Heat Sensing Receptor TRPV1 Is a Mediator of Thermotaxis in Human Spermatozoa

The molecular bases of sperm thermotaxis, the temperature-oriented cell motility, are currently under investigation. Thermal perception relies on a subclass of the transient receptor potential [TRP] channels, whose member TRPV1 is acknowledged as the heat sensing receptor. Here we investigated the involvement of TRPV1 in human sperm thermotaxis. We obtained semen samples from 16 normozoospermic subjects attending an infertility survey programme, testis biopsies from 6 patients with testicular germ cell cancer and testis fine needle aspirates from 6 patients with obstructive azoospermia undergoing assisted reproductive technologies. Expression of TRPV1 mRNA was assessed by RT-PCR. Protein expression of TRPV1 was determined by western blot, flow cytometry and immunofluorescence. Sperm motility was assessed by Sperm Class Analyser. Acrosome reaction, apoptosis and intracellular-Ca2+ content were assessed by flow cytometry. We found that TRPV1 mRNA and protein were highly expressed in the testis, in both Sertoli cells and germ-line cells. Moreover, compared to no-gradient controls at 31°C or 37°C (Ctrl 31°C and Ctrl 37°C respectively), sperm migration towards a temperature gradient of 31-37°C (T gradient) in non-capacitated conditions selected a higher number of cells (14,9 ± 4,2×106 cells T gradient vs 5,1± 0,3×106 cells Ctrl 31°C and 5,71±0,74×106 cells Ctrl 37°C; P = 0,039). Capacitation amplified the migrating capability towards the T gradient. Sperms migrated towards the T gradient showed enriched levels of both TRPV1 protein and mRNA. In addition, sperm cells were able to migrate toward a gradient of capsaicin, a specific agonist of TRPV1, whilst capsazepine, a specific agonist of TRPV1, blocked this effect. Finally, capsazepine severely blunted migration towards T gradient without abolishing. These results suggest that TRPV1 may represent a facilitating mediator of sperm thermotaxis

Genetic and molecular diagnostics of male infertility in the clinical practice.

Male infertility represents one of the clearest examples of complex phenotype with substantial genetic basis. It is indeed well established that genetic causes account for 10-15% of infertility cases, including chromosomal abnormalities and single-gene mutations. However, a large proportion of infertile males does not receive a clear diagnosis and thus they are reported as idiopathic or unexplained. Male (in)fertility is commonly based on standard semen analysis, which, however, cannot clearly distinguish fertile from infertile populations and therefore fails to detect any abnormality in many cases. Abnormal sperm function or specific molecular defects can be hypothesized in these cases. This review considers practical genetic and molecular diagnostic tests for male infertility, reporting on the most frequent genetic causes of male infertility and on the pros and cons of most commonly used techniques for genetic, molecular and functional sperm evaluation. Finally, this review will discuss recent advances in pharmacogenetics and new developments on sperm analysis that will form the basis for future research

Spontaneous fertility and in vitro fertilization outcome: New evidence of human papillomavirus sperm infection

Objective To evaluate the reproductive outcome of infertile couples undergoing assisted reproduction techniques (ART) with or without human papillomavirus (HPV) semen infection. Design Cross-sectional clinical study. Setting Units of andrology, reproductive medicine, and gynecology. Patient(s) A total of 226 infertile couples. Intervention(s) Male partners were evaluated by means of fluorescence in situ hybridization (FISH) for HPV on semen. After a diagnostic period, female partners underwent intrauterine insemination (IUI) or intracytoplasmic sperm injection (ICSI). Main Outcome Measure(s) Seminal parameters and FISH analysis for HPV in sperm head. Spontaneous or assisted pregnancies, live births, and miscarriages were recorded. Statistical analysis included unpaired Student t test and chi-square test. Result(s) Fifty-four male partners (23.9%) had HPV semen infection confined to sperm, confined to exfoliated cells, or in both cells. During the diagnostic period, noninfected couples showed spontaneous pregnancies. IUI and ICSI treatments were performed in, respectively, 60 and 98 noninfected and in 21 and 33 infected couples, with 38.4% and 14.2% cumulative pregnancy rates, respectively. The follow-up of pregnancies showed a higher miscarriage rate in infected couples (62.5% vs. 16.7%). Ongoing pregnancies of the latter group were characterized by HPV infection confined to exfoliated cells. Conclusion(s) A reduction in natural and assisted cumulative pregnancy rate and an increase in miscarriage rate are related to the presence of HPV at sperm level. Although the exact mechanism by which sperm infection is able to impair fertility remains unclear, this aspect is worthy of further investigations. If confirmed, these results could change the clinical and diagnostic approach to infertile couples

