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>