Investigation on the mechanism of Qiangxinhuoli prescription in the treatment of chronic heart failure based on p38-MAPK signaling pathway

Background:The aim of this study is to investigate the mechanism of action underlying the therapeutic effects of the national patent Chinese medicine compound“Qiangxinhuoli prescription(QXHLF)”on chronic heart failure(CHF).Methods:In vitro,the H_(9)C_(2) cell model was induced by ANGII,and cell proliferation and related protein expression were detected by Cell Counting Kit-8 and Western blot.In vivo,A rat model of CHF was prepared by ligation of the left anterior descending coronary artery.The effects of QXHLF on cardiac function in CHF rats were evaluated by cardiac index,hemodynamic changes,enzyme-linked immunosorbent assay,hematoxylin-eosin staining,immunohistochemistry,Western blot and RT-PCR.The expression of pro-apoptotic factors and anti-apoptotic factors,as well as TGFβ1,p-p38,TAK 1 mRNA,and protein,were detected.Results:In vitro,QXHLF has a significant inhibitory effect on the proliferation of H_(9)C_(2) cells.QXHLF can reduce the expression levels of TAK 1,TGFβ1,p-p38,Caspase3 and BAX proteins in H_(9)C_(2) cells,and increase the expression level of BCL_(2) protein.In vivo,QXHLF has the potential to increase left ventricular systolic pressure,m aximum rate of change in left ventricular pressure while decreasing left ventricular end diastolic pressure,and inhibiting the serum levels of brain natriuretic peptide.Moreover,QXHLF exhibits significant improvements in the pathological alterations of myocardial cells and fibers in CHF rats,leading to enhanced myocardial tissue morphology and notable advantages in combating myocardial fibrosis.QXHLF can reduce the levels of BAX and Caspase3 and up-regulate the expression of BCL_(2),thereby inhibiting cardiomyocyte apoptosis.Furthermore,QXHLF demonstrates inhibitory effects on the mRNA and protein expression levels of TGFβ_(1),TAK_(1),and p-p38 in the heart tissue of the CHF rat model.Conclusion:These findings indicate that QXHLF has a therapeutic effect on CHF by inhibiting the p38-MAPK signaling pathway,reducing myocardial fibrosis,preventing apoptosis,inhibiting cell proliferation,and restoring myocardial injury.

To investigate the effects of butylphthalide on reducing neuronal apoptosis in rats with cerebral infarction by inhibiting the JNK/P38 MAPK signaling pathway

Objective:To investigate the effects of butylphthalide on reducing neuronal apoptosis in rats with cerebral infarction by inhibiting the JNK/P38 MAPK signaling pathway.Methods:Forty-eight SD male rats were divided into DZ group(control group),CI group(model group)and NBP group(butylphthalide group).Rats in CI group and NBP group were used to establish cerebral infarction models.NBP group used NBP.The solution(80 mg/(kg?d))was administered orally,and the remaining two groups were administered with the same volume of peanut oil.After 14 consecutive days of treatment,the Zea Longa score was used to evaluate the neurological function of DZ,CI and NBP rats.Scoring,TTC staining was used to observe the cerebral infarction volume of rats in DZ group,CI group and NBP group,HE staining was used to observe the pathological morphology of brain tissue in DZ group,CI group and NBP group.Neuronal apoptosis,Western blot was used to detect the expression of p-JNK and p-p38MAPK in brain tissues of DZ group,CI group and NBP group.Results:The neurological function of the rats in the CI group was higher than that in the DZ group,and the difference was statistically significant(P<0.05).The neurological function score of the rats in the NBP group was reduced compared with the CI group,and the difference was statistically significant(P<0.05).The cerebral infarction volume in the group was 35.56%higher than that in the DZ group,and the difference was statistically significant(P<0.05).The minor infarct volume in the NBP group was 21.59%,which was less than that in the CI group,and the difference was statistically significant(P<0.05).Nerve cells are neatly sorted,with a large number.The gap between blood vessels and interstitial tissue in the CI group is enlarged,the cells are severely contracted,and the neuron structure is incomplete.Compared with the CI group,the NBP group has reduced neuron contraction and increased number;The dead nerve cells were brown.The apoptosis rate of nerve cells in the CI group was 79.65%higher than that in the DZ group was 5.82%.The difference was statistically significant(P<0.05).The nerve cell apoptosis rate in the NBP group was 30.23%.Compared with CI group,the difference was statistically significant(P<0.05);Western blot results showed that p-JNK and p-p38MAPK protein expression in CI group was higher than that in DZ group,and the difference was statistically significant(P<0.05).The levels of p-JNK and p-p38MAPK proteins in the NBP group were lower than those in the CI group.There was statistically significant(P<0.05).Conclusion:Butylphthalide can improve neurological damage,reduce apoptotic nerve cells,and reduce infarct volume in rats with cerebral infarction,which is related to the inhibition of JNK/P38 MAPK pathway expression.

