The use of ketotifen, a mast cell blocker, for treatment of oligo- and asthenozoospermia

Mast Cells in the Mammalian Testis and Epididymis-Animal Models and Detection Methods

Mast cells (MCs) are an evolutionary well-conserved type of cells, mediating and modulating allergic responses in innate immunity and tissue remodeling after chronic inflammation. Among other tissues, they inhabit both the testis and epididymis. In the testis, MCs usually appear in the interstitial compartment in humans, but not in other standard experimental models, like rats and mice. MCs seem to be responsible for testicular tissue fibrosis in different causes of infertility. Although experimental animal models follow the effect on MC activation or penetration to the interstitial tissue like in humans to some extent, there is an inconsistency in the available literature regarding experimental design, animal strain, and detection methods used. This comprehensive review offers an insight into the literature on MCs in mammalian testes and epididymides. We aimed to find the most suitable model for research on MC and offer recommendations for future experimental designs. When using in vivo animal models, tunica albuginea incorporation and standard histological assessment need to be included. Domesticated boar strains kept in modified controlled conditions exhibit the highest similarity to the MC distribution in the human testis. 3D testicular models are promising but need further fine-tuning to become a valid model for MC investigation.

Effect of ketotifen fumarate on experimental autoimmune orchitis and torsion of the spermatic cord

The aim of this work was to study effects of ketotifen fumarate (KF) on prevention of tissue damage in testes of rats with experimental autoimmune orchitis (EAO) and on the contralateral testis in a model of prolonged testicular cord torsion (TCT). Rats with EAO or TCT were injected intraperitoneally once daily with KF or saline solution (vehicle group). Incidence and severity of testicular damage were evaluated by histopathology using an EAO score or a Johnsen score. Mast cells (MC) were identified by histochemistry and quantified. In EAO model, KF significantly reduced severity of histopathological testicular damage compared to rats in the vehicle group. KF also reduced the number of testicular MC compared to vehicle group. Similarly, in TCT model, multifocal damage of the contralateral testis was observed 30 days after testicular torsion characterized by sloughing of the germinal epithelium, seminiferous tubule atrophy, and interstitial edema. Focal signs of inflammation and fibrosis of seminiferous tubular walls were also observed. In contrast, sections of contralateral testis of rats injected with KF and killed 30 days after surgery showed normal histological features. A significant decrease in the number of MC was observed in rats treated with KF compared to untreated animals. In conclusion, we demonstrated that treatment with KF reduced testicular inflammatory process and MC infiltrates in both EAO and TCT models. The results suggest a promising treatment for infertile male patients with testicular pathologies associated with inflammation and germ cell loss.

Effect of varicocelectomy and/or mast cells stabilizer on sperm DNA fragmentation in infertile patients with varicocele

This study aimed to assess the effect of varicocelectomy and/or mast cells (MCs) stabilizer on sperm DNA fragmentation in infertile men with varicocele (Vx). Overall, 120 infertile patients were randomized to three equal treatment arms; patients that underwent varicocelectomy, patients on 1 mg ketotifen twice daily for three months, and patients that underwent varicocelectomy followed with 1 mg ketotifen twice daily for three months. These patients were subjected to history taking, clinical examination, semen analysis, and estimation of sperm DNA fragmentation index (DFI). After 3 months, all investigated groups showed significant improvement regarding the mean total sperm count, sperm concentration, total sperm motility, and sperm normal forms percentage compared with the pre-treatment data. As well, the mean sperm DFI was significantly improved compared with the pre-treatment data; in men that underwent varicocelectomy (34.6% vs. 28.3%), in men on MC stabilizer only (33.4% vs. 27.8%), and in men that underwent varicocelectomy followed by MC stabilizer (34.3% vs. 25.1%). Sperm DFI improvement percentages showed the highest improvement in men that underwent varicocelectomy followed with MC stabilizer compared with the other two groups (26.8% vs. 18.2%, 16.8%). Sperm DFI improvement percentages showed significant increases in the infertile patients with Vx grade III compared to Vx grade II in all investigated groups. It is concluded that in infertile men associated with Vx and high sperm DFI, surgical repair followed with MCs stabilizer significantly improve sperm DFI compared with either surgical repair or MCs stabilizer alone.

