Use of biological and synthetic polymers for human spermatozoa cryopreservation.

BACKGROUND: Spermatozoa cryopreservation is an integral part of the assisted reproductive technologies for treatment of infertility. It is also used to preserve the reproductive potential of men. However, using a standard freezing method with glycerol leads to a decrease in morphological and functional characteristics of spermatozoa in the case of oligoasthenoteratozoospermia (OAT). Therefore, it is relevant to develop effective methods of cryopreservation for such sperm. The use of various biopolymers can stabilize the membrane and bind excess water, which forms ice crystals in the medium that causes cell damage when temperature decreases. OBJECTIVE: To study the effectiveness of using cryoprotectant mixtures based on biological and synthetic polymers [serum albumin, polyvinylpyrrolidone (PVP) and insulin] for the cryopreservation of human spermatozoa with OAT. MATERIALS AND METHODS: Human spermatozoa with OAT were cryopreserved using different cryoprotectant media containing 10 % glycerol or 10 % PVP, 20 % albumin and 1 µg per mL human insulin. The viability, motility and mitochondrial membrane potential of spermatozoa were assessed after rewarming. RESULTS: A cryoprotectant solution containing 10 % PVP, 20 % human serum albumin and 1 ug per mL insulin enabled a similar level (%) of viable gametes compared with the standard method using glycerol, while the number of motile cells was significantly lower (p < 0.008). The membrane mitochondrial potential did not differ significantly from fresh sperm. CONCLUSION: The data obtained in this study show the effectiveness of a biopolymer mixture containing PVP, serum albumin and insulin for the cryopreservation of human OAT spermatozoa. doi.org/10.54680/fr22410110712.

Adhesion, growth, and proliferation of endothelial cells on biopolymer extracellular film matrices.

We analyzed the influence of initial properties of biopolymer fi lm extracellular matrices made of chitosan on adhesion of swine embryonic kidney epithelium-like cells, their morphology, growth, and proliferation. It was found that adhesion index of cells on the studied matrices was similar, but cell morphology had significant qualitative differences. Round non-flattened cells were described in endothelial cell cultures on chitosan-based matrices. Local variations in charge density on matrices induced by the presence of chitin nanofibers led to the appearance of flattened spindle-shaped and non-flattened sphericalal cells. Long-term culturing on biopolymer extracellular fi lm matrices was associated by the formation of spatial conglomerates of sphericalal cells.