scholarly journals 203.Studies of the activin pathway in dominant and subordinate bovine follicles before, during and after selection

2004 ◽  
Vol 16 (9) ◽  
pp. 203
Author(s):  
B. C. Sisco ◽  
A. N. Shelling ◽  
P. L. Pfeffer
Keyword(s):  
Feedback Loop ◽  
Mrna Levels ◽  
Dominant Follicle ◽  
Rt Pcr ◽  
Protein Levels ◽  
Follicular Wave ◽  
Follicular Size ◽  
Quantitative Changes ◽  
Follicle Selection ◽  
Inhibin Subunits

In monovulatory species such as cattle, one of a cohort of developing follicles assumes dominancy and continues to grow in each follicular wave. After dominant follicle selection, pituitary-derived FSH levels decrease through a negative feedback loop mediated by oestradiol and inhibin A produced by the dominant follicle. The dominant follicle itself only requires very low basal levels of FSH, thus escaping atresia which is the fate of the subordinate follicles. The mechanisms involved in dominant follicle (DF) selection remain unclear. Most studies have focused on the stages following selection. To investigate what roles activin and inhibin play in DF selection we looked at the quantitative changes in the expression of the genes coding for the activin/inhibin subunits (Inhibin α, βA and βB) as well as other genes in the activin pathway (SMAD2, ActRIIA/B, follistatin (FST), FSHR). We examined mRNA levels in follicular granulosa cells (GCs) before (d1.5), during (d2.5) and after (d3.5 and 7) DF selection using real-time RT-PCR. Prior to DF selection, highest levels of inhibin βA, FST and SMAD2 transcripts converged on the largest follicles. Inhibin α, ActRIIA/B and FSHR levels did not correlate with follicular size at this stage. At Day 2.5, highest levels of inhibin βA, inhibin α, FST and SMAD2 transcripts were seen in a single putative DF. ActRIIA/B and FSHR did not show any difference between follicles. By Days 3.5 and 7, a dramatic difference in expression levels of inhibin βA, inhibin α and FST were seen in DF compared to SF. Yet in absolute terms inhibin βA levels decreased after selection, whereas inhibin α levels increased. Inhibin βB expression was only detected in Day 7 GCs and was significantly higher in the DF. These results suggest a shift from an activin environment during the pre and peri-DF selection period, to an inhibin environment following DF selection. Inhibin/activin protein levels in the follicular fluid using western ligand blotting confirmed this. We postulate that the higher activin activity within DF influences the selection mechanism as activin and inhibin have been shown to play a role in gonadotropin regulation in the ovary around the time of selection.

Negative Correlation Between Serum Levels of Homocysteine and Apolipoprotein M

2019 ◽  
Vol 19 (2) ◽  
pp. 120-126
Author(s):  
J. Wei ◽  
Y. Yu ◽  
Y. Feng ◽  
J. Zhang ◽  
Q. Jiang ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Hepg2 Cells ◽  
Serum Levels ◽  
Significant Negative Correlation ◽  
Mrna Levels ◽  
Rt Pcr ◽  
Apolipoprotein M ◽  
Protein Mass ◽  
Protein Levels ◽  
Phosphoinositide 3 Kinase

Background: Homocysteine (Hcy) has been suggested as an independent risk factor for atherosclerosis. Apolipoprotein M (apoM) is a constituent of the HDL particles. The goal of this study was to examine the serum levels of homocysteine and apoM and to determine whether homocysteine influences apoM synthesis. Methods: Serum levels of apoM and Hcy in 17 hyperhomocysteinemia (HHcy) patients and 19 controls were measured and their correlations were analyzed. Different concentrations of homocysteine (Hcy) and LY294002, a specific phosphoinositide 3- kinase (PI3K) inhibitor, were used to treat HepG2 cells. The mRNA levels were determined by RT-PCR and the apoM protein mass was measured by western blot. Results: We found that decreased serum apoM levels corresponded with serum HDL levels in HHcy patients, while the serum apoM levels showed a statistically significant negative correlation with the serum Hcy levels. Moreover, apoM mRNA and protein levels were significantly decreased after the administration of Hcy in HepG2 cells, and this effect could be abolished by addition of LY294002. Conclusions: resent study demonstrates that Hcy downregulates the expression of apoM by mechanisms involving the PI3K signal pathway.

