Sevoflurane inhibits proliferation and invasion of breast cancer cells by promoting SIRT2 expression and inducing ACLY deacetylation / 中华内分泌外科杂志

Objective:To explore the effects of sevoflurane (Sev) on proliferation and invasion of breast cancer cells.Methods:Normal human breast epithelial cell line MCF10A and human breast cancer cell line MCF7 were purchased. The expression level of sirtuin 2 (SIRT2) , ATP citrate lyase (ACLY) in breast cancer cells and acetylation level of ACLY were measured. Breast cancer cells were divided into the following groups: Control group, 2% SEV group, 4% SEV group, si-NC group, si-SIRT2 group, 4% SEV+si-NC group, 4% SEV+si-SIRT2 group, SIRT2 group, SIRT2+ACLY-WT group, SIRT2+ACLY-3KQ group, SIRT2+ACLY-3KQ+4% SEV group, si-ACLY group, si-ACLY+ACLY-WT group, si-ACLY+ACLY-3KQ group. MTT and Transwell assay were used to detect cell proliferation and invasion.Results:Compared with MCF-10A cells (1.00±0.15) , SIRT2 was low expressed in Control group cells (0.43±0.03) ( q=11.98, P<0.001) , SEV could induce the expression of SIRT2 ( F=88.71, P<0.001) . In addition, ACLY and ACLY-3K acetylation level were up-regulated in breast cancer cells (all P<0.05) . Knockdown of SIRT2 or overexpression of ACLY and ACLY-3KQ could promote the proliferation and invasion of MCF7 cells (all P<0.05) , while SEV, overexpression of SIRT2 or knockdown of ACLY showed the opposite effects (all P<0.05) . Conclusion:Sev may inhibit the proliferation and invasion of breast cancer cells through SIRT2, which may be related to the regulation of ACLY deacetylation.

Research progress of histone acetylation in prevention and treatment of heart failure and new ideas based on traditional Chinese medicine / 中国中药杂志

Chronic heart failure(CHF) has become a worldwide public health problem due to its high morbidity and mortality, which seriously endangers people's lifespan and quality of life. In recent years, the treatment strategy of CHF has shifted its emphasis on short-term improvement and transformation of hemodynamics to long-term repair as well as improvement of the biological properties of heart failure. At present, with the continuous deepening of medical research, it has been found that histone acetylation is closely related to the occurrence and development of CHF. Traditional Chinese medicine, via regulating histone acetylation, delays ventricular remodeling, improves energy metabolism, inhibits fibrosis and cardiomyocyte hypertrophy, and intervenes in the development process of heart failure, thus reducing the mortality and the readmission rate and ultimately improving long-term prognosis. Therefore, this study reviewed the mechanism of histone acetylation in the treatment of heart failure as well as its prevention and treatment with traditional Chinese medicine, to provide reference for clinical treatment of CHF.

Hedgehog pathway orchestrates the interplay of histone modifications and tailors combination epigenetic therapies in breast cancer

Epigenetic therapies that cause genome-wide epigenetic alterations, could trigger local interplay between different histone marks, leading to a switch of transcriptional outcome and therapeutic responses of epigenetic treatment. However, in human cancers with diverse oncogenic activation, how oncogenic pathways cooperate with epigenetic modifiers to regulate the histone mark interplay is poorly understood. We herein discover that the hedgehog (Hh) pathway reprograms the histone methylation landscape in breast cancer, especially in triple-negative breast cancer (TNBC). This facilitates the histone acetylation caused by histone deacetylase (HDAC) inhibitors and gives rise to new therapeutic vulnerability of combination therapies. Specifically, overexpression of zinc finger protein of the cerebellum 1 (ZIC1) in breast cancer promotes Hh activation, facilitating the switch of H3K27 methylation (H3K27me) to acetylation (H3K27ac). The mutually exclusive relationship of H3K27me and H3K27ac allows their functional interplay at oncogenic gene locus and switches therapeutic outcomes. Using multiple in vivo breast cancer models including patient-derived TNBC xenograft, we show that Hh signaling-orchestrated H3K27me and H3K27ac interplay tailors combination epigenetic drugs in treating breast cancer. Together, this study reveals the new role of Hh signaling-regulated histone modifications interplay in responding to HDAC inhibitors and suggests new epigenetically-targeted therapeutic solutions for treating TNBC.

