ER-residential Nogo-B accelerates NAFLD-associated HCC mediated by metabolic reprogramming of oxLDL lipophagy.

Non-alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome that elevates the risk of hepatocellular carcinoma (HCC). Although alteration of lipid metabolism has been increasingly recognized as a hallmark of cancer cells, the deregulated metabolic modulation of HCC cells in the NAFLD progression remains obscure. Here, we discovers an endoplasmic reticulum-residential protein, Nogo-B, as a highly expressed metabolic modulator in both murine and human NAFLD-associated HCCs, which accelerates high-fat, high-carbohydrate diet-induced metabolic dysfunction and tumorigenicity. Mechanistically, CD36-mediated oxLDL uptake triggers CEBPß expression to directly upregulate Nogo-B, which interacts with ATG5 to promote lipophagy leading to lysophosphatidic acid-enhanced YAP oncogenic activity. This CD36-Nogo-B-YAP pathway consequently reprograms oxLDL metabolism and induces carcinogenetic signaling for NAFLD-associated HCCs. Targeting the Nogo-B pathway may represent a therapeutic strategy for HCC arising from the metabolic syndrome.

Cardioprotective effects of monocyte locomotion inhibitory factor on myocardial ischemic injury by targeting vimentin.

Monocyte locomotion inhibitory factor (MLIF), a heat-stable pentapeptide produced by Entamoeba histolytica, has anti-inflammatory function and protective effect on ischemic stroke. In this study, we evaluated the effect of MLIF on myocardial ischemia. Mice were subjected to ischemia/reperfusion by occlusion of the left anterior descending artery (LAD). After sacrifice, the serum concentrations of cardiac troponin I (cTnI), creatine kinase (CK), lactate dehydrogenase (LDH) as well as the heart infarct size were measured. HE and TUNEL staining were used to observe the pathological damage and the apoptotic cells. For in vitro study, the oxygen-glucose deprivation(OGD) model was established in H9c2 cells. MTT assay and flow cytometry assay were performed to evaluate cell viability and apoptosis. The expression of JNK and caspase 3 was assessed by western blot analysis. Pull-down assay was used to detect the specific binding protein of MLIF in myocardial cells. MLIF significantly reduced the infarct size, and the cTnI, CK and LDH levels, amelioratived pathological damage and reduced the apopotosis compared with the myocardial I/R model group. MLIF improved cell survival and inhibited apoptosis and necrosis by inhibiting the p-JNK and cleaved caspase3 expression. Furthermore, the binding protein of MLIF in myocardial cells was vimentin. Inhibition of vimentin expression by withaferin A or vimentin siRNA repressed the protective effects of MLIF in OGD-provoked H9c2 cells. Taken together, our results demonstrate that the cardioprotective effects of MLIF on myocardial ischemia injury are related to reductions in the inflammatory response and apoptosis by targeting vimentin.

EF1A1/HSC70 Cooperatively Suppress Brain Endothelial Cell Apoptosis via Regulating JNK Activity.

AIMS: In our previous study, eEF1A1 was identified to be a new target for protecting brain ischemia injury, but the mechanism remains largely unknown. In this study, we screened the downstream cellular protein molecules interacted with eEF1A1 and found mechanism of eEF1A1 in brain ischemia protection. METHODS AND RESULTS: Through co-immunoprecipitation and mass spectrometry for searching the interaction of proteins with eEF1A1 in bEnd3 cells, HSC70 was identified to be a binding protein of eEF1A1, which was further validated by Western blot and immunofluorescence. eEF1A1 or HSC70 knockdown, respectively, increased OGD-induced apoptosis of brain vascular endothelial cells, which was detected by Annexin V-FITC/PI staining. HSC70 or eEF1A1 knockdown enhances phosphorylated JNK, phosphorylation of c-JUN (Ser63, Ser73), cleaved caspase-9, and cleaved caspase-3 expression, which could be rescued by JNK inhibitor. CONCLUSION: In summary, our data suggest that the presence of chaperone forms of interaction between eEF1A1 and HSC70 in brain vascular endothelial cells, eEF1A1 and HSC70 can play a protective role in the process of ischemic stroke by inhibiting the JNK signaling pathway activation.

