5 TESTICULAR GnRH-II RECEPTOR KNOCKDOWN IMPAIRS DIURNAL TESTOSTERONE SECRETION IN THE BOAR

2017 ◽  
Vol 29 (1) ◽  
pp. 110
Author(s):  
A. T. Desaulniers ◽  
R. A. Cederberg ◽  
C. A. Lents ◽  
B. R. White
Keyword(s):  
Fixed Effects ◽  
Leydig Cells ◽  
Pubertal Development ◽  
Critical Role ◽  
Serum Testosterone ◽  
Male Reproductive Success ◽  
Testis Weight ◽  
Mrna Levels ◽  
Littermate Control ◽  
Time Interaction

The second mammalian GnRH isoform (GnRH-II) and its specific receptor (GnRHR-II) are ubiquitously expressed, with elevated levels in the testis. Gene coding errors prevent their production in many species, but both genes are functional in swine. We demonstrated that GnRHR-II localizes to porcine Leydig cells, and exogenous GnRH-II robustly stimulates testosterone production in vivo, despite minimal luteinizing hormone (LH) secretion. These data suggest that GnRH-II directly effects steroidogenesis in the boar testis. To explore this hypothesis, we produced a GnRHR-II knockdown (KD) swine line. Upon characterisation of this line, serum testosterone concentrations were reduced in GnRHR-II KD compared with littermate control males during pubertal development. However, concentrations of LH were unaffected, indicating that GnRHR-II KD impairs steroidogenesis directly at the testis rather than inhibiting gonadotropin secretion from the anterior pituitary gland. Based on these results, the objective of this study was to compare diurnal secretory patterns of testosterone in mature GnRHR-II KD (n = 5) and littermate control (n = 5) males. Boars were fit with indwelling jugular cannulae and blood was collected every 15 min for 8 h. Serum was assayed for testosterone concentration via radioimmunoassay. Next, GnRHR-II KD (n = 5) and littermate control (n = 4) boars were killed, testis weight was recorded, and testicular tissue was collected for RNA isolation. To confirm KD in these animals, digital droplet PCR was performed to quantify GnRHR-II mRNA abundance (normalized to β-actin). Data were analysed using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC, USA) with line (transgenic or control) as the fixed effect and litter as a random effect. For hormone data, time and line × time interaction were included as fixed effects, with time as a repeated measure. Although there was no effect of time or line × time interaction (P > 0.05) on serum testosterone concentrations, we observed a line effect (P < 0.05). Differences between lines were dramatic; testosterone was reduced by 82% in GnRHR-II KD (0.75 ± 0.05 ng mL−1) compared with littermate control (4.09 ± 0.29 ng mL−1; P < 0.05) males. Despite divergent testosterone levels, testis weights were similar between lines (P > 0.05) indicative of altered Leydig cell function as opposed to hypertrophy/hyperplasia. Given that testicular GnRHR-II mRNA levels were reduced by 69% in transgenic animals (P < 0.001), these data demonstrate that GnRH-II and its receptor play a critical role in testosterone biosynthesis within porcine Leydig cells. Thus, this report reveals novel mediators of testicular function in the boar and challenges the central dogma of testosterone regulation. Because testosterone dictates male reproductive success, GnRH-II and its receptor represent unique targets to improve fertility in swine. This study was partially supported by NIFA Hatch (NEB-26-199; BRW) and AFRI (2011-67015; CAL) funds.

scholarly journals Evaluation of relative roles of LH and FSH in regulation of differentiation of Leydig cells using an ethane 1,2-dimethylsulfonate-treated adult rat model

2003 ◽  
Vol 176 (1) ◽  
pp. 151-161 ◽  
Author(s):  
V Sriraman ◽  
MR Sairam ◽  
AJ Rao
Keyword(s):  
Leydig Cells ◽  
Serum Testosterone ◽  
Side Chain ◽  
Mrna Levels ◽  
Rt Pcr ◽  
Lh Receptor ◽  
Side Chain Cleavage ◽  
Chain Cleavage ◽  
Cleavage Enzyme

