Rosario D'Agata

Diabetes mellitus and sperm parameters.

Because of the paucity of studies and inconsistencies regarding the impact of diabetes mellitus (DM) on semen quality, this disease is seldom looked for in the infertile patient. Recently, this view has been challenged by findings showing that DM induces subtle molecular changes that are important for sperm quality and function. This brief review shows the main sperm parameters in patients with DM and presents the mechanisms hypothesized to explain the changes observed in these patients. The data available suggest that DM alters conventional sperm parameters. In addition, DM causes histologic damage of the epididymis, with a negative impact on sperm transit. Various mechanisms may explain the sperm damage observed in patients with DM. These include endocrine disorders, neuropathy, and increased oxidative stress. Many authors suggest that DM decreases serum testosterone levels. This is associated with a steroidogenetic defect in Leydig cells. In addition, diabetic neuropathy seems to cause atonia of seminal vesicles, bladder, and urethra. Furthermore, DM is associated with an increased oxidative stress, which damages sperm nuclear and mitochondrial DNA. Finally, spermatogenesis derangement and germ cell apoptosis in type 1 DM may relate to a local autoimmune damage, whereas insulin resistance, obesity, and other related comorbidities may impair sperm parameters and decrease testosterone serum levels in patients with type 2 DM.

Sperm aneuploidy in infertile men

A recent line of research has shown that infertile male patients produce cytogenetically abnormal spermatozoa, despite a normal somatic karyotype, as a result of an altered intra-testicular environment that affects negatively the mechanisms controlling chromosome segregation during cell division. The rate of aneuploid spermatozoa production is significantly higher in patients with abnormal sperm parameters compared with those of normozoospermic subjects or infertile patients with normal sperm parameters. All chromosomes are subject to aneuploidy, although at a different rate; the heterochromosomes are more often altered than are the autosomes. A negative correlation has been reported to exist between aneuploidy and the main sperm parameters, suggesting that greater testicular damage is associated with a greater chance of chromosome malsegregation events. Abnormally-shaped spermatozoa are more likely to have chromosome abnormalities, particularly those with an enlarged head. More studies are necessary, however, to evaluate whether other types of sperm head abnormalities are also associated with an abnormal sperm chromosome complement. The possibility of retrieving testicular or epididymal spermatozoa in patients with azoospermia and using them in assisted reproduction techniques has prompted the evaluation of their chromosomal status. Studies have shown that testicular and epididymal spermatozoa have a greater rate of aneuploidy compared with that of ejaculated spermatozoa. Some authors have also shown that patients with non-obstructive azoospermia have a significantly higher sperm aneuploidy rate compared with that of patients with obstructive azoospermia. Sperm aneuploidy seems to have a negative impact on assisted reproduction technique outcome. Although it does not affect the fertilization rate, an elevated sperm aneuploidy rate is associated with a greater rate of pregnancy failure. Nevertheless, some patients with elevated sperm aneuploidy rate can still achieve a pregnancy, but with an increased risk of generating an aneuploid offspring. Thus, sperm aneuploidy evaluation is recommended in infertile patients with abnormal semen parameters, particularly if they undergo IVF programmes.

Effects of varicocelectomy on sperm DNA fragmentation, mitochondrial function, chromatin condensation, and apoptosis.

The aim of this study was to evaluate conventional semen parameters (density, morphology, and progressive motility) and the flow-cytometric parameters of DNA fragmentation, mitochondrial membrane potential, phosphatidylserine externalization, and chromatin compactness in patients with varicocele before and after varicocelectomy. Thirty men (26.5 ± 3.2 years old, range 20-32 years) with oligoasthenoteratozoospermia and grade 3 left varicocele were selected (without other causes of male infertility). Each of them underwent sperm analysis and flow cytometric evaluation before and 4 months after subinguinal microsurgical varicocelectomy (SMV). After varicocelectomy, men had significantly higher sperm density, progressive motility, and normal forms compared with baseline. They also had a significantly lower percentage of spermatozoa with low mitochondrial membrane potential. After SMV, they showed a significantly lower percentage of spermatozoa with phosphatidylserine externalization, an early sign of apoptosis. Significantly decreased percentages of spermatozoa with abnormal chromatin compactness and spermatozoa with DNA fragmentation were found after SMV compared with baseline. Subinguinal microsurgical varicocelectomy improves sperm function in oligoasthenoteratozoospermia secondary to grade 3 left varicocele. Improvements are seen in conventional parameters and biofunctional parameters not routinely evaluated.

