Several studies have demonstrated that the Chinese herb Gastrodia elata Blume can protect against amyloid beta-peptide （Ap）-induced cell death. To investigate the possible therapeutic effects of Gastrodia elata Blum...Several studies have demonstrated that the Chinese herb Gastrodia elata Blume can protect against amyloid beta-peptide （Ap）-induced cell death. To investigate the possible therapeutic effects of Gastrodia elata Blume on Alzheimer＇s disease, we established a rat model of AIzheimer＇s disease by injecting A325-35 into bilateral hippocampi. These rats were intragastrically administered 500 or 1 000 mg/kg Gastrodia elata Blume per day for 52 consecutive days. Morris water maze tests showed that Gastrodia elata Blume treatment significantly improved the spatial memory of Alzheimer＇s disease rats. Congo red staining revealed that Gastrodia elata Blume significantly reduced the number of amyloid deposits in the hippocampus of these rats. Western blot analysis showed that choline acetyltransferase expression in the medial septum and hippocampus was significantly increased by the treatment of Gastrodia elata Blume, while EIIman method showed significant decrease in the activity of acetylcholinesterase in all three regions （prefrontal cortex, medial septum and hippocampus）. These findings suggest that long-term administration of Gastrodia elata Blume has therapeutic potential for Alzheimer＇s disease.展开更多
Our previous study revealed that early application of electrical field stimulation（EFS） with the anode at the lesion and the cathode distal to the lesion reduced injury potential, inhibited secondary injury and was ...Our previous study revealed that early application of electrical field stimulation（EFS） with the anode at the lesion and the cathode distal to the lesion reduced injury potential, inhibited secondary injury and was neuroprotective in the dorsal corticospinal tract after spinal cord injury（SCI）. The objective of this study was to further evaluate the effect of EFS on protection of anterior horn motoneurons and their target musculature after SCI and its mechanism. Rats were randomized into three equal groups. The EFS group received EFS for 30 minutes immediately after injury at T_（10）. SCI group rats were only subjected to SCI and sham group rats were only subjected to laminectomy. Luxol fast blue staining demonstrated that spinal cord tissue in the injury center was better protected; cross-sectional area and perimeter of injured tissue were significantly smaller in the EFS group than in the SCI group. Immunofluorescence and transmission electron microscopy showed that the number of spinal cord anterior horn motoneurons was greater and the number of abnormal neurons reduced in the EFS group compared with the SCI group. Wet weight and cross-sectional area of vastus lateralis muscles were smaller in the SCI group to in the sham group. However, EFS improved muscle atrophy and behavioral examination showed that EFS significantly increased the angle in the inclined plane test and Tarlov＇s motor grading score. The above results confirm that early EFS can effectively impede spinal cord anterior horn motoneuron loss, promote motor function recovery and reduce muscle atrophy in rats after SCI.展开更多
Glutathione is a key player in cellular redox homeostasis and, therefore, in the response to H2O2, but the factors regulating oxidation-activated glutathione synthesis are still unclear. We investigated H2O2-induced g...Glutathione is a key player in cellular redox homeostasis and, therefore, in the response to H2O2, but the factors regulating oxidation-activated glutathione synthesis are still unclear. We investigated H2O2-induced glutathione synthesis in a conditional Arabidopsis catalase-deficient mutant （cat2）. Plants were grown from seed at elevated CO2 for 5 weeks, then transferred to air in either short-day or long-day conditions. Compared to cat2 at elevated CO2 or wild-type plants in any condition, transfer of cat2 to air in both photoperiods caused measurable oxidation of the leaf glutathione pool within hours. Oxidation continued on subsequent days and was accompanied by accumulation of glutathione. This effect was stronger in cat2 transferred to air in short days, and was not linked to appreciable increases in the extractable activities of or transcripts encoding enzymes involved in the committed pathway of glutathione synthesis. In contrast, it was accompanied by increases in serine, O-acetylserine, and cysteine. These changes in metabolites were accompanied by induction of genes encoding adenosine phosphosulfate reductase （APR）, particularly APR3, as well as a specific serine acetyltransferase gene （SAT2.1） encoding a chloroplastic SAT. Marked induction of these genes was only observed in cat2 transferred to air in short-day conditions, where cysteine and glutathione accumulation was most dramatic. Unlike other SAT genes, which showed negligible induction in cat2, the relative abundance of APR and SAT2.1 transcripts was closely correlated with marker transcripts for H2O2 signaling. Together, the data underline the importance of cysteine synthesis in oxidant-induced up-regulation of glutathione synthesis and suggest that the chloroplast makes an important contribution to cysteine production under these circumstances.展开更多
