Low Serum Inhibin B/FSH and AMH/FSH Ratios as Markers of Decreased Germ Cells in Infants With Bilateral Cryptorchidism

Follicle stimulating hormone (FSH) in short-term rat studies supports spermatogenesis at multiple levels, notably spermatogonial development. The role of FSH in supporting full spermatogenesis in rats is still in question as long-term studies have not been possible due the development of neutralising antibodies to heterologous FSH preparations. This study sought to assess the effects of a homologous recombinant rat FSH (rr-FSH) preparation on the long-term restoration of spermatogenesis. Adult rats were GnRH-immunised (GnRH-im) for 12 weeks then, administered an anti-androgen; flutamide (flut), alone or together with rr-FSH (8µg/rat/daily) for 56 days (1 spermatogenic cycle). Germ and Sertoli cell numbers were quantified using an optical disector stereological method. Testis weight, serum FSH and inhibin B and Sertoli cell nuclear volume were significantly reduced to 15%, 13%, 25% and 57% of controls respectively, following GnRH-im+flut treatment. GnRH-im+flut treatment reduced A/I spermatogonial, type B spermatogonial+preleptotene, leptotene+zygotene and early pachytene spermatocyte numbers to 28%, 68%, 50% and 19% (P < 0.001) of controls respectively, with later germ cells rarely observed. After FSH treatment, no significant affect on testis weight, serum FSH and inhibin B or Sertoli cell number were observed. However, rr-FSH treatment significantly increased numbers of A/I spermatogonia, leptotene+zygotene and early pachytene spermatocytes from 28 = >42%, 50 = >69% and 19 = >27% of controls, respectively, while no differences were observed in later germ cell types. rr-FSH also increased (P < 0.05) the volume of Sertoli cell nuclei from 57 = >66% of control. In conclusion, FSH is unable to support full rat spermatogenesis; however, FSH can partially support germ cells notably spermatogonia through to early pachytene spermatocytes, despite the absence of androgenic support.

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Inhibin B in male reproduction: pathophysiology and clinical relevance

Acta Endocrinologica ◽

10.1530/eje.0.1450561 ◽

2001 ◽

Vol 145 (5) ◽

pp. 561-571 ◽

Cited By ~ 150

Author(s):

SJ Meachem ◽

E Nieschlag ◽

M Simoni

Keyword(s):

Germ Cells ◽

Sertoli Cells ◽

Clinical Relevance ◽

Feedback Mechanism ◽

Male Reproduction ◽

Inhibin B ◽

Testicular Sperm Extraction ◽

Specific Marker ◽

Negative Feedback Mechanism ◽

Normal Men

The recent availability of specific inhibin assays has demonstrated that inhibin B is the relevant circulating inhibin form in the human male. Inhibin B is a dimer of an alpha and a betaB subunit. It is produced exclusively by the testis, predominantly by the Sertoli cells in the prepubertal testis, while the site of production in the adult is still controversial. Inhibin B controls FSH secretion via a negative feedback mechanism. In the adult, inhibin B production depends both on FSH and on spermatogenic status, but it is not known in which way germ cells contribute to inhibin B production. The regulation of inhibin B production changes during life. There is an inhibin B peak in serum shortly after birth only partly correlated with an increase in serum FSH, probably reflecting the proliferating activity of the Sertoli cells during this phase of life. Afterwards, inhibin B levels decrease and remain low until puberty, when they rise again, first as a consequence of FSH stimulation and then as a result of the combined regulation by FSH and the ongoing spermatogenesis. In the adult, serum inhibin B shows a clear diurnal variation closely related to that of testosterone. The administration of FSH increases the secretion of inhibin B in normal men, but is much more pronounced in males with secondary hypogonadism. The treatment of infertile men with FSH, however, does not result in an unequivocal inhibin B increase. There is a clear inverse relationship between serum inhibin B and FSH in the adult. Serum inhibin B levels are strongly positively correlated with testicular volume and sperm counts. In infertile patients, inhibin B decreases and FSH increases. In general, there is very good correlation with the degree of spermatogenetic damage, with the arrest at the earlier stages having the lowest inhibin B levels. However, for unknown reasons, there are cases of Sertoli-cell-only syndrome with normal inhibin B levels. Inhibin B and FSH together are a more sensitive and specific marker for spermatogenesis than either one alone. However, the inhibin B concentrations are not a reliable predictor of the presence of sperm in biopsy samples for testicular sperm extraction. Suppression of spermatogenesis with testosterone and gestagens leads to a partial reduction of inhibin B in serum but it is never completely suppressed. In contrast, testicular irradiation in monkeys or humans leads to a rapid and dramatic decrease of inhibin B, which becomes undetectable when germ cells are completely absent. In summary, although inhibin B is a valuable index of spermatogenesis, the measurement of serum inhibin B levels is still of limited clinical relevance for individual patients.

