Treatment of cryptorchidism with human chorionic gonadotropin or gonadotropin releasing hormone. A double-blind controlled study of 243 boys

We have conducted a modified double-blind study on the effect of human chorionic gonadotropin (hCG), gonadotropin releasing hormone (GnRH) and placebo on bilateral and unilateral maldescended testes. One hundred and fifty-five boys with bilateral and 88 boys with unilateral cryptorchidism fulfilled the inclusion criteria and completed the treatment protocol. The boys were between 1 and 13 years of age. hCG was administered as intramuscular injections twice weekly for 3 weeks. GnRH and placebo were given intranasally. hCG was superior to GnRH and placebo in the treatment of bilateral maldescended testes (p = 0.0009). Both testes descended in 25% of the boys following treatment with hCG, and improvement in the position of the testes was obtained in a further 25% of the cases. hCG administration resulted in complete testicular descent in 14% of boys with unilateral cryptorchidism compared with 3 and 0% after placebo and GnRH, respectively (p = 0.07). The testis had moved to a more distal position in 46% of the boys treated with hCG. There was no significant difference between the treatment groups with regard to age or initial position of the testes. We conclude that a success rate of 25% justifies the use of hCG in the treatment of maldescended testes, whereas the study did not support a general use of GnRH administered intranasally.     

Characteristics of cryptic/ectopic and contralateral scrotal testes in dogs between 1 and 2 years of age

Testicular malposition represents a common developmental genital defect in dogs and can affect one or both testes. In both humans and dogs, unilateral cryptorchism is more frequently detected and thought to be the expression of a genetic abnormality affecting both the undescended and scrotal testis. In the dog, there is evidence of degenerative processes affecting the maldescended testis. However, the histologic and functional changes that occur in the scrotal testis of unilateral cryptorchid or ectopic individuals remain a source of debate. Because the bilateral surgical removal of the testes leads to some undesirable side effects, the aim of this study was to evaluate the necessity for performing bilateral orchiectomy in young unilateral cryptorchid dogs. A morphologic study of both cryptic/ectopic and scrotal testes in young dogs affected by unilateral testicular maldescent was therefore conducted. The study was conducted on 10 dogs aged 1 to 2 yr and affected by unilateral testicular maldescent. We found that, in young dogs, even if no neoplastic lesions were observed, morphologic abnormalities are detectable between 1 and 2 yr of age in the maldescended testes with severity dependent on testicular position. In contrast, in the scrotal testes, the histologic and immunohistochemical exam failed to find signs of incorrect development or morphologic abnormalities. The results seem to suggest that, though the early removal of the undescended testis is recommended, continuous monitoring of the scrotal testis for the life of the dog is preferable to removing it considering the undesirable side effects related to castration.     

Environmental effects on hormonal regulation of testicular descent

Regulation of testicular descent is hormonally regulated, but the reasons for maldescent remain unknown in most cases. The main regulatory hormones are Leydig cell-derived testosterone and insulin-like factor 3 (INSL3). Luteinizing hormone (LH) stimulates the secretion of these hormones, but the secretory responses to LH are different: INSL3 secretion increases slowly and may reflect the LH dependent differentiated status of Leydig cells, whereas testosterone response to LH is immediate. Testosterone contributes to the involution of the suspensory ligament and to the inguinoscrotal phase of the descent, while INSL3 acts mainly in transabdominal descent by stimulating the growth of the gubernaculum. INSL3 acts through a G-protein coupled receptor LGR8. In the absence of either INSL3 or LGR8 mice remain cryptorchid. In humans only few INSL3 mutations have been described, whereas LGR8 mutations may cause some cases of undescended testis. Similarly, androgen insensitivity or androgen deficiency can cause cryptorchidism. Estrogens have been shown to down regulate INSL3 and thereby cause maldescent. Thus, a reduced androgen–estrogen ratio may disturb testicular descent. Environmental effects changing the ratio can thereby influence cryptorchidism rate. Estrogens and anti-androgens cause cryptorchidism in experimental animals. In our cohort study we found higher LH/testosterone ratios in 3-month-old cryptorchid boys than in normal control boys, suggesting that cryptorchid testes are not cabable of normal hormone secretion without increased gonadotropin drive. This may be either the cause or consequence of cryptorchidism. Some phthalates act as anti-androgens and cause cryptorchidism in rodents. In our human material we found an association of a high phthalate exposure with a high LH/testosterone ratio. We hypothesize that an exposure to a mixture of chemicals with anti-androgenic or estrogenic properties (either their own activity or their effect on androgen–estrogen ratio) may be involved in cryptorchidism.     

