Soluble urokinase-type plasminogen activator receptor as a putative marker of male accessory gland inflammation

Chronic Prostatitis/Chronic Pain Pelvic Syndrome and Male Infertility

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is defined as urologic pain or discomfort in the pelvic region, associated with urinary symptoms and/or sexual dysfunction, lasting for at least 3 of the previous 6 months. The rate of symptoms related to prostatitis has a mean prevalence of 8-8.2%. CP/CPPS is most frequent in men younger than 50 years, among whom it is the most common urologic diagnosis. In the last decades, many studies have been published on CP/CPPS and its association with male infertility. The pathophysiologic relation between CP/CPPS and male infertility involves several aspects, which are not well studied yet. A reduction in semen parameters has been demonstrated in patients with CP/CPPS, and several mechanisms have been proposed to represent putative pathophysiological links between CP/CPPS and infertility, including male accessory gland inflammation, metabolic syndrome, inflammatory bowel disease, HPV co-infection and autoimmunity. In light of this evidence, a multidisciplinary approach is advocated for patients with known CP/CPPS, and particular attention is needed for male patients of infertile couples in order to evaluate male accessory glands correctly. In addition, it is advisable that future studies dealing with the treatment of CP/CPPS take into consideration all the different pathophysiological aspects implicated.

Total urokinase-type plasminogen activator (uPA) levels in seminal plasma are associated with positive assisted reproductive technology outcomes

PURPOSE

The plasminogen/plasmin system is an important extracellular protease system whose function has been implicated in male reproductive function. However, its clinical relevance to fertility in human assisted reproduction technologies has not been systematically investigated. Here, we examined whether total and active populations of urokinase-type plasminogen activator (uPA) in human seminal plasma and spermatozoa are predictive of pregnancy outcome in couples undergoing insemination or intracytoplasmic sperm injection (ICSI).

METHODS

Seminal samples from 182 men, 5 donors, 21 patients attending the clinic for infertility screening, and 156 for assisted reproduction technology (ART) treatment (insemination and ICSI), were evaluated. Total uPA in seminal plasma and spermatozoa as well as active uPA in seminal plasma were measured by ELISA. Sperm quality parameters and fertility outcomes following insemination or ICSI were correlated with the uPA values.

RESULTS

Active uPA in seminal plasma was positively correlated to the volume of the ejaculate, total number of spermatozoa in the ejaculate, and total motility. However, these values were not prognostic of fertility outcomes. Total uPA in spermatozoa was inversely related to sperm concentration, total sperm in ejaculate, morphology, and total and progressive motility, and this measure was not related to fertility. Importantly, however, higher values of total uPA in seminal plasma were detected in cases that resulted in pregnancy compared to those that did not follow insemination and ICSI treatment.

CONCLUSIONS

Taken together, these findings lay the foundation for further understanding the mechanism by which total uPA in seminal plasma affects fertility and how this marker can be used as a predictor of ART outcomes.

Cervical mucus proteome in endometriosis

Background

Endometriosis is a chronic gynecological inflammatory disease characterized by the presence of functional endometrial glands and stroma outside of the uterine cavity. It affects 7–10% of women of reproductive age and up to 50% of women with infertility. The current gold standard for the diagnosis combines laparoscopic evaluation and biopsy of the visualized lesions. However, laparoscopy requires general anesthesia and developed surgical skills and it has a high procedural cost. In addition, it is associated with the risk, although rare, of potential intraoperative or postoperative complications. To date, several noninvasive biomarkers have been proposed; however, no definite diagnostic biomarker is yet available. The aim of this study was to characterize the CM proteome in patients with endometriosis using high resolution mass spectrometry—based proteomics, implemented by bioinformatic tools for quantitative analysis, in order to investigate the pathophysiological mechanisms of endometriosis.

Methods

Cervical mucus samples were collected from patients affected by endometriosis and fertile controls. An aliquot of the soluble acidic fraction of each cervical mucus sample, corresponding to 0.5 mg of total protein, was left to digest with sequencing grade modified porcine trypsin. The peptides were analyzed by LC–MS/MS on a high resolution Orbitrap Elite mass spectrometer and data were evaluated using bioinformatic tools.

Results

We aimed at the first total profiling of the cervical mucus proteome in endometriosis. From the list of identified proteins, we detected a number of differentially expressed proteins, including some functionally significant proteins. Six proteins were quantitatively increased in endometriosis, almost all being involved in the inflammatory pattern. Nine proteins were quantitatively reduced in endometriosis, including some proteins related with local innate immunity (CRISP-3 and Pglyrp1) and protection against oxidative stress (HSPB1). Fifteen proteins were not detected in endometriosis samples including certain proteins involved in antimicrobial activity (SLURP1 and KLK13) and related to seminal plasma liquefaction and male fertility (KLK13).

Conclusions

This is the first application of high resolution mass spectrometry—based proteomics aimed in detecting an array of proteins in CM to be proposed for the noninvasive diagnosis of endometriosis. This chronic disease presents in CM an inflammatory protein pattern.

Electronic supplementary material

The online version of this article (doi:10.1186/s12014-017-9142-4) contains supplementary material, which is available to authorized users.