The relative role of LH and FSH in regulation of differentiation of Leydig cells was assessed using an ethane 1,2-dimethylsulfonate (EDS)-treated rat model in which endogenous LH or FSH was neutralized from day 3 to day 22 following EDS treatment. Serum testosterone and the in vitro response of the purified Leydig cells to human chorionic gonadotropin (hCG) was monitored. In addition RNA was isolated from the Leydig cells to monitor the steady-state mRNA levels by RT-PCR for 17alpha-hydroxylase, side chain cleavage enzyme, steroidogenic acute regulatory protein (StAR), LH receptor, estrogen receptor (ER-alpha) and cyclophilin (internal control). Serum testosterone was undetected and the isolated Leydig cells secreted negligible amount of testosterone on stimulation with hCG in the group of rats that were treated with LH antiserum following EDS treatment. RT-PCR analysis revealed the absence of message for cholesterol side chain cleavage enzyme and 17alpha-hydroxylase although ER-alpha and LH receptor mRNA could be detected, indicating the presence of undifferentiated precursor Leydig cells. In contrast, the effects following deprival of endogenous FSH were not as drastic as seen following LH neutralization. Deprival of endogenous FSH in EDS-treated rats led to a significant decrease in serum testosterone and in vitro response to hCG by the Leydig cells. Also, there was a significant decrease in the steady-state mRNA levels of 17alpha-hydroxylase, cholesterol side chain cleavage enzyme, LH receptor and StAR as assessed by a semiquantitative RT-PCR. These results establish that while LH is obligatory for the functional differentiation of Leydig cells, repopulation of precursor Leydig cells is independent of LH, and also unequivocally establish an important role for FSH in regulation of Leydig cell function.

scholarly journals Comparison of cell types in the rat Leydig cell lineage after ethane dimethanesulfonate treatment

Reproduction ◽  
2013 ◽  
Vol 145 (4) ◽  
pp. 371-380 ◽  
Author(s):  
Jingjing Guo ◽  
Hongyu Zhou ◽  
Zhijian Su ◽  
Bingbing Chen ◽  
Guimin Wang ◽  
...  
Keyword(s):  
Leydig Cell ◽  
Leydig Cells ◽  
Pubertal Development ◽  
Cell Lineage ◽  
Hydroxysteroid Dehydrogenase ◽  
Mrna Levels ◽  
Steroidogenic Enzymes ◽  
Isolated Cells ◽  
Adult Leydig Cells

The objective of this study was to purify cells in the Leydig cell lineage following regeneration after ethane dimethanesulfonate (EDS) treatment and compare their steroidogenic capacity. Regenerated progenitor (RPLCs), immature (RILCs), and adult Leydig cells (RALCs) were isolated from testes 21, 28 and 56 days after EDS treatment respectively. Production rates for androgens including androsterone and 5α-androstane-17β, 3α-diol (DIOL), testosterone and androstenedione were measured in RPLCs, RILCs and RALCs in media after 3-h in vitro culture with 100 ng/ml LH. Steady-state mRNA levels of steroidogenic enzymes and their activities were measured in freshly isolated cells. Compared to adult Leydig cells (ALCs) isolated from normal 90-day-old rat testes, which primarily produce testosterone (69.73%), RPLCs and RILCs primarily produced androsterone (70.21%) and DIOL (69.79%) respectively. Leydig cells isolated from testes 56 days post-EDS showed equivalent capacity of steroidogenesis to ALCs and primarily produced testosterone (72.90%). RPLCs had cholesterol side-chain cleavage enzyme, 3β-hydroxysteroid dehydrogenase 1 and 17α-hydroxylase but had almost no detectable 17β-hydroxysteroid dehydrogenase 3 and 11β-hydroxysteroid dehydrogenase 1 activities, while RILCs had increased 17β-hydroxysteroid dehydrogenase 3 and 11β-hydroxysteroid dehydrogenase 1 activities. Because RPLCs and RILCs had higher 5α-reductase 1 and 3α-hydroxysteroid dehydrogenase activities they produced mainly 5α-reduced androgens. Real-time PCR confirmed the similar trends for the expressions of these steroidogenic enzymes. In conclusion, the purified RPLCs, RILCs and RALCs are similar to those of their counterparts during rat pubertal development.

