AIM:To evaluate the effects of LIN28A(human)on high glucose-induced retinal pigmented epithelium(RPE)cell injury and its possible mechanism.METHODS:Diabetic retinopathy model was generated following 48h of exposure to...AIM:To evaluate the effects of LIN28A(human)on high glucose-induced retinal pigmented epithelium(RPE)cell injury and its possible mechanism.METHODS:Diabetic retinopathy model was generated following 48h of exposure to 30 mmol/L high glucose(HG)in ARPE-19 cells.Quantitative real-time polymerase chain reaction(qRT-PCR)and Western blot tested the expression of the corresponding genes and proteins.Cell viability as well as apoptosis was determined through cell counting kit-8(CCK-8)and flow cytometry assays.Immunofluorescence assay was adopted to evaluate autophagy activity.Caspase 3 activity,oxidative stress markers,and cytokines were appraised adopting their commercial kits,respectively.Finally,ARPE-19 cells were preincubated with EX527,a Sirtuin 1(SIRT1)inhibitor,prior to HG stimulation to validate the regulatory mechanism.RESULTS:LIN28A was downregulated in HG-challenged ARPE-19 cells.LIN28A overexpression greatly inhibited HGinduced ARPE-19 cell viability loss,apoptosis,oxidative damage as well as inflammatory response.Meanwhile,the repressed autophagy and SIRT1 in ARPE-19 cells challenged with HG were elevated after LIN28A overexpression.In addition,treatment of EX527 greatly inhibited the activated autophagy following LIN28A overexpression and partly abolished the protective role of LIN28A against HG-elicited apoptosis,oxidative damage as well as inflammation in ARPE-19 cells.CONCLUSION:LIN28A exerts a protective role against HG-elicited RPE oxidative damage,inflammation,as well as apoptosis via regulating SIRT1/autophagy.展开更多
Objective:To explore the regulatory mechanism of transient receptor potential melastatin-7(TRPM7)in high glucose-induced renal tubular epithelial cell injury.Methods:The expression of TRPM7 in the serum of diabetic ne...Objective:To explore the regulatory mechanism of transient receptor potential melastatin-7(TRPM7)in high glucose-induced renal tubular epithelial cell injury.Methods:The expression of TRPM7 in the serum of diabetic nephropathy patients and high glucose-induced HK-2 cells was detected by RT-qPCR.Then,the TRPM7 interference vector was constructed,and the downstream high mobility group box 1(HMGB1)/Toll-like receptor 4(TLR4)signaling pathway proteins were detected.Next,in addition to interference with TRPM7 expression,overexpression of HMGB1 in high glucose-induced HK-2 cells was performed.Cell activity,apoptosis,oxidative stress levels,and inflammation levels were determined by CCK8,TUNEL,Western blotting,immunofluorescence and related kits.Results:TRPM7 expression was upregulated in the serum of diabetic nephropathy patients and high glucose-induced HK-2 cells.Interference with TRPM7 reduced cell damage,epithelial-mesenchymal transition,oxidative stress,and inflammatory response in high glucose-induced HK-2 cells via inhibiting the HMGB1/TLR4 signaling pathway.However,the effects induced by TRPM7 silencing were abrogated by HMGB1 overexpression.Conclusions:Decreased TRPM7 alleviates high glucose-induced renal tubular epithelial cell injury by inhibiting the HMGB1/TLR4 signaling pathway.Further animal experiments and clinical trials are warranted to verify its effect.展开更多
MicroRNAs(miRNAs) are endogenous 20 -23 -nucleotide (nt) -containing small non-coding RNAs that negatively regulate gene expression in diverse biological and pathological processes,including cell differentiation,proli...MicroRNAs(miRNAs) are endogenous 20 -23 -nucleotide (nt) -containing small non-coding RNAs that negatively regulate gene expression in diverse biological and pathological processes,including cell differentiation,proliferation, apoptosis,heart disease and human cancers.We investigated miR-133 expression and its potential role in a high glucose-induced myocardium in Streptozotocin(STZ)-induced C57bl6 mouse model of diabetes.miR-133 expression was significantly increased in myocardium in a time-dependent manner after STZ treatment.IGF1 receptor(IGF1R) protein was dramatically decreased without obvious up-regulation of its mRNA level post hyperglycemia.IGF1R protein level was decreaed with increase of its transcript level in neonatal mouse ventricular cardiomyocytes induced by high D-glucose concentration. Dual luciferase assay revealed that miR133 could interact with specific sites in the 3’UTR of IGF1R gene.p-ERK and p-Akt levels were reduced in neonatal mouse cardiomyocytes over-expressed with miR133 after IGF treatment.Introduction of functional miR-133,IGF1R siRNA into neonatal mouse cardiomyocytes could enhance cardiomyocyte apoptosis.These results implicate that miR-133 is involved in contributing to high glucose-induced cardiomyocyte apoptosis via regulating IGF1R expression post-transcriptionally.展开更多
Hyperglycemia is an important initiator of cardiovascular disease, contributing to the de- velopment of cardiomyocyte death and diabetic complications. The purpose of the present study was to investigate whether high ...Hyperglycemia is an important initiator of cardiovascular disease, contributing to the de- velopment of cardiomyocyte death and diabetic complications. The purpose of the present study was to investigate whether high glucose state could induce apoptosis of rat cardiomyocyte cell line H9c2 through microRNA-mediated Bcl-2 signaling pathway. The expression of miR-34a and Bcl-2 mRNA was detected by using real-time PCR. Western blotting was used to examine the changes in apop- tosis-associated protein Bcl-2. Apoptosis of H9c2 cells was tested by using flow cytometry. The results showed that the expression of miR-34a was significantly elevated and that of Bcl-2 was strongly re- duced, and apoptosis of cardiomyocytes was apparently increased in the high-glucose-treated H9c2 cells as compared with normal-glucose-treated controls. In addition, we identified Bcl-2 gene was the target of miR-34a, miR-34a mimics reduced the expression of Bcl-2 and increased glucose-induced apoptosis, but miR-34a inhibitor acted as the opposite mediator. Our data demonstrate that miR-34a contributes to high glucose-induced decreases in Bcl-2 expression and subsequent cardiomyocyte apoptosis.展开更多
Quercetin can reverse high glucose-induced inhibition of neural cell proliferation, and therefore may have a neuroprotective effect in diabetic peripheral neuropathy. It is difficult to obtain pri- mary Schwann cells ...Quercetin can reverse high glucose-induced inhibition of neural cell proliferation, and therefore may have a neuroprotective effect in diabetic peripheral neuropathy. It is difficult to obtain pri- mary Schwann cells and RSC96 cells could replace primary Schwann cells in studies of the role of autophagy in the mechanism underlying diabetic peripheral neuropathy. Here, we show that under high glucose conditions, there are fewer autophagosomes in immortalized rat RSC96 cells and primary rat Schwann ceils than under control conditions, the proliferative activity of both cell types is significantly impaired, and the expression of Berlin- 1 and LC3, the molecular mark- ers for autophagy, is significantly lower. After intervention with quercetin, the autophagic and proliferative activity of both cell types is rescued. These results suggest that quercetin can allevi- ate high glucose-induced damage to Schwann cells by autophagy.展开更多
