The Effects of Experimental Left Varicocele on the Epididymis

Beta-defensin126 is correlated with sperm motility in fertile and infertile men†

A crucial function of the epididymis is providing a surface glycocalyx that is important for sperm maturation and capacitation. Defensins are antimicrobial peptides expressed in the epididymis. In the macaque epididymis, defensin beta 126 (DEFB126) is important for sperm motility, however, it is not known whether this is the case in humans. The objectives were to determine: (1) if DEFB126 on human ejaculated sperm was correlated with sperm motility in fertile and infertile men, (2) that recombinant DEFB126 could induce immature sperm motility in vitro. Immunofluorescence staining indicated that the proportion of DEFB126-positive sperm was significantly higher in motile sperm. Furthermore, the proportion of DEFB126-labeled sperm was positively correlated with sperm motility and normal morphology. Additional studies indicated that the proportion of DEFB126-positive spermatozoa in fertile volunteers was significantly higher than in volunteers with varicocele, and in infertile volunteers with semen deficiencies. To determine the role of DEFB126 on sperm motility, the DEFB126 gene was cloned and used to generate recombinant DEFB126 in H9C2 cells (rat embryonic heart myoblast cells). Deletion mutations were created into two regions of the protein, which have been linked to male infertility. Immotile testicular spermatozoa were incubated with cells expressing the different forms of DEFB126. Full-length DEFB126 significantly increased motility of co-cultured spermatozoa. However, no increase in sperm motility was observed with the mutated forms of DEFB126. In conclusion, these results support the notion that DEFB126 is important in human sperm maturation and the potential use of DEFB126 for in vitro sperm maturation.

Soluble Fibrinogen-like protein 2 plays a role in varicocele induced male infertility

Varicocele is the most common cause of male infertility. Several theories have been proposed to explain how varicocele induces infertility. The role of epididymis in male infertility is not fully well established. Fibrinogen-like protein 2 is one of serine proteases and is a potent coagulant in membranous form and immune-modulator in soluble form (sFGL-2) and expressed in the epididymis. There are no previous reports about its possible role in varicocele. This case-controlled study aimed to evaluate the seminal level of sFGL-2 in infertile men with varicocele and in men with idiopathic infertility. This study included 85 participants divided into three groups; 25 normal fertile men, 30 infertile men with varicocele and 30 infertile men of idiopathic cause. Clinical examination, Doppler ultrasound, semen analysis and measurement of seminal level of sFGL-2 were done to all participants. Seminal level of sFGL-2 was significantly elevated in infertile than normal fertile men. Seminal level of sFGL-2 showed negative correlations with sperm concentration, motility and normal morphology. Seminal level of sFGL-2 had a positive correlation with seminal liquefaction time. This study concluded that seminal level of sFGL-2 is increased in infertile men with idiopathic cause and with varicocele induced infertility and affects seminal liquefaction.

Oxidative stress in the pathophysiology of male infertility

The effects of reactive oxygen species on male fertility are governed by the oxidative paradox, defined by a delicate balance between oxidative stress and antioxidant capacity. When regulated appropriately, reactive oxygen species ensure effective function; however, when uninhibited, they represent key players in male factor infertility. Mechanisms responsible for this include oxidative destruction of sperm lipid membranes, damage to gamete DNA both by gene mutation and by direct breakdown of the DNA backbone, mitochondrial dysfunction and apoptotic cell death. Utilizing various male pathologies as case studies, we see ways in which oxidative stress has the potential to impact fertility in a negative way. Varicocele, erectile dysfunction, testicular cancer and even idiopathic male infertility highlight common mechanistic pathways, as well as subtle variations in the ways reactive oxygen species can operate. Oxidative biomarkers have emerged to better study male infertility, predict reproductive success and modify assisted reproductive technologies to minimize oxidative stress.

Pathophysiology and treatment options of varicocele: An overview

Varicocele is the most common correctable cause for male infertility, but not all men with varicocele are affected equally by this condition. The pathophysiology of varicocele-induced fertility remains ill-defined. While evidence suggests that oxidative stress remains a central factor, other mechanisms likely include scrotal hyperthermia, reflux of metabolites, hypoxia and cadmium accumulation. Microsurgical varicocelectomy remains the gold standard treatment option for infertile men with a clinically palpable varicocele and abnormal semen parameters. Newer evidence suggests a potential role for antioxidant supplementation and a meaningful role of varicocelectomy for patients destined for ART to improve pregnancy outcomes.