MLIF Alleviates SH-SY5Y Neuroblastoma Injury Induced by Oxygen-Glucose Deprivation by Targeting Eukaryotic Translation Elongation Factor 1A2.

Monocyte locomotion inhibitory factor (MLIF), a heat-stable pentapeptide, has been shown to exert potent anti-inflammatory effects in ischemic brain injury. In this study, we investigated the neuroprotective action of MLIF against oxygen-glucose deprivation (OGD)-induced injury in human neuroblastoma SH-SY5Y cells. MTT assay was used to assess cell viability, and flow cytometry assay and Hoechst staining were used to evaluate apoptosis. LDH assay was used to exam necrosis. The release of inflammatory cytokines was detected by ELISA. Levels of the apoptosis associated proteins were measured by western blot analysis. To identify the protein target of MLIF, pull-down assay and mass spectrometry were performed. We observed that MLIF enhanced cell survival and inhibited apoptosis and necrosis by inhibiting p-JNK, p53, c-caspase9 and c-caspase3 expression. In the microglia, OGD-induced secretion of inflammatory cytokines was markedly reduced in the presence of MLIF. Furthermore, we found that eukaryotic translation elongation factor 1A2 (eEF1A2) is a downstream target of MLIF. Knockdown eEF1A2 using short interfering RNA (siRNA) almost completely abrogated the anti-apoptotic effect of MLIF in SH-SY5Y cells subjected to OGD, with an associated decrease in cell survival and an increase in expression of p-JNK and p53. These results indicate that MLIF ameliorates OGD-induced SH-SY5Y neuroblastoma injury by inhibiting the p-JNK/p53 apoptotic signaling pathway via eEF1A2. Our findings suggest that eEF1A2 may be a new therapeutic target for ischemic brain injury.

Antitumor Activity of cGAMP via Stimulation of cGAS-cGAMP-STING-IRF3 Mediated Innate Immune Response.

Immunotherapy is one of the key strategies for cancer treatment. The cGAS-cGAMP-STING-IRF3 pathway of cytosolic DNA sensing plays a pivotal role in antiviral defense. We report that the STING activator cGAMP possesses significant antitumor activity in mice by triggering the STING-dependent pathway directly. cGAMP enhances innate immune responses by inducing production of cytokines such as interferon-ß, interferon-γ, and stimulating dendritic cells activation, which induces the cross-priming of CD8(+) T cells. The antitumor mechanism of cGAMP was verified by STING and IRF3, which were up-regulated upon cGAMP treatment. STING-deficiency dramatically reduced the antitumor effect of cGAMP. Furthermore, cGAMP improved the antitumor activity of 5-FU, and clearly reduced the toxicity of 5-FU. These results demonstrated that cGAMP is a novel antitumor agent and has potential applications in cancer immunotherapy.

Determination of an unstable pentapeptide, monocyte locomotion inhibitory factor, in dog blood by LC-MS/MS: application to a pharmacokinetic study.

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and established for the quantitative determination of monocyte locomotion inhibitory factor, a pentapeptide (Met-Gln-Cys-Asn-Ser) produced by Entamoeba histolytica in axenic culture, in dog blood. The main challenge was the chemical and enzymatic instability of the peptide which was successfully overcome. After a simple protein precipitation, MLIF was separated from AS-5 (Met-Gln-Gly-Asn-Ser), acted as an internal standard, on a Gemini C18 column (5 µm, 50 mm × 4.6 mm i.d.) using a gradient elution of acetonitrile (0.2% formic acid) and water (0.2% formic acid) and detected by electrospray ionization tandem mass spectrometry. Excellent linearity was achieved (r>0.9943) over the linear range 5-1000 ng/ml using 0.2 ml blood sample. The validation results demonstrated that this method was specific, accurate and precise. It was successfully applied in measuring MLIF following intravenous infusion its administration at 0.2, 0.4, and 0.8 mg/kg in beagle dogs to support the pre-clinical pharmacokinetic study.

miR-126 and miR-126* repress recruitment of mesenchymal stem cells and inflammatory monocytes to inhibit breast cancer metastasis.