Leydig cell resistance to the cytotoxic effect of ethylene dimethanesulphonate in the adult rat testis

1985 ◽  
Vol 105 (3) ◽  
pp. 311-NP ◽  
Author(s):  
I. D. Morris
Keyword(s):  
Seminal Vesicle ◽  
Leydig Cell ◽  
Leydig Cells ◽  
Serum Testosterone ◽  
Male Rats ◽  
Cell Physiology ◽  
Testis Weight ◽  
Endocrine Activity ◽  
Adult Rat ◽  
Seminal Vesicle Weight

ABSTRACT Weekly doses of the Leydig cell cytotoxic ethylene dimethanesulphonate (EDS) were administered to adult male rats in an attempt to study the endocrine activity of the testis in the absence of Leydig cells. One week after the first dose serum testosterone and LH concentrations and seminal vesicle weights were close to levels in castrated rats and testicular human chorionic gonadotrophin (hCG) binding was severely depressed. These changes were maintained for a further week but subsequently began to return to, but did not achieve, control levels. After six weekly doses seminal vesicle weight and serum testosterone concentrations were significantly higher than in the castrated rats. Serum LH concentrations were declining towards control values at 4 weeks but had risen again at 6 weeks. Serum FSH concentrations were raised to about 50% of the value in castrated rats throughout the period studied. Testis weight and hCG binding, which initially fell, were partially restored at 6 weeks and spermatogenesis was recovering. The data show that responses of the testis to multiple doses of EDS are similar to those after a single dose. This apparent resistance indicates that the regenerating Leydig cells are functionally different from the mature Leydig cell. The similarities between the maturing Leydig cell seen after EDS destruction and those in the immature rat suggest that EDS will provide a valuable model for the investigation of Leydig cell physiology. J. Endocr. (1985) 105, 311–316

scholarly journals Deletion of Nuclear Receptor Constitutive Androstane Receptor CAR Increases Anxiety and Lowers Androgen Levels

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A807-A807
Author(s):  
Juan P Hernandez ◽  
Anjana Asokakumar ◽  
Rui Xiao ◽  
David D Moore ◽  
Sayeepriyadarshini Anakk
Keyword(s):  
Nuclear Receptor ◽  
Leydig Cells ◽  
Constitutive Androstane Receptor ◽  
Serum Testosterone ◽  
Transcriptional Networks ◽  
Testis Weight ◽  
Orphan Nuclear Receptor ◽  
Plus Maze ◽  
Marble Burying ◽  
Androgen Levels

Abstract The orphan nuclear receptor, Constitutive Androstane Receptor (CAR, NR1I3) is primarily known to regulate the transcriptional networks involved in detoxification. We have identified a novel extra-hepatic role of CAR in regulating androgen levels and modulating testis function. Previous data has revealed that CAR activation by estradiol and inactivation by androstanol suggests an intricate link between sex hormones and CAR. We investigated control wild type and CARKO mice and found that the serum testosterone and androstenedione levels were lower in the absence of CAR. As expected, we did not find any induction of the genes in the detoxification machinery including, Cyp3a, Cyp2b, Cyp2c family, Sult2a1 and Mrp. The decrease in the androgen levels in the CARKO mice is consistent with decrease in the anogenital distance, increased anxiety as measured by marble burying and elevated plus maze but no change in testis weight. H&E staining of CARKO mice shows accumulation of fat in the Leydig cells and lower numbers of Leydig cells which are in accordance with the loss of androgen levels. In addition, we will examine the consequence of reduced androgen and the hypothalamus-pituitary-gonadal axis in the CARKO mice.

scholarly journals Leydig Cells Express Follicle-Stimulating Hormone Receptors in African Catfish

Endocrinology ◽  
2008 ◽  
Vol 150 (1) ◽  
pp. 357-365 ◽  
Author(s):  
Ángel García-López ◽  
Jan Bogerd ◽  
Joke C. M. Granneman ◽  
Wytske van Dijk ◽  
John M. Trant ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Protein Kinase A ◽  
Leydig Cells ◽  
Hormone Receptors ◽  
Pubertal Development ◽  
Clarias Gariepinus ◽  
Receptor Expression ◽  
African Catfish ◽  
Testis Weight ◽  
Kinase A