p38/ATF-2通路参与C反应蛋白诱导的内皮细胞活化

目的：考察p38 MAPK／ATF-2通路在C反应蛋白（ CRP）诱导的内皮细胞活化中的作用。方法：采用培养的人冠状动脉内皮细胞（ HCAEC）第3～7代用于实验。 CRP刺激诱导内皮细胞活化，给予p38抑制剂SB203580和SB202190干预。免疫印迹法检测p-eNOS、p-p38和p-ATF2的水平；ELISA法测定HCAEC分泌的黏附分子ICAM-1、VCAM-1和MCP-1的变化。结果： CRP呈浓度依赖性地抑制p-eNOS水平， CRP诱导HCAEC分泌ICAM-1、VCAM-1和MCP-1；CRP激活p38／ATF-2通路；SB203580和SB202190部分恢复p-eNOS水平和抑制CRP诱导的ICAM-1、VCAM-1和MCP-1分泌。结论：p38 MAPK／ATF-2通路参与CRP诱导的HCAEC活化。

Betulinic acid protects against ovarian impairment by decreasing F-2 toxin-induced oxidative stress and inflammation associated with the downregulation of p38 expression in mice

F-2 toxin is an estrogenic mycotoxin that causes reproductive disorders in animals.Betulinic acid(BA)is a natural pentacyclic lupane-structure triterpenoid that has diverse pharmacological activities.In this study,the antioxidative and anti-inflammatory effects of BA and its underlying mechanism are explored in F-2 toxin-triggered mouse ovarian damage.We found that BA alleviated the F-2 toxin-induced ovarian impairment by stimulating follicle growth,reducing inflammatory cell infiltration,repairing damaged mitochondria and endoplasmic reticulum.Simultaneously,BA not only reversed F-2 toxin-induced reduction of follicle stimulating hormone(FSH)and luteinizing hormone(LH)levels in the serum,but also restrained the protein expression of the estrogen receptors a(ERa)and ERβ.Moreover,BA restored the balance of F-2 toxin-induced ovarian redox system disorders.Subsequently,we found that 0.25 mg/kg BA played an anti-inflammatory role in the F-2 toxin-induced ovarian impairment by decreasing interleukin-1β(IL-1β).IL-6,and tumor necrosis factor-α(TNF-α)mRNA expression,as well as inhibiting p38 protein expression.These data demonstrated that BA exerts its protective effect on F-2 toxin-induced ovarian oxidative impairment and inflammation by inhibiting p38 expression,which implies a natural product-based medicine to ameliorate F-2 toxin-caused female reproductive toxicity and provides a detoxifying method for food contaminated by mycotoxin.

Promotion effect of FOXCUT as a microRNA sponge for miR-24-3p on progression in triple-negative breast cancer through the p38 MAPK signaling pathway