Objective To explore the protective effects of dexmedetomidine(Dex)against high glucose-induced epithelial-mesenchymal transition in HK-2 cells and relevant mechanisms.Methods HK-2 cells were exposed to either glucose...Objective To explore the protective effects of dexmedetomidine(Dex)against high glucose-induced epithelial-mesenchymal transition in HK-2 cells and relevant mechanisms.Methods HK-2 cells were exposed to either glucose or glucose+Dex for 6 h.The production of ROS,morphology of HK-2 cells,and cell cycle were detected.Moreover,the expression of AKT,p-AKT,ERK,pERK,PI3 K,E-Cadherin,Claudin-1,andα-SMA were determined and compared between HK-2 cells exposed to glucose and those exposed to both glucose and Dex with or without PI3 K/AKT pathway inhibitor LY294002 and ERK pathway inhibitor U0126.Results Compared with HK-2 cells exposed to high level of glucose,the HK-2 cells exposed to both high level of glucose and Dex showed:(1)lower level of ROS production;(2)cell morphology was complete;(3)more cells in G1 phase;(4)lower expression of p-AKT,p-ERK andα-SMA,higher expression of ECadherin and Claudin-1.PI3 K/AKT inhibitor LY294002 and ERK inhibitor U0126 decreased the expression of p-AKT,p-ERK andα-SMA,and increased the expression of E-Cadherin and Claudin-1.Conclusion Dex can attenuate high glucose-induced HK-2 epithelial-mesenchymal transition by inhibiting AKT and ERK.展开更多
Diabetic cardiomyopathy(DCM)is one of the major heart complications of diabetic patients.Hydrogen sulfide(H2S)is now recognized as an important signaling molecule and has been shown to attenuate the development of dia...Diabetic cardiomyopathy(DCM)is one of the major heart complications of diabetic patients.Hydrogen sulfide(H2S)is now recognized as an important signaling molecule and has been shown to attenuate the development of diabetic cardiomyopathy.However,the underlying mechanisms linking H2S and the development of DCM have not been fully elucidated.In the present study,we therefore sought to explore the role and mechanism of H2S in the pathogenesis of DCM by establishing high glucose-induced injury model in neonatal rat cardiomyocytes(NRCMs)and H9c2 cells.Using cystathionine gamma-lyase(CSE)overexpression and CSE interference vectors transfection,the cell viability,cell apoptosis,and oxidative stress were determined and compared between the treatment of high glucose induction and exgenous NaHS administration.Meanwhile,the relationship between the CSE/H2S system and Wnt/beta-catenin pathway was analyzed and discussed in the high glucose-induced cardiomyocytes.Our results indicated that H2S played an important protective role in high glucose-induced apoptosis and oxidative stress in cardiomyocytes,as shown by the decreased reactive oxygen species and malondialdehyde levels,and the increased activities of superoxide dismutase,catalase and glutathione peroxidase.Moreover,H:S could attenuate the Wnt/p-catenin signalling pathway and up-regulate the expression of haem oxygenase-1(HO-1)and NAD(P)H:quinone oxidoreductase 1(NQOl)in the diabetic myocardium cells.Together,these results demonstrated that H2S could attenuate high glucoseinduced myocardial injury in rat cardiomyocytes by suppressing Wnt/p-catenin pathway.展开更多
Objective The aim of this study was to determine if isoflavone genistien has protective effects against high glucose-induced cell apoptosis in human aortic endlthelial cells, and investigate the possible mechanism for...Objective The aim of this study was to determine if isoflavone genistien has protective effects against high glucose-induced cell apoptosis in human aortic endlthelial cells, and investigate the possible mechanism for this protection. Methods Human aortic endothelial cells subjected to normal (5mmol/L) or high glucose (25mmol/L) were treated with genistein at 0, 50, 100nmol/L. Parallel experiments were performed with 100nM 17b-estradiol, and also in the presence and absence of the pure anti-estrogen ICI-182,780 (100nmol/L). The effects on cell apoptotic DNA fragmentation were determined using cell death ELISA, and the effects on cellular proliferation were determined using tritiated thymidine incorporation assay. Estrogen receptor expression was detected by Taqman quantitative PCR. Results Genistein at 100nmol/L significantly reduced high glucose-induced DNA fragmentation, and reversed cell DNA synthesis inhibition (P <0.001) after 24 hours' incubation. The effect of genistein was completely blocked by ICI-182,780 administration. Estrogen receptor beta, but not alpha was found to be expressed in these cells. Conclusion Isoflavone genistein shows protection against high glucose-induced cell damage through estrogen receptor beta, reducing apoptotic DNA damage and protecting from the inhibition of cell proliferation.展开更多
Objective:To investigate the role of baicalein in phenotypic transformation of vascularsmooth muscle cells induced by high glucose.Methods:Rat vascular smooth muscle cellexperiments were divided into control group,bai...Objective:To investigate the role of baicalein in phenotypic transformation of vascularsmooth muscle cells induced by high glucose.Methods:Rat vascular smooth muscle cellexperiments were divided into control group,baicalein group,high glucose group,highglucose plus baicalein group,real time quantitative PCR were used for mRNA analysis of-SMA,SM22-αnd OPN,Western blot were used for protein analysis of α-SMA,SM22-αand OPN.Results:Comparing the high glucose group and the high glucose plus baicaleingroup,the level of α-SMA mRNA in high glucose group was 0.419±0.090,the level ofα-SMA mRNA in high glucose plus baicalein group was 0.699±0.079,the latter was 66.8%higher than the former.The level of α-SMA protein in high glucose group was 0.213±0.034,the level of α-SMA protein in high glucose plus baicalein group was 0.393±0.062,the latterwas 84.5%higher than the former.Baicalein could significantly inhibit the down-regulationof α-SMA gene expression induced by high glucose(P<0.05).Comparing the high glucosegroup and the high glucose plus baicalein group,the level of SM22-mRNA in high glucosegroup was 0.369±0.063,the level of SM22-α mRNA in high glucose plus baicalein groupwas 0.583±0.049,the latter was 58.0%higher than the former.The level of SM22-α proteinin high glucose group was 0.343±0.047,the level of SM22-protein in high glucose plusbaicalein group was 0.486±0.051,the latter was 41.7%higher than the former.Baicaleincould significantly inhibit the down-regulation of SM22-α gene expression induced by highglucose(P<0.05).Comparing the high glucose group and the high glucose plus baicaleingroup,the level of OPN mRNA in high glucose group was 2.023±0.281,the level of OPNmRNA in high glucose plus baicalein group was 1.511±0.091,the latter was 25.3%lowerthan the former.The level of OPN protein in high glucose group was 1.063±0.132,the levelof OPN protein in high glucose plus baicalein group was 0.761±0.089,the latter was 28.4%lower than the former.Baicalein could significantly inhibit the up-regulation of OPN geneexpression induced by high glucose(P<0.05).Conclusion:Baicalein can significantly inhibitthe high glucose-induced phenotypic transformation of vascular smooth muscle cells fromcontractile phenotype to synthetic phenotype.展开更多
Previous reports have suggested that Ang-(1-7)may have a protective effect in endothelial cells against high glucose(HG)-induced cell injury thanks to a modulatory mechanism in the NF-κB signaling pathway.In this stu...Previous reports have suggested that Ang-(1-7)may have a protective effect in endothelial cells against high glucose(HG)-induced cell injury thanks to a modulatory mechanism in the NF-κB signaling pathway.In this study,we have examined whether NF-κB-IL-1βand Heme oxygenase-1(HO-1)pathways contribute to the protection of Ang-(1-7)against hyperglycemia-induced inflammation and oxidative stress in human umbilical vein endothelial cells(HUVECs).Our results indicate that time-varying exposures of HUVECs,from 1 h to 24 h,to high glucose concentrations result in an increased expression of phosphorylated(p)-p65 and HO-1 in a time-dependent manner.As an inhibitor of NF-κB,pyrrolidinedithiocarbamic acid(PDTC)suppressed IL-1βproduction induced by HG.Of note,HUVECs previously treated with Ang-(1-7)(2μM)for 30 min before being exposed to HG concentrations significantly ameliorated the HG-increased in p-p65 and IL-1βexpression;whereas obviously up-regulated the level of HO-1,along with inhibition of oxidative stress,inflammation,and the HG-induced cytotoxicity.Importantly,when HUVECs were previously treated either with PDTC or IL-1Ra for 30 min before being exposed to HG,it significantly prevented damages caused by high glucose concentrations mentioned above,while the treatment of HO-1 inhibitor Sn-protoporphyrin(SnPP)before exposure to both HG and Ang-(1-7)significantly blocked the protective effect exerted by Ang-(1-7)on endothelial cells against injuries induced by HG mentioned above.To conclude,the data of this study showed that activation and inhibition of the NF-κB-IL-1βpathway and HO-1 pathway may constitute an important defense mechanism against endothelial cell damage caused by HG concentrations.We additionally gave new evidence showing that exogenous Ang-(1-7)exerts a protective effect on HUVECs against the HG-induced cell injury via the inhibition and the activation of the NF-κB-IL-1βpathway and the HO-1 pathway,respectively.展开更多
