scholarly journals Use of Gonadotropic Hormones and Sex Steroids in Assessing Male Reproduction

1986 ◽  
Vol 5 (4) ◽  
pp. 235-247
Author(s):  
R. J. Witorsch

In this presentation we discuss how male reproductive hormones are influenced by various normal and abnormal situations. Puberty is characterized by a progressive increase in serum gonadotropins (FSH and LH) and testosterone. Hormonal profiles in aging men and rats differ significantly, suggesting qualitatively different age-related changes in both species. Gonadal disorders in humans may exhibit similar symptoms (such as delayed or precocious virilization) but may be due to different defects within the hypothalamo-pituitary-testicular axis and, hence, may exhibit different reproductive hormone profiles. Reproductive hormone measurements reveal that toxic agents, such as ketoconazole, alcohol, or opiates, can impair reproductive function at the gonad and/or the hypothalamo-pituitary level. Glucocorticoids released during stress have been shown to have a direct inhibitory effect on testosterone release from the testes, which may be of relevance to toxicology studies. Reproductive hormonal measurements have also revealed that LH levels in the blood fluctuate in a pronounced episodic fashion and that this pattern is due to the pulsatile delivery of GnRH to the anterior pituitary gland. Administration of GnRH in a pulsatile fashion to patients with hypogonadotropic hypogonadism restores gonadal function. Nonpulsatile GnRH delivery to the anterior pituitary suppresses LH and testosterone release, and, consequently, long-acting superanalogs of GnRH appear to be effective in the treatment of prostatic cancer and true precocious puberty. The examples presented in this article illustrate how hormonal measurements have increased our knowledge and understanding of male reproduction.

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Luigi MAIONE ◽  
Sylvie SALENAVE ◽  
Severine TRABADO ◽  
Philippe Chanson ◽  
Ursula B Kaiser ◽  
...  

Abstract Context. Hypogonadotropic hypogonadism (HH) is a clinical condition defined by subnormal serum testosterone levels with low serum gonadotropins, which leads to infertility and reduced testicular function in men. HH may be prenatal or congenital (CHH) or acquired (AHH), the latter most commonly related to injury at the hypothalamic/pituitary level. Since diverse medical specialists usually deal with these two disorders, a direct comparison of clinical characteristics and reproductive hormone levels in patients with CHH and AHH has never been performed in a large series. Patients and methods. 201 men with CHH (Kallmann syndrome 52%; normosmic CHH 48%) and 479 men with AHH were included. Causes for AHH included pituitary tumors (74.6%), other intracranial tumors (12.7%; craniopharyngioma 9.1%), infiltrative diseases (3.5%), and other causes (9.2%). We excluded patients with idiopathic late-onset or metabolically-related AHH from this analysis. Testicular volume (TV), serum gonadotropins, total and bioavailable testosterone (TT and BT), estradiol (E2) and testicular peptides inhibin B (IB), AMH and INSL3 were measured at a single center in the absence of any hormone replacement. Results. TV was greater in patients with AHH (16.2±6.3 mL) than in those with CHH (3.4±2.7 mL; p<0.0001). Testicular hypotrophy (mean TV<12 mL) was found in 30% of patients with AHH and in 97% of those with CHH (p<0.0001). When adjusted for age and BMI, men with AHH still had a larger mean TV than those with CHH (p<0.0001). Cryptorchidism was more frequent in patients with CHH than in those with AHH (20.4 vs 0.2%, p<0.0001). Micropenis was found exclusively in patients with CHH. TT levels were higher in patients with AHH (1.4±0.9 ng/mL) than in those with CHH (0.4±0.3 mL, p<0.0001). LH, FSH, BT and E2 were higher in patients with AHH than in those with CHH (p<0.0001 for all parameters), as were IB and INSL3 levels (126±87 vs 59±55 pg/mL, and 566±372 vs 60±40 pg/mL, respectively, p<0.001). In contrast, serum AMH and SHBG levels were lower in patients with AHH than in those with CHH (246±234 vs 46±38 pmol/L, and 35±22 vs 26±21 nmol/L, respectively, p<0.0001). Comparing hormone characteristics across different AHH subgroups, patients with craniopharyngioma (n=44) had lower TV (7.7±5.3 mL) and lower TT, BT, E2, IB and INSL3 levels than those with AHH caused by any other etiology (p<0.05 for all parameters). Conclusions. Our data demonstrate distinct profiles of clinical presentation and reproductive hormones between CHH and AHH. Clinical and hormonal impairment is more severe in patients with CHH than in those with AHH. Preservation of the gonadotrope/testicular axis activity during the fetal, neonatal and pubertal periods in patients with AHH likely accounts for these differences. Among AHH etiologies, patients with craniopharyngioma have the most severe impairment, likely as a result of the intrinsic severity of these tumors, the age at onset, and/or the aggressiveness of the available therapeutic procedures.


