Unexpected effect of testosterone in hypergonadotropic hypogonadism and nodular Leydig cell hiperplasia. Report of one case / Efecto inesperado de la testosterona en un hipogonadismo hipergonadotrófico e hiperplasia de las células de Leydig. Informe de un caso

ABSTRACT We report a 27 -year-old male referred because of hypergonadotropic hypogonadism with low testosterone and azoospermia. At 23 years of age, he underwent an excision of a hypoechoic 0.7 cm nodule of the left testicle. The pathological diagnosis was a Leydig cell tumor. In the right testicle, there were three nodules at ultrasound, the biggest measuring 0.6 cm. Four years later, the nodules in the right testicle were still present and the larger nodule was excised. The biopsy showed tubules with only Sertoli cells in the perinodular zone. Diffuse and nodular hyperplasia of the Leydig cells was found in the interstitium. The pathological diagnosis was Sertoli syndrome with severe hyperplasia of the Leydig cells. With testosterone therapy, LH decreased, and the nodules disappeared. Thereafter, upon interrupting therapy, LH increased, and the nodules reappeared in two occasions. Resuming testosterone treatment, the nodules disappeared again, suggesting a Leydig cell hyperplasia dependent on chronic LH stimulation.

Presentamos un varón de 27 años referido por hipogonadismo hipergonadotrófico con testosterona baja y azoospermia. El paciente tenía el antecedente de un nódulo sólido hipoecogénico de 0,7 cm en el testículo izquierdo, extirpado los 23 años de edad en el año 2002 y diagnosticado patológicamente como tumor de células de Leydig. En ese año se encontraron tres nódulos en el testículo derecho por ultrasonografía, el mayor de 0,6 cm. Cuatro años después, en 2007, los micronódulos del testículo derecho seguían presentes. El mayor de ellos fue extirpado. En la biopsia, había túbulos con solo células de Sertoli en la zona perinodular. En el intersticio había hiperplasia difusa y nodular de las células de Leydig. El diagnóstico patológico fue un síndrome de Sertoli con severa hiperplasia de células de Leydig. La terapia con testosterona disminuyó la LH y los nódulos inesperadamente desaparecieron. En dos ocasiones, al interrumpir esta terapia, la LH aumentó y los nódulos reaparecieron. Este proceso revirtió nuevamente con el uso de testosterona, sugiriendo una hiperplasia de células de Leydig dependiente del estímulo crónico de LH.

Unexpected effect of testosterone in hypergonadotropic hypogonadism and nodular Leydig cell hiperplasia. Report of one case.

We report a 27 -year-old male referred because of hypergonadotropic hypogonadism with low testosterone and azoospermia. At 23 years of age, he underwent an excision of a hypoechoic 0.7 cm nodule of the left testicle. The pathological diagnosis was a Leydig cell tumor. In the right testicle, there were three nodules at ultrasound, the biggest measuring 0.6 cm. Four years later, the nodules in the right testicle were still present and the larger nodule was excised. The biopsy showed tubules with only Sertoli cells in the perinodular zone. Diffuse and nodular hyperplasia of the Leydig cells was found in the interstitium. The pathological diagnosis was Sertoli syndrome with severe hyperplasia of the Leydig cells. With testosterone therapy, LH decreased, and the nodules disappeared. Thereafter, upon interrupting therapy, LH increased, and the nodules reappeared in two occasions. Resuming testosterone treatment, the nodules disappeared again, suggesting a Leydig cell hyperplasia dependent on chronic LH stimulation.

Morphological damage in Sertoli, myoid and interstitial cells in a mouse model of mucopolysaccharidosis type I (MPS I).