scholarly journals Expression of Tachykinins and Tachykinin Receptors and Interaction with Kisspeptin in Human Granulosa and Cumulus Cells1

2016 ◽  
Vol 94 (6) ◽  
Author(s):  
Jordán García-Ortega ◽  
Francisco M. Pinto ◽  
Nicolás Prados ◽  
Aixa R. Bello ◽  
Teresa A. Almeida ◽  
...  
Keyword(s):  
Cell Function ◽  
Oocyte Retrieval ◽  
Cumulus Cells ◽  
Mrna Levels ◽  
Human Ovary ◽  
Rt Pcr ◽  
Protein Levels ◽  
Preovulatory Follicles ◽  
Nk3 Receptor ◽  
Nk2 Receptor

Abstract The neurokinin B/NK3 receptor (NK3R) and kisspeptin/kisspeptin receptor (KISS1R), two systems which are essential for reproduction, are coexpressed in human mural granulosa (MGC) and cumulus cells (CCs). However, little is known about the presence of other members of the tachykinin family in the human ovary. In the present study, we analyzed the expression of substance P (SP), hemokinin-1 (HK-1), NK1 receptor (NK1R), and NK2 receptor (NK2R) in MGCs and CCs collected from preovulatory follicles of oocyte donors at the time of oocyte retrieval. RT-PCR, quantitative RT-PCR, immunocytochemistry, and Western blotting were used to investigate the patterns of expression of tachykinin and tachykinin receptor mRNAs and proteins and the possible interaction between the tachykinin family and kisspeptin. Intracellular free Ca2+ levels ([Ca2+]i) in MGCs after exposure to SP or kisspeptin in the presence of SP were also measured. We found that SP, HK-1, the truncated NK1R isoform NK1R-Tr, and NK2R were all expressed in MGCs and CCs. NK1R-Tr mRNA and NK2R mRNA and protein levels were higher in MGCs than in CCs from the same patients. Treatment of cells with kisspeptin modulated the expression of HK-1, NK3R, and KISS1R mRNAs, whereas treatment with SP regulated kisspeptin mRNA levels and reduced the [Ca2+]i response produced by kisspeptin. These data demonstrate that the whole tachykinin system is expressed and acts in coordination with kisspeptin to regulate granulosa cell function in the human ovary.

scholarly journals Amniotic IGF-I supplementation of growth-restricted fetal sheep alters IGF-I and IGF receptor type 1 mRNA and protein levels in placental and fetal tissues

2005 ◽  
Vol 186 (1) ◽  
pp. 145-155 ◽  
Author(s):  
S Shaikh ◽  
F H Bloomfield ◽  
M K Bauer ◽  
H H Phua ◽  
R S Gilmour ◽  
...  
Keyword(s):  
Late Gestation ◽  
Mrna Levels ◽  
Rt Pcr ◽  
Igf Binding Proteins ◽  
Fetal Sheep ◽  
Hepatic Expression ◽  
Protein Levels ◽  
Igf I ◽  
Igf Receptor

We have previously reported that chronic intra-amniotic supplementation of the late gestation growth-restricted (IUGR) ovine fetus with IGF-I (20 μg/day) increased gut growth but reduced liver weight and circulating IGF-I concentrations. Here we report mRNA and protein levels of IGF-I, the type 1 IGF receptor (IGF-1R) and IGF-binding proteins (IGFBP)-1, -2 and -3 in fetal gut, liver, muscle and placenta from fetuses in that earlier study in an attempt to explain these contrasting results. mRNA and protein were extracted from tissues obtained at post mortem at 131 days of gestation (term, 145 days) from three groups of fetuses (control, IUGR+saline and IUGR+IGF-I, n=9 per group). Control fetuses were unembolised and untreated. In the IUGR groups, growth restriction was induced from 113 to 120 days by placental embolisation; from 120 to 130 days fetuses were treated with daily intra-amniotic injections of either saline or 20 μg IGF-I. mRNA was measured by RT-PCR or real-time RT-PCR, and protein by Western blot. In liver, muscle and placenta, IGF-I mRNA and protein levels were reduced by between 8 and 30% in IGF-I-treated fetuses compared with saline-treated fetuses and controls with no change in IGF-1R mRNA or protein levels. In contrast, in the gut, IGF-I mRNA and protein levels were not significantly altered with IGF-I treatment, but IGF-1R levels were increased, especially in the jejunum. Immunolocalisation demonstrated that IGF-1R expression was confined to the luminal aspect of the gut. mRNA levels of all three IGFBPs were reduced in the gut of IGF-I-treated fetuses, but hepatic expression was significantly increased. These data demonstrated tissue-specific regulation of IGF-I, IGF-1R and IGFBPs-1, -2 and -3 in response to intra-amniotic IGF-I supplementation, though the underlying mechanisms remain obscure.

