title: Effect of nerve growth factor on sperm quality in asthenozoosprmic men during cryopreservation.
abstract: BACKGROUND
  Although routinely used in assisted reproductive technology, human sperm cryopreservation is not an entirely successful procedure. This study determined the effect of nerve growth factor (NGF) supplementation of cryopreservation medium on post-thaw viability, motility, intracellular nitric oxide (NO) concentration, and DNA fragmentation of human spermatozoa in asthenozoospermic men.
  
  
  METHODS
  Semen samples were collected from 25 asthenozoosprmic men and divided into the following groups (n = 5/group): fresh semen (control); frozen-thawed semen without treatment; frozen-thawed semen with NGF treatment (0.5, 1, and 5 ng/ml). Prior to dividing the asthenozoospermic samples, 200 μl of each sample was collected for NGF content assessment by ELISA and then compared with normozoospermic semen samples (25 normozoospermic men). Sperm motility and viability were assessed according to WHO criteria. Furthermore, intracellular nitric oxide and DNA fragmentation were evaluated by Flow Cytometry.
  
  
  RESULTS
  NGF content was significantly higher in normozoospermic compared with asthenozoospermic men. Cryopreservation of asthenozoospermic semen samples significantly decreased sperm viability and motility, and increased intracellular nitric oxide concentration and DNA damage (p < 0.01). In asthenozoospermic frozen-thawed samples treated with 0.5 ng/ml exogenous NGF, we observed a significantly increased viability, motility, and decreased DNA fragmentation (p < 0.05), but intracellular nitric oxide concentration was not reduced. The other high doses (1 and 5 ng/ml) had no significant effect on the variables.
  
  
  CONCLUSIONS
  Supplementation with exogenous NGF could have partial and limited protective effect during cryopreservation of human spermatozoa but further research is needed to evaluate the possible clinical applications.
authors.affiliation: School of medicine, Shahroud University of Medical Sciences, Shahroud, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Saeednia
authors.affiliation: Department of Anatomy, School of medicine, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Shabani Nashtaei
authors.affiliation: Department of Anatomy, School of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Bahadoran
authors.affiliation: Department of Infertility, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ashraf
authors.initials: A
authors.lastname: Aleyasin
authors.affiliation: Department of Anatomy, School of medicine, Tehran University of Medical Sciences, Tehran, Iran. Famidi@sina.tums.ac.ir.
authors.forename: Fardin
authors.initials: F
authors.lastname: Amidi
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D053627:Asthenozoospermia / Q000628:therapy*; D002470:Cell Survival / Q000187:drug effects; D015925:Cryopreservation / Q000379:methods*; D053938:DNA Fragmentation; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D020932:Nerve Growth Factor / Q000494:pharmacology*; D009569:Nitric Oxide / Q000378:metabolism; D055101:Semen Analysis; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology
chemical_list: D009569:Nitric Oxide; D020932:Nerve Growth Factor
keywords: Cryopreservation; DNA fragmentation; Human spermatozoa; Nerve growth factor; Nitric oxide