The pathophysiology of varicocele-associated male infertility

Understanding the impact of varicocele on sperm capacitation

OBJECTIVE

To study the relationship between the seminal sample quality of men with varicocele and sperm capacitation.

DESIGN

Cross-sectional observational study.

SETTING

Academic hospital.

PATIENT(S)

Seventy-six men (19 control and 57 with varicocele) were analyzed.

INTERVENTION(S)

Semen samples were submitted to a discontinuous density gradient for sperm selection. Sperm capacitation was induced using a human tubal fluid medium supplemented with bovine serum albumin.

MAIN OUTCOME MEASURE(S)

After capacitation induction, the sperm were assessed by capacitation state, computer-assisted sperm motility, mitochondrial activity, membrane integrity, acrosome reaction, and intracellular oxidative stress.

RESULT(S)

The capacitation period increased sperm motility, showing an increase in the average path velocity and a decrease in the straightness compared with sperm before capacitation (paired analysis). After capacitation, the rate of capacitated sperm, motility, and mitochondrial activity showed differences between groups (control and varicocele). The varicocele group showed lower mitochondrial activity and capacitation than the control group. On the other hand, no significant differences were observed in the other variables evaluated.

CONCLUSION(S)

Varicocele men showed less viable sperm and mitochondrial activity than control men after capacitation sperm. The induction of capacitation altered motility by increasing path velocity and decreasing straightness in all of the studied groups, evidencing the occurrence of hyperactivation.

Lifestyle-, environmental-, and additional health factors associated with an increased sperm DNA fragmentation: a systematic review and meta-analysis

INTRODUCTION

Infertility affects one in every six couples in developed countries, and approximately 50% is of male origin. In 2021, sperm DNA fragmentation (SDF) testing became an evidence-based test for fertility evaluations depicting fertility more clearly than standard semen parameters. Therefore, we aimed to summarize the potential prognostic factors of a higher SDF.

METHODS

We conducted a systematic search in three medical databases and included studies investigating any risk factors for SDF values. We calculated mean differences (MD) in SDF with 95% confidence interval (CI) for exposed and non-exposed individuals.

RESULTS

We included 190 studies in our analysis. In the group of associated health conditions, varicocele (MD = 13.62%, CI: 9.39-17.84) and impaired glucose tolerance (MD = 13.75%, CI: 6.99-20.51) had the most significant increase in SDF. Among malignancies, testicular tumors had the highest impact, with a maximum of MD = 11.3% (CI: 7.84-14.76). Among infections, the overall effects of both Chlamydia and HPV were negligible. Of lifestyle factors, smoking had the most disruptive effect on SDF - an increase of 9.19% (CI: 4.33-14.06). Different periods of sexual abstinence did not show significant variations in SDF values. Age seemed to have a more drastic effect on SDF from age 50 onwards, with a mean difference of 12.58% (CI: 7.31-17.86). Pollution also had a detrimental effect - 9.68% (CI: 6.85-12.52).

CONCLUSION

Of the above risk factors, varicocele, impaired glucose tolerance, testicular tumors, smoking, pollution, and paternal age of over 50 were associated with the highest SDF.

TRIAL REGISTRATION

CRD42021282533.

Sperm DNA fragmentation testing in clinical management of reproductive medicine

Background

Approximately 8%-12% of couples worldwide face infertility, with infertility of individuals assigned male at birth (AMAB) contributing to at least 50% of cases. Conventional semen analysis commonly used to detect sperm abnormalities is insufficient, as 30% of AMAB patients experiencing infertility show normal results in this test. From a genetic perspective, the assessment of sperm DNA fragmentation (SDF) is important as a parameter of sperm quality.

Methods

In this narrative study, we review and discuss pathophysiological causes, DNA repair mechanisms, and management of high SDF. We then summarize literature exploring the association between SDF and reproductive outcomes.

Main Findings

Recent systematic reviews and meta-analyses have revealed a significant association between high SDF in AMAB individuals and adverse reproductive outcomes including embryo development, natural conception, intrauterine insemination, and in vitro fertilization. However, the association with live birth rates and pregnancy rates following intracytoplasmic injection remains inconclusive. The disparities among quantitative assays, inconsistent reference range values, absent high-quality prospective clinical trials, and clinical heterogeneity in AMAB patients with elevated SDF represent the main limitations affecting SDF testing.

