scholarly journals Androgens and the male reproductive tract: an overview of classical roles and current perspectives

2009 ◽  
Vol 53 (8) ◽  
pp. 934-945 ◽  
Author(s):  
Marilia T. C. C. Patrão ◽  
Erick J. R. Silva ◽  
Maria Christina W. Avellar

Androgens are steroid hormones that play key roles in the development and maintenance of male phenotype and reproductive function. These hormones also affect the function of several non-reproductive organs, such as bone and skeletal muscle. Endogenous androgens exert most of their effects by genomic mechanisms, which involve hormone binding to the androgen receptor (AR), a ligand-activated transcription factor, resulting in the modulation of gene expression. AR-induced non-genomic mechanisms have also been reported. A large number of steroidal and non-steroidal AR-ligands have been developed for therapeutic use, including the treatment of male hypogonadism (AR agonists) and prostate diseases (AR antagonists), among other pathological conditions. Here, the AR gene and protein structure, mechanism of action and AR gene homologous regulation were reviewed. The AR expression pattern, its in vivo regulation and physiological relevance in the developing and adult testis and epididymis, which are sites of sperm production and maturation, respectively, were also presented.

1984 ◽  
Vol 32 (6) ◽  
pp. 721 ◽  
Author(s):  
H Marsh ◽  
GE Heinsohn ◽  
TD Glover

The anatomy and histology of the male reproductive tract of the dugong (Dugong dugon) is described. Each testis and its adjacent epididymis lie immediately caudal to the corresponding kidney. The seminal vesicles are large but there is no discrete prostate gland and the bulbo-urethral glands are also diffuse. Both qualitative and quantitative examination of the testes and epididymides of 59 males whose ages have been estimated from tusk dentinal growth layer counts indicate that the male dugong does not produce spermatozoa continuously, despite the absence of a distinct breeding season. Individual dugongs were observed with testes at all stages between complete quiescence and full spermatogenesis, and only 10 of the 40 mature males had fully spermatogenic testes and epididymides packed with spermatozoa. Androgenic and spermatogenic activity of the testes appeared to be in phase, but the testicular histology of some old males suggested that they may have been sterile for long periods.


2002 ◽  
Vol 56 (1-2) ◽  
pp. 105-110
Author(s):  
Radoslav Dosen ◽  
Mladen Gagrcin ◽  
Jasna Prodanov

In this paper we examined the effects of certain pathological conditions on the sterility of breeding sows. Pathomorphological investigations were performed on 185 reproductive organs. We analyzed the reasons for elimination from local records. The biggest number of sows with pathological changes on reproductive organs were in the group of barren sows, 48.68% followed by anestric sows, 30.26%, and the smallest number in sows with failed fertilizations, 21.05%. Cysts in ovaries, ovarian tubes, oviducts and ?the mesosalpinx were found in 23.77% of the examined sows. Lutein cysts were found in a significantly higher percentage in sows which fail to be fertilized than in barren or anestric animals. Small granular degeneration of the ovaries was determined in barren sows and those which cannot be fertilized, while it was not determined in anestric sows. Cysts on uterus ligaments and ovaries and on ovarian tubes and oviducts were found in significantly higher numbers in sows which fail be fertilized than in barren or anestric sows. Their presence can be connected to obstructions in the transport process of spermatozoa, eggs, and the fertilization process in sows which fail to be fertilized, especially in cases of cysts located on the very serosa of ovarian tubes which we found in these sows. We determined small granular degeneration of the ovaries in barren sows and those which fail to fertilized, but not in anestric sows. Ovarian insufficiency was mostly connected to anestric sows. Vaginitis, endometritis, periometritis and oocytis present an important factor in the occurrence of sterility primarily in sows which are barren or which fail to be fertilized.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Yusuf Abba ◽  
Suleiman Simon ◽  
Halima Idris Gambo ◽  
Ikechukwu Onyebuchi Igbokwe ◽  
Yusuf Iliyasu

The study of pathological conditions of the male reproductive system is paramount to understanding reproductive inefficiency in the Sahel goat. In this study, 1048 Sahel bucks presented for slaughter at the Maiduguri metropolitan abattoir were evaluated for the presence of various pathological abnormalities of the reproductive system. A total incidence of 15.08% was recorded for various pathological conditions, with testicular, penile, and scrotal conditions having incidences of 7.82%, 4.80 and 2.50%, respectively. Bilateral testicular hypoplasia and atrophy and unilateral cryptorchidism accounted for incidences of 4.10%, 2.38%, and 1.24%, respectively, while paraphimosis and scrotal laceration had incidences of 1.72% and 1.05%, respectively. Age specific incidence of pathological conditions were not significant(P>0.05)between bucks aged <1–1.5 and 2–2.5 years. However, bucks aged 3–3.5 year a had lower(P<0.05)incidence of pathological conditions than other age groups. Histopathological evidence of inflammation, degeneration, and atrophy was observed in the testes, while inflammatory changes were observed in the prepuce.


