Hepatic steatosis is associated with dysregulated cholesterol metabolism and altered protein acetylation dynamics in chickens

Background Hepatic steatosis is a prevalent manifestation of fatty liver, that has detrimental effect on the health and productivity of laying hens, resulting in economic losses to the poultry industry. Here, we aimed to systematically investigate the genetic regulatory mechanisms of hepatic steatosis in laying hens.Methods Ninety individuals with the most prominent characteristics were selected from 686 laying hens according to the accumulation of lipid droplets in the liver, and were graded into three groups, including the control, mild hepatic steatosis and severe hepatic steatosis groups. A combination of transcriptome, proteome, acetylome and lipidome analyses, along with bioinformatics analysis were used to screen the key biological processes, modifications and lipids associated with hepatic steatosis.Results The rationality of the hepatic steatosis grouping was verified through liver biochemical assays and RNA-seq. Hepatic steatosis was characterized by increased lipid deposition and multiple metabolic abnormalities. Integration of proteome and acetylome revealed that differentially expressed proteins(DEPs) interacted with differentially acetylated proteins(DAPs) and were involved in maintaining the metabolic balance in the liver. Acetylation alterations mainly occurred in the progression from mild to severe hepatic steatosis, i.e., the enzymes in the fatty acid oxidation and bile acid synthesis pathways were significantly less acetylated in severe hepatic steatosis group than that in mild group(P < 0.05). Lipidomics detected a variety of sphingolipids(SPs) and glycerophospholipids(GPs) were negatively correlated with hepatic steatosis(r ≤-0.5, P < 0.05). Furthermore, the severity of hepatic steatosis was associated with a decrease in cholesterol and bile acid synthesis and an increase in exogenous cholesterol transport.Conclusions In addition to acquiring a global and thorough picture of hepatic steatosis in laying hens, we were able to reveal the role of acetylation in hepatic steatosis and depict the changes in hepatic cholesterol metabolism. The findings provides a wealth of information to facilitate a deeper understanding of the pathophysiology of fatty liver and contributes to the development of therapeutic strategies.

IL-17 induces NSCLC cell migration and invasion by elevating MMP19 gene transcription and expression through the interaction of p300-dependent STAT3-K631 acetylation and its Y705-phosphorylation

The cancer cell metastasis is a major death reason for patients with non-small cell lung cancer(NSCLC).Although researchers have disclosed that interleukin 17(IL-17)can increase matrix metalloproteinases(MMPs)induction causing NSCLC cell metastasis,the underlying mechanism remains unclear.In the study,we found that IL-17 receptor A(IL-17RA),p300,p-STAT3,Ack-STAT3,and MMP19 were up-regulated both in NSCLC tissues and NSCLC cells stimulated with IL-17.p300,STAT3 and MMP19 overexpression or knockdown could raise or reduce IL-17-induced p-STAT3,Ack-STAT3 and MMP19 level as well as the cell migration and invasion.Mechanism investigation revealed that STAT3 and p300 bound to the same region(−544 to−389 nt)of MMP19 promoter,and p300 could acetylate STAT3-K631 elevating STAT3 transcriptional activity,p-STAT3 or MMP19 expression and the cell mobility exposed to IL-17.Meanwhile,p300-mediated STAT3-K631 acetylation and its Y705-phosphorylation could interact,synergistically facilitating MMP19 gene transcription and enhancing cell migration and invasion.Besides,the animal experiments exhibited that the nude mice inoculated with NSCLC cells by silencing p300,STAT3 or MMP19 gene plus IL-17 treatment,the nodule number,and MMP19,Ack-STAT3,or p-STAT3 production in the lung metastatic nodules were all alleviated.Collectively,these outcomes uncover that IL-17-triggered NSCLC metastasis involves up-regulating MMP19 expression via the interaction of STAT3-K631 acetylation by p300 and its Y705-phosphorylation,which provides a new mechanistic insight and potential strategy for NSCLC metastasis and therapy.

