OBJECTIVETo investigate the effects of Toll/interleukin 1 receptor domain-containing protein(TcpC)on macrophages and its mechanisms.

METHODSMurine macrophage J774A cells were co-cultured with TcpC producing wild type E. coli strain CFT073 (TcpC(wt)) or tcpc gene-deleted CFT073 mutant (TcpC(mut)) in Transwell system, respectively. Apoptosis of J774A cells co-cultured with TcpC(wt) or TcpC(mut) was analyzed by Annexin/PI double staining. The levels of reactive oxygen species (ROS) in J774A cells were determined by DCFH-DA staining after treatment with TcpC(wt) or TcpC(mut) at 6 h, 12 h,24 h or 36 h. After the ROS was scavenged by N-acetylcysteine (NAC), the changes of J774A cell apoptosis were also examined. The expression of caspase-3 in J774A cells co-cultured with TcpC(wt) or TcpC(mut) in the presence or absence of 0.1 mmol NAC was detected by Western blot.

RESULTSJ774A cells co-cultured with TcpC(wt) for 24 h or 36 h showed significantly increased apoptosis (27.39% ± 4.05% and 28.45% ± 4.55%,respectively) when compared to control group (7.96% ± 1.63% and 10.55% ± 1.44%,P<0.01) or TcpC(mut) group (11.45% ± 2.77% and 19.26%± 2.89%,P<0.01). Levels of ROS in J774A cells treated with TcpC(wt) for 24 h (108.8 ± 9.73) or 36 h (100.3 ± 10.11) were significantly higher than those in control group (56.8 ± 4.11 and 52.8 ± 4.42,P<0.01) or TcpC(mut) (69.7 ± 5.66 and 62.6 ± 4.56, P < 0.01). The pro-apoptotic effects of TcpC(wt) on J774A cells were reversed by 0.1 or 1 mMol NAC treatment. Expression of caspase-3 in J774A cells co-cultured with TcpC(wt) (0.43 ± 0.04) decreased significantly when compared to control group (0.75 ± 0.08,P<0.05) or TcpC(mut) group (0.80 ± 0.12,P<0.05). However,total caspase-3 expression was restored in J774A cells co-cultured with TcpC(wt) in the presence of 0.1 mmol NAC (0.80 ± 0.09).

CONCLUSIONTcpC can promote ROS production in macrophages,hereby inducing macrophage apoptosis.

Acetylcysteine ; pharmacology ; Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Escherichia coli ; metabolism ; Escherichia coli Proteins ; pharmacology ; Macrophages ; drug effects ; metabolism ; Mice ; Reactive Oxygen Species ; metabolism ; Virulence Factors ; pharmacology

In recent years, antibiotic resistance of bacteria has become a global health crisis. Especially, the new class of "superbug" was found in South Asia, which is resistant to almost known antibiotics and causes worldwide alarm. Through the underlying mechanisms of bacterial pathogenecity, the expression of many pathogen virulence factors is regulated by the process of quorum sensing. Screening efficient quorum sensing inhibitors is an especially compelling approach to the future treatment of bacterial infections and antibiotic resistance. This article focuses on bacterial quorum sensing system, quorum sensing screening model for in vitro and evaluation of animal models in vivo, recent research of quorum sensing inhibitors and so on.
Animals ; Anti-Bacterial Agents ; pharmacology ; therapeutic use ; Bacterial Infections ; drug therapy ; Disease Models, Animal ; Drug Resistance, Bacterial ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Pseudomonas aeruginosa ; drug effects ; pathogenicity ; physiology ; Quorum Sensing ; drug effects ; physiology ; Virulence ; drug effects ; Virulence Factors ; metabolism