Author(s):  
S. K. Bhure ◽  
P. Harikrishna ◽  
J. Usharani ◽  
A. M. Shende ◽  
S. Harikumar

Regucalcin is a multifunctional protein having an important role in calcium homeostasis, L-ascorbic acid biosynthesis, anti-prolific, anti-apoptotic functions as well as detoxification of chemical warfare nerve agents. Recently, it has been localized to male reproductive tract of rat and human, and identified as an androgen-target gene. The literature suggests a possible role of regucalcin in male fertility. However, no detailed studies have been conducted on its role in male reproductive organs of domestic animals. As an initial step, we had cloned and expressed regucalcin in Pichia pastoris. The sequence analysis showed 100% homology with regucalcin of Bos tours both at nucleotide and amino acid level. The SDS-PAGE and Western blot studies of recombinant protein probed with anti-regucalcin monoclonal antibody showed a higher molecular weight (56 kDa) than the expected (35.5 kDa) that could be due to hyperglycosylation. The recombinant regucalcin and its antibodies can be used to study the detailed role of the protein in male reproduction.


Reproduction ◽  
2013 ◽  
Vol 146 (3) ◽  
pp. 283-296 ◽  
Author(s):  
Hyun-Wook Lee ◽  
Jill W Verlander ◽  
Mary E Handlogten ◽  
Ki-Hwan Han ◽  
Paul S Cooke ◽  
...  

The rhesus glycoproteins, Rh B glycoprotein (RHBG) and Rh C glycoprotein (RHCG), are recently identified ammonia transporters. Rhcg expression is necessary for normal male fertility, but its specific cellular expression is unknown, and Rhbg has not been reported to be expressed in the male reproductive tract. This study sought to determine the specific cellular expression of Rhcg, to determine whether Rhbg is expressed in the male reproductive tract, and, if so, to determine which cells express Rhbg using real-time RT-PCR, immunoblot analysis, and immunohistochemistry. Both Rhbg and Rhcg were expressed throughout the male reproductive tract. In the testis, high levels of Rhbg were expressed in Leydig cells, and Rhcg was expressed in spermatids during the later stages of their maturation (steps 13–16) in stages I–VIII of the seminiferous epithelium cycle. In the epididymis, basolateral Rhbg was present in narrow cells in the initial segment, in principal cells in the upper corpus, and in clear cells throughout the epididymis. Apical Rhcg immunolabel was present in principal cells in the caput and upper corpus epididymidis and in clear cells in the middle and lower corpus and cauda epididymidis. In the vas deferens, apical Rhcg immunolabel and basolateral Rhbg immunolabel were present in some principal cells and colocalized with H+-ATPase immunolabel. We conclude that both Rhbg and Rhcg are highly expressed in specific cells in the male reproductive tract where they can contribute to multiple components of male fertility.


Author(s):  
Golden Gokhale ◽  
Pir Mohammad Ishfaq ◽  
Gurudutt Sharma

The nutritional, physiological, and reproductive function has detrimental effects on heat stress, which is found in many species of mammals. High ambient temperature in mammals cause a decrease in the length and intensity of estrus by disturbing ovarian function as well as decreasing pregnancy rate after artificial insemination. The effects of nutritional stress on developing oocytes in the ovarian follicle and in the reproductive tract on early embryos are because of the environment where a breeding female lives before conception and at the early stages of pregnancy. Maturity of oocyte, blastocyst yield, prenatal survival, and the number of offspring born alive are affected by change in consumption and quantity of the food taken during the pre-mating period. To improve reproductive efficiency and offspring quality, it is necessary to detect and evaluate the deteriorating effects of heat stress on reproductive organs and cells and to plan nutrition related strategies.


2020 ◽  
Vol 103 (2) ◽  
pp. 183-194
Author(s):  
Jiang Sun ◽  
Yonggang Lu ◽  
Kaori Nozawa ◽  
Zoulan Xu ◽  
Akane Morohoshi ◽  
...  

Abstract Developing a safe and effective male contraceptive remains a challenge in the field of medical science. Molecules that selectively target the male reproductive tract and whose targets are indispensable for male reproductive function serve among the best candidates for a novel non-hormonal male contraceptive method. To determine the function of these genes in vivo, mutant mice carrying disrupted testis- or epididymis-enriched genes were generated by zygote microinjection or electroporation of the CRISPR/Cas9 components. Male fecundity was determined by consecutively pairing knockout males with wild-type females and comparing the fecundity of wild-type controls. Phenotypic analyses of testis appearance and weight, testis and epididymis histology, and sperm movement were further carried out to examine any potential spermatogenic or sperm maturation defect in mutant males. In this study, we uncovered 13 testis- or epididymis-enriched evolutionarily conserved genes that are individually dispensable for male fertility in mice. Owing to their dispensable nature, it is not feasible to use these targets for the development of a male contraceptive.