Objective: To study the protective effect and molecular mechanism of glucagon-like peptide-1 (GLP-1) on the high glucose-induced endothelial cell injury. Methods: Endothelial cells HUVECs were cultured and divided int...Objective: To study the protective effect and molecular mechanism of glucagon-like peptide-1 (GLP-1) on the high glucose-induced endothelial cell injury. Methods: Endothelial cells HUVECs were cultured and divided into three groups, control group were treated with serum-free low-glucose culture medium, high glucose group were treated with serum-free culture medium containing 40 mmol/L glucose and GLP-1 group were treated with serum-free culture medium containing 10 mmol/L GLP-1 and 40 mmol/L glucose. 24 h after treatment, the expression of apoptosis genes and autophagy genes as well as the levels of oxidative stress products and antioxidants were measured. Results: JAK2, STAT3, Bax, Caspase-9, Caspase-3, Nrf2, NQO1, HO1 and GSH-Px mRNA expression as well as ROS, gp91phox, MDA and ox-LDL levels in high glucose group of cells were significantly higher than those in control group while STSQM1, Atg-5 and LC-3 mRNA expression were significantly lower than those of control group;JAK2, STAT3, Bax, Caspase-9 and Caspase-3 mRNA expression as well as ROS, gp91phox, MDA and ox-LDL levels in GLP-1 group of cells were significantly lower than those in high glucose group while Nrf2, NQO1, HO1, GSH-Px, STSQM1, Atg-5 and LC-3mRNA expression were significantly higher than those in high glucose group. Conclusion:GLP-1 can reduce the high glucose-induced endothelial cell injury by inhibiting apoptosis, reducing oxidative stress and enhancing autophagy.展开更多
Objective To investigate whether exogenous hydrogen sulfide(H2S)protects high glucose(HG)-inducedH9c2 cardiomyocyte injury and inflammation response by inhibiting reactive oxygen species(ROS)-Toll-like receptor ...Objective To investigate whether exogenous hydrogen sulfide(H2S)protects high glucose(HG)-inducedH9c2 cardiomyocyte injury and inflammation response by inhibiting reactive oxygen species(ROS)-Toll-like receptor 4(TLR4)pathway.Methods Cell counter kit-8(CCK-8)assay was used to measure the cell viability,展开更多
Background Endothelial cell senescence is accelerated under high glucose condition, which may contribute to the vascular complications in the diabetics, tt has been proved that aspirin has multiple cytoprotective effe...Background Endothelial cell senescence is accelerated under high glucose condition, which may contribute to the vascular complications in the diabetics, tt has been proved that aspirin has multiple cytoprotective effects. This study aimed to investigate the effect of aspirin on high glucose-induced endothelial cell senescence and its possible mechanism. Methods Human umbilical venous endothelial cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with different treatments including the normal glucose (5.5 mmol/L), high glucose (33 mmol/L) and aspirin (0.01-1.00 mmol/L) with high glucose. And 300 umol/L L-NAME was added to the culture medium when needed. After 48 hours, SA-13-gal staining was used to evaluate the senescence. Total nitric oxide (NO) production and NO synthase (NOS) activity were measured using Griess reaction and molecular probes of 3-amino-4-aminomethyl-2', 7'- difluorescein, diacetate. The level of intracellular reactive oxygen species was monitored by flow cytometry using 2', 7'-dichlorofluorescein diacetate. Endothelial NOS (eNOS), caveolin-1 protein expressions and caveolin-1/eNOS interaction were analyzed by immunoblotting and immunoprecipitation respectively. Asymmetric dimethylarginine (ADMA) concentration was determined by high-performance liquid chromatography. Results Exposure to 33 mmol/L glucose for 48 hours significantly increased the number of SA-13-gal positive cells. Co-incubation with aspirin markedly inhibited SA-13-gal activity dose-dependently. Aspirin increased NOS activity with eNOS protein expression unchanged and increased NO levels and alleviated oxidative stress. Consistent with these findings, caveolin-1 expression, caveolin-1/eNOS interaction and ADMA accumulation were also decreased. All the inhibitory effects of aspirin on senescence were completely obliterated by L-NAME, the NOS inhibitor. Conclusion The anti-senescent effects of aspirin are fulfilled by increasing NO production via the up-regulation of NOS activity and preventing caveolin-1 expression, caveolin-1/eNOS interaction and ADMA accumulation.展开更多
Objective: To examine the mechanism underlying the beneficial role of cinnamaldehyde on oxidative damage and apoptosis in high glucose (HG)-induced dorsal root ganglion (DRG) neurons in vitro. Methods: HG-treate...Objective: To examine the mechanism underlying the beneficial role of cinnamaldehyde on oxidative damage and apoptosis in high glucose (HG)-induced dorsal root ganglion (DRG) neurons in vitro. Methods: HG-treated DRG neurons were developed as an in vitro model of diabetic neuropathy. The neurons were randomly divided into five groups: the control group, the HG group and the HG groups treated with 25, 50 and 100 nmol/L cinnamaldehyde, respectively. Cell viability was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay and apoptosis rate was evaluated by the in situ TdT-mediated dUTP nick end labeling (TUNEL) assay. The intracellular level of reactive oxygen species (ROS) was measured with flow cytometry. Expression of nuclear factor-kappa B (NF-κ B), inhibitor of κ B (I κ B), phosphorylated I κ B (p-IκB), tumor necrosis factor (TNF)-α, interleukin-6 (IL-6) and caspase-3 were determined by western blotting and real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). Expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and hemeoxygenase-1 (HO-1) were also measured by western blotting. Results: Cinnamaldehyde reduced HG-induced loss of viability, apoptosis and intracellular generation of ROS in the DRG neurons via inhibiting NF- K B activity. The western blot assay results showed that the HG-induced elevated expressions of NF- κB, I κ B and p-I κ B were remarkably reduced by cinnamaldehyde treatment in a dose-dependent manner (P〈0.01). The HG-induced over-expression of NF-κ B p65 mRNA was remarkably attenuated after cinnamaldehyde treatment in a dose-dependent manner (P〈0.01). However, the expressions of Nrf2 and HO-1 were not upregulated. Treatment with cinnamaldehyde not only attenuated caspase-3 activation and the caspase cleavage cascade in DRG neurons, but also lowered the elevated IL-6, TNF-α, cyclo-oxygenase and inducible nitric oxide synthase levels, indicating a reduction in inflammatory damage. Conclusions: Cinnamaldehyde protected DRG neurons from the deleterious effects of HG through inactivation of NF- κB pathway but not through activation of Nrf2/HO-1. And thus cinnamaldehyde may have potential application as a treatment for DPN.展开更多