Background:Triple-negative breast cancer(TNBC)is a type of highly invasive breast cancer with a poor prognosis.According to new research,long noncoding RNAs(lncRNAs)play a significant role in the progression of cancer.Although the role of lncRNAs in breast cancer has been well reported,few studies have focused on TNBC.This study aimed to explore the biological function and clinical significance of forkhead box C1 promoter upstream transcript(FOXCUT)in triple-negative breast cancer.Methods:Based on a bioinformatic analysis of the cancer genome atlas(TCGA)database,we detected that the lncRNA FOXCUT was overexpressed in TNBC tissues,which was further validated in an external cohort of tissues from the General Surgery Department of the First Affiliated Hospital of Nanjing Medical University.The functions of FOXCUT in proliferation,migration,and invasion were detected in vitro or in vivo.Luciferase assays and RNA immunoprecipitation(RIP)were performed to reveal that FOXCUT acted as a competitive endogenous RNA(ceRNA)for the microRNA miR-24-3p and consequently inhibited the degradation of p38.Results:lncRNA FOXCUT was markedly highly expressed in breast cancer,which was associated with poor prognosis in some cases.Knockdown of FOXCUT significantly inhibited cancer growth and metastasis in vitro or in vivo.Mechanistically,FOXCUT competitively bounded to miR-24-3p to prevent the degradation of p38,which might act as an oncogene in breast cancer.Conclusion:Collectively,this research revealed a novel FOXCUT/miR-24-3p/p38 axis that affected breast cancer progression and suggested that the lncRNA FOXCUT could be a diagnostic marker and therapeutic target for breast cancer.

幽门螺杆菌对人胃癌MKN45细胞p38MAPK信号转导通路激活作用的研究

背景与目的:环氧合酶2(cyclooxygenase-2,COX-2)是花生四烯酸转化为前列腺素(prostaglandins,PGs)代谢中重要的限速酶,幽门螺杆菌(Helicobacter pylori,Hp)感染诱导胃黏膜COX-2的过度表达是胃癌发生的重要环节,但坳感染胃黏膜细胞COX-2表达的机制尚不清楚。本研究旨在揭示Hp对人胃癌MKN45细胞COX-2表达和p38MAPK信号通路的影响,探讨COX-2表达的可能机制。方法:采用实时荧光定量PCR (real time-PCR)检测Hp标准株NCTC11637感染对人胃癌MKN45细胞COX-2 mRNA转录的影响,Western blot检测Hp COX-2蛋白表达的影响和p38MAPK信号通路的激活及其下游因子ATF-2的表达。结果:Hp感染人胃癌MKN45细胞后,COX-2 mRNA的表达明显上调,Hp感染3、6、9、12 h后COX-2 mRNA的表达量分别为正常值的3倍、7.2倍、5.1倍和4.3倍,各时间组COX-2 mRNA表达均明显高于对照组(P<0.01);Hp与MKN45细胞共培养24 h后,COX-2蛋白的表达亦显著增加(P<0.01)。Hp感染MKN45 20 min后,p38MAPK信号通路被激活,60 min达峰值:p38MAPK下游因子ATF-2的表达也明显增加,2 h达高峰,随着作用时间的延长,表达逐渐下降,24 h仍有表达。结论:np感染能诱导人胃癌MKN45细胞COX-2的表达;激活p38MAPK信号通路,增加其下游因子ATF-2的表达,可能是其诱导COX-2表达的机制。

ANTI-OXIDATIVE MECHANISMS OF PRAVASTATIN PREVENTING AORTIC ATHEROSCLEROSIS IN apoE KNOCKOUT MICE:ROLE OF p38 MAPK PATHWAY

Objective To determine whether pravastatin exerts anti-oxidative effects on preventing aortic＂ atherosclerosis via modulating p38 MAPK pathway. Methods Male 8-week-old apoE^-/- mice fed a diet containing 1.25% cholesterol （wt/wt） were divided into pravastatin group administered with pravastatin （80 mg. kg ^-1· d^-1 ） and atherosclerosis group administered with PBS; and male 8-week-old C57BL/6J mice fed a normal diet were as control group （ n = 12 ）. In thoracoabdominal aortas of mice, levels of Malondialdehyde （ MDA ） and activities of superoxide dismutase （ SOD ） were measured and expression of phosphorylated p38 MAPK （ p-p38 MAPK） and phosphorylated signal transducer and activator of transcr（ption 1 （pSTAT1） were examined by Western blotting. Results After eight weeks, atherosclerosis in aortic root was significantly prevented by pravastatin. In aortic atherosclerosis lesion, the level of MDA was significantly reduced; adversely the activity, of SOD was increased. Expressions of p-p38 MAPK and pSTAT1 were significantly decreased in aortic atherosclerosis lesion. Conclusion Our results suggests that anti-oxidative mechanisms of pravastatin preventing aortic atherosclerosis may partially depend on modulating p38 MAPK signal pathway.