Risk of testicular cancer in cohort of boys with cryptorchidism.

OBJECTIVE: To determine the risk of testicular cancer in relation to undescended testis and its treatment based on recorded details of the maldescent, treatment, and biopsy from case notes. DESIGN: Cohort study. SETTING: Hospital for Sick Children, Great Ormond Street, London. SUBJECTS: 1075 boys with cryptorchidism treated by orchidopexy or hormones at the hospital during 1951-64. MAIN OUTCOME MEASURES: Relative risk of testicular cancer in the cohort compared with men in the general population. RESULTS: 12 testicular cancers occurred in 11 of the patients during follow up to mid-1990 (relative risk of cancer in males with cryptorchidism = 7.5 (95% confidence interval 3.9 to 12.8)). The relative risk fell significantly beyond 15 years after orchidopexy but did not decrease with younger age at orchidopexy. Risk was significantly raised in testes that had had biopsy samples removed during orchidopexy (relative risk = 66.7 (23.9 to 143.3) compared with a testis in a man in the general population) and was significantly greater in these testes than in undescended testes that had not had biopsy samples taken at orchidopexy (6.7 (2.7 to 13.5)). No reasons for biopsy or distinguishing clinical aspects of the testes that had had biopsy samples taken and later developed malignancies were evident in the case notes. No histological abnormalities were evident at initial biopsy except in one testis that had features of dysgenesis. CONCLUSIONS: Biopsy seems to be a stronger risk factor for testicular cancer than any factor previously identified. The trauma of open biopsy may contribute substantially to risk of malignancy or the testes may have been selected for biopsy on the basis of clinical factors predictive of malignancy but not mentioned in the case notes.     

Hormonal therapy for the subfertility of cryptorchidism.

BACKGROUND: The subfertility of cryptorchidism correlates with severely reduced total germ cell counts in prepubertal testicular biopsies of undescended testes. Reduced total germ cell counts are associated with defects in the two prepubertal steps in maturation and proliferation in germ cells: first, the transformation of the fetal stem cell pool (gonocytes) into the adult stem cell pool (adult dark spermatogonia) at two to three months of age and, second, the transformation of adult dark spermatogonia into primary spermatocytes (meiosis) at 4-5 years. The defects in maturation are associated with blunting of the normal surges in gonadotropins and testosterone. Prepubertal treatment with gonadotropin-releasing hormones would theoretically trigger normal germ cell maturation and proliferation and thereby improve total germ cell counts and improve fertility. Prepubertal treatment of cryptorchidism with the GnRH analogue Buserelin has resulted in improved total germ cell counts and improved spermiograms. The purpose of this report is to describe the results of treatment of cryptorchidism with the GnRH analogue Naferelin. PATIENTS: Twelve boys with cryptorchidism, 6 unilateral and 6 bilateral, and severely reduced germ cell counts in testicular biopsies were treated with Naferelin following successful orchidopexy and bilateral testicular biopsies. Response of the total germ cell counts was assessed in follow-up bilateral biopsies within 5 months of completing the hormonal therapy. RESULTS: Eight of the 12 boys (5 of the 6 with unilateral and 3 of the 6 with bilateral cryptorchidism) showed improvement in the total germ cell counts in one or both testes. All 8 had a poor prognosis for fertility pretreatment and a good prognosis for fertility posttreatment. Of the 5 with unilateral cryptorchidism who improved, 2 showed improvement in both testes; and 3, only in the contralateral descended testes. All 3 of the boys with bilateral cryptorchidism who improved showed improvement in both testes. Testes with absence of germ cells and older patients tended to show no improvement. Of the 6 contralateral descended, 5 (83%) improved, and of the 18 undescended testes, 8 (44%) improved. CONCLUSIONS: In this preliminary study, Naferelin therapy appears to induce improvement in the total germ cell counts and the prognosis for future fertility in 75% of patients.     