This report aimed to establish, using African catfish, Clarias gariepinus, as model species, a basis for understanding a well-known, although not yet clarified, feature of male fish reproductive physiology: the strong steroidogenic activity of FSHs. Assays with gonadotropin receptor-expressing cell lines showed that FSH activated its cognate receptor (FSHR) with an at least 1000-fold lower EC50 than when challenging the LH receptor (LHR), whereas LH stimulated both receptors with similar EC50s. In androgen release bioassays, FSH elicited a significant response at lower concentrations than those required to cross-activate of the LHR, indicating that FSH stimulated steroid release via FSHR-dependent mechanisms. LHR/FSHR-mediated stimulation of androgen release was completely abolished by H-89, a specific protein kinase A inhibitor, pointing to the cAMP/protein kinase A pathway as the main route for both LH- and FSH-stimulated steroid release. Localization studies showed that intratubular Sertoli cells express FSHR mRNA, whereas, as reported for the first time in a vertebrate, catfish Leydig cells express both LHR and FSHR mRNA. Testicular FSHR and LHR mRNA expression increased gradually during pubertal development. FSHR, but not LHR, transcript levels continued to rise between completion of the first wave of spermatogenesis at about 7 months and full maturity at about 12 months of age, which was associated with a previously recorded approximately 3-fold increase in the steroid production capacity per unit testis weight. Taken together, our data strongly suggest that the steroidogenic potency of FSH can be explained by its direct trophic action on FSHR-expressing Leydig cells. In search of a mechanistic basis for the strong steroidogenic activity of fish FSH, we demonstrate FSH receptor expression by Leydig cells in catfish.

scholarly journals Selenium Requirements Are Higher for Glutathione Peroxidase-1 mRNA than Gpx1 Activity in Rat Testis

2009 ◽  
Vol 234 (5) ◽  
pp. 513-521 ◽  
Author(s):  
Sonja C. Schriever ◽  
Kimberly M. Barnes ◽  
Jacqueline K. Evenson ◽  
Anna M. Raines ◽  
Roger A. Sunde
Keyword(s):  
Glutathione Peroxidase ◽  
Critical Role ◽  
Cell Types ◽  
Pcr Analysis ◽  
Testis Weight ◽  
Mrna Levels ◽  
Response Curves ◽  
Lower Priority ◽  
Selenoprotein Mrnas ◽  
Se Status

Selenium (Se) plays a critical role in testis, sperm, and reproduction, and testis Se levels are remarkably maintained in Se deficiency. In most other tissues, Se levels decrease dramatically as do levels of most selenoproteins and levels of a subset of Se-regulated selenoprotein mRNAs. Because of the recent identification of key molecules in the targeted trafficking of Se to the testis, we examined the hierarchy of Se regulation in testis by determining the dietary Se regulation of the full testis selenoproteome in rats fed graded levels of Se (0 to 0.8 μg Se/g) as Na2SeO3 for 28 d. Se status did not significantly affect testis weight or glutathione peroxidase 4 (Gpx4) activity ( P > 0.05). qRT-PCR analysis of selenoprotein mRNA expression revealed that 21 of the 24 selenoprotein mRNAs and ApoER2 mRNA (the selenoprotein P [Sepp1] receptor) were also not regulated significantly by dietary Se status. In contrast, Gpx1 activity decreased to 28% of Se-adequate levels, and mRNA levels for Gpx1, Sepp1, and Sepw1 (selenoprotein W) decreased significantly in Se-deficient rats to 45, 46, and 55%, respectively, of Se-adequate plateau levels. Overlap of hyperbolic Gpx4 activity and Sepw1 mRNA response curves with testis Se concentration, all with minimum dietary Se requirements <0.016 μg Se/g, showed the priority for synthesis of Gpx4. Higher minimum dietary Se requirements of 0.04 μg Se/g for Gpx1 activity and Sepp1 mRNA, and the even higher minimum dietary Se requirement of 0.08 μg Se/g for Gpx1 mRNA, suggest that the hierarchy of these biomarkers reflects distinct, lower priority pools, cell types, and roles for Se within the testis.

