the effect of antioxidant compounds on sperm storage

During the stages of freezing, storage, and thawing of sperm, there may be decreases in viability and motility, dna damage, and morphological abnormalities 1. these damages are caused by the plasma membrane being more sensitive to cryopreservation due to low cholesterol and high unsaturated fatty acids 2,3. to prevent this problem, antioxidants are added to the extender. these substances play an important role in reducing the stress that occurs during freezing and minimizing the damage caused by reactive oxygen species (ros) 4. most of the oxygen used by spermatozoa to produce atp in mitochondria is converted into water, while 1-2% is undesirably converted into superoxide anion (o2¯) and converted into hydrogen peroxide (h2o2) by the superoxide dismutase (sod) enzyme found in the cell s cytoplasm. if there are no antioxidants to reduce h₂o₂ to water, it will rapidly convert to hydroxyl (oh¯) radicals via iron ions in the environment. although the h₂o₂ metabolite is less active, it can damage the entire cell because it can pass through biological membranes and triggers apoptosis in spermatozoa 5,6. antioxidant substances added to sperm diluents donate electrons to stabilize ros, thereby reducing the oxidation of fatty acids in the spermatozoa membrane and causing less dna damage 7. it has been reported that antioxidant compounds added to the semen of various species improve post-thaw sperm quality following cryopreservation 8,9. hesperidin, curcumin, sulforaphane, epigallocatechin gallate, luteolin, and syringic acid have been added to sperm diluents of various types, yielding successful results. in conclusion, exogenous antioxidant supplements added to sperm diluents increase sperm quality by inhibiting oxidative stress and apoptosis at effective doses after cryopreservation.