Does varicocelectomy affect DNA fragmentation in infertile patients?

From pathophysiology to practice: addressing oxidative stress and sperm DNA fragmentation in Varicocele-affected subfertile men

Varicocele can reduce male fertility potential through various oxidative stress mechanisms. Excessive production of reactive oxygen species may overwhelm the sperm's defenses against oxidative stress, damaging the sperm chromatin. Sperm DNA fragmentation, in the form of DNA strand breaks, is recognized as a consequence of the oxidative stress cascade and is commonly found in the ejaculates of men with varicocele and fertility issues. This paper reviews the current knowledge regarding the association between varicocele, oxidative stress, sperm DNA fragmentation, and male infertility, and examines the role of varicocele repair in alleviating oxidative-sperm DNA fragmentation in these patients. Additionally, we highlight areas for further research to address knowledge gaps relevant to clinical practice.

Effects of Varicocele Repair on Sperm DNA Fragmentation and Seminal Malondialdehyde Levels in Infertile Men with Clinical Varicocele: A Systematic Review and Meta-Analysis

PURPOSE

Varicoceles can be a source of elevated seminal oxidative stress (OS) and sperm DNA fragmentation (SDF). However, it remains unclear whether varicocele repair (VR) could reduce these parameters. This systematic review and meta-analysis (SRMA) aims to investigate the impact of VR on SDF and seminal malondialdehyde (MDA).

MATERIALS AND METHODS

A literature search was performed in Scopus, PubMed, Ovid, Embase, and Cochrane databases. This SRMA included randomized controlled trials and observational studies reporting the pre- and postoperative levels of SDF and seminal OS in infertile men with clinical varicocele that underwent VR. Subgroup analyses included techniques of VR and SDF testing. The effect size was expressed as standardized mean difference (SMD).

RESULTS

Out of 1,632 abstracts assessed for eligibility, 29 studies with 1,491 infertile men were included. The analysis showed a significant reduction in SDF after VR, compared to preoperative values (SMD -1.125, 95% confidence interval [CI] -1.410, -0.840; p<0.0001) with high inter-study heterogeneity (I²=90.965%). Reduction in SDF was evident with microsurgical technique and non-microsurgical inguinal approaches (SMD -1.014, 95% CI -1.263, -0.765; p<0.0001, and SMD -1.495, 95% CI -2.116, -0.873; p<0.0001), respectively. Reduction in SDF was significant irrespective of testing was done by sperm chromatin dispersion (SMD -2.197, 95% CI -3.187, -1.207; p<0.0001), sperm chromatin structure assay (SMD -0.857, 95% CI -1.156, -0.559; p<0.0001) or TUNEL (SMD -1.599, 95% CI -2.478, -0.719; p<0.0001). A significant decrease in seminal MDA levels was observed following VR (SMD -2.450, 95% CI -3.903 to -0.997, p=0.001) with high inter-study heterogeneity (I²=93.7%).

CONCLUSIONS

Using pre- and post-intervention data, this SRMA indicates a significant reduction in SDF and seminal MDA levels in infertile men with clinical varicocele treated with VR. These findings may have important implications for the future management of this selected group of infertile patients.

Effect of varicocele and varicocelectomy on sperm deoxyribonucleic acid fragmentation rates in infertile men with clinical varicocele

Varicocele is the leading cause of male infertility. It can affect sperm quantity and quality through various non-mutually exclusive pathophysiological mechanisms, mainly oxidative stress. Excessive production of reactive oxygen species may overwhelm the sperm's defenses against oxidative stress and harm the sperm's DNA. Excessive sperm DNA breaks, so-called sperm DNA fragmentation, result from the oxidative stress cascade and are commonly found in the ejaculates of men with varicocele and fertility-related issues. Measuring sperm DNA fragmentation can provide valuable information on the extent of harm and might help select candidates for surgical treatment. Varicocelectomy is beneficial for alleviating oxidative stress-associated infertility and improving sperm DNA integrity. However, reproductive outcomes of infertile men with elevated sperm DNA fragmentation rates and surgically treated varicoceles remain poorly studied, and there is a need for well-designed trials to determine the impact of sperm DNA fragmentation reduction on natural and medically assisted reproduction.