Conclusion

The evaluation and management of SDF plays an important role in a subset of AMAB infertility, but widespread integration into clinical guidelines will require future high-quality clinical trials and assay standardization.

Do sclero-embolization procedures have advantages over surgical ligature in treating varicocele in children, adolescents and adults? Results from a systematic review and meta-analysis

We aimed to systematically review complications, and recurrence rate of varicocele treatment by comparing the surgical ligature versus sclero-embolization techniques in children, adolescents and adults. The secondary outcomes were the evaluation of semen parameters and spontaneous pregnancy rate in adults. The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses framework. Continuous variables were pooled using the inverse variance of the mean difference (MD) with a fixed effect, and 95% confidence interval (CI). The incidences of complications were pooled using the Cochran-Mantel-Haenszel Method with the random effect model and reported as Odds Ratio (OR), and 95% CI. Statistical significance was set two-tail p-value < 0.05. Twenty studies were included. Incidence of postoperative hydrocele was significantly higher in the surgical ligation group (OR 3.06 95% CI 1.06-8.88, p = 0.04). Incidence of postoperative orchiepidydimitys was significantly higher in sclero-embolization group (OR 0.26 95% CI 0.08-0.85, p = 0.02). Presence of normal spermatozoa was significantly higher sclero-embolization group compared with the surgical ligature group (MD 2.54% 95% CI 0.43-4.65, p = 0.02). No difference was found in overall complications, wound infection, testis pain, surgical site hematoma, total sperm count, sperm motility, pregnancy and recurrence rate. This review confirms that current data does still not support the superiority of one type of treatment over other ones.

COVID-19 and varicocele: the possible overlap factors and the common therapeutic approaches

Varicocele is recognized as one of the main attributable causes of male infertility which can affect spermatogenesis by various pathophysiological mechanisms. Recent studies have identified oxidative stress and reduction in antioxidant, hyperthermia, hypoxia, hormonal dysfunction, and inflammatory conditions as major factors in the pathophysiology of varicocele, all of which have known direct associations with the coronavirus disease 2019 (COVID-19) and can significantly increase the risk of detrimental COVID-19-related outcomes. Emerging data have shown an association between COVID-19 and inflammation, overproduction of cytokine, and other pathophysiological processes. The present review, summarizes the current understanding of the pathophysiology of varicocele and investigates the potential correlation between the severity of COVID-19 and the varicocele disease. In addition, various possible treatments which can be effective in both diseases were examined. Despite numerous challenges associated with the prevalence of COVID-19 in healthcare systems in infected countries, special attention should be given to maintaining a high level of care for complex patients with a pre-existing disease such as varicocele and providing appropriate practical advice for optimal control of the COVID-19 disease. This article is protected by copyright. All rights reserved.

[Prevalence of male infertility in a university hospital in Morocco]

INTRODUCTION

infertility in couples has become a public health problem in recent years. It can be related to a problem in the male, female or both. Men infertility accounts for 40% of cases. In Morocco, most studies have focused on the causes and risk factors for male infertility. The purpose of our study was to assess the prevalence of male infertility and semen parameters in infertile men or in men at high risk of developing infertility in a tertiary hospital in Rabat.

METHODS

we conducted an analysis of 482 patients referred for evaluation of infertility in the couple or as part of preoperative assessment of varicocele or testicular ectopia. Demographic data, risk factors for infertility, primary or secondary infertility were recorded for each patient. Semen parameters were assessed and interpreted according to WHO standards updated in 2010 based on studies of factors associated with their disturbance.

