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

Impaired release of Vitamin D in dysfunctional adipose tissue: New cues on Vitamin D supplementation in obesity

Context: Vitamin D accumulates in adipose tissue (AT) and vitamin D deficiency is frequent in obesity. Objective: We hypothesize that trafficking of vitamin D is altered in dysfunctional AT. Design, Patients, Settings: 54 normal-weight and 67 obese males were recruited in a prospective study and randomly assigned to supplementation with 50 \ub5g/week 25-hydroxyvitamin-D3 (25(OH)D) or 150 \ub5g/week vitamin D3 for 1 year, raising dosage by 50% if vitamin D-sufficiency (serum 25(OH)D>50 nomol/l), was not achieved at 6 months; 97 subjects completed the study. Methods: Vitamin D3 (D3) and 25(OH)D were quantified by HPLC-MS in control and insulin-resistant (IR) 3T3-L1 cells and subcutaneous AT (SAT) from lean and obese subjects, incubated with or without adrenaline; expression of 25-hydroxylase (CYP27A1), 1\u3b1-hydroxylase (CYP27B1) and vitamin D receptor (VDR) were analysed by real-time PCR. Results: In IR adipocytes the uptake of D3 and 25(OH)D was higher, but after adrenaline stimulation, the decrement in D3 and 25(OH)D was stronger in control cells, which also showed increased expression of CYP27A1 and CYP27B1 and higher levels of 25(OH)D. In SAT from obese subjects, the adrenaline-induced release of D3 and 25(OH)D was blunted; in both IR cells and obese SAT, protein expression of \u3b22-adrenergic receptor was reduced. Supplementation with 25-hydroxyvitamin-D3 was more effective in achieving vitamin D sufficiency in obese, but not in normal weight subjects. Conclusion: Dysfunctional AT shows a reduced catecholamine-induced release of D3 and 25(OH)D, and altered activity of vitamin D-metabolizing enzymes, for these reasons supplementation with 25-hydroxyvitamin-D3 is more effective in obese individuals

Effects of endocrine disruptors on fetal testis development, male puberty, and transition age

Purpose Endocrine disruptors (EDs) are exogenous substances able to impair endocrine system; consequently, they may cause numerous adverse effects. Over the last years, particular focus has been given to their harmful effects on reproductive system, but very little is known, especially in males. The aim of this review is to discuss the detrimental effects of EDs exposure on fetal testis development, male puberty, and transition age. Methods A search for the existing literature focusing on the impact of EDs on fetal testis development, male puberty, andrological parameters (anogenital distance, penile length, and testicular volume), and testicular cancer with particular regard to pubertal age provided the most current information available for this review. Human evidence-based reports were given priority over animal and in vitro experimental results. Given the paucity of available articles on this subject, all resources were given careful consideration. Results Information about the consequences associated with EDs exposure in the current literature is limited and often conflicting, due to the scarcity of human studies and their heterogeneity. Conclusions We conclude that current evidence does not clarify the impact of EDs on human male reproductive health, although severe harmful effects had been reported in animals. Despite controversial results, overall conclusion points toward a positive association between exposure to EDs and reproductive system damage. Further long-term studies performed on wide number of subjects are necessary in order to identify damaging compounds and remove them from the environment

Bisphenols and Male Reproductive Health: From Toxicological Models to Therapeutic Hypotheses

Bisphenols, and in particular bisphenol A (BPA), have been widely used for the production of plastic manufacts in the last 50 years. Currently, BPA is present in a variety of daily use polycarbonate plastics and epoxy resins, and dietary ingestion is considered the main route of human exposure. Accordingly, BPA is the chemical pollutant with the widest exposure in humans, involving nearly 90% of general population, according to recent studies. Concerns about BPA effects on human health date back to 1930s, when severe impact on male sexual development was suggested. Now, the acknowledged biological effects of BPA are various. In regard to human fertility, BPA has been shown to disrupt hormone signaling even at low concentrations. Results from human epidemiological studies have reported BPA interference with follicle stimulating hormone, inhibin B, estradiol, testosterone levels, and sexual function in male subjects. Moreover, recent studies have reported an association between BPA levels and reduced sperm concentration, motility, normal morphology, sperm DNA damage, and altered epigenetic pattern, resulting in trans-generational legacy of BPA effects. In this review, the recognized effects of BPA on male reproductive health are described, from the most recent issues on experimental models to epidemiological data. In addition, the very recent interest about the use of nutraceutical remedies to counteract BPA effects are discussed

