BACKGROUND/AIMS: Chronic liver disease leads to liver fibrosis, and although the liver does have a certain regenerative capacity, this disease is associated with dysfunction of the liver vessels. C-reactive protein (CRP) is produced in the liver and circulated from there for metabolism. CRP was recently shown to inhibit angiogenesis by inducing endothelial cell dysfunction. The objective of this study was to determine the effect of CRP levels on angiogenesis in a rat model of liver dysfunction induced by bile duct ligation (BDL). METHODS: The diameter of the hepatic vein was analyzed in rat liver tissues using hematoxylin and eosin (H&E) staining. The expression levels of angiogenic factors, albumin, and CRP were analyzed by real-time PCR and Western blotting. A tube formation assay was performed to confirm the effect of CRP on angiogenesis in human umbilical vein endothelial cells (HUVECs) treated with lithocholic acid (LCA) and siRNA-CRP. RESULTS: The diameter of the hepatic portal vein increased significantly with the progression of cirrhosis. The expression levels of angiogenic factors were increased in the cirrhotic liver. In contrast, the expression levels of albumin and CRP were significantly lower in the liver tissue obtained from the BDL rat model than in the normal liver. The CRP level was correlated with the expression of albumin in hepatocytes treated with LCA and siRNA-CRP. Tube formation was significantly decreased in HUVECs when they were treated with LCA or a combination of LCA and siRNA-CRP. CONCLUSION: CRP seems to be involved in the abnormal formation of vessels in hepatic disease, and so it could be a useful diagnostic marker for hepatic disease.
Angiogenic Proteins/genetics/metabolism ; Animals ; Bile Ducts/surgery ; C-Reactive Protein/*analysis/genetics/metabolism ; Cells, Cultured ; Disease Models, Animal ; Hepatic Veins/abnormalities ; Hepatocytes/cytology/metabolism ; Human Umbilical Vein Endothelial Cells ; Humans ; Lithocholic Acid/pharmacology ; Liver/metabolism/pathology ; Liver Cirrhosis/etiology ; Liver Diseases/metabolism/*pathology ; Male ; Microscopy, Fluorescence ; Mitochondria/drug effects/metabolism ; RNA Interference ; RNA, Small Interfering/metabolism ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Serum Albumin/genetics/metabolism

Chloroquine ; pharmacology ; Down-Regulation ; Gene Expression ; drug effects ; HEK293 Cells ; Humans ; Leupeptins ; pharmacology ; Membrane Proteins ; antagonists & inhibitors ; genetics ; metabolism ; Microscopy, Fluorescence ; Protein Binding ; Protein Subunits ; genetics ; metabolism ; RNA Interference ; RNA, Small Interfering ; metabolism ; Shab Potassium Channels ; genetics ; metabolism

The methylcytosine dioxygenases TET proteins (TET1, TET2, and TET3) play important regulatory roles in neural function. In this study, we investigated the role of TET proteins in neuronal differentiation using Neuro2a cells as a model. We observed that knockdown of TET1, TET2 or TET3 promoted neuronal differentiation of Neuro2a cells, and their overexpression inhibited VPA (valproic acid)-induced neuronal differentiation, suggesting all three TET proteins negatively regulate neuronal differentiation of Neuro2a cells. Interestingly, the inducing activity of TET protein is independent of its enzymatic activity. Our previous studies have demonstrated that srGAP3 can negatively regulate neuronal differentiation of Neuro2a cells. Furthermore, we revealed that TET1 could positively regulate srGAP3 expression independent of its catalytic activity, and srGAP3 is required for TET-mediated neuronal differentiation of Neuro2a cells. The results presented here may facilitate better understanding of the role of TET proteins in neuronal differentiation, and provide a possible therapy target for neuroblastoma.
Animals ; Catalytic Domain ; Cell Differentiation ; drug effects ; physiology ; Cell Line, Tumor ; DNA-Binding Proteins ; antagonists & inhibitors ; genetics ; metabolism ; Enzyme Inhibitors ; pharmacology ; GTPase-Activating Proteins ; genetics ; metabolism ; Immunohistochemistry ; Mice ; Microscopy, Fluorescence ; Neuroblastoma ; metabolism ; pathology ; Protein Isoforms ; antagonists & inhibitors ; genetics ; metabolism ; Proto-Oncogene Proteins ; antagonists & inhibitors ; genetics ; metabolism ; RNA Interference ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; metabolism ; Valproic Acid ; pharmacology