Cryptorchidie et infertilité masculine

Cryptorchidism is one of the various forms of testicular maldescent. Cryptorchidism is still reported to have discrepant effects upon the exocrine function of the male gonade. Besides some new information about epidemiology and risck factors associated with cryptorchidism, data from the literature are reviewed concerning spermatogenesis, fatherhood and infertility in men with a history of cryptorchidism. The discrepancy of the results is such important that only prospective and multicentric studies involving various experts seem to be appropriate to approach the complex problems arising from the maldescended testis.     

Abnormal germ cell development in cryptorchidism.

BACKGROUND: Previous studies suggest that two fundamental, probably androgen-dependent, steps in maturation of germ cells normally occur in the prepubertal testis: the disappearance of gonocytes (the fetal stem cell pool) and the appearance of adult dark spermatogonia (the adult stem cell pool) at 2-3 months of age and the appearance of primary spermatocytes (the onset of meiosis) at 4-5 years. Previous studies of small series of cryptorchid boys suggest that both steps are defective in undescended testes and to a lesser degree in descended testes contralateral to unilaterally undescended testes. The purpose of this study is to confirm the previous findings of defective germ cell maturation in a large series of boys with unilateral undescended testes. PATIENTS: Seven hundred and sixty-seven boys with unilateral cryptorchidism who had orchidopexy and bilateral testicular biopsies between birth and 9 years of age were studied. MATERIALS AND METHODS: Total and differential germ cell counts were performed on semithin histologic sections of the biopsies. The results from the undescended and contralateral descended testes were compared using the Wilcoxon signed-rank test and the Wilcoxon-Whitney-Mann U test. RESULTS: Gonocytes failed to disappear and adult dark spermatogonia failed to appear in undescended testes under 1 year of age indicating a defect in the first step in maturation at 2-3 months resulting in failure to establish an adequate adult stem cell pool. Primary spermatocytes failed to appear in undescended testes and appeared in only 19% of contralateral descended testes at 4-5 years of age indicating a defect in the onset of meiosis. CONCLUSION: Unilaterally undescended testes fail to establish an adequate adult stem cell pool which normally occurs at 2-3 months of age and fail to establish adequate meiosis which normally occurs at 4-5 years of age. Similar but less severe changes are seen in the contralateral descended testes. Defects in the two pubertal steps in germ cell maturation are associated with reduced total germ cell counts.     

Erythropoietin may reduce the risk of germ cell loss in boys with cryptorchidism.

PURPOSE: In boys with cryptorchidism older than 2 years a testicular biopsy at time of orchiopexy shows lack of germ cells in 10-40% of the cases. The number of spermatogonia per tubule is prognostic for subsequent fertility potential. A biopsy without germ cells is associated with 33-100% risk of infertility. In order to increase the number of germ cells, and thereby the fertility potential, additional hormonal therapy has been attempted before surgery. In a study, small doses of the gonadotropin-releasing hormone analogue buserelin before orchiopexy caused higher values. Others have found that hormonal treatment with human chorionic gonadotropin or gonadotropin releasing hormone analogue may harm the germ cells in cryptorchidism. The aim of the study is to demonstrate that additional hormonal therapy with erythropoietin has a positive effect on the number of germ cells. MATERIALS AND METHODS: Erythropoietin (Eprex) 100 IU/kg were administered subcutaneously weekly for 3 months prior to surgery in two cryptorchid boys, 6 months old and 1 year 9 months old, respectively, with renal function impairment. RESULTS: The number of spermatogonia per tubular cross-section in testicular biopsies was unusually high in both erythropoietin- treated cryptorchid cases compared to the control material of biopsies from the undescended testes of 698 cryptorchid patients and compared to the normal values. CONCLUSION: There are several hypothetic mechanisms that can explain the elevated number of spermatogonia seen in our erythropoietin treated cryptorchid patients. Erythropoietin may have a positive effect on germ cell proliferation in cryptorchidism.     