Knockdown of ACC1 promotes migration of esophageal cancer cell / 中华肿瘤杂志

Objective: To investigate the effect of acetyl-CoA carboxylase 1 (ACC1) knockdown on the migration of esophageal squamous cell carcinoma (ESCC) KYSE-450 cell and underlying mechanism. Methods: Lentiviral transfection was conducted to establish sh-NC control cell and ACC1 knocking down cell (sh-ACC1). Human siRNA HSP27 and control were transfected by Lipo2000 to get si-HSP27 and si-NC. The selective acetyltransferase P300/CBP inhibitor C646 was used to inhibit histone acetylation and DMSO was used as vehicle control. Transwell assay was performed to detect cell migration. The expression of HSP27 mRNA was examined by reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) and the expressions of ACC1, H3K9ac, HSP27 and epithelial-mesenchymal transition-related proteins E-cadherin and Vimentin were detected by western blot. Results: The expression level of ACC1 in sh-NC group was higher than that in sh-ACC1 group (P<0.01). The number of cell migration in sh-NC group was (159.00±24.38), lower than (361.80±26.81) in sh-ACC1 group (P<0.01). The protein expression levels of E-cadherin and Vimentin in sh-NC group were statistically significant compared with sh-AAC1 group (P<0.05). The migrated cell number in sh-NC+ si-NC group was (189.20±16.02), lower than (371.60±38.40) in sh-ACC1+ si-NC group (P<0.01). The migrated cell number in sh-NC+ si-NC group was higher than that in sh-NC+ si-HSP27 group (152.40±24.30, P<0.01), and the migrated cell number in sh-ACC1+ si-NC group was higher than that in sh-ACC1+ si-HSP27 group (P<0.01). The protein expression levels of E-cadherin and Vimentin in sh-NC+ si-NC group were significantly different from those in sh-ACC1+ si-NC and sh-NC+ si-HSP27 groups (P<0.01). The protein expression levels of E-cadherin and Vimentin in sh-ACC1+ si-NC group were significantly different from those in sh-ACC1+ si-HSP27 group (P<0.01). After 24 h treatment with C646 at 20 μmmo/L, the migrated cell number in sh-NC+ DMSO group was (190.80±11.95), lower than (395.80±17.10) in sh-ACC1+ DMSO group (P<0.01). The migrated cell number in sh-NC+ DMSO group was lower than that in sh-NC+ C646 group (256.20±23.32, P<0.01). The migrated cell number in sh-ACC1+ DMSO group was higher than that in sh-ACC1+ C646 group (87.80±11.23, P<0.01). The protein expressions of H3K9ac, HSP27, E-cadherin and Vimentin in sh-NC+ DMSO group were significantly different from those in sh-ACC1+ DMSO group and sh-NC+ C646 group (P<0.01). The protein expression levels of H3K9ac, HSP27, E-cadherin and Vimentin in sh-ACC1+ DMSO group were significantly different from those in sh-ACC1+ C646 group (P<0.01). Conclusion: Knockdown of ACC1 promotes the migration of KYSE-450 cell by up-regulating HSP27 and increasing histone acetylation.

SIRT1 activation synergizes with FXR agonism in hepatoprotection via governing nucleocytoplasmic shuttling and degradation of FXR

Farnesoid X receptor (FXR) is widely accepted as a promising target for various liver diseases; however, panels of ligands in drug development show limited clinical benefits, without a clear mechanism. Here, we reveal that acetylation initiates and orchestrates FXR nucleocytoplasmic shuttling and then enhances degradation by the cytosolic E3 ligase CHIP under conditions of liver injury, which represents the major culprit that limits the clinical benefits of FXR agonists against liver diseases. Upon inflammatory and apoptotic stimulation, enhanced FXR acetylation at K217, closed to the nuclear location signal, blocks its recognition by importin KPNA3, thereby preventing its nuclear import. Concomitantly, reduced phosphorylation at T442 within the nuclear export signals promotes its recognition by exportin CRM1, and thereby facilitating FXR export to the cytosol. Acetylation governs nucleocytoplasmic shuttling of FXR, resulting in enhanced cytosolic retention of FXR that is amenable to degradation by CHIP. SIRT1 activators reduce FXR acetylation and prevent its cytosolic degradation. More importantly, SIRT1 activators synergize with FXR agonists in combating acute and chronic liver injuries. In conclusion, these findings innovate a promising strategy to develop therapeutics against liver diseases by combining SIRT1 activators and FXR agonists.

Epigenetic regulation and retinal degenerative diseases / 中华实验眼科杂志

Epigenetics pertains to heritable alterations in gene expression when the nucleotide sequence remains unchanged.Epigenetic regulation mechanisms are diverse, among which DNA methylation, histone modification and non-coding RNA (ncRNA) regulation have been studied in depth.Epigenetic regulation is associated with a variety of human diseases.In the occurrence and development of retinal degenerative diseases, many epigenetic regulation processes such as DNA methylation, histone acetylation and ncRNA regulation have changed.DNA methylation is one of the important regulation processes in retinal degeneration.Aberrant DNA methylation patterns are associated with retinitis pigmentosa (RP), age-related macular degeneration (AMD), inflammation and oxidative stress.Histone acetylation is associated with RP, diabetic retinopathy (DR), glaucoma and retinal nerve ischemic injury.NcRNA is associated with RP, AMD, pathological angiogenesis, and DR.In this article, the application of epigenetic regulation in retinal degeneration was reviewed.