Mammalian pancreatic β-cells play a pivotal role in development and glucose homeostasis through the production and secretion of insulin. Functional failure or decrease in β-cell number leads to type 2 diabetes (T2D). Despite the physiological importance of β-cells, the viability of β-cells is often challenged mainly due to its poor ability to adapt to their changing microenvironment. One of the factors that negatively affect β-cell viability is high concentration of free fatty acids (FFAs) such as palmitate. In this work, we demonstrated that Yes-associated protein (Yap1) is activated when β-cells are treated with palmitate. Our loss- and gain-of-function analyses using rodent insulinoma cell lines revealed that Yap1 suppresses palmitate-induced apoptosis in β-cells without regulating their proliferation. We also found that upon palmitate treatment, re-arrangement of F-actin mediates Yap1 activation. Palmitate treatment increases expression of one of the Yap1 target genes, connective tissue growth factor (CTGF). Our gain-of-function analysis with CTGF suggests CTGF may be the downstream factor of Yap1 in the protective mechanism against FFA-induced apoptosis.
Actins ; metabolism ; Adaptor Proteins, Signal Transducing ; antagonists & inhibitors ; genetics ; metabolism ; Animals ; Apoptosis ; drug effects ; physiology ; Bridged Bicyclo Compounds, Heterocyclic ; pharmacology ; Cell Line, Tumor ; Connective Tissue Growth Factor ; genetics ; metabolism ; pharmacology ; Cytochalasin D ; pharmacology ; Fatty Acids, Nonesterified ; pharmacology ; HEK293 Cells ; Humans ; Immunohistochemistry ; Insulin-Secreting Cells ; cytology ; drug effects ; metabolism ; Mice ; Microscopy, Fluorescence ; Palmitic Acid ; pharmacology ; Phosphoproteins ; antagonists & inhibitors ; genetics ; metabolism ; RNA Interference ; RNA, Small Interfering ; metabolism ; Rats ; Recombinant Proteins ; genetics ; metabolism ; pharmacology ; Thiazolidines ; pharmacology