Translocating protein and translocating peptides have therapeutic potential against tumors by exposing the cytotoxic domains of toxic proteins to the cell cytosol. The aim of this study is to investigate the effect of N-terminally fused PE translocating peptides on granzyme B (GrBa) activity. PE II-GrBa fusion protein genes were constructed by replacing N-terminal signal and acidic dipeptide sequence of human granzyme B gene with two truncated translocating sequences of Pseudomonas exotoxin A (PE II aa 280-364/358) by recombinant PCR, and then cloned into pIND inducible expression vector. The resulting pIND-PE II-GrBa expression vectors were co-transfected with assistant plasmid pVgRXR into HeLa cells through lipofectamine, followed by selection on G418 and zeocin. The resistant cells were collected and induced with ponasterone A. Western blot analysis demonstrated that ponasterone A induction caused the expression of PE II-GrBa fusion proteins, and indirect immunofluorescence detected giant sized multinucleated cells, suggesting cytoskeletal and mitotic abnormalities as reported in our previous studies. Western blot, enzymatic activity assay and cell counting analysis indicated that two types of PE II-GrBa fusion proteins were capable of cleaving both endogenous and exogenous substrates of granzyme B, and inhibiting the growth of cells. The PE II (aa 280-358)-GrBa was shown to have higher serine protease activity and stronger growth inhibitory effect. Such inhibition was presumably associated with G2 arrest as determined by cell cycle analysis. These data prove that PE II-GrBa fusion proteins have cell inhibitory effect similar to GrBa, and that the shorter PE-derived peptide exerts less influence on GrBa activity. This study helps to optimize the construction of recombinant protein comprising translocating peptides and cytotoxic molecules for tumor cell killing.
ADP Ribose Transferases ; genetics ; pharmacology ; Bacterial Toxins ; genetics ; pharmacology ; Cell Proliferation ; drug effects ; Exotoxins ; genetics ; pharmacology ; Granzymes ; genetics ; pharmacology ; HeLa Cells ; Humans ; Recombinant Fusion Proteins ; pharmacology ; Virulence Factors ; genetics ; pharmacology

We investigated the mechanism of Cl- secretion by fluoroaluminate(AlF4-) and sodium orthovanadate(vanadate) using the human colonic T84 cell line. T84 cell monolayers grown on collagen-coated filters were mounted in Ussing chambers to measure short circuit current(ISC). Serosal addition of AlF4- or vanadate to T84 monolayers produced a sustained increase in ISC. Removal of Ca2+ from the serosal bathing solution partially inhibited AlF4-(-)and vanadate-induced ISC, and readministration of Ca2+ restored AlF4-(-)and vanadate-induced ISC. Carbachol application in the presence of forskolin, AlF4- or vanadate induced a synergistic increase of ISC. Forskolin and vanadate significantly increased cellular cAMP level, while carbachol and AlF4- did not. Carbachol, AlF4- and vanadate significantly increased [Ca2+]i. After Na+ in mucosal bathing solution was replaced with K+, and the mucosal membrane of T84 cell was permeabilized with amphotericin B, AlF4-, vanadate, and carbachol increased K+ conductance, but forskolin did not. After sodium chloride in serosal bathing solution was replaced with sodium gluconate and the serosal membrane was permeabilized with nystatin, forskolin, AlF4-, and vanadate increased Cl- conductance, but carbachol did not. AlF4-(-)induced ISC was remarkably inhibited by the pretreatment of pertussis toxin(2 micrograms/ml) for 2 hours. These results indicate that AlF4- and vanadate can increase Cl- secretion via simultaneous stimulation of Cl- channel and K+ channel in T84 cells. However, the AlF4- action is mostly attributed to stimulation of pertussis toxin-sensitive G-proteins, whereas the vanadate action mostly results from G protein-independent mechanisms.
Aluminum/*pharmacology ; Amphotericin B/pharmacology ; Carbachol/pharmacology ; Cell Polarity ; Cells, Cultured/drug effects ; Chloride Channels/drug effects/*physiology ; Chlorides/*physiology ; Colon ; Electrophysiology ; Fluorine/*pharmacology ; Forskolin/pharmacology ; GTP-Binding Proteins/physiology ; Human ; Pertussis Toxin ; Potassium/pharmacology ; Potassium Channels/drug effects/physiology ; Second Messenger Systems ; Signal Transduction ; Support, Non-U.S. Gov't ; Vanadates/*pharmacology ; Virulence Factors, Bordetella/pharmacology