Plasma metabolomics in male primary and functional hypogonadism

Metabolomics proposes to unveil the molecular machinery involved in each specific disease by the comprehensive analysis of low-molecular-weight metabolites in a biological sample. This narrative mini-review analyzes previous studies applying ultra-high-performance liquid chromatography–high-resolution mass spectrometry (HRMS)-based metabolomics to highlight different metabolic pathways involved in male hypogonadism and testosterone replacement therapy, both in the case of insulin-sensitive patients with primary hypogonadism and in the case of insulin-resistant patients with functional hypogonadism. In functional hypogonadism, metabolomics revealed that different biochemical pathways are affected. In detail, glycolysis is the most important biochemical process involved in these patients. Glucose metabolism is fueled by amino acid degradation, and gluconeogenesis is widely stimulated. Some important pathways, including glycerol, are compromised. Furthermore, mitochondrial electron transport is influenced, namely, by a decrease in ATP production. On the contrary, beta-oxidation of short- and medium-chain fatty acids does not represent an energy source in hypogonadal patients. Both lactate and acetyl-CoA are converted into ketone bodies, which increased immensely. However, carnosine and β-alanine are greatly reduced. These metabolic changes are associated with increased fatigue and mental confusion. After testosterone replacement therapy, a complete restoration is achieved for only a part of the metabolites. It is of note that only in patients with functional hypogonadism treated with testosterone are ketone bodies produced at high levels, so the symptoms sometimes reported by these patients after the beginning of the therapy (difficulty in concentrating, depressed mood, brain fog, and memory impairment) might represent a specific “keto flu-like” syndrome, related to the metabolic ketonic state

Testis transcriptome analysis in male infertility: new insight on the pathogenesis of oligo-azoospermia in cases with and without AZFc microdeletion

<p>Abstract</p> <p>Background</p> <p>About 10% of cases of male infertility are due to the presence of microdeletions within the long arm of the Y chromosome (Yq). Despite the large literature covering this critical issue, very little is known about the pathogenic mechanism leading to spermatogenesis disruption in patients carrying these microdeletions. In order to identify the presence of specific molecular pathways leading to spermatogenic damage, testicular gene expression profiling was carried out by employing a microarray assay in 16 patients carrying an AZFc microdeletion or affected by idiopathic infertility. Hierarchical clustering was performed pooling the data set from 26 experiments (16 patients, 10 replicates).</p> <p>Results</p> <p>An intriguing and unexpected finding is that all the samples showing the AZFc deletion cluster together irrespectively of their testicular phenotypes. This cluster, including also four patients affected by idiopathic infertility, showed a downregulation of several genes related to spermatogenesis that are mainly involved in testicular mRNA storage. Interestingly, the four idiopathic patients present in the cluster showed no testicular expression of <it>DAZ </it>despite the absence of AZFc deletion in the peripheral blood.</p> <p>Conclusions</p> <p>Our expression profiles analysis indicates that several forms of infertility can be triggered by a common pathogenic mechanism that is likely related to alterations in testicular mRNA storage. Our data suggest that a lack of testicular DAZ gene expression may be the trigger of such mechanism. Furthermore, the presence of AZFc deletions in mosaic or the loss of function of AZFc genes in absence of Yq deletion can perhaps explain these findings. Finally, based on our data, it is intriguing to hypothesize that <it>DAZ </it>gene dysfunctions can account for a larger number of previously thought "idiopathic" infertility cases and investigation of such testicular gene dysfunction can be important to reveal the molecular determinant of infertility than are undetected when only testing Yq deletions in peripheral blood.</p

