scholarly journals Activin and Glucocorticoids Synergistically Activate Follicle-Stimulating Hormone β-Subunit Gene Expression in the Immortalized LβT2 Gonadotrope Cell Line

Endocrinology ◽  
2007 ◽  
Vol 148 (2) ◽  
pp. 762-773 ◽  
Author(s):  
Shauna M. McGillivray ◽  
Varykina G. Thackray ◽  
Djurdjica Coss ◽  
Pamela L. Mellon
Keyword(s):  
Gene Expression ◽  
Cell Line ◽  
Synergistic Interaction ◽  
Β Subunit ◽  
Subunit Gene ◽  
Rate Limiting Step ◽  
Reproductive Axis ◽  
Glucocorticoid Signaling ◽  
Tumor Virus

FSH is produced by the pituitary gonadotrope to regulate gametogenesis. Production of the β-subunit of FSH is the rate-limiting step in FSH synthesis, and a number of peptide and steroid hormones within the reproductive axis have been found to regulate transcription of the FSH β-subunit gene. Although both activin and glucocorticoids are notable regulators of FSHβ by themselves, we find that cotreatment results in a synergistic interaction on the mouse FSHβ promoter at the level of the gonadotrope using transient transfection of a reporter gene into the LβT2 immortalized gonadotrope-derived cell line. This synergistic interaction is specific to FSHβ, because only additive effects of these two hormones are observed on LH β-subunit, GnRH receptor, and mouse mammary tumor virus gene expression. Components of both activin and glucocorticoid signaling are found to be necessary for synergy, and there are specific cis elements on the mouse FSHβ promoter that contribute to the synergistic response as well. We also identify novel activin-responsive regions in the mouse FSHβ promoter and find that the −120 site can bind Smad2/3 in vitro. In addition, the glucocorticoid receptor and Smad3 are sufficient to confer a striking synergy with glucocorticoids on the mouse FSHβ promoter. Our studies provide the first evidence of a synergistic interaction between activin and glucocorticoids within the gonadotrope cell and demonstrate that this synergy can occur directly at the level of the mouse FSHβ promoter.

scholarly journals Differential Effects of Gonadotropin-Releasing Hormone (GnRH) Pulse Frequency on Gonadotropin Subunit and GnRH Receptor Messenger Ribonucleic Acid Levels in Vitro*

Endocrinology ◽  
1997 ◽  
Vol 138 (3) ◽  
pp. 1224-1231 ◽  
Author(s):  
Ursula B. Kaiser ◽  
Andrzej Jakubowiak ◽  
Anna Steinberger ◽  
William W. Chin
Keyword(s):  
Gene Expression ◽  
Messenger Rna ◽  
Pulse Frequency ◽  
Gnrh Receptor ◽  
Pituitary Cells ◽  
Mrna Levels ◽  
Subunit Gene ◽  
Differential Effects ◽  
Messenger Ribonucleic Acid

Abstract The hypothalamic hormone, GnRH, is released and transported to the anterior pituitary in a pulsatile manner, where it binds to specific high-affinity receptors and regulates gonadotropin biosynthesis and secretion. The frequency of GnRH pulses changes under various physiological conditions, and varying GnRH pulse frequencies have been shown to regulate differentially the secretion of LH and FSH and the expression of the gonadotropin α, LHβ, and FSHβ subunit genes in vivo. We demonstrate differential effects of varying GnRH pulse frequency in vitro in superfused primary monolayer cultures of rat pituitary cells. Cells were treated with 10 nm GnRH pulses for 24 h at a frequency of every 0.5, 1, 2, or 4 h. α, LHβ, and FSHβ messenger RNA (mRNA) levels were increased by GnRH at all pulse frequencies. α and LHβ mRNA levels and LH secretion were stimulated to the greatest extent at a GnRH pulse frequency of every 30 min, whereas FSHβ mRNA levels and FSH secretion were stimulated maximally at a lower GnRH pulse frequency, every 2 h. GnRH receptor (GnRHR) mRNA levels also were increased by GnRH at all pulse frequencies and were stimulated maximally at a GnRH pulse frequency of every 30 min. Similar results were obtained when the dose of each pulse of GnRH was adjusted to maintain a constant total cumulative dose of GnRH over 24 h. These data show that gonadotropin subunit gene expression is regulated differentially by varying GnRH pulse frequencies in vitro, suggesting that the differential effects of varying GnRH pulse frequencies on gonadotropin subunit gene expression occur directly at the level of the pituitary. The pattern of regulation of GnRHR mRNA levels correlated with that of α and LHβ but was different from that of FSHβ. This suggests that α and LHβ mRNA levels are maximally stimulated when GnRHR levels are relatively high, whereas FSHβ mRNA levels are maximally stimulated at lower levels of GnRHR expression, and that the mechanism for differential regulation of the gonadotropins by varying pulse frequencies of GnRH may involve levels of GnRHR. Furthermore, these data suggest that the mechanisms whereby varying GnRH pulse frequencies stimulate α, LHβ, and GnRHR gene expression are similar, whereas the stimulation of FSHβ mRNA levels may be different.

scholarly journals Does Bromelain-Cisplatin Combination Afford In-Vitro Synergistic Anticancer Effects on Human Prostatic Carcinoma Cell Line, PC3?