GYY4137 a H2S donor, attenuates ipsilateral epididymis injury in experimentally varicocele-induced rats via activation of the PI3K/Akt pathway

OBJECTIVES

The current study was aimed to investigate the effect of morpholin-4-ium 4 methoxyphenyl (morpholino) phosphinodithioate (GYY4137) on ipsilateral epididymis injury in a rat model of experimental varicocele (VC).

MATERIALS AND METHODS

Sixty Wistar rats were randomly assigned to sham, sham plus GYY4137, VC and VC plus GYY4137 groups. Sperm quality parameters, including sperm count, motility and viability were evaluated after 4 weeks. Histological changes were measured by hematoxylin and eosin staining between the groups. The oxidative stress levels were estimated by determining epididymal superoxide dismutase (SOD) and malondialdehyde (MDA). The apoptosis status and the expression of phosphatidylinositol 3'-OH kinase (PI3K)/Akt were analyzed by immunohistochemical analysis, western blot and RT-qPCR.

RESULTS

VC resulted in the decrease of sperm parameters, significant histological damage and higher levels of oxidative stress and apoptosis. Compared to the VC group, GYY4137 markedly ameliorated these observed changes. In addition, treatment with GYY4137 obviously reduced the levels of caspase-3 and Bax and increased the levels of the phosphorylation of PI3K p85 and Akt.

CONCLUSION

Our data demonstrated that GYY4137 may alleviate the sperm damage and epididymis injury in experimentally VC-induced rats by activation of the PI3K/Akt pathway.

Potential confounding factors in measurement of specific cell-free seminal mRNAs and microRNAs derived from human reproductive organs

Cell-free seminal RNA (cfs-RNA) is mixed transcripts derived from male reproductive organs, and is potential biomarker for the research and diagnosis of male reproductive-related diseases. However, some clinical factors, including age, asymptomatic Ureaplasma urealyticum (UU) infection, scrotal heat stress, abstinence period, and the storage condition of semen samples, may interfere with sperm parameters and the measurement of seminal biomarkers. Accordingly, this study was designed to evaluate the effect of above clinical factors on the measurement of cfs-RNA, aiming to lay a foundation for its research use and potential clinical application. Semen samples were collected according to the selected clinical factors. Cell-free seminal plasma was obtained by centrifugation and total RNA was extracted with TRIzol LS. Selective male reproductive organ-specific cfs-mRNAs and cfs-miRNAs were quantified by quantitative real-time PCR. The concentration and total amount of cfs-mRNAs and cfs-miRNAs in one ejaculate were calculated and compared. ACTB, DDX4 (testis-specific), WFDC9 (epididymis-specific), and miR-514a-3p (testis-specific) significantly increased after scrotal heat stress. SEMG1 (seminal vesicle-specific) showed declining tendency with the prolonged abstinence period. Age, asymptomatic UU infection, and the storage condition showed no significant impact on the measurement of cfs-RNA. These results indicate that scrotal heat stress significantly interfere with the selected cfs-RNA derived from the testis and epididymis, and abstinence period may affect the yield of cfs-mRNA from seminal vesicle, while other clinical factors has no significant impact on the measurement. Thus, heat exposure and abstinence period should be considered for the cfs-RNA measurement in its research or clinical application.

Novel insights into the pathophysiology of varicocele and its association with reactive oxygen species and sperm DNA fragmentation

Varicocele has been associated with reduced male reproductive potential. With the advances in biomolecular techniques, it has been possible to better understand the mechanisms involved in testicular damage provoked by varicocele. Current evidence suggests the central role of reactive oxygen species (ROS) and the resultant oxidative stress (OS) in the pathogenesis of varicocele-associated male subfertility although the mechanisms have not yet been fully described and it is likely to be multifactorial. Excessive ROS is associated with sperm DNA fragmentation, which may mediate the clinical manifestation of poor sperm function and fertilization outcome related to varicocele. Testing of ROS/OS and DNA fragmentation has the potential to provide additional diagnostic and prognostic information compared to conventional semen analysis and may guide therapeutic management strategies in individual patient.