2020 ◽  
pp. 13-19

Introduction: Slaughtering of pregnant animals resulting in foetal wastages abound in many countries of the world. The practice of slaughtering of gravid animals in Nigeria is largely due to lower economic standards of the citizens. This study was to establish the nature and incidence of reproductive abnormalities and foetal wastages in small ruminants observed at Dogarawa slaughter slab Zaria, Kaduna state. Methods: Ante-mortem and post-mortem examinations of the genital tract of slaughtered small ruminants were conducted using visual examination, palpation and incision. A total of 1695 animals slaughtered on weekends (Saturdays and Sundays) within the months of August and September 2019 were examined. A total of 1158 bucks, 264 does, 111 ewes and 162 rams were slaughtered. Values obtained were presented in percentages using Microsoft excel, 2016. Results: A total of 52 foetal wastages were recorded (71.15% in sheep and 28.85% in goats). Abnormalities of the ovaries observed include ovarian hypertrophy (6.25%), the cystic follicle (12.5%) and unilateral ovarian agenesis (6.25%), which were detected at post-mortem examination. Abnormalities of the uterus observed were pyometra (6.25%), hydrometra (6.25%), metritis (12.5%) and uterine atrophy (6.25%). Supernumerary teats (25%) and mastitis (18.75%) were also observed. Ante-mortem and post-mortem gross pathological conditions of the male reproductive tract revealed; cryptorchidism (41.18%), paraphimosis (11.26%), testicular hypoplasia (5.88%), epididymitis (29.41%) and balanoposthitis (11.76%). Significance: The results from this study revealed various types of reproductive anomalies in animals brought to slaughter. The study also revealed the practice of slaughtering of pregnant animals resulting in foetal wastages.


Zygote ◽  
2010 ◽  
Vol 19 (4) ◽  
pp. 287-295 ◽  
Author(s):  
Pedro Esponda

SummaryThis review summarizes the results of research on gene transfer to the mammalian genital tract. Gene transfer experiments have been developed during the last 2 decades and have been applied using in vitro, ex vivo and in vivo procedures. (i) In vitro methods have been applied to the uterine epithelial cells with the principal purpose of analysing some pathological change occurring in the uterus. In the male tract, epididymal cell lines have been used to evaluate the expression of particular genes and the function of specific proteins. (ii) Ex vivo methods have been applied to both the uterus and the vas deferens in humans, and good transgene expression has been recorded. (iii) In vivo gene transfer in the female tract has been employed in the uterus and oviduct using gene injections or electroporation methods. The glandular epithelium of both organs can be transfected efficiently, and transfection efficiency depends on the hormonal stage of the animal. The best expression occurred during pseudopregnancy and meta-estrus periods, when high progesterone and low estradiol concentrations occur. In the male tract, in vivo methods have been applied to mouse vas deferens and epididymis. In both organs, patches of epithelial regions appeared to express the transgenes. Furthermore, the secretions of both organs were also modified using gene constructions that led to the expression of some secretory proteins. In summary, gene modifications in the epithelium of the mammalian reproductive tract have been successful employing different technologies. Further improvements in transfection efficiency would help provide new insights into the physiology of these reproductive organs. Furthermore, the use of these methods could also be used to modify the fertility of mammals.


Endocrinology ◽  
2009 ◽  
Vol 150 (6) ◽  
pp. 2898-2905 ◽  
Author(s):  
Kerstin W. Sinkevicius ◽  
Muriel Laine ◽  
Tamara L. Lotan ◽  
Karolina Woloszyn ◽  
John H. Richburg ◽  
...  

Estrogen receptor-α (ERα) plays a critical role in male reproductive tract development and fertility. To determine whether estrogen-dependent and -independent ERα mechanisms are involved in male fertility, we examined male estrogen nonresponsive ERα knock-in mice. These animals have a point mutation (G525L) in the ligand-binding domain of ERα that significantly reduces interaction with, and response to, endogenous estrogens but does not affect growth factor activation of ligand-independent ERα pathways. Surprisingly, we found that ligand-independent ERα signaling is essential for concentrating epididymal sperm via regulation of efferent ductule fluid reabsorption. In contrast, estrogen-dependent ERα signaling is required for germ cell viability, most likely through support of Sertoli cell function. By treating estrogen nonresponsive ERα knock-in (ENERKI) mice with the ERα selective synthetic agonist propyl pyrazole triol, which is able to bind and activate G525L ERα in vivo, we discovered male fertility required neonatal estrogen-mediated ERα signaling. Thus, our work indicates both estrogen-dependent and -independent pathways play separable roles in male murine reproductive tract development and that the role of ERα in human infertility should be examined more closely.


Sign in / Sign up

Export Citation Format

Share Document