Mucopolysaccharidosis type I (MPS I) is a lysosomal storage disease caused by a mutation in the IDUA gene, which codes α-L-iduronidase (IDUA), a lysosomal hydrolase that degrades two glycosaminoglycans (GAGs): heparan sulfate (HS) and dermatan sulfate (DS). GAGs are macromolecules found mainly in the extracellular matrix and have important signaling and structural roles which are essential to the maintenance of cell and tissue physiology. Nondegraded GAGs accumulate in various cell types, which characterizes MPS I as a multisystemic progressive disease. Many tissues and vital organs have been described in MPS I models, but there is a lack of studies focused on their effects on the reproductive tract. Our previous studies indicated lower sperm production and morphological damage in the epididymis and accessory glands in male MPS I mice, despite their ability to copulate and to impregnate females. Our aim was to improve the testicular characterization of the MPS I model, with a specific focus on ultrastructural observation of the different cell types that compose the seminiferous tubules and interstitium. We investigated the testicular morphology of 6-month-old male C57BL/6 wild-type (Idua+/+) and MPS I (Idua-/-) mice. We found vacuolated cells widely present in the interstitium and important signs of damage in myoid, Sertoli and Leydig cells. In the cytoplasmic region of Sertoli cells, we found an increased number of vesicles with substrates under digestion and a decreased number of electron-dense vesicles similar to lysosomes, suggesting an impaired flux of substrate degradation. Conclusions: Idua exerts an important role in the morphological maintenance of the seminiferous tubules and the testicular interstitium, which may influence the quality of spermatogenesis, having a greater effect with the progression of the disease.

Relevance of angiogenesis in autoimmune testis inflammation.

Experimental autoimmune orchitis (EAO) is a useful model to study organ-specific autoimmunity and chronic testicular inflammation. This model reflects testicular pathological changes reported in immunological infertility in men. Progression of EAO in rodents is associated with a significantly increased percentage of testicular endothelial cells and interstitial testicular blood vessels, indicating an ongoing angiogenic process. Vascular endothelial growth factor A (VEGFA), the main regulator of physiological and pathological angiogenesis, can stimulate endothelial cell proliferation, chemotaxis and vascular permeability. The aim of this study was to explore the role of VEGFA in the pathogenesis of testicular inflammation. Our results found VEGFA expression in Leydig cells, endothelial cells and macrophages in testis of rats with autoimmune orchitis. VEGFA level was significantly higher in testicular fluid and serum of rats at the end of the immunization period, preceding testicular damage. VEGF receptor (VEGFR) 1 is expressed mainly in testicular endothelial cells, whereas VEGFR2 was detected in germ cells and vascular smooth muscle cells. Both receptors were expressed in testicular interstitial cells. VEGFR2 increased after the immunization period in the testicular interstitium and VEGFR1 was downregulated in EAO testis. In-vivo-specific VEGFA inhibition by Bevacizumab prevented the increase in blood vessel number and reduced EAO incidence and severity. Our results unveil relevance of VEGFA-VEGFR axis during orchitis development, suggesting that VEGFA might be an early marker of testicular inflammation and Bevacizumab a therapeutic tool for treatment of testicular inflammation associated with subfertility and infertility.

Hypothyroidism induced by postnatal PTU (6-n-propyl-2-thiouracil) treatment decreases Sertoli cell number and spermatogenic efficiency in sexually mature pigs.

Studies with 6-n-propyl-2-thiouracil (PTU) in laboratory rodents have shown that transient neonatal hypothyroidism leads to increased Sertoli cell (SC) number, testis size and sperm production. However, scarce and inconclusive data are available for farm animals. In the present study, Piau pigs received PTU in a gel capsule containing 8 mg/kg of body weight for 14 weeks starting from the first week of age, whereas control animals received only the vehicle. Blood samples were collected during the experimental period for hormonal evaluation in the serum. The animals were orchiectomized at adulthood and had their testes used for histomorphometric analysis. Indicating that the PTU concentration used was effective in promoting hypothyroidism, PTU-treated pigs showed a 30% lower body weight and reduced thyroxine levels (p < 0.05) during the treatment period. At adulthood, the body weight was similar in both groups but, surprisingly, PTU-treated pigs showed 30% lower testis weight (p < 0.05). In general, treated pigs presented increased follicle-stimulating hormone levels, whereas testosterone levels tended to be lower from 9 to 23 weeks of age. No significant differences were observed for estradiol, Leydig cell volume and number, tubular diameter, SC number per gram of testis, SC efficiency and meiotic index. However, seminiferous tubule occupancy, total tubular length, SC number per testis, and daily sperm production per testis and per gram of testis (DSP/g/T) were significantly lower (p < 0.05) in PTU-treated pigs. Therefore, in contrast to laboratory rodents, our results showed that SC proliferation and DSP/g/T (spermatogenic efficiency) in Piau pigs is diminished by postnatal PTU treatment.