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The relation of germ cells per tubule in testes, serum inhibin B and FSH in cryptorchid boys

Pediatric Surgery International ◽

10.1007/s00383-006-1839-9 ◽

2006 ◽

Vol 23 (2) ◽

pp. 163-169 ◽

Cited By ~ 17

Author(s):

D. Cortes ◽

J. Thorup ◽

E. Hogdall ◽

B. Norgaard-Pedersen ◽

B. L. Petersen ◽

...

Keyword(s):

Germ Cells ◽

Inhibin B

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Serum inhibin B, FSH, LH and testosterone levels before and after human chorionic gonadotropin stimulation in prepubertal boys with cryptorchidism

Acta Endocrinologica ◽

10.1530/eje.0.1470095 ◽

2002 ◽

Vol 147 (1) ◽

pp. 95-101 ◽

Cited By ~ 31

Author(s):

P Christiansen ◽

AM Andersson ◽

NE Skakkebaek ◽

A Juul

Keyword(s):

Chorionic Gonadotropin ◽

Human Chorionic Gonadotropin ◽

Sertoli Cells ◽

Cell Function ◽

Serum Levels ◽

Inhibin B ◽

Seminiferous Tubules ◽

Bilateral Cryptorchidism ◽

Prepubertal Boys ◽

Baseline Levels

BACKGROUND: Several studies have indicated that cryptorchidism is associated with degenerative changes in both Sertoli cells and germ cells. The gonadal peptide hormone inhibin B reflects Sertoli cell function. Low inhibin B levels are found in a large portion of formerly cryptorchid men who show compromised seminiferous tubule function. It is not known if inhibin B can be used to demonstrate early damage of seminiferous tubules in prepubertal boys with cryptorchidism. METHODS: We investigated the relationship between serum levels of inhibin B, testosterone, FSH and LH in 62 prepubertal boys with uni- and bilateral cryptorchidism. Furthermore, we investigated the changes in serum levels of inhibin B and the corresponding changes in serum levels of FSH, LH and testosterone during a short course (3 weeks) of human chorionic gonadotropin (hCG) injections in 18 of these cryptorchid boys. RESULTS: In the 62 prepubertal boys with uni- or bilateral cryptorchidism there were no significant differences in baseline levels (median and range) of inhibin B (88 (20-195) pg/ml vs 78 (35-182) pg/ml; not significant), LH (0.08 (<0.05-0.99) IU/l vs 0.06 (<0.05-1.61) IU/l; not significant) and FSH (0.60 (0.08-3.73) IU/l vs 0.85 (0.25-2.55); not significant) compared with 156 healthy prepubertal boys, and there were no differences in hormonal levels between boys with uni- or bilateral cryptorchidism. There was no correlation between baseline levels of inhibin B and FSH. In boys younger than 9 years, we found no correlation between baseline levels of inhibin B and LH whereas, in boys older than 9 years, baseline levels of inhibin B were positively correlated to baseline LH (Spearman rank correlation coefficient ((R(s))=0.58, P=0.03). Treatment with hCG (1500 IU intramuscularly twice weekly for 3 weeks) resulted in descensus of testes in 9 out of 18 patients. In all boys but one, irrespective of age, hCG induced a marked increase in testosterone into the adult range (from undetectable to 21.8 (7.0-35.4) nmol/l; P<0.001) and completely suppressed FSH and LH levels. Serum levels of inhibin B increased significantly from 116 (50-195) pg/ml to 147 (94-248) pg/ml (P<0.05), but not uniformly. The increase in serum levels of inhibin B was inversely correlated to baseline inhibin B (Rs=-0.52, P=0.03) and baseline FSH (R(s)=-0.59, P<0.01). CONCLUSIONS: We therefore suggest that, in the prepubertal testes, inhibin B is secreted from the prepubertal Sertoli cells following hCG, whereas early pubertal testes with more differentiated Sertoli cells are not able to secrete inhibin B in response to hCG stimulation, perhaps due to lack of germ cell-derived betaB-subunits. We found (a) normal inhibin B levels in prepubertal boys with uni- or bilateral cryptorchidism, (b) that hCG stimulated testosterone markedly and suppressed FSH and LH levels and (c) that hCG treatment stimulated inhibin B levels in the youngest cryptorchid boys. In the oldest prepubertal boys no hCG-induced changes in inhibin B were shown.

