scholarly journals HDAC inhibitors impair Fshb subunit expression in murine gonadotrope cells

2019 ◽  
Vol 62 (2) ◽  
pp. 67-78 ◽  
Author(s):  
Gauthier Schang ◽  
Chirine Toufaily ◽  
Daniel J Bernard

Fertility is dependent on follicle-stimulating hormone (FSH), a product of gonadotrope cells of the anterior pituitary gland. Hypothalamic gonadotropin-releasing hormone (GnRH) and intra-pituitary activins are regarded as the primary drivers of FSH synthesis and secretion. Both stimulate expression of the FSH beta subunit gene (Fshb), although the underlying mechanisms of GnRH action are poorly described relative to those of the activins. There is currently no consensus on how GnRH regulates Fshb transcription, as results vary across species and between in vivo and in vitro approaches. One of the more fully developed models suggests that the murine Fshb promoter is tonically repressed by histone deacetylases (HDACs) and that GnRH relieves this repression, at least in immortalized murine gonadotrope-like cells (LβT2 and αT3-1). In contrast, we observed that the class I/II HDAC inhibitor trichostatin A (TSA) robustly inhibited basal, activin A-, and GnRH-induced Fshb mRNA expression in LβT2 cells and in primary murine pituitary cultures. Similar results were obtained with the class I specific HDAC inhibitor, entinostat, whereas two class II-specific inhibitors, MC1568 and TMP269, had no effects on Fshb expression. Collectively, these data suggest that class I HDACs are positive, not negative, regulators of Fshb expression in vitro and that, contrary to earlier reports, GnRH may not stimulate Fshb by inhibiting HDAC-mediated repression of the gene.

2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Sabina Wang ◽  
Lillianne G Harris ◽  
Santhosh Mani ◽  
Donald Menick

Cardiac hypertrophy is often associated with the activation of signaling pathways that perpetuate altered calcium efflux and influx. One gene that is upregulated and contributes to altered intracellular calcium concentrations and worsening contractility during cardiac hypertrophy is the Sodium Calcium Exchanger ( Ncx1 ). Molecular studies implicate histone deacetylases (HDACs) in possibly regulating the expression of this gene. Our recent work reveals that HDAC1, HDAC5 and Sin3a interact and are recruited to the Ncx1 promoter through the Nkx2.5 transcription factor. Interestingly, we observed greater associated/interaction of the HDAC1-HDAC5/Sin3a repressor complex upon broad HDAC inhibition. Taken together, we hypothesized that HDAC inhibition, stabilizes an HDAC1-HDAC5/Sin3a repressor complex during cardiac hypertrophy. We addressed this hypothesis by treating isolated adult cardiomyocytes with class specific HDAC inhibitors since HDAC1 is a Class I HDAC and HDAC5 is a Class IIa HDAC. Co-Immunoprecipitation (Co-IP) revealed a greater association of repressor complex molecules in the presence of Entinostat, a Class I HDAC inhibitor compared to both non-treated control and TSA, a broad HDAC inhibitor (n=3). These works show enhanced recruitment Sin3a (co-repressor) at the proximal promoter of NCX1 as demonstrated by Chromatin-Immunoprecipitation (ChIP) (n=3). To test whether these observations translated into in vivo models, we subjected mice to transaortic constriction (TAC) to induce hypertrophy. In this model, Co-IP revealed results that similar to our in vitro studies with greater immuno- detection of repressor complex component, Sin3a after immune-precipitation with HDAC1. Furthermore, our ChIP data showed a greater PCR product amplification of proximal Ncx1 promoter, from experimental groups that were subjected to Entinostat (n=3). Our cumulative data suggests that Class I HDAC inhibition stabilizes a repressor complex on the Ncx1 promoter that hinders hypertrophy- mediated Ncx1 upregulation. Class specific HDAC inhibition may be useful in the stabilization and repression of aberrantly expressed genes that contribute to poor clinical outcomes in cardiac hypertrophy.