The tumour stroma is an active participant during cancer progression. Stromal cells promote tumour progression and metastasis through multiple mechanisms including enhancing tumour invasiveness and angiogenesis, and suppressing immune surveillance. We report here that miR-126/miR-126(*), a microRNA pair derived from a single precursor, independently suppress the sequential recruitment of mesenchymal stem cells and inflammatory monocytes into the tumour stroma to inhibit lung metastasis by breast tumour cells in a mouse xenograft model. miR-126/miR-126(*) directly inhibit stromal cell-derived factor-1 alpha (SDF-1α) expression, and indirectly suppress the expression of chemokine (C-C motif) ligand 2 (Ccl2) by cancer cells in an SDF-1α-dependent manner. miR-126/miR-126(*) expression is downregulated in cancer cells by promoter methylation of their host gene Egfl7. These findings determine how this microRNA pair alters the composition of the primary tumour microenvironment to favour breast cancer metastasis, and demonstrate a correlation between miR-126/126(*) downregulation and poor metastasis-free survival of breast cancer patients.

3ß,5α,6ß-Oxygenated sterols from the South China Sea gorgonian Muriceopsis flavida and their tumor cell growth inhibitory activity and apoptosis-inducing function.

Three new polyhydroxysterols, named muriflasteroids A-C (1-3) were isolated from the South China Sea gorgonian Muriceopsis flavida, together with sixteen known analogs, cholest-3ß,5α,6ß-triol,3ß-acetate (4), 5α-methoxycholest-3ß,6ß-diol (5), (22E)-cholest-22-en-3ß,5α,6ß-triol (6), cholest-3ß,5α,6ß-triol (7), (22E)-24-norcholest-22-en-3ß,5α,6ß-triol (8), (22E,24S)-ergost-22-en-3ß,5α,6ß-triol (9), ergost-24(28)-en-3ß,5α,6ß-triol (10), (22E)-cholest-7,22-dien-3ß,5α,6ß-triol (11), cholest-7-en-3ß,5α,6ß-triol (12), (22E)-24-norcholest-7,22-dien-3ß,5α,6ß-triol (13), ergost-7,24(28)-dien-3ß,5α,6ß-triol (14), (22E,24R)-ergost-7,22-dien-3ß,5α,6ß-triol (15), (22E)-cholest-22-en-1ß,3ß,5α,6ß-tetrol (16), (22E)-24-norcholest-22-en-1ß,3ß,5α,6ß-tetrol (17), cholest-1ß,3ß,5α,6ß-tetrol (18), and (24ξ)-ergost-1ß,3ß,5α,6ß-tetrol (19). The structures of the new compounds were elucidated by detailed spectroscopic analysis in combination with comparison of reported data. All the compounds are reported for the first time from the animal. In the bioassay in vitro, these compounds exhibited different levels of growth inhibition activity against A549 and MG63 cell lines. In particular, compound 18 displayed a considerable activity, being similar as that of positive control adriamycin. An annexin V analysis indicated that compounds 7 and 18 can significantly induce apoptosis in A549 cell, and compound 7 is more potent in the induction of apoptosis. Preliminary structure-activity analysis suggests that the acetylation on 3-OH and appearance of Δ7 may decrease the activity while substitution of 1-OH and the nature of side chain may also play an important role in the activity. Methylation of 5-OH contributed a little to the activity.

Therapeutic effects of astragaloside IV on myocardial injuries: multi-target identification and network analysis.

Astragaloside IV (AGS-IV) is a main active ingredient of Astragalus membranaceus Bunge, a medicinal herb used for cardiovascular diseases (CVD). In this work, we investigated the therapeutic mechanisms of AGS-IV at a network level by computer-assisted target identification with the in silico inverse docking program (INVDOCK). Targets included in the analysis covered all signaling pathways thought to be implicated in the therapeutic actions of all CVD drugs approved by US FDA. A total of 39 putative targets were identified. Three of these targets, calcineurin (CN), angiotensin-converting enzyme (ACE), and c-Jun N-terminal kinase (JNK), were experimentally validated at a molecular level. Protective effects of AGS-IV were also compared with the CN inhibitor cyclosporin A (CsA) in cultured cardiomyocytes exposed to adriamycin. Network analysis of protein-protein interactions (PPI) was carried out with reference to the therapeutic profiles of approved CVD drugs. The results suggested that the therapeutic effects of AGS-IV are based upon a combination of blocking calcium influx, vasodilation, anti-thrombosis, anti-oxidation, anti-inflammation and immune regulation.