2020 ◽  
Vol 9 ◽  
pp. 1749
Author(s):  
Fatemeh Amini Chermahini ◽  
Elham Raeisi ◽  
Mathias Hossain Aazami ◽  
Abbas Mirzaei ◽  
Esfandiar Heidarian ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Viability ◽  
Cell Line ◽  
Colony Formation ◽  
Prostatic Carcinoma ◽  
Carcinoma Cell ◽  
Quantitative Polymerase Chain Reaction ◽  
Chemotherapeutic Agents ◽  
Carcinoma Cell Line

Background: Bromelain enhances anticancer impacts to chemotherapeutic agents. The question as to whether bromelain does promote in-vitro cytotoxic and proapoptotic effects of cisplatin on human prostatic carcinoma PC3 cell line was investigated. Materials and Methods: PC3 (human prostatic carcinoma) cells were treated either single or in combination with bromelain and/or cisplatin. MTT, clonogenic assay, flow cytometry and real-time quantitative polymerase chain reaction were used to investigate cell viability, colony formation, proapoptotic potential and p53 gene expression, respectively. Results: Cisplatin (IC10) combined with bromelain (IC40) significantly affected PC3 cell viability, inhibited colony formation, as well increased p53 proapoptotic gene expression compared to cisplatin single treatment. Nevertheless, bromelain-cisplatin chemoherbal combination did not display any additive proapoptotic effect compared to single treatments. Conclusion: Bromelain-cisplatin chemoherbal combination demonstrated synergistic in-vitro anticancer effect on human prostatic carcinoma cell line, PC3, that drastically reduced required cisplatin dose. [GMJ.2020;9:e1749]

24 GLOBAL TRANSCRIPT PROFILING OF CLONED BOVINE BLASTOCYSTS USING AFFYMETRIX GENECHIP TECHNOLOGY

2006 ◽  
Vol 18 (2) ◽  
pp. 120
Author(s):  
Z. Beyhan ◽  
P. Ross ◽  
A. Iager ◽  
A. Kocabas ◽  
K. Cunniff ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Line ◽  
Expression Profiles ◽  
Cell Structure ◽  
Donor Cell ◽  
Lipid Binding ◽  
Differentially Expressed ◽  
Gtp Binding ◽  
Cloned Bovine

Identification of genes implicated in the biological processes of somatic cell nuclear transfer will improve our understanding of reprogramming events, i.e. the transformation of a lineage-committed cell into a pluripotent one. In addition, the gene expression profile of cloned embryos can help explain the widely reported developmental failures in cloned animals. In this study, we investigated global gene expression profiles of bovine in vitro-fertilized and cloned embryos using Gene Chip Bovine Genome Arrays (Affymetrix, Inc., Santa Clara, CA, USA). For the generation of cloned bovine blastocysts from two adult fibroblast lines (C and D), we employed methods previously proven to generate live offspring and compared these offspring to in vitro-produced blastocysts. Total RNA isolated from groups of 10 blastocysts was amplified by a template-switching PCR. Amplified cDNAs were used to synthesize biotin-labeled antisense RNAs (aRNAs) during and in vitro transcription reaction. Labeled aRNAs were hybridized to microarrays as described by the manufacturer. Experiments were performed in four replicates. Expression data were analyzed using the Significance Analysis of Microarrays (SAM; Tusher et al. 2001 Proc. Natl. Acad. Sci. 98, 5116-5121) procedure and software. Overall, 48.4% and 46% of 23 000 bovine transcripts spotted on the arrays were present in cloned and in in vitro-produced control blastocysts, respectively. The SAM procedure identified 43 genes that changed at least 1.5-fold, with an estimated false discovery rate (FDR) of 20%. Comparison of gene expression between NT embryos produced from two different cell lines and IVF controls with the same criteria revealed 6 (clones from cell line C vs. IVF) and 46 (clones from cell line D vs. IVF) differentially expressed genes. The number of transcripts expressed differentially between the cloned embryos with different donor cell origin was 437. Of the 43 differentially expressed transcripts in cloned blastocysts, 13 have unknown functions and the rest of the genes related to cell structure (tuftelin, desmoplakin), cell cycle/mitosis (Kinesin like 4, katanin, stathmin, PCNA), energy metabolism (lactate dehydrogenase, ATPsynthase, lipid-binding protein, keto acid dehydrogenase E1, metallothionein), and cell signaling (GTP-binding protein1, GTP binding stimulatory protein). Our results indicate that expression profiles of cloned blastocysts could be affected by somatic donor cell.

scholarly journals Androgen Suppresses In Vivo and In Vitro LH Pulse Secretion and Neural Kiss1 and Tac2 Gene Expression in Female Mice

