Evaluation of Methylenetetrahydrofolate Reductase and S-adenosyl-methionine Level in Male Infertility: A Case-control Study

Background: Methylenetetrahydrofolate reductase enzyme (MTHFR) plays a key role in regulating folate balance, converting homocysteine to methionine, and producing s-adenosylmethionine (SAM) that plays a role in the methylation process. Objective: This study aimed to determine MTHFR activity and SAM level in men with normozoospermia and oligozoospermia. Materials and Methods: 30 oligozoospermic and 30 normozoospermic men as controls were enrolled in this case-control study. Semen analysis was conducted according to the world health organization criteria. All semen samples were collected after 3-5 days of sexual abstinence. The sperms were evaluated by sperm test video software. All subjects SAM level was measured by enzyme-linked immunosorbent assay kit, and MTHFR were measured manually. Results: 2 groups had a significant difference in sperm morphology (p = 0.02), concentration (p = 0.02) and motility (p = 0.03). The MTHFR activity in normozoospermic and oligozoospermic groups had significantly differences (p = 0.01). The level of SAM in the semen of oligozoospermic men was statistically lower than normozoospermic men (p = 0.03). Also, there was a positive association between MTHFR enzyme activity and SAM level in the normozoospermia group (p = 0.02, β = 0.67) and oligozoospermia group (p = 0.03, β = 0.54). Conclusion: MTHFR activity and SAM concentration were statistically lower in oligozoospermia men. It seems they can affect sperm concentration, morphology, and motility. Key words: Methylenetetrahydrofolate reductase, s-adenosylmethionine, Normozoospermia, Oligozoospermia, Folic acid