scholarly journals Mediterranean Diet, Screen-Time-Based Sedentary Behavior and Their Interaction Effect on Adiposity in European Adolescents: The HELENA Study

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 474
Author(s):  
Miguel Seral-Cortes ◽  
Sergio Sabroso-Lasa ◽  
Alexandro Bailo-Aysa ◽  
Marcela Gonzalez-Gross ◽  
Dénes Molnár ◽  
...  
Keyword(s):  
Childhood Obesity ◽  
Mediterranean Diet ◽  
Screen Time ◽  
Sedentary Time ◽  
Pubertal Development ◽  
Female Adolescents ◽  
Fat Mass Index ◽  
Time Interaction ◽  
Sedentary Behaviours ◽  
Helena Study

Childhood obesity is a worldwide epidemic. Mediterranean diet (MD) is inversely associated with childhood obesity, but the interaction with other environmental factors, such screen time, might influence the health benefits of a high MD adherence in adolescents. The aim of the present study was to assess whether an association between MD and screen time exists in European adolescents. Moreover, we also explored whether sedentary time has a modulatory effect on the association between MD and adiposity. Adherence to the MD (24 h recalls), screen time (questionnaire), pubertal development, body mass index (BMI), fat mass index (FMI) and waist circumference (WC) were evaluated in 2053 adolescents (54.7% females), aged 12.5–17.5 years. In females, MD adherence was associated with lower BMI and FMI only when they were exposed to less than 338 min/day of screen time (81.8% of females); MD adherence was also associated with lower WC only when females were exposed to less than 143 min/day of screen time (31.5% of females). No significant MD-screen time interaction was observed in males. In conclusion, screen-time-based sedentary behaviours had a modulatory effect in the association between MD adherence and adiposity in European female adolescents.

Abstract 101: Tissue-specific Deletion of Collectrin in the Proximal Tubular Epithelium Increases Arterial Pressure and Augments Salt-sensitivity

Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Sylvia Cechova ◽  
Pei-Lun Chu ◽  
Joseph C Gigliotti ◽  
Fan Chan ◽  
Thu H Le
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Renal Blood Flow ◽  
Collecting Duct ◽  
Critical Role ◽  
Specific Effect ◽  
Salt Sensitivity ◽  
Kidney Cortex ◽  
Mrna Levels ◽  
Proximal Tubular

Background: Collectrin ( Tmem27 ) is a key regulator of blood pressure (BP) and modulator of the bioavailability of nitric oxide (NO) and superoxide. It is highly expressed in the kidney in the proximal tubule (PT), collecting duct, and throughout the vascular endothelium. We reported that collectrin plays a critical role as a chaperone for the reabsorption of all amino acids (AAs) in the PT, and for the uptake of the cationic AA L-arginine (L-Arg) in endothelial cells. Global collectrin knockout ( Tmem27 Y/- ) mice display baseline hypertension (HTN), augmented salt-sensitive hypertension (SSH), and decreased renal blood flow. Objective and Methods: To determine the PT-specific effect of collectrin on BP homeostasis and salt sensitivity, we used the Cre -loxP approach and PEPCK-Cre to generate a mouse line lacking collectrin specifically in the PT-- PEPCK-Cre + Tmem27 Y/Flox mice. PEPCK-Cre - Tmem27 Y/Flox mice were used as control. Radiotelemetry was used to measure BP for 2 weeks at baseline and 2 weeks on high salt diet (HSD). Renal blood flow at baseline and on HSD was measured using contrast enhanced ultrasound in the same mice. Results: Successful deletion of collectrin in the PT was confirmed by assessing mRNA levels using real-time RT-PCR, immunohistochemistry staining of renal tissues using anti-collectrin antibody, and quantitation of protein from kidney cortex by Western analysis. Compared to control PEPCK-Cre - Tmem27 Y/Flox mice (n=6), PEPCK-Cre + Tmem27 Y/Flox mice (n=6) displayed significantly higher systolic BP (SBP) at baseline (120.0 ± 2.5 vs 131.6 ± 2.9 mm Hg; p = 0.014) and after HSD (135.3 ± 2.6 vs 151.5 ± 5.2 mm Hg; p = 0.019). Renal blood flow was not different between groups, at baseline nor after HSD. Conclusion: Collectrin in the PT plays an important role in blood pressure homeostasis and response to sodium intake, independent of renal blood flow. Increasing proximal tubular collectrin activity may be a novel therapeutic strategy for the treatment of hypertension and salt-sensitivity.

