Document Type : Original Article
Department of Animal Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran
R&D Department, Parthenogen, Piazza Indipendenza 11, Lugano 6900, Switzerland
Department of Cell and Molecular Biology, Cell Sciences Research Center, Royan Institute for Animal Biotechnology, ACECR, Isfahan, Iran
Objective: Cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE) are two important enzymes involved in
One-Carbon metabolism. These enzymes play important roles in modulating oxidative stress and inflammation in male
factor infertility through participating in the synthesis of glutathione (GSH) antioxidants in the trans-sulfuration pathway.
Besides, the direct release of hydrogen sulfide (H2S) has anti-inflammatory and antioxidant effects. Therefore, the
expression of CBS and CSE genes at mRNA levels in infertile and varicocele men was evaluated and compared to the
healthy counterparts to clarify their possible role in the pathology of male infertility.
Materials and Methods: In this case-control study, semen parameter assessment (concentration, morphology, and motility of sperms) was performed on 28 men with varicocele, 43 infertile men with abnormal sperm parameters, and 19 fertile men. RNA was extracted from sperm samples followed by cDNA synthesis and real-time polymerase chain reaction (PCR) using CBS, CSE, and GAPDH primers.
Results: Sperm concentration and motility in infertile and varicocele groups were significantly lower (P=0.001), while
spermatoza normal morphology was higher than fertile group (P=0.05). The expression levels of both CBS and CSE
genes in infertile (P=0.04 and P=0.037 respectively) and varicocele (P=0.01 and P=0.046 respectively) groups were
significantly lower than fertile group. Additionally, CBS gene expression indicated a positive correlation with expression
of CSE gene (r=0.296, P=0.025) and sperm parameters.
Conclusion: In light of our findings, there is a valid rationale to consider the primary role of CBS and CSE enzymes
impairment in male factor infertility which specifically may point to a deficit in the release of essential antioxidants
including the H2S as a molecular basis of infertility and warrants further investigation.