RESULTS

the average age of patients was 35.35±8.81 years. Primary infertility was found in 61.8% of cases. The most common risk factors for infertility were tobacco followed by varicocele and infection. Spermogram was altered in 53.1% of cases. The most common abnormality was sperm vitality issues (36.9%) followed by spermatic concentration (29.7%) and morphology (29.3%). Age was the unique factor which had a significant impact on spermogram (p=0.002). Abnormalities in mobility were detected in patients ≥31 years, sperm vitality issues in patients aged 34 years, abnormalities in morphology in patients aged 35 years and concentration in patients aged 37 years. Azoospermia was found in 16.4% of cases and was mainly associated with primary infertility. Oligo-astheno-teratozoospermia was the most common association (26.2%).

CONCLUSION

male infertility is common in our context. The major risk factor is age. Mobility is the earliest parameter achieved.

The correlation between mammalian target of rapamycin (mTOR) gene expression and sperm DNA damage among infertile patients with and without varicocele

This study aimed to assess the possible correlation between mammalian target of rapamycin (mTOR) gene expression and sperm DNA damage among infertile patients with and without varicocele. The study included sixty infertile males and fifty fertile males as controls. The infertile group was subdivided into the following subgroups: thirty males with varicocele and thirty males without varicocele. All subjects underwent medical history collection, clinical examination, semen analysis, sperm DNA integrity assessment, mTOR gene expression assessment and scrotal colour Doppler ultrasound. The mean mTOR gene expression in infertile patients with varicocele (23.52 ± 14.65) was significantly higher than that in infertile patients without varicocele (12.24 ± 12.44) and fertile control subjects (3.92 ± 3.26; p = 0.003 and p < 0.001 respectively). In the infertile varicocele-positive group, mTOR gene expression showed a significant negative correlation with sperm count (p = 0.028, r = -0.400) and progressive sperm motility (p = 0.038, r = -0.381), as well as a significant positive correlation with the sperm DNA fragmentation index (DFI; p = 0.001, r = 0.578). In the infertile varicocele-negative group, mTOR gene expression showed a significant negative correlation with progressive sperm motility (p = 0.018, r = -0.429) and a significant positive correlation with sperm DFI (p < 0.001, r = 0.673). In conclusion, according to these results, there is a significant positive correlation between mTOR gene expression and sperm DFI among infertile patients with and without varicocele.

Chronic epididymitis and Grade III varicocele and their associations with semen characteristics in men consulting for couple infertility

Chronic epididymitis and varicocele are frequently observed genital disorders in men consulting for couple infertility, but their impact on semen characteristics at the time of infertility consultation is still a matter of debate. We investigated 652 male partners of couples who had their first infertility consultation between 1999 and 2015 in Argentina. Men with chronic epididymitis (n = 253), Grade III varicocele (n = 106), and both conditions (n = 125) were compared with a control group (n = 168) composed of men without these disorders or any other recognized causes of male infertility. We showed that men who presented isolated chronic epididymitis were more likely to have high percentages of low sperm motility and abnormal sperm morphology as well as a high number of white blood cells. Men with isolated Grade III varicocele had low sperm production and motility and an increased percentage of abnormal sperm morphology. Finally, men who simultaneously presented chronic epididymitis with Grade III varicocele had a low sperm motility and increased percentage of abnormal sperm morphology as well as a high number of white blood cells. Physical examination of the genital organs may identify common disorders, potentially involved as causal factors of patient's infertility. These disorders are associated with specific seminal profiles that should help in identifying the best treatment from the available therapeutic options, effectiveness, safety, and allowing as much as possible natural conception.

Relationship of Hormonal Parameters to Sperm Production in Patients with Varicocele

Idiopathic varicocele is a one of the all too often organic causes of male infertility and may can affect hormonal and spermatogenic function of the testis. We demonstrated relationships of hormonal parameters to sperm production on follicle-stimulating hormone (FSH), (LH) and testosterone blood concentrations to sperm production. The investigations involved a total of 329 patients with varicocele, at aged from 20 to 48 years, mean age 28.76 ± 0.66 years, divided into three groups: group I – patients with varicocele dextra; group II – patients with varicocele sinistra; and group III – patients with varicocele bilateralis. We established in our investigations that in 65.35% of cases the varicocele was attended coupled by with some disorders in the fertilizing ability, included including oligospermia Gr I-II (groups I and II) in 41.33% of cases, oligospermia (Gr.II-IIIgroups II and III) in 15.5% of cases and azoospermia in 8.52% of cases. In 56.83% of cases, the low sperm concentration was attended by decreasedcoupled with reduced sperm motility and velocity. Our data did not demonstrated a statistically significant increase in blood plasma T testosterone and we noted no significant correlation between the magnitude of the change in serum androgen and improvements in sperm concentration or total sperm motility per ejaculate in patients with varicocele. No significant correlations were noted in mean blood LH and FSH concentrations in patients with varicocele and in controls group.