The epidemiology of cryptorchidism. John Radcliffe Hospital Cryptorchidism Research Group

A total of 3,559 boys were examined for cryptorchidism over a 2-year period. At birth, 5.9% (210/3,534) had one or both testes undescended and at 3 months of age 1.61% (57/3,534) still had an undescended testis. These figures represent an increase in undescended testis of 40% at birth and 68% at 3 months when compared with figures collected in a similar study in the late 1950s. This increase in cryptorchidism still does not account for the increased number of orchiopexies being performed. Low birthweight was also found to be a risk factor for the presence of an undescended testis.     

Hormonal treatment for unilateral inguinal testis: comparison of four different treatments.

BACKGROUND: Hormonal treatment of cryptorchidism has been used since the 30s, but controversies persist on its efficacy. It is also unclear whether there are differences with the use of different hormonal trials. Aims: To evaluate the efficacy of four hormonal treatments on testicular descent in a homogeneous group of cryptorchid boys. PATIENTS: 155 patients (age 10-48 months) with unilateral inguinal palpable testis were studied. Methods: The patients were subdivided into four groups according to hormonal treatment: group 1 = hCG [500 IU/week (if the chronological age was <2 years) or 1,000 IU/week (if the chronological age was >2 years) for 6 weeks]; group 2 = hCG + hMG (hCG as in group 1 + hMG 75 IU/week for 6 weeks); group 3 = GnRH (1,200 microg/daily for 28 days); group 4 = GnRH + hCG (1,200 microg/daily for 28 days + 1,500 IU/week for 3 weeks, respectively). The results were evaluated at the end of the treatment period and 6 months later to exclude temporarily positive results. RESULTS: At the end of the hormonal therapy, scrotal testicular descent was present in 30 of 155 boys (success rate 19.3%). Seven testes relapsed during follow-up (23.3%). The long-term success rate was 14.8% (23/155 testes). No significant differences were observed in success rates as well as in relapse rates among the four groups. CONCLUSIONS: Hormonal therapy induced permanent testicular descent in a minority of young cryptorchid boys with inguinal palpable testis. Similar results were obtained with four different trials.     

Impaired gonadotrophin uptake in vivo by the cryptorchid rat testis

The specific testicular uptake in vivo of 125I-labelled hCG was compared in control adult rats and adult rats made bilaterally cryptorchid 5 weeks previously. Although a similar temporal pattern of uptake was observed in both groups, uptake of hCG by cryptorchid testes was reduced at all times after injection by up to 70%. The possible causes of this impairment were investigated. It could not be accounted for by differences in the rate of absorption or clearance of 125I-labelled hCG in the two groups. Therefore, because hCG-induced increase in the permeability of testicular capillaries is a crucial factor in determining hCG uptake by the testis, this change was compared in control and cryptorchid testes. Although hCG induced a characteristic increase in testicular capillary wall permeability in both groups, this change was temporally delayed in cryptorchid testes, and occurred after hCG values in the blood had fallen. Even when hCG had crossed the capillary wall into testicular interstitial fluid, its uptake into the testicular tissue was significantly lower in cryptorchid than in control testes. These changes probably account for the impairment of gonadotrophin uptake by the cryptorchid testis and have important implications with respect to the aetiology of Leydig cell changes in cryptorchidism.     

Cryptorchidism: aspects of fertility and neoplasms. A study including data of 1,335 consecutive boys who underwent testicular biopsy simultaneously with surgery for cryptorchidism.

