Coronary microembolization induced myocardial contractile dysfunction through a p38 mapk pathway

Background Cathepsin S and its endogenous inhibitor cystatin C are implicated in the pathogenesis of atherosclerosis,especially in the plaque destabilization and rupture leading to acute coronary syndrome.However, whether circulating cathepsin S and cystatin C also change in association with coronary plaque morphology is unknown yet. Methods Sprague-Dawley rats were randomly divided into three groups;Sham group,CME group and SB203580 group (n=10 per group).CME rats were produced by injection of 42μm microspheres into the left ventricle with occlusion of the ascending aorta.SB203580,a p38 MAPK inhibitor,was injected into femoral vein after finishing the injection of microspheres in SB203580 group.Left ventricular Ejection Fraction was determined by echocardiography.The level of phosphorylated and total P38 MAPK in myocardium was assessed by Western Blot.Results Left ventricular(LV) Ejection Fraction was depressed at 3 hours and until up to 12 hours in CME group.The increased p38 MAPK activation was observed in CME group.The administration of SB203580 partly inhibited the p38 MAPK activity and preserved cardiac contractile function.Conclusions p38 MAPK is significantly activated by CME and the inhibition of p38 MAPK can partly preserve cardiac contractile function.

Realgar transforming solution is involved of JNK, P38 MAPK pathway in down-regulating Ras/MAPK pathway in Caenorhabditis elegans

OBJECTIVE To investigate the effect and the mechanisms of realgar transforming solution(RTS)on down-regulating over activated ras.METHODS we used the optimizing technical processes to obtain the RTS,and eval⁃uate the mechanisms of RTS on down-regulating overactivated ras in Caenorhabditis elegans.RESULTS We found that the mRNA level of let60 and lin45 significantly decreased following exposure to RTS,but mRNA levels of mpk1 were not statistically significant in let60/ras(gf)mutant.RTS together with sorafenib(RAF inhibitors)significantly enhanced the activity of RTS on down-regulating overactivated ras more than RTS only,but 50μmol·L^-1 PD98059,a specific ERK inhibitor did not.Lin45 gene RNAi decreased the ability of RTS on down-regulating overactivated ras significantly,but mpk1 gene RNAi did not,indicating that the activity of RTS on down-regulating overactivated ras mainly through targeting to lin45/raf.In addition,RTS significantly increased mRNA level of pmk1/p38 and jnk1/jnk in let-60/ras(gf)mutant,50μmol·L^-1 SB203580(p38 inhibitor)and SP600125(JNK inhibitor)significantly attenuated the effects of RTS on down-regulating overactivated ras in some degree,and pmk1,jnk1 gene RNAi displayed the similar results,suggesting that P38 and JNK/MAPK pathways in some degree were involved in the effects of RTS on down-regulating overactivated ras in C.ele⁃gans.CONCLUSION Realgar transforming solution down-regulate the Ras/MAPK pathway through JNK and P38 MAPK pathways.

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.

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.

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.

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.

α1-antitrypsin combined with bone marrow mesenchymal stem cells regulates retinopathy in diabetic rats via p38 MAPK/NF-κB signaling pathway