scholarly journals Is there an inflammatory stimulus to human term labour?

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256545
Author(s):  
Natasha Singh ◽  
Bronwen Herbert ◽  
Garvin Sooranna ◽  
Nishel M. Shah ◽  
Ananya Das ◽  
...  
Keyword(s):  
Statistical Significance ◽  
P Value ◽  
Mrna Levels ◽  
Inflammatory Stimulus ◽  
Rt Pcr ◽  
Protein Levels ◽  
Decidua Basalis ◽  
Early Labour ◽  
Transcription Factor Activation ◽  
Term Labour

Inflammation is thought to play a pivotal role in the onset of term and some forms of preterm labour. Although, we recently found that myometrial inflammation is a consequence rather than a cause of term labour, there are several other reproductive tissues, including amnion, choriodecidua parietalis and decidua basalis, where the inflammatory stimulus to labour may occur. To investigate this, we have obtained amnion, choriodecidual parietalis and decidua basalis samples from women at various stages of pregnancy and spontaneous labour. The inflammatory cytokine profile in each tissue was determine by Bio-Plex Pro® cytokine multiplex assays and quantitative RT-PCR. Active motif assay was used to study transcription activation in the choriodecidua parietalis. Quantitative RT-PCR was use to study the pro-labour genes (PGHS-2, PGDH, OTR and CX43) in all of the tissues at the onset of labour and oxytocin (OT) mRNA expression in the choriodecidual parietalis and decidua basalis. Statistical significance was ascribed to a P value <0.05. In the amnion and choriodecidua parietalis, the mRNA levels of various cytokines decreased from preterm no labour to term no labour samples, but the protein levels were unchanged. The choriodecidua parietalis showed increase in the protein levels of IL-1β and IL-6 in the term early labour samples. In the amnion and decidua basalis, the protein levels of several cytokines rose in term established labour. The multiples of the median derived from the 19-plex cytokine assay were greater in term early labour and term established labour samples from the choriodecidua parietalis, but only in term established labour for myometrium. These data suggest that the inflammatory stimulus to labour may begin in the choriodecidua parietalis, but the absence of any change in prolabour factor mRNA levels suggests that the cytokines may act on the myometrium where we observed changes in transcription factor activation and increases in prolabour gene expression in earlier studies.

scholarly journals Stimulation of iodide uptake by human chorionic gonadotropin in FRTL-5 cells: effects on sodium/iodide symporter gene and protein expression

2002 ◽  
pp. 655-661 ◽  
Author(s):  
F Arturi ◽  
I Presta ◽  
D Scarpelli ◽  
JM Bidart ◽  
M Schlumberger ◽  
...  
Keyword(s):  
Western Blot ◽  
Chorionic Gonadotropin ◽  
Human Chorionic Gonadotropin ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Rt Pcr ◽  
Iodide Uptake ◽  
Protein Levels

