Heat-shock protein 70 expression in the seminal plasma of patients with chronic bacterial prostatitis and chronic prostatitis/chronic pelvic pain syndrome

Overview of seminal fluid biomarkers for the evaluation of chronic prostatitis: a scoping review

BACKGROUND

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a very common and difficult condition to evaluate, as it is a clinical diagnosis, without a measurable diagnostic "gold standard". The aim of this scoping review is to synthesize all the available data for seminal fluid biomarkers used to assess patients with CP/CPPS.

METHODS

A systematic search to identify all relevant publications was conducted on October 22, 2020 across five databases: Ovid Medline, Ovid EMBASE, PubMed, CCRT, and the CINAHL. Two independent authors screened all articles and extracted relevant data.

RESULTS

A total of 27 articles met the eligibility criteria. A majority of studies were case-control (15), with 6 observational cohorts and 6 comparative interventional studies. The total number of pooled patients included 585 patients with CP/CPPS (unspecified subtype), 371 patients with inflammatory CP/CPPS, 387 patients with non-inflammatory CP/CPPS, 354 patients with chronic bacterial prostatitis, and 432 healthy controls. Inflammatory seminal biomarkers were the most frequently studied, with IL6, IL8, TNFα and IL1β being the most promising candidates.

CONCLUSIONS

There are a number of very promising seminal biomarkers to help categorize and monitor therapies in CP/CPPS. Large multicentre studies using a shared protocol for measuring seminal biomarkers with the primary intention of biomarker validation are needed prior to clinical implementation. Identification of biomarker(s) will facilitate the etiological categorization of patients with chronic prostatitis and provide an objective framework to tailor specific therapies according to the biomarker family.

Dietary Inflammatory Index and Risk of Asthenozoospermia: A Hospital-Based Case-Controlled Study in China

Background: Evidence of associations between a pro-inflammatory diet and asthenozoospermia risk is limited. We therefore performed a case-controlled study to investigate associations between pro-inflammatory diet using dietary inflammatory index (DII) scores and asthenozoospermia risk in China.

Methods: Our hospital-based case-controlled study comprised 549 incident asthenozoospermia men and 581 healthy controls. All were interviewed at the infertility clinic in Shengjing Hospital of China Medical University from June 2020 to December 2020. DII scores were calculated based on dietary intake which were assessed using a validated food frequency questionnaire. Semen parameters were analyzed according to World Health Organization guidelines. An unconditional logistic regression model was used to estimate odds ratios (ORs) and corresponding 95% confidence intervals (CIs) for asthenozoospermia risk. The lowest tertile served as the reference category for regression analyses.

Results: After adjustment for age in the primary multivariable model, we failed to determine a significant negative association between DII and asthenozoospermia risk (for the highest tertile of DII scores compared to the lowest tertile) (OR = 0.77, 95% CI: 0.57–1.03). Similarly, non-significant associations were also identified in the multivariable model after adjusting for more potential confounders (OR = 0.86; 95% CI: 0.58–1.27). Additionally, in subgroup analyses stratified by age, body mass index, and smoking status, non-significant results were consistent with the main findings.

Conclusions: To our knowledge, this is the first study exploring this particular topic. Our research does not support an association between DII scores and asthenozoospermia risk. Further prospective studies with more DII relevant foods and nutrients are warranted to confirm our findings.

The diagnostic value of urine heat shock protein 70 and prostatic exosomal protein in chronic prostatitis

Objective

To explore the diagnostic value of the levels of prostatic exosomal protein (PSEP) and heat shock protein 70 (HSP70) in the urine of patients with chronic prostatitis (CP).

Method

Urine samples from 210 CP patients (70 cases of the USA National Institutes of Health Category II [NIH‐II], 70 NIH‐IIIa, and 70 NIH‐IIIb patients) and 70 control subjects were collected between May 2018 and February 2020. The levels of PSEP and HSP70 in urine were detected by enzyme‐linked immunosorbent assay. The differences in urine PSEP and HSP70 levels between the groups were analyzed, and receiver operating characteristic (ROC) curves were used to analyze the clinical value of PSEP and HSP70 in the diagnosis of CP.