MicroRNA-1 inhibits proliferation of hepatocarcinoma cells by targeting endothelin-1.

AIMS: MicroRNA-1 (miR-1) has been demonstrated as a tumor-suppressive miRNA, which shows a down-regulated pattern in several human malignancies including hepatocellular carcinoma (HCC). However, the pathophysiologic roles of miR-1 and their mechanisms in HCC tumorigenesis are still not totally elucidated. MAIN METHODS: Pre-miR-1 was cloned into pSuper plasmid to overexpress the miR-1 in hepatoma cells. Real-time PCR and Western blot were applied to detect miR-1, ET-1 mRNA and protein levels respectively. Dual luciferase reporter assay was conducted to investigate the binding site of miR-1 on 3'UTR of ET-1 mRNA. Proliferation of hepatoma cells was evaluated by MTT assay. KEY FINDINGS: We observed that over-expression of miR-1 by miRNA-expressing plasmid transfection in HepG2 and Hep3B cells significantly reduced the proliferation of these cells. To explore the mechanism, we examined the potential target genes of miR-1 by bioinformatics. A potent mitogen, Endothelin-1 (ET-1), attracted our attention. Elevated expression of ET-1 but reduced miR-1 level was detected both in human liver cancer tissues and in hepatoma cell lines using Western Blot and miRNA real-time PCR respectively. By the over-expression and inhibition of miR-1 in HepG2 and Hep3B, we confirmed that miR-1 negatively regulated ET-1 expression in hepatoma cells. A luciferase reporter assay showed that miR-1 regulation was established by pairing to a complementary binding site within the ET-1 3'UTR. Finally, attenuated proliferation of hepatoma cells by over-expression of miR-1 could be partially restored by exogenous ET-1 treatment. SIGNIFICANCE: Our findings demonstrate that miR-1 could inhibit ET-1 expression to attenuate the proliferation of hepatoma cells.

CD133(+)CXCR4(+) colon cancer cells exhibit metastatic potential and predict poor prognosis of patients.

BACKGROUND: Colorectal cancer (CRC), which frequently metastasizes to the liver, is one of the three leading causes of cancer-related deaths worldwide. Growing evidence suggests that a subset of cells exists among cancer stem cells. This distinct subpopulation is thought to contribute to liver metastasis; however, it has not been fully explored in CRC yet. METHODS: Flow cytometry analysis was performed to detect distinct subsets with CD133 and CXCR4 markers in human primary and metastatic CRC tissues. The 'stemness' and metastatic capacities of different subpopulations derived from the colon cancer cell line HCT116 were compared in vitro and in vivo. The roles of epithelial-mesenchymal transition (EMT) and stromal-cell derived factor-1 (SDF-1) in the metastatic process were also investigated. A survival curve was used to explore the correlation between the content of CD133(+)CXCR4(+) cancer cells and patient survival. RESULTS: In human specimens, the content of CD133(+)CXCR4(+) cells was higher in liver metastases than in primary colorectal tumors. Clonogenic and tumorigenic cells were restricted to CD133(+) cells in the HCT116 cell line, with CXCR4 expression having no impact on the 'stemness' properties. We found that CD133(+)CXCR4(+)cancer cells had a high metastatic capacity in vitro and in vivo. Compared with CD133(+)CXCR4(-) cells, CD133(+)CXCR4(+)cancer cells experienced EMT, which contributed partly to their metastatic phenotype. We then determined that SDF-1/CXCL12 treatment could further induce EMT in CD133(+)CXCR4(+)cancer cells and enhance their invasive behavior, while this could not be observed in CD133(+)CXCR4- cancer cells. Blocking SDF-1/CXCR4 interaction with a CXCR4 antagonist, AMD3100 (1,10-[1,4-phenylenebis(methylene)]bis-1,4,8,11 -tetraazacyclotetradecane octahydrochloride), inhibited metastatic tumor growth in a mouse hepatic metastasis model. Finally, a high percentage of CD133(+)CXCR4(+)cells in human primary CRC was associated with a reduced two-year survival rate. CONCLUSIONS: Strategies targeting the SDF-1/CXCR4 interaction may have important clinical applications in the suppression of colon cancer metastasis. Further investigations on how high expression of CXCR4 and EMT occur in this identified cancer stem cell subset are warranted to provide insights into our understanding of tumor biology.