Thiol-disulphide homoeostasis as an oxidative stress marker in men with varicocele

Oxidative stress is the most common factor leading to infertility in men with varicocele. Reactive oxygen species and other markers of oxidative stress are measured to predict the extent of oxidative stress. Thiol groups are important antioxidants and essential molecules protecting organism against the harmful effects of reactive oxygen species. Thiol-disulphide homoeostasis is a unique, easy and new method to demonstrate oxidative stress. The aim of this study was to determine thiol-disulphide homoeostasis as an oxidative stress marker in infertile men with varicocele. The hormonal profile and parameters of thiol-disulphide homoeostasis were studied in 46 infertile men with varicocele, 70 fertile men with varicocele and 37 fertile controls. Infertile men with varicocele had significantly higher disulphide concentrations and disulphide/native thiol, disulphide/total thiol and native/total thiol ratios than those of fertile men with varicocele and fertile controls. According to these results, the blood plasma of patients with varicocele contains excessive oxidative stress, even in men with normospermia, and therefore, thiol-disulphide homoeostasis may be useful as an oxidative stress marker in men with varicocele.

Should we expand the indications for varicocele treatment?

Current guidelines suggest that treatment of varicocele should be considered in patients with clinically palpable disease and abnormal semen parameters. However, the clinicians are often challenged with the decision whether to treat varicocele in patients with testicular pain or low testosterone levels. Moreover, varicocele is highly associated with DNA fragmentation due to the oxidative stress and it has been demonstrated that surgical repair of varicocele ameliorates oxidative stress markers and consequently the sperm DNA integrity. These new markers could have an adjunctive role to standard semen parameters especially when normal semen analysis is found in adult men with conventional methods. This review presents a contemporary overview of the rationale for varicocele treatment, as well as of the relationship between varicocele and other novel parameters such as DNA fragmentation index and reactive oxygen species. We will also discuss data from several recent series demonstrating that surgical treatment and especially microsurgical approach could resolve testicular pain, increase testosterone levels and fertility rate both in patients with non-obstructive azoospermia as well as in normozoospermia men. The correlation with progressive testicular failure will be also examined. We hope that this overview will provide clinicians with an evidence-based approach to managing these unanswered and conflicting topics.

Mitochondrial Genetic Variation in Iranian Infertile Men with Varicocele

Background:

Several recent studies have shown that mitochondrial DNA mutations lead to major disabilities and premature death in carriers. More than 150 mutations in human mitochondrial DNA (mtDNA) genes have been associated with a wide spectrum of disorders. Varicocele, one of the causes of infertility in men wherein abnormal inflexion and distension of veins of the pampiniform plexus is observed within spermatic cord, can increase reactive oxygen species (ROS) production in semen and cause oxidative stress and sperm dysfunction in patients. Given that mitochondria are the source of ROS production in cells, the aim of this study was to scan nine mitochondrial genes (MT-COX2, MT-tRNA^Lys , MT-ATP8, MT-ATP6, MT-COX3, MT-tRNA^Gly , MT-ND3, MT-tRNA^Arg and MT-ND4L) for mutations in infertile patients with varicocele.

Materials and Methods:

In this cross-sectional study, polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing were used to detect and identify point mutations respectively in 9 mitochondrial genes in 72 infertile men with varicocele and 159 fertile men. In brief, the samples showing altered electrophoretic patterns of DNA in the SSCP gel were sent for DNA sequencing to identify the exact nucleotide variation.

Results:

Ten type nucleotide variants were detected exclusively in mitochondrial DNA of infertile men. These include six novel nucleotide changes and four variants previously reported for other disorders.