Does Varicocele Repair Improve Conventional Semen Parameters? A Meta-Analytic Study of Before-After Data

PURPOSE

The purpose of this meta-analysis is to study the impact of varicocele repair in the largest cohort of infertile males with clinical varicocele by including all available studies, with no language restrictions, comparing intra-person conventional semen parameters before and after the repair of varicoceles.

MATERIALS AND METHODS

The meta-analysis was performed according to PRISMA-P and MOOSE guidelines. A systematic search was performed in Scopus, PubMed, Cochrane, and Embase databases. Eligible studies were selected according to the PICOS model (Population: infertile male patients with clinical varicocele; Intervention: varicocele repair; Comparison: intra-person before-after varicocele repair; Outcome: conventional semen parameters; Study type: randomized controlled trials [RCTs], observational and case-control studies).

RESULTS

Out of 1,632 screened abstracts, 351 articles (23 RCTs, 292 observational, and 36 case-control studies) were included in the quantitative analysis. The before-and-after analysis showed significant improvements in all semen parameters after varicocele repair (except sperm vitality); semen volume: standardized mean difference (SMD) 0.203, 95% CI: 0.129-0.278; p<0.001; I²=83.62%, Egger's p=0.3329; sperm concentration: SMD 1.590, 95% CI: 1.474-1.706; p<0.001; I²=97.86%, Egger's p<0.0001; total sperm count: SMD 1.824, 95% CI: 1.526-2.121; p<0.001; I²=97.88%, Egger's p=0.0063; total motile sperm count: SMD 1.643, 95% CI: 1.318-1.968; p<0.001; I²=98.65%, Egger's p=0.0003; progressive sperm motility: SMD 1.845, 95% CI: 1.537%-2.153%; p<0.001; I²=98.97%, Egger's p<0.0001; total sperm motility: SMD 1.613, 95% CI 1.467%-1.759%; p<0.001; l2=97.98%, Egger's p<0.001; sperm morphology: SMD 1.066, 95% CI 0.992%-1.211%; p<0.001; I²=97.87%, Egger's p=0.1864.

CONCLUSIONS

The current meta-analysis is the largest to date using paired analysis on varicocele patients. In the current meta-analysis, almost all conventional semen parameters improved significantly following varicocele repair in infertile patients with clinical varicocele.

Resveratrol benefits on sperm DNA, chromatin structure and reproductive outcomes of varicocelized rats

In varicocele, the main cause of sperm DNA damage is oxidative stress (OS). Resveratrol, a polyphenol with antioxidant properties, can protect cells from injuries caused by OS. We investigated the benefits of resveratrol against reproductive damage caused by experimental varicocele induced from peripuberty. Eighty peripubertal male rats were distributed into 4 groups: sham-control (S), varicocele (V), resveratrol (R) and varicocele treated with resveratrol (VR). Varicocele was induced through the partial ligature of the left renal vein. Resveratrol was given in a daily dose of 300 mg/kg body weight (gavage). Sperm samples were collected at 100 days of age for vitality, DNA fragmentation and chromatin protamination evaluations. OS analyses were carried out. Rats from all groups were mated with healthy primiparous females for evaluation of reproductive capacity and embryonic quality. The V group showed reduction of sperm vitality, altered chromatin protamination and sperm DNA integrity and high levels of OS. The VR group showed an improvement of oxidative status, sperm vitality, DNA integrity and chromatin structure, and an enhancement in the gestational index and embryonic quality. Therefore, we showed in this experimental model that resveratrol is a promising nutraceutical adjuvant and should be deeply studied to mitigate subfertility in varicocele.

Varicocelectomy in adolescents - Does it safeguard future fertility? A single centre experience

BACKGROUND

There is paucity of literature comparing varicocelectomy to observant management amongst adolescent boys with hormonal and semen abnormalities resulting from high grade unilateral varicoceles and consequent testicular volume loss. Furthermore, it is not known whether surgical correction in such adolescents improves paternity rates in future compared to their non-operated cohort.