A pentapeptide monocyte locomotion inhibitory factor protects brain ischemia injury by targeting the eEF1A1/endothelial nitric oxide synthase pathway.

BACKGROUND AND PURPOSE: Ischemic stroke is a major cause of death worldwide but lacks viable treatment or treatment targets. Monocyte locomotion inhibitory factor (MLIF) is a small heat-stable pentapeptide produced by Entamoeba histolytica in axenic culture, which is supposed to protect the brain from ischemic injury; the mechanism, however, remains unknown. In this study, we further investigated the mechanism underlying the protective role of MLIF in brain ischemia. METHODS: A middle cerebral artery occlusion model in rats was used for detecting the effect of MLIF in the brain ischemia in vivo. To identify targets of MLIF in brain endothelial cells, we performed immunoprecipitation of biotin-conjugated MLIF and mass spectrometry. RESULTS: MLIF can protect the brain from ischemic injury in vivo, yielding decreased ischemic volume, prolonged survival, and improved neurological outcome. In vitro studies showed that MLIF displayed protective effects through inhibition of expression of pathological inflammatory adhesion molecules and enhancing endothelial nitric oxide synthase expression and nitric oxide release in the cerebrovascular endothelium. The target screening experiments demonstrated binding of MLIF to the ribosomal protein translation elongation factor eEF1A1. MLIF enhanced endothelial nitric oxide synthase expression through stabilization of endothelial nitric oxide synthase mRNA, and eEF1A1 was shown to be necessary for this enhanced expression. Knockdown of eEF1A1 or inhibition of endothelial nitric oxide synthase attenuated MLIF-mediated inhibition of adhesion molecule expression. CONCLUSIONS: In this study, we identified a new potential pharmacologically targetable mechanism underlying MLIF's protective effects in brain ischemia through the eEF1A1/endothelial nitric oxide synthase pathway.

Nicotinamide phosphoribosyltransferase protects against ischemic stroke through SIRT1-dependent adenosine monophosphate-activated kinase pathway.

OBJECTIVE: Stroke is a leading cause of mortality and disability. Nicotinamide phosphoribosyltransferase (Nampt) is the rate-limiting enzyme in mammalian nicotinamide adenine dinucleotide (NAD)(+) biosynthesis and contributes to cell fate decisions. However, the role of Nampt in brain and stroke remains to be investigated. METHODS: We used lentivirus-mediated Nampt overexpression and knockdown to manipulate Nampt expression and explore the effects of Nampt in neuronal survival on ischemic stress both in vivo and in vitro. We also used adenosine monophosphate (AMP)-activated kinase-α2 (AMPKα2) and silent mating type information regulation 2 homolog 1 (SIRT1) knockout mice to investigate the underlying mechanisms of Nampt neuroprotection. RESULTS: Nampt inhibition by a highly-specific Nampt inhibitor, FK866, aggravated brain infarction in experimentally cerebral ischemia rats, whereas Nampt overexpression in local brain and Nampt enzymatic product nicotinamide mononucleotide (NMN) reduced ischemia-induced cerebral injuries. Nampt overexpression and knockdown regulated neuron survival via the AMPK pathway. Neuroprotection of Nampt was abolished in AMPKα2(-/-) neurons. In neurons, Nampt positively modulated NAD(+) levels and thereby controlled SIRT1 activity. SIRT1 coprecipitated with serine/threonine kinase 11 (LKB1), an upstream kinase of AMPK, and promoted LKB1 deacetylation in neurons. Nampt-induced LKB1 deacetylation and AMPK activation disappeared in SIRT1(-/-) neurons. In contrast, Ca(2+) /calmodulin-dependent protein kinase kinase-ß (CaMKK-ß), another upstream kinase of AMPK, was not involved in the neuroprotection of Nampt. More important, Nampt overexpression-induced neuroprotection was abolished in SIRT1(+/-) and AMPKα2(-/-) mice. INTERPRETATION: Our findings reveal that Nampt protects against ischemic stroke through rescuing neurons from death via the SIRT1-dependent AMPK pathway and indicate that Nampt is a new therapeutic target for stroke.

