The use of pectins as part of a cryoprotective solution for long-term storage of human platelet concentrates.

BACKGROUND: Pectins have unique properties and great potential to become an indispensable component of cryoprotective environment for platelet freezing. OBJECTIVE: To investigate the possibility of including pectins (apple pectin AU-701, tanacetan) into the composition of a cryoprotective solution for platelets during low-temperature storage. MATERIALS AND METHODS: Samples of platelet concentrates (PC) were frozen under the protection of complex solutions and stored in an electric freezer at -80 degree C for 1 and 6 months. RESULT: The study showed that of the basic cryoprotectants, the best effect in the preservation of PC was with dimethylacetamide (DMAC). The use of pectins as an additive to the base solution of DMAC statistically improves the preservation of PC after exposure to low temperatures (-80 degree C) for 30 and 180 days. CONCLUSIONS: We conclude that DMAC is more promising as a basis for the development of a new combined cryoprotectant for PC freezing. Moreover, the chemical structure of pectin determines the level of its cryoprotective action in relation to the preservation of PC. doi.org/10.54680/fr22610110312.

Application of Pectin from Aloe arborescens Mill. to the Cryopreservation of Human Leukocyte Cell Suspensions.

BACKGROUND: The molecular weight (MW) of pectic polysaccharide АА3 equal to 150 kDa and its structure suggest that it has a non-permeating protector action. OBJECTIVE: To study the ability of low methylesterified galacturonan АА3, extracted from Aloe arborescens Mill., to influence the cryoprotective properties of the refrigerant in the cryopreservation of leukocytes (-20°Ð¡, -80°Ð¡). METHODS: Pectic polysaccharide АА3 was extracted from fresh leaves using a 0.7% (w/w) solution of ammonium oxalate. The cryoscopic method was used to study its ability in different concentrations (0.1-1% w/v) in a mixture with glycerol to change the osmolarity and freezing temperature of the venous blood. Venous blood was protected with a comprehensive cryopreservative solution (3.5 % glycerol + 0.1 % pectic polysaccharide АА3) and stored at -20°C and -80°C for 1 and 7 days. RESULT: The cryoprotective properties of glycerol solution (3.5%) containing AA3 at 0.1 to 1.0% led to a decrease in the osmolarity of venous blood and accelerated the process of water freezing. So, these solutions act as nucleators. A solution of AA3 (0.1%) and glycerol (3.5%) improves the morphological preservation of granulocytes, resistance of cell membranes to eosin and phagocytic activity of neutrophils after -20°C storage for 7 days. CONCLUSIONS: The addition to glycerol solution (3.5%) of pectic polysaccharide АА3 (0.1%) may facilitate the formation of a three-dimensional network of intermolecular hydrogen bonds between the functional groups of pectin (mainly carboxyl) and hydroxyl groups of polyhydric alcohol. Better linkage of cellular water molecules in the biological specimen may improve cryoprotection.

Application of Pectin From Rauvolfia serpentina (L.) Benth to the Cryopreservation of Human Leucocyte Cell Suspensions.

　　BACKGROUND: Due to their valuable medicinal properties and high physiological activity, plant polysaccharides are currently being extensively studied. OBJECTIVE: The present study aims to investigate rauwolfian (pectin for Rauvolfia serpentina) supplementation on human leukocytes cryopreservation. We determined the сharacteristics of leukocytes undergoing freezing with pectin at different temperatures. METHODS: Donor leukocytes were frozen under the protection of comprehensive cryoprotectant solution and stored in electrical freezers (-20C, -40C, -80C). RESULT: A regular decrease of all values starting from a higher temperature (-20С) through to the lower temperature (-80С) was identified. The study showed that pectin rauwolfian stimulated both the oxygen-independent and the oxygen-dependent killer response. We also found that the oxygen-dependent neutrophil killer effect was reduced as the storage temperature was lowered. It was determined that the LPO levels in the cells with added pectin-containing solutions remained the same before freezing, while their antioxidant activity positively increased, which is beneficial for neutrophils for their further freezing to -20C, -40C and -80C. CONCLUSIONS: The results of the study make it possible to assume that rauwolfian, a pectin extracted from Rauvolfia serpentina, has an exocellular protectant effect as part of cryopreservative solution on human white blood cells stored at different low temperatures. The versatility of the substance is probably due to the degree of the macromolecule branching, in particular, the structure of carbohydrate side chains, which contain a large number of hydroxyl groups.

The Ability of Pectins to Modulate the Action of Glycerol In the Freezing of Nucleated Cells.