The vitamin K epoxide reductase complex subunit 1 (VKORC1), the rate-limiting enzyme for vitamin K recycling, is significantly down-regulated in the kidneys of urolithiasis patients. This study searched for direct evidence to define the inhibitory activity of VKORC1 against calcium oxalate (CaOx) crystal formation. In the experiment of VKORC1 overexpression, HK-2 cells were transfected with the pFLAG-CMV-7.1-VKORC1 plasmid as a pFLAG-CMV-7.1-VKORC1 transfection group or the pFLAG-CMV-7.1 plasmid as a pFLAG-CMV-7.1 control group. In the experiment of VKORC1 knockdown, HK-2 cells were transfected with the PGPU6/GFP/Neo-VKORC1shRNA-2 as a PGPU6/GFP/Neo-VKORC1shRNA-2 transfection group or the PGPU6/GFP/Neo-shRNA-NC plasmid as a PGPU6/GFP/Neo-shRNA-NC control group. The expression of VKORC1 in HK-2 cells was detected by real-time quantitative PCR and Western blotting. The CaOx crystal formation was observed under the laser-scanning confocal microscope. It was found that the expression levels of VKORC1 mRNA and protein were significantly higher in the pFLAG-CMV-7.1-VKORC1 transfection group than in the pFLAG-CMV-7.1 control group (P<0.01). The number of CaOx crystals in HK-2 cells incubated in fluorescently labeled CaOx monohydrate (COM) crystal medium for 48 h was 14±4 per field (100×) in the pFLAG-CMV-7.1-VKORC1 transfection group and 26±5 per field (100×) in the pFLAG-CMV-7.1 control group respectively under the laser-scanning confocal microscope. The amount of CaOx crystal aggregation and formation in the pFLAG-CMV-7.1-VKORC1 transfection group was significantly reduced as compared with the pFLAG-CMV-7.1 control group (P<0.05). The expression levels of VKORC1 mRNA and protein were significantly lower in the PGPU6/GFP/Neo-VKORC1shRNA-2 transfection group than in the PGPU6/GFP/Neo-shRNA-NC control group (P<0.05). The number of CaOx crystals in HK-2 cells incubated in fluorescently labeled COM crystal medium was 65±11 per field (100×) in the PGPU6/GFP/Neo-VKORC1shRNA-2 transfection group and 24±6 per field (100×) in the PGPU6/GFP/Neo-shRNA-NC control group respectively under the laser-scanning confocal microscope. The amount of CaOx crystal aggregation and formation in the PGPU6/GFP/Neo-VKORC1shRNA-2 transfection group was significantly increased as compared with the PGPU6/GFP/Neo-shRNA-NC control group (P<0.05). These findings suggested that the VKORC1 protein could inhibit CaOx salt crystallization, adhesion and aggregation. This research would help us to understand the mechanisms involving the interaction between crystallization and epithelial cells and the formation of CaOx.
Apoptosis ; drug effects ; Blotting, Western ; Calcium Oxalate ; chemistry ; metabolism ; pharmacology ; Cell Line ; Crystallization ; Dose-Response Relationship, Drug ; Flow Cytometry ; Gene Expression ; Green Fluorescent Proteins ; genetics ; metabolism ; Humans ; Microscopy, Confocal ; RNA Interference ; Reverse Transcriptase Polymerase Chain Reaction ; Time Factors ; Transfection ; Vitamin K Epoxide Reductases ; genetics ; metabolism

Acanthamoeba cysts are resistant to unfavorable physiological conditions and various disinfectants. Acanthamoeba cysts have 2 walls containing various sugar moieties, and in particular, one third of the inner wall is composed of cellulose. In this study, it has been shown that down-regulation of cellulose synthase by small interfering RNA (siRNA) significantly inhibits the formation of mature Acanthamoeba castellanii cysts. Calcofluor white staining and transmission electron microscopy revealed that siRNA transfected amoeba failed to form an inner wall during encystation and thus are likely to be more vulnerable. In addition, the expression of xylose isomerase, which is involved in cyst wall formation, was not altered in cellulose synthase down-regulated amoeba, indicating that cellulose synthase is a crucial factor for inner wall formation by Acanthamoeba during encystation.
Acanthamoeba castellanii/*enzymology/genetics/metabolism ; Aldose-Ketose Isomerases/*biosynthesis ; Amebiasis/*pathology ; Benzenesulfonates ; Cell Wall/chemistry/genetics/*metabolism ; Cellulose/biosynthesis ; Down-Regulation ; Encephalitis/parasitology ; Glucosyltransferases/*biosynthesis/genetics ; Keratitis/parasitology ; Microscopy, Electron, Transmission ; RNA Interference ; RNA, Small Interfering

BACKGROUNDThe discovery of water channel aquaporins (AQPs) has greatly expanded the understanding of the regulation of the water permeability of biological membranes. Aquaporin-1 (AQP1) may be involved in fluid transport in numerous pathological conditions. The objective of the present study was to examine whether AQP1 is present in cultured rat pleural mesothelial cells (PMCs) and to investigate the specific inhibitory effect of RNA interference (RNAi) on AQP1 expression in PMCs, which may provide a new method for the further studies on the relation between expression of AQP1 in PMCs and pleural fluid removal in vivo.