OBJECTIVE

The primary objective was to compare adolescent boys with unilateral high grade varicocele with associated ipsilateral testicular volume loss who were operated versus those who were not, in relation to their fertility markers (hormonal, semen parameters, and testicular volume) over a 5 year follow up period. The secondary objective was to compare the paternity rates in the respective groups over long term.

STUDY DESIGN

This was a single center, retrospective study of a prospectively maintained database conducted from 2010 to 2020, based on a standardized protocol. All adolescent boys >15 years of age (middle and late adolescence), with grade II or III unilateral varicoceles with abnormal fertility markers, who were operated (Group A) and not operated (Group B) were included. The changes in hormonal assay, sonographic assessment, semen analysis at presentation, 1st year and the 5th year follow up amongst both the groups were collated and analysed. Primary paternity rates amongst both the groups was documented by telephonic or email conversations.

RESULTS

Of the 182 boys referred for varicocele management, 110 boys (Group A -70 boys and Group B - 40 boys) satisfied our inclusion criteria and were analysed. Mean age at presentation amongst Group A boys was 16.5 years (15-18 years) and Group B boys was 16 years (15-18 years). Grade III varicoceles were more predominant amongst both the groups. There was a significant improvement in all Group A boys (operated) in the fertility markers from the time at presentation to the 5th year follow up (p < 0.001). In Group B, (boys not operated) there was no significant improvement in the above parameters. The testicular catch up growth was 92% at the 5th year follow-up in Group A and 42% in Group B. At long term follow-up, the paternity rate was 80% and 36% in Group A and B respectively.

DISCUSSION AND CONCLUSION

In adolescent boys in whom hormonal assay, testicular volumes and semen characteristics are negatively affected by high grade unilateral varicoceles, surgical correction could normalize these values, thereby safeguarding their fertility in the long term.

Expression of proapoptotic receptors Fas/Fas-L on sperm cells and levels of their soluble forms in seminal fluid from patients with varicocele

Varicocele is a condition in which the pampiniform venous plexus in the scrotum dilates abnormally during puberty, affecting testicular growth and semen parameters, and is thought to be a major cause of male infertility. The findings of researches on the presence of the Fas system in sperm are controversial. As the main triggers of apoptosis in the semen of patients with varicocele, in this study, we examined the expression of Fas/Fas-L on sperm cells and also the levels of their soluble forms in seminal plasma. Semen samples were taken from 45 patients with varicocele (study group) and 45 healthy subjects without varicocele (control group) after 3-5 days of ejaculatory abstinence. Flow cytometry was used to examine the expression of Fas and Fas ligand (Fas-L) on Sperm cells. Furthermore, soluble Fas (sFas) and soluble Fas-Ligand (sFas-L) levels in the seminal fluid were determined using an ELISA (enzyme-linked immunosorbent assay). The presence of Fas and Fas-L proteins on the sperm ejaculation surface was not found in the patients with varicocele or the control groups. However, in the case group (3.32 ± 0.31 ng/mL), sFas seminal concentrations were slightly lower than in the control group (5.50 ± 0.36 ng/mL) (p < 0.001). In varicocele patients, there was a strong negative association between seminal sFas and sperm motility. Apoptosis effects through this system on key sperm parameters were not found based on our findings. In varicocele, a reduction in sperm count and motility does not seem to be due to Fas-related mechanisms, but rather to other mechanisms.

Effect of varicocelectomy on sperm deoxyribonucleic acid fragmentation rates in infertile men with clinical varicocele: a systematic review and meta-analysis

OBJECTIVE

To evaluate the effect of varicocelectomy on sperm deoxyribonucleic acid fragmentation (SDF) rates in infertile men with clinical varicocele.

DESIGN

Systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Infertile men with clinical varicocele subjected to varicocelectomy.