Pfaffia glomerata hydroalcoholic extract stimulates penile tissue in adult Swiss mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Roots of Pfaffia glomerata are used in traditional medicine as aphrodisiacs and sexual stimulants. AIM OF THE STUDY: The aim of this study was to evaluate the action of the hydroalcoholic extract from the roots of Pfaffia glomerata on the Leydig cells, cavernous bodies and other penile constituents, as well as on serum testosterone and 17ß-estradiol levels of adult mice. MATERIALS AND METHODS: Mature male Swiss mice were divided into 6 groups: control (water), sildenafil citrate, 3 groups receiving daily doses of P. glomerata extract (100, 200 and 400 mg/kg) and one group receiving intermittent doses of P. glomerata (200 mg/kg/3-3d). RESULTS: The proportions of blood vessels, lymphatic space and estradiol levels were increased. On the other hand, reduction of testosterone levels due to Leydig cells death was observed. As for penile parameters, volumetric proportions of cavernous bodies, collagen and nitric oxide were increased, while smooth muscle content was decreased. CONCLUSIONS: Despite that the long term intake of P. glomerata extract was related to a stimulant action, reduction on Leydig cell viability induced decreased testosterone production.

Numeric and volumetric changes in Leydig cells during aging of rats.

PURPOSE: To analyze the effects of aging in rats on the nuclear volume, cytoplasmic volume, and total volume of Leydig cells, as well as their number. METHODS: Seventy-two Wistar rats were divided into six subgroups of 12 rats, which underwent right orchiectomy at 3, 6, 9, 12, 18, and 24 months of age. The weight and volume of the resected testicles were assessed. A stereological study of Leydig cells was conducted, which included measurements of cell number and nuclear, cytoplasmic, and total cell volumes. RESULTS: The weight and volume of the resected testicles showed reductions with age. Only the subgroup composed of 24-month old rats showed a decrease in the nuclear volume of Leydig cells. Significant reductions in the cytoplasmic volume and total volume of Leydig cells were observed in 18- and 24-month old rats. The number of Leydig cells did not vary significantly with age. CONCLUSIONS: Aging in rats resulted in reduction of the nuclear, cytoplasmic, and total cell volumes of Leydig cells. There was no change in the total number of these cells during aging.

Numeric and volumetric changes in Leydig cells during aging of rats

Abstract Purpose: To analyze the effects of aging in rats on the nuclear volume, cytoplasmic volume, and total volume of Leydig cells, as well as their number. Methods: Seventy-two Wistar rats were divided into six subgroups of 12 rats, which underwent right orchiectomy at 3, 6, 9, 12, 18, and 24 months of age. The weight and volume of the resected testicles were assessed. A stereological study of Leydig cells was conducted, which included measurements of cell number and nuclear, cytoplasmic, and total cell volumes. Results: The weight and volume of the resected testicles showed reductions with age. Only the subgroup composed of 24-month old rats showed a decrease in the nuclear volume of Leydig cells. Significant reductions in the cytoplasmic volume and total volume of Leydig cells were observed in 18- and 24-month old rats. The number of Leydig cells did not vary significantly with age. Conclusions: Aging in rats resulted in reduction of the nuclear, cytoplasmic, and total cell volumes of Leydig cells. There was no change in the total number of these cells during aging.

A high-fat diet fed during different periods of life impairs steroidogenesis of rat Leydig cells.

