Relationship of MTHFR gene polymorphisms with infertility / 中华男科学杂志

The folate metabolic pathway plays important roles in cellular physiology by participating in nucleotide synthesis, DNA repair and methylation, and maintenance and stability of the genome. Methylenetetrahydrofolate reductase (MTHFR) is a key regulatory enzyme involved in folate metabolism. Polymorphisms of MTHFR may change the level of homocysteine and affect DNA synthesis and methylation, leading to an increased oxidative stress and disturbed methylation reactions and consequently affecting reproductive function. This article presents an overview on MTHFR gene polymorphisms, proposing that multicentered, large-sample and long-term prospective studies are needed to reveal the relationship between MTHFR gene polymorphisms and infertility.

Protective effect of lycopene on human spermatozoa during cryopreservation and its mechanism / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the protective effect of lycopene against cryopreservation injury of post-thawing human sperm and its mechanism.</p><p><b>METHODS</b>Semen samples were collected from 25 volunteers, each sample equally divided into four parts to be cryopreserved with cryoprotectant only (Ly0 control) or cryoprotectant + lycopene at the concentrations of 2 (Ly2), 5 (Ly5), and 10 µmol/L (Ly10), respectively. Before and after thawing, the semen samples were subjected to computer-assisted semen analysis ( CASA) for sperm kinematics, flow cytometry for sperm apoptosis, thiobarbituric acid assay for malondialdehyde (MDA) concentration, and JC-1 fluorescent staining for the sperm mitochondrial membrane potential (MMP).</p><p><b>RESULTS</b>After cryopreservation, sperm motility was markedly decreased in all the groups (P < 0.01). The rate of sperm apoptosis was significantly lower in the Ly5 group than in the Ly0 control ([25.68 ± 4.36]% vs [33.26 ± 4.78]%, P < 0.05), while sperm MMP remarkably higher in the former than in the latter ([66.18 ± 14.23]% vs [55.24 ± 12.31]%, P < 0.05). The Ly2, Ly5 and Ly10 groups showed no statistically significance differences in the MDA level from the Ly0 control (P > 0.05).</p><p><b>CONCLUSION</b>Addition of lycopene at a proper concentration to cryoprotectant may reduce oxidative damage to sperm mitochondria in the freezing-thawing process, attenuate oxidative stress injury induced by reactive oxygen species to sperm plasma membrane, and improve the anti-apoptosis ability of sperm.</p>

Expressions of differential proteins in the expressed prostatic secretion of patients with III A chronic prostatitis / 中华男科学杂志

<p><b>OBJECTIVE</b>To study the expressions of differential proteins in the expressed prostatic secretion (EPS) of patients with III A chronic prostatitis and healthy men.</p><p><b>METHODS</b>We collected EPS samples from 35 patients with III A chronic prostatitis and 18 age-matched healthy men, and detected the differentially expressed proteins in EPS by MALDI-TOF/MS. Based on the data obtained, we conducted a statistical analysis on the mass-to-charge (m/z) ratios of different proteins and a retrieval analysis on the relevant proteins using the protein database.</p><p><b>RESULTS</b>In the comparative studies of the III A chronic prostatitis patients and healthy men, 5 proteins were detected as at least 2-fold differentially expressed, which were probably brevinin-2Eg, big endothelin-1, alpha-defensin 15, beta-defensin 134 and prostatic steroid-binding protein C2. The m/z ratios were significantly up-regulated in 3 372, 3 487, 425 and 5 325 Da proteins (P < 0.01) and down-regulated in 10631Da (P < 0.01).</p><p><b>CONCLUSION</b>Proteins are differentially expressed in the EPS of III A chronic prostatitis patients and healthy men, and these proteins may be significantly correlated with the development and progression of III A chronic prostatitis.</p>