Pathological and immunological effects of surgically induced varicocele in juvenile and adult rats

Varicocele and testicular cord torsion: immune testicular microenvironment imbalance

The main functions of the testis, steroidogenesis and spermatogenesis, depend on the endocrine axis and systemic and local tolerance mechanisms. Infectious or non-infectious diseases may disturb testicular immune regulation causing infertility. Literature has illustrated that bacterial and viral infections lead to autoimmune infertility: either sperm antibodies or autoimmune epidydimo-orchitis. However, little is known about the association between non-infectious testicular pathologic diseases and autoimmunity. Here we review the novel aspect of varicocele and testicular cord torsion pathology linked to inflammation and discuss how immune factors could contribute to or modulate autoimmunity in ipsi- and contralateral testis.

Expression of E-cadherin and α-catenin in a varicocele-induced infertility rat model

The roles of E-cadherin and α-catenin were evaluated in the development of varicocele-induced infertility. Analysis of the association between the expression of E-cadherin/α-catenin and clinical/pathological parameters was performed. Thirty 10-week-old male rats (experimental group) were used for the experiments; the left renal vein was ligated to form a varicocele. The abdomen was incised in 30 rats (control group) and no procedure was performed on 10 rats (baseline group). The weights of the left testis, serum reactive oxygen species (ROS), testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and degenerative changes in the seminiferous tubules after 4 and 8 weeks were recorded. The expression of E-cadherin and α-catenin was evaluated by immunohistochemical (IHC) staining and Western blot analysis. The ROS increased in the 8-week experimental group, compared with the baseline and control groups (P < 0.001 for both). Additionally, FSH significantly increased in the 4- and 8-week experimental group compared with the control groups (P = 0.013 and P = 0.032, respectively). The ratio of degenerative changes in the seminiferous tubules of the experimental groups increased. The IHC staining showed that the expression of E-cadherin and α-catenin decreased in the 4- and 8-week experimental groups. Similar to the IHC staining, the experimental group had decreased reactivity on Western blot analysis. The expression of E-cadherin and α-catenin was significantly associated with the ROS and degenerative changes in the seminiferous tubules. The results of this study suggest that damage to the blood-testis barrier (BTB) is associated with varicocele-induced male infertility, and that ROS may cause damage to the BTB.

Varicocele-Induced Testicular Dysfunction May Be Associated with Disruption of Blood-Testis Barrier

The objective of this study was to examine E-cadherin and alpha-catenin expression at the junctions between adjacent Sertoli cells in testicular specimens from patients with varicocele in order to determine the presence of a possible link between blood-testis barrier and pathophysiology of varicocele. A total of 51 testicular biopsies were obtained from 28 infertile men with unilateral or bilateral varicocele. Twenty-three patients had bilateral and 5 had unilateral varicocele, Grade I varicocele was detected in 30 (59%), grade II in 15 (29%) and grade III in 6 (12%) patients. Abnormal expression of E-cadherin and alpha-catenin at the junctions between adjacent Sertoli cells was demonstrated in 100% and 90% of the patients with varicocele, respectively. In those with grade I-III varicocele, the mean E-cadherin and alpha-catenin expression were 7.6 +/- 11.4 and 39 +/- 36; 7.6 +/- 0.0 and 49 +/- 30; 8.3 +/- 9.3 and 58 +/- 33, respectively, but the difference was not significant. Reduced E-cadherin and alpha-catenin expression at the junctions between adjacent Sertoli cells may be associated with disruption of blood-testis barrier in varicocele.

The changes in testicular vascular permeability during progression of the experimental varicocele

OBJECTIVES

The vascular permeability of testicular capillaries which play a role in controlling the formation of testicular interstitial fluid was studied during the progressive course of experimental varicocele.

MATERIALS AND METHODS

The pathology was developed through partial ligation of left renal vein in four groups of rats. Controls of each group were subjected to sham surgery. After different periods of varicocele creation (1, 3, 6 and 14 weeks), animals' testes per one of the study groups were extirpated and weighed. The volume density percentages of polymorphnuclear leukocytes (PMN) per testicular blood vessels; which are markers of the increase in vascular permeability, were also estimated in both testes. To further verify the obtained findings, another group of animals received human chorionic gonadotrophin (hCG) treatment 6 weeks after varicocele creation and their histopathological sections were examined.