This study evaluated the impact of a high-fat diet (HFD) during different stages of rat life, associated or not with maternal obesity, on the content of sex steroid hormones and morphophysiology of Leydig cells. The following periods of development were examined: gestation (O1), gestation and lactation (O2), from weaning to adulthood (O3), from lactation to adulthood (O4), gestation to adulthood (O5), and after sexual maturation (O6). The HFD contained 20% unsaturated fat, whereas the control diet had 4% fat. Maternal obesity was induced by feeding HFD 15 weeks before mating. All HFD groups presented increased body weight, hyperinsulinemia and reduced insulin sensitivity. Except for O1, all HFD groups exhibited a higher adiposity index, hyperleptinemia, reduced testosterone and estradiol testicular levels, and decreased testicular 17ß-HSD enzyme . Morphometrical analyses indicated atrophy of Leydig cells in the O2 group. Myelin vesicles were observed in the mitochondrial matrix of Leydig cells in O3, O4, O5 and O6, and autophagosomes containing mitochondria were found in O5 and O6. In conclusion, HFD feeding, before or after sexual maturation, reduces the functional capacity of rat Leydig cells. Maternal obesity associated with HFD during pregnancy/lactation prejudices Leydig cell steroidogenesis and induces its atrophy in adulthood, even if it is replaced by a conventional diet at later stages of life. Regardless of the life period of exposure to HFD, deregulation of leptin is the main factor related to steroidogenic impairment of Leydig cells, and, in groups exposed for longer periods (O3, O4, O5 and O6), this is worsened by structural damage and mitochondrial degeneration of these cells.

Alterations in oxidative, inflammatory and apoptotic events in short-lived and long-lived mice testes.

Aged testes undergo profound histological and morphological alterations leading to a reduced functionality. Here, we investigated whether variations in longevity affect the development of local inflammatory processes, the oxidative state and the occurrence of apoptotic events in the testis. To this aim, well-established mouse models with delayed (growth hormone releasing hormone-knockout and Ames dwarf mice) or accelerated (growth hormone-transgenic mice) aging were used. We hereby show that the testes of short-lived mice show a significant increase in cyclooxygenase 2 expression, PGD2 production, lipid peroxidation, antioxidant enzymes expression, local macrophages and TUNEL-positive germ cells numbers, and the levels of both pro-caspase-3 and cleaved caspase-3. In contrast, although the expression of antioxidant enzymes remained unchanged in testes of long-lived mice, the remainder of the parameters assessed showed a significant reduction. This study provides novel evidence that longevity confers anti-inflammatory, anti-oxidant and anti-apoptotic capacities to the adult testis. Oppositely, short-lived mice suffer testicular inflammatory, oxidative and apoptotic processes.

Inhibition of NOS-NO System Prevents Autoimmune Orchitis Development in Rats: Relevance of NO Released by Testicular Macrophages in Germ Cell Apoptosis and Testosterone Secretion.

BACKGROUND: Although the testis is considered an immunoprivileged organ it can orchestrate immune responses against pathological insults such as infection and trauma. Experimental autoimmune orchitis (EAO) is a model of chronic inflammation whose main histopathological features it shares with human orchitis. In EAO an increased number of macrophages infiltrate the interstitium concomitantly with progressive germ cell degeneration and impaired steroidogenesis. Up-regulation of nitric oxide (NO)-NO synthase (NOS) system occurs, macrophages being the main producers of NO. OBJECTIVE: The aim of our study was to evaluate the role of NO-NOS system in orchitis development and determine the involvement of NO released by testicular macrophages on germ cell apoptosis and testosterone secretion. METHOD AND RESULTS: EAO was induced in rats by immunization with testicular homogenate and adjuvants (E group) and a group of untreated normal rats (N) was also studied. Blockage of NOS by i.p. injection of E rats with a competitive inhibitor of NOS, L-NAME (8mg/kg), significantly reduced the incidence and severity of orchitis and lowered testicular nitrite content. L-NAME reduced germ cell apoptosis and restored intratesticular testosterone levels, without variations in serum LH. Co-culture of N testicular fragments with testicular macrophages obtained from EAO rats significantly increased germ cell apoptosis and testosterone secretion, whereas addition of L-NAME lowered both effects and reduced nitrite content. Incubation of testicular fragments from N rats with a NO donor DETA-NOnoate (DETA-NO) induced germ cell apoptosis through external and internal apoptotic pathways, an effect prevented by N-acetyl-L-cysteine (NAC). DETA-NO inhibited testosterone released from Leydig cells, whereas NAC (from 2.5 to 15 mM) did not prevent this effect. CONCLUSIONS: We demonstrated that NO-NOS system is involved in the impairment of testicular function in orchitis. NO secreted mainly by testicular macrophages could promote oxidative stress inducing ST damage and interfering in Leydig cell function.

