Blood/seminal serotonin levels in infertile men with varicocele

Significant alterations of 6-keto prostaglandin F1a and NO levels in spermatic vein plexus patients with varicocele

To investigate the level variation of correlative factors between the spermatic vein plexus and peripheral blood in patients with varicocele, a total of 22 patients diagnosed with varicocele were enrolled in the study. All patients were performed a testicular artery-sparing microsurgical varicocelectomy. During the operation, a blood sample from the left spermatic vein plexus and a peripheral blood sample were collected. A radioimmunoassay was used to determine the 6-keto prostaglandin F1a (6-keto-PGF1a ). A colorimetric method was performed to determine the NO. The enzyme immunoassay method was used to determine the creatinine, urea nitrogen, adrenaline, noradrenaline, dopamine and 5-HT. The mean age of all patients was 29.3 ± 7.8 years. Compared with the level of 6-keto-PGF1a and NO in the peripheral blood, 6-keto-PGF1a and NO were significantly increased in left spermatic vein plexus (347.3 (230.8-415.1) versus 99.7 (80.4-119.9) pg/ml and 192.3 ± 178.5 versus 107.1 ± 73.6 μmol/L, p < .05). There were no differences in the level of creatinine, urea nitrogen, adrenaline, noradrenaline, dopamine and 5-HT between the peripheral blood and left spermatic vein plexus (p > .05). The 6-keto-PGF1a and NO concentrations in left spermatic vein plexus were significantly higher than that in peripheral blood patients with varicocele.

Large-scale evaluation of SLC18A2 in prostate cancer reveals diagnostic and prognostic biomarker potential at three molecular levels

Limitations of current diagnostic and prognostic tools for prostate cancer (PC) have led to over-diagnosis and over-treatment. Here, we investigate the biomarker potential of the SLC18A2 (VMAT2) gene for PC at three molecular levels. Thus, SLC18A2 promoter methylation was analyzed in 767 malignant and 78 benign radical prostatectomy (RP) samples using methylation-specific qPCR and Illumina 450K methylation microarray data. SLC18A2 transcript levels were assessed in 412 malignant and 45 benign RP samples using RNAseq data. SLC18A2 protein was evaluated by immunohistochemistry in 502 malignant and 305 benign RP samples. Cancer-specificity of molecular changes was tested using Mann-Whitney U tests and/or receiver operating characteristic (ROC) analyses. Log rank, uni- and multivariate Cox regression tests were used for survival analyses. We found that SLC18A2 promoter hypermethylation was highly cancer-specific (area under the curve (AUC): 0.923-0.976) and associated with biochemical recurrence (BCR) after RP in univariate analyses. SLC18A2 transcript levels were reduced in PC and had independent prognostic value for BCR after RP (multivariate HR 0.13, P < 0.05). Likewise, SLC18A2 protein was down-regulated in PC (AUC 0.898) and had independent prognostic value for BCR (multivariate HR 0.51, P < 0.05). Reduced SLC18A2 protein expression was also associated with poor overall survival in univariate analysis (HR 0.29, P < 0.05). Our results highlight SLC18A2 as a new promising methylation marker candidate for PC diagnosis. Furthermore, SLC18A2 expression (RNA and protein) showed promising prognostic potential beyond routine clinicopathological variables. Thus, novel SLC18A2-based molecular tests could have useful future applications for PC detection and identification of high-risk patients.

The correlation between urinary 5-hydroxyindoleacetic acid and sperm quality in infertile men and rotating shift workers

BACKGROUND

Serotonin is a neurotransmitter that modulates a wide range of neuroendocrine functions. However, excessive circulating serotonin levels may induce harmful effects in the male reproductive system. The objective of this study was to evaluate whether the levels of urinary 5-hydroxyindoleacetic acid (5-HIIA), a major serotonin metabolite, correlate with different classical seminal parameters.

METHODS

Human ejaculates were obtained from 40 men attending infertility counselling and rotating shift workers by masturbation after 4-5 days of abstinence. Urinary 5- HIIA concentration was quantified by using a commercial ELISA kit. Forward motility was assessed by a computer-aided semen analysis (CASA) system. Sperm concentration was determined using the haemocytometer method. Sperm morphology was evaluated after Diff-Quik staining, while sperm vitality was estimated after Eosin-Nigrosin vital staining.

RESULTS

Our results show that urinary 5-HIIA levels obtained from a set of 20 volunteers negatively correlated with sperm concentration, forward motility, morphology normal range and sperm vitality. On the other hand, we checked the relationship between male infertility and urinary 5-HIIA levels in 20 night shift workers. Thus, urinary 5-HIIA levels obtained from 10 recently-proven fathers were significantly lower than those found in 10 infertile males. Additionally, samples from recent fathers exhibited higher sperm concentration, as well as better forward motility and normal morphology rate.

CONCLUSIONS

In the light of our findings, we concluded that high serotonin levels, indirectly measured as urinary 5-HIIA levels, appear to play a role as an infertility determinant in male subjects.