Sublingual Administration of Sildenafil Oro-dispersible Film: New Profiles of Drug Tolerability and Pharmacokinetics for PDE5 Inhibitors

Objective: Type 5 phosphodiesterase inhibitors (PDE5i) are efficient drugs used for treatment of erectile dysfunction (ED); however, a large discontinuation rate due to major side effects is reported. The aim of this study was to evaluate the possible improvement of sildenafil (Sild) pharmacokinetics associated to the sublingual administration of the new available oro-dispersible film (ODF), compared to both the oro-dispersible tablet (ODT) and the film-coated tablet (FCT) as original per os formulation.Methods:In vitro disaggregation test, dissolution test, and permeation test in specific devices to estimate the trans-mucosal absorption. In vivo analysis of serum Sild levels, by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), was performed in 20 patients with psychogenic ED receiving alternatively per os FCT or sublingual ODT or ODF, at an equal dosage (50 mg). Pharmacokinetic parameters of Sild and adverse drug reactions experienced after the dosing of each formulation were compared.Results:In vitro, ODF showed the highest time to disaggregation and an increased rate of permeation compared to both ODT and FCT (P = 0.017 and P = 0.008, respectively). In vivo, compared to both FCT and ODT, ODF showed a faster increase of serum Sild levels (serum levels at 15 min from dosing, respectively: 2.24 ± 1.4 ng/ml FCT, 0.5 ± 0.3 ng/ml ODT, and 13.5 ± 9.1 ng/ml ODF; P &lt; 0.01 and P &lt; 0.05 vs. ODF) together with a higher drug bioavailability within 60 min from dosing (relative AUC60min vs. FCT, respectively: 100.0 ± 44.9% FCT, 183.8 ± 75.4% ODT, and 304.2 ± 156.0% ODF). A trend toward lower peak serum levels was observed for ODF. Finally, ODF showed a lower prevalence of headache compared to FCT (1 vs. 35%; P &lt; 0.05) and improved pattern of flushing and nasal congestion.Conclusion: Sublingual Sild ODF improves the drug tolerability through a likely modified pharmacokinetic, suggesting a possible implication also in the clinical efficacy profile. Sublingual administration of oro-dispersible formulations may represent a strategy to ameliorate the adherence to therapy with PDE5i, particularly in patients discouraged by side effects

Prevalence of Erectile Dysfunction in Male Cancer Survivors: a Systematic Review and Meta-Analysis of Cross-Sectional Studies

Background: Sexual function is a fundamental aspect of health, well being and quality of life. In oncological male patients sexuality and erectile dysfunction (ED) can be compromise by psychological, pharmacological or physical components. Aim: We conducted a meta-analysis to estimate the prevalence of ED in all types of cancer and identify characteristics associated with ED in cancer survivors. Design and Setting: Systematic review and meta-analysis of cross-sectional studies. Method: Random effects models were used to pool the prevalence of ED as absolute estimates at three different stages (i.e., healthy, at diagnosis, and after treatment stages). A univariate meta-analysis (MA) regression including the three-level group variable as the only independent variable was used to assess the difference of prevalence of ED across the three groups. Further MA were conducted for studies involving patients at diagnosis and after treatment. Graphical comparisons of the prevalence of ED across these two stages of cancer treatment were given by a classic forest plot. Results: We included 43 studies with a total of 19,329 participants. Overall the pooled data of the included studies showed an ED prevalence of 40.72% (95%CI: 31.80-50.29) in cancer patients, with prevalence of 28.60% (95%CI: 12.10%-53.83%) at time of diagnosis and 42.70% (95%CI: 32.97%-53.03%) after treatment, across cancer locations. Conclusion: ED is particularly high in oncologic patients and may be influenced by neurovascular damage associated with treatment, hormonal therapy systemic chemo- or radiation therapy, as well as by psychological factors such as depression, anxiety, low self-esteem or issues with body image