Environmentally Realistic Doses of Cadmium as a Possible Etiologic Agent for Idiopathic Pathologies.

Cadmium is a heavy metal of increasing environmental concern that has long been associated to several human pathological processes. Recent population surveys have correlated cadmium non-occupational exposure to widespread idiopathic pathologies. Food and tobacco are reported to be the main exposure sources of cadmium to the general population, as phosphate fertilizers are rich in such a metal, thus contaminating the crops. Although its mechanisms of toxicity are not a consensus in the literature, it is well established that reactive oxygen species play a key role in this process, leading to the oxidation of several biological molecules. We have therefore assessed whether three environmentally realistic doses of cadmium alter the oxidative status of Wistar rat testis and eventually result in histological damages. Our results show that even the lowest environmental dose of cadmium was able to disturb the endogenous antioxidant system in Wistar testis, although an increase in lipid peroxidation was observed only within the group exposed to the highest environmental dose. Despite that no remarkable morphological changes were observed in any group, significant alterations in blood vessel lumen were reported for some cadmium-exposed animals, suggesting that endothelium is one of the primary targets involved in cadmium toxicity.

The prepubertal testis: biomarkers and functions.

PURPOSE OF REVIEW: Biomarkers of prepubertal testicular function have become widely available only in recent years. The aim of this review is to update the knowledge on key biomarkers used to assess hypogonadism in boys. RECENT FINDINGS: Sertoli cells are the most representative cells of the prepubertal testis. Anti-Müllerian hormone and inhibin B are essential biomarkers of Sertoli cell function. Also, INSL3 arises as an additional marker of Leydig cell dysfunction. SUMMARY: The widespread use of these biomarkers has enhanced our knowledge on the pathophysiology and diagnosis of prepubertal male hypogonadism. Beyond their well known germ-cell toxicity, oncologic treatments may also affect Sertoli cell function. Pathophysiology is not the same in all aneuploidies leading to infertility: while hypogonadism is not evident until mid-puberty in Klinefelter syndrome, it is established in early infancy in Down syndrome. In Noonan syndrome, the occurrence of primary hypogonadism depends on the existence of cryptorchidism, and Prader-Willi syndrome may present with either primary or combined forms of hypogonadism. Prepubertal testicular markers have also provided insights into the effects of environmental disruptors on gonadal function from early life, and helped dissipate concerns about testicular function in boys born preterm or small for gestational age or conceived by assisted reproductive technique procedures.

[Leprosy and the testis]. / La lepra y el testículo.

INTRODUCTION: Damage of testicles is frequent in lepromatous leprosy and worsened by the presence of erythema nodosum leprosum. Objective. A patient is presented who developed lepromatous leprosy and erythema nodosum leprosum with major testicular compromise. MATERIAL AND METHODS: The 28-year-old male patient had lepromatous leprosy since age 22. During a polychemotherapy treatment for the lepromatous leprosy, he presented chronic erythema nodosum leprosum that affected both testicles; he did not respond to the conventional treatment. A left orchidectomy was performed to treat the persistent pain. RESULTS: The extracted testis evidenced the following: tubular atrophy, extensive fibrosis, cumulus of foamy macrophages without rods, focal Leydig cell hyperplasia, linfocitary and granulomatous arteritis and endarteritis of small and medium size vessels. These changes were also observed in the epididymis. Two years after the polychemoterapy and the orchidectomy, the patient exhibited azoospermy, normal total testosterone, slightly diminished free testosterone and elevated levels of luteinizing hormone and follicle-stimulating hormone. No loss of libido or sexual activity was reported. General concepts of erythema nodosum leprosum were reviewed, as well as the pathologic changes produced by leprosy in the testis. CONCLUSION: Lepromatous leprosy may lead to hypogonadism. This condition is recommended for inclusion in leprosy diagnostic programs in order to detect and treat the consequences of the possible hypogonadism.