Results

The PSEP levels of CP patients were significantly higher than those of the control group (p < 0.001), but there was no difference in PSEP levels among CP subgroups. The level of HSP70 in the urine of the NIH‐II patients was significantly lower than the levels in the NIH‐IIIa and NIH‐IIIb subgroups and the control group, but there was no difference in HSP70 levels between the NIH‐IIIa and NIH‐IIIb subgroups and the control group. ROC curve analysis results showed that the area under the curve (AUC) of PSEP for the NIH‐II, NIH‐IIIa, and NIH‐IIIb patients was 0.751, 0.776, and 0.731, respectively. The AUC of HSP70 in NIH‐II patients was 0.784, and the AUC of combined detection of PSEP and HSP70 in NIH‐II patients was 0.858.

Conclusion

Urine PSEP can be used as a marker for the diagnosis of CP, but it cannot distinguish between the various types of CP, and HSP70 can be used as a diagnostic index for NIH‐II classification.

Experimental autoimmune prostatitis: different antigens induction and antigen-specific therapy

PURPOSE

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) has uncertain etiology and lacks effective treatment. Autoimmunity is an important pathogeny, and experimental autoimmune prostatitis (EAP) models have long been used for studying CP/CPPS. This review presents the detailed current knowledge of EAP models based on evaluation criteria aspects to provide a tool for model selection in pathogenesis studies and therapeutic drug screening.

METHODS

We extensively searched the published literature on CP/CPPS and different antigen-induced EAP models focusing on the histopathology, clinical-related phenotypes, and biochemical indicators. We also cover the changes in the prostate function and other organs in EAP. Finally, we try to get some insights about antigen-based therapeutic approaches for CP/CPPS.

RESULTS

Several inciting autoantigens were reported in EAP, including male accessory gland extracts, prostate extracts (PE), prostatic steroid-binding protein, prostatic spermine-binding protein (p25), prostatic acid phosphatase, seminal vesicle secretory protein 2, and T2 peptide. All of these models mimicked histological prostatitis, however only p25- and T2-induced models developed both pelvic pain and voiding behaviors. PE immunization is the most widely used method. Diminished fertility and mental health disorders can be found in PE model. Oral and intravenous T2 peptide have been studied for antigen-specific therapy and achieved preliminary progress in EAP models.

CONCLUSIONS

PE-induced model is the most commonly used, while T2- or p25-model could serve as a promising CP/CPPS model. Antigen-specific therapy in CP/CPPS deserves further study.

The Anti-Inflammatory and Antioxidative Effects of Ningmitai Capsule in the Experimental Autoimmune Prostatitis Rat Model

Objective

Ningmitai (NMT) capsule has been widely prescribed for the treatment of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), but the mechanism remains unclear. This study aims to evaluate the therapeutic effects of the NMT capsule in the experimental autoimmune prostatitis (EAP) rat models and explore its possible mechanisms.

Methods

A total of fifty male Sprague Dawley rats were used in this study. Prostate extract was obtained for the induction of EAP rat models. The EAP rats were randomly divided into the model group, NMT low-dose group (0.45 g/kg/d), NMT medium-dose group (0.90 g/kg/d), and NMT high-dose group (1.80 g/kg/d), with six rats per group. Three NMT treatment groups were administered with the NMT capsule by gavage for 30 days. HE staining was used for histopathological analyses of prostate tissues. Western blotting was used to measure the expression of proinflammatory factors IL-1β and TNF-α. The MDA level was detected to reflect the level of oxidative stress. The bilateral dorsal root ganglia of T3/L1 to S4 were dissected to measure the substance P expression.

Results

EAP rat models were successfully constructed, in which extensive infiltration of inflammatory cells was found. Treatment of NMT capsule for 30 days and the infiltration of inflammatory cells were significantly mitigated (P < 0.05), especially in the NMT medium-dose group and NMT high-dose group. Moreover, the expression of IL-1β and the level of MDA were significantly decreased (P < 0.05). In addition, NMT treatment could significantly alleviate substance P expression in dorsal root ganglia.

Conclusion

Our findings demonstrate that the NMT capsule can alleviate inflammatory response and oxidative stress and reduce the production of substance P in EAP rats. This provides a theoretical basis for the clinical application of NMT capsule for CP/CPPS treatment.

