Cryoprotective effect of resveratrol on DNA damage and crucial human sperm messenger RNAs, possibly through 5’ AMP-activated protein kinase activation

Background: Besides the assessment of DNA integrity, knowing the molecular health of sperm samples after the freeze–thaw process would be critical. We recently showed that the protective features of resveratrol, a polyphenol found in numerous plant species, on cryopreservation-induced oxidative stress may be mediated through activation of AMP-activated protein kinase (AMPK). Thus, this work aimed at investigating the beneficial effect of resveratrol on (i) DNA integrity and (ii) fertilizing capacity of sperm by quantifying the presence of key paternal transcripts considered as markers for male fertility (protamine 1 [PRM1] and protamine 2 [PRM2]) and pregnancy success (adducin 1 alpha [ADD1]) in cryopreserved human spermatozoa through modulation of AMPK.Methods: Spermatozoa from 22 normozoospermic men were incubated with or without AMPK activator (Resveratrol [RSV]) or inhibitor (Compound C [CC]) for 1 hour and were then cryopreserved. Untreated frozen–thawed spermatozoa served as controls.Result: The RSV-induced AMPK activation decreased the level of DNA fragmentation in comparison with the control (21.18 ± 0.92 versus 22.50 ± 0.40; P < 0.01). The relative mRNA expression levels of protamines (1 and 2) and ADD1 in RSV pretreated frozen- thawed human spermatozoa were also improved significantly compared to the control (p < 0.05). Besides, the inhibitory effect of CC on AMPK activity deteriorated the deleterious effects of cryopreservation on these parameters (p < 0.01).Conclusion: In conclusion, these results demonstrated the cryoprotective effect of the RSV-induced increase in AMPK activity on DNA integrity and key paternal transcripts of cryopreserved human spermatozoa.

Keywords:

AMP-activated protein kinase , cryopreservation , DNA damage , human sperm , qPCR , Resveratrol