PURPOSE: An attempt to make a rational strategy for treatment of cryptorchidism. MATERIALS AND METHODS: 1,335 cryptorchid boys with biopsy at surgery (1,638 specimens). We studied: frequency of no germ cells in biopsies from 698 patients <12 years at surgery; fertility potential of 140 patients who were now adults, and apperance of testicular neoplasia in all biopsies. RESULTS: Lack of germ cells appeared from 18 months. The frequency increased with increasing age. It appeared in 30% (61/202) bilateral, and 18% (88/496) unilateral cases. In men who had undergone bilateral or unilateral orchiopexy, respectively, there was normal sperm count in 19% (14/75) and 83% (54/65), and infertility was suspected in 56% (42/75) and 8% (5/65) (FE, p < 0.00005, p < 0.00005), respectively. The lowest, the mean, and the highest age-matched spermatogonia count per tubule at orchiopexy was associated with sperm count (Spearman test, p < 0.0001, p < 0.005, p < 0.05). Isolated, this was demonstrated for the 75 formerly bilateral (Spearman, p < 0.0001, p < 0.0001, p < 0.0001), but not the 65 formerly unilateral cases (Spearman, p = 1.0). No germ cells at orchiopexy was associated with suspected infertility. Risk was 78-100% in bilateral (dependent on one or both testes affected), and 33% in unilateral cryptorchidism. There was one invasive germ cell tumor, six cases of carcinoma in situ testis, and one Sertoli cell tumor. Three neoplasms were diagnosed in intra-abdominal testes, four in boys with abnormal external genitalia, and two in boys with known abnormal karyotype. Risk of neoplasia was 5% (7/150) in patients with intra-abdominal testis, abnormal external genitalia or diagnosed abnormal karyotype, versus 0% (0/1,185) in patients without these characteristics (FE, p < 0.00005). CONCLUSION: We recommend surgery for cryptorchidism before 15-18 months of age because: (a) lack of germ cells is very rare before, and (b) lack of germ cells is associated with subsequent risk of infertility. At primary surgery for cryptorchidism, we recommend examination for testicular neoplasia in cases of intra-abdominal testis, abnormal external genitalia or known abnormal karyotype.     

Hormonal treatment of cryptorchidism

Hormonal treatment of cryptorchidism with a gonadotropic substance from pregnancy urine or with an anterior-pituitary-like substance dates from the early 1930s. Success rates varied from 25 to 100%. Subsequently, human chorionic gonadotropin (hCG) administered intramuscularly came into use. The success rates of several large studies have varied from 25 to 55%. Widely divergent results have, likewise, been reported following the intranasal administration of luteinizing-hormone-releasing hormone (LHRH), the efficacy of which has been investigated in many studies, including placebo-controlled trials. Combined LHRH and hCG treatment schedules have been recently assessed, with equally divergent success rates. The most important factor influencing the rate of success is the testicular position before treatment: the lower the position of the testis before treatment the better the result. The experience with LHRH nasal spray treatment for cryptorchidism in 252 prepubertal boys is presented in this study, including several years follow-up, and the results compared with data reported in the literature.     

Cryptorchidie et température testiculaire

The testis migrates to a scrotal location before birth. This physiological descent is associated with a reduction in the temperature of the testicular environment since the temperature of the scrotal cavity is lower than that of the body one. This leads to the etablishment of a themperature gradient between the testis and the body which already exists in prepubertal boys. In cases of testicular maldescent (cryptorchidism), the temperature of the testis in its cryptorchid location is much higher than that of the normally descended contrlateral testis. However, there are no data obtained from human studies to establish wether the increased temperature of a cryptorchid testis is responsible for the spermatogenic perturbations typically observed. Nor do we know wether the relocation of a cryptorchid testis to the scrotum permits re-establishment of a normal testicular temperature. Adult men with a history of cryptorchidism constitute about 10% of infertile men, and among these previously cryptorchid infertile men 45% have an abnormally elevated scrotal temperature. This abnormal increase in scrotal temperature is a negative risk factor for fertility: these men have smaller testicular volumes, a more severely impaired spermatogenesis and a higher prevalence of primary infertility than previously cryptorchid infertile than previously cryptorchid infertile men with normal scrotal temperature. However, data provided until now do not allow to know whether elevated temperature is due to the decreased testicular size (hypotrophy) or is a consequence of cryptorchidism per se.     