INTERVENTION(S)

Systematic search using PubMed/Medline, EMBASE, Cochrane's central database, Scielo, and Google Scholar to identify relevant studies published from inception until January 2021. We included studies comparing SDF rates before and after varicocelectomy in infertile men with clinical varicocele.

MAIN OUTCOME MEASURE(S)

The primary outcome was the difference between the SDF rates before and after varicocelectomy. A meta-analysis of weighted data using random-effects models was performed. Results were reported as weighted mean differences (WMD) with 95% confidence intervals (CIs). Subgroup analyses were performed on the basis of the SDF assay, varicocelectomy technique, preoperative SDF levels, varicocele grade, follow-up time, and study design.

RESULT(S)

Nineteen studies involving 1,070 patients provided SDF data. Varicocelectomy was associated with reduced postoperative SDF rates (WMD -7.23%; 95% CI: -8.86 to -5.59; I² = 91%). The treatment effect size was moderate (Cohen's d = 0.68; 95% CI: 0.77 to 0.60). The pooled results were consistent for studies using sperm chromatin structure assay, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling, sperm chromatin dispersion test, and microsurgical varicocele repair. Subgroup analyses showed that the treatment effect was more pronounced in men with elevated vs. normal preoperative SDF levels, but the impact of varicocele grade remained equivocal. Meta-regression analysis demonstrated that SDF decreased after varicocelectomy as a function of preoperative SDF levels (coefficient: 0.23; 95% CI: 0.07 to 0.39).

CONCLUSION(S)

We concluded that pooled results from studies including infertile men with clinical varicocele indicated that varicocelectomy reduced the SDF rates. The treatment effect was greater in men with elevated (vs. normal) preoperative SDF levels. Further research is required to determine the full clinical implications of SDF reduction for these men.

Effect of varicoceles on spermatogenesis

Varicoceles are dilated veins within the spermatic cord and a relatively common occurrence in men. Fortunately, the large majority of men are asymptomatic, however, a proportion of men with varicoceles can suffer from infertility and testosterone deficiency. Sperm and testosterone are produced within the testis, and any alteration to the testicular environment can negatively affect the cells responsible for these processes. The negative impact of varicoceles on testicular function occurs mainly due to increased oxidative stress within the testicular parenchyma which is thought to be caused by scrotal hyperthermia, testicular hypoxia, and blood-testis barrier disruption. Management of varicoceles involves ligation or percutaneous embolization of the dilated veins. Repair of varicoceles can improve semen parameters and fertility, along with serum testosterone concentration. In this review, we discuss the pathophysiology of varicoceles, their impact on testicular function, and management.

Advanced Paternal Age and Sperm DNA Fragmentation: A Systematic Review

Purpose

Male ageing is often associated with defective sperm DNA remodeling mechanisms that result in poorly packaged chromatin and a decreased ability to repair DNA strand breaks. However, the impact of advanced paternal age on DNA fragmentation remains inconclusive. The aim of the present systematic review was to investigate the impact of advancing paternal age (APA) on DNA fragmentation.

Materials and Methods

We conducted a thorough search of listed publications in Scopus, PubMed, and EMBASE, in accordance with the PRISMA guidelines.

Results

We identified 3,120 articles, of which nineteen were selected for qualitative analysis, resulting in a sample of 40,668 men. Of the 19 articles evaluating the impact of APA on DFI% (DNA fragmentation Index) included, 4 were on Normozoospermic and subfertile men, 3 on normozoospermic, Oligoasthenoteratozoospermic and Teratozoospermic, 6 on fertile and infertile men, 4 on just infertile men, and 2 evaluated a general population. Seventeen of the ninrnteen studies demonstrated APA's effect and impact on DFI%.

Conclusions

Although there was no universal definition for APA, the present review suggests that older age is associated with increased DFI. In elderly men with normal semen parameters, further studies should be performed to assess the clinical implications of DFI, as a conventional semen analysis can often fail to detect an etiology for infertility.