Author(s):  
Satoshi Kamimura ◽  
Kimiko Inoue ◽  
Eiji Mizutani ◽  
Jin-Moon Kim ◽  
Hiroki Inoue ◽  
...  

Abstract In mammalian cloning by somatic cell nuclear transfer (SCNT), treatment of reconstructed embryos with histone deacetylase (HDAC) inhibitors improves efficiency. So far, most of those used for SCNT are hydroxamic acid derivatives—such as trichostatin A—characterized by their broad inhibitory spectrum. Here, we examined whether mouse SCNT efficiency could be improved using chlamydocin analogues, a family of newly designed agents that specifically inhibit Class I and IIa HDACs. Development of SCNT-derived embryos in vitro and in vivo revealed that four out of five chlamydocin analogues tested could promote the development of cloned embryos. The highest pup rates (7.1 to 7.2%) were obtained with Ky-9, similar to those achieved with trichostatin A (7.2 to 7.3%). Thus, inhibition of Class I and/or IIa HDACs in SCNT-derived embryos is enough for significant improvements in full-term development. In mouse SCNT, the exposure of reconstructed oocytes to HDAC inhibitors is limited to 8–10 h because longer inhibition with Class I inhibitors causes a 2-cell developmental block. Therefore, we used Ky-29, with higher selectivity for Class IIa than Class I HDACs for longer treatment of SCNT-derived embryos. As expected, 24-h treatment with Ky-29 up to the 2-cell stage did not induce a developmental block, but the pup rate was not improved. This suggests that the 1-cell stage is a critical period for improving SCNT cloning using HDAC inhibitors. Thus, chlamydocin analogues appear promising for understanding and improving the epigenetic status of mammalian SCNT-derived embryos through their specific inhibitory effects on HDACs.


Blood ◽  
2010 ◽  
Vol 116 (3) ◽  
pp. 406-417 ◽  
Author(s):  
Jiro Kikuchi ◽  
Taeko Wada ◽  
Rumi Shimizu ◽  
Tohru Izumi ◽  
Miyuki Akutsu ◽  
...  

Abstract Bortezomib is now widely used for the treatment of multiple myeloma (MM); however, its action mechanisms are not fully understood. Despite the initial results, recent investigations have indicated that bortezomib does not inactivate nuclear factor-κB activity in MM cells, suggesting the presence of other critical pathways leading to cytotoxicity. In this study, we show that histone deacetylases (HDACs) are critical targets of bortezomib, which specifically down-regulated the expression of class I HDACs (HDAC1, HDAC2, and HDAC3) in MM cell lines and primary MM cells at the transcriptional level, accompanied by reciprocal histone hyperacetylation. Transcriptional repression of HDACs was mediated by caspase-8–dependent degradation of Sp1 protein, the most potent transactivator of class I HDAC genes. Short-interfering RNA-mediated knockdown of HDAC1 enhanced bortezomib-induced apoptosis and histone hyperacetylation, whereas HDAC1 overexpression inhibited them. HDAC1 overexpression conferred resistance to bortezomib in MM cells, and administration of the HDAC inhibitor romidepsin restored sensitivity to bortezomib in HDAC1-overexpressing cells both in vitro and in vivo. These results suggest that bortezomib targets HDACs via distinct mechanisms from conventional HDAC inhibitors. Our findings provide a novel molecular basis and rationale for the use of bortezomib in MM treatment.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4164-4164
Author(s):  
Fumihiko Hayakawa ◽  
Issay Kitabayashi ◽  
Pier P. Pandolfi ◽  
Tomoki Naoe

