IN VITRO EFFECTS OF ISOQUERCITRIN ON SELECTED VITALITY MARKERS OF BOVINE SPERMATOZOA

Abstract

The aim of this study was to evaluate the dose- and time-dependent in vitroeffects of isoquercitrin (ISO), a natural flavonoid with numerous biological properties on bovine spermatozoa during three different time periods (0 h, 2 h, 24 h). Bovine semen samples were diluted and cultivated in physiological saline solution containing 0.5% DMSO together with 200, 100, 50, 10, 5 and 1 μmol/L ISO. Spermatozoa motility was measured using the HTM IVOS CASA (Computer Assisted Semen Analyzer) system. The viability of spermatozoa was assessed by the metabolic (MTT) assay, production of superoxide radicals was quantified using the nitroblue tetrazolium (NBT) test, and chemiluminescence was used to evaluate the generation of reactive oxygen species (ROS). The results of the movement activity showed a significant increase in the motility during long term cultivation in case of concentrationsranging between 5 and 50 μmol/L ISO (P<0.05; 24 h). At the same time, supplementation of several concentrations of ISO led to a significant preservation of the cell viability (P<0.05 in the case of 50 μmol/L, P<0.01 with respect to 1 and 5 μmol/L, and P<0.001 in relation to 10 μmol/L; 24 h). ISO addition at 10 and 50 μmol/L also provided a significantly higher protection against superoxide (P<0.05) and ROS (P<0.001) overgeneration after a 24 h cultivation. We may suggest that supplementation of ISO to bovine spermatozoa, particularly at concentrations ranging between 10 and 50 μmol/L, may offer protection to the motility, viability and oxidative status of the sperm cells, particularly notable at 24 h.