OBJECTIVE: To study the role and mechanism of histone deacetylase 1 (HDAC1) and histone deacetylase 2 (HDAC2) in mouse neuronal development. METHODS: The mice with Synapsin1-Cre recombinase were bred with RESULTS: The mice with CONCLUSIONS Deletion of
Animals ; Blotting, Western ; Histone Deacetylase 1/genetics* ; Histone Deacetylase 2 ; Histone Deacetylases/genetics* ; Immunohistochemistry ; Mice ; Neurons/metabolism* ; Signal Transduction

Oogenesis is the basic reproductive process of female mammals and is essential for fertilization and embryo development. Recent studies have shown that epigenetic modifications play an important role in the regulation of mammalian reproductive processes (such as oogenesis, spermatogenesis, preimplantation embryo development and sex differentiation). Taking histone acetylation as an instance, the dynamic changes of histone acetyltransferases (HATs) and deacetylases (HDACs) are involved in the regulation of gene activation and inactivation when numerous key physiological events occur during reproduction. Thereinto, HDAC1 and HDAC2, which are highly homologous in terms of both structure and function, play a pivotal role in murine oogenesis. HDAC1 and 2 jointly regulate the global transcription and the incidence of apoptosis of growing oocytes and affect its subsequent growth and development, which reflects their compensatory function. In addition, HDAC1 and 2 also play a specific part in oogenesis respectively. It has shown that HDAC2 is more critical than HDAC1 for oocyte development, which regulates de novo DNA methylation and chromosome segregation. Reciprocally, HDAC1 is more critical than HDAC2 for preimplantation development. Deficiency of HDAC1 causes the decreased proliferation of embryonic stem cells and the smaller embryoid bodies with irregular shape. In this review, we summarized the role and the current research progress of HDAC1/2 in murine oogenesis, to provide a reference for further understanding the relationship between epigenetic modifications and reproductive regulation.
Acetylation ; Animals ; Embryonic Development ; Female ; Histone Deacetylase 1/metabolism* ; Histone Deacetylase 2/metabolism* ; Histone Deacetylases/metabolism* ; Male ; Mice ; Oocytes ; Oogenesis

OBJECTIVE: To investigate the regulation of miR-34a on HDAC1 expression and its effect on the apoptosis of acute myeloid leukemia (AML) cells. METHODS: miR-34a mimics, miR-34a inhibitor and miR-34a scramble were transfected into HL-60 cells. The effects of miR-34a expression levels on proliferation and apoptosis of HL-60 cell were detected by CCK8 assay and flow cytometry respectively. The expression of HDAC1 protein was assessed by Western blot after regulating miR-34a expression, the 3'UTR of HDAC1 was cloned and ligated to construct a dual luciferase reporter vector, and then the dual luciferase reporter assay was applied to verify the target of miR-34a, the expression vector pcDNA3.1-HDAC1 was constructed, the interaction of miR-34a and HDAC1 was analyzed by reversion test. RESULTS: miR-34a over-expression could inhibit the proliferation of HL-60 cells and induce their apoptosis. Bioinformatics analysis indicated that the HDAC1 was a target gene of miR-34a. Western blot indicated that miR-34a overexpression down-regulated the expression of HDAC1. Dual luciferase reporter assay and reversion test showed that miR-34a could act at the 3-UTR of HDAC1 gene to regulate its expression. CONCLUSION miR-34a promotes the apoptosis of HL-60 cells via regulating HDAC1 expression.
Apoptosis ; Cell Proliferation ; HL-60 Cells ; Histone Deacetylase 1 ; metabolism ; Humans ; Leukemia, Myeloid, Acute ; genetics ; MicroRNAs ; genetics

BACKGROUNDPlacental multidrug resistance-associated protein 2 (MRP2), encoded by ABCC2 gene in human, plays a significant role in regulating drugs' transplacental transfer rates. Studies on placental MRP2 regulation could provide more therapeutic targets for individualized and safe pharmacotherapy during pregnancy. Currently, the roles of epigenetic mechanisms in regulating placental drug transporters are still unclear. This study aimed to investigate the effect of histone deacetylases (HDACs) inhibition on MRP2 expression in the placental trophoblast cell line and to explore whether HDAC1/2/3 are preliminarily involved in this process.

