Cold Shock Injury Research Articles

Changes in free amino acid composition in haemolymph of larvae of the wax moth, Galleria mellon ella L., during cold acclimation

1. 1. Free amino acids were analysed in the haemolymph of Galleria mellonella larvae by HPLC chromatography with o-phthaldialdehyde (OPA)-l-thio-β- d-glucose as derivatization agent. 2. 2. Fourteen primary amino acids were detected among which glutamine, alanine, γ-aminobutyric acid (GABA) and glycine predominated and constituted 67.7% of the amino acids found. 3. 3. The concentration of GABA increased significantly with the age of larvae entering the wandering phase and reached a maximum during metamorphosis. 4. 4. Analysis of cold-acclimated larvae revealed a net increase of free primary amino acids from 96 to 151.8 μmol/ml during consecutive acclimation to 0°C within 20 days and to 205.4μmol/ml during cold shock injury at 0°C (3 hr). 5. 5. The bulk of this increase was accounted for by alanine, glycine, phenylalanine and lysine.

A rapid cold-hardening response protecting against cold shock injury in Drosophila melanogaster

In studies of insect cold-hardiness, the supercooling point (SCP) is defined as the temperature at which spontaneous nucleation of body fluids occurs. Despite having an SCP of -20 degrees C, adults of Drosophila melanogaster did not survive exposure to -5 degrees C, which suggests that cold shock causes lethal injury that is not associated with freezing. If, however, flies were chilled at 5 degrees C, for as little as 30 min, approximately 50% of the flies survived exposure to -5 degrees C for 2h. This capacity to cold-harden rapidly was greatest in 3- and 5-day-old adults. The rapid cold-hardening response was also observed in larvae and pupae: no larvae survived 2 h of exposure to -5 degrees C, whereas 63% pupariated if chilled at 5 degrees C before subzero exposure. Similarly, although exposure of pupae to -8 degrees C was lethal, if pre-chilled at 5 degrees C 22% eclosed. This extremely rapid cold-hardening response may function to allow insects to enhance cold-tolerance in response to diurnal or unexpected seasonal decreases in environmental temperature.

Cold shock injury is a significant factor in freezing injury: A position for

Cold shock injury is a significant factor in freezing injury: A position for

Cold shock injury is a significant factor in freezing injury: A position against

Cold shock injury is a significant factor in freezing injury: A position against

Multifaceted freezing injury in human polymorphonuclear cells at high subfreezing temperatures

Extracellular freezing injury at high subzero temperatures in human polymorphonuclear cells (PMNs) was studied with a cryomicroscope, electron microscope, and functional assays (phagocytosis, microbicidal activity, and chemotaxis). There are at least four major factors in freezing injury: osmotic stress, chilling, cold shock, and dilution shock. Extracellularly frozen PMNs lose functions when cooled to −2 °C without a cryoprotectant. Cells lose volume on freezing to the same degree as in hypertonic exposure. PMNs have a minimum volume to which they can shrink without injury. Greater dehydration produces irreversible injury to cellular functions, and cells eventually collapse under high osmotic stress. Chilling sensitivity is seen in slowly chilled, supercooled PMNs below −5 °C: at −7 °C, functions are lost in 1 h. This injury can be prevented by the addition of Me 2SO but not glycerol. Me 2SO does not, however, prevent cold shock (injury due to rapid cooling), which is seen during cooling at 10 °C/min to −14 °C, but not during slow cooling at 0.5 °C/min. One of the problems of using glycerol as a cryoprotectant stems from the high sensitivity of PMNs to dilution shock during the dilution or removal of glycerol.

Cold shock injury in Tetrahymena pyriformis

The ciliated protozoan Tetrahymena pyriformis has been used to study the biochemistry of cellular injury induced by rapid cooling (cold shock). Cellular viability was found to depend on the time and temperature of cold exposure, and the rate of cooling. During cooling to −7.5 °C, in the absence of ice, an optimal rate of cooling of 2.5 °C min −1 was observed; at both faster and slower cooling the recovery decreased. Following acclimation at a reduced temprature (10 °C) the viability following rapid cooling was significantly different from that of cultures maintained at 20 °C. Analysis of the phospholipid fatty acids from cells grown at 10 °C demonstrated that, at the reduced temperature, there was an increase in the average degree of fatty acyl unsaturation. Cold-shock injury in Tetrahymena is associated with membrane thermotropic events which are determined by temperature per se, whereas viability is a function of the rate of cooling. A hypothesis of injury is presented in which the presence of gel-phase lipid within the membrane is not the critical event, but it is the pattern of nucleation within the membrane which ultimately determines the extent of cellular injury.