Abstract The promyelocytic leukemia (PML) protein is a potent tumor suppressor and proapoptotic factor, and is functionally regulated by posttranslational modification such as phosphorylation, sumoylation, and ubiquitination. Histone deacetylase (HDAC) inhibitors are a promising class of targeted anticancer agents and induce apoptosis to cancer cells. In addition to their effects on histones, HDAC inhibitors increase the acetylation level of several non-histone proteins such as transcription factors, which are important for their effects to cancer cells. However, the mechanism of HDAC inhibitor-induced apoptocis is largely unknown. We report here a novel posttranscriptional modification, acetylation, of PML. By the screening using antibody array, we identified PML as a new acetylation target of Trichostatin A (TSA), a HDAC inhibitor. PML acetylation was enhanced by coexpression of p300 or treatment with TSA. We also showed that increased PML acetylation was associated with increased sumoylation of PML in vitro and in vivo. PML involvement in TSA-induced apoptosis was demonstrated by PML knocking down in Hela cells or PML overexpression in PML−/− MEF cells. Furthermore, PML with acetylation-defective mutation showed disability to mediate the apoptosis, suggesting the importance of PML acetylation for it. Our work provides new insights into the PML regulation by posttranslational modification, and new information about the therapeutic mechanism of HDAC inhibitors.


2012 ◽  
Vol 303 (10) ◽  
pp. F1443-F1453 ◽  
Author(s):  
Chung-Hsi Hsing ◽  
Chiou-Feng Lin ◽  
Edmund So ◽  
Ding-Ping Sun ◽  
Tai-Chi Chen ◽  
...  

Bone morphogenetic protein (BMP)-7 protects sepsis-induced acute kidney injury (AKI). Dexmedetomidine (DEX), an α2-adrenoceptor (α2-AR) agonist, has anti-inflammatory effects. We investigated the protective effects of DEX on sepsis-induced AKI and the expression of BMP-7 and histone deacetylases (HDACs). In vitro , the effects of DEX or trichostatin A (TSA, an HDAC inhibitor) on TNF-α, monocyte chemotactic protein (MCP-1), BMP-7, and HDAC mRNA expression in LPS-stimulated rat renal tubular epithelial NRK52E cells, was determined using real-time PCR. In vivo, mice were intraperitoneally injected with DEX (25 μg/kg) or saline immediately and 12 h after cecal ligation and puncture (CLP) surgery. Twenty-four hours after CLP, we examined kidney injury and renal TNF-α, MCP-1, BMP-7, and HDAC expression. Survival was monitored for 120 h. LPS increased HDAC2, HDAC5, TNF-α, and MCP-1 expression, but decreased BMP-7 expression in NRK52E cells. DEX treatment decreased the HDAC2, HDAC5, TNF-α, and MCP-1 expression, but increased BMP-7 and acetyl histone H3 expression, whose effects were blocked by yohimbine, an α2-AR antagonist. With DEX treatment, the LPS-induced TNF-α expression and cell death were attenuated in scRNAi-NRK52E but not BMP-7 RNAi-NRK52E cells. In CLP mice, DEX treatment increased survival and attenuated AKI. The expression of HDAC2, HDAC5, TNF-α, and MCP-1 mRNA in the kidneys of CLP mice was increased, but BMP-7 was decreased. However, DEX treatment reduced those changes. DEX reduces sepsis-induced AKI by decreasing TNF-α and MCP-1 and increasing BMP-7, which is associated with decreasing HDAC2 and HDAC5, as well as increasing acetyl histone H3.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Xuejie Jiang ◽  
Ling Jiang ◽  
Jiaying Cheng ◽  
Fang Chen ◽  
Jinle Ni ◽  
...  