Conclusion:

Mutations in mitochondrial genes may affect respiratory complexes in combination with environmental risk factors. Therefore these nucleotide variants probably lead to impaired ATP synthesis and mitochondrial function ultimately interfering with sperm motility and infertility.

Increased expression of the sonic hedgehog and vascular endothelial growth factor with co-localization in varicocele veins

Objectives

Varicocele is characterized by dilatation and tortuosity of the internal spermatic vein. Sonic hedgehog plays an important role in angiogenesis and vascular remodeling under hypoxic stress. We studied the relationship and distribution of SHH and vascular endothelial growth factor in internal spermatic vein in patients diagnosed with varicocele.

Methods

Specimens of 1 cm were taken from the internal spermatic vein during left varicocele repair (N = 20). The control samples of ISV were obtained from eight male patients who underwent left inguinal herniorrhaphy. We analyzed the sonic hedgehog and vascular endothelial growth factor expression and distribution by immunoblotting, immunohistochemistry, immunofluorescent staining, and confocal laser scanning microscopy. The data were analyzed using the Student’s t test.

Results

Immunoblotting showed higher expression of sonic hedgehog and vascular endothelial growth factor proteins in varicocele veins than in the control group ( P < 0.05) which located over muscle layer and endothelium was demonstrated by immunohistochemical staining. Both proteins with co-localization in the muscle layer and especially distributed in endothelium of varicocele veins were revealed under confocal microscopy.

Conclusions

These findings showed the upexpression of sonic hedgehog and vascular endothelial growth factor with co-localization in varicocele veins which imply that the reducing hypoxia or using sonic hedgehog antagonists may be helpful for this vascular disease.

[Varicocele and infertility: where do we stand in 2013?]

While the incidence of clinical varicocele is common in infertile men (about 40%), the reasons why varicocele may affect sperm parameters is still unclear. In addition, the improvement of fertility after treatment of varicocele is also a subject of debate. The purpose of this review is to get new insight into the physiopathology of varicocele, its impact on sperm parameters and the effectiveness of varicocele treatment on fertility. Treatment is likely to be effective in infertile men with clinical varicocele and impaired spermatogenesis. Even if it does not systematically lead to an improvement in sperm parameters, it may prevent further sperm degradation. In case of non-obstructive azoospermia, few studies reported a slight improvement in the process of spermatogenesis. The critical role of an adequate methodology in order to establish clinical guidelines needs to be stressed. Indeed, the huge intra-individual variability in sperm production makes the usual analysis of sperm parameters inadequate to measure treatment effectiveness. Regarding the assessment of conception, it requires not only well designed and properly sized studies but also a multivariate analysis for weighing predictive factors of success. Thus, an active scientific research is needed to better identify pathogenic agents and appropriately assess the impact of varicocele treatment.

Relationship between varicocele and sperm DNA damage and the effect of varicocele repair: a meta-analysis

Varicocele, a cause of male infertility, occurs in nearly 40% of infertile males. It has been postulated that varicoceles may cause sperm DNA damage. Sperm DNA integrity has been recognized as one of the important determinants of normal fertilization and embryo growth in natural and assisted conception. Eighty-three human studies were identified after an extensive literature search involving the role of varicoceles in sperm DNA damage. Of the 83 studies, 12 were selected that measured similar types of reactive sperm DNA damage. Seven studies determined the damage of sperm DNA in varicocele-associated patients and six studies evaluated the efficacy of varicocelectomy. One study was a duplicate because both outcomes were included. Data were analysed using RevMan software. The overall estimate showed that patients with varicoceles have significantly higher sperm DNA damage than controls, with a mean difference of 9.84% (95% CI 9.19 to 10.49; P<0.00001). A varicocelectomy can improve sperm DNA integrity, with a mean difference of -3.37% (95% CI -4.09 to -2.65; P<0.00001). In conclusion, there is increased sperm DNA damage in patients with varicoceles and varicocelectomy may be a possible treatment; however, more studies with appropriate controls are needed to confirm this finding. A varicocele is an important cause of male infertility and occurs in nearly 40% of infertile males. The recent understanding of the effect of varicoceles in male reproduction has led some researchers to postulate varicoceles as the possible cause of sperm DNA damage. Eighty-three human studies were identified after an extensive literature search involving the role of varicoceles in sperm DNA damage. Of the 83 studies, 12 were selected that measured similar types of reactive sperm DNA damage by a similar method. Seven studies determined the damage of sperm DNA in varicocele-associated patients and six studies evaluated the efficacy of varicocelectomy. One study was a duplicate because both outcomes were included. The data were then entered in the RevMan software for analysis. The overall estimate showed that patients with varicoceles have significantly higher sperm DNA damage than controls, with a mean difference of 9.84% (95% CI 9.19 to 10.49; P<0.00001). A varicocelectomy can improve sperm DNA integrity, with a mean difference of -3.37% (95% CI -4.09 to -2.65; P<0.00001). Based on the results, it can be concluded that there is increased sperm DNA damage in patients with varicoceles and that varicocelectomy may be a possible treatment; however, more studies with appropriate controls are needed to confirm this finding.