Effects of HDAC6 regulation of HSC70 acetylation level on bone loss in osteoporosis after oophorectomy / 中华内分泌外科杂志

Objective:To investigate the effects of histone deacetylase 6 (histone deacetylase 6, HDAC6) on oopherectomy (OOX) induced osteoporosis (OP) bone loss by binding to the promoter region of heat-shock protein 70 (HSC70) and regulating it’s acetylation.Methods:OP mouse model was established by using OOX methods. Then the mice were divided into sham operation group, OOX group, OOX+shHDAC6 group, OOX+shNC group and OOX+shHDAC6+shHSC70 group. The micro-CT system and Western blot experiment were used to detect the bone microscopic parameters of the mouse right femur and the protein expression levels of osteoblast-specific transcription factors. In vitro experiments, Westwen blot, alkaline phosphatase (ALP) staining and Alizarin Red S (ARS) staining were used to determine the effects of HDAC6 and HSC70 on the osteogenic differentiation of MC3T3-E1 cells. QRT-PCR was used to detect the expression levels of HDAC6 and HSC70 in tissue or cells. The relationship between HDAC6 and HSC70 was analyzed by ChIP experiment.Results:Compared with sham group, the expression of bone mineral density (BMD) , trabecular bone number (Tb. N) , trabecular thickness (Tb.th) and bone volume fraction (BV/TV) in the right femur of OOX group mice were decreased, the expression of TB. Sp was increased, protein expression of OSX and RUNX2 was increased. At the same time, compared with sham group (1±0.11) , the expression of HDAC6 was increased in OOX group (2.33±0.19) ( t=10.56, P<0.001) . Compared with pcDNA3.1-NC group, the protein level of Osterix (OSX) and runt-related transcription factor 2 (RUNX2) , ALP activity and mineralized area in pcDNA3.1-HDAC6 group were decreased (all P<0.05) . ChIP analysis showed that compared with the pcDNA3.1-NC group (5.26±0.47) , the acetylation level of the HSC70 promoter region in the pcDNA3.1-HDAC6 group (2.37±0.21) was significantly reduced ( t=9.72, P<0.001) . Compared with pcDNA3.1-HDAC6 group, the expression of OSX and RUNX2, ALP activity and mineralization were increased in pcDNA3.1-HDAC6+ pcDNA3.1-HSC70 group (all P<0.05) . Compared with OOX+shHDAC6 group, the expression of OSX and RUNX2 protein, BMD, Tb.N, Tb.th and BV/TV were decreased but the expression of Tb. Sp was increased in OOX+ shHDAC6+ shHSC70 group. Conclusions:HDAC6 regulates the acetylation level of HSC70 and then affects OOX-induced OP bone loss. Inhibition of HDAC6 can significantly improve OP bone loss.

Romidepsin (FK228) improves the survival of allogeneic skin grafts through downregulating the production of donor-specific antibody via suppressing the IRE1α-XBP1 pathway / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Antibody-mediated rejection (AMR) is one of the major causes of graft loss after transplantation. Recently, the regulation of B cell differentiation and the prevention of donor-specific antibody (DSA) production have gained increased attention in transplant research. Herein, we established a secondary allogeneic in vivo skin transplant model to study the effects of romidepsin (FK228) on DSA. The survival of grafted skins was monitored daily. The serum levels of DSA and the number of relevant immunocytes in the recipient spleens were evaluated by flow cytometry. Then, we isolated and purified B cells from B6 mouse spleens in vitro by magnetic bead sorting. The B cells were cultured with interleukin-4 (IL-4) and anti-clusters of differentiation 40 (CD40) antibody with or without FK228 treatment. The immunoglobulin G1 (IgG1) and IgM levels in the supernatant were evaluated by enzyme-linked immunosorbent assay (ELISA). Quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and western blotting were conducted to determine the corresponding levels of messenger RNA (mRNA) and protein expression in cultured cells and the recipient spleens. The results showed that FK228 significantly improved the survival of allogeneic skin grafts. Moreover, FK228 inhibited DSA production in the serum along with the suppression of histone deacetylase 1 (HADC1) and HDAC2 and the upregulation of the acetylation of histones H2A and H3. It also inhibited the differentiation of B cells to plasma cells, decreased the transcription of positive regulatory domain-containing 1 (Prdm1) and X-box-binding protein 1 (Xbp1), and decreased the expression of phosphorylated inositol-requiring enzyme 1 α (p-IRE1α), XBP1, and B lymphocyte-induced maturation protein-1 (Blimp-1). In conclusion, FK228 could decrease the production of antibodies by B cells via inhibition of the IRE1α-XBP1 signaling pathway. Thus, FK228 is considered as a promising therapeutic agent for the clinical treatment of AMR.