METHODSThe human choriocarcinoma-derived trophoblast cell line (Bewo cells) was treated with the HDAC inhibitors-trichostatin A (TSA) at different concentration gradients of 0.5, 1.0, 3.0, and 5.0 μmol/L. Cells were harvested after 24 and 48 h treatment. Small interfering RNA (siRNA) specific for HDAC1/HDAC2/HDAC3 or control siRNA was transfected into cells. Total HDAC activity was detected by colorimetric assay kits. HDAC1/2/3/ABCC2 messenger RNA (mRNA) and protein expressions were determined by real-time quantitative polymerase chain reaction and Western-blot analysis, respectively. Immunofluorescence for MRP2 protein expression was visualized and assessed using an immunofluorescence microscopy and ImageJ software, respectively.

RESULTSTSA could inhibit total HDAC activity and HDAC1/2/3 expression in company with increase of MRP2 expression in Bewo cells. Reduction of HDAC1 protein level was noted after 24 h of TSA incubation at 1.0, 3.0, and 5.0 μmol/L (vs. vehicle group, all P < 0.001), accompanied with dose-dependent induction of MRP2 expression (P = 0.045 for 1.0 μmol/L, P = 0.001 for 3.0 μmol/L, and P < 0.001 for 5.0 μmol/L), whereas no significant differences in MRP2 expression were noted after HDAC2/3 silencing. Fluorescent micrograph images of MRP2 protein were expressed on the cell membrane. The fluorescent intensities of MRP2 in the control, HDAC2, and HDAC3 siRNA-transfected cells were week, and no significant differences were noticed among these three groups (all P > 0.05). However, MRP2 expression was remarkably elevated in HDAC1 siRNA-transfected cells, which displayed an almost 3.19-fold changes in comparison with the control siRNA-transfected cells (P < 0.001).

CONCLUSIONSHDACs inhibition could up-regulate placental MRP2 expression in vitro, and HDAC1 was probably to be involved in this process.

Cell Line ; Histone Deacetylase 1 ; metabolism ; Histone Deacetylase 2 ; metabolism ; Histone Deacetylase Inhibitors ; pharmacology ; Histone Deacetylases ; metabolism ; Humans ; Hydroxamic Acids ; pharmacology ; Microscopy, Fluorescence ; Multidrug Resistance-Associated Proteins ; genetics ; metabolism ; RNA, Messenger ; Trophoblasts ; cytology ; metabolism

OBJECTIVETo investigate the effect of histone acetylation/deacetylation imbalances on embryonic hearts of mice and its effect on key genes of planar cell polarity (PCP) pathway-Vangl2, Scrib and Rac1 in H9C2 cells.

METHODSForty pregnant C57/B6 mice were randomly assigned into three groups: blank group (n=10), vehicle group (n=10), and valproic acid (VPA)-treated group (n=20). In the VPA-treated group, VPA, a histone deacetylase (HDAC) inhibitor, was administered to each individual dam intraperitoneally at a single dose of 700 mg/kg on embryonic day 10.5 (E10.5). The vehicle and blank groups received equivalent saline or no interventions, respectively. Dams were sacrificed on E15.5, and death rates of embryos were evaluated. Subsequently, embryonic hearts of survival fetus were removed to observe cardiac abnormalities by hematoxylin-eosin (HE) staining. H9C2 cells were cultured and allotted to the blank, vehicle, and VPA-treated groups: the VPA treated group received VPA exposure at concentrations of 2.0, 4.0 and 8.0 mmol/L; the vehicle and blank groups received equivalent saline or no interventions, respectively. HDAC1-3 as well as Vangl2, Scrib and Rac1 mRNA and protein expression levels were determined by quantitative real-time PCR and Western blot, respectively. The total HDAC activity was analyzed by colorimetric assay.

