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Background/Aims: Studies have demonstrated that 2-dodecyl-6-methoxycyclohexa-2, 5-diene-1, 4-dione (DMDD), isolated from the roots of Averrhoa carambola L., has significant therapeutic potential for the treatment of diabetes. However, the protective effect of DMDD against pancreatic beta cell dysfunction has never been reported. We investigated whether DMDD protected against palmitic acid-induced dysfunction in pancreatic β-cell line Min6 cells by attenuating the inflammatory response and apoptosis and to shed light on its possible mechanism. Methods: Cell viability was assessed by CCK-8. Glucose-stimulated insulin secretion levels and inflammatory cytokines levels were examined by ELISA. Apoptosis was assessed by Annexin V-FITC/PI Flow cytometry assay, Hoechst 33342/PI double-staining assay, and Transmission electron microscopy assay. Relative quantitative real-time PCR and western blot were used to determine the expressions of genes and proteins. Results: Cell viability and glucose-stimulated insulin secretion levels were increased in DMDD-pretreated Min6 cells. DMDD inhibited inflammatory cytokines IL-6, TNF-α and MCP-1 generations in palmitic acid (PA)-induced Min6 cells. Moreover, DMDD protected against PA-induced Min6 cells apoptosis and the expression of Cleaved-Caspase-3, -8 and -9 were down-regulated and the Bcl-2/Bax ratio was increased in DMDD-pretreated Min6 cells. In addition, the expression of TLR4, MyD88 and NF-κB were down-regulated in DMDD-pretreated Min6 cells and TAK-242-pretreated group cells. Conclusions: DMDD protected Min6 cells against PA-induced dysfunction by attenuating the inflammatory response and apoptosis, and its mechanism of this protection was associated with inhibiting the TLR4-MyD88-NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: Chinese prescription Fufang-Liu-Yue-Qing (FLYQ) has long been employed clinically to treat chronic hepatitis B, and we have reported its beneficial effects on liver fibrosis in vitro. The present study was investigated to verify protective effects of FLYQ on liver fibrosis in a rat model and to investigate the underlying mechanisms which have not been explored yet. Materials and methods: Liver fibrosis was established by intragastric administration of 2ml/kg CCl4 twice a week for 12 weeks. During the experiment, the model group received CCl4 only, and the normal control group received an equal volume of saline. Treatment groups received not only CCl4 for 12 weeks, but also the corresponding drugs, colchicine (1.00mg/kg/day) or FLYQ (300, 150, 75mg/kg/day) from 5 to 12 weeks. Results: Analysis experiments showed that FLYQ could significantly alleviate liver injury, as indicated by decreasing levels of ALT, AST, ALP, GGT, IL-6 and TNF-α. Moreover, FLYQ could effectively inhibit collagen deposition and reduce the pathological tissue damage. Research on mechanism showed that FLYQ was able to markedly reduce lipid peroxidation, recruit the anti-oxidative defense system, promote ECM degradation by modulating the levels of TIMP-1 and MMP-2, and induce HSC apoptosis by down-regulating bcl-2 mRNA, as well as inhibit the expressions of α-SMA and TGF-β1 proteins. Conclusions: Our results show that FLYQ is effective in attenuating hepatic injury and fibrosis in the CCl4-induced rat model, which should be developed as a new drug for treatment of liver fibrosis and even cirrhosis. [Copyright &y& Elsevier]

Objective. To investigate the potential active ingredients and underlying mechanisms of Artemisia annua (AA) on the treatment of hepatocellular carcinoma (HCC) based on network pharmacology. Methods. In the present study, we used a network pharmacological method to predict its underlying complex mechanism of treating HCC. First, we obtained relative compounds of AA based on the traditional Chinese medicine systems pharmacology (TCMSP) database and collected potential targets of these compounds by target fishing. Then, we built HCC-related targets target by the oncogenomic database of hepatocellular carcinoma (OncoDB.HCC) and biopharmacological network (PharmDB-K) database. Based on the matching results between AA potential targets and HCC targets, we built a protein-protein interaction (PPI) network to analyze the interactions among these targets and screen the hub targets by topology. Furthermore, the function annotation and signaling pathways of key targets were performed by Gene Oncology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis using DAVID tools. Finally, the binding capacity between active ingredients and key targets was validated by molecular docking. Results. A total of 19 main active ingredients of AA were screened as target prediction; then, 25 HCC-related common targets were seeked out via multiple HCC databases. The areas of nodes and corresponding degree values of EGFR, ESR1, CCND1, MYC, EGF, and PTGS2 were larger and could be easily found in the PPI network. Furthermore, GO and KEGG enrichment analysis showed that these key targets were significantly involved in multiple biological processes and pathways which participated in tumor cell proliferation, apoptosis, angiogenesis, tumor invasion, and metastasis to accomplish the anti-HCC activity. The molecular docking analysis showed that quercetin could stably bind to the active pocket of EGFR protein 4RJ5 via LibDock. Conclusion. The anticancer effects of AA on HCC were predicted to be associated with regulating tumor cell proliferation, apoptosis, angiogenesis, tumor invasion, and metastasis via various pathways such as the EGFR signaling pathway, ESR1 signaling pathway, and CCND1 signaling pathway. It is suggested that AA might be developed as a broad-spectrum antitumor drug based on its characteristics of multicomponent, multipath, and multitarget. [ABSTRACT FROM AUTHOR]