Enhanced autophagic clearance of amyloid-βvia histone deacetylase 6-mediated V-ATPase assembly and lysosomal acidification protects against Alzheimer's disease in vitro and in vivo

Recent studies have suggested that abnormal acidification of lysosomes induces autophagic accumulation of amyloid-βin neurons,which is a key step in senile plaque formation.Therefore,resto ring normal lysosomal function and rebalancing lysosomal acidification in neurons in the brain may be a new treatment strategy for Alzheimer's disease.Microtubule acetylation/deacetylation plays a central role in lysosomal acidification.Here,we show that inhibiting the classic microtubule deacetylase histone deacetylase 6 with an histone deacetylase 6 shRNA or thehistone deacetylase 6 inhibitor valproic acid promoted lysosomal reacidification by modulating V-ATPase assembly in Alzheimer's disease.Fu rthermore,we found that treatment with valproic acid markedly enhanced autophagy.promoted clearance of amyloid-βaggregates,and ameliorated cognitive deficits in a mouse model of Alzheimer's disease.Our findings demonstrate a previously unknown neuroprotective mechanism in Alzheimer's disease,in which histone deacetylase 6 inhibition by valproic acid increases V-ATPase assembly and lysosomal acidification.

Relationship between histone acetylation/deacetylation and gene transcription

In eukaryotes, nucleosome is the basic unit of chromatin. Nucleosome is composed of an octamer of histone proteins (two molecules each of histones H 2A , H 2B , H 3 and H 4) and DNA strand wound around the octamer. Some data show that core histone octamer can affect gene transcription both \%in vitro\% and \%in vivo.\% Recent results indicate that histone acetylation/deacetylation is a key step to regulate activity of genes. This article summarizes some coactivators, such as GCN5p, P300/CBP and TAF Ⅱ 250, which are recently found to have histone acetyltransferase activity. The relationship between these coactivators and gene activation is also described. Besides, this article concerns some corepressors which have histone deacetylase activity, such as Rpd3p, HDAC2. These corepressors combine with other protein complex and then repress transcription. Finally, some problems to be solved and the future direction in this active field are discussed.

A Highly Regioselective Deacetylation of Taxanes

A highly regioselective O-deacetylation of taxanes at C-5 position was accomplished by treatment with t-BuOK and a possible mechanism was proposed.

SUMOylation and deacetylation affect NF-κB p65 activity induced by high glucose in human lens epithelial cells

AIM: To explore the effects of IκBα SUMOylation and NF-κB p65 deacetylation on NF-κB p65 activity induced by high glucose in cultured human lens epithelial cells(HLECs).METHODS: HLECs(SRA01/04) were cultured with 5.5, 25, and 50 mmol/L glucose media for 24 h, and with 50 mmol/L glucose media for 0, 12, and 24 h respectively. SUMO1 and SIRT1 expressions were detected by reverse transcriptionpolymerase chain reaction(RT-PCR) and Western blot(WB). IκBα and NF-κB p65 expressions were detected by WB. With NAC, DTT, MG132 or Resveratrol(RSV) treatment, SUMO1 and SIRT1 expressions were detected by WB. Protein expression localizations were examined by immunofluorescence and co-immunofluorescence. The effects of SUMO1 or SIRT1 overexpression, as well as MG132 and RSV, on the nuclear expression and activity of IκBα and NF-κB p65 were analyzed by immunoblot and dual luciferase reporter gene assay.RESULTS: SUMO1 and SIRT1 expressions were influenced by high glucose in mRNA and protein levels, which could be blocked by NAC or DTT. SUMO1 was down-regulated by using MG132, and SIRT1 was up-regulated under RSV treatment. IκBα nuclear expression was attenuated and NF-κB p65 was opposite under high glucose, while IκBα and NF-κB p65 location was transferred to the nucleus. SUMO1 or SIRT1 overexpression and MG132 or RSV treatment affected the nuclear expression and activity of IκBα and NF-κB p65 under high glucose condition.CONCLUSION: IκBα SUMOylation and NF-κB p65 deacetylation affect NF-κB p65 activity in cultured HLECs under high glucose, and presumably play a significant role in controlling diabetic cataract.