Varicocele-induced infertility: Newer insights into its pathophysiology

The association between varicoceles and male infertility has been known since the 1950s; however, the pathophysiology of the process remains uncertain. The primary proposed hypotheses involve hyperthermia, venous pressure, testicular blood flow, hormonal imbalance, toxic substances, and reactive oxygen species. It is difficult to identify a single or dominant factor, and it is likely that many of these factors contribute to the infertile phenotype seen in clinical practice. Moreover, patient lifestyle and genetic factors likely affect patient susceptibilities to the varicocele insult. While the current studies have weaknesses, they provide building blocks for futures studies into the pathophysiology of the varicocele.

DECREASED TESTICULAR EXPRESSION OF cAMP RESPONSE ELEMENT MODULATOR (CREM) IN RAT WITH VARICOCELE

This study examines the hypothesis that varicocele would impair the testicular expression of cAMP response element modulator (CREM) in experimental rats. Thirty (30) rats were selected at random, of 20 were operated as varicocele's group; of 10 were for sham-operation as controlled group, testes were removed, fixed and stained in three months. Makler Score was adopted to analyze the bore, limitan's thickness, layer number of cell, the degree of cell's maturity and average score in 200 and 100 seminiferous tubulae, respectively. CREM, HSP60 was determinated by hybridization in situ, the difference between two groups were compared. In varicocele group, seminiferous tubule's bore was decreased (101 +/- 2.2) vs 146 +/- 4.1), limitan became thicker (3.5 +/- 0.1 vs 1.9 +/- 0.2), cell's layer number was reduced (3.0 +/- 0.2 vs 5.5 +/- 0.1), cell's maturity turned to disturbance (3.6 +/- 0.3 vs 4.9 +/- 0.1), the average score was lower than controlled group (8.5 +/- 0.6 vs 16.0 +/- 1.2), they had significant differences (P < 0.001). The testicular CREM expression was significantly lower in varicocele group than in controlled one (VG2.0 +/- 0.32, SoG3.90 +/- 0.32) (p < 0.001), which was located in spermatogenous cell to spermatocyte stage. However, HSP60 expression in VG was higher than in SoG (3.85 +/- 0.3 versus 2.1 +/- 0.32) with significant differences (P < 0.001), the expression located in spermatid. Varicocele could lead to lower testicular CREM expression and breeding sperm functional lesion.