SHBG(141-161) Domain-Peptide Stimulates GPRC6A-Mediated Response in Leydig and \u3b2-Langerhans cell lines

GPRC6A is acknowledged as a major regulator of energy metabolism and male fertility through the action of undercarboxylated osteocalcin (ucOCN), representing a possible therapeutic target. We recently showed that the sex hormone-binding globulin (SHBG) binds to GPRC6A through the likely involvement of the 141-161 domain. To confirm this model, here we investigated the possible binding and agonist activity of SHBG(141-161) domain-peptide (SHBG141-161) on GPRC6A. The binding of SHBG141-161 to GPRC6A and downstream dissociation from G\u3b1i(GDP) protein was computationally modelled. SHBG141-161 was obtained by solid-phase synthesis, characterized by circular dichroism (CD) and the receptor binding was assessed by displacement of ucOCN on HEK-293 cells transfected with GPRC6A gene. Agonist activity of SHBG141-161 was assessed on Leydig MA-10 and Langerhans \uf062-TC6 cell lines through the GPRC6A-mediated release of testosterone (T) and insulin. SHBG141-161 was predicted to bind to GPRC6A and to reduce the affinity for G\u3b1i(GDP) at computational level. Conformational properties and binding to GPRC6A of the synthetic SHBG141-161 were confirmed by CD and displacement experiments. SHBG141-161 stimulated cell secretion of T and insulin, with dose dependency from 10-13 to 10-11M for T release (respectively P=0,041 10-13M; P = 0,032 10-12M; P = 0,008 10-11M vs basal) and for 10-12 to 10-10M for insulin (respectively P=0,041 10-12M; P=0,007 10-11M; P=0,047 10-10M; P=0,045 vs basal). Blockade with anti GPRC6A IgG abolished the response to SHBG141-161, suggesting agonist specificity. SHBG141-161 showed stimulating activity on GPRC6A, representing a template peptide with possible therapeutic use for metabolic and endocrine disorder

PFAS Concentrations and Cardiometabolic Traits in Highly Exposed Children and Adolescents.

BACKGROUND: Residents of a large area of north-eastern Italy were exposed for decades to high concentrations of perfluoroalkyl and polyfluoroalkyl substances (PFAS) via drinking water. Despite the large amount of evidence in adults of a positive association between serum PFAS and metabolic outcomes, studies focusing on children and adolescents are limited. We evaluated the associations between serum PFAS concentrations that were quantifiable in at least 40% of samples and lipid profile, blood pressure (BP) and body mass index (BMI) in highly exposed adolescents and children. METHODS: A cross-sectional analysis was conducted in 6669 adolescents (14-19 years) and 2693 children (8-11 years) enrolled in the health surveillance program of the Veneto Region. Non-fasting blood samples were obtained and analyzed for perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorohexanesulfonic acid (PFHxS), perfluorononanoic acid (PFNA), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and triglycerides. Low-density lipoprotein cholesterol (LDL-C) was calculated. Systolic and diastolic BP were measured, and BMI z-score accounting for age and sex was estimated. The associations between ln-transformed PFAS (and categorized into quartiles) and continuous outcomes were assessed using generalized additive models. The weighted quantile sum regression approach was used to assess PFAS-mixture effects for each outcome. Analyses were stratified by gender and adjusted for potential confounders. RESULTS: Among adolescents, significant associations were detected between all investigated PFAS and TC, LDL-C, and to a lesser extent HDL-C. Among children, PFOS and PFNA had significant associations with TC, LDL-C and HDL-C, while PFOA and PFHxS had significant associations with HDL-C only. Higher serum concentrations of PFAS, particularly PFOS, were associated with lower BMI z-score. No statistically significant associations were observed between PFAS concentrations and BP. These results were confirmed by the multi-pollutant analysis. CONCLUSIONS: Our study supports a consistent association between PFAS concentration and serum lipids, stronger for PFOS and PFNA and with a greater magnitude among children compared to adolescents, and a negative association of PFAS with BMI

Interventions for preventing falls and fall-related fractures in community-dwelling older adults: A systematic review and network meta-analysis.