HDACs,histone deacetylation and gene transcription: from molecular biology to cancer therapeutics

Histone deacetylases （HDACs） and histone acetyl transferases （HATs） are two counteracting enzyme families whose enzymatic activity controls the acetylation state of protein lysine residues, notably those contained in the N-terminal extensions of the core histones. Acetylation of histones affects gene expression through its influence on chromatin conformation. In addition, several non-histone proteins are regulated in their stability or biological function by the acetylation state of specific lysine residues. HDACs intervene in a multitude of biological processes and are part of a multiprotein family in which each member has its specialized functions. In addition, HDAC activity is tightly controlled through targeted recruitment, protein-protein interactions and post-translational modifications. Control of cell cycle progression, cell survival and differentiation are among the most important roles of these enzymes. Since these processes are affected by malignant transformation, HDAC inhibitors were developed as antineoplastic drugs and are showing encouraging efficacy in cancer patients.

Neuroprotective mechanisms ofε-viniferin in a rotenone-induced cell model of Parkinson's disease:significance of SIRT3-mediated FOXO3 deacetylation

Trans-(-)-ε-viniferin(ε-viniferin)has antioxidative and anti-inflammatory effects.It also has neuroprotective effects in Huntington's disease by activating the SIRT3/LKB1/AMPK signaling pathway;however,it remains unknown whetherε-viniferin also has a neuroprotective role in Parkinson's disease.A Parkinson's disease cell model was induced by exposing SH-SY5 Y cells to 3.0μM rotenone for 24 hours,and cells were then treated with 1.0μMε-viniferin for 24 hours.Treatment withε-viniferin upregulated SIRT3 expression,which promoted FOXO3 deacetylation and nuclear localization.ε-Viniferin also increased ATP production and decreased reactive oxygen species production.Furthermore,ε-viniferin treatment alleviated rotenone-induced mitochondrial depolarization and reduced cell apoptosis,and restored the expression of mitochondrial homeostasis-related proteins.However,when cells were transfected with SIRT3 or FOXO3 shRNA prior to rotenone andε-viniferin treatment,these changes were reversed.The results from the present study indicate thatε-viniferin enhances SIRT3-mediated FOXO3 deacetylation,reduces oxidative stress,and maintains mitochondrial homeostasis,thus inhibiting rotenone-induced cell apoptosis.ε-Viniferin may therefore be a promising treatment strategy for Parkinson's disease.

An Efficient One-step Methyl Esterification of Carboxylic Acid and Deacetylation of Alcohol under BF_3·OEt_2-MeOH

An efficient one-step methyl esterification of carboxylic acid and deacetylation of alcohol under BF3O·Et2-MeOH was developed.

Biological Properties of Chitosan Films with Different Degree of Deacetylation

Chitin and chitosan films were prepared by solution casting method. Chitosan specimens used in this study were deacetylated by 50.4%, 69.2%, 85.5% and 96.3%. Their water content, protein adhesion ability, cytocompatibility, cell adhesion ability, in vitro and vivo degradability and biocompatibility were evaluated. Results indicated that with the degree of deacetylation （DD） between 50% and 70%, the chitosan showed higher water content. The higher the DD, the stronger protein adhesion ability the chitosan had. All the films have good cytocompatibility and the films with higher DD have better cell adhesion ability. Chitin films degraded more rapidly than others, which disappeared in 2 to 4 weeks after they were implanted in subcutaneous tissue and musculature. Their inflammatory reaction became weaker as the films degraded. As the DD got higher, the films degraded slower. The films of DD 85.5% and DD 90.3% even didn＇t disappeared in 12 weeks after they were implanted. Their inflammatory reaction was mild at the beginning of degradation, and became severe in 4 to 8 weeks, then weaken at last. This basic result can be very helpful for tissue engineering.