Factors controlling testis descent

Descent of the testis from an intra-abdominal site in foetal life to an extracorporeal location after birth is a mandatory developmental process to ensure that the mature testis promotes normal spermatogenesis. The two phases of transabdominal and inguinoscrotal descent occur approximately during the first and last thirds of gestation respectively. Key anatomical events to release the testis from its urogenital ridge location and to guide the free gonad into the scrotum are the degeneration of the cranio-suspensory ligament and a thickening of the gubernaculum. Androgens play a role in both these processes, particularly with respect to enabling the testis to traverse the inguinal canal in the final phase of descent. Experiments in animals suggest that androgens mediate this effect via the release of calcitonin gene-related peptide by the genitofemoral nerve, but direct evidence for such a mechanism is lacking in humans. The transabdominal phase of descent is under the control of insulin-like 3 (INSL3), a product of the Leydig cells. Definitive evidence of its role in rodent testis descent is illustrated by the phenotype of bilateral cryptorchidism in Insl3-/- null mice. Circulating levels of INSL3 are higher in boys at puberty, are undetectable in girls and are lower in boys with undescended testes. A minority also have a mutation either in the INSL3 gene or affecting its receptor gene, relaxin/insulin-like family peptide receptor 2 (LGRF8). Other factors that may play a role in testis descent include the anti-Mullerian hormone and members of the HOX gene family. Evidence that the prevalence of undescended testis may be increasing provides a phenotypic readout for the effects of postulated chemicals in the environment interfering in some way with the action of factors that control testis descent. Epidemiological studies point to profound geographical variations in prevalence in countries such as Denmark and Finland. Associations have been found with levels of chemicals labelled as endocrine disruptors being higher in breast milk samples from mothers with cryptorchid boys when compared with controls. The adverse effects of these compounds (e.g. bisphenol A) can be replicated in the offspring of dams exposed during pregnancy. A sensitive marker of an anti-androgen effect of a compound is a reduction in the anogenital distance, an anthropometric measurement that is significantly greater in males compared with females. The observation of an association between the anogenital distance in infant boys and the level of pesticides in the urine of their mothers in late gestation indicates that this has the potential to be a useful surrogate marker of the effects of environmental chemicals on testis descent in human population studies. The rightful place for the testis at birth is in the scrotum in order to provide the temperature differential essential for normal spermatogenesis. Appropriate screening programmes and early surgical intervention are the prerequisites to ensure optimal fertility in adulthood and a considerably lessened risk of testis cancer.

Clinical relevance of oxidative stress in male factor infertility: an update

Male factor has been considered a major contributory factor to infertility. Along with the conventional causes for male infertility such as varicocele, cryptorchidism, infections, obstructive lesions, cystic fibrosis, trauma, and tumors, a new, yet important cause has been identified: oxidative stress. Oxidative stress (OS) is a result of the imbalance between reactive oxygen species (ROS) and antioxidants in the body, which can lead to sperm damage, deformity and eventually male infertility. This involves peroxidative damage to sperm membrane and DNA fragmentation at both nuclear and mitochondrial levels. OS has been implicated as the major etiological factor leading to sperm DNA damage. OS-induced DNA damage can lead to abnormalities in the offspring including childhood cancer and achondroplasia. In this article, we discuss the need of ROS in normal sperm physiology, the mechanism of production of ROS and its pathophysiology in relation to male reproductive system. The benefits of incorporating antioxidants in clinical and experimental settings have been enumerated. We also highlight the emerging concept of utilizing OS as a method of contraception and the potential problems associated with it.

Lifestyle impact and the biology of the human scrotum

The possession of a scrotum to contain the male gonads is a characteristic feature of almost all mammals, and appears to have evolved to allow the testes and epididymis to be exposed to a temperature a few degrees below that of core body temperature. Analysis of cryptorchid patients, and those with varicocele suggest that mild scrotal warming can be detrimental to sperm production, partly by effects on the stem cell population, and partly by effects on later stages of spermatogenesis and sperm maturation. Recent studies on the effects of clothing and lifestyle emphasize that these can also lead to chronically elevated scrotal temperatures. In particular, the wearing of nappies by infants is a cause for concern in this regard. Together all of the evidence indirectly supports the view that lifestyle factors in addition to other genetic and environmental influences could be contributing to the secular trend in declining male reproductive parameters. The challenge will be to provide relevant and targeted experimental results to support or refute the currently circumstantial evidence.

Varicocelectomy by means of subinguinal cremasteric compartment disruption and venous ligation

OBJECTIVE

To evaluate the efficacy of addition of disruption of the cremasteric compartment to venous ligation in infertile men with varicocele and abnormal semen parameters.

