title: Effect of freezing-thawing process and quercetin on human sperm survival and DNA integrity.
abstract: We aimed in the first part of our work to study the effect of cryopreservation on the human sperm DNA integrity and the activation of caspase 3, the main apoptosis indicator. In the second part, we were interested in testing the effect of quercetin, as an antioxidant, in preventing sperm damage during the freeze-thawing process. Seventeen semen samples were obtained from 17 men recruited for infertility investigations. Liquefied sperm was cryopreserved using spermfreeze®. Nine of the used samples were divided into two aliquots; the first one was cryopreserved with spermfreeze only (control) and the second one was cryopreserved with spermfreeze supplemented with quercetin to a final concentration of 50 μM. Sperm motility and viability were assessed according to WHO criteria. We used TUNEL assay and the Oxy DNA assay to assess sperm DNA integrity. Activated caspase 3 levels were measured in spermatozoa using fluorescein-labeled inhibitor of caspase (FLICA). Cryopreservation led to a significant increase in sperm DNA fragmentation, DNA oxidation and caspase 3 activation (p<0.01). Supplementation of the cryopreservation medium with quercetrin induced a significant improvement in post thaw sperm parameters, compared to those of control, regarding sperm motility (p=0.007), viability (p=0.008) and DNA integrity (p=0.02); however, it had no effect on caspase 3 activation (p=0.3). We conclude that oxidative stress plays a major role in inducing sperm cryodamage but implication of apoptosis in this impairment requires further investigations. Quercetin could have protective effect during cryopreservation but further research is needed to confirm this effect.
authors.affiliation: Laboratory of Human Molecular Genetics, Sfax Faculty of Medicine, Magida Boulila Street, 3028 Sfax, Tunisia. nacira.zribi@gmail.com
authors.forename: Nassira
authors.initials: N
authors.lastname: Zribi
authors.forename: Nozha Feki
authors.initials: NF
authors.lastname: Chakroun
authors.forename: Fatma
authors.initials: F
authors.lastname: Ben Abdallah
authors.forename: Henda
authors.initials: H
authors.lastname: Elleuch
authors.forename: Afifa
authors.initials: A
authors.lastname: Sellami
authors.forename: Jalel
authors.initials: J
authors.lastname: Gargouri
authors.forename: Tarek
authors.initials: T
authors.lastname: Rebai
authors.forename: Faiza
authors.initials: F
authors.lastname: Fakhfakh
authors.forename: Leila Ammar
authors.initials: LA
authors.lastname: Keskes
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D053148:Caspase 3 / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D015925:Cryopreservation / Q000379:methods*; D004247:DNA / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D006801:Humans; D020287:In Situ Nick-End Labeling; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D011794:Quercetin / Q000494:pharmacology*; D012662:Semen Preservation / Q000379:methods*; D013094:Spermatozoa / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism
chemical_list: D000975:Antioxidants; D004247:DNA; D011794:Quercetin; D053148:Caspase 3