The quantitative induction of VIN3 by low temperatures is required for PRC2 repression of FLC and promotion of flowering （vernalization） in Arabidopsis. Histone acetylation, a chromatin modification commonly associa...The quantitative induction of VIN3 by low temperatures is required for PRC2 repression of FLC and promotion of flowering （vernalization） in Arabidopsis. Histone acetylation, a chromatin modification commonly associated with gene transcription, increased on VIN3 chromatin in two spatially and temporally distinct phases in response to low temperatures. During short-term cold exposure, histone H3 acetylation at the transcription start site rapidly increased, implying that it is required for VlN3 induction. Subsequent changes in histone H3 and H4 acetylation occurred following continued VIN3 transcription during prolonged cold exposure. Members of the SAGA-like transcriptional adaptor complex, including the histone acetyltransferase GCNS, which induces expression of the cold acclimation pathway genes, do not regulate VlN3 induction during cold exposure, indicating that the cold acclimation pathway and the cold-induction of VlN3 are regulated by different transcriptional mechanisms. Mutations in the other 11 histone acetyltransferase genes did not affect VlN3 induction. However, nicotinamide, a histone deacetyiase inhibitor, induced VIN3 and altered histone acetylation at the VIN3 locus. VIN3 induction was proportional to the length of nicotinamide treatment, which was associated with an early-flowering phenotype and repression of FLC. However, unlike vernalization, the repression of FLC was independent of VIN3 activity. Nicotinamide treatment did not cause a change in the expression of any genes in the autonomous pathway or members of the PRC2 complex, the well characterized repressors of FLC. Our data suggest that FLC is repressed via a novel pathway involving the SIR2 class of histone deacetylases.展开更多
MicroRNAs （miRNA） that guide sequence-specific posttranscriptional gene silencing play an important role in gene expression required for both developmental processes and responses to environmental conditions in plan...MicroRNAs （miRNA） that guide sequence-specific posttranscriptional gene silencing play an important role in gene expression required for both developmental processes and responses to environmental conditions in plants. However, little is known about the transcriptional and posttranscriptional regulation of miRNA expression. Histone acetylation plays an important role in chromatin remodeling and is required for gene activation. By analyzing the accumulation of subset of miRNAs and the corresponding primary miRNAs in mutants of Arabidopsis, we show that histone acetyltransferase GCN5 （General control non-repressed protein 5） has a general repressive effect on miRNA production, while it is required for the expression of a subset of （e.g. stress-inducible） MIRNA genes. The general negative function of GCN5 in miRNA production is likely achieved through an indirect repression of the miRNA machinery genes such as DICER LIKE1 （DCL1）, SERRATE （SE）, HYPONASTIC LEAVES1 （HYL1） and ARGONAUTE1 （AGO1）. Chromatin immunoprecipitation assays revealed that GCN5 targets to a subset of MIRNA genes and is required for acetylation of histone H3 lysine 14 at these loci. Moreover, inhibition of histone deacetylation by trichostatin A treatment or in histone deacetylase gene mutants impaired the accumulation of certain miRNAs. These data together suggest that Arabidopsis GCN5 interferes with the miRNA pathway at both the transcriptional and posttranscriptional levels and histone acetylation/deacetylation is an epigenetic mechanism involved in the regulation of miRNA production.展开更多
Bone marrow mesenchymal stem cells were isolated, purified and cultured in vitro by Percoll density gradient centrifugation combined with the cell adherence method. Passages 3 5 bone marrow mesenchymal stem cells were...Bone marrow mesenchymal stem cells were isolated, purified and cultured in vitro by Percoll density gradient centrifugation combined with the cell adherence method. Passages 3 5 bone marrow mesenchymal stem cells were transplanted into rats with traumatic spinal cord injury via the caudal vein. Basso-Beattie-Bresnahan scores indicate that neurological function of experimental rats was significantly improved over transplantation time （1-5 weeks）. Expressions of choline acetyltransferase, glutamic acid decarboxytase and synapsins in the damaged spinal cord of rats was significantly increased after transplantation, determined by immunofluorescence staining and laser confocal scanning microscopy. Bone marrow mesenchymal stem cells that had migrated into the damaged area of rats in the experimental group began to express choline acetyltransferase, glutamic acid decarboxylase and synapsins, 3 weeks after transplantation. The Basso-Beattie- Bresnahan scores positively correlated with expression of choline acetyltransferase and synapsins. Experimental findings indicate that intravenously transplanted bone marrow mesenchymal stem cells traverse into the damaged spinal cord of rats, promote expression of choline acetyltransferase, glutamic acid decarboxylase and synapsins, and improve nerve function in rats with spinal cord injury.展开更多
Growth arrest-specific 5 (GAS5) is an anti-oncogene that has been extensively studied in tumors. However, research on GAS5 in the context of nervous system disease is rare at present. This study aimed to investigate t...Growth arrest-specific 5 (GAS5) is an anti-oncogene that has been extensively studied in tumors. However, research on GAS5 in the context of nervous system disease is rare at present. This study aimed to investigate the role of the long non-coding RNA GAS5 in rat pheochromocytoma cells (PC12 cells). GAS5-overexpressing lentivirus was transfected into PC12 cells, and expression levels of GAS5 and C-myc were detected by real-time PCR. Ratios of cells in S phase were detected by 5-ethynyl-2′-deoxyuridine. Immunohistochemical staining was used to detect the immunoreactivity of neuron microtubule markers Tuj1, doublecortin, and microtubule-associated protein 2. Apoptosis was detected by flow cytometry, while expression of acetylcholine in cells was detected by western blot assay. We found that GAS5 can promote PC12 cells to differentiate into Tuj1-positive neuron-like cells with longer processes. In addition, cell proliferation and cell cycle were significantly suppressed by GAS5, whereas it had no effect on apoptosis of PC12 cells. Our results indicate that GAS5 could increase the expression of choline acetyltransferase and acetylcholine release. Thus, we speculate that GAS5 is beneficial to the recovery of neurons and the cholinergic nervous system.展开更多
