X-Message-Number: 12178 Date: Fri, 23 Jul 1999 09:34:17 -0700 (PDT) From: Doug Skrecky <> Subject: increasing resistance to dehydration Authors Gilles R. Bourdouxhe-Housiaux C. Colson P. Houssier C. Institution Laboratory of Animal Physiology, University of Liege, Belgium. Title Effect of compensatory organic osmolytes on resistance to freeze-drying of L929 cells and of their isolated chromatin. Source Comparative Biochemistry & Physiology. Part A, Molecular & Integrative Physiology. 122(1):145-55, 1999 Jan. Abstract (1) Compensatory organic osmolytes are stabilizers of macromolecular structures. During acclimation to dehydration or high salinity, they accumulate in cells and effectively protect them against disruption that might otherwise result from increased inorganic ion concentrations. (2) Circular and electric dichroism, analysis of the kinetics of digestion by micrococcal nuclease, and UV spectra between 190 and 305 nm were used to investigate the resistance to dehydration upon freezing or freeze-drying that could confer such compounds to chromatin isolated from cultured L929 cells. Some work was also done on intact cells in vivo. (3) Sorbitol, sucrose, and trehalose appear to protect isolated chromatin very effectively; proline is less effective. (4) These compounds also effectively protect chromatin from the disrupting effects of NaCl. (5) Cells loaded and grown with sorbitol, sucrose, or proline can tolerate larger decreases in hydration than control cells. They cannot, however, tolerate complete dehydration. Additional comment by poster: Further work by this team is apparently in progress testing the effect of other polyols on increasing dehydration resistance. This may have some implications for cryonics as with sufficient dehydration freezing would result in vitrification. Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=12178