Emerging role of protein modification in inflammatory bowel disease / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The onset of inflammatory bowel disease (IBD) involves many factors, including environmental parameters, microorganisms, and the immune system. Although research on IBD continues to expand, the specific pathogenesis mechanism is still unclear. Protein modification refers to chemical modification after protein biosynthesis, also known as post-translational modification (PTM), which causes changes in the properties and functions of proteins. Since proteins can be modified in different ways, such as acetylation, methylation, and phosphorylation, the functions of proteins in different modified states will also be different. Transitions between different states of protein or changes in modification sites can regulate protein properties and functions. Such modifications like neddylation, sumoylation, glycosylation, and acetylation can activate or inhibit various signaling pathways (e.g., nuclear factor-‍κB (NF-‍κB), extracellular signal-regulated kinase (ERK), and protein kinase B (AKT)) by changing the intestinal flora, regulating immune cells, modulating the release of cytokines such as interleukin-1β (IL-‍‍1β), tumor necrosis factor-α (TNF‍-‍α), and interferon-‍γ (IFN-‍γ), and ultimately leading to the maintenance of the stability of the intestinal epithelial barrier. In this review, we focus on the current understanding of PTM and describe its regulatory role in the pathogenesis of IBD.

Acetylation of Rehmannia glutinosa polysaccharides and antioxidant activity of acetylated derivatives / 中国中药杂志

This study aims to acetylate Rehmannia glutinosa polysaccharides by acetic anhydride method, optimize process parameters and evaluate their antioxidant activity. With the degree of substitution(D_s) as a criterion, the effects of reaction time, acetic anhydride-to-polysaccharides ratio and temperature were investigated. Process parameters were optimized by single-factor experiment and response surface methodology. The infrared spectroscopy(IR) and scanning electron microscopy(SEM) proved the successful acetylation and were employed to preliminarily analyze the structural characteristics of acetylated derivatives. The results showed that the D_s was 0.327 under the optimal technological conditions, including m(acetic anhydride):m(R. glutinosa polysaccharides)=2.70, reaction time 3.0 h and temperature 48 ℃. Further, the antioxidant properties of acetylated derivatives were investigated in vitro and acetylation was found effective to improve the antioxidant activity of R. glutinosa polysaccharides. This study provides a reference for the further development and application of R. glutinosa polysaccharides.

Role of acetylation modification of host proteins in tuberculosis / 中华微生物学和免疫学杂志

Post-translational modification of host proteins induced by pathogenic microorganism plays a critical role in the development, treatment and prevention of diseases. Mycobacterium tuberculosis ( Mtb) is an intracellular pathogen that causes tuberculosis. The post-translational modification induced by Mtb infection is essential in the development and progression of tuberculosis. In recent years, it has been found that Mtb-induced host protein acetylation plays an important role in the regulation of host immunity against tuberculosis, which significantly affects the development of tuberculosis. This review focused on the role and mechanism of Mtb in regulating host protein acetylation, aiming to provide reference for future investigation on potential immunotherapy for tuberculosis.

Changes and significance of granulocyte-like myeloid-derived suppressor cells during acute phase of Kawasaki disease / 中华微生物学和免疫学杂志