BACKGROUND Previous studies have shown that the Shi-pi-xiao-ji(SPXJ)herbal decoction formula is effective in suppressing hepatocellular carcinoma(HCC),but the underlying mechanisms are not known.Therefore,this study i...BACKGROUND Previous studies have shown that the Shi-pi-xiao-ji(SPXJ)herbal decoction formula is effective in suppressing hepatocellular carcinoma(HCC),but the underlying mechanisms are not known.Therefore,this study investigated whether the antitumor effects of the SPXJ formula in treating HCC were mediated by acetyl-coA acetyltransferase 1(ACAT1)-regulated cellular stiffness.Through a series of experiments,we concluded that SPXJ inhibits the progression of HCC by upregulating the expression level of ACAT1,lowering the level of cholesterol in the cell membrane,and altering the cellular stiffness,which provides a new idea for the research of traditional Chinese medicine against HCC.AIM To investigate the anti-tumor effects of the SPXJ formula on the malignant progression of HCC.METHODS HCC cells were cultured in vitro with SPXJ-containing serum prepared by injecting SPXJ formula into wild-type mice.The apoptotic rate and proliferative,invasive,and migratory abilities of control and SPXJ-treated HCC cells were compared.Atomic force microscopy was used to determine the cell surface morphology and the Young’s modulus values of the control and SPXJ-treated HCC cells.Plasma membrane cholesterol levels in HCC cells were detected using the Amplex Red cholesterol detection kit.ACAT1 protein levels were estimated using western blotting.RESULTS Compared with the vehicle group,SPXJ serum considerably reduced proliferation of HCC cells,increased stiffness and apoptosis of HCC cells,inhibited migration and invasion of HCC cells,decreased plasma membrane cholesterol levels,and upregulated ACAT1 protein levels.However,treatment of HCC cells with the water-soluble cholesterol promoted proliferation,migration,and invasion of HCC cells as well as decreased cell stiffness and plasma membrane cholesterol levels,but did not alter the apoptotic rate and ACAT1 protein expression levels compared with the vehicle control.CONCLUSION SPXJ formula inhibited proliferation,invasion,and migration of HCC cells by decreasing plasma membrane cho展开更多
MIcroglia/macrophage-mediated erythrophagocytosis plays a crucial role in hematoma clearance after intracerebral hemorrhage.Dynamic cytoskeletal changes accompany phagocytosis.However,whether and how these changes are...MIcroglia/macrophage-mediated erythrophagocytosis plays a crucial role in hematoma clearance after intracerebral hemorrhage.Dynamic cytoskeletal changes accompany phagocytosis.However,whether and how these changes are associated with microglia/macrophage-mediated erythrophagocytosis remain unclear.In this study,we investigated the function of acetylatedα-tubulin,a stabilized microtubule form,in microglia/macrophage erythrophagocytosis after intracerebral hemorrhage both in vitro and in vivo.We first assessed the function of acetylatedα-tubulin in erythrophagocytosis using primary DiO GFP-labeled red blood cells co-cultured with the BV2 microglia or RAW264.7 macrophage cell lines.Acetylatedα-tubulin expression was significantly decreased in BV2 and RAW264.7 cells during erythrophagocytosis.Moreover,silencingα-tubulin acetyltransferase 1(ATAT1),a newly discoveredα-tubulin acetyltransferase,decreased Ac-α-tub levels and enhanced the erythrophagocytosis by BV2 and RAW264.7 cells.Consistent with these findings,in ATAT1-/-mice,we observed increased ionized calcium binding adapter molecule 1(Iba1)and Perls-positive microglia/macrophage phagocytes of red blood cells in peri-hematoma and reduced hematoma volume in mice with intracerebral hemorrhage.Additionally,knocking out ATAT1 alleviated neuronal apoptosis and pro-inflammatory cytokines and increased anti-inflammatory cytokines around the hematoma,ultimately improving neurological recovery of mice after intracerebral hemorrhage.These findings suggest that ATAT1 deficiency accelerates erythrophagocytosis by microglia/macrophages and hematoma absorption after intracerebral hemorrhage.These results provide novel insights into the mechanisms of hematoma clearance and suggest ATAT1 as a potential target for the treatment of intracerebral hemorrhage.展开更多
To investigate the protective effect of dl 3 n butylphthalide (NBP) as an anti cerebral ischemic drug on brain damage 24?h after closed head injury in mice Methods Closed head injury was induced by dropping a 50...To investigate the protective effect of dl 3 n butylphthalide (NBP) as an anti cerebral ischemic drug on brain damage 24?h after closed head injury in mice Methods Closed head injury was induced by dropping a 50 g weight from a height of 18?cm on a metal impounder resting on the parietal bone in mice Results The neurotraumatic model induced impair^ment of memory function, significant cerebral edema, and disruption of the blood brain barrier dl 3 n butylphthalide (50?mg·kg 1 ) given intraperitoneally 5 minutes and 60 minutes after the onset of closed head injury was found to attenuate the impairment of memory function ( P <0 05), alleviate brain edema in the injured cerebral cortex ( P <0 05), and reduce extravasation of plasma protein bound to Evans blue dye by 63 5% ( P <0 01) NBP was also shown to increase the activity of choline acetyltransferase in the injured cortex to 0 83±0 21?ng·min 1 ·mg 1 ( P <0 01, compared with 0 48±0 14?ng·min 1 ·mg 1 of vehicle group) Conclusion NBP provides therapeutic response in experimental closed head injury展开更多
