Suppression of spermatogenesis by exogenous testosterone

2020 ◽  
Vol 26 ◽  
Author(s):  
Ferdinando Fusco ◽  
Paolo Verze ◽  
Marco Capece ◽  
Luigi Napolitano
Keyword(s):  
Male Fertility ◽  
Leydig Cells ◽  
Sperm Count ◽  
Sperm Concentration ◽  
Seminiferous Tubules ◽  
Sperm Production ◽  
Long Term Effects ◽  
Fertility Status ◽  
Normal Spermatogenesis

: Sperm production starts from puberty in the seminiferous tubules providing for testosterone production by the Leydig cells taking place in the interstice of the testicles. Normal spermatogenesis depends on specific signalling from the hypothalamic-pituitary-gonadal axis. GnRH, FSH and LH are the main hormones involved in the production and maturation of spermatozoa. Exogenous administration of androgens influences the hypothalamic-pituitary-gonadal axis with negative feedback that may lead to partial or complete cessation of spermatogenesis by decreasing FSH and LH. Despite the fact that many trials have confirmed that exogenous testosterone affects male fertility status, evidence regarding the long-term effects of treatment is conflicting. Regarding this aspect, many studies have confirmed a return to baseline sperm concentration after testosterone treatment discontinuation, however none of them can specify how long recovery will take nor whether the sperm count is sufficient for fertility.

scholarly journals Effect of early immunocastration on testicular histology in pigs

2018 ◽  
Vol 63 (No. 1) ◽  
pp. 18-27 ◽  
Author(s):  
Z. Sladek ◽  
M. Prudikova ◽  
A. Knoll ◽  
P. Kulich ◽  
I. Steinhauserova ◽  
...  
Keyword(s):  
Endocrine Cells ◽  
Booster Dose ◽  
Seminiferous Tubules ◽  
Control Group ◽  
Long Term Effects ◽  
Normal Spermatogenesis ◽  
Short And Long Term ◽  
Testicular Histology ◽  
Delayed Time

The objective of this study was to investigate short- and long-term effects of early immunocastration with Improvac<sup>®</sup> vaccine, administered in two doses, at ages eight and 14 weeks, on testicular histology in pigs slaughtered eight or 15 weeks after the second dose. We hypothesised that the effectiveness of early vaccination could be diminished by late application of the booster dose and/or delayed time of slaughter. Thirty non-castrated male pigs of a commercial hybrid breed were used in this study. Pigs (n = 15) in the control group (NOCA) remained intact throughout the study. Pigs (n = 15) in the experimental group (IMCA) were administered Improvac in two doses: a priming dose at eight weeks and a booster dose at 14 weeks. Subsequently, nine of the IMCA pigs were slaughtered at eight weeks and the remaining six at 15 weeks after the second dose. In NOCA pigs, we observed normal spermatogenesis in the tubuli seminiferi and many prominent interstitial endocrine (Leydig) cells. In IMCA<sub>8</sub> pigs, there was a noticeable decrease in the diameter and area of seminiferous tubules and spermatogenesis was absent. Interstitial endocrine cells appeared atrophied with pyknotic nuclei. In IMCA<sub>15</sub> pigs, we observed a larger diameter of tubuli, thickened germinal epithelium and larger and more numerous interstitial endocrine cells when compared to IMCA<sub>8</sub>. In conclusion, these results demonstrate that early immunocastration with Improvac disrupts spermatogenesis and reduces the number and size of interstitial endocrine cells. This indicates that vaccination at an age of eight weeks and again at 14 weeks in pigs causes disruption of testicular histology and spermatogenesis at least through the subsequent 15 weeks.

scholarly journals Urinary Bisphenol A, F and S Levels and Semen Quality in Young Adult Danish Men

2021 ◽  
Vol 18 (4) ◽  
pp. 1742
Author(s):  
Thea Emily Benson ◽  
Anne Gaml-Sørensen ◽  
Andreas Ernst ◽  
Nis Brix ◽  
Karin Sørig Hougaard ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Male Fertility ◽  
Parental Education ◽  
Negative Binomial ◽  
Semen Quality ◽  
Sperm Count ◽  
Smoking Status ◽  
Sperm Concentration ◽  
First Trimester ◽  
Negative Binomial Regression Model