Abstract Background Epigenetic dysregulation plays important roles in leukemogenesis and the progression of acute myeloid leukemia (AML). Histone acetyltransferases (HATs) and histone deacetylases (HDACs) reciprocally regulate the acetylation and deacetylation of nuclear histones. Aberrant activation of HDACs results in uncontrolled proliferation and blockade of differentiation, and HDAC inhibition has been investigated as epigenetic therapeutic strategy against AML. Methods Cell growth was assessed with CCK-8 assay, and apoptosis was evaluated by flow cytometry in AML cell lines and CD45 + and CD34 + CD38- cells from patient samples after staining with Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI). EZH2 was silenced with short hairpin RNA (shRNA) or overexpressed by lentiviral transfection. Changes in signaling pathways were detected by western blotting. The effect of chidamide or EZH2-specific shRNA (shEZH2) in combination with adriamycin was studied in vivo in leukemia-bearing nude mouse models. Results In this study, we investigated the antileukemia effects of HDAC inhibitor chidamide and its combinatorial activity with cytotoxic agent adriamycin in AML cells. We demonstrated that chidamide suppressed the levels of EZH2, H3K27me3 and DNMT3A, exerted potential antileukemia activity and increased the sensitivity to adriamycin through disruption of Smo/Gli-1 pathway and downstream signaling target p-AKT in AML cells and stem/progenitor cells. In addition to decreasing the levels of H3K27me3 and DNMT3A, inhibition of EZH2 either pharmacologically by chidamide or genetically by shEZH2 suppressed the activity of Smo/Gli-1 pathway and increased the antileukemia activity of adriamycin against AML in vitro and in vivo. Conclusions Inhibition of EZH2 by chidamide has antileukemia activity and increases the chemosensitivity to adriamycin through Smo/Gli-1 pathway in AML cells (Fig. 5). These findings support the rational combination of HDAC inhibitors and chemotherapy for the treatment of AML.


2002 ◽  
Vol 22 (13) ◽  
pp. 4890-4901 ◽  
Author(s):  
Sophie Deltour ◽  
Sébastien Pinte ◽  
Cateline Guerardel ◽  
Bohdan Wasylyk ◽  
Dominique Leprince

ABSTRACT HIC1 (hypermethylated in cancer) and its close relative HRG22 (HIC1-related gene on chromosome 22) encode transcriptional repressors with five C2H2 zinc fingers and an N-terminal BTB/POZ autonomous transcriptional repression domain that is unable to recruit histone deacetylases (HDACs). Alignment of the HIC1 and HRG22 proteins from various species highlighted a perfectly conserved GLDLSKK/R motif highly related to the consensus CtBP interaction motif (PXDLSXK/R), except for the replacement of the virtually invariant proline by a glycine. HIC1 strongly interacts with mCtBP1 both in vivo and in vitro through this conserved GLDLSKK motif, thus extending the CtBP consensus binding site. The BTB/POZ domain does not interact with mCtBP1, but the dimerization of HIC1 through this domain is required for the interaction with mCtBP1. When tethered to DNA by fusion with the Gal4 DNA-binding domain, the HIC1 central region represses transcription through interactions with CtBP in a trichostatin A-sensitive manner. In conclusion, our results demonstrate that HIC1 mediates transcriptional repression by both HDAC-independent and HDAC-dependent mechanisms and show that CtBP is a HIC1 corepressor that is recruited via a variant binding site.


2012 ◽  
Vol 56 (7) ◽  
pp. 3849-3856 ◽  
Author(s):  
Subathdrage D. M. Sumanadasa ◽  
Christopher D. Goodman ◽  
Andrew J. Lucke ◽  
Tina Skinner-Adams ◽  
Ishani Sahama ◽  
...  