The immune privilege of testis and gravid uterus: same difference?

The fetus in the gravid uterus and the developing spermatogenic cells in the adult testis both comprise special challenges for the host immune system. Protection of the neoantigens of the fetus and male germ cells from immune attack, defined as immune privilege, is fundamental for the propagation of species. Immune privilege is not simply the absence of leukocytes, but involves immune and non-immune cells acting synergistically together at multiple levels to create a unique tolerogenic environment. A number of the pathways are shared by the testis and gravid uterus. Amongst them steroid hormones, namely testosterone in the male and progesterone in the female, seem to function as key molecules that govern the local production of immunoregulatory factors which finally control the overall immune environment.

Ketotifen, a mast cell blocker improves sperm motility in asthenospermic infertile men

AIM

This study aimed to evaluate the efficacy of ketotifen on sperm motility of asthenospermic infertile men.

SETTING AND DESIGN

It is a prospective study designed in vivo.

MATERIALS AND METHODS

In this interventional experimental study, a total of 40 infertile couples with asthenospermic infertility factor undergoing assisted reproductive technology (ART) cycles were enrolled. The couples were randomly assigned to one of two groups at the starting of the cycle. In control group (n = 20), the men did not receive Ketotifen, while in experiment group (n = 20), the men received oraly ketotifen (1 mg Bid) for 2 months. Semen analysis, under optimal circumferences, was obtained prior to initiation of treatment. The second semen analysis was done 2-3 weeks after stopped ketotifen treatment and sperm motility was defined. Clinical pregnancy was identified as the presence of a fetal sac by vaginal ultrasound examination.

STATISTICAL ANALYSIS USED

All data are expressed as the mean ± standard error of mean (SEM). t test was used for comparing the data of the control and treated groups.

RESULTS

The mean sperm motility increased significantly (from 16.7% to 21.4%) after ketotifen treatment (P < 0.001). This sperm motility improvement was more pronounced in the primary infertility cases (P < 0.003). The rate of pregnancy was 12.5% in infertile couples that their men receiving 1 mg/twice a day ketotifen. In 52% of infertile men's semen, the percentage of sperm motility was increased from 5% to 35% and this sperm motility improvement was also observed in 33% of necrospermia (0% motility) cases.

CONCLUSION

These results suggest that ketotifen may represent as a novel therapeutic approach to improve sperm motility in the infertile men with cause of asthenospermia or necrospermia.

Zaditen (Ketotifen), as mast cell blocker, improves sperm quality, chromatin integrity and pregnancy rate after varicocelectomy

Surgery is considered the most common choice for the treatment of male infertility with clinical varicocele. Increased numbers of mast cells (MCs) have been associated with different types of infertility, including varicocele. Despite there being different reports on improved fertility following administration of MC blockers, there is no report on the effect of a MC blocker on varicocele or after varicocelectomy. Therefore, the aim of this study was to evaluate the effect of Zaditen on semen quality, protamine content, DNA damage and fertility post-surgery. The study included 103 infertile men who were referred to Isfahan Fertility and Infertility Center for varicocelectomy. Varicocele individuals were randomly divided into control (52) and treatment groups (51). Semen parameters, WBC/mL, protamine content (chromomycin A3 staining) and DNA integrity (sperm chromatin dispersion test) were assessed before and 3 months after surgery. Comparison of the aforesaid parameters between the two groups revealed significant improvement in the treatment group compared with the control group, with the exception of DNA integrity. In addition, the cumulative pregnancy significantly improved by 9 months post-surgery in the treatment group (41.17%) compared with the control group (21.15%). The results of this study, for the first time, reveal that MC blockers such as Zaditen improve semen parameters, chromatin integrity and pregnancy rates when administered as adjunct therapy post-varicocelectomy.