BACKGROUND： The main components of the traditional Chinese medicine compound Nao Yikang have been shown to possibly alleviate neural damage. OBJECTIVE： To observe the effects of Nao Yikang on expression of choline a...BACKGROUND： The main components of the traditional Chinese medicine compound Nao Yikang have been shown to possibly alleviate neural damage. OBJECTIVE： To observe the effects of Nao Yikang on expression of choline acetyltransferase （CHAT） and caspase-3 in the rat brains of an experimental Alzheimer＇s disease （AD） model, and to investigate the mechanisms of potential neuroprotective effects. DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed at the Department of Pathophysiology, Medical School of Nantong University between November 2006 and December 2007. MATERIALS： The main active components of Nao Yikang were as follows： prepared polygonum multiflorum, Rhizoma anemarrhenae, and Rhizoma acori tatarinowii. Nao Yikang granules were prepared by Nantong Hospital of Traditional Chinese Medicine. Ibotenic acid （IBO） was purchased from Sigma-Aldrich, USA, ChAT goat anti-rat antibody from Chemicon, USA, and cleaved caspase-3 rabbit anti-rat （Asp175） （5A1） antibody from Cell Signaling, USA. METHODS： A total of 60 male, Sprague Dawley rats （2 months old） were randomly assigned to 6 groups： sham-surgery, model, Nao Yikang 1.73, 3.45, 6.90 g/kg per day, and piracetam, with 10 rats in each group. Bilateral infusions of 5 pg IBO into the nucleus basalis of Meynert were performed with Hamilton syringe and stereotaxic apparatus for AD model establishment. For the sham-surgery group, rats received 1 μL saline in the identical stereotaxic position. From the second day, Nao Yikang groups were administrated 1.73, 3.45, and 6.90 g/kg per day Nao Yikang, respectively, while the piracetam group received 0.04 g/mL piracetam, the model group received 0.5% sodium carboxymethyl cellulose, and the sham-surgery group received normal saline. Rats were intragastrically administered 1 mL/100 g daily for 28 consecutive days. MAIN OUTCOME MEASURES： Following treatment of the various solutions for 28 days, Western blot was utilized to observe ChAT expression in the frontal cortex 展开更多
Objective To investigate the H_ 2O_ 2-induced expression of human histone acetyltransferase-like protein (hALP), a telomerase regulation-associated gene, and its effects on the stress-triggered cellular senescence.Met...Objective To investigate the H_ 2O_ 2-induced expression of human histone acetyltransferase-like protein (hALP), a telomerase regulation-associated gene, and its effects on the stress-triggered cellular senescence.Methods The induced expression of hALP was measured by semi-quantitative RT-PCR and immunofluorescent histochemistry after treatment of HeLa cells by H_ 2O_ 2.The effects of hALP expression on cellular responses to H_ 2O_ 2 were analyzed by MTT, flowcytometry, and SA-β-gal staining, respectively.Results hALP mRNA could be dose-dependently induced by treatments of 0.2-1.6 mmol/L H_ 2O_ 2, and the induction could be observed after 6 hours and kept for 36 hours in the presence of 0.4 mmol/L H_ 2O_ 2.Meanwhile, the immunofluorescent staining showed marked stronger nuclear intensity of hALP protein in H_ 2O_ 2-treated HeLa cells.In the treatment of H_ 2O_ 2, the ectopic expression of hALP enhanced continuous growth and overcame G_ 2/M arrest as well as decreased senescence-associated β-gal staining.On the contrary, the transfected clones with antisense or blank vector and original HeLa cells presented growth suppression, G_ 2/M delay and higher percentage of SA-β-gal activities in the presence of H_ 2 O_ 2.Conclusions The expression of hALP could be up-regulated by treatment of H_ 2O_ 2, and elevated expression could enhance cellular resistance to H_ 2O_ 2-induced cellular senescence.The data might be of references to elucidation of basic biological function of hALP gene and its associated telomerase activity.展开更多
Plant pathogenic bacteria deliver effectors into plant cells to suppress immunity and promote pathogen survival;however, these effectors can be recognised by plant disease resistance (R) proteins to activate innate im...Plant pathogenic bacteria deliver effectors into plant cells to suppress immunity and promote pathogen survival;however, these effectors can be recognised by plant disease resistance (R) proteins to activate innate immunity. The bacterial acetyltransferase effectors HopZ5 and AvrBsT trigger immunity in Arabidopsis thaliana genotypes lacking SUPPRESSOR OF AVRBST-ELICITED RESISTANCE 1 (SOBER1). Using an Arabidopsis accession, Tscha-1, that naturally lacks functional SOBER1 but is unable to recognise HopZ5, we demonstrate that RESISTANCE TO P. SYRINGAE PV MACULICOLA 1 (RPM1) and RPM1-INTERACTING PROTEIN 4 (RIN4) are indispensable for HopZ5- or AvrBsT-triggered immunity. Remarkably, T166 of RIN4, the phosphorylation of which is induced by AvrB and AvrRpm1, was directly acetylated by HopZ5 and AvrBsT. Furthermore, we demonstrate that the acetylation of RIN4 T166 is required and sufficient for HopZ5- or AvrBsT-triggered RPM1-dependent defence activation. Finally, we show that SOBER1 interferes with HopZ5- or AvrBsT-triggered immunity by deacetylating RIN4 T166. We have thus elucidated detailed molecular mechanisms underlying the activation and suppression of plant innate immunity triggered by two bacterial acetyltransferases, HopZ5 and AvrBsT from different bacterial pathogens.展开更多
基金funded by Muju Tianma Native Local Industrial Center,Korea
文摘Several studies have demonstrated that the Chinese herb Gastrodia elata Blume can protect against amyloid beta-peptide （Ap）-induced cell death. To investigate the possible therapeutic effects of Gastrodia elata Blume on Alzheimer＇s disease, we established a rat model of AIzheimer＇s disease by injecting A325-35 into bilateral hippocampi. These rats were intragastrically administered 500 or 1 000 mg/kg Gastrodia elata Blume per day for 52 consecutive days. Morris water maze tests showed that Gastrodia elata Blume treatment significantly improved the spatial memory of Alzheimer＇s disease rats. Congo red staining revealed that Gastrodia elata Blume significantly reduced the number of amyloid deposits in the hippocampus of these rats. Western blot analysis showed that choline acetyltransferase expression in the medial septum and hippocampus was significantly increased by the treatment of Gastrodia elata Blume, while EIIman method showed significant decrease in the activity of acetylcholinesterase in all three regions （prefrontal cortex, medial septum and hippocampus）. These findings suggest that long-term administration of Gastrodia elata Blume has therapeutic potential for Alzheimer＇s disease.