BACKGROUND: Pectins have a large number of active -OH and -COOH groups (3), suggesting the presence of this group of substances specific cryoprotective effect. OBJECTIVE: This research is aimed at studying the ability of pectins (zosteran, apple pectin АU-701, E-440) to change the freezing temperature of glycerol, which can increase the effect in the cryopreservation of nuclear cells. METHODS: Using the cryoscopic method we studied the ability of pectins (zosteran, apple pectin AU-701, E-440) to change the freezing temperature of glycerol. Heparinized venous blood was frozen under the protection of a complex cryoprotectant and stored in an electric freezer at -80 degree C for 1 day. RESULT: The research shows that pectins in a concentration of 0.6 - 1.0% increase in varying degrees the osmolality of the glycerol solution, which helps to low its freezing temperature. According to the viability of leukocytes which had been frozen to -80 degree C in glycerol habitat and one of the pectins, we found out that all pectins in concentration (0.6%) are capable to increase the cryoprotective effect of glycerol. CONCLUSIONS: The obtained data on the preservation of leukocyte membranes and the phagocytic activity of neutrophils after freezing) in glycerol habitat and glycerol with pectin confirm the authors' supposition that decrease in freezing temperature of a solution of glycerol in the presence of pectin helps to reduce the risk of cell damage during freezing. Apple pectin AU-701 is able to strengthen the cryoprotective effect of glycerol in a greater grade. It is possible due to the large number of hydroxyl and carboxyl groups (the galacturonic acid content is 95%) and the presence of methyl groups in the pectin molecule (the degree of methyl etherification is 38-40%). These groups are the most often found in the molecules of effective cryoprotectants.

Endogenous Sensitizer of Beta-Adrenergic Receptors (ESBAR) as a Component of Humoral Links Element of Autonomic Nervous System and Its Analogs (Review).

Kirov State Medical Academy, Kirov The results of the 20-years studies of the presence in blood serum and other body fluids of endogenous modulators of adrenergic and M-cholinergic impact a A COMPONENT of humoral element of autonomic nervous system. The article is devoted to the endogenous sensitizer of beta-adrenergic receptor (ESBAR) - water-soluble low molecular weight substances, analogues of which are histidine, tryptophan, tyrosine, mildronat and preduktal. It is shown, that separate dilutions of human serum and animal (as a source of ESBAR) and ESBAR - analogues ways to enhance the effectiveness of activation of beta-adrenoceptors (AR) of smooth muscle (uterus, coronary and renal arteries, trachea, stomach), myocardium and erythrocytes and platelets (respectively influenced of histidine and tryptophan). It is reported? that content of ESBAR in human serum (according to the titers of its dilution) depends on the sex and the presence of somatic diseases, and at women are also on the stage of reproduction and obstetric complications It is discussed hossible mechanisms of ESBAR action, its physiological role, including as a component of beta-adrenoreceptor myometrium inhibitory mechanism, as well as the prospect of the use of analogues ESBAR, including for the prevention of preterm labor, and for the treatment of bronchial asthma, coronary heart disease, hypertension and heart failure.

Effect of In Vitro Cold Exposure on Phagocytic Activity of Human Peripheral Blood Neutrophils.

Experiments on peripheral blood leukocytes from healthy donors using the biochemiluminescent method demonstrated the possibility of in vitro modulating phagocytic activity of neutrophils by cold exposure. Cold exposure at 2°C for 30 min increased phagocytic activity of cells, while slow cooling to -2°C reduced it.

[Effect of inert gas xenon on the functional state of nucleated cells of peripheral blood during freezing].

A new method of preservation of nucleated cells in the electric refrigerator with xenon. After slow freezing and storage is even one day at -80 °C persists for more than 60% leukocytes. Cell membranes are resistant to the vital dye. In 85% of granulocytes stored baseline lysosomal-cationic protein, reduced lipid peroxidation and antioxidant activity. Cryopreservation of biological objects in inert gases is a promising direction in the practice of medicine and can be an alternative to the traditional method using liquid nitrogen.

The use of inert gas xenon for cryopreservation of leukocytes.

We studied the possibility of cryopreservation of human blood nuclear cells under protection with inert gas xenon. A method for inducing clathrate anabiosis of leukocytes was developed that preserved the cells for practical use in biology and medicine.

Influence of pectins on NADPH oxidase and phagocytic activity of neutrophils during cryopreservation.

NADPH oxidase activation was studied by detecting the reactive oxygen species (ROS) and the dynamics of neutrophil phagocytic activity in blood before freezing and one day after exposure to -20 degrees C in the presence of pectic polysaccharides. Pectins (excluding lemnan) were found to increase the phagocytic activity of neutrophils, promote the formation of ROS in these cells and enhance NADPH oxidase activity in the following order: bergenan, comaruman, lemnan, apiuman, and potamogetonan. Cryoprotective action of lemnan and comaruman was proposed to be related to their unique chemical structures.

[Preservation of leukocytes at moderately low temperature].

It was shown that the use of little toxic cold-protective containing the glycerol protector endocellular action, HES--protector exocellular action, and "restored" component of the succinate 3-hydroxy-6-methyl-2- ethylpyridine preserves nuclear blood cells in a viable condition at -40 degrees C.

[Leucocytes conservation in the near-zero temperature].

The intensive metabolism and fast exhaustion of an energy potential of nuclear blood cells at positive temperatures essentially reduce terms of their storage in a viable condition. However for the clinical purposes given thensfusion environment is the extremely necessary. The popular method of preservation of cells at ultralow temperature (-196 degrees C) is limited in application since assumes use of the liquid nitrogen, the special equipment, trained engineering personnel. The work is devoted to development effective and simple in execution of a method of preservation of leukocytes in conditions of temperatures about zero (+2 degrees--0 degrees C) with use of a household elecrorefrigerator and new cryopreservation a solution.