Temporal changes in rat Leydig cell function after the induction of bilateral cryptorchidism

Adult rats were made bilaterally cryptorchid and studied at intervals of 3, 7, 14 or 21 days to study temporal changes in Leydig cell function. Serum FSH and LH levels were measured and the cross-sectional area of the Leydig cells assessed by morphometry. The function of the Leydig cells was judged by the binding of 125I-labelled hCG to testicular tissue in vitro and the testosterone response of the testis to hCG stimulation in vitro. By 3 days after cryptorchidism, the binding of labelled hCG to testicular tissue was significantly decreased compared to that of controls, but the testes were able to respond to hCG stimulation in vitro. At 7, 14 and 21 days after cryptorchidism, an enhanced testosterone response was observed and the size of the Leydig cells was significantly greater than that of the controls, which indicated increased secretory activity by the cryptorchid testis. Although serum FSH levels were significantly elevated after 3 days of cryptorchidism, serum LH levels did not rise until 7 days, thereby suggesting that the loss of receptors is unlikely to result from down-regulation by LH. The reduced testosterone response of the cryptorchid testis in vivo to low doses of hCG and the enhanced response at high doses are probably related to the reduced blood flow to the cryptorchid testis and the decreased sensitivity of the Leydig cells induced by LH/hCG receptor loss.     

Endocrine and immunological findings in cryptorchid infants

In cryptorchid infants, significantly decreased mean levels of plasma testosterone and luteinizing hormone (LH) were found between the ages of 30 and 120 days. The levels of testosterone and LH were significantly correlated. No significant difference was found between infants with bilateral or unilateral cryptorchidism. After 120 days there was no longer any significant difference between cryptorchid infants and controls. No significant change in plasma follicle-stimulating hormone (FSH) was found. These data suggest that subnormal secretion of LH could be the primary abnormality in a proportion of boys with so-called common cryptorchidism. Our studies using LH-releasing hormone and human chorionic gonadotropin stimulation tests in older infants and children agree with the data obtained by measurement of basal plasma hormone levels during the first months of life. Anti-gonadotroph antibodies were found in the sera of approximately 50% of the cryptorchid children and infants studied, using an immunofluorescence technique. A study of 17 mothers and their infants gave concordant results in 16 pairs, 9 with and 7 without antibodies. This lead us to speculate on the possible role of maternal autoantibodies as a cause of partial gonadotrophin deficiency in the perinatal period and thus of testicular maldescent. As cryptorchidism is a syndrome, these findings do not mean that a similar mechanism is operative in all cases. However, these data do suggest that alternatives to the classical anatomical view of the descent and nondescent of the testes should be considered.     

13 Years' experience with the combined hormonal therapy of cryptorchidism.

PURPOSE: We analyze the results of the combined treatment with luteinizing hormone releasing hormone (LH-RH) and human chorionic gonadotropin (HCG) of a large series of patients with cryptorchidism. MATERIALS AND METHODS: Between 1987 and 1999 and after strict differentiation between cryptorchid, retractile and gliding testes, 2,467 boys with 2,962 cryptorchid-gliding testes were treated with the combined hormonal therapy. LH-RH was administrated as a nasal spray at a dosage of 1.2 microg daily for a period of 4 weeks. HCG was injected intramuscularly, 5 times at 2-day intervals at a dosage adjusted according to the age. RESULTS: In the prospective study 2,476 boys with 2,962 cryptorchid testes were hormonally treated. Of the 2,962 evaluated cases 1,200 (40.52%) have been treated surgically after the hormone therapy. In 1,762 cases, 59.48% of cryptorchid testes were in the scrotum after combined hormone treatment. CONCLUSIONS: Treatment with LH-RH and HCG induced the descent of the testes to a normal scrotal position of boys with cryptorchidism in 59.48% of the evaluated cases. The combined treatment was effective for inducing descent of cryptorchid and gliding testes. According to the evaluated intraoperative findings, the failure of the combined therapy in 40.52% of the cases is due to the fact that the free descent is limited by local factors such as anatomical alterations of the inguinal canal, epididymal abnormalities or ectopic distal attachment of the lig. testis.     