基金supported by the National Natural Science Foundation of China,No.31400717,51577183the Natural Science Foundation of Beijing of China,No.7164317the Youth Innovation Promotion Association CAS,No.2018172
文摘Our previous study revealed that early application of electrical field stimulation（EFS） with the anode at the lesion and the cathode distal to the lesion reduced injury potential, inhibited secondary injury and was neuroprotective in the dorsal corticospinal tract after spinal cord injury（SCI）. The objective of this study was to further evaluate the effect of EFS on protection of anterior horn motoneurons and their target musculature after SCI and its mechanism. Rats were randomized into three equal groups. The EFS group received EFS for 30 minutes immediately after injury at T_（10）. SCI group rats were only subjected to SCI and sham group rats were only subjected to laminectomy. Luxol fast blue staining demonstrated that spinal cord tissue in the injury center was better protected; cross-sectional area and perimeter of injured tissue were significantly smaller in the EFS group than in the SCI group. Immunofluorescence and transmission electron microscopy showed that the number of spinal cord anterior horn motoneurons was greater and the number of abnormal neurons reduced in the EFS group compared with the SCI group. Wet weight and cross-sectional area of vastus lateralis muscles were smaller in the SCI group to in the sham group. However, EFS improved muscle atrophy and behavioral examination showed that EFS significantly increased the angle in the inclined plane test and Tarlov＇s motor grading score. The above results confirm that early EFS can effectively impede spinal cord anterior horn motoneuron loss, promote motor function recovery and reduce muscle atrophy in rats after SCI.
文摘Glutathione is a key player in cellular redox homeostasis and, therefore, in the response to H2O2, but the factors regulating oxidation-activated glutathione synthesis are still unclear. We investigated H2O2-induced glutathione synthesis in a conditional Arabidopsis catalase-deficient mutant （cat2）. Plants were grown from seed at elevated CO2 for 5 weeks, then transferred to air in either short-day or long-day conditions. Compared to cat2 at elevated CO2 or wild-type plants in any condition, transfer of cat2 to air in both photoperiods caused measurable oxidation of the leaf glutathione pool within hours. Oxidation continued on subsequent days and was accompanied by accumulation of glutathione. This effect was stronger in cat2 transferred to air in short days, and was not linked to appreciable increases in the extractable activities of or transcripts encoding enzymes involved in the committed pathway of glutathione synthesis. In contrast, it was accompanied by increases in serine, O-acetylserine, and cysteine. These changes in metabolites were accompanied by induction of genes encoding adenosine phosphosulfate reductase （APR）, particularly APR3, as well as a specific serine acetyltransferase gene （SAT2.1） encoding a chloroplastic SAT. Marked induction of these genes was only observed in cat2 transferred to air in short-day conditions, where cysteine and glutathione accumulation was most dramatic. Unlike other SAT genes, which showed negligible induction in cat2, the relative abundance of APR and SAT2.1 transcripts was closely correlated with marker transcripts for H2O2 signaling. Together, the data underline the importance of cysteine synthesis in oxidant-induced up-regulation of glutathione synthesis and suggest that the chloroplast makes an important contribution to cysteine production under these circumstances.