High glucose affects primary afferent neurons in dorsal root ganglia by inhibiting neurite elongation,causing oxidative stress,and inducing neuronal apoptosis and mitochondrial dysfunction,which finally result in neur...High glucose affects primary afferent neurons in dorsal root ganglia by inhibiting neurite elongation,causing oxidative stress,and inducing neuronal apoptosis and mitochondrial dysfunction,which finally result in neuronal damage.Proanthocyanidin,a potent antioxidant,has been shown to have neuroprotective effects.Proanthocyanidin B2 is a common dimer of oligomeric proanthocyanidins.To date,no studies have reported the neuroprotective effects of proanthocyanidin B2 against high-glucose-related neurotoxicity in dorsal root ganglion neurons.In this study,10 μg/m L proanthocyanidin B2 was used to investigate its effect on 45 m M high-glucose-cultured dorsal root ganglion neurons.We observed that challenge with high levels of glucose increased neuronal reactive oxygen species and promoted apoptosis,decreased cell viability,inhibited outgrowth of neurites,and decreased growth-associated protein 43 protein and m RNA levels.Proanthocyanidin B2 administration reversed the neurotoxic effects caused by glucose challenge.Blockage of the phosphatidylinositol 3 kinase/Akt signaling pathway with 10 μM LY294002 eliminated the protective effects of proanthocyanidin B2.Therefore,proanthocyanidin B2 might be a potential novel agent for the treatment of peripheral diabetic neuropathy.展开更多
The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian in...The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian influenza virus in vaccinated birds would evolve more rapidly and pose a greater risk to humans.In this review,we summarize the successes in controlling highly pathogenic avian influenza in China and make suggestions regarding the requirements for vaccine selection and effectiveness.In addition,we present evidence that vaccination of poultry not only eliminates human infection with avian influenza virus,but also significantly reduces and abolishes some harmful characteristics of avian influenza virus.展开更多
High-temperature stress threatens the growth and yield of crops. Basic helix-loop-helix(bHLH) transcription factors(TFs) have been shown to play important roles in regulating high-temperature resistance in plants. How...High-temperature stress threatens the growth and yield of crops. Basic helix-loop-helix(bHLH) transcription factors(TFs) have been shown to play important roles in regulating high-temperature resistance in plants. However, the bHLH TFs responsible for high-temperature tolerance in cucumbers have not been identified. We used transcriptome profiling to screen the high temperature-responsive candidate bHLH TFs in cucumber. Here, we found that the expression of 75 CsbHLH genes was altered under high-temperature stress. The expression of the CsSPT gene was induced by high temperatures in TT(Thermotolerant) cucumber plants. However, the Csspt mutant plants obtained by the CRISPR-Cas9 system showed severe thermosensitive symptoms, including wilted leaves with brown margins and reduced root density and cell activity.The Csspt mutant plants also exhibited elevated H_(2)O_(2) levels and down-regulated photosystem-related genes under normal conditions.Furthermore, there were high relative electrolytic leakage(REC), malondialdehyde(MDA), glutathione(GSH), and superoxide radical(O_(2)^(·-)) levels in the Csspt mutant plants, with decreased Proline content after the high-temperature treatment. Transcriptome analysis showed that the photosystem and chloroplast activities in Csspt mutant plants were extremely disrupted by the high-temperature stress compared with wildtype(WT) plants. Moreover, the plant hormone signal transduction, as well as MAPK and calcium signaling pathways were activated in Csspt mutant plants under high-temperature stress. The HSF and HSP family genes shared the same upregulated expression patterns in Csspt and WT plants under high-temperature conditions. However, most bHLH, NAC, and bZIP family genes were significantly down-regulated by heat in Csspt mutant plants. Thus, these results demonstrated that CsSPT regulated the high-temperature response by recruiting photosynthesis components, signaling pathway molecules, and transcription factors. Our results provide important insights into the heat response mechanism of CsSPT in cucumber and its potential as a target for breeding heat-resistant crops.展开更多
Methods We examined the expression of osteoprotegerin in hPDL cells cultured at different concentrations of glucose using real-time polymerase chain reaction (PCR), and Western blotting analysis. AMPK phosphorylatio...Methods We examined the expression of osteoprotegerin in hPDL cells cultured at different concentrations of glucose using real-time polymerase chain reaction (PCR), and Western blotting analysis. AMPK phosphorylation in hPDL cells was studied using immunoprecipitate kinase assay and Western blotting. The effect of AMPK activation on RANKL expression in hPDL cells was investigated by real-time PCR and Western blotting. Results High glucose levels caused an increase in RANKL mRNA and protein expression in hPDL cells. Moreover, the amount of p-AMPK and AMPK activity was lower in hPDL cells exposed to high glucose levels than in cells exposed to normal glucose levels. Suppression of AMPK by Compound C augmented RANKL expression, and AMPK activation by metformin significantly decreased RANKL expression in hPDL cells. Additionally, metformin down-regulated RANKL expression in hPDL cells exposed to high glucose via AMPK activation. Conclusion High glucose-induced up-regulation of RANKL could be due to decreased AMPK activity, and AMPK activation may be involved in regulating of RANKL expression in hPDL cells.展开更多
Microwave-assisted mechanical excavation has great application prospects in mines and tunnels,but there are few field experiments on microwave-assisted rock breaking.This paper takes the Sishanling iron mine as the re...Microwave-assisted mechanical excavation has great application prospects in mines and tunnels,but there are few field experiments on microwave-assisted rock breaking.This paper takes the Sishanling iron mine as the research object and adopts the self-developed high-power microwave-induced fracturing test system for hard rock to conduct field experiments of microwave-induced fracturing of iron ore.The heating and reflection evolution characteristics of ore under different microwave parameters(antenna type,power,and working distance)were studied,and the optimal microwave parameters were obtained.Subsequently,the ore was irradiated with the optimal microwave parameters,and the cracking effect of the ore under the action of the high-power open microwave was analyzed.The results show that the reflection coefficient(standing wave ratio)can be rapidly(<5 s)and automatically adjusted below the preset threshold value(1.6)as microwave irradiation is performed.When using a right-angle horn antenna with a working distance of 5 cm,the effect of automatic reflection adjustment reaches the best among other antenna types and working distances.When the working distance is the same,the average temperature of the irradiation surface and the area of the high-temperature area under the action of the two antennas(right-angled and equal-angled horn antenna)are basically the same and decrease with the increase of working distance.The optimal microwave parameters are:a right-angle horn antenna with a working distance of 5 cm.Subsequently,in further experiments,the optimal parameters were used to irradiate for 20 s and 40 s at a microwave power of 60 kW,respectively.The surface damage extended 38 cm×30 cm and 53 cm×30 cm,respectively,and the damage extended to a depth of about 50 cm.The drilling speed was increased by 56.2%and 66.5%,respectively,compared to the case when microwaves were not used.展开更多
基金Supported by Medical and Health Science and Technology Project of Zhejiang Province(No.2023KY1356).