Objective:To investigate the changes and significance of granulocyte-like myeloid-derived suppressor cells (G-MDSC) in the acute phage of Kawasaki disease (KD).Methods:Forty-two children with acute KD were enrolled in the present study and 32 age-matched healthy children were selected as control group. The proportion of HLA-DR -CD11b + CD33 + CD14 -CD15 + G-MDSC, the concentration of reactive oxygen species (ROS) and the expression of arginase-1 (Arg-1), programmed death-ligand 1 (PD-L1), cytotoxic T lymphocyte associated protein 4 (CTLA4), glycoprotein 130 (gp130) and phosphorylated signal transducer and activator of transcription 3 (pSTAT3) at protein level were detected by flow cytometry. Quantitative real-time PCR was used to measure the expression of inducible nitric oxide synthase (iNOS), interferon regulatory factor 8 (IRF-8), IL-6 receptor α subunit (IL-6Rα), granulocyte colony-stimulating factor receptor (G-CSFR), CCAAT/enhancer binding protein β (C/EBPβ), suppressor of cytokine signaling 1 (SOCS1) and SOCS3 at mRNA level in G-MDSC. Chromatin immunoprecipitation was performed to detect the acetylation of histone H3 at the promoters of SOCS1 and SOCS3 genes. Plasma concentrations of IL-6 and granulocyte colony-stimulating factor (G-CSF) and protein levels of IL-10, transforming growth factor-β (TGF-β) and nitric oxide (NO) in the culture supernatant of G-MDSC stimulated with LPS were measured by ELISA. Results:(1) Compared with the control group, the proportion of HLA-DR -CD11b + CD33 + CD14 -CD15 + G-MDSC as well as the concentration of ROS and the expression of inhibitory molecules (Arg-1, PD-L1 and CTLA4) in G-MDSC increased significantly in patients with acute KD ( P<0.05). Moreover, the concentrations of IL-10 and TGF-β in culture supernatant of G-MDSC were also higher than those of the control group after stimulation with lipopolysaccharide for 48 h ( P<0.05). All of the seven afore-mentioned indexes in KD patients with coronary artery lesion (CAL group ) were lower than those in patients without coronary artery lesion (NCAL group) ( P<0.05), and restored to some extent after IVIG therapy ( P<0.05). There were no statistical differences in iNOS expression or NO concentration in culture supernatant of G-MDSC among different groups ( P<0.05). (2) Plasma concentrations of IL-6 and G-CSF, and the expression of IL-6Rα, gp130, G-CSFR, pSTAT3 and C/EBPβ increased remarkably during acute phase of KD ( P<0.05). The expression of IRF-8 at transcription level in patients with acute KD was found to be lower than that of healthy controls ( P<0.05), and restored significantly after IVIG therapy ( P<0.05). Moreover, the plasma concentrations of IL-6 and G-CSF and the expression of IL-6Rα, gp130, G-CSFR and IRF-8 in the CAL group were higher than those in the NCAL group ( P<0.05), while the expression of pSTAT3 and C/EBPβ was lower in the CAL group ( P<0.05), which were restored by IVIG therapy ( P<0.05). (3) In patients with acute KD, the expression of SOCS1 and SOCS3 at mRNA level and histone acetylation at the promoters of SOCS1 and SOCS3 genes were reduced significantly in comparison with those in healthy controls ( P<0.05) , but were increased remarkably after IVIG treatment( P<0.05). The four indexes were higher in the CAL group than in the NCAL group ( P<0.05). Pearson correlation analysis showed the expression of SOCS1 and SOCS3 was negatively correlated with the protein level of pSTAT3 in G-MDSC of patients with acute KD ( r=-0.46 and -0.32, P<0.05). Conclusions:Changes in the number and function of G-MDSC caused by aberrant histone acetylation at SOCS1 and SOCS3 genes might contribute to the immune dysfunction and vascular damage in patients with KD.

Histone deacetylase inhibitors inhibit cervical cancer growth through Parkin acetylation-mediated mitophagy

Parkin, an E3 ubiquitin ligase, plays a role in maintaining mitochondrial homeostasis through targeting damaged mitochondria for mitophagy. Accumulating evidence suggests that the acetylation modification of the key mitophagy machinery influences mitophagy level, but the underlying mechanism is poorly understood. Here, our study demonstrated that inhibition of histone deacetylase (HDAC) by treatment of HDACis activates mitophagy through mediating Parkin acetylation, leading to inhibition of cervical cancer cell proliferation. Bioinformatics analysis shows that Parkin expression is inversely correlated with HDAC2 expression in human cervical cancer, indicating the low acetylation level of Parkin. Using mass spectrometry, Parkin is identified to interact with two upstream molecules, acetylase acetyl-CoA acetyltransferase 1 (ACAT1) and deacetylase HDAC2. Under treatment of suberoylanilide hydroxamic acid (SAHA), Parkin is acetylated at lysine residues 129, 220 and 349, located in different domains of Parkin protein. In in vitro experiments, combined mutation of Parkin largely attenuate the interaction of Parkin with PTEN induced putative kinase 1 (PINK1) and the function of Parkin in mitophagy induction and tumor suppression. In tumor xenografts, the expression of mutant Parkin impairs the tumor suppressive effect of Parkin and decreases the anticancer activity of SAHA. Our results reveal an acetylation-dependent regulatory mechanism governing Parkin in mitophagy and cervical carcinogenesis, which offers a new mitophagy modulation strategy for cancer therapy.

A network pharmacology-based strategy for predicting the protective mechanism of Ginkgo biloba on damaged retinal ganglion cells / 中国天然药物

Hallmarks of the pathophysiology of glaucoma are oxidative stress and apoptotic death of retinal ganglion cells (RGCs). Ginkgo biloba extract (EGb) with multi-target, multi-pathway functions has been reported to exert positive pharmacological effects on oxidative stress and damaged RGCs. However, the ingredients and anti-apoptotic targets of EGb in the treatment of open-angle glaucoma (OAG) have not been fully elucidated. Therefore, in-depth analysis is necessary for further research. Ginkgo biloba-related and anti-apoptotic targets were identified and then combined to obtain the intersection, representing the potential anti-apoptotic targets of Ginkgo biloba. In addition, compound-anti-apoptotic target and OAG-target protein-protein interaction network were merged to obtain five core genes and compound-OAG-anti-apoptotic target protein-protein interaction network. Consequently, the active compounds and anti-apoptotic targets of Ginkgo biloba in the treatment of OAG were identified, namely luteolin, β-sitosterol, kaempferol, stigmasterol, quercetin, and p53, Bax, Bcl-2, Caspase-3 and Caspase-9, respectively. For the anti-apoptotic targets of Ginkgo biloba in the treatment of OAG, Gene Ontology (GO) and pathway analysis were executed to confirm the gene functions of Ginkgo biloba in antagonizing apoptosis of RGCs. The pathway enrichment was mainly involved in transcriptional activation of p53 responsive genes, activation of caspases and apoptotic processes. Finally, we confirmed the results of the network analysis by H2O2 treated RGC-5 cells in vitro. The results demonstrated that EGb protection can effectively diminish H2O2-induced apoptosis by inhibiting p53 acetylation, reducing the ratio of Bax/Bcl-2 and suppressing the expression of specific cleavage of Caspase-9 and Caspase-3.