文摘The quantitative induction of VIN3 by low temperatures is required for PRC2 repression of FLC and promotion of flowering （vernalization） in Arabidopsis. Histone acetylation, a chromatin modification commonly associated with gene transcription, increased on VIN3 chromatin in two spatially and temporally distinct phases in response to low temperatures. During short-term cold exposure, histone H3 acetylation at the transcription start site rapidly increased, implying that it is required for VlN3 induction. Subsequent changes in histone H3 and H4 acetylation occurred following continued VIN3 transcription during prolonged cold exposure. Members of the SAGA-like transcriptional adaptor complex, including the histone acetyltransferase GCNS, which induces expression of the cold acclimation pathway genes, do not regulate VlN3 induction during cold exposure, indicating that the cold acclimation pathway and the cold-induction of VlN3 are regulated by different transcriptional mechanisms. Mutations in the other 11 histone acetyltransferase genes did not affect VlN3 induction. However, nicotinamide, a histone deacetyiase inhibitor, induced VIN3 and altered histone acetylation at the VIN3 locus. VIN3 induction was proportional to the length of nicotinamide treatment, which was associated with an early-flowering phenotype and repression of FLC. However, unlike vernalization, the repression of FLC was independent of VIN3 activity. Nicotinamide treatment did not cause a change in the expression of any genes in the autonomous pathway or members of the PRC2 complex, the well characterized repressors of FLC. Our data suggest that FLC is repressed via a novel pathway involving the SIR2 class of histone deacetylases.
文摘MicroRNAs （miRNA） that guide sequence-specific posttranscriptional gene silencing play an important role in gene expression required for both developmental processes and responses to environmental conditions in plants. However, little is known about the transcriptional and posttranscriptional regulation of miRNA expression. Histone acetylation plays an important role in chromatin remodeling and is required for gene activation. By analyzing the accumulation of subset of miRNAs and the corresponding primary miRNAs in mutants of Arabidopsis, we show that histone acetyltransferase GCN5 （General control non-repressed protein 5） has a general repressive effect on miRNA production, while it is required for the expression of a subset of （e.g. stress-inducible） MIRNA genes. The general negative function of GCN5 in miRNA production is likely achieved through an indirect repression of the miRNA machinery genes such as DICER LIKE1 （DCL1）, SERRATE （SE）, HYPONASTIC LEAVES1 （HYL1） and ARGONAUTE1 （AGO1）. Chromatin immunoprecipitation assays revealed that GCN5 targets to a subset of MIRNA genes and is required for acetylation of histone H3 lysine 14 at these loci. Moreover, inhibition of histone deacetylation by trichostatin A treatment or in histone deacetylase gene mutants impaired the accumulation of certain miRNAs. These data together suggest that Arabidopsis GCN5 interferes with the miRNA pathway at both the transcriptional and posttranscriptional levels and histone acetylation/deacetylation is an epigenetic mechanism involved in the regulation of miRNA production.
基金supported by the Doctoral Fund of Ministry of Education of China,No.20060392003Academic Development Foundation of Fujian Medical University, No.JS08004
文摘Bone marrow mesenchymal stem cells were isolated, purified and cultured in vitro by Percoll density gradient centrifugation combined with the cell adherence method. Passages 3 5 bone marrow mesenchymal stem cells were transplanted into rats with traumatic spinal cord injury via the caudal vein. Basso-Beattie-Bresnahan scores indicate that neurological function of experimental rats was significantly improved over transplantation time （1-5 weeks）. Expressions of choline acetyltransferase, glutamic acid decarboxytase and synapsins in the damaged spinal cord of rats was significantly increased after transplantation, determined by immunofluorescence staining and laser confocal scanning microscopy. Bone marrow mesenchymal stem cells that had migrated into the damaged area of rats in the experimental group began to express choline acetyltransferase, glutamic acid decarboxylase and synapsins, 3 weeks after transplantation. The Basso-Beattie- Bresnahan scores positively correlated with expression of choline acetyltransferase and synapsins. Experimental findings indicate that intravenously transplanted bone marrow mesenchymal stem cells traverse into the damaged spinal cord of rats, promote expression of choline acetyltransferase, glutamic acid decarboxylase and synapsins, and improve nerve function in rats with spinal cord injury.
基金supported by the National Natural Science Foundation of China,No.81501133(to HML)Postgraduate Research&Practice Innovation Program of Jiangsu Province of China,No.KYCX17-1931(to HYZ)+3 种基金Undergraduate Innovation and Entrepreneurship Training Project of Nantong University of China,No.2018150(to STZ)Pre-research Project of Natural Science Foundation of Nantong University of China,No.17ZY19(to HH)Scientific Research Fund Project of Nantong University Xinglin College of China,No.2018K131(to HYZ)Nantong Science and Technology Project of China,No.JC2018064(to HYZ)
文摘Growth arrest-specific 5 (GAS5) is an anti-oncogene that has been extensively studied in tumors. However, research on GAS5 in the context of nervous system disease is rare at present. This study aimed to investigate the role of the long non-coding RNA GAS5 in rat pheochromocytoma cells (PC12 cells). GAS5-overexpressing lentivirus was transfected into PC12 cells, and expression levels of GAS5 and C-myc were detected by real-time PCR. Ratios of cells in S phase were detected by 5-ethynyl-2′-deoxyuridine. Immunohistochemical staining was used to detect the immunoreactivity of neuron microtubule markers Tuj1, doublecortin, and microtubule-associated protein 2. Apoptosis was detected by flow cytometry, while expression of acetylcholine in cells was detected by western blot assay. We found that GAS5 can promote PC12 cells to differentiate into Tuj1-positive neuron-like cells with longer processes. In addition, cell proliferation and cell cycle were significantly suppressed by GAS5, whereas it had no effect on apoptosis of PC12 cells. Our results indicate that GAS5 could increase the expression of choline acetyltransferase and acetylcholine release. Thus, we speculate that GAS5 is beneficial to the recovery of neurons and the cholinergic nervous system.