Efficacy of varicocelectomy for sperm DNA integrity improvement: A meta-analysis

Varicocele is common among male adolescents and adults. Varicocelectomy is the major means of varicocele repair. There is evidence that varicocelectomy could decrease sperm DNA fragmentation. However, studies evaluating the efficacy of varicocelectomy for sperm DNA integrity usually have a small sample size, and there is no up-to-date meta-analysis in this area. The present meta-analysis is to evaluate the efficacy of varicocelectomy for sperm DNA integrity. A literature search was conducted to identify all relevant studies from Medline database (PubMed), Cochrane Library, and OVID Embase from the inception dates to 08 June 2020. A total of 11 prospective studies including 394 cases were included in this meta-analysis. All analysis was performed using Stata version 16.0. In the random-effect model for 11 studies, DNA fragmentation index (%) of clinical varicocele patients decreased by 5.79 (95% CI, -7.39 to -4.19) after varicocelectomy. While after excluding one study with high heterogeneity, from the results of fixed-effect model, DNA fragmentation index decreased by 6.14 (95% CI, -6.90 to -5.37) on average. Sperm DNA integrity of clinical varicocele patients was significantly improved following varicocelectomy. Therefore, it is necessary to include elevated sperm DNA fragmentation index as a molecular indicator for varicocelectomy among clinical varicocele cases.

Sperm DNA Fragmentation: A New Guideline for Clinicians

Sperm DNA integrity is crucial for fertilization and development of healthy offspring. The spermatozoon undergoes extensive molecular remodeling of its nucleus during later phases of spermatogenesis, which imparts compaction and protects the genetic content. Testicular (defective maturation and abortive apoptosis) and post-testicular (oxidative stress) mechanisms are implicated in the etiology of sperm DNA fragmentation (SDF), which affects both natural and assisted reproduction. Several clinical and environmental factors are known to negatively impact sperm DNA integrity. An increasing number of reports emphasizes the direct relationship between sperm DNA damage and male infertility. Currently, several assays are available to assess sperm DNA damage, however, routine assessment of SDF in clinical practice is not recommended by professional organizations. This article provides an overview of SDF types, origin and comparative analysis of various SDF assays while primarily focusing on the clinical indications of SDF testing. Importantly, we report four clinical cases where SDF testing had played a significant role in improving fertility outcome. In light of these clinical case reports and recent scientific evidence, this review provides expert recommendations on SDF testing and examines the advantages and drawbacks of the clinical utility of SDF testing using Strength-Weaknesses-Opportunities-Threats (SWOT) analysis.

The effects of varicocelectomy on the DNA fragmentation index and other sperm parameters: a meta-analysis

Background

Varicocele is one of the most common causes of reversible male infertility, and 15% of the varicocele patients with normal semen analysis are diagnosed as infertile. According to the current guidelines, varicocelectomy is indicated based on abnormal sperm parameters and not abnormal DNA fragmentation index (DFI) values. Thus, in this study, we performed a meta-analysis of the effects of varicocelectomy on the DFI and other conventional sperm parameters, and determined whether DFI could be used to indicate varicocelectomy for varicocele patients.

Results

Through an electronic search of the PubMed, Scopus, EBSCO, and Cochrane databases, we included 7 prospective studies including a total of 289 patients in this meta-analysis. The results showed that varicocelectomy significantly reduced DNA fragmentation (mean difference: − 6.86; 95% confidence interval [CI]: − 10.04, − 3.69; p < 0.00001) and improved sperm concentration (mean difference: 9.59; 95% CI: 7.80, 11.38; p < 0.00001), progressive motility (mean difference: 8.66; 95% CI: 6.96, 10.36; p < 0.00001), and morphology (mean difference: 2.73; 95% CI: 0,65, 4.80; p = 0.01).

Conclusion

Varicocelectomy reduced DNA fragmentation and improved sperm concentration, progressive motility, and morphology. Additionally, the analysis showed that an abnormal DFI measurement should be considered as an indication for varicocelectomy.