Our previous study demonstrated that neuroglobin (Ngb) functions as an independent predictive indicator of the prognosis of patients with glioma and promotes cancer cell growth by suppressing apoptosis. However, the understanding of the mechanisms underlying the survival-enhancing function of Ngb in glioma is limited. In the present study, KEGG PathwayFinder by gene correlation analysis was performed on the R2: Genomics Analysis and Visualization Platform, which revealed a high association between Ngb and the phosphatidylinositol 3-kinase (PI3K)/AKT pathway using glioma data (GSE4290) from the Gene Expression Omnibus database. Furthermore, western blotting experiments were performed in U251 and U87 glioma cells, and Ngb knockdown using short hairpin RNA reduced the protein levels of phosphorylated (p)-AKT, p-mammalian target of rapamycin (mTOR) and antiapoptotic factor Bcl-2, and increased the expression of the proapoptotic protein Bcl-2-associated X, in U251 cells. In addition, Ngb overexpression promoted the activation of the PI3K/AKT pathway in U87 cells. MK2206, a PI3K/AKT signaling inhibitor, reduced the expression of p-AKT and increased the levels of apoptosis-associated proteins, including cleaved poly(ADP-ribose) polymerase 1 and cleaved caspase-3/7/8, in Ngb-overexpressing U87 cells. Furthermore, MK2206 treatment reduced the proliferation and induced the apoptosis of Ngb-overexpressing U87 cells, as indicated by the results of MTT, colony formation and flow cytometry assays. In addition, insulin-like growth factor-1, a PI3K/AKT signaling activator, reversed Ngb knockdown-induced growth arrest and apoptosis in U251 cells. In conclusion, the results of the present study indicate that Ngb may facilitate a malignant phenotype of glioma cells by activating the PI3K/AKT pathway. [ABSTRACT FROM AUTHOR]

Multiple pathogenic factors have been suggested to play a role in the development of Alzheimer's disease (AD). The multifactorial nature of AD also suggests the potential use of compounds with polypharmacology as effective disease-modifying agents. Recently, we have developed a bivalent strategy to include cell membrane anchorage into the molecular design. Our results demonstrated that the bivalent compounds exhibited multifunctional properties and potent neuroprotection in a cellular AD model. Herein, we report the mechanistic exploration of one of the representative bivalent compounds, 17MN, in MC65 cells. Our results established that MC65 cells die through a necroptotic mechanism upon the removal of tetracycline (TC). Furthermore, we have shown that mitochondrial membrane potential and cytosolic Ca2+ levels are increased upon removal of TC. Our bivalent compound 17MN can reverse such changes and protect MC65 cells from TC removal induced cytotoxicity. The results also suggest that 17MN may function between the Aβ species and RIPK1 in producing its neuroprotection. Colocalization studies employing a fluorescent analog of 17MN and confocal microscopy demonstrated the interactions of 17MN with both mitochondria and endoplasmic reticulum, thus suggesting that 17MN exerts its neuroprotection via a multiple-site mechanism in MC65 cells. Collectively, these results strongly support our original design rationale of bivalent compounds and encourage further optimization of this bivalent strategy to develop more potent analogs as novel disease-modifying agents for AD. [ABSTRACT FROM AUTHOR]