Oxidative stress and antioxidants for idiopathic oligoasthenoteratospermia: Is it justified?

Oxidative stress contributes to defective spermatogenesis and the poor quality of sperm associated with idiopathic male factor infertility. The aim of this study was to review the current literature on the effects of various types of antioxidant supplements in patients to improve fertilization and pregnancy rates in subfertile males with idiopathic oligoasthenoteratozoospermia (iOAT). Review of recent publications through PubMed and the Cochrane database. Oxidative stress is implicated in impaired spermatogenesis leading to the poor semen parameters and increased DNA damage and apoptosis in iOAT. Strategies to modulate the level of oxidative stress within the male reproductive tract include the use of oral antioxidant compounds to reinforce the body's defence against oxidative damage. In our evaluation, carnitines were considered the most established pharmacotherapeutic agent to treat iOAT, as evidence and data concerning carnitine supplementation have been shown to be most consistent and relevant to the population of interest. Other therapies, such as combined vitamin E and C therapy, are still considered controversial as vitamin C can act as a pro-oxidant in certain instances and the results of randomized controlled trials have failed to show significant benefit to sperm parameters and pregnancy rates. There is a need for further investigation with randomized controlled studies to confirm the efficacy and safety of antioxidant supplementation in the medical treatment of idiopathic male infertility as well as the need to determine the dosage required to improve semen parameters, fertilization rates and pregnancy outcomes in iOAT.

Protease activated receptor 2 and epidermal growth factor receptor are involved in the regulation of human sperm motility

AIM

To investigate mechanisms of tryptase-induced reduction of sperm motility and explore whether epidermal growth factor receptor (EGF-R) and protease activated receptor 2 (PAR-2)- associated pathways are involved.

METHODS

Fresh semen was collected from healthy donors (n = 15). Semen parameters and quality were assessed in accordance with the World Health Organization (WHO) criteria. Swim-up sperm were fixed and subjected to immunocytochemistry and immunoelectronmicroscopy with specific antibodies directed against PAR-2 and EGF-R. Protein extractions from swim-up spermatozoa were analyzed by Western blotting with antibodies for both receptors. Motility of spermatozoa was evaluated by computer-assisted semen analysis.

RESULTS

Immunocytochemistry found PAR-2 and EGF-R in approximately 30% of examined human ejaculated spermatozoa. Both receptors were localized in the plasma membrane. Like tryptase, the PAR-2 synthetic agonist SLIGKV reduced sperm motility, and this effect was inhibited by application of two specific EGF-R pathway blockers (AG1478 and PD168393).

CONCLUSION

The observed reduction of sperm motility by tryptase through the PAR-2 receptor involves EGF-R pathways.

Ketotifen improves sperm motility and sperm morphology in male patients with leukocytospermia and unexplained infertility

In an open, uncontrolled study, the effect of 12 weeks of daily administration of ketotifen, an antihistamine-like drug with a mast cell stabilizing effect, on the semen quality of 55 men with leukocytospermia and unexplained infertility was examined. After 4 weeks of treatment, white blood cell count dramatically diminished and was accompanied by a significant improvement in sperm motility. A significant increase of morphologically normal sperm cells was observed at 8 weeks of treatment, and these changes remained until at least 4 weeks after the end of treatment.