Bisphenol A (BPA) is considered an endocrine disruptor and has been associated with deleterious effects on spermatogenesis and male fertility. Bisphenol F (BPF) and S (BPS) are structurally similar to BPA, but knowledge of their effects on male fertility remains limited. In this cross–sectional study, we investigated the associations between exposure to BPA, BPF, and BPS and semen quality in 556 men 18–20 years of age from the Fetal Programming of Semen Quality (FEPOS) cohort. A urine sample was collected from each participant for determination of BPA, BPF, and BPS concentrations while a semen sample was collected to determine ejaculate volume, sperm concentration, total sperm count, sperm motility, and sperm morphology. Associations between urinary bisphenol levels (continuous and quartile–divided) and semen characteristics were estimated using a negative binomial regression model adjusting for urine creatinine concentration, alcohol intake, smoking status, body mass index (BMI), fever, sexual abstinence time, maternal pre–pregnancy BMI, and first trimester smoking, and highest parental education during first trimester. We found no associations between urinary bisphenol of semen quality in a sample of young men from the general Danish population.

OBSERVATIONS ON CADMIUM DAMAGE AND REPAIR IN RAT TESTES AND THE EFFECTS ON THE PITUITARY GONADOTROPHS

1962 ◽  
Vol 24 (4) ◽  
pp. 453-NP ◽  
Author(s):  
M. ALLANSON ◽  
R. DEANESLY
Keyword(s):  
Subcutaneous Injection ◽  
Cadmium Chloride ◽  
Cytological Study ◽  
Interstitial Cells ◽  
Germinal Epithelium ◽  
Seminiferous Tubules ◽  
Interstitial Tissue ◽  
Long Term Effects ◽  
Single Subcutaneous Injection

SUMMARY Cadmium chloride, in a single subcutaneous injection, can destroy spermatogenic and interstitial cells in the rat testis (Pařízek, 1957) and produce changes in the pituitary. The interstitial tissue is restored by ingrowths from the tunica and full androgen secretion returns before there is any regeneration of germinal epithelium. A cytological study has been made of the peripheral and central pituitary gonadotrophs; the latter revert almost to normal as the interstitial tissue regenerates, whereas the former retain characteristic castration features, unless there is also regeneration of the germinal epithelium. This seems to indicate that in the normal testis there is a hormone contribution from the seminiferous tubules as well as from the interstitial cells. The long-term effects of cadmium on the testis depend on the dose. Early stages of tubule restoration have been studied, but after administration of 0·9 mg., actual proliferation of the germinal epithelium was rarely found—only in four out of twenty rats, 113 or 142 days after injection.

scholarly journals REPRODUCING QUALITIES OF RAMS OF THE MOLDOVAN TYPE KARAKUL BREED

2020 ◽  
Vol 59 ◽  
pp. 92-96
Author(s):  
D. Rotari
Keyword(s):  
Sperm Count ◽  
Sperm Concentration ◽  
Animal Husbandry ◽  
Sperm Production ◽  
Livestock Farming ◽  
High Quality ◽  
Average Percentage ◽  
Reproductive Ability ◽  
First Time

Issues related to the reproduction of animals have been and remain one of the most complex and relevant problems of biology and are constantly finding a direct and effective way out into livestock farming practice. The rational use of breeding sheep as producers is limited by the lack of standard, objective methods and methods for the timely assessment of their reproductive ability. The article presents the results of evaluating the sperm production of rams-producers. For the first time, the freshly obtained sperm of rams of Moldavian type producers of the Karakul breed was evaluated using the macroscopic method - ejaculate volume, color and smell, as well as the microscopic method - motility, sperm concentration in the ejaculate, total sperm count in the ejaculate sperm movements (VAP; VSL and VCL) as well as the percentage of abnormal forms of sperm. The experiments were carried out on sheep producers grown on a pedigree farm of the experimental farm of the Moldavian Scientific and Practical Institute of Biotechnology in Animal Husbandry and Veterinary Medicine. As a result of the studies, it was found that the ejaculate volume on average was 0.99 ± 0.04 ml, motility was 0.95 ± 0.02 and sperm concentration 1.51 ± 0.14 billion/ml. The percentage of pathological forms in sperm averaged 13.72 ± 0.61, an indicator that characterizes the high quality of sperm. The average quality indicator of ejaculates obtained from ram-producers of the Moldavian type of the Karakul breed corresponds to physiological standards for the Karakul breed. The average percentage of pathological forms of sperm found in ejaculates indicates that the rams were in good conditions of feeding and keeping. According to research, we can say that the Moldovan type of Karakul rams can be successfully used to obtain high quality ejaculates suitable for freezing sperm at 196°C.

scholarly journals Semen quality and diversity of morphological sperm abnormalities in bulls: breed and strain effects