THE KAPPA-OPIOID RECEPTOR AGONIST MR-2034 STIMULATES THE RAT HYPOTHALAMIC-PITUITARY-ADRENAL AXIS : STUDIES IN VIVO AND IN VITRO

There is increasing evidence that opiates not only have analgesic properties, but also regulate mechanisms activated during the stress response, such as the hypothalamic‐pituitary‐adrenal (HPA) axis. Indeed, opioid‐containing neurons innervate the paraventricular nucleus and the median eminence, thus modulating inputs to ACTH‐controlling neurons. In addition, dynorphin (the endogenous ligand of the kappa‐opioid receptor)‐like peptides have been found co‐localized with corticotrophin‐releasing hormone (CRH) and are believed to be co‐secreted with it in the hypophyseal portal circulation to modulate ACTH release. In this study, we evaluated the effects of the selective κ‐opioid receptor agonist MR‐2034 [(‐)‐N‐(2‐tetrahydrofurfuryl)‐normetazocine] on the HPA axis in vivo and in vitro. MR‐2034 was given intravenously to catheterized, freely moving, male Sprague‐Dawley rats and serial blood samples were collected for ACTH and corticosterone (B) measurements. We evaluated also the site of MR‐2034 action on the HPA axis in vivo, after the administration of α‐helical CRH9–41, a CRH receptor antagonist, on hypothalamic CRH, pituitary ACTH, and B release in vitro. MR‐2034 increased plasma ACTH and B levels in a dose‐related fashion and this effect was antagonized by the selective κ‐opioid receptor antagonist MR‐1452. In the presence of α‐helical CRH9–41, the responses of plasma ACTH and B to MR‐2034 were blunted significantly, suggesting that this compound activates the HPA axis through a CRH‐dependent mechanism. Accordingly, MR‐2034 stimulated hypothalamic CRH release in vitro in a concentration‐dependent fashion and this effect was antagonized dose‐dependently by MR‐1452. However, the stimulatory effect of MR‐2034 on plasma ACTH and B in vivo was not completely abolished by α‐helical CRH9–41, suggesting that an additional, CRH‐independent, mechanism was involved. Indeed, MR‐2034 was able to stimulate basal ACTH output in a dose‐dependent manner and this effect was antagonized by MR‐1452 in vitro. On the other hand, MR‐2034 did not have any effect on B release from adrenocortical cells or adrenal quarters in vitro.

Circulating Endothelial Progenitor Cells and Endothelial Microparticles in Patients With Arterial Erectile Dysfunction and Metabolic Syndrome

Blood endothelial progenitor cells (EPC) and microparticles (EMP) have been proposed as markers of endothelial dysfunction. The aim of this study was to evaluate both EPCs and EMPs in patients with arterial erectile dysfunction (ED) and metabolic syndrome (MetS). To accomplish this, 100 patients (ages 45-60 years) with ED and MetS (Adult Treatment Panel III [ATP III] 1999 criteria) and 17 healthy men (ages 44-57 years) were selected. EPC (CD45(neg)/CD34(pos)/CD144(pos)) and EMP (CD45(neg)/CD144(pos)/Annexin V(pos)) blood concentrations were evaluated by flow cytometry, before and after administration of tadalafil (20 mg) on demand for 3 months. Before treatment, EPCs and EMPs were significantly higher in patients compared with healthy men. EPCs increased significantly after tadalafil administration, whereas EMPs did not differ significantly. EPCs correlated positively or negatively with body mass index and with some cavernous artery indices, both before and after tadalafil administration. EMPs showed only positive correlations with body mass index and some cavernous artery indices, both before and after tadalafil administration. Patients with arterial ED and MetS have higher EPCs and EMPs compared with healthy men; hence, these cells may be regarded as markers of cavernous artery dysfunction. Tadalafil administration increased EPCs but not EMPs, suggesting that this compound may play a role in the endothelial repair response.