基金Supported by the National Natural Science Foundation of China,No.82074425Hunan Science and Technology Planning Project,No.2016SK2051 and No.2023SK2057the Hunan Provincial Administration of Traditional Chinese Medicine Research Project,No.B2023089.
文摘BACKGROUND Previous studies have shown that the Shi-pi-xiao-ji(SPXJ)herbal decoction formula is effective in suppressing hepatocellular carcinoma(HCC),but the underlying mechanisms are not known.Therefore,this study investigated whether the antitumor effects of the SPXJ formula in treating HCC were mediated by acetyl-coA acetyltransferase 1(ACAT1)-regulated cellular stiffness.Through a series of experiments,we concluded that SPXJ inhibits the progression of HCC by upregulating the expression level of ACAT1,lowering the level of cholesterol in the cell membrane,and altering the cellular stiffness,which provides a new idea for the research of traditional Chinese medicine against HCC.AIM To investigate the anti-tumor effects of the SPXJ formula on the malignant progression of HCC.METHODS HCC cells were cultured in vitro with SPXJ-containing serum prepared by injecting SPXJ formula into wild-type mice.The apoptotic rate and proliferative,invasive,and migratory abilities of control and SPXJ-treated HCC cells were compared.Atomic force microscopy was used to determine the cell surface morphology and the Young’s modulus values of the control and SPXJ-treated HCC cells.Plasma membrane cholesterol levels in HCC cells were detected using the Amplex Red cholesterol detection kit.ACAT1 protein levels were estimated using western blotting.RESULTS Compared with the vehicle group,SPXJ serum considerably reduced proliferation of HCC cells,increased stiffness and apoptosis of HCC cells,inhibited migration and invasion of HCC cells,decreased plasma membrane cholesterol levels,and upregulated ACAT1 protein levels.However,treatment of HCC cells with the water-soluble cholesterol promoted proliferation,migration,and invasion of HCC cells as well as decreased cell stiffness and plasma membrane cholesterol levels,but did not alter the apoptotic rate and ACAT1 protein expression levels compared with the vehicle control.CONCLUSION SPXJ formula inhibited proliferation,invasion,and migration of HCC cells by decreasing plasma membrane cho
基金supported by Science and Technology Innovation Enhancement Project of Army Medical University(to LX).
文摘MIcroglia/macrophage-mediated erythrophagocytosis plays a crucial role in hematoma clearance after intracerebral hemorrhage.Dynamic cytoskeletal changes accompany phagocytosis.However,whether and how these changes are associated with microglia/macrophage-mediated erythrophagocytosis remain unclear.In this study,we investigated the function of acetylatedα-tubulin,a stabilized microtubule form,in microglia/macrophage erythrophagocytosis after intracerebral hemorrhage both in vitro and in vivo.We first assessed the function of acetylatedα-tubulin in erythrophagocytosis using primary DiO GFP-labeled red blood cells co-cultured with the BV2 microglia or RAW264.7 macrophage cell lines.Acetylatedα-tubulin expression was significantly decreased in BV2 and RAW264.7 cells during erythrophagocytosis.Moreover,silencingα-tubulin acetyltransferase 1(ATAT1),a newly discoveredα-tubulin acetyltransferase,decreased Ac-α-tub levels and enhanced the erythrophagocytosis by BV2 and RAW264.7 cells.Consistent with these findings,in ATAT1-/-mice,we observed increased ionized calcium binding adapter molecule 1(Iba1)and Perls-positive microglia/macrophage phagocytes of red blood cells in peri-hematoma and reduced hematoma volume in mice with intracerebral hemorrhage.Additionally,knocking out ATAT1 alleviated neuronal apoptosis and pro-inflammatory cytokines and increased anti-inflammatory cytokines around the hematoma,ultimately improving neurological recovery of mice after intracerebral hemorrhage.These findings suggest that ATAT1 deficiency accelerates erythrophagocytosis by microglia/macrophages and hematoma absorption after intracerebral hemorrhage.These results provide novel insights into the mechanisms of hematoma clearance and suggest ATAT1 as a potential target for the treatment of intracerebral hemorrhage.