2019 ◽  
Vol 22 (8) ◽  
pp. 931-938
Author(s):  
M. A. Kleshchev ◽  
V. L. Petukhov ◽  
L. V. Osadchuk
Keyword(s):  
Sperm Motility ◽  
Environmental Conditions ◽  
Western Siberia ◽  
Semen Quality ◽  
Sperm Count ◽  
Sperm Concentration ◽  
Sperm Head ◽  
Sperm Dna Fragmentation ◽  
Sperm Production ◽  
Sperm Abnormalities

At present great attention is paid to studying genetic regulation of farm animal adaptations to environmental conditions. This problem is very important due to a wide expansion of highly productive cattle breeds created in Europe and North America. However, until the present no investigation of changing semen quality in bulls of imported breeds during their adaptations to environmental conditions of Western Siberia has been conducted. The aim of this study was to investigate semen quality peculiarities and the diversity of morphological sperm abnormalities in bulls of imported and local breeds kept in the environmental conditions of the southern part of Western Siberia. We determined sperm concentration, sperm count, and rate of sperm with progressive motility and percentage of morphologically normal spermatozoa. The rate of sperm abnormalities according to Blome’s classifcation was determined too. It was found that the mean values of sperm concentration, sperm motility and percentage of morphologically normal spermatozoa in the bulls investigated were similar to those in bulls kept in European countries. Inter­breed differences in these parameters were not found. However, bulls of the Red Danish, Angler, and Simmental breeds had a higher percentage of misshapen sperm head and pyriform sperm head than bulls of the Black­White breed. An inter­strain difference in sperm motility in bulls of the Black­White breed was observed. It was found that bulls of Reflection Sovereign 198998 strain had lover sperm motility than bulls of Wis Burke Ideal 1013415 strain. No inter­strain differences in sperm production, percentage of morphologically normal spermatozoa and rate of main sperm abnormalities were found. Thus, it has been found that the environmental conditions of the southern part of Western Siberia do not seriously affect the sperm production, sperm motility or percentage of morphologically normal spermatozoa in bulls. However, the increased rate of misshapen and pyriform sperm heads in the bulls of the foreign breeds points to a need to study sperm DNA fragmentation.

scholarly journals Influence of long-term dietary administration of procymidone, a fungicide with anti-androgenic effects, or the phytoestrogen genistein to rats on the pituitary–gonadal axis and Leydig cell steroidogenesis

2005 ◽  
Vol 187 (1) ◽  
pp. 117-124 ◽  
Author(s):  
K Svechnikov ◽  
V Supornsilchai ◽  
M-L Strand ◽  
A Wahlgren ◽  
D Seidlova-Wuttke ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Serum Level ◽  
Leydig Cell ◽  
Leydig Cells ◽  
Ex Vivo ◽  
Elevated Serum ◽  
Seminiferous Tubules ◽  
Dibutyryl Camp

Procymidone is a fungicide with anti-androgenic properties, widely used to protect fruits from fungal infection. Thereby it contaminates fruit products prepared for human consumption. Genistein-containing soy products are increasingly used as food additives with health-promoting properties. Therefore we examined the effects of long-term dietary administration (3 months) of the anti-androgen procymidone (26.4 mg/animal per day) or the phytoestrogen genistein (21.1 mg/animal per day) to rats on the pituitary-gonadal axis in vivo, as well as on Leydig cell steroidogenesis and on spermatogenesis ex vivo. The procymidone-containing diet elevated serum levels of LH and testosterone and, furthermore, Leydig cells isolated from procymidone-treated animals displayed an enhanced capacity for producing testosterone in response to stimulation by hCG or dibutyryl cAMP, as well as elevated expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 side-chain cleavage (P450 scc) and cytochrome P450 17α (P450c17). In contrast, the rate of DNA synthesis during stages VIII and IX of spermatogenesis in segments of seminiferous tubules isolated from genistein-treated rats was decreased without accompanying changes in the serum level of either LH or testosterone. Nonetheless, genistein did suppress the ex vivo steroidogenic response of Leydig cells to hCG or dibutyryl cAMP by down-regulating their expression of P450 scc. Considered together, our present findings demonstrate that long-term dietary administration of procymidone or genistein to rats exerts different effects on the pituitary–gonadal axis in vivo and on Leydig cell steroidogenesis ex vivo. Possibly as a result of disruption of hormonal feedback control due to its anti-androgenic action, procymidone activates this endocrine axis, thereby causing hyper-gonadotropic activation of testicular steroidogenesis. In contrast, genistein influences spermatogenesis and significantly inhibits Leydig cell steroidogenesis ex vivo without altering the serum level of either LH or testosterone.