OBJECTIVE To compare the effectiveness of single, multiple, and multifactorial interventions to prevent falls and fall-related fractures in community-dwelling older persons. METHODS MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were systematically searched for randomized controlled trials (RCTs) evaluating the effectiveness of fall prevention interventions in community-dwelling adults aged ≥65 years, from inception until February 27, 2019. Two large RCTs (published in 2020 after the search closed) were included in post hoc analyses. Pairwise meta-analysis and network meta-analysis (NMA) were conducted. RESULTS NMA including 192 studies revealed that the following single interventions, compared with usual care, were associated with reductions in number of fallers: exercise (risk ratio [RR] 0.83; 95% confidence interval [CI] 0.77-0.89) and quality improvement strategies (e.g., patient education) (RR 0.90; 95% CI 0.83-0.98). Exercise as a single intervention was associated with a reduction in falls rate (RR 0.79; 95% CI 0.73-0.86). Common components of multiple interventions significantly associated with a reduction in number of fallers and falls rate were exercise, assistive technology, environmental assessment and modifications, quality improvement strategies, and basic falls risk assessment (e.g., medication review). Multifactorial interventions were associated with a reduction in falls rate (RR 0.87; 95% CI 0.80-0.95), but not with a reduction in number of fallers (RR 0.95; 95% CI 0.89-1.01). The following single interventions, compared with usual care, were associated with reductions in number of fall-related fractures: basic falls risk assessment (RR 0.60; 95% CI 0.39-0.94) and exercise (RR 0.62; 95% CI 0.42-0.90). CONCLUSIONS In keeping with Tricco et al. (2017), several single and multiple fall prevention interventions are associated with fewer falls. In addition to Tricco, we observe a benefit at the NMA-level of some single interventions on preventing fall-related fractures

Anticoagulant therapy for splanchnic vein thrombosis : an individual patient data meta-analysis

Robust evidence on the optimal management of splanchnic vein thrombosis (SVT) is lacking. We conducted an individual-patient meta-analysis to evaluate the effectiveness and safety of anticoagulation for SVT. Medline, Embase, and clincaltrials.gov were searched up to June 2021 for prospective cohorts or randomized clinical trials including patients with SVT. Data from individual datasets were merged, and any discrepancy with published data was resolved by contacting study authors. Three studies of a total of 1635 patients were included. Eighty-five percent of patients received anticoagulation for a median duration of 316 days (range, 1-730 days). Overall, incidence rates for recurrent venous thromboembolism (VTE), major bleeding, and mortality were 5.3 per 100 patient-years (p-y; 95% confidence interval [CI], 5.1-5.5), 4.4 per 100 p-y (95% CI, 4.2-4.6), and 13.0 per 100 p-y (95% CI, 12.4-13.6), respectively. The incidence rates of all outcomes were lower during anticoagulation and higher after treatment discontinuation or when anticoagulation was not administered. In multivariable analysis, anticoagulant treatment appeared to be associated with a lower risk of recurrent VTE (hazard ratio [HR], 0.42; 95% CI, 0.27-0.64), major bleeding (HR, 0.47; 95% CI, 0.30-0.74), and mortality (HR, 0.23; 95% CI, 0.17-0.31). Results were consistent in patients with cirrhosis, solid cancers, myeloproliferative neoplasms, unprovoked SVT, and SVT associated with transient or persistent nonmalignant risk factors. In patients with SVT, the risk of recurrent VTE and major bleeding is substantial. Anticoagulant treatment is associated with reduced risk of both outcomes.peer-reviewe

Preventing Staphylococcus aureus Sepsis through the Inhibition of Its Agglutination in Blood

Staphylococcus aureus infection is a frequent cause of sepsis in humans, a disease associated with high mortality and without specific intervention. When suspended in human or animal plasma, staphylococci are known to agglutinate, however the bacterial factors responsible for agglutination and their possible contribution to disease pathogenesis have not yet been revealed. Using a mouse model for S. aureus sepsis, we report here that staphylococcal agglutination in blood was associated with a lethal outcome of this disease. Three secreted products of staphylococci - coagulase (Coa), von Willebrand factor binding protein (vWbp) and clumping factor (ClfA) – were required for agglutination. Coa and vWbp activate prothrombin to cleave fibrinogen, whereas ClfA allowed staphylococci to associate with the resulting fibrin cables. All three virulence genes promoted the formation of thromboembolic lesions in heart tissues. S. aureus agglutination could be disrupted and the lethal outcome of sepsis could be prevented by combining dabigatran-etexilate treatment, which blocked Coa and vWbp activity, with antibodies specific for ClfA. Together these results suggest that the combined administration of direct thrombin inhibitors and ClfA-antibodies that block S. aureus agglutination with fibrin may be useful for the prevention of staphylococcal sepsis in humans