255. Hormonal manipulation on the phenotype of ArKO female mice

2008 ◽  
Vol 20 (9) ◽  
pp. 55
Author(s):  
S. H. Liew ◽  
A. E. Drummond ◽  
J. E. Margaret ◽  
J. K. Findlay

Gonadotrophins and steroid hormones are vital in controlling the cyclical pattern of ovarian follicular development essential for fertility. Previous studies have shown that ArKO (aromatase knockout) female mice are infertile due to the absence of oestrogen, elevated levels of circulating gonadotrophins and testosterone and folliculogenic disruption. Therefore, the aim of this study was to determine the effects of E2 (oestradiol-17β) replacement, Acyline (GnRH antagonist) and Flutamide (anti-androgen) treatment on ArKO female mice. WT and ArKO female mice (C57B6/J129; 16 weeks old; n = 6–8/grp) were assigned into three main groups: group 1 - received either E2 (0.05 mg) pellet or placebo, group 2 - received either a single s.c. injection of acyline (1.5 mg/kg/week) or placebo and group 3 – received either flutamide (25 mg) pellet or placebo for 3 weeks. Mice were subjected to daily vaginal smears. The ovaries and uterine horns were collected and weighed. One ovary and the uterine horns were fixed in formalin for histological assessment, while the other ovary was snap frozen in Ultraspec solution for RNA isolation and gene expression studies. Serum was collected for hormone measurements. All female ArKO mice exhibited an abnormal cycle that alternated between diestrus and early oestrus. E2 replacement restored the oestrus cycle in ArKO female mice but acyline and flutamide treatment did not. Histologically, hemorrhagic cystic follicles were present in all placebo, acyline and flutamide treated ArKO ovaries, however, E2 replacement improved the ovarian and uterine phenotypes. E2 replacement and acyline treatment also led to a decrease in serum gonadotropin levels in ArKO mice. In summary, E2 replacement could reverse the abnormal reproductive phenotype of the ArKO female mice. This study suggests that the reproductive phenotype of the ArKO female mouse is due to the direct effect of oestrogen and not due to the elevated circulating levels of gonadotrophins and testosterone. Supported by NH&MRC (Regkeys 241000, 338510 and 198705)

2005 ◽  
Vol 17 (9) ◽  
pp. 105
Author(s):  
J. Liew ◽  
A. E. Drummond ◽  
M. E. Jones ◽  
M. Poutanen ◽  
J. K. Findlay

Aromatase, the product of the Cyp 19 gene, converts androgens to estrogens. The role of estrogens within the ovary has recently been revisited; using the aromatase knockout (ArKO) mouse, we investigated the effect of estrogen deficiency on ovarian function. We now have an aromatase overexpressing (AROM+) female mouse model with elevated levels of estrogens. These mice were fertile and bred with FVB/N wildtype (WT) males, the AROM+ male being infertile. In this study we characterised the reproductive phenotype of the female AROM+ mouse. 5 WT and 10 AROM+ mice, 22–27 weeks of age were used in the study. The mice were subject to vaginal smears and killed during estrus. The ovaries, uterine horns and gonadal fat were collected and weighed. One ovary and the uterine horns were fixed in formalin for histological assessment, while the other ovary was snap frozen in Ultraspec solution for RNA isolation and gene expression studies. Serum was collected for hormone measurements. All AROM+ mice exhibited an abnormal pattern of cycling that in general, alternated between estrus and post-estrus. AROM+ mice were significantly heavier than their WT counterparts (WT 35.28 ± 2.89 g v. AROM+ 43.38 ± 2.11 g, P < 0.05). Ovarian, uterine and gonadal fat pad weights were not significantly different between the 2 groups (ovary: WT 17.4 ± 1.14 mg v. AROM+ 17.9 ± 0.06 mg; uterine horns: WT 89.7 ± 11.40 mg v. AROM+ 92.1 ± 6.64 mg; gonadal fat pads: WT 2.47 ± 0.62 g v. AROM+ 3.46±0.26 g). Histological, gene expression and hormone analyses are in progress. Our preliminary analyses indicated no significant effect of excess estrogen on ovarian, uterine and gonadal fat pad weights, despite the AROM+ mice being heavier. It remains to be determined as to whether the ovaries and uterine horns are histologically normal. Supported by the NHMRC (Regkeys 241000, 338510, 198705)