Alpha-lipoic acid improves sperm motility in infertile men after varicocelectomy: a triple-blind randomized controlled trial

RESEARCH QUESTION

Does supplementation with alpha-lipoic acid (ALA) enhance sperm parameters and/or the status of sperm lipid peroxidation and DNA fragmentation in men who have undergone microsurgical repair of a varicocele?

DESIGN

Individuals with a varicocele who had undergone varicocelectomy were divided into two groups receiving either 600 mg of ALA or an identical placebo for 80 days. Semen samples obtained from the participants before surgery and after completion of the course of medication were analysed and compared. Participants, clinicians and data analysts were blinded to the randomization sequence.

RESULTS

In the ALA group, total motility (P = 0.01) and progressive motility (P = 0.002) of the spermatozoa were significantly higher compared with the placebo group after surgery. Sperm lipid peroxidation and DNA damage (assessed by sperm chromatin structure assay) showed significant decreases in both the ALA and placebo groups (P ≤ 0.02) after treatment.

CONCLUSIONS

An 80-day course of ALA medication after surgical repair improves total motility and progressive motility of the spermatozoa in individuals with a varicocele.

Comparative analysis of tests used to assess sperm chromatin integrity and DNA fragmentation

Male infertility has a complex etiology, and many times, the cause is unknown. While routine semen analysis provides an overview of basic semen parameters, such as sperm concentration, motility, viability and morphology, a significant overlap of these parameters has been reported in fertile and infertile men. Moreover, conventional semen parameters do not reveal the cellular or molecular mechanisms of sperm dysfunctions leading to infertility. Therefore, sperm functional parameters, including sperm chromatin integrity, are evaluated to provide information on subtle sperm defects that are not routinely identified. Incomplete or defective sperm chromatin condensation increases the susceptibility of the sperm DNA to oxidative damage or other factors. To evaluate sperm chromatin integrity, different methods with varying degrees of diagnostic and prognostic capabilities are available. Among these assays, SCSA, TUNEL and SCD assays are most commonly used. While these assays rather evaluate the DNA directly for damages, the aniline blue and chromomycin A3 stains test for the quality of chromatin condensation. Thus, this review discusses and compares different methods used to evaluate sperm chromatin integrity and condensation, and their inclusion in the routine evaluation of the male infertility.

Interventions to Prevent Sperm DNA Damage Effects on Reproduction

Excessive oxidation and antioxidant imbalance resulting from several conditions may cause sperm DNA damage, which, in turn, affect male fertility, both natural and assisted. Sperm DNA damage transferred to the embryo might also affect the health of offspring. Several conditions associated with excessive oxidative stress are modifiable by the use of specific treatments, lifestyle changes, and averting exposure to environmental/occupational toxicants. Here, we discuss the strategies to reduce sperm DNA damage with a focus on clinical and surgical interventions.

Impact of varicocelectomy on the proteome profile of testicular tissues of rats with varicocele

Varicocele (VC) is a common cause of male infertility, but the molecular mechanisms involved in its pathogenesis are unknown. We investigated the impact of varicocelectomy (VCT) on proteome profiles in testicular tissues of rats with VC, and analysed associated target genes and signalling pathways. Sixty male rats with VC were divided into two groups: control (n = 30), and VCT (n = 30). Tissues were collected 4 weeks after sham or VCT surgery. Matrix-assisted laser desorption/ionisation time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF MS) was used to analyse the comparative proteome profiles. Kyoto Encyclopaedia of Genes and Genomes (KEGG) Orthology-Based Annotation System was used for bioinformatic analysis. Fifteen proteins were differentially expressed between control and VCT groups. These differentially expressed proteins are associated with several specific cellular processes associated with the pathogenesis of testicular growth arrest associated with VC. Furthermore, the evaluation by transmission electron micrograph showed that VCT could decrease apoptosis of spermatogenic cells in rats. Understanding such molecular pathways might provide physicians with a better insight into VC and with potential targets for treatment.