苓桂术甘汤治疗膜迷路积水豚鼠P38MAPK信号通路实验研究

目的探索P38MAPK信号通路与苓桂术甘汤治疗膜迷路积水豚鼠的关联性。方法随机将36只健康红目豚鼠随机分为空白组、模型组、苓桂组及苓桂加α-LA组,每组各9只豚鼠(18耳),除空白组外,其余3组采用腹腔注射醋酸去氨加压素方法造模,6μg·kg^-1·d^-1,连续注射10 d。造模成功后,苓桂组豚鼠每日予苓桂术甘汤2.79 g/kg灌胃,苓桂加α-LA组每日予2.79 g/kg及α-LA 46.5 mg/kg同时灌胃,空白组及模型组以1 mL生理盐水灌胃。各组正常饲养,7 d后取材。采用HE染色法观察各组豚鼠耳蜗积水情况,免疫组化、荧光定量PCR方法以及Western-Blot法观察P38MAPK、p-P38MAPK、ATF-2蛋白在各组豚鼠耳蜗的表达情况。选用SPSS19.0软件统计分析各实验结果,探讨P38MAPK信号通路与苓桂术甘汤治疗梅尼埃病的关联性。结果蜗管面积与耳蜗总面积比值:模型组、苓桂组、苓桂加α-LA组与空白组比较均增加(P<0.01);苓桂组与模型组比较减小(P<0.01);苓桂加α-LA组与模型组比较差异无统计学意义(P>0.05);苓桂加α-LA组比苓桂组增加(P<0.01)。免疫组化方法观察P38MAPK、p-P38MAPK、ATF-2蛋白在豚鼠耳蜗表达情况:与空白组比较,模型组、苓桂组、苓桂+α-LA组P38MAPK、p-P38MAPK、ATF-2蛋白表达均下调(P<0.01);与模型组比较,苓桂组P38MAPK、p-P38MAPK、ATF-2蛋白以及苓桂+α-LA组p-P38MAPK蛋白表达水平上调(P<0.01);与苓桂组比较,苓桂+α-LA组P38MAPK、p-P38MAPK、ATF-2蛋白表达均下调(P<0.01)。荧光定量PCR方法观察P38MAPK mRNA/p-P38MAPK mRNA、ATF-2 mRNA在豚鼠耳蜗表达情况:与空白组比较,模型组、苓桂组P38MAPK mRNA/p-P38MAPK mRNA、ATF-2 mRNA表达水平下调(P<0.01),苓桂+α-LA组ATF-2 mRNA表达水平下调(P<0.01);与模型组比较,苓桂组、苓桂+α-LA组P38MAPK mRNA/p-P38MAPK mRNA、苓桂组ATF-2 mRNA表达水平上调(P<0.01);与苓桂组比较,苓桂+α-LA组P38MAPK mRNA/p-P38MAPK mRNA、ATF-2 mRNA表达下调(P<0.01)。Western-Blot方法观察P38MAPK、p-P38MAPK、ATF-2蛋白在耳蜗表达情况:与空白组比较,模型组、苓桂组、苓桂+α-LA组P38MAPK、p-P38MAPK、ATF-2蛋白表达均下调(P<0.01);与模型组比较,苓桂组、苓桂+α-LA组P38MAPK、p-P38MAPK、ATF-2蛋白表达水平上调(P<0.01);与苓桂组比较,苓桂+α-LA组P38MAPK、p-P38MAPK、ATF-2蛋白表达均下调(P<0.01)。结论苓桂术甘汤可在一定程度上减轻豚鼠膜迷路积水。苓桂术甘汤治疗梅尼埃病可能是通过P38MAPK信号通路实现的。α-LA可能抑制P38MAPK通路的活性,进而减少氧化应激反应的发生。