MicroRNA-125a/b-5p inhibits endothelin-1 expression in vascular endothelial cells.

BACKGROUND: Endothelin-1 (ET-1) is considered to be one of the most potent and long-lasting vasoconstrictive peptides, but the mechanisms on the regulation of ET-1 expression are not fully understood. METHOD AND RESULTS: In this study, we found that microRNA (miR)-125a-5p and miR-125b-5p are highly expressed in vascular endothelial cells (VECs), which can be regulated by oxidized low-density lipoprotein (oxLDL). To explore the function of miR-125a/b-5p in VECs, we examined the roles of potential targets of miR-125a/b-5p that could influence endothelium function. We found that both miR-125a/b-5p can suppress oxLDL-induced ET-1 expression by directly targeting 3' untranslated region of prepro-endothelin-1 (preproET-1) mRNA determined by luciferase reporter assay, western blot, and enzyme immunometric assay. Consistently, inhibitors of miR-125a/b-5p can directly enhance preproET-1 expression. The decreased expressions of miR-125a-5p and miR-125b-5p are negatively associated with upregulation of preproET-1 expression in aorta of stroke-prone spontaneously hypertensive rats (SHR-SPs). CONCLUSION: Our finding demonstrated that endothelial miR-125a/b-5p inhibits ET-1 expression in VECs, which revealed a novel miRNA-mediated mechanism in vasomotor homeostasis.

The cytosolic nucleic acid sensor LRRFIP1 mediates the production of type I interferon via a beta-catenin-dependent pathway.

Intracellular nucleic acid sensors detect microbial RNA and DNA and trigger the production of type I interferon. However, the cytosolic nucleic acid-sensing system remains to be fully identified. Here we show that the cytosolic nucleic acid-binding protein LRRFIP1 contributed to the production of interferon-beta (IFN-beta) induced by vesicular stomatitis virus (VSV) and Listeria monocytogenes in macrophages. LRRFIP1 bound exogenous nucleic acids and increased the expression of IFN-beta induced by both double-stranded RNA and double-stranded DNA. LRRFIP1 interacted with beta-catenin and promoted the activation of beta-catenin, which increased IFN-beta expression by binding to the C-terminal domain of the transcription factor IRF3 and recruiting the acetyltransferase p300 to the IFN-beta enhanceosome via IRF3. Therefore, LRRFIP1 and its downstream partner beta-catenin constitute another coactivator pathway for IRF3-mediated production of type I interferon.

NDRG2 induced by oxidized LDL in macrophages antagonizes growth factor productions via selectively inhibiting ERK activation.

During atherogenesis, macrophage foam cells produce prodigious growth factors, cytokines, and chemokines, which play the central roles in inflammatory process in atherosclerotic plaque formation. In the present study, we identified a new protein marker, N-Myc downstream-regulated protein 2 (NDRG2), which is significantly up-regulated in oxidized low density lipoprotein (oxLDL) treated macrophages and in human atherosclerotic plaques. Over-expression and siRNA knockdown studies showed that NDRG2 is a negative regulator of platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) productions in macrophages. Furthermore, we investigated the effects of NDRG2 on MAPK signal activation. Our results showed ERK1/2 activation, but not P38 or JNK1/2 activation, is responsible for regulation of NDRG2 on VEGF and PDGF productions. Consistent with the PDGF levels, the vascular smooth muscle cell (VSMC) proliferation was also regulated by the conditional medium of the oxLDL treated macrophages with NDRG2 knockdown or over-expression. Neutralizing anti-PDGF antibody can significantly inhibit the enhanced VSMC proliferation by macrophage medium with NDRG2 knockdown. Our present results demonstrate that NDRG2 participates in oxLDL-induced macrophage activation and modulates ERK1/2-dependent PDGF and VEGF production, which has potential application in atherogenesis.

