ESTUDO DO EFEITO DAS NANOPARTÍCULAS DE SAIS DE PRATA SOBRE PARÂMETROS REPRODUTIVOS E FUNCIONAIS ESPERMÁTICOS EM RATOS WISTAR

Abstract

Nanotechnology research and applications has had a remarkable growth over the last years. Silver nanoparticles (AgNPs) have several applications but among them emphasize its antimicrobial potential and due to the current problem of bacterial resistance, it is becoming focus of studies of new drugs that act as antimicrobials or in synergism with current antibiotics. Allied to this, are being widely explored in health care field with widespread use in many consumer products. The high level of commercialization increases the access of silver in nanoparticles shapes, tissues, cells and biological molecules within the human body, which can result in toxicity to human health in several areas including reproduction. The aim of this study is to evaluate the effect of AgNPs 60 nm and concentration of 0.02 mg/mL on reproductive parameters and functional sperm in male Wistar rats. Were used as experimental model 30 animals, divided into three groups, one control group receiving 0 mg/kg AgNPs and two test groups receiving doses of 0.015 mg/kg and 0,030 mg/kg AgNPs. The animals were observed from pre puberty to adulthood and the product has received by gavage from 23 days to 59 days age. The functional parameters evaluation of sperm included sperm assessment of plasma membrane integrity through Eosin/ Nigrosine staining, acrosomal integrity using Pope staining, mitochondrial activity evaluation via DAB and DNA evaluation of integrity by the comet assay. Reproductive parameters were evaluated in order to check possible tissue, endocrine and behavioral changes in animals and included age assessment and weight at puberty, sperm analysis count, daily sperm production per testis and epididymis transit time, check pathologies in animal’s semen, assessment orientation and sexual behavior. The prepubertal exposure showed AgNPs compromising the sperm functionality treated animals displayed by reduction in the acrosome integrity and the plasma membrane integrity and reduction in mitochondrial activity of spermatozoa, since damage to sperm DNA integrity has not been viewed. The animals showed a delay in days as well as a greater weight to reach puberty. There were no change in sperm count and daily sperm production per testis, but the sperm reserve in treated animals showed a reduction in sperm concentration and there was acceleration in sperm transit time, both in the epididymis tail. The sperm of treated animals showed pathologies and there were changes in sexual orientation, where animals showed sexual preference for males, since sexual behavior was not affected. The hormonal analysis revealed that the substance has not changed the hormones pattern. The results altogether pointed out that there was impairment of semen quality and reproductive parameters showing that the AgNPs, even at extremely low doses has extreme potential to affect male fertility.