The etiologies of DNA abnormalities in male infertility: An assessment and review

The sperm DNA damage may occur in testis, genital ducts, and also after ejaculation. Mechanisms altering chromatin remodeling are abortive apoptosis and oxidative stress resulting from reactive oxygen species. Three classifications of intratesticular, post-testicular, and external factors have been correlated with increased levels of human sperm DNA damage which can affect the potential of fertility. Lifestyle, environment, medical, and iatrogenic factors might be considered to cause dysmetabolism to make distracting interactions and endocrine disrupting compounds. As a result, these may induce chromatin/DNA alteration in germ cells, which may be transmitted across generations with phenotypic consequences. Alcohol consumption may not increase the rate of sperm residual histones and protamine deficiency; however, it causes an increase in the percentage of spermatozoa with DNA fragmentation and apoptosis. In a medical problem as spinal cord injury, poor semen parameters and sperm DNA damage were reported. Infection induces reactive oxygen species production, decreases the total antioxidant capacity and sperm DNA fragmentation or antigen production that lead to sperm dysfunctions and DNA fragmentation. While reactive oxygen species generation increases with age, oxidative stress may be responsible for the age-dependent sperm DNA damage. The exposing of reproductive organs in older men to oxidative stress for a long time may produce more DNA-damaged spermatozoa than youngers. Examining the sperm chromatin quality in testicular cancer and Hodgkin's lymphoma patients prior to chemotherapy demonstrated the high incidence of DNA damage and low compaction in spermatozoa at the time of the diagnosis. In chemotherapy cycle with genotoxic agents in cancer patients, an increase in sperm DNA damage was shown after treatment. In overall, those factors occurring during the prenatal or the adult life alter the distribution of proteins associated with sperm chromatin induce changes in germ cells which can be detected in infertile patients.

Genetics and epigenetics of varicocele pathophysiology: an overview

Varicocele is found in approximately 20% of adults and adolescents and in 19-41% of men seeking treatment for infertility. It is associated with a decrease in sperm count as well as sperm motility and morphology. The currently accepted description of the pathophysiology of varicocele does not explain all its clinical manifestations; therefore, other factors such as genetic and epigenetic changes, associated with the environment, might be involved in causing infertility and decrease in sperm quality. It has been reported that the varicocele-induced deterioration of testicular function is progressive and interferes with fertility; hence, early and efficient assessment of the genetic manifestations in patients would be important for developing future medical interventions. Chromosomal disorders, mutations, polymorphisms, changes in gene expression, and epigenetic changes have all been reported to be associated with varicocele. Several studies are underway to unravel the genetic basis of this disease, as it is important to understand the origin and the aggravating factors to ensure appropriate guidance and intervention. Here, we review the available literature regarding the genetic and epigenetic changes associated with varicocele, and how these alterations are related to the different clinical manifestations of the disease.

Summary evidence on the effects of varicocele treatment to improve natural fertility in subfertile men

The objective of this review was to summarize the evidence concerning the benefit of varicocele treatment to improve natural fertility in subfertile males. We also analyzed the effect of varicocele treatment on conventional semen parameters and sperm functional tests. An electronic search to collect the data was performed using the PubMed/MEDLINE databases until July 2015. Data pooled from a variety of study designs indicate that varicocelectomy improves semen parameters in the majority of the treated men with clinical varicocele and abnormal semen parameters regardless of the chosen surgical method. Surgical varicocele repair was beneficial not only for alleviating oxidative stress-associated infertility but also to improve sperm nuclear DNA integrity. However, given the low magnitude of the effect size in sperm DNA integrity, further research is needed to elucidate its clinical significance. Conflicting results on the effect of varicocele treatment on natural fertility seem to be due to heterogeneous study designs and, more importantly, patient selection criteria. When these issues are controlled, current evidence indicates that treatment of subclinical varicocele is not warranted, as it does not seem to improve fertility. On the contrary, fair evidence indicates that varicocele treatment should be offered to infertile patients with palpable varicocele and abnormal semen parameters. This evidence supports the current guidelines issued by the American Urological Association and European Association of Urology, which state that varicocele treatment should be offered to male partners of infertile couples presenting for evaluation with clinical varicocele and semen parameters alterations.