An isoflavone was isolated from Trifolium pratense using bioassay-guided screening. The structure of this natural compound was elucidated based on its spectral data, and it was identified as pratensein. The protective effect of pratensein was evaluated using a cognitive impairment model induced by injecting amyloid beta (1–42) (Aβ 1–42 ) into the bilateral hippocampus of rats. The results showed that pratensein treatment significantly protected against Aβ 1–42 -induced cognitive impairments, as evidenced by the improvement in learning and memory and the attenuation of neuronal degeneration and apoptosis in hippocampus. Analysis of the potential mechanisms of action showed that pratensein significantly decreased inflammatory indicators such as MDA, NO, nNOS, IL-1β and TNF-α. Pratensein markedly decreased the content and deposition of β-amyloid peptide through regulating the expressions of Aβ-related genes including APP, BACE1, CatB, NEP and IDE. Moreover, pratensein significantly increased the expressions of synapse plasticity-related proteins, i.e., PSD-95, p-NMDAR1, p-CaMKII, p-PKACβ, PKCγ, p-CREB and BDNF. In addition, pratensein significantly decreased the activity of cholinesterase, then subsequently elevated the level of acetylcholine. In summary, our study indicated that pratensein may have a likely protective effect against Alzheimer's disease (AD) via improving synaptic plasticity and increasing cholinesterase activity. [ABSTRACT FROM AUTHOR]

Aims: Effect and mechanism of Yulangsan flavonoid (YLSF) on rat myocardial ischemia/reperfusion injury (MI/RI) has been investigated. Methods: Sprague-Dawley (SD) rats were randomly divided into seven groups (sham group, model group and NS group: 2 mL of normal saline/kg body weight was administered; diltiazem group: 5 mg of diltiazem hydrochloride/kg body weight was administered; YLSFL, YLSFM and YLSFH groups: 20, 40 and 80 mg of YLSF/kg body weight was administered) and the MI/RI model was established. Myocardial infarct area, levels of myocardial enzymes and nitric oxide synthase (NOS) were measured. Caspase-3 and adenine nucleotide translocator-1 (ANT1) mRNA expression were evaluated by reverse transcription polymerase chain reaction (RT-PCR). Pathological structure and cardiocyte ultrastructure were also analysed. Results: Compared with the MI/RI group, pretreatment with YLSF or diltiazem hydrochloride decreased the infarct area, levels of inducible nitric oxide synthase (iNOS), caspase-3 as well as the leakage of myocardial enzyme and increased activities of total nitric oxide synthase (tNOS) as well as constitutive nitric oxide synthase (cNOS). Cellular edema and the infiltration of inflammatory cells were alleviated. Conclusions: The experiment showed that YLSF protected the heart against MI/RI, possibly by reducing lipid peroxidation damage, regulating NOS activity and modulating the apoptosis genes expression. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

In our effort to develop selective sphingosine kinase-2 (SphK2) inhibitors as pharmacological tools, a thiazolidine-2,4-dione analogue, 3-(2-amino-ethyl)-5-[3-(4-butoxyl-phenyl)-propylidene]-thiazolidine-2,4-dione (K145), was synthesized and biologically characterized. Biochemical assay results indicate that K145 is a selective SphK2 inhibitor. Molecular modeling studies also support this notion. In vitro studies using human leukemia U937 cells demonstrated that K145 accumulates in U937 cells, suppresses the S1P level, and inhibits SphK2. K145 also exhibited inhibitory effects on the growth of U937 cells as well as apoptotic effects in U937 cells, and that these effects may be through the inhibition of down-stream ERK and Akt signaling pathways. K145 also significantly inhibited the growth of U937 tumors in nude mice by both intraperitoneal and oral administration, thus demonstrating its in vivo efficacy as a potential lead anticancer agent. The antitumor activity of K145 was also confirmed in a syngeneic mouse model by implanting murine breast cancer JC cells in BALB/c mice. Collectively, these results strongly encourage further optimization of K145 as a novel lead compound for development of more potent and selective SphK2 inhibitors. [ABSTRACT FROM AUTHOR]

Abstract: Dengue virus (DENV) capsid (C) proteins are the major structural component of virus particles. This study aimed to identify the host interacting partners of DENV C protein that could contribute to viral pathogenesis. DENV C protein was screened against human liver cDNA yeast two-hybrid library. We identified calcium modulating cyclophilin-binding ligand (CAML) as a novel interacting partner of DENV C protein. We report for the first time that CAML influenced DENV production. DENV production was significantly attenuated in CAML knock-down cells at 36h post-infection. CAML did not influence DENV entry, genome uncoating, viral transcription, viral translation and virus secretion. Our study pinpointed that CAML influenced the process of apoptosis by altering mitochondrial membrane potential and caspase-3 activation from 36h post-infection. Over-expression of CAML protected Huh7 cells from apoptosis and knock down of CAML favoured apoptosis following infection with DENV. We also showed that CAML expression was up-regulated during DENV infection. Increased CAML levels protected DENV-infected cells from undergoing apoptosis by preventing mitochondrial damage and caspase-3 activation which in turn favoured DENV production from 36h post-infection. Overall, this study demonstrated that DENV manipulated the levels of CAML to subvert the apoptotic process which in turn favoured efficient virus production. [Copyright &y& Elsevier]