Coactivator p300-induced H3K27 acetylation mediates lipopolysaccharide-induced inflammatory mediator synthesis / 南方医科大学学报

OBJECTIVE@#To investigate the role of acetylated modification induced by coactivator p300 in lipopolysaccharide (LPS)- induced inflammatory mediator synthesis and its molecular mechanism.@*METHODS@#Agilent SurePrint G3 Mouse Gene Expression V2 microarray chip and Western blotting were used to screen the molecules whose expression levels in mouse macrophages (RAW246.7) were correlated with the stimulation intensity of LPS. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (chip-qPCR) were used to verify the binding of the molecules to the promoters of IL-6 and TNF-α genes. The effects of transfection of RAW246.7 cells with overexpression or interfering plasmids on IL-6 and TNF-α synthesis were evaluated with ELISA, and the binding level of the target molecules and acetylation level of H3K27 in the promoter region of IL-6 and TNF-α genes were analyzed by chromatin immunoprecipitation sequencing technique (chip-seq).@*RESULTS@#Gene microarray chip data and Western blotting both confirmed a strong correlation of p300 expression with the stimulation intensity of LPS. Immunocoprecipitation confirmed the binding between p300 and c-myb. The results of EMSA demonstrated that c-myb (P < 0.05), but not p300, could directly bind to the promoter region of IL-6 and TNF-α genes; p300 could bind to the promoters only in the presence of c-myb (P < 0.05). The expressions of p65, p300 and c-myb did not show interactions. Both p300 overexpression and LPS stimulation could increase the level of promoter-binding p300 and H3K27 acetylation level, thus promoting p65 binding and inflammatory gene transcription; such effects were obviously suppressed by interference of c-myb expression (P < 0.05). Interference of p65 resulted in inhibition of p65 binding to the promoters and gene transcription (P < 0.05) without affecting p300 binding or H3K27 acetylation level.@*CONCLUSION@#LPS can stimulate the synthesis of p300, whose binding to the promoter region of inflammatory genes via c-myb facilitates the cohesion of p65 by inducing H3K27 acetylation, thus promoting the expression of the inflammatory genes.

Effect of diallyl trisulfide on the expression of folate receptor α in human gastric cancer cell lines BGC823 and AGS and the related regulatory mechanism / 肿瘤研究与临床

Objective:To investigate the effect of diallyl trisulfide (DATS) on the expression of folate receptor α (FRα) in human gastric cancer cells and the related regulatory mechanism.Methods:Human gastric cancer cell lines BGC823 and AGS were selected, BGC823 cells were treated with 10, 20, 40, 80 μmol/L DATS for 48 hours, and AGS cells were treated with 5, 10, 20, 40 μmol/L DATS for 48 hours. Cells treated with 6 μmol/L histone deacetylase (HDAC) inhibitor trichostatin A (TSA) were used as positive control for epigenetic study, and cells untreated with DATS were used as negative control. The apoptosis of gastric cancer cells induced by DATS was detected by flow cytometry. After BGC823 and AGS cells were treated by DATS for 48 hours, they were replaced with DATS-free cell culture medium and cultured for different time to detect the changes in FRα protein expression. BGC823 and AGS cells were treated with 6 μmol/L TSA or 40 μmol/L DATS. The protein expression levels of FRα, HDAC1 and HDAC2, and histone H3 lysine 9 acetylation (H3K9ac) and histone H4 lysine 5 acetylation (H4K5ac) were detected by Western blot. BGC823 cells were inoculated into BALB/c nude mice to establish tumor bearing model. The nude mice in DATS group were injected intraperitoneally with 10 mg/kg DATS for 16 days, and then the protein in tumor-bearing tissues was extracted to detect the expression of target protein, while the control group was injected with equal dose of 0.9% NaCl solution.Results:The expressions of FRα protein in BGC823 and AGS cells were up-regulated in a dose-dependent way after gradient concentrations of DATS treatment ( F = 65.68, P < 0.01; F = 26.65, P < 0.01). After changing the cell culture medium without DATS, the expressions of FRα protein in BGC823 and AGS cells gradually decreased and returned to the initial levels ( F = 74.57, P < 0.01; F = 30.92, P < 0.01). With the increase of DATS concentration, the apoptosis rates of BGC823 and AGS cells increased ( F = 32.95, P < 0.01; F = 38.97, P < 0.01). After TSA treatment, FRα protein expressions in BGC823 and AGS cells were up-regulated by 4.5 times ( t = -12.62, P < 0.01) and 3.6 times ( t = -10.00, P < 0.01). After 40 μmol/L and 20 μmol/L DATS treatment, the expression level of FRα protein in BGC823 and AGS cells was up-regulated (both P < 0.01), the expressions of HDAC1 and HDAC2 were inhibited (all P < 0.01), and the levels of H3K9ac and H4K5ac acetylation modification increased (all P < 0.01). The results of tumor-bearing nude mice experiment showed that the volume of transplanted tumor in DATS group was smaller than that in the control group [(214±39) mm 3 vs. (577±98) mm 3], and the difference was statistically significant ( t = 4.86, P < 0.01). Compared with the control group, FRα protein expression in the transplanted tumor tissues of DATS group was up-regulated about 2 times ( t = -5.29, P < 0.01), and the expression levels of HDAC1 and HDAC2 proteins were down-regulated ( t = 9.36, P < 0.01; t = 9.88, P < 0.01). Conclusions:DATS up-regulates the expression of FRα protein in human gastric cancer BGC823 and AGS cells in a dose-dependent and reversible manner. The mechanism may be related to the effect of DATS on histone acetylation modification in tumor cells.