Role of cytoplasmic proteins in cold shock injury of Amoeba

Strains of Amoeba have been used to study the mechanisms of cellular injury induced by rapid cooling (cold shock). Cell viability was found to depend on the time and temperature of cold exposure, on the rate of cooling and on the morphology of the cells prior to chilling. All strains underwent a granuloplasmic contraction following undercooling to −10 °C, although its extent varied; strains most damaged by cold shock exhibited the most violent cytoplasmic contractions. Cryomicroscopy demonstrated that the cellular contraction occurred upon rewarming, not during cooling. Cells damaged by cold shock were osmotically responsive, demonstrating that irreversible damage to the plasmalemma does not account for the phenomenon. Several compounds protected Amoeba against cold shock injury, glycerol and glucose being the most effective. With glycerol an optimum rate of cooling was observed upon cooling to −10 °C, at both faster and slower cooling rates damage increased. The state of cellular actin in control cells and following cold shock was monitored by the DNase 1 inhibition assay and by electron microscopy. A comparatively “cold shock resistant” strain of A. proteus was found to contain less total actin per unit cellular protein than the more “sensitive” Amoeba sp. strain Bor. In the Bor strain a cold-induced aggregation of cytoplasmic filaments was evident in electron micrographs, presumably a crosslinking of preexisting F-actin.

Effect of Cold Shock after Thawing on Acrosomal Maintenance and Motility of Bovine Spermatozoa Frozen in Plastic Straws

Abstract Two experiments were conducted to determine the effects of thawing rate and post-thaw cold shock on survival of bull spermatozoa diluted in skim milk and packaged in .3-ml Continental U.S. straws. Average acrosomal maintenance and progressive spermatozoal motility during post-thaw incubation for 0, 3, and 6 h at 37 C were considerably higher for straws thawed rapidly in warm water at 3 5 C, whether or not exposed to cold shock at 5 C after thawing, than for straws thawed slowly in 5-C iced water. There was no evidence of cold shock damage when thawing time at 35 C was restricted (10 s) to prevent the temperature of the thawed semen from rising above 5 C. However, cold shock injury occurred when seminal temperature during thawing was permitted to rise above 5 C (23 and 35 C) before the straws were placed in iced water. Cold shock injury was more pronounced for acrosomal retention than for motility of sperm. Greatest damage to acrosomal maintenance occurred when the post-thaw temperature of the semen was lowered quickly from 35 to 5 C; retained acrosomes were reduced from 67.7% for control straws thawed at 35 C/80 s to 57.9% for straws plunged into a 5 C iced bath for 30 s after being thawed in the same manner. Regardless of thawing method, caution should be exercised to minimize the exposure of thawed straws and inseminating devices to cold.

Cold Shock Lethality and Injury in Clostridium perfringens

Several observations have been made in regard to cold shock lethality of Clostridium perfringens: (i) loss of viability was not consequence of exposure of the cells to air; (ii) stationary-phase cells were much more resistant to cold shock at 4 C than exponential-phase cells; (iii) at 4 C 96% of an initial population of exponential-phase cells was killed upon cold shock and 95% of the remaining population was killed within 90 min of continued exposure at 4 C; (iv) the minimal temperature differential for detectable cold shock lethality was between 17 and 23 C, and the maximum beyond which lethality was not appreciably increased was between 28 and 33 C. Up to 75% of viable cold-shocked cells were injured, as demonstrated by cold shocking late exponential-phase cells at 10 C and using differential plating procedure for recovery. Repair of injury was temperature dependent, and occurred in a complex medium and 0.1% peptone but not water. Nalidixic acid, chloramphenicol, and rifampin did not inhibit repair of injury.