Chromosome analysis of epididymal and testicular spermatozoa in patients with azoospermia.

Azoospermic patients can now father children once spermatozoa have been retrieved from the epididymis or the testis. However, there are concerns about the risk of chromosomal abnormalities since an increase in sperm aneuploidy rate has been reported in samples from patients with abnormal sperm parameters. The purpose of this study was therefore to evaluate the sperm aneuploidy and diploidy rates for chromosomes 8, 12, 18, X and Y in spermatozoa extracted from the epididymes (n=10) or the testes (n=6) of patients with azoospermia. Ejaculated spermatozoa of healthy men (n=14) served as control. Epididymal and testicular spermatozoa had an aneuploidy rate significantly higher than that found in ejaculated spermatozoa. The aneuploidy and diploidy rates of testicular spermatozoa were higher, but not significantly different, than those found in epididymal spermatozoa. This study has shown that azoospermic patients have an increased sperm aneuploidy rate. They should therefore be given appropriate genetic counselling before entering in-vitro fertilisation programs.

Original immunophenotype of blood endothelial progenitor cells and microparticles in patients with isolated arterial erectile dysfunction and late onset hypogonadism: effects of androgen replacement therapy

Objective. Blood endothelial progenitor cells (EPCs) and endothelial microparticles (EMPs) have been proposed as markers of endothelial dysfunction. Aim of this study was to evaluate an original immunophenotype of EPCs and EMPs in patients with isolated arterial erectile dysfunction (ED) and late onset hypogonadism (LOH) before and after androgen replacement therapy. Materials and methods. Fifty patients (50–64 years) with ED and LOH were selected. EPC (CD45neg/CD34pos/CD144pos) and EMP (CD45neg/CD34neg/CD144pos) blood concentrations were evaluated by flow cytometry. Thirty patients received androgen replacement therapy (Tostrex® ProStrakan) for 6 months (group A), other 20 patients not received androgen therapy for the contraindications in their clinical history (group B). Results. After 6 months, group B showed IIEF-5 score, peak systolic velocity and acceleration time significantly worse than group A; in addition EPCs and EMPs were significantly higher in group B compared to group A. Conclusions. Patients with isolated arterial ED and LOH not treated with androgen therapy showed worst vascular parameters measured by penile Doppler and higher EPCs and EMPs compared to treated hypogonadal patients, hence, LOH appears to be an additional vascular risk factor, and these markers may be considered as predictors of cavernous artery disease. Finally, androgen therapy improves endothelial dysfunction.

Physical activity and erectile dysfunction in middle-aged men.

The prevalence of erectile dysfunction is high in men of all ages and increases greatly in the elderly. In particular, severity and prevalence both increase with aging. Because erectile dysfunction is a symptom, physicians should diagnose underlying pathologies that might lead to it instead of focusing only on finding a viable treatment. Physical inactivity negatively impacts on erectile function; experimental and clinical exercise interventions have been shown to improve sexual responses and overall cardiovascular health. Several studies have confirmed that combining 2 interventions (Mediterranean diet and physical activity) provides additional benefit to erectile function, likely via reduced metabolic disturbances (eg, inflammatory markers, insulin resistance), decreased visceral adipose tissue, and improvement in vascular function (eg, increased endothelial function). This brief review shows the main clinical evidence of benefits induced by physical activity on erectile and endothelial dysfunction. The literature shows that erectile dysfunction in middle-aged men is often an early event in endothelial damage, and physical activity is able to improve both erectile and endothelial dysfunction. There are conflicting data regarding the effects of exercise on androgen status. In clinical practice it would be recommended to add regular physical activity to balanced diet and drugs to achieve better therapeutic results.