Objective:To investigate the effect ofα1-antitrypsin combined with bone marrow mesenchymal stem cells on retinopathy in diabetic rats and its mechanism.Methods:A model of diabetic retinopathy was established by intraperitoneal injection of streptozotocin.The 30 Wistar rats successfully modeled were randomly divided into a model group,a bone marrow mesenchymal stem cell group and a combined group(α1-antitrypsin combined with bone marrow Mesenchymal stem cells),the blood glucose and serum insulin levels of diabetic rats were measured 4 weeks after treatment.Enzyme-linked immunosorbent assay(ELISA)for measuring serum inflammatory factors IL-1β,IL-6 and TNF-α in rats.Observing the pathological morphology of rat retina under hematoxylin-eosin staining(HE).TUNEL staining to observe the apoptosis of rat retinal nerve cells.Immunohistochemical method to detect the expression level of CD45 in retinal tissue.Real-time fluorescence quantitative PCR was used to detect the expression of retinal vascular endothelial growth factor(VEGF),hypoxiainducible factor-1α(HIF-1α),and angiotensinⅡ(ANGⅡ)mRNA.Western blot was used to detect the expression of p38 MAPK/NF-κB signaling pathway-related proteins in the retinal tissue of each group of rats.Results:Compared with the control group,the rats in the model group had increased blood glucose,decreased insulin levels,increased serum IL-1β,IL-6,and TNF-α levels,and had obvious lesions in the retina.CD45 showed high expression in retinal tissue,VEGF,HIF-1α,ANGⅡ mRNA expression increased,p-p38,p-p65,p-IκBα protein expression increased(P<0.05).Compared with the model group,the bone marrow mesenchymal stem cell group and the combined group have decreased blood glucose,increased insulin levels,and decreased serum IL-1β,IL-6 and TNF-α levels.Retinopathy is improved,apoptosis of retinal nerve cells is reduced,CD45 expression in retinal tissue is reduced,VEGF,HIF-1α,ANGⅡ mRNA expression is decreased,and p-p38,p-p65,p-IκBα protein expression is decreased.Compared with the bone marrow mesenchymal stem cell group,the effect of the combined group was more obvious(P<0.05).Conclusion:α1-antitrypsin combined with bone marrow mesenchymal stem cell transplantation can improve the degree of retinopathy in diabetic rats.The mechanism may be related to the inhibition of p38 MAPK/NF-κB signaling pathway.

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.

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.

Safflower polysaccharide inhibits hepatocellular carcinoma cells through P38MAPK activation

Background:Safflower is a traditional medicine that is widely used to treat various diseases.Safflower polysaccharide is one of the effective constituents of safflower.This study explored the anti-tumor effect of safflower polysaccharide and its possible mechanism.Methods:The MTT assay was used to detect the proliferation of hepatocellular carcinoma cells(SMMC-7721 cells).We observed cell apoptosis with a fluorescence microscope.And we used qRT-PCR and western blot to detect the expression of cell cycle related factors.Results:Safflower polysaccharide could inhibit the growth of SMMC-7721 cells in a dose-dependent manner and induce its apoptosis.Compared with the blank group,the cell proliferation-related protein of CDC25B and Survivin were down-regulated in SMMC-7721 cells treated with safflower polysaccharide,while the cell apoptosis-related protein levels of P53 and P38MAPK were up-regulated(P<0.05).In addition,safflower polysaccharide inhibited the protein levels of CDC2(P<0.05).Conclusion:Safflower polysaccharide can inhibit the growth of hepatocellular carcinoma cells by inhibiting proliferation and promoting apoptosis,and the P38MAPK pathway may play an important role in this process.

Loss of GRB2 associated binding protein 1 in arteriosclerosis obliterans promotes host autophagy

Background:Arteriosclerosis obliterans(ASO)is a major cause of adult limb loss worldwide.Autophagy of vascular endothelial cell(VEC)contributes to the ASO progression.However,the molecular mechanism that controls VEC autophagy remains unclear.In this study,we aimed to explore the role of the GRB2 associated binding protein 1(GAB1)in regulating VEC autophagy.Methods:In vivo and in vitro studies were applied to determine the loss of adapt protein GAB1 in association with ASO progression.Histological GAB1 expression was measured in sclerotic vascular intima and normal vascular intima.Gain-and loss-of-function of GAB1 were applied in VEC to determine the effect and potential downstream signaling of GAB1.Results:The autophagy repressor p62 was significantly downregulated in ASO intima as compared to that in healthy donor(0.80 vs.0.20,t=6.43,P<0.05).The expression level of GAB1 mRNA(1.00 vs.0.24,t=7.41,P<0.05)and protein(0.72 vs.0.21,t=5.97,P<0.05)was significantly decreased in ASO group as compared with the control group.Loss of GAB1 led to a remarkable decrease in LC3II(1.19 vs.0.68,t=5.99,P<0.05),whereas overexpression of GAB1 significantly led to a decrease in LC3II level(0.41 vs.0.93,t=7.12,P<0.05).Phosphorylation levels of JNK and p38 were significantly associated with gain-and loss-of-function of GAB1 protein.Conclusion:Loss of GAB1 promotes VEC autophagy which is associated with ASO.GAB1 and its downstream signaling might be potential therapeutic targets for ASO treatment.