Relationship between SIRT1 and STAT3 acetylation during high glucose-induced cardiac microvascular endothelial cell injury / 中华麻醉学杂志

Objective:To evaluate the relationship between silence information regulator 1 (SIRT1) and signal transducers and activators of transcription 3 (STAT3) acetylation during high glucose-induced cardiac microvascular endothelial cell injury.Methods:Cardiac microvascular endothelial cells of Sprague-Dawley rats were cultured.The cells at the logarithmic growth phase were selected and divided into 3 groups ( n=24 each) using a random number table method: control group (C group), high glucose group (HG group) and high glucose+ SIRT1 agonist SRT1720 group (HG+ SRT group). The cardiac microvascular endothelial cells were seeded in a 6- or 96-well cell culture plate at a density of 2×10 5 cells/ml.When the cell density reached 50%, the culture medium was then replaced with high-glucose (glucose 33 mmol/L) DMEM culture medium containing with 10% fetal bovine serum and 1% double antibody in HG and HG+ SRT groups.In group HG+ SRT, 20 μmol/L SRT1720 was added simultaneously, and the cells were cultured at 37 ℃ in an incubator with 5% CO 2 for 24 h. The cell viability was determined by CCK-8 assay, the activity of superoxide dismutase (SOD) was detected using a spectrophotometer, the levels of lactic dehydrogenase (LDH), interleukin-6 (IL-6) and tumor necrosis factor-β (TNF-β) in the supernatant were detected by enzyme-linked immunosorbent assay, and the expression of SIRT1, acetylated STAT3 (ac-STAT3) and phosphorylated STAT3 (p-STAT3) was determined by Western blot. Results:Compared with C group, the cell viability and SOD activity were significantly decreased, levels of LDH, IL-6 and TNF-β in the supernatant were increased, expression of SIRT1 was down-regulated, and expression of ac-STAT3 and p-STAT3 was up-regulated in group HG and group HG+ SRT ( P<0.05). Compared with group HG, the cell viability and SOD activity were significantly increased, levels of LDH, IL-6 and TNF-β in the supernatant were decreased, expression of SIRT1 was up-regulated, and expression of ac-STAT3 and p-STAT3 was down-regulated in group HG+ SRT ( P<0.05). Conclusion:SIRT1 can alleviate high glucose-induced cardiac microvascular endothelial cell injury by promoting STAT3 deacetylation.

Effects of brain-specific knockout of Sirt6 gene on cerebral cortex in aged mice / 中华行为医学与脑科学杂志