RESULTSThe fetus mortality rate after VPA treatment was 31.7%, with a significantly higher rate of cardiac abnormalities in comparison with the controls (P<0.05). In comparison with the blank and vehicle groups, HDAC1 mRNA was significantly increased at various concentrations of VPA treatment at all time points of exposure (P<0.05), together with a reduction of protein level after 48 and 72 hours of exposure (P<0.05). The inhibition of HDAC2 mRNA after various concentrations of VPA incubation was pronounced at 24 hours of exposure (P<0.05), while the protein levels were reduced at all time points (P<0.05). HDAC3 mRNA was prominently induced by VPA (4.0 and 8.0 mmol/L) at all time points of treatment (P<0.05). In contrast, the protein level was inhibited after VPA treatment (P<0.05). In comparison with the blank and vehicle groups, Vangl2 mRNA as well as Scrib mRNA/protein expression levels were markedly reduced after 48 and 72 hours of VPA treatment (P<0.05), together with a reduction of protein level in Vangl2 at 72 hours (P<0.05). Compared with the blank and vehicle groups, a significant repression in the total HDAC activity was observed in the VPA-treated group at concentrations of 4.0 and 8.0 mmol/L after 24 hours of treatment (P<0.05), and the effect persisted up to 48 and 72 hours, exhibiting pronounced inhibition at all concentrations (P<0.05).

CONCLUSIONSVPA might result in acetylation/deacetylation imbalances by inhibiting HDAC1-3 protein expression and total HDAC activity, leading to the down-regulation of mRNA and protein expression of Vangl2 and Scrib. This could be one of the mechanisms contributing to congenital heart disease.

Acetylation ; Animals ; Cell Polarity ; Cells, Cultured ; Fetal Heart ; drug effects ; metabolism ; Heart Defects, Congenital ; etiology ; Histone Deacetylase 1 ; genetics ; Histone Deacetylase 2 ; genetics ; Histones ; metabolism ; Mice ; Mice, Inbred C57BL ; Nerve Tissue Proteins ; genetics ; RNA, Messenger ; analysis ; Valproic Acid ; pharmacology

To confirm whether class I histone deacetylase inhibitors (HDACIs) are effective in relief of peripheral inflammatory pain, the effects of two selective inhibitors, MS-275 and MGCD0103, were studied in rats inflamed by subcutaneous (s.c.) injection of bee venom (BV). The BV test is characterized by displaying both persistent spontaneous nociception (PSN) and primary hypersensitivity. Intrathecal (i.t.) pre-treatment of either MS-275 or MGCD0103 with a single dose of 60 nmol/20 μL resulted in profound suppression of both PSN and primary thermal hypersensitivity but without significant influence upon the primary mechanical hypersensitivity and mirror-image thermal hypersensitivity. Moreover, the up-regulation of both HDAC1 and HDAC2 induced by s.c. BV injection was completely suppressed by i.t. pre-treatment of MS-275. The present results provide with another new line of evidence showing involvement of epigenetic regulation of chromatin structure by HDAC1/2-mediated histone hypoacetylation in the BV-induced PSN and thermal hypersensitivity and demonstrate the beneficial effects of class I HDACIs in prevention of peripheral inflammatory pain from occurring.
Animals ; Bee Venoms ; administration & dosage ; Benzamides ; pharmacology ; Epigenesis, Genetic ; Histone Deacetylase 1 ; genetics ; metabolism ; Histone Deacetylase 2 ; genetics ; metabolism ; Histone Deacetylase Inhibitors ; pharmacology ; Hot Temperature ; Hyperalgesia ; drug therapy ; Inflammation ; drug therapy ; Injections, Subcutaneous ; Nociception ; Pain ; chemically induced ; drug therapy ; Pain Measurement ; Pyridines ; pharmacology ; Pyrimidines ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Up-Regulation

OBJECTIVETo investigate the inhibitory effect of trichostatin A (TSA) on the proliferation of HepG2 cells and explore the underlying mechanism.