Author(s):  
P. Bagavandoss ◽  
JoAnne S. Richards ◽  
A. Rees Midgley

During follicular development in the mammalian ovary, several functional changes occur in the granulosa cells in response to steroid hormones and gonadotropins (1,2). In particular, marked changes in the content of membrane-associated receptors for the gonadotropins have been observed (1).We report here scanning electron microscope observations of morphological changes that occur on the granulosa cell surface in response to the administration of estradiol, human follicle stimulating hormone (hFSH), and human chorionic gonadotropin (hCG).Immature female rats that were hypophysectcmized on day 24 of age were treated in the following manner. Group 1: control groups were injected once a day with 0.1 ml phosphate buffered saline (PBS) for 3 days; group 2: estradiol (1.5 mg/0.2 ml propylene glycol) once a day for 3 days; group 3: estradiol for 3 days followed by 2 days of hFSH (1 μg/0.1 ml) twice daily, group 4: same as in group 3; group 5: same as in group 3 with a final injection of hCG (5 IU/0.1 ml) on the fifth day.


2014 ◽  
Vol 998-999 ◽  
pp. 228-232
Author(s):  
Zheng Hong Zhang ◽  
Fan Wang ◽  
Yan Qing Wu ◽  
Zong Hao Tang ◽  
Qing Qiang Lin ◽  
...  

Echinomycin (Ech) is a small-molecule inhibitor of hypoxia-inducible factor-1 DNA-binding activity, which plays a crucial role in the regulation of ovarian functions in mammals. The present study was designed to test the hypothesis that hypoxia-inducible factor (HIF)-1alpha-mediated proliferation cell nuclear antigen (PCNA) expressions contributed to the follicular development in the rat ovary primed by pregnant mare serum gonadotropin (PMSG). Through the histological examination, the decrease of growing and antral follicle numbers was found after Ech treatment both in control and PMSG treated groups. And then PCNA mRNA and protein expressions were found to significantly increase in the ovaries treated with PMSG, and the similar changes were found in HIF-1alpha mRNA and protein expressions, indicating PMSG-induced follicular development may be through HIF-1alpha/PCNA signaling. Furthermore, PCNA expression was found to significantly decrease in the ovaries after Ech treatment, while HIF-1alpha mRNA and protein expression was no obviously changes. Further analysis found the changes of PCNA expression were consistent with HIF-1 activity in the ovaries, further suggesting the regulatory roles in the follicular development. Taken together, these results demonstrated this HIF-1alpha-mediated PCNA expression is one of the important mechanisms regulating the ovarian follicular development in mammals. Keywords: HIF-1alpha; PCNA; echinomycin; HIF prolyl hyodroxylase acitvity; follicular development


2005 ◽  
Vol 347 (1) ◽  
pp. 156-158 ◽  
Author(s):  
Olha Khymenets ◽  
Jordi Ortuño ◽  
Montserrat Fitó ◽  
Ma Isabel Covas ◽  
Magí Farré ◽  
...  

2011 ◽  
pp. P1-300-P1-300
Author(s):  
Cary Lisa Dicken ◽  
Jun Shu ◽  
Davelene Israel ◽  
Genevieve Neal-Perry

2001 ◽  
Vol 114 (10) ◽  
pp. 1797-1798
Author(s):  
K. Plant

Essential Molecular Biology, Vol. 1, 2nd edn edited by T. A. Brown Oxford University Press (2000) 240 pages. ISBN 0–19-963642-7 pound29.95 I have heard it said (though not to my face) that practical molecular biology is somewhat akin to cookery, and I have to admit (though not to my fellow Molecular Biologists) that there is an element of truth in this. Of course, our ovens are cooler, and our pie dishes smaller, but often it is a case of mixing ingredients in the right proportions and baking at 37 degrees C for an hour. In this book Brown becomes the Delia Smith of molecular biology, starting with how to boil an egg, before proceeding to more complex recipes. It is utterly and unashamedly aimed at the complete novice. As more and more branches of biology use molecular techniques, and as a constant flow of graduates take up the yoke of research, there will always be a demand for this type of manual. Of course, it is possible to find variants of a lot of these methods on the Internet, but, as these often include only the protocol, the complete novice is probably better off with a specifically designed manual. Another option is to go for the kit approach, but, in the same way as opening a tin of beans doesn't make you a chef, I whole heartedly agree with Brown when he says, ‘do not get the idea that using kits is the same as being a molecular biologist.’ In most branches of biology a bit of genuine molecular expertise can only enhance one's future job prospects! One of the things I liked about this book is its no-nonsense style, particularly those chapters written by the Editor. There is plenty of sound advice, not just on the molecular techniques but on how to be a good scientist in general. Although the advice starts with the basics, it isn't patronising to those experienced in other fields. One piece of advice that particularly tickled me was that, if your hand is too unsteady to load a gel, you should give up caffeine; I'm not sure whether the pain would be worth the gain! The first chapter deals with all the basic issues, from planning (not just how to do it, but is it worthy of your time, which is something we should all think about occasionally) to safety (which nasties you'll be using, what precautions to take, with internet sites referenced to fill in the details) and what equipment you'll need to run the experiments. In a nutshell, the rest of the book deals with microbiology for molecular biologists and molecular biology for everyone else. This includes DNA and RNA isolation, electrophoresis and cloning (generating, propagating and identifying recombinant DNA molecules, not the Dolly-the-sheep variety). There is a second volume to the set, which (based on the contents of the first edition) should cover making and screening libraries, the polymerase chain reaction, sequencing and gene expression studies. Bear in mind that to get very far you will need to buy the second volume, which is not yet published. It has been more than a decade since the first edition of this well-known and respected manual was published; so one would think its first update is about due. However, compared with the first edition, most chapters have very few changes. This is probably in the nature of such a basic manual - for example, good microbial practice doesn't change much. Only a couple of chapters have been extensively rewritten; those describing DNA extraction now include more recent resin-based methods. So to the crux of the matter: would I recommend buying it? Well, if you're a complete novice with little backup, I definitely think it is worth investing in a decent manual, and this one does have a nice comfortable feel to it. If you've already got a copy of the previous edition and are wondering whether to upgrade, I would say that the few improvements in these very basic techniques do not really make it worth spending the pound30 that this volume costs. That said, I rather suspect that the second volume, which deals with more complex techniques, will show far more technical advances and should complete your progression from culinary incompetence to cordon bleu.