Lentiviral vector-mediated siRNA knockdown of SR-PSOX inhibits foam cell formation in vitro.

AIM: To investigate the expression of scavenger receptor that binds phosphatidylserine and oxidized lipoprotein (SR-PSOX)/CXC chemokine ligand 16 (CXCL16) in the human monocyte-derived cell line THP-1, and the effect of lentiviral vectors for the stable delivery of SR-PSOX/CXCL16 short hairpin RNA on foam cell formation. METHODS: A lentiviral expression vector containing enhanced green fluorescence protein (GFP) and SR-PSOX small interfering RNA (siRNA) (Lenti-SR-PSOXsi), or the control siRNA (Lenti-NC) gene was constructed. A human monocyte-derived cell line THP-1 was transfected with a different multiplicity of infection (MOI) of Lenti-SR-PSOXsi or Lenti-NC, and cultured to obtain stably-transfected THP- 1KD and THP-1NC cells. After incubation with oxidatively-modified, low-density lipoprotein (Ox-LDL), the expression of SR-PSOX/CXCL16 mRNA was determined by real-time PCR. The expression of the SR-PSOX/CXCL16 protein was detected by flow cytometry analysis. The effect of Lenti-SR-PSOXsi on foam cell formation was assessed by Oil red O-stain analysis. RESULTS: Ox-LDL increased the expression of SR-PSOX/CXCL16 mRNA in a time- and dose-dependent manner in THP-1 cells. Four days after transfection with Lenti-SR-PSOXsi (MOI: 100), the percentage of GFP expression cells was over 89.3%. The expression of the SR-PSOX/ CXCL16 mRNA and protein in THP-1KD cells significantly decreased compared with the parent cells, even the THP-1KD cells stimulated with 40 mg/L Ox-LDL. Ox-LDL uptake experiments in THP-1- and THP-1KD-derived macrophages indicated that SR-PSOX/CXCL16 deficiency decreased the development of macrophage- derived foam cell formation. CONCLUSION: The above data showed that SRPSOX siRNA delivered by using lentiviral vectors in THP-1 cells was a powerful tool for studying the effect of SR-PSOX, and decreased the expression of the SRPSOX gene by inhibiting macrophage-derived foam cell formation.

Adenovirus viral interleukin-10 inhibits adhesion molecule expressions induced by hypoxia/reoxygenation in cerebrovascular endothelial cells.

AIM: To investigate the effects of recombinant adenovirus encoding viral interleukin-10 (vIL-10), a potent anti-inflammatory cytokine, on adhesion molecule expressions and the adhesion rates of leukocytes to endothelial cells in cerebrovascular endothelial cells injured by hypoxia/reoxygenation (H/R). METHODS: A recombinant adenovirus expressing vIL-10 (Ad/vIL-10 (or the green fluorescent protein (Ad/GFP) gene was constructed. A cerebrovascular endothelial cell line bEnd.3 was pretreated with a different multiplicity of infection (MOI) of Ad/vIL-10 or Ad/GFP and then exposed to hypoxia for 9 h followed by reoxygenation for 12 h. The culture supernatants were tested for the expression of vIL-10 and endogenous murine IL-10 (mIL-10) by ELISA. The effects of Ad/vIL-10 on monocyte-endothelial cell adhesion were represented as the adhesion rate. Subsequently, the expressions of intercellular adhesion molecule 1(ICAM-1) and vascular cell adhesion molecule 1( VCAM-1) in the endothelial cells after treatment with Ad/vIL-10 and H/R were analyzed by Western blotting and real-time PCR. RESULTS: vIL-10 was expressed in cultured bEnd.3 after Ad/vIL-10 transfection and was significantly increased by H/R. Ad/vIL-10 or Ad/GFP did not affect the mIL-10 level. H/R increased the mIL-10 expression, but insignificantly. Monocyte- endothelial cell adhesion induced by H/R was significantly inhibited by pretreatment with Ad/vIL-10(MOI:80). ICAM-1, and VCAM-1 in bEnd.3 and were significantly increased after H/R, while pretreatment with Ad/vIL-10 (MOI: 80) significantly inhibited their expressions. Ad/GFP did not markedly affect monocyte- endothelial adhesion and the expressions of ICAM-1 and VCAM-1 induced by H/R. CONCLUSION: Ad/vIL-10 significantly inhibits the upregulation of endothelial adhesion molecule expressions and the increase of adhesion of monocytes- endothelial cells induced by H/R, indicating that vIL-10 gene transfer is of farreaching significance in the therapy of cerebrovascular inflammatory diseases, and anti-adhesion treatment may reduce H/R injury.