Cryptorchidism: an indicator of testicular dysgenesis?

Cryptorchidism is a common ailment of new-born boys, affecting 1–9% of full term boys at birth. Cryptorchidism has been associated with an increased risk of testicular cancer and reduced fertility. Aetiology of cryptorchidism remains obscure in most cases. Familial occurrence suggests a heritable susceptibility to cryptorchidism; however, seasonal variation in the incidence of cryptorchidism suggests that environmental factors also contribute. Testicular descent is characterised by androgen-dependent regression of cranial suspensory ligament and androgen + insulin-like hormone 3 (Insl3)-dependent gubernacular outgrowth. Even though hormonal defects are rarely detected in patients, both hypo-and hypergonadotropic hormonal patterns have been associated with cryptorchidism. Moreover, cryptorchid boys have significantly reduced serum androgen bioactivity at 3 months of age when normal boys have a strong surge of reproductive hormones. Defects in Insl3 action cause cryptorchidism in male mice, and over-expression in female mice causes ovarian descent. Defects in leucine-rich repeat-containing G-protein-coupled receptor 8/G-protein-coupled receptor affecting testis descent (LGR8/GREAT), the receptor for Insl3, manifest the same phenotype as Insl3 knockout mutants. Even though mutations found in Insl3 and LGR8/GREAT genes are not a common cause of cryptorchidism in patients, it remains to be resolved whether low Insl3 levels during development are associated with cryptorchidism. Cryptorchidism may reflect foetal testicular dysgenesis that may later manifest as subfertility or testicular cancer.This work was supported by the Turku University Central Hospital, the Academy of Finland and the European Commission (contracts BMH4-CT96-0314, QLK4-CT1999-01422, QLK4-CT2001-00269 and QLK4-CT2002-00603).     

Steel-Dickie (Sld) mutation affects both maintenance and differentiation of testicular germ cells in mice.

The effects of Steel-Dickie (Sld) mutations on testicular germ cell differentiation were investigated using experimental cryptorchidism and its surgical reversal in mutant, C57BL/6-Sld/+ and wild-type C57BL/6- +/+ mice. In Sld/+ cryptorchid testes the maintenance of undifferentiated type-A spermatogonia was impaired and their numbers decreased. In contrast, the proliferative activity of type-A spermatogonia in the cryptorchid testis of mutant mice appeared normal as judged by their progression through the cell cycle. Surgical reversal of cryptorchidism resulted in regenerative differentiation of mature germ cells in +/+ testes. However, the regenerative differentiation of type-A spermatogonia which remained in Sld/+ cryptorchid testes was strongly impaired, particularly at two steps of cellular differentiation, from type-A spermatogonia to intermediate or type-B spermatogonia and at meiotic division. Furthermore, in mutant mice, no significant recovery of testicular weight was observed after surgical reversal compared with +/+ mice.     

hCG treatment raises H<Subscript>2</Subscript>O<Subscript>2</Subscript> levels and induces germ cell apoptosis in rat testis

The clinical significance of exogenous hCG treatment is to stimulate steroidogenesis and spermatogenesis in the testis. However, the pathogenesis of detrimental effects on the testis arising out of chronic hCG treatment is yet to be clearly ascertained. In the present study we have shown that hCG treatment (100 IU/day) to rats for 30 days raises testicular oxidative stress leading to germ cell apoptosis and impairment of spermatogenesis. The treatment raises testicular H₂O₂ levels along with increase in lipid peroxidation and concomitant decrease in the enzymatic antioxidant activities like superoxide dismutase, catalase and glutathione-s-transferase. The rise in the number of apoptotic germ cells was associated with up regulation of Fas protein expression and caspase-3 activity in the testis. However, serum testosterone which was elevated by 15 days of hCG treatment declined to pretreatment levels by 30 days. No significant alteration in serum gonadotropins was observed. The above findings indicate that the pathogenesis of deleterious effects following chronic hCG treatment is due to increase in testicular oxidative stress with high H₂O₂ availability leading to apoptosis among germ cells.