Vitamin C ameliorates the adverse effects of dexamethasone on sperm motility, testosterone level, and spermatogenesis indexes in mice

2018 ◽  
Vol 38 (4) ◽  
pp. 409-418 ◽  
Author(s):  
F Sadeghzadeh ◽  
MS Mehranjani ◽  
M Mahmoodi
Keyword(s):  
Adverse Effects ◽  
Vitamin C ◽  
Sperm Motility ◽  
Testosterone Level ◽  
Leydig Cells ◽  
Serum Testosterone ◽  
Serum Testosterone Level ◽  
Control Group ◽  
The Mean ◽  
Vit C

Background: Dexamethasone (DEX) is a common medicine that is capable of causing malformation in the male reproductive system. The aim of this study was to investigate the effect of vitamin C (Vit-C) on spermatogenesis indexes and daily sperm production (DSP) in adult mice treated with DEX. Methods: Male Naval Medical Research Institute (NMRI) mice were divided into four groups: Control, DEX (7 mg/kg/day), Vit-C (100 mg/kg/day), and DEX +Vit-C and treated for 7 days with intraperitoneal injection. Results: A significant increase in the mean levels of serum and tissue malondialdehyde (MDA) and apoptosis of Leydig cells was found in the DEX group compared to the control group. Sperm motility, DSP, tubular differentiation index, meiotic index, spermatogenesis index, the mean number of spermatocytes, round and long spermatids, and Leydig cells, and also serum testosterone level decreased in the DEX group compared to the control group. The results of this study indicate that Vit-C can significantly prevent the adverse effects of DEX on the mean number of spermatocyte, spermatid, and Leydig cells, tubular differentiation, meiotic and spermatogenesis index, DSP, sperm motility, and the mean levels of serum MDA. Conclusion: In conclusion, our results showed that coadministration of Vit-C and DEX prevents the adverse effects of DEX on the spermatogenesis indexes and DSP.

Inhibitory Effect of Tributyltin on Expression of Steroidogenic Enzymes in Mouse Testis

2008 ◽  
Vol 27 (2) ◽  
pp. 175-182 ◽  
Author(s):  
Suel-Kee Kim ◽  
Jong-Hoon Kim ◽  
Jung Ho Han ◽  
Yong-Dal Yoon
Keyword(s):  
Germ Cells ◽  
Leydig Cells ◽  
Serum Testosterone ◽  
Hydroxysteroid Dehydrogenase ◽  
Reproductive Organs ◽  
Inhibitory Effect ◽  
Testicular Development ◽  
Steroidogenic Enzymes ◽  
Hormone Production ◽  
Induced Apoptosis

Tributyltin (TBT) is known to disrupt the development of reproductive organs, thereby reducing fertility. The aim of this study was to evaluate the acute toxicity of TBT on the testicular development and steroid hormone production. Immature (3-week-old) male mice were given a single administration of 25, 50, or 100 mg/kg of TBT by oral gavage. Lumen formation in seminiferous tubule was remarkably delayed, and the number of apoptotic germ cells found inside the tubules was increased in the TBT-exposed animals, whereas no apoptotic signal was observed in interstitial Leydig cells. Reduced serum testosterone concentration and down-regulated expressions of the mRNAs for cholesterol side-chain cleavage enzyme (P450scc), 17α-hydroxylase/C17–20 lyase (P45017α), 3β-hydroxysteroid-dehydrogenase (3β-HSD), and 17β-hydroxysteroid-dehydrogenase (17β-HSD) were also observed after TBT exposure. Altogether, these findings demonstrate that exposure to TBT is associated with induced apoptosis of testicular germ cells and inhibition of steroidogenesis by reduction in the expression of steroidogenic enzymes in interstitial Leydig cells. These adverse effects of TBT would cause serious defects in testicular development and function.

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