INVESTIGATING OXIDATIVE STRESS AND ANTIOXIDANTS IN MALE INFERTILITY

ABSTRACT

Male factor infertility has assumed an important public health challenge. Apart from abnormal sperm indices, oxidative DNA damage has been implicated in its aetiology. This study determines the levels of 8-hydroxy-2′-deoxyguanosine (8-OHdG) and some markers of oxidative stress in seminal fluids of males investigated for infertility and men of proven fertility in Benin City, Nigeria. Semen samples were produced by masturbation or coitus interruptus after at least three days of sexual abstinence. Semen analysis was done by microscopic technique according to World Health Organization. The samples were then centrifuged and seminal fluid plasma was then separated and stored at -20⁰ C prior to assay for 8-OHdG and antioxidants. Based on the sperm concentration/count, the overall samples were grouped into the following categories: Normospermia (n=20), mild Oligozoospermia (n=10), moderate Oligozoospermia (n=10), severe Oligozoospermia (n=10) and Azoospermia group (n=20) as well as Control (n=30).The seminal fluid 8-OHdG was measured by Enzyme linked immunosorbent assay (ELISA) technique; while total antioxidant status (TAS), superoxide dismutase (SOD) and malondialdehyde (MDA) were assayed by spectrophotometric methods using commercially available reagents kits. Seminal plasma level of 8-OHdG and MDA were significantly higher (p<0.001) in infertile subjects than controls. The mean levels of 8-OHdG and MDA in infertile subjects increased from normospermia to oligozoospermia and azoospermic subjects. Conversely, the mean levels of TAS and SOD were significantly lower (p<0.001) in infertile male than fertile control male subjects with levels decreasing from normospermic to oligozoospermic and azoospermic infertile male subjects. Seminal fluid 8-OHdG correlated negatively with TAS, SOD and positively with MDA in the study participants.The assessment of sperm DNA damage in addition to routine seminal fluid analysis may play an important role in specific diagnosis and management of male infertility.