METHODSPMCs were isolated and cultured from rat pleura. The expression of AQP1 in PMCs was confirmed by immunocytochemical staining and reverse transcriptase-polymerase chain reaction (RT-PCR). Two eukaryotic expression plasmid vectors of short hairpin RNA (shRNA) specific for the AQP1 gene of rat sapien were designed and constructed. The recombinant plasmid vectors were transfected into cultured rat PMCs by cation liposomes. Flow cytometry was used to screen the most effective shRNA at 48 hours after transfection. The expressions of AQP1 mRNA and protein were detected by RT-PCR and Western blotting method at 48 hours after transfection.

RESULTSRT-PCR and immunostaining revealed that AQP1 mRNA and protein were present in cultured rat PMCs. Two effective eukaryotic expression plasmid vectors of shRNA specific for the AQP1 gene were constructed successfully. The levels of the expression of AQP1 were inhibited by 83.45%, 90.93%, respectively, at mRNA level and 41.24%, 67.60%, respectively at protein level by two recombinant plasmids at 48 hours after transfection. The expression of AQP1 in PMCs transfected with plasmid was significantly lower than that of the cells transfected with the control plasmid HK and that of the untransfected cells (P < 0.01). There was no significant difference in AQP1 expression between the control group and the group transfected with AQP1 nonspecific shRNAs (P < 0.05).

CONCLUSIONSThe expression of AQP1 was present in rat PMCs. The application of shRNA-AQP1 could markedly inhibit the expression of AQP1 in cultured rat PMCs. The use of RNAi is a promising tool for future research into the mechanisms of pleural fluid in vivo.

Animals ; Aquaporin 1 ; antagonists & inhibitors ; genetics ; Cells, Cultured ; Epithelial Cells ; metabolism ; Flow Cytometry ; Male ; Microscopy, Fluorescence ; Pleura ; cytology ; metabolism ; Pleural Effusion ; therapy ; RNA Interference ; RNA, Small Interfering ; genetics ; Rats

OBJECTIVETo study the role of inhibition FAK expression by FAK siRNA in liver cancer cell (MHCC97-H) adhesion, invasion and cytoskeleton rearrangement.

METHODSFAK siRNA was transfected into MHCC97-H cell by Lipofectamine 2000; then, FAK expression was detected by Western blot analysis. The change of cell adhesive and invasive ability after RNAi was checked by cell adhesive assay and cell invasive assay respectively. Meanwhile, matrix metalloproteinase-2 secretion was checked by gelatin zymography. Cytoskeleton rearrangement labeled by immunofluorescence antibody was examined by confocal laser scanning microscope.

RESULTSFAK expression in MHCC97-H cell was obviously inhibited by specific FAK siRNA; However, it was not inhibited by negative siRNA. Adhesion rate between MHCC97-H cell and extracellular matrix decreased from 57.3% to 35.8% after RNA interference (P < 0.05). Compared with untreated group, the number of cell penetrating matrigel also decreased from 31.3 +/- 2.6 to 14.5 +/- 3.1 after transfection (P < 0.05). Besides, matrix metalloproteinase-2 secretion was significantly reduced for FAK expression inhibited by FAK siRNA. FAK inhibition influenced Vinculin rearrangement, blocked the formation of lamellipodium, delayed the time of focal adhesion formation.

CONCLUSIONDown-regulation the expression of FAK can reduce adhesive rate and invasive number of MHCC97-H cell by influencing cytoskeleton rearrangement and decreasing matrix metalloproteinase-2 secretion.

Blotting, Western ; Carcinoma, Hepatocellular ; enzymology ; genetics ; pathology ; Cell Adhesion ; Cell Line, Tumor ; Cell Movement ; Cytoskeleton ; metabolism ; Fluorescent Antibody Technique ; Focal Adhesion Kinase 1 ; genetics ; metabolism ; Humans ; Liver Neoplasms ; enzymology ; genetics ; pathology ; Matrix Metalloproteinase 2 ; metabolism ; Microscopy, Confocal ; RNA Interference ; RNA, Small Interfering ; genetics ; Transfection ; methods

OBJECTIVETo construct deltaNp63 specific small hairpin RNA (shRNA) expressing plasmid,to examine its inhibitory effect to the expression of deltaNp63 protein and mRNA in transitional cell carcinoma of the bladder (TCCB) , its effect on TCCB cells cycle and proliferation.