基金TheworkwassupportedbythegrantofStateScienceandTechnologyCommissionofChina (No .94 ZD 0 1 )
文摘To investigate the protective effect of dl 3 n butylphthalide (NBP) as an anti cerebral ischemic drug on brain damage 24?h after closed head injury in mice Methods Closed head injury was induced by dropping a 50 g weight from a height of 18?cm on a metal impounder resting on the parietal bone in mice Results The neurotraumatic model induced impair^ment of memory function, significant cerebral edema, and disruption of the blood brain barrier dl 3 n butylphthalide (50?mg·kg 1 ) given intraperitoneally 5 minutes and 60 minutes after the onset of closed head injury was found to attenuate the impairment of memory function ( P <0 05), alleviate brain edema in the injured cerebral cortex ( P <0 05), and reduce extravasation of plasma protein bound to Evans blue dye by 63 5% ( P <0 01) NBP was also shown to increase the activity of choline acetyltransferase in the injured cortex to 0 83±0 21?ng·min 1 ·mg 1 ( P <0 01, compared with 0 48±0 14?ng·min 1 ·mg 1 of vehicle group) Conclusion NBP provides therapeutic response in experimental closed head injury
基金Supported by: the Natural Science Foundation of Jiangsu Province, No. BK2004048Social Development and Technology Plan of Nantong City, No. K2008009
文摘BACKGROUND： The main components of the traditional Chinese medicine compound Nao Yikang have been shown to possibly alleviate neural damage. OBJECTIVE： To observe the effects of Nao Yikang on expression of choline acetyltransferase （CHAT） and caspase-3 in the rat brains of an experimental Alzheimer＇s disease （AD） model, and to investigate the mechanisms of potential neuroprotective effects. DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed at the Department of Pathophysiology, Medical School of Nantong University between November 2006 and December 2007. MATERIALS： The main active components of Nao Yikang were as follows： prepared polygonum multiflorum, Rhizoma anemarrhenae, and Rhizoma acori tatarinowii. Nao Yikang granules were prepared by Nantong Hospital of Traditional Chinese Medicine. Ibotenic acid （IBO） was purchased from Sigma-Aldrich, USA, ChAT goat anti-rat antibody from Chemicon, USA, and cleaved caspase-3 rabbit anti-rat （Asp175） （5A1） antibody from Cell Signaling, USA. METHODS： A total of 60 male, Sprague Dawley rats （2 months old） were randomly assigned to 6 groups： sham-surgery, model, Nao Yikang 1.73, 3.45, 6.90 g/kg per day, and piracetam, with 10 rats in each group. Bilateral infusions of 5 pg IBO into the nucleus basalis of Meynert were performed with Hamilton syringe and stereotaxic apparatus for AD model establishment. For the sham-surgery group, rats received 1 μL saline in the identical stereotaxic position. From the second day, Nao Yikang groups were administrated 1.73, 3.45, and 6.90 g/kg per day Nao Yikang, respectively, while the piracetam group received 0.04 g/mL piracetam, the model group received 0.5% sodium carboxymethyl cellulose, and the sham-surgery group received normal saline. Rats were intragastrically administered 1 mL/100 g daily for 28 consecutive days. MAIN OUTCOME MEASURES： Following treatment of the various solutions for 28 days, Western blot was utilized to observe ChAT expression in the frontal cortex
文摘Objective To investigate the H_ 2O_ 2-induced expression of human histone acetyltransferase-like protein (hALP), a telomerase regulation-associated gene, and its effects on the stress-triggered cellular senescence.Methods The induced expression of hALP was measured by semi-quantitative RT-PCR and immunofluorescent histochemistry after treatment of HeLa cells by H_ 2O_ 2.The effects of hALP expression on cellular responses to H_ 2O_ 2 were analyzed by MTT, flowcytometry, and SA-β-gal staining, respectively.Results hALP mRNA could be dose-dependently induced by treatments of 0.2-1.6 mmol/L H_ 2O_ 2, and the induction could be observed after 6 hours and kept for 36 hours in the presence of 0.4 mmol/L H_ 2O_ 2.Meanwhile, the immunofluorescent staining showed marked stronger nuclear intensity of hALP protein in H_ 2O_ 2-treated HeLa cells.In the treatment of H_ 2O_ 2, the ectopic expression of hALP enhanced continuous growth and overcame G_ 2/M arrest as well as decreased senescence-associated β-gal staining.On the contrary, the transfected clones with antisense or blank vector and original HeLa cells presented growth suppression, G_ 2/M delay and higher percentage of SA-β-gal activities in the presence of H_ 2 O_ 2.Conclusions The expression of hALP could be up-regulated by treatment of H_ 2O_ 2, and elevated expression could enhance cellular resistance to H_ 2O_ 2-induced cellular senescence.The data might be of references to elucidation of basic biological function of hALP gene and its associated telomerase activity.
基金This research was supported by Basic Science Research Programs through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2019R1I1A1A01060108)Korean government(MSIT)(NRF-2018R1A5A1023599 and NRF-2019R1A2C2084705)。
文摘Plant pathogenic bacteria deliver effectors into plant cells to suppress immunity and promote pathogen survival;however, these effectors can be recognised by plant disease resistance (R) proteins to activate innate immunity. The bacterial acetyltransferase effectors HopZ5 and AvrBsT trigger immunity in Arabidopsis thaliana genotypes lacking SUPPRESSOR OF AVRBST-ELICITED RESISTANCE 1 (SOBER1). Using an Arabidopsis accession, Tscha-1, that naturally lacks functional SOBER1 but is unable to recognise HopZ5, we demonstrate that RESISTANCE TO P. SYRINGAE PV MACULICOLA 1 (RPM1) and RPM1-INTERACTING PROTEIN 4 (RIN4) are indispensable for HopZ5- or AvrBsT-triggered immunity. Remarkably, T166 of RIN4, the phosphorylation of which is induced by AvrB and AvrRpm1, was directly acetylated by HopZ5 and AvrBsT. Furthermore, we demonstrate that the acetylation of RIN4 T166 is required and sufficient for HopZ5- or AvrBsT-triggered RPM1-dependent defence activation. Finally, we show that SOBER1 interferes with HopZ5- or AvrBsT-triggered immunity by deacetylating RIN4 T166. We have thus elucidated detailed molecular mechanisms underlying the activation and suppression of plant innate immunity triggered by two bacterial acetyltransferases, HopZ5 and AvrBsT from different bacterial pathogens.
