Efeito toxicológico de nanocápsulas de núcleo lipídico revestidas de quitosana sobre espermatozoides bovinos

Abstract

Nanobiotechnology is a rising area, with the continual advent of new systems to improve drug efficiency and therapies. Among the recently nanosystems developed, the lipid core nanocapsules stand out for the ability to carry different types of molecules in their nucleus or adhered to their surface. For nanosystems to be commercially employed, their animal and environmental and animal harmlessness must be proven. To address this emerging need, toxicology seeks the use of faster screening models, such as the use of male gametes and the evaluation of fertility parameters. The objective of this study was to evaluate the effect of two nanosystems of lipid core nanocapsules, composed of sorbitan monostearate, capric-caprylic triglycerides, polycaprolactone, lecithin and polysorbate, and the second one coated with chitosan, in bovine spermatozoa for evaluation of toxicity through sperm quality parameters. The evaluation of the profile and distribution of nanocapsule size was performed by laser diffraction and dynamic scattering of light, the zeta potential was measured by electrophoresis. In this study two nanosystems, lipid core nanocapsules (LNC) and chitosan-coated lipid core nanocapsules (LNC-CS) were tested commercial samples of five local bulls. The effect of the nanocapsules was analyzed in immediate contact (0 h) and after incubation for 1 h. Five concentrations of nanocapsules were tested: 2.5%, 5%, 10%, 20% and 40% (v / v). An additional concentration of 80% was used for the motility tests. Two control groups were used, replacing the nanocapsules with medium or water, with the same concentrations. Toxicity was assessed through changes in the sperm motility pattern by CASA, and cell cytometry by flow cytometry. There was no significant difference between the groups incubated with LNC and LNC-CS and the control groups at concentrations of less than 40%. In the 40% groups, there was decrease of motility between experimental groups and control for the DAP parameter of the CASA analysis in the two incubation periods for the two nanosystems, and in membrane integrity for both times in the group with LNC-CS. Mitochondrial activity was also reduced for LNC-CS in 0 h time. There was a reduction in the parameters of motility, DAP, DCL, DSL, VAP, VCL, VSL, STR, LIN, WOB, ALH, BCF, for 80% concentration in the groups incubated with LNC and LNC-CS. In conclusion, this study demonstrated the reduced toxicity caused only at very high concentrations, enabling the use of LNC and LNC-CS as a nanocarrier for sperm cells.