文摘AIM:To evaluate the effects of LIN28A(human)on high glucose-induced retinal pigmented epithelium(RPE)cell injury and its possible mechanism.METHODS:Diabetic retinopathy model was generated following 48h of exposure to 30 mmol/L high glucose(HG)in ARPE-19 cells.Quantitative real-time polymerase chain reaction(qRT-PCR)and Western blot tested the expression of the corresponding genes and proteins.Cell viability as well as apoptosis was determined through cell counting kit-8(CCK-8)and flow cytometry assays.Immunofluorescence assay was adopted to evaluate autophagy activity.Caspase 3 activity,oxidative stress markers,and cytokines were appraised adopting their commercial kits,respectively.Finally,ARPE-19 cells were preincubated with EX527,a Sirtuin 1(SIRT1)inhibitor,prior to HG stimulation to validate the regulatory mechanism.RESULTS:LIN28A was downregulated in HG-challenged ARPE-19 cells.LIN28A overexpression greatly inhibited HGinduced ARPE-19 cell viability loss,apoptosis,oxidative damage as well as inflammatory response.Meanwhile,the repressed autophagy and SIRT1 in ARPE-19 cells challenged with HG were elevated after LIN28A overexpression.In addition,treatment of EX527 greatly inhibited the activated autophagy following LIN28A overexpression and partly abolished the protective role of LIN28A against HG-elicited apoptosis,oxidative damage as well as inflammation in ARPE-19 cells.CONCLUSION:LIN28A exerts a protective role against HG-elicited RPE oxidative damage,inflammation,as well as apoptosis via regulating SIRT1/autophagy.
文摘Objective:To explore the regulatory mechanism of transient receptor potential melastatin-7(TRPM7)in high glucose-induced renal tubular epithelial cell injury.Methods:The expression of TRPM7 in the serum of diabetic nephropathy patients and high glucose-induced HK-2 cells was detected by RT-qPCR.Then,the TRPM7 interference vector was constructed,and the downstream high mobility group box 1(HMGB1)/Toll-like receptor 4(TLR4)signaling pathway proteins were detected.Next,in addition to interference with TRPM7 expression,overexpression of HMGB1 in high glucose-induced HK-2 cells was performed.Cell activity,apoptosis,oxidative stress levels,and inflammation levels were determined by CCK8,TUNEL,Western blotting,immunofluorescence and related kits.Results:TRPM7 expression was upregulated in the serum of diabetic nephropathy patients and high glucose-induced HK-2 cells.Interference with TRPM7 reduced cell damage,epithelial-mesenchymal transition,oxidative stress,and inflammatory response in high glucose-induced HK-2 cells via inhibiting the HMGB1/TLR4 signaling pathway.However,the effects induced by TRPM7 silencing were abrogated by HMGB1 overexpression.Conclusions:Decreased TRPM7 alleviates high glucose-induced renal tubular epithelial cell injury by inhibiting the HMGB1/TLR4 signaling pathway.Further animal experiments and clinical trials are warranted to verify its effect.
文摘MicroRNAs(miRNAs) are endogenous 20 -23 -nucleotide (nt) -containing small non-coding RNAs that negatively regulate gene expression in diverse biological and pathological processes,including cell differentiation,proliferation, apoptosis,heart disease and human cancers.We investigated miR-133 expression and its potential role in a high glucose-induced myocardium in Streptozotocin(STZ)-induced C57bl6 mouse model of diabetes.miR-133 expression was significantly increased in myocardium in a time-dependent manner after STZ treatment.IGF1 receptor(IGF1R) protein was dramatically decreased without obvious up-regulation of its mRNA level post hyperglycemia.IGF1R protein level was decreaed with increase of its transcript level in neonatal mouse ventricular cardiomyocytes induced by high D-glucose concentration. Dual luciferase assay revealed that miR133 could interact with specific sites in the 3’UTR of IGF1R gene.p-ERK and p-Akt levels were reduced in neonatal mouse cardiomyocytes over-expressed with miR133 after IGF treatment.Introduction of functional miR-133,IGF1R siRNA into neonatal mouse cardiomyocytes could enhance cardiomyocyte apoptosis.These results implicate that miR-133 is involved in contributing to high glucose-induced cardiomyocyte apoptosis via regulating IGF1R expression post-transcriptionally.
基金supported by grants from Hubei Natural Science Foundation of China(No.2012FFB04307)Wuhan University Independent Research Projects Foundation(No.303274034)+1 种基金Zhongnan Hospital of Wuhan University Hospital Foundation(No.201103)National Natural Science Foundation of China(No.390971103)
文摘Hyperglycemia is an important initiator of cardiovascular disease, contributing to the de- velopment of cardiomyocyte death and diabetic complications. The purpose of the present study was to investigate whether high glucose state could induce apoptosis of rat cardiomyocyte cell line H9c2 through microRNA-mediated Bcl-2 signaling pathway. The expression of miR-34a and Bcl-2 mRNA was detected by using real-time PCR. Western blotting was used to examine the changes in apop- tosis-associated protein Bcl-2. Apoptosis of H9c2 cells was tested by using flow cytometry. The results showed that the expression of miR-34a was significantly elevated and that of Bcl-2 was strongly re- duced, and apoptosis of cardiomyocytes was apparently increased in the high-glucose-treated H9c2 cells as compared with normal-glucose-treated controls. In addition, we identified Bcl-2 gene was the target of miR-34a, miR-34a mimics reduced the expression of Bcl-2 and increased glucose-induced apoptosis, but miR-34a inhibitor acted as the opposite mediator. Our data demonstrate that miR-34a contributes to high glucose-induced decreases in Bcl-2 expression and subsequent cardiomyocyte apoptosis.
基金supported by the National Natural Science Foundation of China,No.30572438the Beijing Science Nuture Foundation,No.7132189a grant from Science Foundation of Peking Union Medical College Hospital,No.2013-098
文摘Quercetin can reverse high glucose-induced inhibition of neural cell proliferation, and therefore may have a neuroprotective effect in diabetic peripheral neuropathy. It is difficult to obtain pri- mary Schwann cells and RSC96 cells could replace primary Schwann cells in studies of the role of autophagy in the mechanism underlying diabetic peripheral neuropathy. Here, we show that under high glucose conditions, there are fewer autophagosomes in immortalized rat RSC96 cells and primary rat Schwann ceils than under control conditions, the proliferative activity of both cell types is significantly impaired, and the expression of Berlin- 1 and LC3, the molecular mark- ers for autophagy, is significantly lower. After intervention with quercetin, the autophagic and proliferative activity of both cell types is rescued. These results suggest that quercetin can allevi- ate high glucose-induced damage to Schwann cells by autophagy.