Polysaccharides from Agrocybe cylindracea residue alleviate type 2-diabetes-induced liver and colon injuries by p38 MAPK signaling pathway

In this experiment,we investigated the possible mechanism of polysaccharides from Agrocybe cylindracea residue (PACR) on ameliorating the type-2-diabetes-induced liver and colon injuries.Animal experiments have proved that PACR could reduce the oxidative damage and inflammatory response.Meanwhile,the PACR could restore lipid levels,decrease the level of liver and colon lesions in injured mice,and finally play a role in protecting liver and colon.The results showed that PACR could be used as a supplement to decrease blood glucose and relieve T2DM and reduce oxidative stress and inflammatory response by inhibiting the activation of p38 MAPK signaling pathway.

Mannitol inhibits the proliferation of neural stem cell by a p38 mitogen-activated protein kinase-dependent signaling pathway

Purpose:Mannitol is one of the first-line drugs for reducing cerebral edema through increasing the extracellular osmotic pressure.However,long-term administration of mannitol in the treatment of cerebral edema triggers damage to neurons and astrocytes.Given that neural stem cell(NSC)is a subpopulation of main regenerative cells in the central nervous system after injury,the effect of mannitol on NSC is still elusive.The present study aims to elucidate the role of mannitol in NSC proliferation.Methods:C57 mice were derived from the animal house of Zunyi Medical University.A total of 15 pregnant mice were employed for the purpose of isolating NSCs in this investigation.Initially,mouse primary NSCs were isolated from the embryonic cortex of mice and subsequently identified through immunofluorescence staining.In order to investigate the impact of mannitol on NSC proliferation,both cell counting kit-8 assays and neurospheres formation assays were conducted.Thein vitro effects of mannitol were examined at various doses and time points.In order to elucidate the role of Aquaporin 4(AQP4)in the suppressive effect of mannitol on NSC proliferation,various assays including reverse transcription polymerase chain reaction,western blotting,and immunocytochemistry were conducted on control and mannitol-treated groups.Additionally,the phosphorylated p38(p-p38)was examined to explore the potential mechanism underlying the inhibitory effect of mannitol on NSC proliferation.Finally,to further confirm the involvement of the p38 mitogen-activated protein kinase-dependent(MAPK)signaling pathway in the observed inhibition of NSC proliferation by mannitol,SB203580 was employed.All data were analyzed using SPSS 20.0 software(SPSS,Inc.,Chicago,IL).The statistical analysis among multiple comparisons was performed using one-way analysis of variance(ANOVA),followed by Turkey’’s post hoc test in case of the data following a normal distribution using a Shapiro-Wilk normality test.Comparisons between 2 groups were determined using Student’s t-test,if the data exhibited a normal distribution using a Shapiro-Wilk normality test.Meanwhile,data were shown as median and interquartile range and analyzed using the Mann-WhitneyU test,if the data failed the normality test.A p<0.05 was considered as significant difference.Results:Primary NSC were isolated from the mice,and the characteristics were identified using immunostaining analysis.Thereafter,the results indicated that mannitol held the capability of inhibiting NSC proliferation in a dose-dependent and time-dependent manner using cell counting kit-8,neurospheres formation,and immunostaining of Nestin and Ki67 assays.During the process of mannitol suppressing NSC proliferation,the expression of AQP4 mRNA and protein was downregulated,while the gene expression of p-p38 was elevated by reverse transcription polymerase chain reaction,immunostaining,and western blotting assays.Subsequently,the administration of SB203580,one of the p38 MAPK signaling pathway inhibitors,partially abrogated this inhibitory effect resulting from mannitol,supporting the fact that the p38 MAPK signaling pathway participated in curbing NSC proliferation induced by mannitol.Conclusions:Mannitol inhibits NSC proliferation through downregulating AQP4,while upregulating the expression of p-p38 MAPK.