Rapid recovery of spermatogenesis after mitoxantrone, vincristine, vinblastine, and prednisone chemotherapy for Hodgkin's disease.

1997 ◽  
Vol 15 (12) ◽  
pp. 3488-3495 ◽  
Author(s):  
M L Meistrich ◽  
G Wilson ◽  
K Mathur ◽  
L M Fuller ◽  
M A Rodriguez ◽  
...  
Keyword(s):  
Hodgkin's Disease ◽  
Male Fertility ◽  
Sperm Count ◽  
Hodgkin’S Disease ◽  
Spermatogenic Cells ◽  
Sperm Production ◽  
Human Male ◽  
Sperm Counts ◽  
Abdominal Radiotherapy ◽  
Upper Abdominal

PURPOSE Because the effects of mitoxantrone on human male fertility were unknown, we determined prospectively the effects of three courses of mitoxantrone (Novantrone), vincristine (Oncovin), vinblastine, prednisone (NOVP) chemotherapy on the potential for fertility of men with Hodgkin's disease (HD). PATIENTS AND METHODS Semen analyses were performed on 58 patients with stages I-III HD before, during, and after chemotherapy and after the sperm count recovered from the effects of abdominal radiotherapy that was given after chemotherapy. RESULTS Before the initiation of treatment, 84% of the patients were normospermic. Sperm counts declined significantly within 1 month after the start of NOVP chemotherapy. In the month after chemotherapy, 38% of patients were azoospermic, 52% had counts < 1 million/ mL, and 10% had counts between 1 and 3 million/mL. Between 2.6 and 4.5 months after the completion of chemotherapy, sperm counts recovered rapidly to normospermic levels in 63% of patients. In the remaining patients who were followed up for at least 1 year after standard upper abdominal radiotherapy, counts also recovered to normospermic levels. CONCLUSION NOVP chemotherapy, like most other regimens, produced marked temporary effects or spermatogenesis. However, sperm production recovered very rapidly, within 3 to 4 months after the end of NOVP chemotherapy. This pattern was caused by killing differentiating spermatogenic cells, but there was little cytotoxicity or inhibition of stem cells from mitoxantrone or the other drugs. After the combination of NOVP plus abdominal radiotherapy, sperm counts and motility were restored in most patients to pretreatment levels, which were compatible with normal fertility.

Testicular oxytocin: effects of intratesticular oxytocin in the rat

1991 ◽  
Vol 130 (2) ◽  
pp. 231-NP ◽  
Author(s):  
H. D. Nicholson ◽  
S. E. F. Guldenaar ◽  
G. J. Boer ◽  
B. T. Pickering
Keyword(s):  
Leydig Cells ◽  
Light And Electron Microscopy ◽  
Male Rats ◽  
Plasma Testosterone ◽  
Epididymal Sperm ◽  
Long Term Effects ◽  
Sperm Counts ◽  
Term Administration

ABSTRACT The long-term effects of oxytocin administration on the testis were studied using intratesticular implants. Adult male rats had an Accurel device containing 20 μg oxytocin (releasing approximately 200 ng/day) implanted into the parenchyma of each testis; control animals received empty devices. The animals were killed at weekly intervals for 4 weeks. Some animals were perfused and the testes processed for light and electron microscopy. Blood was collected from the remaining animals for the measurement of testosterone, dihydrotestosterone, LH, FSH and oxytocin; epididymal sperm counts were measured and the testes were extracted and radioimmunoassayed for testosterone, dihydrotestosterone and oxytocin. Long-term administration of oxytocin resulted in a significant reduction in testicular and plasma testosterone levels throughout the 4-week period examined and, after 14 days of treatment, lipid droplets were seen in the Leydig cells of treated but not control animals. Concentrations of dihydrotestosterone in the plasma and testes of the oxytocin-treated animals, however, were significantly elevated after 7 and 14 days and at no time fell below control values. Plasma FSH levels were also lower in the oxytocin-treated animals. Intratesticular oxytocin treatment did not affect LH or oxytocin concentrations in the plasma, epididymal sperm counts or the number of Leydig cells in the testis. Empty Accurel devices had no effect on testicular morphology. This study provides the first evidence that oxytocin in vivo can modify steroidogenesis in the testis. Journal of Endocrinology (1991) 130, 231–238

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