ABSTRACTHistone deacetylase (HDAC) enzymes posttranslationally modify lysines on histone and nonhistone proteins and play crucial roles in epigenetic regulation and other important cellular processes. HDAC inhibitors (e.g., suberoylanilide hydroxamic acid [SAHA; also known as vorinostat]) are used clinically to treat some cancers and are under investigation for use against many other diseases. Development of new HDAC inhibitors for noncancer indications has the potential to be accelerated by piggybacking onto cancer studies, as several HDAC inhibitors have undergone or are undergoing clinical trials. One such compound, SB939, is a new orally active hydroxamate-based HDAC inhibitor with an improved pharmacokinetic profile compared to that of SAHA. In this study, thein vitroandin vivoantiplasmodial activities of SB939 were investigated. SB939 was found to be a potent inhibitor of the growth ofPlasmodium falciparumasexual-stage parasitesin vitro(50% inhibitory concentration [IC50], 100 to 200 nM), causing hyperacetylation of parasite histone and nonhistone proteins. In combination with the aspartic protease inhibitor lopinavir, SB939 displayed additive activity. SB939 also potently inhibited thein vitrogrowth of exoerythrocytic-stagePlasmodiumparasites in liver cells (IC50, ∼150 nM), suggesting that inhibitor targeting to multiple malaria parasite life cycle stages may be possible. In an experimentalin vivomurine model of cerebral malaria, orally administered SB939 significantly inhibitedP. bergheiANKA parasite growth, preventing development of cerebral malaria-like symptoms. These results identify SB939 as a potent new antimalarial HDAC inhibitor and underscore the potential of investigating next-generation anticancer HDAC inhibitors as prospective new drug leads for treatment of malaria.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2022-2022
Author(s):  
Hua Cao ◽  
Rui Gao Fei ◽  
Albert A. Bowers ◽  
Thomas J. Greshock ◽  
Tenaya Newkirt ◽  
...  

Abstract Abstract 2022 Poster Board I-1044 Previous studies have demonstrated that Histone Deacetylase (HDAC) inhibitors such as butyrate and several short chain fatty acids, can induce fetal hemoglobin in humans and animal models; however induction of Hb F is achieved in relatively high concentrations of these compounds. We have previously investigated the induction of human γ globin gene activity by the prototypical HDAC inhibitor, FK228. The results demonstrated that FK228 is a more potent γ globin gene inducer compared to other HDAC inhibitors we have tested before (Am J Hematol. 12:981). In this study, we investigated the induction of human γ globin gene function of largazole and it's thiol analogue in vitro in cultures of normal human adult BFUe and in vivo in the mice carrying a human γ globin transgene. Largazole is a HDAC inhibitor which was recently isolated from a marine vyanobacterium by Luesch and co-workers. Structural features of largazole, a macrocyclic depsopeptide, closely resemble those of FK228, FR901375 and spiruchostatin. We have reported that largazole and numerous synthetic analogues are highly potent Class I histone deacetylase inhibitors (J Am Chem Soc. 130:11219, J Am Chem Soc. 2009 Feb 4). We used flow cytometry to measure the in vitro effect of largazole and it's derivatives on the frequency of HbF-positive erythroblasts in BFUe cultures from normal individuals; real-time quantitative PCR (RT-qPCR) and high performance liquid chromatography (HPLC) were used to measure the in vivo effects of largazole on human γ globin induction in γ transgenic mice carrying a human γ globin gene.. Our results show that largazole and it's thiol derivative are potent γ hemoglobin gene inducers. In the human BFUe cultures, largazole increased the levels of fetal hemoglobin positive cells from 21.9% (control level) to 62.8% at a concentration of 0.1μM; largazole thiol increased the levels of fetal hemoglobin positive cells to 62.0% at a concentration of 1μM. Transgenic mice carrying the human μLCR Aγ construct continue to express the human γ gene in the adult stage (Blood. 77:1326). Largazole was administered through IP injection at the dosages of 0.3mg/kg/day and 0.6mg/kg/day, 5 days per week, for 2 weeks to two cohorts of transgenic mice. Largazole at the dose of 0.3mg/kg/day increased the level of human γ mRNA at the end of injection by 160.7%; at a dose of 0.6mg/kg/day human γ mRNA increased by 174.7%. At the 0.6mg/kg/day dosage the level of fetal hemoglobin in the peripheral blood of the animals increased by 3.4 and 3.2 fold at day 21 and day 28, respectively. These results provide strong in vitro and in vivo evidence that Largazole and it's thiol analogue are potent HbF inducers acting at low concentrations, and thus provide promising alternatives to compounds currently considered for induction of Hb F in patients with sickle cell disease and thalassemia. Disclosures: No relevant conflicts of interest to declare.


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