2020 ◽  
Vol 9 (4) ◽  
pp. 338-345
Author(s):  
Xin Liu ◽  
Chenmin Jiang ◽  
Yong Chen ◽  
Fangxiong Shi ◽  
Chaoqiang Lai ◽  
...  

2016 ◽  
Vol 28 (2) ◽  
pp. 201
Author(s):  
E. Andreas ◽  
D. Salilew-Wondim ◽  
M. Hoelker ◽  
C. Neuhoff ◽  
E. Tholen ◽  
...  

Normal follicular development, especially from the preantral stage until ovulation, is the critical to ensure the release of a developmentally competent oocyte. We have previously shown that among several clusters of microRNAs, microRNA-17-92 cluster (miR-17-5p, miR-19a, miR-20a, and miR-92a) is differentially expressed between bovine granulosa cells (bGC) derived from preovulatory dominant and subordinate follicles. Here, we aimed to investigate the regulatory role of microRNA-17-92 cluster in bGC function. Among the target genes predicted by the miRWalk database, BMPR2 and PTEN genes were experimentally validated using the pmirGLO Dual Luciferase Reporter Assay System (Promega Corporation, Madison, WI, USA). The bGC were aspirated from ovaries obtained from a local slaughterhouse. After determining cell viability and concentration using the trypan blue exclusion method, a total 2.5 × 105 bGC per well were seeded into CytoOne 24-well plate in DMEM/F12-Ham medium (Sigma Aldrich Chemie GmbH, Munich, Germany) supplemented with 10% FBS (Gibco BRL USA, Grand Isalnd, NY, USA) and 1% penicillin/streptomycin (Gibco BRL USA). Then, the bGC were cultured at 37°C with 5% CO2 and O2. To investigate the role of microRNA-17-92 cluster in bGC function, 100 nM of individual and cluster of microRNA-17-92 mimic, inhibitor, and negative controls were transfected into subconfluent-cultured bGC. The bGC were harvested 48 h post-transfection and used for RNA isolation and subsequent cDNA synthesis and expression analysis of candidate genes using real-time qPCR. Data analysis was performed using the comparative cycle threshold (Ct) method. A cell proliferation assay was performed using CCK-8 kit (Dojindo EU GmbH, Munich, Germany). Based on the cell diameter measurement done using ImageJ 1.48v software (National Institutes for Health, Bethesda, MD, USA), those bGC with diameter >14 µm were categorized as differentiated cells, whereas those with diameter = 14 µm were considered as undifferentiated cells. MicroRNA-17-92 cluster overexpression on bGC reduced both mRNA and protein expression of BMPR2 and PTEN genes, whereas inhibition of microRNA-17-92 cluster increased their expression. Bovine GC transfected with microRNA-17-92 cluster mimic showed higher proliferation activity and decreased rate of differentiation. The opposite phenotype was observed in bGC transfected with microRNA-17-92 cluster inhibitor. Similarly, miRNA-17-92 cluster mimic transfection increased the expression of markers of proliferation, CCND2 and PCNA, and resulted in down-regulation of CYP11A1 and STAR genes as markers of differentiation. The opposite expression pattern was observed after transfection of miRNA-17-92 cluster inhibitors. In conclusion, the miRNA-17-92 cluster members coordinately regulate bGC proliferation and differentiation by targeting the expression of BMPR2 and PTEN genes.