BACKGROUND: Various clinical and experimental findings support the concept that human chorionic gonadotropin (hCG) can stimulate iodide uptake in thyroid cells. DESIGN: We investigated the molecular mechanisms underlying the effects of hCG on iodide uptake, and particularly its action on the expression of Na+/I- symporter (NIS) mRNA and protein. METHODS: Iodide uptake was analyzed in FTRL-5 cells by measuring (125)I concentrations in cells after a 30-min exposure to 0.1 microCi carrier-free Na (125)I in the presence or absence of hCG or, for control purposes, TSH. Expression of NIS mRNA and NIS protein synthesis were evaluated, respectively, with a semiquantitative 'multiplex' RT-PCR method and Western blot analysis. RESULTS: Iodide uptake was increased by hCG in a dose- and time-dependent manner: maximal effects were observed after 72 h of stimulation. The effect was cAMP dependent and paralleled that of TSH, although it lacked the early cycloheximide-independent component seen with TSH, and its peak effect was lower. Semiquantitative multiplex RT-PCR revealed that hCG produced a significant increase in NIS mRNA levels that was detectable after 4 h and peaked after 48 h. In contrast, in TSH-stimulated FRTL-5 cells, maximum NIS mRNA expression was observed after 24 h of stimulation. Western blot analysis demonstrated that hCG also caused a 2.5-fold increase over basal values in NIS protein levels, which was similar to that observed after TSH stimulation although the peak effects of the latter hormone were less marked and occurred earlier. CONCLUSION: Our data demonstrated that hCG stimulates iodide uptake in FRTL-5 cells by increasing NIS mRNA and protein levels. Thus, the functional status of the thyroid may be influenced by hCG-dependent changes in NIS expression occurring during pregnancy.

Identification of novel genes associated with dominant follicle development in cattle

2007 ◽  
Vol 19 (8) ◽  
pp. 967 ◽  
Author(s):  
Anna E. Zielak ◽  
Niamh Forde ◽  
Stephan D. E. Park ◽  
Fiona Doohan ◽  
Paul M. Coussens ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Follicular Development ◽  
Intracellular Signalling ◽  
Follicle Development ◽  
The Novel ◽  
Dominant Follicle ◽  
Novel Genes ◽  
Follicular Wave ◽  
New Genes ◽  
Follicle Selection

Follicle development is regulated by the interaction of endocrine and intrafollicular factors, as well as by numerous intracellular pathways, which involves the transcription of new genes, although not all are known. The aim of the present study was to determine the expression of a set of unknown genes identified by bovine cDNA microarray analysis in theca and granulosa cells of dominant and subordinate follicles, collected at a single stage of the first follicular wave using quantitative real-time polymerase chain reaction. Differences were further examined at three stages of the follicular wave (emergence, selection and dominance) and bioinformatics tools were used to identify these originally unknown sequences. The suggested name function and proposed role for the novel genes identified are as follows: MRPL41 and VDAC2, involved in apoptosis (dominant follicle development); TBC1D1 stimulates cell differentiation (growth associated with dominant follicle selection and development); STX7, promotes phagocytosis of cells (subordinate follicle regression); and SPC22 and EHD3, intracellular signalling (subordinate follicle regression). In conclusion, we have identified six novel genes that have not been described previously in ovarian follicles that are dynamically regulated during dominant follicle development and presumably help mediate intracellular signalling, cell differentiation, apoptosis and phagocytosis, events critical to follicular development.

scholarly journals Follicle selection in cattle and horses: role of intrafollicular factors

Reproduction ◽  
2006 ◽  
Vol 132 (3) ◽  
pp. 365-377 ◽  
Author(s):  
M A Beg ◽  
O J Ginther
Keyword(s):  
The Other ◽  
Dominant Follicle ◽  
Follicular Wave ◽  
Igf System ◽  
Igf I ◽  
The Future ◽  
Igf Binding ◽  
Preparatory Stage ◽  
Igf Binding Protein ◽  
Follicle Selection