文摘Objective To explore the protective effects of dexmedetomidine(Dex)against high glucose-induced epithelial-mesenchymal transition in HK-2 cells and relevant mechanisms.Methods HK-2 cells were exposed to either glucose or glucose+Dex for 6 h.The production of ROS,morphology of HK-2 cells,and cell cycle were detected.Moreover,the expression of AKT,p-AKT,ERK,pERK,PI3 K,E-Cadherin,Claudin-1,andα-SMA were determined and compared between HK-2 cells exposed to glucose and those exposed to both glucose and Dex with or without PI3 K/AKT pathway inhibitor LY294002 and ERK pathway inhibitor U0126.Results Compared with HK-2 cells exposed to high level of glucose,the HK-2 cells exposed to both high level of glucose and Dex showed:(1)lower level of ROS production;(2)cell morphology was complete;(3)more cells in G1 phase;(4)lower expression of p-AKT,p-ERK andα-SMA,higher expression of ECadherin and Claudin-1.PI3 K/AKT inhibitor LY294002 and ERK inhibitor U0126 decreased the expression of p-AKT,p-ERK andα-SMA,and increased the expression of E-Cadherin and Claudin-1.Conclusion Dex can attenuate high glucose-induced HK-2 epithelial-mesenchymal transition by inhibiting AKT and ERK.
基金the Natural Science Foundation of Hubei Province of China(No.2011CDC146).
文摘Diabetic cardiomyopathy(DCM)is one of the major heart complications of diabetic patients.Hydrogen sulfide(H2S)is now recognized as an important signaling molecule and has been shown to attenuate the development of diabetic cardiomyopathy.However,the underlying mechanisms linking H2S and the development of DCM have not been fully elucidated.In the present study,we therefore sought to explore the role and mechanism of H2S in the pathogenesis of DCM by establishing high glucose-induced injury model in neonatal rat cardiomyocytes(NRCMs)and H9c2 cells.Using cystathionine gamma-lyase(CSE)overexpression and CSE interference vectors transfection,the cell viability,cell apoptosis,and oxidative stress were determined and compared between the treatment of high glucose induction and exgenous NaHS administration.Meanwhile,the relationship between the CSE/H2S system and Wnt/beta-catenin pathway was analyzed and discussed in the high glucose-induced cardiomyocytes.Our results indicated that H2S played an important protective role in high glucose-induced apoptosis and oxidative stress in cardiomyocytes,as shown by the decreased reactive oxygen species and malondialdehyde levels,and the increased activities of superoxide dismutase,catalase and glutathione peroxidase.Moreover,H:S could attenuate the Wnt/p-catenin signalling pathway and up-regulate the expression of haem oxygenase-1(HO-1)and NAD(P)H:quinone oxidoreductase 1(NQOl)in the diabetic myocardium cells.Together,these results demonstrated that H2S could attenuate high glucoseinduced myocardial injury in rat cardiomyocytes by suppressing Wnt/p-catenin pathway.
文摘Objective The aim of this study was to determine if isoflavone genistien has protective effects against high glucose-induced cell apoptosis in human aortic endlthelial cells, and investigate the possible mechanism for this protection. Methods Human aortic endothelial cells subjected to normal (5mmol/L) or high glucose (25mmol/L) were treated with genistein at 0, 50, 100nmol/L. Parallel experiments were performed with 100nM 17b-estradiol, and also in the presence and absence of the pure anti-estrogen ICI-182,780 (100nmol/L). The effects on cell apoptotic DNA fragmentation were determined using cell death ELISA, and the effects on cellular proliferation were determined using tritiated thymidine incorporation assay. Estrogen receptor expression was detected by Taqman quantitative PCR. Results Genistein at 100nmol/L significantly reduced high glucose-induced DNA fragmentation, and reversed cell DNA synthesis inhibition (P <0.001) after 24 hours' incubation. The effect of genistein was completely blocked by ICI-182,780 administration. Estrogen receptor beta, but not alpha was found to be expressed in these cells. Conclusion Isoflavone genistein shows protection against high glucose-induced cell damage through estrogen receptor beta, reducing apoptotic DNA damage and protecting from the inhibition of cell proliferation.
基金Hainan Provincial Natural Science Foundation of China(No.817141)National Natural Science Foundation of China(No.81460043).
文摘Objective:To investigate the role of baicalein in phenotypic transformation of vascularsmooth muscle cells induced by high glucose.Methods:Rat vascular smooth muscle cellexperiments were divided into control group,baicalein group,high glucose group,highglucose plus baicalein group,real time quantitative PCR were used for mRNA analysis of-SMA,SM22-αnd OPN,Western blot were used for protein analysis of α-SMA,SM22-αand OPN.Results:Comparing the high glucose group and the high glucose plus baicaleingroup,the level of α-SMA mRNA in high glucose group was 0.419±0.090,the level ofα-SMA mRNA in high glucose plus baicalein group was 0.699±0.079,the latter was 66.8%higher than the former.The level of α-SMA protein in high glucose group was 0.213±0.034,the level of α-SMA protein in high glucose plus baicalein group was 0.393±0.062,the latterwas 84.5%higher than the former.Baicalein could significantly inhibit the down-regulationof α-SMA gene expression induced by high glucose(P<0.05).Comparing the high glucosegroup and the high glucose plus baicalein group,the level of SM22-mRNA in high glucosegroup was 0.369±0.063,the level of SM22-α mRNA in high glucose plus baicalein groupwas 0.583±0.049,the latter was 58.0%higher than the former.The level of SM22-α proteinin high glucose group was 0.343±0.047,the level of SM22-protein in high glucose plusbaicalein group was 0.486±0.051,the latter was 41.7%higher than the former.Baicaleincould significantly inhibit the down-regulation of SM22-α gene expression induced by highglucose(P<0.05).Comparing the high glucose group and the high glucose plus baicaleingroup,the level of OPN mRNA in high glucose group was 2.023±0.281,the level of OPNmRNA in high glucose plus baicalein group was 1.511±0.091,the latter was 25.3%lowerthan the former.The level of OPN protein in high glucose group was 1.063±0.132,the levelof OPN protein in high glucose plus baicalein group was 0.761±0.089,the latter was 28.4%lower than the former.Baicalein could significantly inhibit the up-regulation of OPN geneexpression induced by high glucose(P<0.05).Conclusion:Baicalein can significantly inhibitthe high glucose-induced phenotypic transformation of vascular smooth muscle cells fromcontractile phenotype to synthetic phenotype.
基金supported by the Technology Planning Project of Huangpu District(201544-01)Medical Scientific Research Foundation of Guangdong Province(A2015287)+2 种基金Science and Technology Planning Project of Guangdong Province(2017ZC0474)Natural Science Foundation of Guangdong Province(2015A030313690)General Project of Dongguan City(Nos.201950715024922 and 2018507150241344).