METHODSDeltaNp63 specific oligonucleotides were designed and synthesized. These oligonucleotides were annealed to form double strand DNA fragments and this fragment was cloned into Pgenesil-1 plasmid. The recombinant deltaNp63-shRNA expression construct was confirmed by using Pst I + Sal I double digestion and by sequencing. Fluorescence staining was used to confirm the success of transfection in TCCB cells under the fluorescence microscope. The inhibitory effect of deltaNp63-shRNA construct was examined with semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemical staining assay. The cell cycle of TCCB cells was assayed by flow cytometry (FCM). The cellular proliferation of TCCB cells was assayed by tetrazolium bromide (MTT) colorimetry.

RESULTSThe deltaNp63-shRNA expression plasmid was successfully constructed and transfected into TCCB cells. It can effectively reduce the expression of deltaNp63 protein and mRNA. The reduction rate of deltaNp63 mRNA was 63.0%, and the G0/G1 ratio was increased and S phase was decreased in transfected TCCB cells. The cellular proliferation was also lower in transfected 5637 cells in comparrison with that of non-transfected TCCB cells.

CONCLUSIONA deltaNp63-shRNA expression plasmid, constructed from Pgenesil-1 plasmid, can successfully be transfected into TCCB cells and can effectively inhibit the expression of deltaNp63 protein and mRNA. It also can take part in regulation of the cell cycling and inhibit the cellular proliferation of TCCB cells.

Carcinoma, Transitional Cell ; genetics ; metabolism ; pathology ; Cell Cycle ; genetics ; physiology ; Cell Line, Tumor ; Cell Proliferation ; DNA-Binding Proteins ; biosynthesis ; genetics ; physiology ; Humans ; Immunohistochemistry ; Microscopy, Fluorescence ; Plasmids ; genetics ; RNA Interference ; RNA, Messenger ; biosynthesis ; genetics ; RNA, Small Interfering ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Trans-Activators ; biosynthesis ; genetics ; physiology ; Transcription Factors ; Transfection ; Tumor Suppressor Proteins ; biosynthesis ; genetics ; physiology ; Urinary Bladder Neoplasms ; genetics ; metabolism ; pathology

OBJECTIVETo investigate whether short interfering RNAs(siRNAs) of beta-site APP cleaving enzyme (BACE) can inhibit the expression of BACE in mammalian cells.

METHODSThe gene of EGFP, U6 promoter and beta-secretase targeting siRNA were cloned by PCR, respectively. The PCR products were inserted into plasmid pLXSN. The interfering vector pLXSN/EGFP-U6-siBACE was transferred into SK-N-SH cells to express BACE. The inhibition effect of BACE siRNA on BACE expression was investigated by fluoroscopy and immunohistochemistry method.

RESULTThe interfering vector pLXSN/EGFP-U6-siBACE was constructed successfully. The BACE siRNA inhibited the expression of BACE in the SK-N-SH cells specifically and effectively, and the production of A beta was reduced.

CONCLUSIONBACE siRNA can inhibit the expression of BACE gene of mammalian cells.

Amyloid Precursor Protein Secretases ; genetics ; metabolism ; Animals ; Green Fluorescent Proteins ; genetics ; metabolism ; Humans ; Immunohistochemistry ; Mice ; Microscopy, Fluorescence ; NIH 3T3 Cells ; Neuroblastoma ; genetics ; metabolism ; pathology ; Plasmids ; genetics ; RNA Interference ; RNA, Small Interfering ; genetics ; Recombinant Fusion Proteins ; genetics ; metabolism ; Tumor Cells, Cultured