La lepra y el testículo / Leprosy and the testis

Introducción. La afección testicular es frecuente en la lepra lepromatosa, daño que se incrementa cuando cursa con eritema nudoso leproso. Objetivo. Presentar un paciente con lepra lepromatosa y eritema nudoso leproso con grave compromiso testicular. Materiales y métodos. Se estudió un hombre de 28 años con lepra lepromatosa desde los 22, que durante la poliquimioterapia para la lepra presentó eritema nudoso leproso crónico que afectó ambos testículos y no respondió al manejo convencional. El dolor persistente obligó a practicar orquidectomía izquierda. Resultados. Este testículo presentaba atrofia tubular y fibrosis notorias, conglomerados de macrófagos espumosos, sin bacilos, hiperplasia focal de células de Leydig, endarteritis y arteritis linfocitaria y granulomatosa de vasos pequeños y medianos; estos cambios también estaban presentes en el epidídimo. Un estudio llevado a cabo dos años después de terminar su tratamiento y de la orquidectomía izquierda, demostró azoospermia, testosterona total normal, testosterona libre discretamente disminuida y hormonas lutropina (luteinizante) y folitropina (estimulante del folículo) elevadas. No había disminución de la libido ni de su actividad sexual. Se revisaron los conceptos generales sobre el eritema nudoso leproso y las alteraciones que la lepra produce en el testículo. Conclusión. La lepra lepromatosa puede conducir a hipogonadismo. Los programas de lepra deben contemplar esta complicación para corregir y evitar sus secuelas.

Introduction. Damage of testicles is frequent in lepromatous leprosy and worsened by the presence of erythema nodosum leprosum. Objective. A patient is presented who developed lepromatous leprosy and erythema nodosum leprosum with major testicular compromise. Material and methods. The 28-year-old male patient had lepromatous leprosy since age 22. During a polychemotherapy treatment for the lepromatous leprosy, he presented chronic erythema nodosum leprosum that affected both testicles; he did not respond to the conventional treatment. A left orchidectomy was performed to treat the persistent pain. Results. The extracted testis evidenced the following: tubular atrophy, extensive fibrosis, cumulus of foamy macrophages without rods, focal Leydig cell hyperplasia, linfocitary and granulomatous arteritis and endarteritis of small and medium size vessels. These changes were also observed in the epididymis. Two years after the polychemoterapy and the orchidectomy, the patient exhibited azoospermy, normal total testosterone, slightly diminished free testosterone and elevated levels of luteinizing hormone and follicle-stimulating hormone. No loss of libido or sexual activity was reported. General concepts of erythema nodosum leprosum were reviewed, as well as the pathologic changes produced by leprosy in the testis. Conclusion. Lepromatous leprosy may lead to hypogonadism. This condition is recommended for inclusion in leprosy diagnostic programs in order to detect and treat the consequences of the possible hypogonadism.

Expression of the TGF-beta1 system in human testicular pathologies.

BACKGROUND: In non-obstructive azoospermia, histological patterns of Sertoli cell-only Syndrome (SCO) and hypospermatogenesis (H) are commonly found. In these pathologies, Leydig cell hyperplasia (LCH) is detected in some patients. Since TGF-ß1 is involved in cellular proliferation/development, the aim of this work was to analyze the expression of TGF-ß1, its receptors TGFBRII, TGFBRI (ALK-1 and ALK-5), and the co-receptor endoglin in human biopsies from patients with idiopathic infertility. METHODS: Specific immunostaining of TGF-ß1, its receptors TGFBRII, TGFBRI (ALK-1 and ALK-5), co-receptor endoglin and Smads proteins, were carried out in testicular biopsies from normal and infertile men with SCO or H. Gene expression of TGF-ß1 system were made in biopsies from infertile patients with semi-quantitative and quantitative PCR. RESULTS: Immunohistochemical studies revealed that TGF-ß1 and its specific receptors are present in Leydig cells in biopsies from normal tissue or patients with SCO or H with or without LCH. Smad proteins, which are involved in TGF-ß1 signaling, are also detected in both their phosphorylated (activated) and dephosphorylated form in all samples TGF-ß1, ALK-1 and endoglin gene expression are stronger in human biopsies with LCH than in those with SCO or H. Neither TGFBRII nor ALK-5 gene expression showed significant differences between pathologies. A significant correlation between ALK-1 and endoglin expression was observed. CONCLUSIONS: In conclusion, the high levels of mRNA and protein expression of the TGF-ß1 system in patients with LCH, particularly ALK1 and its correlation with endoglin, suggest that these proteins acting in concert might be, at least in part, committed actors in the Leydig cell hyperplasia.