Abstract: A series of 2,5-disubstituted-thiazolidine-2,4-dione analogs based on the newly identified lead 1, a potential anticancer agent via the inhibition of the Raf/MEK/extracellular signal regulated kinase (ERK) and phosphatidylinositol 3-kinase (PI3K)/Akt signaling cascades, were synthesized and biologically characterized. A new lead structure, 15, was identified to have improved anti-proliferative activities in U937 cells, to induce apoptosis in U937, M12 and DU145 cancer cells, and to arrest U937 cells at the S-phase. Furthermore, Western blot analysis demonstrated a correlation of the anti-proliferative activity and blockade of the Raf/MEK/ERK and PI3K/Akt signaling pathways. Collectively, these results strongly encourage further optimization of 15 as a new lead with multi-target properties to develop more potent compounds as anticancer agents. [Copyright &y& Elsevier]

Abstract: A thiazolidine-2,4-dione derivative, 3-(2-aminoethyl)-5-(3-phenyl-propylidene)-thiazolidine-2,4-dione (2), was identified as a dual inhibitor of the Raf/MEK/ extracellular signal-regulated kinase (ERK) and the phosphatidylinositol 3-kinase (PI3K)/Akt signaling cascades. The discovered compound inhibited cell proliferation, induced early apoptosis, and arrested cells in G0/G1 phase in human leukemia U937 cells. These results indicate its potential as a new lead compound to develop novel dual signaling pathway inhibitors and anticancer agents. [Copyright &y& Elsevier]

Abstract: A series of analogs of 3-(2-amino-ethyl)-5-(4-ethoxy-benzylidene)-thiazolidine-2,4-dione, a putative substrate-specific ERK1/2 inhibitor, were synthesized and biologically characterized in human leukemia U937 cells to define its pharmacophore. It was discovered that shift of ethoxy substitution from the 4- to the 2-position on the phenyl ring significantly improved functional activities of inhibiting cell proliferation and inducing apoptosis. This may provide access to a new lead for developing ERK1/2 substrate-specific inhibitors. [Copyright &y& Elsevier]

The root of Averrhoa carambola L. (Oxalidaceae), a traditional Chinese medicine, was mainly used in ancient times in the treatment of urinary calculi, recurrent headache and joint pain. Our aims were to explore the potential therapeutic effect of the extract of Averrhoa carambola L. (Oxalidaceae) roots (EACR) against hepatic fibrosis in CCl 4 -treated rats and to understand the underlying molecular mechanism. Six groups of male Sprague Dawley rats were treated as follows: vehicle (olive oil), CCl 4 alone, CCl 4 +colchicine, CCl 4 +EACR 1.0 g/kg, CCl 4 +EACR 0.5 g/kg and CCl 4 +EACR 0.25 g/kg. At the end of the 12th week, biomarkers of liver function, liver fibrosis, hepatic oxidative stress and antioxidant status were assayed, and histopathological and immunohistochemical evaluation of liver tissue were conducted to investigate the liver damage and fibrosis degree. Furthermore, expressions of COL-1a1, α-SMA, TGF-β1, Smad2, smad3, Smad4 and TIMP2 were examined by qPCR and/or western blot. The expressions of apoptosis-related proteins were also detected using western blot analysis. EACR treatment markedly reduced the CCl 4 -induced elevation of serum aminotransferase activities, liver fibrosis indexes, and the extent of oxidative stress. EACR treatment also significantly reduced the accumulation of collagen and the immunostaining of α-SMA, TGF-β1 and Smad2, 4 and 7 in the liver of CCl 4 treated rats. In addition, EACR treatment markedly reversed the CCl 4 -induced increase in mRNA expression of COL-1a1, α-SMA, TIMP2, TGF-β1, Smad2 and Smad4 and suppressed the expressions of α-SMA, TIMP2, TGF-β1, smad2, 3 and 4, BAX and cleaved caspase-3 proteins. Meanwhile, EACR treatment also significantly elevated the mRNA expression of Smad7 and the protein expression of Smad7 and Bcl-2. These results suggest that EACR has protective activity against liver fibrosis. The anti-fibrotic activity of EACR in vivo is associated with enhanced antioxidant, apoptosis-inhibition and increased MMP-2/TIMP-2 expression ratio, and with modulation of TGF-β1/Smad signaling pathway. [ABSTRACT FROM AUTHOR]