The eminent event in follicle selection during a follicular wave in monovular species is diameter deviation, wherein one follicle continues to grow (developing dominant) and other follicles (subordinates) begin to regress. In cattle, the IGF system, oestradiol and LH receptors are involved in the intrafollicular events initiating deviation as indicated by the following: (1) concentrations of free IGF-I and oestradiol in the follicular fluid and number of LH receptors in the follicular wall increase more dramatically in the future dominant follicle than in the future subordinate follicles before the beginning of deviation and (2) ablation of the largest follicle (LF) or injection of recombinant human IGF (rhIGF)-I into the second LF at the expected beginning of deviation increases the concentrations of oestradiol in second LF before the expected beginning of deviation between second LF and third LF. In horses, an increase in free IGF-I, oestradiol, inhibin-A and activin-A is greater in the future dominant follicle than in other follicles before the beginning of deviation. However, free IGF-I is the only one of these four factors needed for the initiation of deviation in horses as indicated by the following: (1) ablation of LF at the expected beginning of deviation increases the concentrations of free IGF-I in second LF before the beginning of deviation between second LF and third LF but does not increase the other factors; (2) injection of rhIGF-I into second LF at the expected beginning of deviation causes second LF to continue to grow and become a codominant follicle and (3) injection of IGF-binding protein-3 into LF at the expected beginning of deviation causes LF to regress and second LF to become dominant. Thus, the dramatic changes in the IGF system in LF compared to other follicles before the beginning of deviation play a crucial role in the events that lead to the beginning of diameter deviation in both cattle and horses. Oestradiol and LH receptors also play a role in cattle. These intrafollicular events prepare the selected follicle for the decreasing availability of FSH and increasing availability of LH. The other follicles of the wave have the same future capability but do not have adequate time to attain a similar preparatory stage.

scholarly journals Necessity for LH in selection and continued growth of the bovine dominant follicle

Reproduction ◽  
2020 ◽  
Vol 159 (5) ◽  
pp. 559-569 ◽  
Author(s):  
Victor E Gomez-León ◽  
O J Ginther ◽  
Rafael R Domingues ◽  
José D Guimarães ◽  
Milo C Wiltbank
Keyword(s):  
Chorionic Gonadotropin ◽  
Acute Treatment ◽  
Gnrh Antagonist ◽  
Underlying Mechanism ◽  
Dominant Follicle ◽  
Follicle Growth ◽  
Follicular Wave ◽  
Treatment Data ◽  
Follicle Selection ◽  
Selection Of

Previous research demonstrated that acute treatment with GnRH antagonist, Acyline, allowed follicle growth until ~8.5 mm and no dominant follicle was selected. This study evaluated whether deficient LH was the underlying mechanism for Acyline effects by replacing LH action, using human chorionic gonadotropin (hCG), during Acyline treatment. Holstein heifers (n = 24) during first follicular wave were evaluated by ultrasound and randomized into one of three treatments: Control (saline treatments), Acyline (5 µg/kg Acyline), or Acyline+hCG (Acyline plus 50 IU of hCG at start then 100 IU every 12 h). Pulses of LH were present in Control heifers (9 Pulses/10 h) but not during Acyline treatment. Data were normalized to the transition to diameter deviation (day 0; F1 ~7.5 mm). Diameter deviation of the largest (F1) and the second largest (F2) follicle was not observed in Acyline-treated heifers, whereas control heifers had decreased growth of F2 at F1 ~7.5 mm, indicating deviation. Selection of a single dominant follicle was restored by providing LH activity in Acyline+hCG heifers, as evidenced by F1 and F2 deviation, continued growth of F1, and elevated circulating estradiol. Separation of F1 and F2 occurred 12 h (~7.0 mm) earlier in Acyline+hCG heifers than Controls. Circulating FSH was greater in Acyline than Controls, but lower in Acyline+hCG than Controls after day 1.5. In conclusion, dominant follicle selection and growth after follicle deviation is due to LH action as shown by inhibition of this process during ablation of GnRH-stimulated LH pulses with Acyline and restoration of it after replacement of LH action by hCG treatment.

255 GENE EXPRESSION OF Cox 5a, 5b, AND 6b1 AND THEIR ROLES IN PRE-IMPLANTATION OF MOUSE EMBRYOS

2006 ◽  
Vol 18 (2) ◽  
pp. 235
Author(s):  
S.-E. Lee ◽  
X.-Y. Li ◽  
X.-S. Cui ◽  
N.-H. Kim
Keyword(s):  
Rna Interference ◽  
Mrna Expression ◽  
Real Time ◽  
Oocyte Maturation ◽  
Blastocyst Stage ◽  
Mrna Levels ◽  
Rt Pcr ◽  
Target Mrna ◽  
Protein Levels