RESULTS

Animal testes' of (1 and 3 weeks) groups were found to be significantly heavier (p<0.05) than their controls. PMN showed accumulation in testicular blood vessels and their volume density percentages per these blood vessels in both testes were significantly higher in each study group than in those of its controls. However, these percentages showed gradual significant decline as the duration of varicocele bearing gradually increased. The hCG-treated animals revealed more accumulation of the PMN in their histopathological sections.

CONCLUSION

The present results suggest that experimental varicocele may induce an increase in testicular vascular permeability, which then decreases gradually with time. It is supposed that parallel changes in the rate of formation of testicular interstitial fluid may be accompanied. The results have also showed that the vasculature of the testis with experimental varicocele can still respond to hCG.

Ligation of the left renal vein in epm1-Wistar rats: functional and morphologic alterations in the kidneys, testes and suprarenal glands

OBJECTIVE

The ligation of the left renal vein (LLVR) in man is a controversial procedure in view of the risks of lesion to the renal parenchyma. With the objective of studying the morphologic and functional alterations caused by these lesions, we conducted experimental research with rats.

MATERIAL AND METHODS

64 male adult EPM1-WISTAR rats were used, divided into 8 groups-4 for LLRV and four for control. Each LLRV group and corresponding control group were sacrificed progressively on the 7th, 15th, 30th and 60th day after the initial surgery.

RESULTS

We found morphofunctional alterations only in animals that underwent LLRV in the four periods of sacrifice. The proteinuria creatinine in serum, testosterone in serum and serum corticosterone in serum showed practically no alteration in relation to the normal values for rats. Statistically significant severe histological lesions were found in the kidneys and testes of the LLRV groups. Lesions in the suprarenal glands were also present in these groups, but no sufficient to demonstrate statistical significance.

CONCLUSION

Based on these results we can conclude that the ligation of the left renal vein is a procedure of high risk in these animals.

Infertility due to antisperm antibodies

Immunoinfertility is an important problem, involving a significant number of infertile couples. Although the presence of antibodies on sperm has better prognostic value than those in serum or seminal plasma, it may not be the sole authentic evidence of immunoinfertility. Infertility from antisperm antibodies is likely only when they bind to a relevant sperm antigen involved in a specific fertility function. The variance in functional deficits seen in immunologic infertility is most likely related to antibodies directed at different sperm antigens or different class, subclass, or isotypes. Antibodies to FA-1 seem to be of significant importance in human immunoinfertility. In approaching couples with infertility, a high index of suspicion for antibodies is necessary to avoid misdiagnosis. In the optimal situation, all semen analyses should be screened for sperm-bound antibodies, but if this is impractical, testing should be performed on high-risk individuals (Table I). In couples in which the man has sperm-bound antibodies, and in whom there is no identifiable female factor, treatment should be instituted. Most treatments for immunoinfertility have been disappointing because of poor results, adverse effects, or high cost. Corticosteroid therapy has shown some promise in published reports (mostly poorly designed studies), but increase in pregnancy rate is modest and adverse effects may be significant. In our opinion, informed consent should be documented prior to institution of corticosteroid therapy, and subjects should be closely monitored. Advanced reproductive technologies offer a higher safety profile, and, with increasing technology, higher pregnancy rates. We recommend progressing from "low-tech" procedures, such as IUI and reserving the higher level procedures, such as IVF and ICSI, for those couples in whom pregnancy does not occur. The highest level reproductive technologies give the best current prospects for pregnancy in patients with this difficult problem but also are invasive and costly. It is hoped that further work in the laboratory will give rise to newer, safer, and less expensive effective treatments in the very near future.

The venous anatomy of experimental left varicocele: comparison with naturally occurring left varicocele in the human

OBJECTIVE

To determine the effect of experimental left varicocele on the anatomy of the veins serving the rat testis and to compare that anatomy to known patterns of vascular drainage from the human testis with and without varicocele.