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.

Guaiane-type Sesquiterpenoid Dimers from Artemisia zhongdianensis and Antihepatoma Carcinoma Activity via the p38MAPK Pathway

17 new guaiane-type sesquiterpenoid dimers(GSDs),artemzhongdianolides B1—B17(1—17),were isolated from Artemisia zhongdianensis under the guidance of bioassay,and elucidated by spectral analyses(HRESIMS,1D and 2D NMR,IR,ECD).The absolute configuration of compounds 1,3,7,9,10,and 13 was determined by single-crystal X-ray diffraction analyses.Structurally,artemzhongdianolides B1(1)and B2(2)were the first example of the GSDs fused via a C-13/C-13'single bond,and artemzhongdianolides B3—B17 were[4+2]Diels–Alder adducts of two monomeric guaianolides.Most of the compounds showed antihepatoma cytotoxicity with IC_(50) values ranging from 9.9 to 170.1μmol/L.Importantly,artemzhongdianolide B9(9)was the most active one against three hepatoma cell lines with IC_(50) values of 13.1μmol/L(HepG2),19.5μmol/L(Huh7),and 19.5μmol/L(SK-Hep-1),and dose-dependently inhibited cell migration and invasion,induced G1 cell cycle arrest and cell apoptosis in HepG2 cells.Compound 9 might suppress HepG2 cells via affecting the p38MAPK signaling pathway suggested by machine learning approach,and significantly upregulated expression of phosphorylated p38 validated by Western blot assay.

Targeting of p38 Mitogen-activated Protein Kinases to Early Growth Response gene 1 (EGR-1) in the Human Paclitaxel-resistance Ovarian Carcinoma Cells

To investigate the relationship between the expression of early growth response gene 1 （EGR-1） and p38MAPK pathway in the paclitaxel resistance of ovarian carcinoma cells, the effect of p38MAPK inhibitor SB203580 on cell apoptosis was examined by using Hoechst 33258 staining. The intracellular Rh123 （Rhodamine 123） accumulation was detected by the flow cytometry （FCM）. The 50% inhibition concentration （IC50） of paclitaxel for A2780/Taxol cells was determined by MTT method. Electrophoretic motility shift assay （EMSA） was employed to examine the EGR-1DNA binding activity. MDR1 and EGR-1 mRNA were assessed by RT-PCR. The expressed of p-gp, phos- phorylated p53 and p38 were detected by Western blotting. SB203580 could remarkably promote the apoptosis of A2780/Taxol cells, and the cell apoptosis was in a time-dependent manner. Cellular Rh123 accumulation was increased, and the IC50 of paclitaxel for A2780/Taxol cells was decreased significantly. A2780/Taxol cell line after SB203580 treatment was shown to have a significantly higher level of EGR-1 DNA binding activity. SB203580 down-regulated the activity of p38MAPK pathway, but up-regulated EGR-1 expression. SB203580 significantly increased the level of cellular phosphorylated p53 protein, but decreased the p-gp protein level and MDR1 mRNA level in A2780/Taxol cells. There existed a close relationship between p38MAPK pathway and the paclitaxel resistance of ovarian carcinoma cells. The expression of EGR-1 mediated by p38MAPK pathway plays a critical role in paclitaxel resistance of ovarian carcinoma cells.

