehydrated mitochondria was stimulated up to two to three times.