Origin and evolution of somatic cell testicular tumours in transgenic mice.

Transgenic mice bearing a construct in which the expression of the SV40 oncogene is directed by the AMH promoter (AT mice) develop testicular tumours in adult life. We aimed to study early steps of tumour development and characterize tumours at different ages by histological, morphometric, and immunohistochemical techniques. One- to 3-month-old AT mice depicted multifocal Leydig cell hyperplasia. The testicular volume occupied by interstitial tissue was significantly higher in 3-month-old AT mice in comparison with littermate controls. Between 5 1/2 and 7 months, microscopic interstitial tumours developed that progressively evolved to form large confluent areas of high mitotic index in 7- to 14-month-old AT mice. Tumour cells had the characteristics and histoarchitecture of Leydig cells, or formed solid cord-like structures reminiscent of those seen in Sertoli cell tumours. Hyperplastic areas and tumours diffusely expressed 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in Leydig cell areas. AMH expression was negative in Leydig cell conglomerates and tumours and variable in cord-like tumours. The SV40 T antigen and markers of cell proliferation (PCNA) were intensely positive in hyperplastic cells and tumours. Control mice of similar ages showed neither hyperplasia nor tumours, and SV40 T expression was always negative. In conclusion, transgenic mice develop large testicular tumours that are preceded by interstitial hyperplasia and microtumours. The histological and immunohistochemical phenotype of tumours (Leydig and Sertoli cell differentiation, positive 3beta-HSD, and variable AMH) suggests a mixed differentiation of somatic cells of the specialized gonadal stroma. The finding that an oncogene directed by a promoter specifically active in fetal Sertoli cells has given rise to testicular tumours of mixed differentiation is compatible with a common origin of Leydig and Sertoli cells from the specific stroma of the gonadal ridge, as supported by double labelling experiments in fetal mice showing co-localization of the transgene with Sertoli and Leydig cell markers.

TGF-beta1 system in Leydig cells. Part II: TGF-beta1 and progesterone, through Smad1/5, are involved in the hyperplasia/hypertrophy of Leydig cells.

Several reports indicate that transforming growth factor beta1 (TGF-beta1) participates in the regulation of cell cycle progression. In this work, we analyzed the in vitro effect of TGF-beta1 on Leydig cell proliferation markers and the in vivo effect of this cytokine in Leydig cell hyperplasia/hypertrophy. The in vitro effect of TGF-beta1 (1 ng/ml) plus progesterone (10(-6) M) on purified Leydig cells from 3 week-old mice increased the immunocytochemically detected PCNA and stimulated the phosphorylation of Smad 1/5. Progesterone (10(-6) M) in the presence or absence of TGF-beta1 diminished the ratio Bax/Bcl-2. Morphometric testicular studies of mice treated with progesterone (s.c.) plus TGF-beta1 (intratesticular), showed an increase in interstitial volume and a decrease in tubular volume. Furthermore, the cytoplasmic volume of Leydig cells showed an increment in this experimental group with a diminution in nuclear volume. Thus, it turned out that the administration of progesterone and TGF-beta1 augmented the volume of Leydig cells. These results indicate a clear effect of TGF-beta1 in the hypertrophy/hyperplasia of Leydig cells.

Cyclooxygenase-2 in testes of infertile men: evidence for the induction of prostaglandin synthesis by interleukin-1ß.

As we previously reported, testes of men suffering from hypospermatogenesis and germ cell arrest or Sertoli cell-only syndrome show a major increase in the number of macrophages expressing interleukin-1ß (IL-1ß) and abundant expression of cyclooxygenase-2 (COX-2), the inducible isoform of the key enzyme in the biosynthesis of prostaglandins (PGs), in Leydig cells. In the present study we report [1] a positive correlation between IL-1ß levels and COX-2 expression in testes of infertile patients, [2] the induction of COX-2 by IL-1ß in mouse Leydig cells (TM3) and human macrophages (THP-1), and therefore [3] evidence for an IL-1ß-dependent induction of testicular inflammatory states.