Magnesium lithospermate B inhibits lipopolysaccharide-induced endothelial activation through NF-KB pathway

Aim Magnesium lithospermate B （MLB） is the most abundant hydrophilic active component of Salvia rniltiorrhiza Radix, a traditional Chinese herbal medicine mainly used to treat cardiovascular diseases. Studies have shown that endothelial activation contributes to the pathophysiology of cardiovascular diseases such as atherosclero- sis, diabetic vasculopathy, heart failure and hypertension. In the present study, the effects of MLB on endothelial activation were investigated. Lipopolysaccharide （LPS） 1 mg L^-1 was employed to induce endothelial activation, which was determined by relative gene expression and endothelial adhesion assay. Results showed that pretreatment with MLB attenuated LPS-induced ICAM1, VCAM1 and TNF-α upregulation in human dermal microvascular endo- thelial cells （HMEC-1） in dose-dependent manner, which contributed to the reduction of THP-1 adhesion to HMEC-1. Furthermore, it was revealed that 100 μmol · L^-1 MLB significantly decreased the nuclear translocation of NF-KB p65, a critical transcription factor in LPS-indueed inflammatory response, through the inhibition of IKBμ degradation. Besides, the transcriptional activity of NF-KB p65 was also inhibited by the pretreatment of MLB. Mo- reover, MLB pretreatment considerably inhibited LPS-induced p38 phosphorylation, which at least partly contribu- ted to the reduction of ICAM1 expression. In conclusion, these findings suggest that MLB inhibits LPS-induced nu- clear translocation and transcripitional activity of NF-KB, thus attenuates the increased expression of adhesion mole- cules and inflammatory factors, protects endothelial cells from LPS-induced activation.

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.

Protective Effects of Sapindus Saponins in Spontaneously Hypertensive Rats

Objectives： To investigate the protective effects of Sapindus saponins in spontaneously hypertensive rats, and the possible cellular and molecular mechanisms. Methods： Thirty-two 16-week-old spontaneously hypertensive rats were randomly divided into four groups （8 in each group）： model group （placebo）, positive control group （27 mg/kg of Captopril Tablets）, Sapindus saponins groups （27 mg/kg and 108 mg/kg, respectively）. Another 8 healthy Wistar-Kyoto strain （WKY） rats were used as the normal group. The animals were treated for 8 weeks. Blood pressure of rats was determined by non-invasive blood pressure meter （BP-6）. Furthermore, the contents of angiotensin Ⅱ （Ang Ⅱ） in plasma and myocardial tissue were determined by enzyme-linked immunosorbent assay （ELISA）, the gene expression of receptor angiotensin type 1 （AT1R） in aorta was determined by quantitative real- time polymerase chain reaction （qRT-PCR）. The protein expression of transforming growth factor- β1 （TGF- 1β1） and AT1R in heart was determined by immunohistochemical staining. The protein expression of p-phosphorylation of p38 mitogen-activated protein kinase （p-p38MAPK） was determined by Western blotting. The contents of interleukin （IL）-1, IL-6 and tumor necrosis factor （TNF） in serum were determined by radioimmunoassay. And the histopathological and morphological changes of aorta and heart tissue samples were assessed semi-quantitatively by hematoxylin-eosin （HE） or Masson staining. Results： Thirty minutes after single or continuous treatment, systolic blood pressure （SBP） was reduced significantly in Sapindus saponins groups. And the contents of Ang 11, IL-1, IL-6 and TNF-α in serum, the expression of AT1R mRNA, p-p38MAPK and TGF- β1 were significantly suppressed dose-dependently （P〈0.05 or 1=〈0.01）. With the Sapindus saponins treatment, compared with those of the model group, the cardiac and aortic pathological changes were ameliorated significantly. Conclusions： Our findings suggest that Sapindus saponins might have protective effects in spontaneously hypertensive rats, the cellular and molecular mechanisms of which might be relevant to the regulation of inflammatory responses mediated by p-p38MAPK signal pathway based on activated Ang Ⅱ and AT1R.

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.