Objective:To study the effect of senescence gene silent information regulator 6 (Sirt6) knockout on the brain of aged mice.Methods:Sirt6-flox transgenic mice were constructed, and the mouse brain tissue was specifically knocked out by Emx1-Cre tool mice.According to genotyping, 11 wild-type mice were selected as control group(WT group) and 10 Sirt6 gene konckout mice were selected as conditional knockout group(cKO group). Body size and body weight of the aged mice were measured and cerebral cortex thickness was measured by HE staining.Brain neurogenesis was analyzed with EdU markers.The expression of RNA-binding protein HuR and apoptosis-related protein Caspase-3 were detected by Western blot.Meanwhile, histone acetylation levels in the cortex were detected.Results:Sirt6 brain tissue-specific knocked out mice were successfully constructed.Compared with the brain tissue area((2.07±0.22) cm 2)and cortical thickness ((970.56±80.91) μm) of WT mice in the 12-month-old group, the brain tissue area ((1.61±0.14)cm 2) and cortical thickness ((822.88±53.94) μm) in Sirt6 cKO group were smaller, and the differences were statistically significant (both P<0.05). EdU incorporation into nerve cells showed that the number of EdU incorporation into periventricular nerve cells in cKO group was lower ((4.75±1.48)) than that in WT group ((10.29±1.93)). The difference was statistically significant ( P<0.001). In the experiment of 17 months age group, mice in cKO group were smaller in body size, lower in body weight ((29.00±1.08) g) and smaller in brain area ((1.54±0.55)cm 2)compared with WT group in body size, body weight ((35.25±4.17) g) and brain tissue area ((1.98±0.18) cm 2)(both P<0.05). The expression of Caspase-3 and HuR in cortical proteins of these two age groups decreased( t=2.95, 5.38, both P<0.05), and the expression of H3K9ac and H3K56ac increased( t=3.53, 2.78, both P<0.05), but the expression of Sirt1 homologous gene remained unchanged( t=1.26, P>0.05). Conclusion:The specific deletion of Sirt6 in brain tissue can lead to the decrease of brain neurogenesis in aged mice, and the aggravation of aging and the increase of apoptosis, which may be the reason for the thinning of cerebral cortex and brain tissue atrophy.The molecular mechanism is speculated to be related to the increase of acetylation level after Sirt6 knockout

Effects of oleanolic acid on early brain injury after subarachnoid hemorrhage through SIRT1 / 国际生物医学工程杂志

Objective:To investigate the effect of oleanolic acid (OA) on Sirtuin1 (SIRT1)-mediated high-mobility group box 1(HMGB1) deacetylation in the early brain injury after subarachnoid hemorrhage (SAH).Methods:A total of 176 male Sprague-Dawley rats were randomly divided into Sham operation (Sham group) ( n=48), SAH group ( n=48), OA group ( n=48) and Sirtinol group ( n=32). Rats in the SAH group, OA group and the Sirtinol group all adopted internal carotid artery puncture to construct SAH model, while rats in the sham group did not adopt puncture. One hour after modeling, the rats in the OA group were given intraperitoneal injection of OA (20 mg/kg), and the rats in the Sirtinol group were given intracerebroventricular injection of Sirtinol (2 mmol/L, 30 μL/kg). The rats in the sham group and SAH group were injected with equal volumes of sodium chloride injection. The SAH score and neurological score were performed 24 h after SAH, and the water content in the brain tissue and Evans blue exudation rate were measured. The expressions of HMGB1, SIRT1 and acetylated HMGB1 proteins in the brain tissue of rats were detected by Western Blot. The expression of HMGB1 mRNA in the brain of the rats was detected by quantitative real-time PCR. The distribution of HMGB1 protein in the brain of the rats was observed by immunofluorescence staining. TUNEL staining was used to observe the neuronal apoptosis in the brain tissue of the rats. Results:Compared with the SAH group, the SAH score of the OA group was significantly reduced ( P<0.001), the Garcia score was increased ( P<0.01), and the brain water content and Evans blue exudation rate were both reduced (all P<0.01). Compared with the OA group, the SAH score of the Sirtinol group was increased ( P<0.01), the Garcia score was significantly decreased ( P<0.001), and the brain water content and Evans blue exudation rate were both increased (all P<0.01). The results of Western Blot and real-time fluorescent quantitative PCR showed that, compared with the SAH group, the protein level ( P<0.01) and mRNA level ( P<0.05) of HMGB1 in the OA group were decreased, the expression of SIRT1 protein was significantly increased ( P<0.001), and the expression of acetylated HMGB1 protein was decreased ( P<0.01). Immunofluorescence staining showed that OA inhibited the migration of HMGB1 protein from the nucleus to the cytoplasm. TUNEL staining showed that OA could effectively reduce the number of TUNEL-positive cells. Compared with the OA group, Sirtinol significantly increased the number of TUNEL-positive cells. Conclusions:OA can reduce the release of HMGB1 through the SIRT1/HMGB1 pathway, thereby protecting the early brain injury after SAH.

Prospects for histone deacetylase inhibitors as antidepressants / 药学学报

Depression is a serious mental illness with a high incidence. At present, we do not fully understand the specific pathological mechanisms of depression, and the efficacy of drug treatments is very limited. Recent studies have shown that epigenetic changes that occur in specific brain regions may be a key mechanism by which environmental factors to interact with individuals to influence the risk of depression. Therefore, drugs that target epigenetic regulation may become a new direction for the development of antidepressants. Histone deacetylase inhibitors (HDACi) are a class of compounds that inhibit histone deacetylase activity, which has been reported to be associated with depression; this article addresses the use of HDACi in preclinical studies, and their potential therapeutic role and limitations of use in depression.