Varicocele decreases epididymal neutral α-glucosidase and is associated with alteration of nuclear DNA and plasma membrane in spermatozoa

OBJECTIVE

To assess the relationship between a marker of epididymal function and both the fragmentation of the sperm nucleus and the integrity and maturity of the sperm membrane in patients with or without varicocele.

PATIENTS AND METHODS

Semen samples were obtained from men with varicocele grades II and III (n = 60) and from a control group with zoospermia defined as normal (n = 30). Samples were evaluated by a spermiogram, a hypoosmotic swelling test (HOST), neutral α-glucosidase (NAG) enzyme activity, sperm hyaluronan-binding assay (HBA) and DNA fragmentation using a sperm chromatin dispersion (SCD) test.

RESULTS

Seminal plasma NAG levels, percentage of sperm bound to hyaluronic acid, HOST-positive cells and sperm quality were significantly lower in the varicocele compared with the control group. Higher levels of sperm DNA fragmentation, as measured by SCD, were also observed in the varicocele group compared with the control group. Seminal NAG activity levels showed a strong negative correlation with DNA fragmentation and a significant positive correlation with the HBA test and the HOST.

CONCLUSIONS

Varicocele causes a reduction in NAG activity by the epididymis that is associated with damage to both the membrane and sperm nucleus and a reduction in the seminal parameters. NAG levels were correlated with the quality of the sperm membrane and nucleus. Data suggest that a reduction of fertilization capacity in men during varicocele can result from damage to both the testis and the epididymis.

Effects of supplement therapy on sperm parameters, protamine content and acrosomal integrity of varicocelectomized subjects

PURPOSE

Surgical repair of varicocele has long been a procedure to correct spermatogenesis. However, the outcome has been reported to be inadequate. We combined varicocelectomy with supplement therapy to evaluate the concurrent effect of these procedures.

METHODS

A prospective randomized controlled study was undertaken to investigate the effects of zinc sulfate, folic acid and zinc sulfate/folic acid on sperm quality, protamine content and acrosomal integrity following surgical repair of varicocele. Male subjects with palpable varicocele were included in the study and randomized into four groups. Subjects received Zinc sulfate, Folic acid, Zinc sulfate/Folic acid or placebo for 6 months. A semen sample was obtained before surgery and 3 and 6 months after surgical repair. Semen samples were evaluated for sperm parameters as well as chromatin content and acrosomal integrity.

RESULTS

Most of the evaluated parameters showed a mild improvement after varicocelectomy in the placebo group. Interestingly, co-administration of Zinc sulfate and folic acid improved most factors significantly. Folic acid administration but not zinc sulfate could increase sperm number. Hence, Zinc sulfate was better than folic acid when change in morphology was assessed, and none of them was significantly effective in sperm motility. In Zinc sulfate and Folic acid groups, protamine content and halo formation rate significantly improved.

CONCLUSIONS

We may conclude that co-administration of zinc and folic acid significantly improved sperm parameters and increased varicocelectomy outcomes. So, medical treatment with compatible drugs after surgery might be advantageous for obtaining acceptable results.

Insight into oxidative stress in varicocele-associated male infertility: part 1

Varicocele is recognized as the leading cause of male infertility because it can impair spermatogenesis through several distinct pathophysiological mechanisms. Current evidence supports oxidative stress as a key element in the pathophysiology of varicocele-related infertility, although these mechanisms have not yet been fully described. Measurement of the reactive oxygen species and other markers of oxidative stress, including the levels of the antioxidant enzymes catalase and superoxide dismutase, can provide valuable information on the extent of oxidative stress and might guide therapeutic management strategies. The testis can respond to varicocele-associated cell stressors, such as heat stress, ischaemia or production of vasodilators (for example, nitric oxide) at the expense of the generation of excessive reactive oxygen species. These responses have their own implications in exacerbating the underlying oxidative stress and on the subsequent infertility.