Problems of Cryobiology and Cryomedicine

Effect of chronic cold stress and dalargin on blood parameters in guinea pigs

2025-12-08T22:18:56+01:00

This study investigates the effects of the synthetic neuropeptide dalargin on hematological parameters and blood electrolyte homeostasis in guinea pigs under conditions of chronic cold stress (CCS) at 4°C over a five-day period. It was found that CCS led to a reduction in platelet count and disruption of the leukocyte profile, including an increase in band neutrophils accompanied by a decrease in segmented neutrophils, lymphocytes, and monocytes, as well as a decline in the adaptation index. Simultaneously, elevated concentrations of calcium, potassium, and chloride were observed, indicating disturbances in electrolyte balance and ionic homeostasis.

Dalargin administration prevented these changes, promoting the restoration of physiological leukocyte ratios, increasing platelet counts, and normalizing key plasma electrolyte concentrations. Moreover, an increase in the adaptation index was recorded, indicating activation of the hematopoietic system and mobilization of the organism’s adaptive potential

These findings support the potential of dalargin as an effective agent for maintaining blood system integrity, electrolyte balance, and adaptive capacity under CCS conditions.

Probl Cryobiol Cryomed. 2025; 35(3): 115—122

Effects of short-term cold exposures on blood leukocyte parameters in rats of different ages

2025-12-08T22:33:22+01:00

The short-term intermittent cold exposures (STCE) at 10 and –12°C on the ratio of leukocyte types in the blood of 6-, 12-, and 24-month-old rats, as well as the changes in integral leukocyte indices (ILIs) were studied. Under both STCE regimens, the total number of leukocytes in 6-month-old animals increased, while in 12- and 24-month-old ones it decreased, the percentage of segmented neutrophils in all age groups augmented, and that of lymphocytes reduced. The allergization and immunoreactivity indices decreased, and cellular immunity predominated (except for 24-month-old rats at –12°C). After STCE 10°C, the Garkavi adaptation index decreased in rats of all age groups, but at STCE –12°C it reduced in 6-month-old ones only. The innate immunity was activated in rats of all age groups at 10°C, but at –12° it was only in 6- and 12-month-old animals. Under both STCE regimens, the 6- and 12-month-old rats showed decreased adaptive immunity and increased inflammation. Changes in ILIs after STCE –12°C were the highest in 6-month-old animals and the lowest in 24-month-old ones.

Probl Cryobiol Cryomed. 2025; 35(3): 123—129

Features of the relationship between the chemical composition of cow's milk and its freezing point values

2025-12-08T22:45:33+01:00

This article reveals the seasonal characteristics of the formation of the most significant factors that affect the freezing point of cow's milk. The results of the generalization performed in this study on the relationship between the freezing point of milk and the content of its main components, which determine its nutritional value, can provide a significant foundation for developing organizational mechanisms to regulate milk production and implement a unified quality policy at all management levels through mathematical modeling. The chosen approach enables the ranking of basic milk quality properties, ensuring the selection of the most important ones. It has been established that an increase in the mass fraction of dry matter and lactose in milk leads to a corresponding decrease in its freezing point. Furthermore, it has been substantiated that the freezing point of milk varies throughout the year. Considering these values, we can fairly assess the degree to which milk has been adulterated with water while ensuring its high quality and safety.

Probl Cryobiol Cryomed. 2025; 35(3): 130—137

The impact of low-temperature tolerance on the environmental plasticity indicators of winter bread wheat in the context of climate change

2025-12-09T08:27:52+01:00

This study examines how low-temperature tolerance influences environmental plasticity of winter bread wheat — a critical factor for crop homeostasis amid global warming challenges. Among winter wheat genotypes graded by hypothermia tolerance, 19.0 % demonstrated the highest environmental plasticity for yield. Genotypes with superior genetic potential adaptability (identified by the lowest rank sums (rank sum = 2) of genotypic effect and regression coefficient (Oktava Odeska, Pontiyka, Zamolxe, NE 10507) yielded 128–148 % related to the check cultivar. In the winter bread wheat cultivars under investigation, there was a moderate negative correlation between freezing tolerance of winter bread wheat leaves in early spring and rank sum of genotypic effect and yield plasticity (r = –0.42; P < 0.05) and a moderate positive correlation between tolerance to critical freezing temperatures and rank sum of genotypic effect and yield plasticity (r = 0.41; P < 0.05). The selected winter bread wheat genotypes with high genetic potentials of environmental plasticity represent high-value starting materials for breeding new wheat cultivars that would be adaptable to current climatic changes.

Probl Cryobiol Cryomed. 2025; 35(3): 138—148

Storage of cereal seeds at 4 °C

2025-12-09T10:34:32+01:00

Seed longevity was studied for wheat (Triticum aestivum): var. еrythrospermum, var. lutescens spring and winter bread; spring durum wheat (Triticum durum): var. hordeiforme, var. leucurum, var. melanopus, var. alexandrinum; winter rye (Secale cereale) subsp. cereale var. vulgare; spring barley (Hordeum vulgare): var. nutans, var. erectum, var. rikotense, var. nudum, var. pallidum; maize (Zea mays) subspecies: popcorn (subsp. everta), flint corn (subsp. indurata), dent corn (subsp. indentata), semident corn (subsp. semidentata), sweet (subsp. saccharata) when stored at a temperature 4ºC and seed moisture content of 6-7%. We assessed the germination dynamics of 41 samples of these genotypes during storage for up to 10 years. For most samples, no significant differences in germination were found as compared to the initial one. In some cases, an increase in seed germination was observed after 4–8 years of storage. Variations in seed germination depending on sample genotype were tracked. The paper analyses differences in seed longevity of different cultivars of studied species and discusses the effect of low temperatures on seed longevity and expression of genes, especially those that enhance abscisic acid catabolism.

Probl Cryobiol Cryomed. 2025; 35(3): 149—156

The impact of indoline derivatives on the carbohydrate metabolism of rats within a cold stress model

2025-12-09T13:30:09+01:00

This study investigated the protective effect of 2-oxoindoline-3-glyoxylic acid derivatives and its mechanisms upon cold injury in rats.

The protective activity of 13 newly synthesized 2-oxoindoline-3-glyoxylic acid derivatives was evaluated at a dose of 12 mg/kg body weight administered intraperitoneally. One hour after administration, the physical endurance of male rats was assessed under cold stress conditions (water temperature +10 °C) with an additional load (10% of body weight) by measuring the duration of swimming (in seconds) until the appearance of complete fatigue (immersion). The results were compared to those of the reference substance ethylthiobenzimidazole at a dose of 50 mg/kg. The most effective results were observed after the administration of 2-hydroxy-2-(5-methyl-2-oxy-1,2-dihydroindol-3-ylidene)-N-phenylacetamide. In animals, serum glucose levels and carbohydrate metabolism indicators in hepatocytes (glycogen, glucose, pyruvate, lactate content and their ratio) were determined. It was established that administering 2-hydroxy-2-(5-methyl-2-oxy-1,2-dihydroindol-3-ylidene)-N-phenylacetamide significantly prolonged the duration of swimming in cold water, compared to both the control group and the group administered ethylthiobenzimidazole. Under hypothermic conditions, this compound prevented hypoglycaemia and positively affected carbohydrate metabolism in the liver, as evidenced by preserved glycogen, glucose and pyruvate content, and increased lactate levels.

Probl Cryobiol Cryomed. 2025; 35(3):157—162