2005 ◽  
Vol 17 (5) ◽  
pp. 507 ◽  
Author(s):  
Ma Yuan ◽  
Zhou Wen-Xia ◽  
Cheng Jun-Ping ◽  
Zhang Yong-Xiang

To investigate age-related changes in the oestrous cycle and reproductive hormone levels in senescence-accelerated mouse (SAM), we examined these parameters in 3-, 5-, 7-, 9- and 11-month-old female SAM-prone/8 (SAMP8) and SAM-resistant/1 (SAMR1) strains. Levels of β-endorphin (β-EP) and substance P (SP) in the hypothalamus were also measured. The oestrous cycle and dioestrus of 9-month-old SAMP8 mice were significantly prolonged compared with age-matched SAMR1 mice. Furthermore, the concentration of serum oestradiol was lower and the level of pituitary luteinising hormone was higher in SAMP8 mice compared with SAMR1 mice. This characterises the hypothalamus–pituitary–ovary (HPO) axis of the SAMP8 strain as hypergonadotropic–hypogonad. The levels of β-EP and SP in the SAMP8 hypothalamus were lower than in the SAMR1 hypothalamus. These results indicate that the function of the HPO axis in SAMP8 mice declines early and this may be attributed, in part, to the decline in β-EP and SP concentrations in the hypothalamus.


2009 ◽  
Vol 21 (4) ◽  
pp. 624
Author(s):  
Ma Yuan ◽  
Zhou Wen-Xia ◽  
Cheng Jun-Ping ◽  
Zhang Yong-Xiang

To investigate age-related changes in the oestrous cycle and reproductive hormone levels in senescence-accelerated mouse (SAM), we examined these parameters in 3-, 5-, 7-, 9- and 11-month-old female SAM-prone/8 (SAMP8) and SAM-resistant/1 (SAMR1) strains. Levels of �-endorphin (�-EP) and substance P (SP) in the hypothalamus were also measured. The oestrous cycle and dioestrus of 9-month-old SAMP8 mice were significantly prolonged compared with age-matched SAMR1 mice. Furthermore, the concentration of serum oestradiol was lower and the level of pituitary luteinising hormone was higher in SAMP8 mice compared with SAMR1 mice. This characterises the hypothalamus.pituitary.ovary (HPO) axis of the SAMP8 strain as hypergonadotropic.hypogonad. The levels of �-EP and SP in the SAMP8 hypothalamus were lower than in the SAMR1 hypothalamus. These results indicate that the function of the HPO axis in SAMP8 mice declines early and this may be attributed, in part, to the decline in �-EP and SP concentrations in the hypothalamus.


2008 ◽  
Vol 93 (7) ◽  
pp. 2737-2745 ◽  
Author(s):  
Frederick C. W. Wu ◽  
Abdelouahid Tajar ◽  
Stephen R. Pye ◽  
Alan J. Silman ◽  
Joseph D. Finn ◽  
...  

Abstract Context: The cause of declining testosterone (T) in aging men and their relationships with risk factors are unclear. Objective: The objective of the study was to investigate the relationships between lifestyle and health with reproductive hormones in aging men. Design: This was a baseline cross-sectional survey on 3200 community-dwelling men aged 40–79 yr from a prospective cohort study in eight European countries. Results: Four predictors were associated with distinct modes of altered function: 1) age: lower free T (FT; −3.12 pmol/liter·yr, P < 0.001) with raised LH, suggesting impaired testicular function; 2) obesity: lower total T (TT; −2.32 nmol/liter) and FT (−17.60 pmol/liter) for body mass index (BMI; ≥ 25 to < 30 kg/m2) and lower TT (−5.09 nmol/liter) and FT (−53.72 pmol/liter) for BMI 30 kg/m2 or greater (P < 0.001–0.01, referent: BMI < 25 kg/m2) with unchanged/decreased LH, indicating hypothalamus/pituitary dysfunction; 3) comorbidity: lower TT (−0.80 nmol/liter, P < 0.01) with unchanged LH in younger men but higher LH in older men; and 4) smoking: higher SHBG (5.96 nmol/liter, P < 0.001) and LH (0.77 U/liter, P < 0.01) with increased TT (1.31 nmol/liter, P < 0.001) but not FT, compatible with a resetting of T-LH-negative feedback due to elevated SHBG. Conclusions: Complex multiple alterations in the hypothalamic-pituitary-testicular axis function exist in aging men against a background of progressive age-related testicular impairment. These changes are differentially linked to specific risk factors. Some risk factors operate independently of but others interact with age, in contributing to the T decline. These potentially modifiable risk factors suggest possible preventative measures to maintain T during aging in men.