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Distinguishing between hidden testes and anorchia: the role of endocrine evaluation in infancy and childhood

Acta Endocrinologica ◽

10.1530/eje-20-0041 ◽

2020 ◽

Vol 183 (1) ◽

pp. 107-117 ◽

Cited By ~ 1

Author(s):

Kirstine Jespersen ◽

Marie Lindhardt Ljubicic ◽

Trine Holm Johannsen ◽

Peter Christiansen ◽

Niels E Skakkebaek ◽

...

Keyword(s):

Hypogonadotropic Hypogonadism ◽

Testicular Tissue ◽

Diagnostic Value ◽

Reproductive Hormones ◽

Inhibin B ◽

Control Group ◽

Serum Concentrations ◽

Diagnostic Challenge ◽

Bilateral Cryptorchidism ◽

Wide Range

Objective Non-palpable testes remain a diagnostic challenge, often involving exploratory laparoscopy. We evaluated the diagnostic value of a wide range of reproductive hormones in order to distinguish between bilateral cryptorchidism and bilateral anorchia. Design In this retrospective study, we identified and included 36 boys with non-palpable testes (20 with cryptorchidism, 3 with congenital hypogonadotropic hypogonadism (CHH), and 13 with anorchia) at first examination during childhood. Methods Information on karyotype, phenotype, surgical results from laparoscopy, and biochemistry was retrieved from patient files. We compared serum concentrations of AMH, inhibin B, FSH, LH, testosterone, estradiol, and hCG stimulation testing in cryptorchid and anorchid boys to serum concentrations in a large, age-matched control group. Receiver-operating characteristic curves were used to determine the cut-off values of each reproductive hormone as a predictor of the presence of functional testicular tissue. Results Concentrations of AMH in 0–1 year olds: ≥155 pmol/L and >1–15 year olds: ≥19 pmol/L, inhibin B (≥22 pg/mL and ≥4 pg/mL), FSH (≤28.9 IU/L and ≤20.3 IU/L) and hCG-induced testosterone (>1-15 year olds: ≥2 nmol/L) were significantly sensitive and specific markers in predicting the presence of functional testicular tissue in boys with non-palpable testes. In infancy, anorchid infants had significantly elevated gonadotropin levels, while CHH had low levels. Conclusion Our findings suggest that laparoscopy may not be necessary in all boys with non-palpable testes if reproductive hormones unequivocally confirm the presence of functional testicular tissue. However, proving the absence may still be a diagnostic challenge.

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Inhibin B plasma concentrations in infertile patients with DAZ gene deletions treated with FSH

Acta Endocrinologica ◽

10.1530/eje.0.1460801 ◽

2002 ◽

pp. 801-806 ◽

Cited By ~ 6

Author(s):

C Foresta ◽

A Bettella ◽

E Moro ◽

M Rossato ◽

M Merico ◽

...

Keyword(s):

Y Chromosome ◽

Sertoli Cell ◽

Germ Cells ◽

Sertoli Cells ◽

Cell Function ◽

Plasma Concentrations ◽

Inhibin B ◽

Azoospermia Factor ◽

Deleted In Azoospermia ◽

Factor C

OBJECTIVE: The DAZ (deleted in azoospermia) gene family on the Y chromosome long arm is the major candidate for the AZFc (azoospermia factor c) phenotype of male infertility and it is expressed only in germ cells. The aim of the study was to assess Sertoli cell function in subjects with AZFc deletions. DESIGN: Case-control, prospective study. METHODS: We have studied six severely oligozoospermic subjects with AZFc-DAZ deletions, and looked whether they responded in terms of inhibin B production to a 1 month FSH treatment. These patients were compared with three groups of patients affected by different spermatogenic alterations not related to deletions on the Y chromosome. RESULTS: Although affected by severe testiculopathy, patients with AZFc-DAZ deletions had only slightly elevated FSH, and normal inhibin B plasma concentrations. Inhibin B responded normally during FSH treatment, supporting the hypothesis that Sertoli cells are not altered. On the contrary, other severe testiculopathies not related to Y chromosome deletions showed high FSH and low inhibin B concentrations, with no response to FSH treatment. In these cases the cause of the spermatogenic defect probably damaged both germ and Sertoli cells. Finally, idiopathic patients with a hormonal status similar to Y-deleted patients (slightly elevated FSH and normal inhibin B concentrations) did not respond to FSH treatment, suggesting that Sertoli cells were already at their maximal functional capability. CONCLUSIONS: These data confirm that Sertoli cell function is not damaged in patients with AZFc-DAZ deletions and that the strong reduction of germ cells does not affect the FSH-inhibin B feedback loop.

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