Sperm DNA damage in patients with chronic viral C hepatitis

INTRODUCTION The aim of this study was to evaluate the conventional and biofunctional parameters of sperm in young infertile patients with Hepatitis C (HCV) infection. METHODS Forty HCV patients with primary infertility, aged 27 to 42 years (mean 36.4 years) and twenty HCV patients with secondary infertility aged 28 to 45 years (mean 35.0±2.8 years), underwent hormonal and sperm analysis in addition to the determination of reactive oxygen species (ROS) concentrations in the sperm and flow-cytometric evaluation. The following biofunctional sperm parameters were evaluated by flow cytometry: DNA fragmentation, mitochondrial membrane potential, chromatin condensation, and the rate of early apoptosis. RESULTS Overall, patients with HCV showed significantly worse median values of conventional and biofunctional sperm parameters than control subjects, including sperm density (31.7 vs. 80.4 million/ml), forward motility (9.4 vs. 25%), normal forms (15.4 vs. 24.8%), DNA fragmentation (6.6 vs. 2.2%), low MMP (45.5 vs. 8%), an early apoptosis rate (5 vs. 2.7%), and abnormal chromatin (18.9 vs. 13.9%). Finally, HCV patients had significantly higher basal (250 vs. 75×10(3)/cpm) and stimulated (550 vs. 120×10(3)/cpm) ROS levels in semen compared to control subjects. None of the examined parameters (sperm, hormonal, biofunctional and assessment of oxidative status in the semen) was significantly different between HCV patients with primary and secondary infertilities. DISCUSSION These results confirm that HCV infection has a negative impact on sperm parameters. The overlap of the results observed in the two groups of HCV patients supports the hypothesis that HCV infection may cause to alterations in sperm parameters.

Seminal Vesicles and Diabetic Neuropathy: Ultrasound Evaluation

The aim of the study was to evaluate the ultrasound characteristics of the seminal vesicles (SV) of infertile patients with diabetes and neuropathy, and possible changes in relation to duration of diabetes. Sixty infertile patients with type 2 diabetes and symptomatic neuropathy were selected. Patients were divided into 3 groups according to duration of diabetes (group A ≤ 5 years, group B between 5 and 15 years, and group C ≥ 15 years). A pathological control group of 20 infertile patients without diabetes and a real control group of 20 healthy fertile men were selected and compared. Patients underwent prostate-vesicular transrectal ultrasonography and sperm analysis. The following ultrasound parameters were recorded: 1) body anteroposterior diameter (APD); 2) fundus APD; 3) parietal thickness of the right and left SVs; 4) number of polycyclic areas within both SVs; 5) fundus-to-body ratio; 6) difference of the parietal thickness between the right and the left SVs; and 7) pre-ejaculatory and postejaculatory APD difference. All patients with diabetes had a significantly (P < .05) higher fundus-to-body ratio compared with controls. Group C had a significantly (P < .05) higher fundus-to-body ratio compared with other diabetes groups. There was no significant difference (P > .05) relative to the number of polycyclic areas in patients with diabetes and controls. All patients with diabetes had a significantly lower (P < .05) preejaculatory and postejaculatory difference in body SV APD compared with controls. Group A and group B had a similar preejaculatory and postejaculatory difference in body SV APD, whereas this difference was significantly (P < .05) lower in group C. In conclusion, infertile patients with diabetes and neuropathy have peculiar SV ultrasound features suggestive of functional atony, and duration of disease is associated with worse changes in ultrasound findings.