X-Message-Number: 18353 Date: Sun, 13 Jan 2002 20:36:37 -0800 (PST) From: Doug Skrecky <> Subject: Some information on intracellular trehalose Quick summary by the poster: Intracellular trehalose confers increased dehydration tolerance in mamalian cells. Freezing stresses cells partly by dehydration. Vitrification solutions also stress cells by dehydration. IMHO, intracellular loading of trehalose in transplant organs slated for vitrification, is likely to significantly improve cellular viability. Beneficial Effect of Microinjected Trehalose on the Cryosurvival of Human Oocytes Fertility and Sterility 77(1): 152-158 January 2002 Objective: To determine the effectiveness of trehalose as an intracellular cryoprotectant of human oocytes. Intervention(s): Discarded human oocytes, obtained from IVF patients, were randomly distributed into three groups; control group (no trehalose), extracellular trehalose group (0.5 M extracellular trehalose), and intracellular trehalose group (0.15 M intra- and 0.5 M extracellular trehalose). Trehalose was introduced into oocytes by microinjection. The oocytes in each group were cooled to different temperatures (i.e., -15C, -30C, and -60C) at rate of 1C/minute and thawed at ambient air temperature. Survival was examined after overnight culture. Results(s): The majority of oocytes in the intracellular trehalose group survived cooling to -15C (63%), -30C (53%), and -60C (66%). In contrast, only a small number of oocytes in both the control (13%) and extracellular trehalose group (22%) survived cooling to -15C, while all oocytes degenerated when cooled to -30C and -60C. Conclusion(s): Small amounts of intracellular trehalose in the absence of any other cryoprotectant provide a significant protection against freeze-associated stresses. Our results suggest that sugars such as trehalose should be considered as intracellular cryoprotectants for cryopreservation of human oocytes. Also of interest: Survival of the Cryptobiotic Eutadigrade Adorybiotus Coronifer During Cooling to -196C: Effect of Cooling Rate, Trehalose Level, and Short-Term Acclimation Cryobiology 29: 125-130 1992 Trehalose: A Cryoprotectant that Enhances Recovery and Preserves Function of Human Pancreatic Islets After Long-Term Storage Diabetes 46: 519-523 1997 Role of Saccharides on Lung Preservation Transplantation 68(1): 110-117 July 15, 1999 Intracellular Trehalose Improves the Survival of Cryopreserved Mammalian Cells Nature Biotechnology 18: 163-167 February 2000 Trehalose Expression Confers Desiccation Tolerance on Human Cells Nature Biotechnology 18: 168-171 February 2000 Intracellular Trehalose Improves Osmotolerance but not Desiccation Tolerance in Mammalian Cells FEBS Letters 487: 199-202 December 2000 Human Platelets Loaded with Trehalose Survive Freeze-Drying Cryobiology 42: 79-87 2001 Desiccation Tolerance in Human Cells Cryobiology 42: 207-217 2001 Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=18353