文摘Previous reports have suggested that Ang-(1-7)may have a protective effect in endothelial cells against high glucose(HG)-induced cell injury thanks to a modulatory mechanism in the NF-κB signaling pathway.In this study,we have examined whether NF-κB-IL-1βand Heme oxygenase-1(HO-1)pathways contribute to the protection of Ang-(1-7)against hyperglycemia-induced inflammation and oxidative stress in human umbilical vein endothelial cells(HUVECs).Our results indicate that time-varying exposures of HUVECs,from 1 h to 24 h,to high glucose concentrations result in an increased expression of phosphorylated(p)-p65 and HO-1 in a time-dependent manner.As an inhibitor of NF-κB,pyrrolidinedithiocarbamic acid(PDTC)suppressed IL-1βproduction induced by HG.Of note,HUVECs previously treated with Ang-(1-7)(2μM)for 30 min before being exposed to HG concentrations significantly ameliorated the HG-increased in p-p65 and IL-1βexpression;whereas obviously up-regulated the level of HO-1,along with inhibition of oxidative stress,inflammation,and the HG-induced cytotoxicity.Importantly,when HUVECs were previously treated either with PDTC or IL-1Ra for 30 min before being exposed to HG,it significantly prevented damages caused by high glucose concentrations mentioned above,while the treatment of HO-1 inhibitor Sn-protoporphyrin(SnPP)before exposure to both HG and Ang-(1-7)significantly blocked the protective effect exerted by Ang-(1-7)on endothelial cells against injuries induced by HG mentioned above.To conclude,the data of this study showed that activation and inhibition of the NF-κB-IL-1βpathway and HO-1 pathway may constitute an important defense mechanism against endothelial cell damage caused by HG concentrations.We additionally gave new evidence showing that exogenous Ang-(1-7)exerts a protective effect on HUVECs against the HG-induced cell injury via the inhibition and the activation of the NF-κB-IL-1βpathway and the HO-1 pathway,respectively.
基金Surface Project of National Natural Science Foundation of China,No:81570440Shanghai Leading Talent Fund Project,No.:035.
文摘Objective: To study the protective effect and molecular mechanism of glucagon-like peptide-1 (GLP-1) on the high glucose-induced endothelial cell injury. Methods: Endothelial cells HUVECs were cultured and divided into three groups, control group were treated with serum-free low-glucose culture medium, high glucose group were treated with serum-free culture medium containing 40 mmol/L glucose and GLP-1 group were treated with serum-free culture medium containing 10 mmol/L GLP-1 and 40 mmol/L glucose. 24 h after treatment, the expression of apoptosis genes and autophagy genes as well as the levels of oxidative stress products and antioxidants were measured. Results: JAK2, STAT3, Bax, Caspase-9, Caspase-3, Nrf2, NQO1, HO1 and GSH-Px mRNA expression as well as ROS, gp91phox, MDA and ox-LDL levels in high glucose group of cells were significantly higher than those in control group while STSQM1, Atg-5 and LC-3 mRNA expression were significantly lower than those of control group;JAK2, STAT3, Bax, Caspase-9 and Caspase-3 mRNA expression as well as ROS, gp91phox, MDA and ox-LDL levels in GLP-1 group of cells were significantly lower than those in high glucose group while Nrf2, NQO1, HO1, GSH-Px, STSQM1, Atg-5 and LC-3mRNA expression were significantly higher than those in high glucose group. Conclusion:GLP-1 can reduce the high glucose-induced endothelial cell injury by inhibiting apoptosis, reducing oxidative stress and enhancing autophagy.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 81530099, 81573763 and 81773932), the Beijing Municipal Natural Science Foundation (Grant No.7172221), and the National Key Technology R&D Program "New Drug Innovation" of China (Grant No. 2016YFE0116200).
文摘Objective To investigate whether exogenous hydrogen sulfide(H2S)protects high glucose(HG)-inducedH9c2 cardiomyocyte injury and inflammation response by inhibiting reactive oxygen species(ROS)-Toll-like receptor 4(TLR4)pathway.Methods Cell counter kit-8(CCK-8)assay was used to measure the cell viability,
文摘Background Endothelial cell senescence is accelerated under high glucose condition, which may contribute to the vascular complications in the diabetics, tt has been proved that aspirin has multiple cytoprotective effects. This study aimed to investigate the effect of aspirin on high glucose-induced endothelial cell senescence and its possible mechanism. Methods Human umbilical venous endothelial cells were cultured in Dulbecco's modified Eagle's medium (DMEM) with different treatments including the normal glucose (5.5 mmol/L), high glucose (33 mmol/L) and aspirin (0.01-1.00 mmol/L) with high glucose. And 300 umol/L L-NAME was added to the culture medium when needed. After 48 hours, SA-13-gal staining was used to evaluate the senescence. Total nitric oxide (NO) production and NO synthase (NOS) activity were measured using Griess reaction and molecular probes of 3-amino-4-aminomethyl-2', 7'- difluorescein, diacetate. The level of intracellular reactive oxygen species was monitored by flow cytometry using 2', 7'-dichlorofluorescein diacetate. Endothelial NOS (eNOS), caveolin-1 protein expressions and caveolin-1/eNOS interaction were analyzed by immunoblotting and immunoprecipitation respectively. Asymmetric dimethylarginine (ADMA) concentration was determined by high-performance liquid chromatography. Results Exposure to 33 mmol/L glucose for 48 hours significantly increased the number of SA-13-gal positive cells. Co-incubation with aspirin markedly inhibited SA-13-gal activity dose-dependently. Aspirin increased NOS activity with eNOS protein expression unchanged and increased NO levels and alleviated oxidative stress. Consistent with these findings, caveolin-1 expression, caveolin-1/eNOS interaction and ADMA accumulation were also decreased. All the inhibitory effects of aspirin on senescence were completely obliterated by L-NAME, the NOS inhibitor. Conclusion The anti-senescent effects of aspirin are fulfilled by increasing NO production via the up-regulation of NOS activity and preventing caveolin-1 expression, caveolin-1/eNOS interaction and ADMA accumulation.
基金Supported by the National Natural Science Foundation of China(No.81473639)the Natural Science Foundation of Beijing(No.7122147)
文摘Objective: To examine the mechanism underlying the beneficial role of cinnamaldehyde on oxidative damage and apoptosis in high glucose (HG)-induced dorsal root ganglion (DRG) neurons in vitro. Methods: HG-treated DRG neurons were developed as an in vitro model of diabetic neuropathy. The neurons were randomly divided into five groups: the control group, the HG group and the HG groups treated with 25, 50 and 100 nmol/L cinnamaldehyde, respectively. Cell viability was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay and apoptosis rate was evaluated by the in situ TdT-mediated dUTP nick end labeling (TUNEL) assay. The intracellular level of reactive oxygen species (ROS) was measured with flow cytometry. Expression of nuclear factor-kappa B (NF-κ B), inhibitor of κ B (I κ B), phosphorylated I κ B (p-IκB), tumor necrosis factor (TNF)-α, interleukin-6 (IL-6) and caspase-3 were determined by western blotting and real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). Expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and hemeoxygenase-1 (HO-1) were also measured by western blotting. Results: Cinnamaldehyde reduced HG-induced loss of viability, apoptosis and intracellular generation of ROS in the DRG neurons via inhibiting NF- K B activity. The western blot assay results showed that the HG-induced elevated expressions of NF- κB, I κ B and p-I κ B were remarkably reduced by cinnamaldehyde treatment in a dose-dependent manner (P〈0.01). The HG-induced over-expression of NF-κ B p65 mRNA was remarkably attenuated after cinnamaldehyde treatment in a dose-dependent manner (P〈0.01). However, the expressions of Nrf2 and HO-1 were not upregulated. Treatment with cinnamaldehyde not only attenuated caspase-3 activation and the caspase cleavage cascade in DRG neurons, but also lowered the elevated IL-6, TNF-α, cyclo-oxygenase and inducible nitric oxide synthase levels, indicating a reduction in inflammatory damage. Conclusions: Cinnamaldehyde protected DRG neurons from the deleterious effects of HG through inactivation of NF- κB pathway but not through activation of Nrf2/HO-1. And thus cinnamaldehyde may have potential application as a treatment for DPN.