Despite clear evidence of regulation of mitochondrial respiration by nuclear encoded genes, cytochrome oxidase (Cox), little information is available on their expression and functional roles during early embryonic development. To examine the role of Cox in oocyte maturation and embryogenesis, we first characterized mRNA and protein levels of nuclear encoded genes, Cox 5a, 5b, and 6b1, in mouse oocytes and during early embryogenesis, using real-time RT-PCR and immunocytochemistry. We then examined the possible role of these genes in oocyte maturation and pre-implantation development using RNA interference analysis. The relative abundances of Cox 5a, 5b, and 6b1 transcripts was measured by real time RT-PCR. After normalization by comparison to histone H2a mRNA levels, the mRNA expression of Cox 5a, 5b, and 6b1 were found to be considerable in mature oocytes and zygotes, but reduced slightly in 2-cell embryos. From the 2-cell to the blastocyst stage, mRNA expression is dependent on the number of blastomeres, as expression increases only gradually with development. Immunocytochemical studies revealed that Cox 5a, 5b, and 6b1 proteins were expressed in all blastomeres of the blastocyst. Injection of Cox 5a, 5b, or 6b1 siRNA into GV stage oocytes decreased expression of the target mRNA specifically, while not affecting the expression of mRNAs for the other subunits in mature oocytes. Similarly, each siRNA injection into zygotes specifically reduced target mRNA expression at the 2-cell, morula and blastocyst stages (P < 0.05). Silencing of mRNA expression by RNA interference (siRNA) did not inhibit oocyte maturation or developmental events up to the morula and blastocyst stages. The expression level of mtDNA9, as well as overall levels of mitochondrial mRNAs, was not different following injection of siRNA for Cox 5a, 5b, or 6b1. However, it is evident that the number of mitochondria in siRNA treated blastocysts was greatly reduced, and they appeared to be morphologically abnormal. Significantly higher apoptosis and lower cell numbers were observed in siRNA treated blastocysts. Real time RT PCR revealed that silencing of Cox 5a, 5b, and 6b1 decreased mRNA and protein levels of E-cadherin. These results suggest that the Cox subunits, Cox 5a, 5b, and 6b1, play an important role in mitochondrial function during pre-implantation development. This work was funded by a grant from the National Research Laboratory Program in Korea.

scholarly journals Effect of Ligustrazine on Endometrium Injury of Thin Endometrium Rats

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Qing Ye ◽  
Yu Zhang ◽  
Jiulu Fu ◽  
Yi Zou ◽  
Wei Zhao ◽  
...  
Keyword(s):  
Western Blotting ◽  
Uterine Cavity ◽  
Control Group ◽  
Mrna Levels ◽  
Histopathological Changes ◽  
Model Group ◽  
Rt Pcr ◽  
Thin Endometrium ◽  
Protein Levels ◽  
Hematoxylin Eosin

The purpose of this experiment is to establish a rat model of thin endometrium and to explore the effect of ligustrazine on the thin endometrium of rats. The thin endometrium model was made by using infusing absolute ethyl alcohol into the uterine cavity. The thickness of endometrium was measured. Hematoxylin-Eosin (HE) staining was used to observe the histopathological changes of endometrium. The mRNA levels of VEGF, VEGFR-2, PI3K, and AKT were detected by RT-PCR. Western blotting was used to detect the levels of VEGF, VEGFR-2, PI3K, and AKT in endometrial tissue. The thickness of endometrium in the model group was significantly thinner than that in the control group. Compared with the model group, the thickness of endometrium in ligustrazine group was increased. HE staining shown that ligustrazine restored the histopathological changes of endometrium. RT-PCR and Western Blotting results showed that the mRNA and protein levels of VEGF, VEGFR-2, PI3K, and AKT in the model group were significantly decreased compared with the control group, while ligustrazine restored the changes. Ligustrazine can improve the morphology of endometrium, can promote the growth of endometrium, and has obvious therapeutic effect. Its mechanism is related to the activation of PI3K/Akt signaling pathway through upregulation of VEGF and VEGFR-2 expression to induce the repair of thin endometrium in rats.

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