METHODSHepG2 cells exposed to different concentrations of TSA for 24, 48, or 72 h were examined for cell growth inhibition using a cell counting kit, changes in cell cycle distribution with flow cytometry, cell apoptosis with annexin V-FTIC/PI double staining, and cell morphology changes under inverted microscope. The expressions of beta-catenin, HDAC1, HDAC3, H3K9, cyclinD1 and Bax proteins in the exposed cells were detected by Western blotting, and the expressions of HDAC1 and HDAC3 mRNAs by quantitative fluorescent PCR.

RESULTSExposure to TSA caused significant dose- and time-dependent inhibition of HepG2 cell proliferation (P<0.05) and resulted in increased cell percentage in G0/G1 and G2/M phases and decreased cell percentage in S phase. The apoptotic index in the control group was (6.22 ± 0.25)%, which increased to (7.17 ± 0.20)% and (18.14 ± 0.42)% after exposure to 250 and 500 nmol/L TSA, respectively. Exposure to 250 and 500 nmol/L TSA also caused cell morphology changes with numerous floating cells. The expressions of beta-catenin, H3K9 and Bax proteins were significantly increased and CyclinD1, HDAC1, and HDAC3 protein expressions decreased in TSA-treated cells, but the expressions of HDAC1 and HDAC3 mRNAs showed no significant changes.

CONCLUSIONSTSA can inhibit the proliferation of HepG2 cells and induce cell cycle arrest and apoptosis by inhibiting HDAC activity, promoting histone acetylation, and activating Wnt/beta-catenin signaling pathway.

Acetylation ; Apoptosis ; Cell Cycle Checkpoints ; Cell Proliferation ; drug effects ; Cyclin D1 ; metabolism ; Hep G2 Cells ; drug effects ; Histone Deacetylase 1 ; metabolism ; Histone Deacetylases ; metabolism ; Histones ; metabolism ; Humans ; Hydroxamic Acids ; pharmacology ; Wnt Signaling Pathway ; bcl-2-Associated X Protein ; metabolism ; beta Catenin ; metabolism

OBJECTIVETo investigate the effect of silencing histone deacetylases 1 (HDAC1) gene by RNA interference on the proliferation, apoptosis and histone modulation in gastric cancer MGC-803 cell line.

METHODSThe optimal segment targeting HDAC1 gene was designed and transfected into MGC-803 cells by Lipofectamine TM2000. HDAC1 mRNA and protein in the transfected cells were detected by RT-PCR and Western blotting, respectively. The growth inhibition of MGC803 cells was evaluated by MTT assay and the cell apoptosis was detected with TUNEL assay. The expression of Bcl-2, procaspase-9, procaspase-3, c-Myc, histone acetylation of H3, H4, and histone methylation of H3K9 was detected by Western blotting.

RESULTSThe siRNA targeting HDAC1HDAC1 markedly suppressed mRNA expression, inhibited cell proliferation and induced apoptosis of MGC-803 cells in a concentration manner. Transfection of the cells with HDAC1 siRNA at 0, 30, 60, and 120 nmol/L for 24 h resulted in a cell apoptotic rate of (4.8∓2.7)%, (18.5∓3.5)%, (41.4∓4.3)%, and (59.2∓5.5)%, respectively, and caused down-regulation of the expressions of Bcl-2, proCaspase9, proCaspase3 and c-Myc, upregulation of histone acetylation of H3, H4, and down-regulation of histone methylation of H3K9.

CONCLUSIONSilencing HDAC1 gene expression with HDAC1 siRNA can promote histone H3 and H4 acetylation and inhibit histone methylation of H3K9 to suppress the proliferation and induce apoptosis of gastric cancer MGC-803 cells.

