Parameters of spontaneous and benzene-induced cell death of spermatozoa under in vitro conditions in male employees of an oil production enterprise with impaired fertility

Abstract

Introduction. Every year there is a steady increase in the frequency of male infertility both in Russia and in other countries of the world with the concomitant low efficiency of recognizing the causes of its idiopathic forms. The explanation for the increase in infertility are: harmful production factors, including chemical ones, progressive deterioration of the quality of the urban environment, which has a significant impact on the reproductive health of the urbanized population, recurring economic crises that negatively affect the human psyche, mass consumption of substandard products and medicines. These factors, primarily chemical production, negatively affect the reproductive system, including the differentiation of male germ cells, as a cause of fertility disorders. The aim of the study to consider in vitro spontaneous and benzene-induced features of sperm apoptosis in male oil industry workers with impaired fertility. Materials and methods. We have conducted an experimental study of biological material (ejaculate) in 50 men with reproductive disorders (26-49 years old), employees of an oil production enterprise. To conduct the experiment in vitro, the researchers used seminal fluid samples. A benzene solution at a concentration of 0.001 micrograms/ml was used as an in vitro induction factor (selected experimentally). We divided the analyzed samples into 2 equal parts to study the spontaneous and benzene-induced expression of apoptosis markers (CD25+, CD95+, bax, p53, Annexin V-FITC and Propidium Iodide, Caspasa-3), which the researchers determined by flow cytometry. Results. There were no significant deviations of intracellular markers of sperm apoptosis (bax, p53, Annexin V-FITC+7AAD+, Annexin V-FITC+7AAD-, Caspasa-3), however, experts observed differences in the expression of CD95+ and CD25+ membrane proteins by 20% and 10% compared to the spontaneous level, which is associated with the acceleration of the events of programmed sperm death (p<0.05). Conclusion. The results obtained in an in vitro experiment on modeling the apoptosis program by induction with hapten (benzene) showed that violations of sperm cell death are associated with overexpression of the key receptor for triggering apoptosis CD95, as well as a marker of early activation of CD25 cells, which reflects benzene modification of the cell death scenario along the path of its excessive stimulation.