2009 ◽  
Vol 21 (1) ◽  
pp. 187 ◽  
Author(s):  
C. M. Barros ◽  
R. L. Ereno ◽  
M. F. Machado ◽  
J. Buratini ◽  
M. F. Pegorer ◽  
...  

During bovine follicular development, there is a phase known as follicular deviation in which the future dominant follicle grows faster than the other follicles and acquires LH receptors (LHR). In Nellore breed, deviation occurs 2.5 days after ovulation, and at this time, the dominant follicle has in average a diameter of 6.0 mm. Some authors believe that LHRs are present in the future dominant follicle before deviation and are essential for this process. However, others are convinced that LHRs are present only during or after follicular deviation. The aim of the present experiment was to evaluate the expression of 4 LHR isoforms (M1 to M4) in granulosa cells of follicles from Nellore heifers before, during, and after follicular deviation. At a random stage of the estrous cycle (D0), Nellore heifers (n = 21) received a progesterone intravaginal device (1.0 g, Primer®, Tecnopec, Sao Paulo, Brazil) and 2.5 mg of estradiol benzoate (EB, i.m., Estrogin®, Farmavet, Sao Paulo, Brazil). Eight days later (D8) PGF2α was administered (150 μg d-cloprostenol, i.m., Prolise®, ARSA S.R.L., Buenos Aires, Argentina), and the device was removed. Twenty-four hours after device removal, cows were treated with EB (1.0 mg, i.m.), and from this point in time, the growth of the dominant follicle growth was observed by ultrasonography (US, Aloka 900, Tokyo, Japan) every 12 h. The animals were allocated in 3 groups: Group 2 (G2, 2 days after ovulation, n = 7), Group 2.5 (G2.5, 2.5 days after ovulation, n = 7), and Group 3 (G3, 3 days after ovulation, n = 7), and were slaughtered 2, 2.5, and 3 days after ovulation, respectively, in order to remove the ovaries. The granulosa cells, obtained from ovarian follicles, were separated for total RNA extraction, and the gene expression of LHR isoforms was measured by semiquantitative RT-PCR. Since LHR expression was not detected in Group 2 (follicles with 4.5 to 6.7 mm), comparisons were performed between groups G2.5 and G3 by ANOVA. The LHR expression was detected only in 2 samples of Group G2 (7.0-mm follicles) and was significantly higher in Group G3 (63.6%; follicles from 8 to 14 mm, P < 0.05). In all samples that expressed LHR, the 4 isoforms were present. It is concluded that LHR expression is present in granulosa cells of follicles from Nellore heifers after follicular deviation. Support and fellowship from FAPESP (Sao Paulo, Brazil).We are grateful to Tecnopec (Sao Paulo, Brazil) for providing intravaginal devices used in the experiment.


2020 ◽  
Vol 26 (8) ◽  
pp. 615-623
Author(s):  
Zaher Merhi ◽  
Xiu Quan Du ◽  
Maureen J Charron

Abstract Maternal nutrition and the intrauterine environment are important in determining susceptibility to reproductive and metabolic disturbances. Advanced glycation end products (AGEs) are widely consumed in Western diet. The purpose of this study was to determine whether perinatal exposure to a high levels of dietary AGEs affect metabolic and reproductive parameters in female mice offspring. Female CD1 mice, 7 weeks old, were placed on either a diet low (L-AGE) or high (H-AGE) in AGEs before mating and then during pregnancy and lactation. All offspring were weaned onto the L-AGE diet and studied through to 16 weeks of age; they were counted and weighed at birth and then every week for a total of 11 weeks. Vaginal opening, litter size, growth curve, liver and abdominal fat weights, serum levels of anti-Mullerian hormone, leptin and adiponectin, as well as insulin and glucose tolerance tests were compared. Ovaries were harvested for follicular count and gene expression by real-time polymerase chain reaction. Compared to perinatal exposure to the L-AGE diet, perinatal exposure to the H-AGE diet caused lower body weight at birth, and adult offspring exhibited delayed growth, lower serum leptin and adiponectin levels, delayed vaginal opening, irregular oestrous cyclicity, arrested follicular development and significant alterations in the expression of genes involved in folliculogenesis (Amh and Amhr2) and steroidogenesis (Cyp19a1). These results indicate that perinatal exposure to a diet elevated in AGEs causes deficits in perinatal growth, pubertal onset, and reproductive organ development in female mice. Whether these findings translate to humans remains to be determined in future studies.


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