The mast cells in semen: their effects on sperm motility

This study was conducted to evaluate any possible association between mast cells and sperm concentration, morphology, and motility. The study comprised 400 patients who had applied for semen analysis. To evaluate mast cells, 6 smear slides were prepared for each subject and stained with 1% toluidin blue-pyronine (pH 4). The slides revealing any mast cells were labeled as mast+. Concentration and motility was evaluated through a Makler chamber. Kruger's strict criteria were used in morphometric analysis. The mean age of 86 mast+ cases (21% of total patients) was 31+/-6.7; progressive sperm motility rate was 33+/-21.2. The mean concentration was 32+/-30.2 x 10(6)/mL, and normal sperm percentage was 11.8+/-6.5. Progressive sperm motility rate in the mast- cases were 53+/-25. The mean age of mast cell+ patients was higher than that of mast cell- patients (t=3.57, p<.001), while they had lower sperm concentration (p>.05) and lower normal morphologic sperm rate (t=2.26, p<.024), compared to mast cell- patients. The relation between mast cell+ and mast cell- cases and sperm progressive motility was statistically significant (t=6.44, p<.001). It was concluded that sperm parameters were negatively affected by mast cells.

Proliferative action of mast-cell tryptase is mediated by PAR2, COX2, prostaglandins, and PPARgamma : Possible relevance to human fibrotic disorders

Mast-cell products can stimulate fibroblast proliferation, implying that these cells are key players in fibrosis. One mast-cell product, the serine protease tryptase, is known to activate protease-activated receptor 2 (PAR2) and cause proliferation of fibroblasts. We found that recombinant tryptase, human mast-cell (HMC-1) supernatant, which contains tryptase, and the PAR2-activating peptide SLIGKV exert fibroproliferative actions in human fibroblasts. Here we report insights into this action, which after activation of PAR2 leads to increased expression of cyclooxygenase 2 (COX2), a key enzyme in the biosynthesis of prostaglandins, and consequently to enhanced prostaglandin synthesis. Subsequent cell proliferation is mediated by the prostaglandin 15-deoxy-Delta(12,14)-prostaglandin J(2), which acts via the nuclear peroxisome proliferator-activated receptor gamma (PPARgamma). Fibroblast proliferation induced by tryptase and PAR2 agonist peptide can be blocked by antagonists of COX2 and PPARgamma, implying that the proliferative effect of tryptase is PAR2-initiated but depends on COX2, 15-deoxy-Delta(12,14)-prostaglandin J(2), and PPARgamma. This previously uncharacterized pathway could be of relevance for human fibrotic diseases. For instance, increased numbers of activated mast cells are correlated with fibrosis in testes of infertile men. In these cases all components of the signaling pathway of tryptase were detected as well as expression of COX2. Therefore, our study describes as-yet-unknown interactions between mast cells and fibroblasts, which could be relevant for human fibrotic diseases.

Treatment of oligoasthenozoospermia with tranilast, a mast cell blocker, after long-term administration

The authors retrospectively examined whether long-term administration of tranilast improves semen parameters in severe oligoasthenozoospermia. Fifty-two patients presenting with sperm concentration of less than 10 x 10(6) sperm/mL were enrolled. Subjects were partitioned into 3 groups as follows: patients displaying an atrophic testis with elevated (FSH) (group 1), patients exhibiting normal testicular volume with elevated FSH (group 2), and patients with normal testicular volume and normal FSH levels (group 3). Tranilast (300mg/day) was administered until pregnancy was achieved or for a period of up to 12 months. Sperm concentration was significantly increased at 3 months in 16 subjects (44%) in groups 1 and 3. In group 2, sperm concentration was increased at 12 months (5 of 16 subjects; 31%). Total sperm count was obviously elevated at 3 months in groups 1 and 2, and at 6 months in group 3. Six pregnancies were achieved via natural intercourse. Tranilast, a mast cell blocker, demonstrates a certain clinical benefit in terms of improvement of semen parameters involving severe oligoasthenozoospermia, but it does not appear to afford clinical benefit in long-term administration.