DESIGN

Vascular maps were made of the effluent vessels from the rat testis in control animals and those with a 30-day experimental left varicocele. Consensus maps were arrived at and these were compared to published reports of the pertinent venous anatomy in humans with and without varicocele.

SETTING

Research laboratory.

RESULTS

The major route of blood leaving the rat testis was confirmed to be the spermatic vein, but nine common collaterals were also found to exist. Four of these collaterals became more pronounced with experimental varicocele as did several dilated perineal veins. These latter vessels all led to the iliac vein. The vasculature of the rat experimental varicocele model shares some important anatomical features with human varicocele anatomy.

CONCLUSIONS

Varicocele in humans and in the rat model causes a redistribution of blood flow from a route primarily out the spermatic vein to routes leading to the iliac vein. The redistribution is similar but not identical.

Bilateral effect of unilateral vasectomy on testicular testosterone biosynthesis

Twelve immature male dogs underwent a left vasectomy (group A). An additional five underwent a sham operation (group B). Sixteen weeks after the surgery, the bilateral mean values for caudal epididymal sperm content, the percentage of motile spermatozoa, intratesticular testosterone concentration, and testicular secretion of androgen-binding protein (in vitro) were significantly lower in group A. The mean peripheral serum testosterone responses 3 hours after human chorionic gonadotropin stimulation (3,000 IU) were significantly lower in group A than in group B (6.3 ng/mL v 9.5 ng/mL). These findings indicate a bilateral deficiency in both Leydig and Sertoli cell secretory function in unilaterally vasectomized dogs, resulting in impaired bilateral spermatogenesis and sperm maturation. The authors suggest that unilateral injuries of the vas deferens during hernia operations in children may result in bilateral testicular dysfunction.

Surgical repair of secondary right varicocele in rats with primary left varicocele: effects on fertility, testicular temperature, spermatogenesis, and sperm maturation

To evaluate whether or not dilation of the right testicular vein is a constant finding in animals with left varicocele and to illustrate its contribution to the detrimental effect of a left varicocele on the right testis, an experimental varicocele model was produced in 40 rats. Ten other rats had a sham operation (group A). Seven weeks after the operation, all 50 rats underwent laparotomy and dilation of both testicular veins was seen in 23 rats, which were randomly assigned to group B (n = 11) and group C (n = 12). One week later, groups A and C underwent sham ligation of the right testicular vein, whereas group B rats underwent resection of this vein. At 84 days after the initial operation, group C rats showed a significant reduction in right epididymal sperm content, motility, and fertilizing capacity, right testicular weight, and right testicular vs. intraabdominal temperature difference when compared with groups A and B. Since surgical repair of the secondary right varicocele improved all the parameters indicating the harmful consequences of the primary left varicocele on the right testis, it appears that dilation of the right testicular vein contributes to the detrimental effect of a left varicocele on the right testis.

Oral immunization with sperm antigens: possible therapy for sperm antibodies?

Young adult male CD-1 mice were given intraperitoneal injections (IP) of saline (controls) and pooled sperm or seminal plasma of two autoimmune infertile men and two nonautoimmune fertile men (n = 40 per treatment). Other mice received only an oral challenge with the same antigens (oral controls; n = 20 per treatment). Three weeks after the booster challenge (day 36), 20 mice in each group were orally immunized with the antigens, whereas the other 20 were not (IP controls). Cytotoxic antibody titers (immunoglobulin M) to human sperm were significantly higher in mice IP immunized with sperm or seminal plasma from autoimmune infertile men or orally immunized with autoimmune men's sperm, in contrast to the controls. Oral challenge with sperm or seminal plasma of autoimmune infertile men after the IP immunization with the same resulted in significantly decreased cytotoxic sperm antibody titers (P less than 0.001 versus oral or IP controls in sperm immunization; P less than 0.001 versus IP controls in seminal plasma immunization). Fertility was unaffected by any mode of immunization. It is concluded that, in mice, sperm and seminal plasma antigens from autoimmune infertile men are more immunogenic than those from nonautoimmune fertile men, and oral challenge with the former after an IP establishment of cytotoxic sperm immunity desensitizes the immune mice. These findings may have practical implications in the diagnosis and immunotherapy of infertile men with cytotoxic sperm antibodies.