Galectin-9 Promotes Human Trophoblast Cell Invasion through Matrix Metalloproteinase-2 and p38 Signaling Pathway

Objective:Adequate extravillous trophoblast(EVT)invasion plays a crucial role in the establishment of successful pregnancy.Insufficient trophoblast migration and invasion can result in defective placentation,which is associated with a number of clinical pathological conditions of pregnancy including spontaneous abortion and preeclampsia.Galectin-9(Gal-9)has a wide variety of regulatory functions in innate and adaptive immunity during infection,tumor growth,and organ transplantation.Methods:We utilized immortalized human first-trimester EVT cells(HTR8/SVneo)for our functional study.We examined the effects of Gal-9 on viability,proliferation,and invasion of HTR8/SVneo cells,as well as on matrix metalloproteinase-2(MMP-2)production in HTR8/SVneo cells.Furthermore,we observed the effects of different MAPK-signaling pathway inhibitors on the stimulatory functions of Gal-9 on HTR8/SVneo cells’invasion.Results:We verified the secretion of Gal-9 by trophoblasts and detected a correlation between low levels of Gal-9 and spontaneous abortion.Gal-9 promoted the invasion of HTR8/SVneo cells through its interaction with Tim-3,not CD44,and subsequently increased MMP-2 production.Blockade of p38 signaling pathway inhibited Gal-9 activities in HTR8/SVneo cells.Conclusion:Gal-9 promotes human trophoblast cell invasion through MMP-2 and p38 signaling pathway in a Tim-3-dependent manner.

The p38/MAPK pathway as a therapeutic target to prevent therapeutic escape of breast cancer stem cells

Cancer stem cells(CSCs)play an important role in metastasis development,tumor recurrence,and treatment resistance,and are essential for the eradication of cancer.Currently,therapies fail to eradicate CSCs due to their therapeutic stress-induced cellular escape,which leads to enhanced aggressive behaviors compared with CSCs that have never been treated.However,the underlying mechanisms regulating the therapeutic escape remain unknown.To this end,we established a model to isolate the therapeutic escaped CSCs(TSCSCs)from breast CSCs and performed the transcription profile to reveal the mechanism.Mechanistically,we demonstrated that the behavior of therapeutic escape was regulated through the p38/MAPK signaling pathway,resulting in TSCSCs exhibiting enhanced motility and metastasis.Notably,blocking the p38/MAPK signaling pathway effectively reduced motility and metastasis ability both in vitro and in vivo,which were further supported by downregulated motility-related genes and epithelial-mesenchymal transition(EMT)-related proteins vimentin and N-cadherin.The obtained findings reveal the p38/MAPK pathway as a potential therapeutic target for TSCSCs and would provide profound implications for cancer therapy.

疏风宣肺汤对慢性支气管炎大鼠p38MAPK/ATF-2信号转导通路的影响

目的:探讨疏风宣肺汤对慢性支气管炎大鼠p38MAPK/ATF-2信号转导通路的作用。方法:将SD大鼠随机分为空白对照组、模型组、疏风宣肺汤组、宣肺止嗽合剂组,采用混合烟雾吸入法建立慢性支气管炎大鼠模型,分别给予相应药物进行干预。检测各组大鼠p38MAPK蛋白表达含量、肺泡巨噬细胞计数、ATF-2蛋白表达含量。结果:疏风宣肺汤组能够明显降低p38MAPK蛋白表达含量、肺泡巨噬细胞计数及ATF-2蛋白表达含量,其治疗效果优于宣肺止嗽合剂组,差异均有统计学意义(P <0. 05)。结论:疏风宣肺汤可能是通过抑制p38MAPK/ATF-2信号通路表达,发挥对慢性支气管炎的治疗作用。

The EGFR-P38 MAPK axis up-regulates PD-L1 through miR-675-5p and down-regulates HLA-ABC via hexokinase-2 in hepatocellular carcinoma cells