Management strategies for male factor infertility

Although modern assisted reproduction techniques contribute a lot to overcoming severe male factor infertility, application of these methods in every infertile couple would represent an over-treatment. Therefore, conventional treatment modalities are still the first approach to male fertility disorders. Apart from assisted reproduction techniques, these include surgical procedures and the administration of drugs. Causal treatment regimens of proven effectiveness are only available for patients with infertility resulting from hypogonadotrophic hypogonadism. Drug treatment of retrograde ejaculation is also effective. Inconsistent results have been obtained with empirical treatment including antiestrogens, androgens, aromatase-inhibitors, mast cell blockers, zinc and pentoxifylline. Anti-inflammatory and immunosuppressive therapy as well as treatment with antioxidants in the presence of reactive oxygen species has not yet been demonstrated to be effective by controlled studies but represent at least a rational approach which should be investigated more thoroughly. High dosage administration of follicle stimulating hormone aimed particularly at improving disturbed sperm structures, and the combination of tamoxifen with androgens, may be promising developments. A careful diagnostic work-up is necessary before any andrological treatment is commenced so that adequate treatment options can be selected for individual patients.

The treatment with tranilast, a mast cell blocker, for idiopathic oligozoospermia

Although many drug treatments have been reported to theoretically improve semen parameters in male infertility, a standard method has not been established. The authors examined whether tranilast, a mast cell blocker, improves fertility and/or semen parameters in severe oligozoospermia. Seventeen patients with a sperm density of less than 10 x 10(6) sperm/mL and their fertile partners were enrolled in this study. Patients were prescribed tranilast 300 mg/day for at least 12 weeks. Semen and blood samples were collected before and after the prescription of tranilast for 12 weeks. Semen parameters, serum gonadotropins, luteinizing hormone, follicle-stimulating hormone, serum testosterone, and testicular size were evaluated. One patient complained of mild drowsiness during treatment. The sperm count was significantly increased after administration of tranilast in 7 patients (41.1%), although sperm motility was not altered. Semen volume and normal morphology were also unaltered. Three pregnancies were achieved. Endocrine profile and testicular size were unchanged. Tranilast, a mast cell blocker, is clinically useful for the treatment of severe idiopathic oligozoospermic men.

Human testicular mast cells contain tryptase: increased mast cell number and altered distribution in the testes of infertile men

OBJECTIVE

To determine whether human testicular mast cells contain the potent fibroblast growth factor tryptase and to examine changes in mast cell morphology and intratesticular distribution in testes with normal spermatogenesis versus abnormal spermatogenesis.

DESIGN

Retrospective evaluation of testicular biopsies with the use of immunohistochemistry, morphometry, and electron microscopy.

SETTING

University research and clinical institutes.

PATIENT(S)

Infertile men (total of 24) with severe hypospermatogenesis, germ cell arrest syndrome, or Sertoli cell only syndrome, and men without pathologies.

INTERVENTION(S)

Diagnostic testicular biopsy.

MAIN OUTCOME MEASURE(S)

Location, number, and distribution of testicular mast cells.

RESULT(S)

All groups showed tryptase-positive mast cells. In specimens with normal spermatogenesis, mast cells were round and located mainly in the interstitial spaces close to Leydig cells. In germ cell arrest syndrome, a 2-fold increase was evident, and in Sertoli cell only syndrome, a >3-fold increase of tryptase-immunoreactive mast cells became evident. Moreover, there was a statistically significant shift of the cells from the interstitium to the tubular walls in Sertoli cell only syndrome and germ cell arrest syndrome. Mast cells in specimens of Sertoli cell only syndrome and germ cell arrest syndrome were heterogeneous, with rounded or elongated shapes and signs of degranulation. The thickness of the tubular walls was doubled in specimens of germ cell arrest syndrome and Sertoli cell only syndrome in comparison with normal specimens, and this increase was positively correlated with the number of mast cells in these patients.

CONCLUSION(S)

Our results suggest that mast cell products, including the potent fibroblast growth factor tryptase, are involved in the thickening of the tubular wall and other changes in infertile testes.

