Novel association between sperm deformity index and oxidative stress-induced DNA damage in infertile male patients.
OBJECTIVE
To investigate the impact of abnormal sperm morphology using the sperm deformity index (SDI) on reactive oxygen species (ROS) production and its correlation with sperm DNA damage.


METHODS
Semen samples were collected from men undergoing infertility screening (n = 7) and healthy donors (n = 6). Mature spermatozoa were isolated and incubated with 5 mmol/L beta-nicotinamide adenine dinucleotide phosphate (NADPH) for up to 24 h to induce ROS. Sperm morphology was evaluated using strict Tygerberg's criteria and the SDI. ROS levels and DNA damage were assessed using chemiluminescence and terminal deoxynucleotidyl transferase-mediated fluorescein-dUTP nick end labeling (TUNEL) assays, respectively.


RESULTS
SDI values (median [interquartiles]) were higher in patients than donors (2 [1.8, 2.1] vs. 1.53 [1.52, 1.58], P = 0.008). Aliquots treated with NADPH showed higher ROS levels (1.22 [0.30, 1.87] vs. 0.39 [0.10, 0.57], P = 0.03) and higher incidence of DNA damage than those not treated (10 [4.69, 24.85] vs. 3.85 [2.58, 5.10], P = 0.008). Higher DNA damage was also seen following 24 h of incubation in patients compared to donors. SDI correlated with the percentage increase in sperm DNA damage following incubation for 24 h in samples treated with NADPH (r = 0.7, P = 0.008) and controls (r = 0.58, P = 0.04).


CONCLUSIONS
SDI may be a useful tool in identifying potential infertile males with abnormal prevalence of oxidative stress (OS)-induced DNA damage. NADPH plays a role in ROS-mediated sperm DNA damage, which appears to be more evident in infertile patients with semen samples containing a high incidence of morphologically abnormal spermatozoa.
Said
Tamer M
TM
Center for Advanced Research in Human Reproduction, Infertility and Sexual Function, Glickman Urological Institute, Department of Obstetrics-Gynecology, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Desk A19.1, Cleveland, OH 44195, USA.
Aziz
Nabil
N
Sharma
Rakesh K
RK
Lewis-Jones
Iwan
I
Thomas
Anthony J
AJ
Agarwal
Ashok
A
D004249:DNA Damage; D006801:Humans; D007248:Infertility, Male / Q000235:genetics / Q000473:pathology*; D008297:Male; D018384:Oxidative Stress; D017382:Reactive Oxygen Species; D013094:Spermatozoa / Q000002:abnormalities*
D017382:Reactive Oxygen Species