sperm is particularly susceptible to reactive oxygen species (ros) during critical phases of spermiogenesis. however, the level of seminal ros is restricted by seminal antioxidants which have beneficial effects on sperm parameters and developmental potentials. mitochondria and sperm plasma membrane are two major sites of ros generation in sperm cells. besides, leukocytes including polymer phonu...

infertility is one of the most stressful conditions amongst married couples. male factor infertility is implicated in almost half of these cases. recent advances in the field of reproductive medicine have focused the attention of many researchers to consider reactive oxygen species (ros) as one of the mediators of infertility causing sperm dysfunction. although, ros is involved in many physiolo...

background: excess reactive oxygen species (ros) in the semen is believed to affect fertility in men. morphologically abnormal sperms and their relation to seminal oxidative stress in infertile and subfertile men are not clear. objective: to correlate various sperm morphological defects with seminal oxidative stress in infertile and subfertile men. materials and methods: the study included 25 p...

drought stress is one of the serious problems that restricted agronomic plant production worldwide. inmolecular level, the harmful effect of drought stress is mostly caused by producing of large amount ofreactive oxygen species (ros). catalase and metallothionein genes have a crucial role to mope the hydrogenperoxide (h2o2) resulting reducing oxidative damage. in this research the gene expressi...

in assisted reproduction techniques (art) settings, reactive oxygen species (ros) can be produced from endogenous and exogenous sources during in vitro manipulation. endogenous sources of ros include gametes and embryo, whereas exogenous sources are oxygen tension, light exposure, culture media, and the nature of some protocols, such as centrifugation or cryopreservation. elevated ros productio...

metals can cause oxidative stress by increasing the formation of reactive oxygen species (ros), which make antioxidants incapable of defiance against growing amounts of free radicals. metal toxicity is related to their oxidative state and reactivity with other compounds. however, several reports about metals have been published in the recent years. mitochondria, as a site of cellular oxygen con...

In the present study, different oxygen levels were examined in two weight groups of great sturgeon Huso huso including small size (with initial weight 280.9 ± 49.2 g) and large size (with initial weight 1217.9 ± 138.1 g). The fish were kept in hypoxia (2-3 mg/l), normoxia (5-6 mg/l) and hyperoxia (9-10 mg/l) conditions for 8 weeks and then were individually placed in the tanks with oxygen lev...

objective(s):many studies have reported that tea consumption decreases cardiovascular risk, but the mechanisms remain unclear. green tea is known to have potent antioxidant and free radical scavengingactivities. this study aimed to investigate whether green tea extract (gte) can protect endothelial progenitors cells (epcs) against oxidative stress through antioxidant mechanisms. materials and m...

objective(s): exposing to stress may be associated with increased production of reactive oxygen species (ros). therefore, high level of oxidative stress may eventually give rise to accumulation of oxidative damage and development of numerous neurodegenerative diseases. it has been presented that brain-derived neurotrophic factor (bdnf) supports neurons against various neurodegenerative conditio...

background: this case-control study was designed with the aim of evaluating the role of sperm, oxidative stress and dna damage in idiopathic recurrent pregnancy loss (irpl). this pilot study is the first study done on the indian population which reports the association between dfi, tac and ros in couples experiencing irsa. methods: twenty infertile men with a history of irpl and 20 fertile cont...