Green Synthesis and Physical and Chemical Characterization of Chitosans with a High Degree of Deacetylation, Produced by a Binary Enzyme System

Chitosan is a biopolymer obtained from chitin, where the N-acetylglucosamine monomer is in its deacetylated form; this polymer is useful for a wide variety of industrial applications. The properties and uses of chitosan depend on its physical and chemical characteristics, which result from the treatments used for its production. In this study, we report the preparation and characterization ofchitosan oligosaccharides by a green synthesis from crystalline shrimp chitin, using a sequential enzyme treatment by chitinase and chitin deacetylase. Chitinases were purified from grapes and used to rupture the crystalline shrimp chitin structure, modifying the crystallinity index from 57.6% to 15.9%. The resultant polymers were deacetylated using a recombinant chitin deacetylase from Saccharomyces cerevisiae, which was cloned and expressed in Pichia pastoris. The chitosans produced showed an estimated DA （degree of acetylation） of approximately 20%, and the molecular weights ranged from -7,600 to -3,700 after treatment in pH 3.0 and pH 6.0 for 10 min and 40 min, respectively. Physical and chemical characterization of the products indicated that enzyme fragmentation of chitin probably makes the acetamide groups more accessible to deacetylation, forming homogeneous polymers that are free of hazardous sub-products, have defined low molecular weights, and are highly deacetylated.

Sodium butyrate alleviates deoxynivalenol-induced hepatic cholesterol metabolic dysfunction via RORγ-mediated histone acetylation modification in weaning piglets

Background:Cholesterol is an essential component of lipid rafts in cell plasma membrane,which exerts a hepatoprotective role against mycotoxin exposure in pigs,and cholesterol metabolism is vulnerable to epigenetic histone acetylation.Therefore,our present study aimed to investigate whether a histone deacetylase inhibitor(sodium butyrate [NaBu]) could protect the porcine liver from deoxynivalenol(DON) exposure by modulating cholesterol metabolism.Herein,we randomly divided 28 pigs into four groups,which were fed an uncontaminated basal diet,contaminated diet(4 mg DON/kg),uncontaminated diet supplemented with 0.2% NaBu or 4 mg/kg DON contaminated diet(4 mg DON/kg) supplemented with 0.2% NaBu for 28 d.Results:We found that the serum alanine transaminase(ALT),aspartate transaminase(AST),and alkaline phosphatase(ALP) were all increased in pigs exposed to DON,indicative of significant liver injury.Furthermore,the cholesterol content in the serum of DON-exposed pigs was significantly reduced,compared to the healthy Vehicle group.Transcriptome analysis of porcine liver tissues revealed that the cholesterol homeostasis pathway was highly enriched due to DON exposure.In which we validated by qRT-PCR and western blotting that the cholesterol program was markedly activated.Importantly,NaBu effectively restored parameters associated with liver injury,along with the cholesterol content and the expression of key genes involved in the cholesterol biosynthesis pathway.Mechanistically,we performed a ChIP-seq analysis of H3K27ac and showed that NaBu strongly diminished DON-increased H3K27ac genome-wide enrichment.We further validated that the elevated H3K27ac and H3K9ac occupancies on cholesterol biosynthesis genes were both decreased by NaBu,as determined by ChIP-qPCR analysis.Notably,nuclear receptor RORγ,a novel regulator of cholesterol biosynthesis,was found in the hyperacetylated regions.Again,a remarkable increase of RORγ at both mRNA and protein levels in DON-exposed porcine livers was drastically reduced by NaBu.Consistent with RORγ expression,NaBu also hindered RORγ transcriptional binding enrichments on these activated cholesterol biosynthesis genes like HMGCR,SQLE,and DHCR24.Furthermore,we conducted an in vitro luciferase reporter assay to verify that porcine RORγ directly bonds to the promoters of the above target genes.Conclusions:Collectively,our results demonstrate the utility of the natural product Na Bu as a potential anti-mycotoxin nutritional strategy for regulating cholesterol metabolism via RORγ-mediated histone acetylation modification.

Histone deacetylase inhibitor pracinostat suppresses colorectal cancer by inducing CDK5-Drp1 signaling-mediated peripheral mitofission