MATERIAL AND METHODS

A prospective non-randomized study was undertaken in 380 infertile men with varicocele and abnormal semen parameters. They were operated on using subinguinal venous ligation with the addition of cremasteric compartment disruption on an outpatient basis.

RESULTS

Following surgery, the median values for each semen parameter were compared preoperatively and 1-year postoperatively using the Wilcoxon signed rank test. The difference in the median values was significant for all the parameters. Over a minimum 2-year follow-up period, 304 men (80%) contributed to pregnancies leading to live births.

CONCLUSIONS

The results suggest that subinguinal venous ligation with the addition of cremasteric compartment disruption is a physiological, economic and safe option for varicocele repair in men with abnormal sperm parameters. A high rate of unassisted pregnancy compared to conventional isolated venous obliteration is achievable, with minimal morbidity and recurrence.

Relationship between oxidative stress, varicocele and infertility: a meta-analysis

Varicocele is one of the leading causes of male infertility, and is present in almost 40% of infertile males. Recent understanding of the role of oxidative stress in male reproduction has led some researchers to postulate oxidative stress as the possible cause of sperm dysfunction in varicocele patients. The objective of the present study was to examine the published literature on the role of oxidative stress in patients with varicocele as the aetiology of their infertility. Twenty-three human studies were identified after an extensive search dealing with the role of oxidative stress in varicocele-associated infertility. Out of these studies, four were selected that measured similar types of reactive oxygen species (ROS) by a similar method of measurement. The data were then entered in the RevMan software for analysis. The overall estimate showed that patients have significantly higher concentrations of ROS than controls, with the mean difference being 0.73 (95% CI 0.40, 1.06, P < 0.0001). This translated to an ROS concentration of 4.37 x 10(4) cpm/20 x 10(6) spermatozoa/ml on the linear scale. Total antioxidant capacity levels were found to be significantly lower in the infertile varicocele patients, with 386 fewer trolox equivalents than the controls (95% CI -556.56-216.96, P < 0.00001). From the results, it can be concluded that there is increased oxidative stress in varicocele patients; however, more studies are needed to confirm this finding.

Generation of 4-hydroxy-2-nonenal modified proteins in testes predicts improvement in spermatogenesis after varicocelectomy

Increasing evidence suggests that testes with varicocele are exposed to oxidative stress (OS) with deterioration in spermatogenesis; however, the relationship between testicular OS and outcome after varicocelectomy is poorly understood. Levels of testicular 4-hydroxy-2-nonenal modified proteins, an OS marker, were significantly higher in responders than in nonresponders, suggesting that varicocelectomy reduces OS in testis.

Increased Expression of Hypoxia-Inducible Factor-1α in the Internal Spermatic Vein of Patients With Varicocele

PURPOSE

Varicocele is recognized as a cause of male infertility. Testis hypoxia may be one of the possible mechanisms of varicocele. We examined whether tissue hypoxia occurred in the ISV of patients with varicocele by detecting the expression of HIF-1alpha.

MATERIALS AND METHODS

The study group consisted of 8 patients with grade 3 left varicocele. The control group consisted of 6 volunteers with left indirect inguinal hernia. Using a left inguinal surgical incision, a 1 cm section of ISV was resected from each patient in both groups as specimens for immunoblotting and immunohistochemical staining of HIF-1alpha. Results were analyzed using Student's t test.

RESULTS

HIF-1alpha immunoblots from both groups revealed a single band. The relative intensity of the HIF-1alpha protein band was 10.92 +/- 2.70 in the control group and 73.15 +/- 8.93 in patients with varicocele (ie 7-fold higher).

CONCLUSIONS

HIF-1alpha expression in the ISV of patients with varicocele was significantly higher than in the control group. This directly shows that hypoxia related pathophysiological changes have occurred in the ISV of patients with varicocele and that hypoxia may have also occurred in the testicular tissue. Thus, it would be of interest to investigate whether decreasing HIF-1alpha activation and testis hypoxia could reduce the recurrence of varicocele. To our knowledge, this is the first report on HIF-1alpha expression in human ISV. Additional studies will be necessary to clarify the relationship between testis hypoxia and male infertility in patients with varicocele.