基金supported by the National Natural Science Foundation of China,No.81501935the Shandong Provincial Natural Science Foundation of China,No.ZR2014HQ065
文摘High glucose affects primary afferent neurons in dorsal root ganglia by inhibiting neurite elongation,causing oxidative stress,and inducing neuronal apoptosis and mitochondrial dysfunction,which finally result in neuronal damage.Proanthocyanidin,a potent antioxidant,has been shown to have neuroprotective effects.Proanthocyanidin B2 is a common dimer of oligomeric proanthocyanidins.To date,no studies have reported the neuroprotective effects of proanthocyanidin B2 against high-glucose-related neurotoxicity in dorsal root ganglion neurons.In this study,10 μg/m L proanthocyanidin B2 was used to investigate its effect on 45 m M high-glucose-cultured dorsal root ganglion neurons.We observed that challenge with high levels of glucose increased neuronal reactive oxygen species and promoted apoptosis,decreased cell viability,inhibited outgrowth of neurites,and decreased growth-associated protein 43 protein and m RNA levels.Proanthocyanidin B2 administration reversed the neurotoxic effects caused by glucose challenge.Blockage of the phosphatidylinositol 3 kinase/Akt signaling pathway with 10 μM LY294002 eliminated the protective effects of proanthocyanidin B2.Therefore,proanthocyanidin B2 might be a potential novel agent for the treatment of peripheral diabetic neuropathy.
基金This work was supported by the National Key Research andDevelopment Programof China(2021YFD1800200 and2021YFC2301700).
文摘The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian influenza virus in vaccinated birds would evolve more rapidly and pose a greater risk to humans.In this review,we summarize the successes in controlling highly pathogenic avian influenza in China and make suggestions regarding the requirements for vaccine selection and effectiveness.In addition,we present evidence that vaccination of poultry not only eliminates human infection with avian influenza virus,but also significantly reduces and abolishes some harmful characteristics of avian influenza virus.
基金supported by grants from the Key Project of Guangzhou (Grant No.202103000085)National Natural Science Foundation of China (Grant No.31902014)+1 种基金Guangzhou Science and Technology Project (Grant No.202102020502)Fruit and Vegetable Industry System Innovation Team Project of Guangdong (Grant No.2021KJ110)。
文摘High-temperature stress threatens the growth and yield of crops. Basic helix-loop-helix(bHLH) transcription factors(TFs) have been shown to play important roles in regulating high-temperature resistance in plants. However, the bHLH TFs responsible for high-temperature tolerance in cucumbers have not been identified. We used transcriptome profiling to screen the high temperature-responsive candidate bHLH TFs in cucumber. Here, we found that the expression of 75 CsbHLH genes was altered under high-temperature stress. The expression of the CsSPT gene was induced by high temperatures in TT(Thermotolerant) cucumber plants. However, the Csspt mutant plants obtained by the CRISPR-Cas9 system showed severe thermosensitive symptoms, including wilted leaves with brown margins and reduced root density and cell activity.The Csspt mutant plants also exhibited elevated H_(2)O_(2) levels and down-regulated photosystem-related genes under normal conditions.Furthermore, there were high relative electrolytic leakage(REC), malondialdehyde(MDA), glutathione(GSH), and superoxide radical(O_(2)^(·-)) levels in the Csspt mutant plants, with decreased Proline content after the high-temperature treatment. Transcriptome analysis showed that the photosystem and chloroplast activities in Csspt mutant plants were extremely disrupted by the high-temperature stress compared with wildtype(WT) plants. Moreover, the plant hormone signal transduction, as well as MAPK and calcium signaling pathways were activated in Csspt mutant plants under high-temperature stress. The HSF and HSP family genes shared the same upregulated expression patterns in Csspt and WT plants under high-temperature conditions. However, most bHLH, NAC, and bZIP family genes were significantly down-regulated by heat in Csspt mutant plants. Thus, these results demonstrated that CsSPT regulated the high-temperature response by recruiting photosynthesis components, signaling pathway molecules, and transcription factors. Our results provide important insights into the heat response mechanism of CsSPT in cucumber and its potential as a target for breeding heat-resistant crops.
基金This study was supported by grants from the National Natural Science Foundation of China (No. 30973354) and the China Postdoctoral Science Foundation (No. 20100471816).
文摘Methods We examined the expression of osteoprotegerin in hPDL cells cultured at different concentrations of glucose using real-time polymerase chain reaction (PCR), and Western blotting analysis. AMPK phosphorylation in hPDL cells was studied using immunoprecipitate kinase assay and Western blotting. The effect of AMPK activation on RANKL expression in hPDL cells was investigated by real-time PCR and Western blotting. Results High glucose levels caused an increase in RANKL mRNA and protein expression in hPDL cells. Moreover, the amount of p-AMPK and AMPK activity was lower in hPDL cells exposed to high glucose levels than in cells exposed to normal glucose levels. Suppression of AMPK by Compound C augmented RANKL expression, and AMPK activation by metformin significantly decreased RANKL expression in hPDL cells. Additionally, metformin down-regulated RANKL expression in hPDL cells exposed to high glucose via AMPK activation. Conclusion High glucose-induced up-regulation of RANKL could be due to decreased AMPK activity, and AMPK activation may be involved in regulating of RANKL expression in hPDL cells.
基金financial support from the National Natural Science Foundation of China(Grant No.41827806)the Liaoning Provincial Science and Technology Program of China(Grant No.2022JH2/101300109).
文摘Microwave-assisted mechanical excavation has great application prospects in mines and tunnels,but there are few field experiments on microwave-assisted rock breaking.This paper takes the Sishanling iron mine as the research object and adopts the self-developed high-power microwave-induced fracturing test system for hard rock to conduct field experiments of microwave-induced fracturing of iron ore.The heating and reflection evolution characteristics of ore under different microwave parameters(antenna type,power,and working distance)were studied,and the optimal microwave parameters were obtained.Subsequently,the ore was irradiated with the optimal microwave parameters,and the cracking effect of the ore under the action of the high-power open microwave was analyzed.The results show that the reflection coefficient(standing wave ratio)can be rapidly(<5 s)and automatically adjusted below the preset threshold value(1.6)as microwave irradiation is performed.When using a right-angle horn antenna with a working distance of 5 cm,the effect of automatic reflection adjustment reaches the best among other antenna types and working distances.When the working distance is the same,the average temperature of the irradiation surface and the area of the high-temperature area under the action of the two antennas(right-angled and equal-angled horn antenna)are basically the same and decrease with the increase of working distance.The optimal microwave parameters are:a right-angle horn antenna with a working distance of 5 cm.Subsequently,in further experiments,the optimal parameters were used to irradiate for 20 s and 40 s at a microwave power of 60 kW,respectively.The surface damage extended 38 cm×30 cm and 53 cm×30 cm,respectively,and the damage extended to a depth of about 50 cm.The drilling speed was increased by 56.2%and 66.5%,respectively,compared to the case when microwaves were not used.