Divisions at the periphery and midzone of mitochondria are two fission signatures that determine the fate of mitochondria and cells.Pharmacological induction of excessively asymmetric mitofissionassociated cell death(MFAD)by switching the scission position from the mitochondrial midzone to the periphery represents a promising strategy for anticancer therapy.By screening a series of paninhibitors,we identified pracinostat,a pan-histone deacetylase(HDAC)inhibitor,as a novel MFAD inducer,that exhibited a significant anticancer effect on colorectal cancer(CRC)in vivo and in vitro.Pracinostat increased the expression of cyclin-dependent kinase 5(CDK5)and induced its acetylation at residue lysine 33,accelerating the formation of complex CDK5/CDK5 regulatory subunit 1 and dynaminrelated protein 1(Drp1)-mediated mitochondrial peripheral fission.CRC cells with high level of CDK5(CDK5-high)displayed midzone mitochondrial division that was associated with oncogenic phenotype,but treatment with pracinostat led to a lethal increase in the already-elevated level of CDK5 in the CRC cells.Mechanistically,pracinostat switched the scission position from the mitochondrial midzone to the periphery by improving the binding of Drp1 from mitochondrial fission factor(MFF)to mitochondrial fission 1 protein(FIS1).Thus,our results revealed the anticancer mechanism of HDACi pracinostat in CRC via activating CDK5-Drp1 signaling to cause selective MFAD of those CDK5-high tumor cells,which implicates a new paradigm to develop potential therapeutic strategies for CRC treatment.

GhHSP24.7 mediates mitochondrial protein acetylation to regulate stomatal conductance in response to abiotic stress in cotton

During seed germination,the cotton chaperone protein HSP24.7 regulates the release,from the mitochondrial electron transport chain,of reactive oxygen species(ROS),a stimulative signal regulating germination.The function of HSP24.7 during vegetative stages remains largely unknown.Here we propose that suppression of Gh HSP24.7 in cotton seedlings increases tolerance to heat and drought stress.Elevation of Gh HSP24.7 was found to be positively associated with endogenous levels of ROS.We identified a new client protein of Gh HSP24.7,cotton lysine deacetylase(Gh HDA14),which is involved in mitochondrial protein modification.Elevated levels of Gh HSP24.7 suppressed deacetylase activity in mitochondria,leading to increased acetylation of mitochondrial proteins enriched in the subunit of Ftype ATPase,V-type ATPase,and cytochrome C reductase,ultimately reducing leaf ATP content.Consequently,in combination with altered ROS content,Gh HSP24.7 transgenic lines were unable to coordinate stomatal closure under stress.The regulation circuit composed of Gh HSP24.7 and Gh HDA14 represents a post-translation level mechanism in plant abiotic stress responses that integrates the regulation of ROS and ATP.

Acetylation of Chinese bamboo flour and thermoplasticity

Chinese bamboo flour was chemically modified by acetylation with acetic anhydride by using trichloroacetic acid as an activation agent and the optimized condition for acetylation of bamboo flour was determined as the trichloroacetic acid amount 6.0 g per 1.5-g bamboo flour, ultrasosonication duration 40 min and the reaction time 1 h at 65℃. The composition, microstructure and thermal behavior of acetylated bamboo flour were preliminarily characterized by FT-IR, DSC and SEM etc. The acetylated bamboo flour can be molded into sheets at 130℃ and 10 MPa, indicating the modified bamboo flour possesses thermalplastic performance.

Cu^(2+)、前体对红豆杉细胞生长及产生10-Deacetyl Baccatin的影响

目的:研究前体和Cu2+诱导子对云南红豆杉细胞生长和产生10-去乙酰巴卡亭Ⅲ的影响。方法:在培养12d后分别向培养基中添加不同浓度的乙酸钠、苯甲酸钠两种前体和CuSO4诱导子,经过培养对云南红豆杉细胞生长情况进行统计,用HPLC测定细胞中10-去乙酰巴卡亭Ⅲ的含量。结果:培养基中添加0.1mmol/L乙酸钠和0.1mmol/L苯钾酸钠,10-去乙酰巴卡亭Ⅲ含量是不添加时的1.8倍和2.8倍,含量分别为0.079 88%、0.082 91%;B5培养基中添加0.1mg/L硫酸铜时,10-去乙酰巴卡亭Ⅲ含量是B5培养基标准含量的2.2倍。结论:确定了云南红豆杉细胞悬浮培养过程中B5培养基添加乙酸钠、苯甲酸钠和硫酸铜的最佳浓度,表明适宜浓度前体和Cu2+诱导子对10-去乙酰巴卡亭Ⅲ合成与释放有显著影响。