Acetylation ; Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Gene Silencing ; Gene Targeting ; Histone Deacetylase 1 ; genetics ; Histones ; metabolism ; Humans ; Methylation ; RNA Interference ; RNA, Small Interfering

This study is to investigate the effect of downregulation histone deacetylases 1 (HDAC1) gene by the technology of RNA interference on the differentiation of HL-60 cells line. The optimal segment targeting HDAC1 gene was designed and transfected into HL-60 cells by Lipofectamine 2000. The HDAC1 mRNA and protein level were detected by RT-PCR and Western blotting. The morphologic change of HL-60 cells was detected by an optical microscope with Wright-Giemsa. Cell differentiation was tested by NBT reduction assay. Expression of CD13, CD33 and CD14 was measured by flow cytometry. The results indicated that HDAC1 mRNA and protein were markedly suppressed by the siRNA targeting HDAC1 in a concentration-dependent manner. HDAC1 siRNA promoted cell differentiation. HL-60 cells became more mature in morphology after transfected to HDAC1 siRNA at a concentration of 30-60 nmol x L(-1) for 24 h. NBT reduction ability of HDAC1 siRNA with 30 nmol x L(-1) was 0.31 +/- 0.09, compared with negative control (0.20 +/- 0.02) (t = -3.1, P < 0.01), and with 60 nmol x L(-1) was 0.25 +/- 0.02 in comparison with negative control (0.21 +/- 0.04) (t = -2.12, P < 0.05). But it has no change in HDAC1 siRNA > or = 120 nmol x L(-1). After transfection with 60 nmol x L(-1) HDAC1 siRNA to HL-60 cells, the expression of CD13 was (96.50 +/- 0.70)% in compared to siRNA-NC (3.39 +/- 0.68) % (t = 164.9, P < 0.000 5), CD33 was (66.73 +/- 0.50) % in compared to siRNA-NC (96.80 +/- 1.70) % (t = 43.4, P < 0.000 5). CD14 was (0.53 +/- 0.00) % by comparison with siRNA-NC (0.49 +/- 0.02) % (t = -0.97, P > 0.1). HDAC1 siRNA promoted cell differentiation in indicated concentration. HDAC1 might be one of the targets of gene therapy for leukemia.
CD13 Antigens ; metabolism ; Cell Differentiation ; Down-Regulation ; HL-60 Cells ; Histone Deacetylase 1 ; genetics ; metabolism ; Humans ; Lipopolysaccharide Receptors ; metabolism ; RNA Interference ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; Sialic Acid Binding Ig-like Lectin 3 ; metabolism ; Transfection

The aim of this study was to illustrate the mechanism of inhibiting the cell growth in diffuse large B-cell lymphoma by histone deacetylase inhibitor valproic acid (VPA) combined with mTOR inhibitor temsirolimus (TEM). MTT assay and Wright's stain were used to assess cell growth inhibition and to detect the cell morphological changes respectively. The cell apoptosis, cell cycle and cell autophagy were determined by flow cytometry. Ultrastructure changes were confirmed by electron microscopy. Protein changes were detected by Western blot. The results showed that both VPA and TEM alone inhibited cell proliferation and the effect was more obvious in the combination group. VPA combined with TEM induced cell arrest in G0/G1 phase and upregulated the expression of autophagy-related protein LC3, without cell apoptosis. Moreover, typical autophagosomes were observed, further confirming the presence of autophagy. Western blot showed the changes of proteins involved in autophagy signaling pathway. VPA decreased HDAC1 and HDAC3 expression and increased histone acetylation, suggesting that VPA also affected lymphoma cell proliferation through epigenetic modification. It is concluded that the combined treatment of VPA and TEM induces cell cycle arrest and cell autophagy, which provides a new clue for their clinical application in diffuse large B-cell lymphoma.
Autophagy ; drug effects ; Cell Cycle Checkpoints ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Epigenesis, Genetic ; Histone Deacetylase 1 ; metabolism ; Histone Deacetylases ; metabolism ; Humans ; Lymphoma, Large B-Cell, Diffuse ; pathology ; Microtubule-Associated Proteins ; metabolism ; Sirolimus ; administration & dosage ; analogs & derivatives ; pharmacology ; Valproic Acid ; administration & dosage ; pharmacology