Adenoviral gene transfer of viral interleukin-10 protects cerebrovascular impairment induced by lysophosphatidylcholine.

Cerebrovascular disease is a significant cause of morbidity and mortality in the world. Inflammatory processes induce several pathological responses such as atherosclerosis, which have fundamental roles in stroke in the etiology of ischemic cerebrovascular disease and the pathophysiology of cerebral ischemia. Viral interleukin-10 (vIL-10), a potential anti-inflammatory cytokine, has been studied extensively. However, the efficacy of vIL-10 on cerebrovascular dysfunction is not well known. Our goal in this study was to explore the effect of gene transfer of vIL-10 mediated by adenovirus (Ad/vIL-10) on cerebrovascular function using a model of vasocontraction of isolated basilar artery from mongrel dogs induced by lysophosphatidylcholine (lysoPC), a proinflammatory and atherogenic serum lysophospholipid. To clarify the relation between contraction of basilar aorta and cell adhesion and adhesion molecules, our further study explored effects of Ad/vIL-10 on monocyte-cerebrovascular endothelial cells adhesion and expression of cell adhesion molecule by cultured cerebromicrovascular endothelial cells, bEnd.3, after incubation by lysoPC. Our results showed that Ad/vIL-10 significantly decreased contractive response of basilar aorta produced by lysoPC and augmented vasorelaxation to acetylcholine. Further studies showed the Ad/vIL-10 significantly depressed adherence of monocytes to cerebrovascular endothelial cells and inhibited up-regulation of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) which are bio-markers in inflammatory progress. These data demonstrated the protective effects of Ad/vIL-10 on cerebrovascular dysfunction induced by inflammation, and proved that inhibition of expression of cell adhesion molecules should be one of ways of vIL-10 to protect vascular function during inflammation.

Effects of Ginkgo biloba extract on expressions of IL-1beta, TNF-alpha, and IL-10 in U937 foam cells.

This study is to investigate the protein and mRNA expressions of pro-inflammatory and anti-inflammatory cytokines in U937 foam cells and effects of Ginkgo biloba extract (GbE) on the cytokines. U937 cells were cultured with different concentrations of GbE (0.1, 1, and 10 microg x L(-1)), and stimulated by 100 mg x L(-1) oxidized low density lipoprotein (ox-LDL) for 24 h. The expressions of interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) in culture solution were detected by enzyme-linked immunosorbant assay (ELISA) and reverse transcriptase polymerase chain reaction (RT-PCR). The results showed that incubated with 100 mg x L(-1) ox-LDL for 24 h, the U937 cells became foam cells, the protein or mRNA expressions of IL-1beta, TNF-alpha, IL-10, and its receptor IL-10R in U937 foam cells were higher markedly than those in normal U937 cells. When the cells were pretreated with GbE (0.1, 1, and 10 microg x L(-1)), the increases of IL-1beta and TNF-alpha in U937 foam cells were remarkably inhibited, but IL-10 expression increased greatly. Especially when cells were pretreated with 10 microg x L(-1) GbE, the protein and mRNA expressions of IL-1beta and TNF-alpha were markedly lower than those in U937 foam cells. The protein expression of IL-10 and mRNA expressions of IL-10 and its receptor IL-10R were markedly higher than those in U937 foam cells. GbE inhibited production of pro-inflammatory cytokines IL-1beta and TNF-alpha, but up-regulated the production of anti-inflammatory cytokine IL-10 and its receptor IL-10R in U937 foam cells, which might be related with its anti-atherosclerotic actions.