Quantitative proteomic analysis of a genetically induced prostate inflammation mouse model via custom 4-plex DiLeu isobaric labeling

Inflammation is involved in many prostate pathologies including infection, benign prostatic hyperplasia, and prostate cancer. Preclinical models are critical to our understanding of disease mechanisms, yet few models are genetically tractable. Here, we present a comparative quantitative proteomic analysis of urine from mice with and without prostate-specific inflammation induced by conditional prostate epithelial IL-1β expression. Relative quantification and sample multiplexing was achieved using custom 4-plex N,N-dimethyl leucine (DiLeu) isobaric tags and nanoflow ultrahigh-performance liquid chromatography coupled to high-resolution tandem mass spectrometry. Each set of 4-plex DiLeu reagents allows four urine samples to be analyzed simultaneously, providing high-throughput and accurate quantification of urinary proteins. Proteins involved in the acute phase response, including haptoglobin, inter-α-trypsin inhibitor, and α1-antitrypsin 1-1, were differentially represented in the urine of mice with prostate inflammation. Mass spectrometry-based quantitative urinary proteomics represents a promising bioanalytical strategy for biomarker discovery and the elucidation of molecular mechanisms in urological research.

Inflammatory response of prostate epithelial cells to stimulation by Trichomonas vaginalis

BACKGROUND

Trichomonas vaginalis is known as the most common cause of sexually transmitted infection. However, its prevalence may have been underestimated. Trichomonads are detected in prostatic tissue in benign prostatic hyperplasia, prostatitis, and prostate cancer. Our objective was to investigate whether T. vaginalis could induce an inflammatory response in prostate epithelium.

METHODS

The cytokine production by human prostate epithelial cell (RWPE-1) activated with T. vaginalis was determined by ELISA and real-time PCR. Intracellular ROS was evaluated by flow cytometry or spectrofluorometry. The protein levels of MAP kinase, NF-κB were analyzed by Western blot. The migration of neutrophil and monocyte were performed in 24-well microplates with filter insert.

RESULTS

Incubation of cells of a human prostate epithelial cell line with a live T. vaginalis T016 isolate increased expression of the inflammatory mediators IL-1β, CCL2, and CXCL8. In addition, ROS, MAPK, and NF-κB activities increased, while inhibitors of ROS, ERK, and NF-κB reduced IL-1β production. Medium conditioned by incubation of RWPE-1 cells with T. vaginalis contained IL-1β and stimulated the migration of human neutrophils and monocytes (THP-1 cell line).

CONCLUSIONS

We conclude that T. vaginalis may increase IL-1β expression in human prostate epithelium through activation of ROS, ERK, and NF-κB, and this in turn may induce the migration of neutrophils and monocytes and lead to an inflammatory response. This research is the first attempt to confirm inflammatory reaction caused by T. vaginalis in prostate epithelial cell.

[Seminal cytokines: is quantification useful in urogenital disorders?]

Cytokines are cellular messengers which play a key role in many biological conditions such as immune defence and reproduction. During recent years analysis of seminal cytokines has become of increasing interest in various pathologies. To evaluate the current role of seminal cytokines we performed a systematic literature search within the framework of our focus group "Male Infertility during Infection and Inflammation - MIBIE". Out of 581 manuscripts we identified 124 original articles which investigated a total of 31 different cytokines. These studies can be categorized according to the following three topics: infertility, infections and chronic prostatitis. The current analysis demonstrates that seminal cytokine profiles are not associated with either semen quality or fertility; however, cytokines might be beneficial for diagnosis and monitoring therapy in patients with urogenital infections/inflammation. Further studies are needed to clarify if a single cytokine or a combination of different cytokines is necessary to evaluate different pathologies.

Bacterial infection elicits heat shock protein 72 release from pleural mesothelial cells

Heat shock protein 70 (HSP70) has been implicated in infection-related processes and has been found in body fluids during infection. This study aimed to determine whether pleural mesothelial cells release HSP70 in response to bacterial infection in vitro and in mouse models of serosal infection. In addition, the in vitro cytokine effects of the HSP70 isoform, Hsp72, on mesothelial cells were examined. Further, Hsp72 was measured in human pleural effusions and levels compared between non-infectious and infectious patients to determine the diagnostic accuracy of pleural fluid Hsp72 compared to traditional pleural fluid parameters. We showed that mesothelial release of Hsp72 was significantly raised when cells were treated with live and heat-killed Streptococcus pneumoniae. In mice, intraperitoneal injection of S. pneumoniae stimulated a 2-fold increase in Hsp72 levels in peritoneal lavage (p<0.01). Extracellular Hsp72 did not induce or inhibit mediator release from cultured mesothelial cells. Hsp72 levels were significantly higher in effusions of infectious origin compared to non-infectious effusions (p<0.05). The data establish that pleural mesothelial cells can release Hsp72 in response to bacterial infection and levels are raised in infectious pleural effusions. The biological role of HSP70 in pleural infection warrants exploration.