UPLC测定紫金龙中8-deacetyl-yunaconitine的含量

目的建立紫金龙药材中8-deacetyl-yunaconitine的含量测定方法,为其质量标准的建立提供科学依据。方法于2015年1—6月,选择贵州不同产地紫金龙药材21批,采用超高液相色谱（UPLC）的方法,色谱柱Agilent Eclipse XDB-C18柱,流动相为乙腈-0.1%醋酸铵,梯度洗脱,流速1.0 m L/min,检测波长254 nm。记录8-deacetyl-yunaconitine的色谱峰面积。结果测定了21批不同产地的紫金龙药材,8-deacetyl-yunaconitine含量在0.054%~0.250%。平均回收率为99.6%,RSD为0.6%。结论该方法简便、快速、准确、重复性好,可以控制该药材的质量。

Curcumin inhibits hepatitis B virus infection by downregulating ccc DNA-bound histone acetylation

AIM To investigate the potential effect of curcumin on hepatitis B virus(HBV) covalently closed circular DNA(ccc DNA) and the underlying mechanism.METHODS A Hep G2.2.15 cell line stably transfected with HBV was treated with curcumin, and HBV surface antigen(HBs Ag) and e antigen(HBe Ag) expression levels were assessed by ELISA. Intracellular HBV DNA replication intermediates and ccc DNA were detected by Southern blot and real-time PCR, respectively. The acetylation levels of histones H3 and H4 were measured by Western blot. H3/H4-bound ccc DNA was detected by chromatin immunoprecipitation(Ch IP) assays. The deacetylase inhibitors trichostatin A and sodium butyrate were used to study the mechanism of action for curcumin. Additionally, short interfering RNAs(si RNAs) targeting HBV were tested along with curcumin.RESULTS Curcumin treatment led to time-and dose-dependent reductions in HBs Ag and HBe Ag expression and significant reductions in intracellular HBV DNA replication intermediates and HBV ccc DNA. After treatment with 20 μmol/L curcumin for 2 d, HBs Ag and ccc DNA levels in Hep G2.2.15 cells were reduced by up to 57.7%(P < 0.01) and 75.5%(P < 0.01), respectively, compared with levels in non-treated cells. Meanwhile, time-and dose-dependent reductions in the histone H3 acetylation levels were also detected upon treatment with curcumin, accompanied by reductions in H3-and H4-bound ccc DNA. Furthermore, the deacetylase inhibitors trichostatin A and sodium butyrate could block the effects of curcumin. Additionally, transfection of si RNAs targeting HBV enhanced the inhibitory effects of curcumin.CONCLUSION Curcumin inhibits HBV gene replication via downregulation of ccc DNA-bound histone acetylation and has the potential to be developed as a ccc DNA-targeting antiviral agent for hepatitis B.

Bridging peripheral nerves using a deacetyl chitin conduit combined with short-term electrical stimulation

Previous studies have demonstrated that deacetyl chitin conduit nerve bridging or electrical stimulation can effectively promote the regeneration of the injured peripheral nerve. We hypoth-esized that the combination of these two approaches could result in enhanced regeneration. Rats with right sciatic nerve injury were subjected to deacetyl chitin conduit bridging combined with electrical stimulation （0.1 ms, 3 V, 20 Hz, for 1 hour）. At 6 and 12 weeks after treatment, nerve conduction velocity, myelinated axon number, ifber diameter, axon diameter and the thickness of the myelin sheath in the stimulation group were better than in the non-stimulation group. The results indicate that deacetyl chitin conduit bridging combined with temporary electrical stimu-lation can promote peripheral nerve repair.

p-Toluenesulfonyl chloride as a new and effective catalyst for acetylation and formylation of hydroxyl compounds under mild conditions

The catalytic application of p-toluenesulfonyl chloride for efficient acetylation of various types of alcohols and phenols with acetic anhydride in solvent-free conditions is reported.Also structurally diverse alcohols were formylated using formic acid based on the use of catalytic amount of p-toluenesulfonyl chloride under solvent-free condition.The reactions were carried out in short reaction time and in good to excellent yields at room temperature.