Endocrinology ◽  
2020 ◽  
Vol 161 (12) ◽  
Author(s):  
Lourdes A Esparza ◽  
Tomohiro Terasaka ◽  
Mark A Lawson ◽  
Alexander S Kauffman
Keyword(s):  
Gene Expression ◽  
Pulse Frequency ◽  
Normal Male ◽  
Steroid Abuse ◽  
Female Mice ◽  
Reproductive Axis ◽  
Lh Pulsatility ◽  
Lh Secretion

Abstract Androgens can affect the reproductive axis of both sexes. In healthy women, as in men, elevated exogenous androgens decrease gonad function and lower gonadotropin levels; such circumstances occur with anabolic steroid abuse or in transgender men (genetic XX individuals) taking androgen supplements. The neuroendocrine mechanisms by which endogenous or exogenous androgens regulate gonadotropin release, including aspects of pulsatile luteinizing hormone (LH) secretion, remain unknown. Because animal models are valuable for interrogating neural and pituitary mechanisms, we studied effects of androgens in the normal male physiological range on in vivo LH secretion parameters in female mice and in vitro LH secretion patterns from isolated female pituitaries. We also assessed androgen effects on hypothalamic and gonadotrope gene expression in female mice, which may contribute to altered LH secretion profiles. We used a nonaromatizable androgen, dihydrotestosterone (DHT), to isolate effects occurring specifically via androgen receptor (AR) signaling. Compared with control females, DHT-treated females exhibited markedly reduced in vivo LH pulsatility, with decreases in pulse frequency, amplitude, peak, and basal LH levels. Correlating with reduced LH pulsatility, DHT-treated females also exhibited suppressed arcuate nucleus Kiss1 and Tac2 expression. Separate from these neural effects, we determined in vitro that the female pituitary is directly inhibited by AR signaling, resulting in lower basal LH levels and reduced LH secretory responses to gonadotropin-releasing hormone pulses, along with lower gonadotropin gene expression. Thus, in normal adult females, male levels of androgen acting via AR can strongly inhibit the reproductive axis at both the neural and pituitary levels.

In vitro model of angiogenesis using a human endothelium-derived permanent cell line: Contributions of induced gene expression, G-proteins, and integrins

1992 ◽  
Vol 153 (3) ◽  
pp. 437-449 ◽  
Author(s):  
Jeffrey Bauer ◽  
Michael Margolis ◽  
Clara Schreiner ◽  
Cora-Jean Edgell ◽  
Jane Azizkhan ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Line ◽  
G Proteins ◽  
In Vitro Model ◽  
Permanent Cell Line ◽  
Permanent Cell ◽  
Vitro Model ◽  
Human Endothelium

scholarly journals A Retinoid-Resistant Acute Promyelocytic Leukemia Subclone Expresses a Dominant Negative PML-RARα Mutation

Blood ◽  
1997 ◽  
Vol 89 (12) ◽  
pp. 4282-4289 ◽  
Author(s):  
Wenlin Shao ◽  
Laura Benedetti ◽  
William W. Lamph ◽  
Clara Nervi ◽  
Wilson H. Miller
Keyword(s):  
Gene Expression ◽  
Retinoic Acid ◽  
Ligand Binding ◽  
Cell Line ◽  
Acute Promyelocytic Leukemia ◽  
Regulation Of Gene Expression ◽  
Promyelocytic Leukemia ◽  
Dominant Negative

Abstract The unique t(15; 17) of acute promyelocytic leukemia (APL) fuses the PML gene with the retinoic acid receptor α (RARα) gene. Although retinoic acid (RA) inhibits cell growth and induces differentiation in human APL cells, resistance to RA develops both in vitro and in patients. We have developed RA-resistant subclones of the human APL cell line, NB4, whose nuclear extracts display altered RA binding. In the RA-resistant subclone, R4, we find an absence of ligand binding of PML-RARα associated with a point mutation changing a leucine to proline in the ligand-binding domain of the fusion PML-RARα protein. In contrast to mutations in RARα found in retinoid-resistant HL60 cells, in this NB4 subclone, the coexpressed RARα remains wild-type. In vitro expression of a cloned PML-RARα with the observed mutation in R4 confirms that this amino acid change causes the loss of ligand binding, but the mutant PML-RARα protein retains the ability to heterodimerize with RXRα and thus to bind to retinoid response elements (RAREs). This leads to a dominant negative block of transcription from RAREs that is dose-dependent and not relieved by RA. An unrearranged RARα engineered with this mutation also lost ligand binding and inhibited transcription in a dominant negative manner. We then found that the mutant PML-RARα selectively alters regulation of gene expression in the R4 cell line. R4 cells have lost retinoid-regulation of RXRα and RARβ and the RA-induced loss of PML-RARα protein seen in NB4 cells, but retain retinoid-induction of CD18 and CD38. Thus, the R4 cell line provides data supporting the presence of an RARα-mediated pathway that is independent from gene expression induced or repressed by PML-RARα. The high level of retinoid resistance in vitro and in vivo of cells from some relapsed APL patients suggests similar molecular changes may occur clinically.

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