The use of ebastine, a mast cell blocker, for treatment of oligozoospermia

The effect of mast cell blocker (ebastine) on semen quality was evaluated in 15 idiopathic oligozoospermic males. Ten milligrams/day of ebastine was administered orally for 3 months. Nine cases (66.7%) showed definite improvement in the semen quality. The wives of 3 patients (20%) became pregnant within 6 months of the initial treatment. It would appear that mast cell blocker (ebastine) significantly improves semen quality in men with idiopathic oligozoospermia.

New treatment of idiopathic severe oligozoospermia with mast cell blocker: results of a single-blind study

OBJECTIVE

To determine whether mast cell blocker (tranilast) improves fertility and/or semen parameters in severe oligozoospermia.

DESIGN

Placebo-controlled single-blind clinical study.

SETTING

Nagoya University Hospital Andrology Clinic, Nagoya, Japan.

PATIENTS

Fifty men with sperm density < 5 x 10(6) sperm/mL, normal serum gonadotropins, and T, and a fertile partner were enrolled in this study.

INTERVENTIONS

Patients were prescribed randomly 300 mg/d tranilast or a placebo, three tablets per day, for 3 months. Semen and blood samples were collected before and after therapy. Semen parameters, serum gonadotropins, T, and PRL were evaluated before and after therapy.

RESULTS

The pregnancy rate (PR) in the mast cell blocker group was 28.6% compared with 0% in the placebo group. There was a statistical difference in the PR between groups. The mast cell blocker group had significantly higher levels of sperm density, sperm motility, and total motile sperm count. There were no differences between the mast cell blocker and placebo groups in seminal volume and normal sperm morphology.

CONCLUSIONS

The authors conclude that mast cell blocker is clinically useful for the treatment of idiopathic severe oligozoospermic men.

Guidelines for drug treatment of male infertility

The prerequisite for rational therapy of male fertility disorders is an exact diagnosis. While the possibilities of influencing disturbances of spermiogenesis are limited, male adnexal diseases can be successfully treated in many cases. Drugs for the treatment of fertility disorders must be applied with this in mind, and empiric therapy is often performed in addition to causal treatment which, however, may be quite rationally determined. The therapeutic spectrum in andrology includes antibiotic and antiphlogistic agents, mast cell blockers, zinc, vitamins, and immunosuppressive drugs (corticosteroids). These agents are used for the treatment of inflammatory diseases of the testes and the accessory glands or for suppression of antispermatozoal antibodies. Hormonal disturbances are infrequently encountered by the andrologist, but they can be treated, with proven efficacy, with gonadotrophins, gonadotrophin-releasing hormone (GnRH) or androgens. In certain cases that are not hormonally related, the use of antiestrogens (clomifene, tamoxifen) as stimulating agents may be successful. Furthermore, tissue hormone releasing proteases (kallikrein) can be used both therapeutically (especially in motility disturbances that are not due to structural flagellar defects) and diagnostically (in order to distinguish between inflammatory and noninflammatory testicular damage). Anticholinergics and alpha-sympathomimetics are applied to ameliorate ejaculation or emission failure. In addition to a review of these treatment forms, the development of new concepts, e.g. angiotensin converting enzyme (ACE) inhibitors, is discussed.

Mast cells in the testis, epididymis and accessory glands of the rat: effects of neonatal steroid treatment

Mast cells in the testis of control adult rats were found almost exclusively around subcapsular blood vessels. Discrete mast cells were distributed throughout the stroma of the epididymis and sex accessory glands. In neonatally estrogen-treated rats, a greater number of mast cells was present in the testicular interstitium, whereas no significant increase in the number of mast cells per square millimeter of stroma was found for the epididymis and sex accessory glands, despite stromal proliferation. On the other hand, androgen-treated rats did not have increased mast cell numbers in any organ. These results indicate that the increase in mast cell numbers was estrogen-dependent, specifically related to the testis and did not seem to be a consequence of the increase in the connective interstitial tissue.