Background:Immunotherapy has been shown to be a promising strategy against human cancers.A better understanding of the immune regulation in hepatocellular carcinoma(HCC)could help the development of immunotherapy against HCC.The epidermal growth factor receptor(EGFR)signaling is frequently activated in HCC and plays important roles in tumorigenesis.However,its role in HCC immunity is still largely unknown.This study aimed to investigate the impact of EGFR signaling on programmed death-ligand 1(PD-L1)and human leukocyte antigen class-I(HLA-I)expression in HCC cells and its underlying mechanisms.Methods:The expression of phosphorylated EGFR(p-EGFR),PD-L1,and HLAI(HLA-ABC)in HCC specimens was detected by immunohistochemistry,and their correlations were analyzed.PD-L1 and HLA-ABC expression in EGFRactivated HCC cells were detected by quantitative real-time PCR,Western blotting,and flow cytometry,and T cell-mediated lysis was performed to test the immunosuppressive effects of PD-L1 and HLA-ABC alterations in HCC cells.Furthermore,the underlying mechanisms of EGFR activation-induced PD-L1 up-regulation and HLA-ABC down-regulation were explored by animal experiments,luciferase reporter assay,and gene gain-and loss-of-function studies.Results:p-EGFR was positively correlated with PD-L1 and negatively correlated with HLA-ABC expression in HCCs.EGFR activation by its ligand EGF up-regulated PD-L1 and down-regulated HLA-ABC in HCC cells,which was functionally important and could be abolished by the EGFR inhibitor,gefitinib,both in vitro and in vivo.Mechanistically,enhanced P38 mitogenactivated protein kinase(MAPK)activation down-regulated microRNA-675-5p(miR-675-5p)and up-regulated glycolysis-related enzyme hexokinase 2(HK2);miR-675-5p down-regulation enhanced the stability of PD-L1 mRNA probably via the 3’-untranslated region(3’-UTR)of PD-L1 and thereby caused PD-L1 accumulation,and HK2 up-regulation enhanced aerobic glycolysis and mediated a decrease in HLA-ABC.Conclusions:The EGFR-P38 MAPK axis could up-regulate PD-L1 through miR-675-5p and down-regulate HLA-ABC via HK2 in HCC cells.Our study reveals a novel signaling network that may cause immune suppression in HCC and suggests that EGFR signaling can be targeted for HCC immunotherapy.

芪术颗粒对肝纤维化形成过程中p38 MAPK信号传导通路的影响

目的:观察芪术颗粒在肝纤维化形成过程中对p38 MAPK信号传导通路的影响。方法:Waster大鼠随机分为正常组、模型组、实验对照组和芪术颗粒组,用四氯化碳复制肝纤维化模型,造模同日即给予相应治疗,分别于造模后的第1、2、4周处理大鼠,取肝组织Western blot免疫印迹法检测总p38 MAPK、p-p38 MAPK、总ATF-2及p-ATF-2蛋白表达。结果:随着肝纤维化的进展,总p38 MAPK、p-p38 MAPK、总ATF-2及p-ATF-2蛋白表达均有上调,而芪术颗粒对其上调均有一定的抑制作用,与模型组比较差异显著(P<0.05)。结论:芪术颗粒对p38 MAPK信号传导通路的激活有调控作用,从而抑制肝纤维化的发生和发展。

The functional analysis of transiently upregulated miR-101 suggests a “braking” regulatory mechanism during myogenesis

Skeletal muscle differentiation is a highly coordinated process that involves many cellular signaling pathways and microRNAs(miRNAs).A group of muscle-specific miRNAs has been reported to promote myogenesis by suppressing key signaling pathways for cell growth.However,the functional role and regulatory mechanism of most non-muscle-specific miRNAs with stage-specific changes during differentiation are largely unclear.Here,we describe the functional characterization of miR-101a/b,a pair of non-muscle-specific miRNAs that show the largest change among a group of transiently upregulated miRNAs during myogenesis in C2C12 cells.The overexpression of miR-101a/b inhibits myoblast differentiation by suppressing the p38/MAPK,Interferon Gamma,and Wnt pathways and enhancing the C/EBP pathway.Mef2a,a key protein in the p38/MAPK pathway,was identified as a direct target of miR-101a/b.Interestingly,we found that the long non-coding RNA(lncRNA)Malat1,which promotes muscle differentiation,interacts with miR-101a/b,and this interaction competes with Mef2a mRNA to relieve the inhibition of the p38/MAPK pathway during myogenesis.These results uncovered a“braking”role in differentiation of transiently upregulated miRNAs and provided new insights into the competing endogenous RNA(ceRNA)regulatory mechanism in myoblast differentiation and myogenesis.