2008 ◽  
Vol 24 (4-5) ◽  
pp. 277-286 ◽  
Author(s):  
Yunhui Zhang ◽  
Renshan Ge ◽  
Matthew P. Hardy

Leydig cells are the primary source of testosterone in the male, and differentiation of Leydig cells in the testes is one of the primary events in the development of the male body and fertility. Stem Leydig cells (SLCs) exist in the testis throughout postnatal life, but a lack of cell surface markers previously hindered attempts to obtain purified SLC fractions. Once isolated, the properties of SLCs provide interesting clues for the ontogeny of these cells within the embryo. Moreover, the clinical potential of SLCs might be used to reverse age-related declines in testosterone levels in aging men, and stimulate reproductive function in hypogonadal males. This review focuses on the source, identification and outlook for therapeutic applications of SLCs. Separate pools of SLCs may give rise to fetal and adult generations of Leydig cell, which may account for their observed functional differences. These differences should in turn be taken into account when assessing the consequences of environmental pollutants such as the phthalate ester, diethylhexylphthalate (DEHP).


2014 ◽  
Vol 11 (3) ◽  
pp. 57-58
Author(s):  
Teona Albertovna Shvangiradze

Metformin, widely used for the treatment of type 2 diabetes, is increasingly becoming the subject of research in other areas of medicine. Apart form antihyperglycemic effect of metformin has an inhibitory effect on the proliferation of various tumor cells both in vivo and in vitro. Metformin is well established in the treatment of anovulatory infertility in polycystic ovary syndrome, while its influence male reproductive function are poorly understood.


Bone Reports ◽  
2021 ◽  
Vol 14 ◽  
pp. 100833
Author(s):  
Graziana Colaianni ◽  
Lorenzo Sanesi ◽  
Giuseppina Storlino ◽  
Roberta Zerlotin ◽  
Patrizia Pignataro ◽  
...  

2013 ◽  
Vol 98 (11) ◽  
pp. 4464-4474 ◽  
Author(s):  
C. N. Jayasena ◽  
A. N. Comninos ◽  
G. M. K. Nijher ◽  
A. Abbara ◽  
A. De Silva ◽  
...  

Background: Kisspeptin is a critical hypothalamic regulator of reproductive function. Chronic kisspeptin administration causes profound tachyphylaxis in male monkeys and in women with functional hypothalamic amenorrhea. The pharmacological effects of chronic kisspeptin exposure in healthy women with normal menstrual cycles have not been studied previously. Aim: Our aim was to determine the effects of follicular-phase kisspeptin-54 treatment on menstrual cyclicity in healthy women. Methods: We performed a prospective, single-blinded, 1-way crossover study. Healthy women received twice-daily sc injections of kisspeptin (6.4 nmol/kg) or 0.9% saline during menstrual days 7–14 (n = 5 per treatment arm). Serial assessments of basal reproductive hormones, ultrasound parameters, LH pulsatility, and acute sensitivity to GnRH and kisspeptin-54 injection were performed. Results: Menstrual cyclicity persisted in all women after follicular-phase kisspeptin-54 treatment. Chronic exposure to kisspeptin-54 did not abolish acute stimulation of LH after injection of kisspeptin-54 or GnRH. In addition, kisspeptin-54 treatment was associated with a shorter mean length of the menstrual cycle (mean length of menstrual cycle was 28.6 ± 1.4 days with saline vs 26.8 ± 3.1 days with kisspeptin, P < .01), earlier onset of highest recorded serum LH (mean menstrual day of highest LH was 15.2 ± 1.3 with saline vs 13.0 ± 1.9 with kisspeptin, P < .05), and earlier onset of the luteal phase (mean menstrual day of progesterone increase was 18.0 ± 2.1 with saline vs 15.8 ± 0.9 with kisspeptin, P < .05). Conclusion: Our data suggest that 1 week of exogenous kisspeptin-54 does not abolish menstrual cyclicity in healthy women. Further work is needed to determine whether kisspeptin could be used to treat certain anovulatory disorders.


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