A recombinant immunotoxin named CEA/PE38/KDEL was constructed, which was composed of anti-CEA single-chain Fv and the truncated and modified form of Pseudomonas exotoxin (PE38/KDEL). The CEA/PE38/KDEL immunotoxin was expressed in the E. coli strain BL21 (DE3)-star as inclusion bodies. The denatured inclusion bodies were purified with Ni-NTA chelate agarose, then the constant gradient dialysis was used to perform the refolding of the CEA/PE38/KDEL immunotoxin. Results of FACS and MTT assay indicate that the refolded immunotoxins keep potent and specific cytotoxicity to tumor cells bearing CEA antigens.
ADP Ribose Transferases ; biosynthesis ; genetics ; pharmacology ; Antibodies ; genetics ; metabolism ; pharmacology ; Antineoplastic Agents ; metabolism ; pharmacology ; Bacterial Toxins ; biosynthesis ; genetics ; pharmacology ; Carcinoembryonic Antigen ; immunology ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Exotoxins ; biosynthesis ; genetics ; pharmacology ; Humans ; Immunoglobulin Fragments ; biosynthesis ; genetics ; Immunotoxins ; genetics ; isolation & purification ; metabolism ; pharmacology ; Protein Renaturation ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; pharmacology ; Virulence Factors ; biosynthesis ; genetics ; pharmacology

ADP Ribose Transferases ; chemistry ; pharmacology ; Animals ; Antineoplastic Agents ; pharmacology ; Bacterial Toxins ; chemistry ; pharmacology ; Exotoxins ; chemistry ; pharmacology ; Female ; HMGN2 Protein ; chemistry ; pharmacology ; HeLa Cells ; Humans ; Immunotoxins ; pharmacology ; Mice ; Mice, Inbred BALB C ; Protein Structure, Tertiary ; Recombinant Fusion Proteins ; biosynthesis ; pharmacology ; Virulence Factors ; chemistry ; pharmacology

OBJECTIVETo investigate the effect of andrographolide on virulence factors production in Pseudomonas aeruginosa.

METHODGrowth rate, pyocyanin, proteolytic activity and elastase activity were measured with or without the presence of andrographolide. The effect of andrographolide on pyocyanin production, proteolytic activity and elastase activity in PAO-JP2 was investigated simultaneously.

RESULTThe andrographolide did not affect the growth of PAO1 in planktonic culture. The production of pyocyanin, proteolytic activity and elastase activity were significanthy suppressed in P. aeruginosa cultures grown in the presence of andrographolide. However, these effects were not observed in PAO-JP2.

CONCLUSIONThe inhibiting effect of andrographolide on virulence factors production in P. aeruginosa may play a role in its anti-infection activity.

Andrographis ; chemistry ; Anti-Bacterial Agents ; pharmacology ; Diterpenes ; isolation & purification ; pharmacology ; Pancreatic Elastase ; metabolism ; Peptide Hydrolases ; metabolism ; Plants, Medicinal ; chemistry ; Pseudomonas aeruginosa ; growth & development ; metabolism ; pathogenicity ; Pyocyanine ; metabolism ; Virulence Factors ; metabolism

OBJECTIVETo investigate the effects of butyl alcohol extract of baitouweng decoction (BAEB) on the fungal cell surface hydrophobicity (CSH), filamentation and biofilm formation of Candida tropicalis.

METHODGradual dilution method was used to determine the MIC. XTT assay was applied to determine the SMIC80. Time-Kill assay was employed to draw the Time-Kill curve. The water-hydrocarbon two-phase assay was used to measure the cell surface hydrophobicity. Scanning electron microscopy (SEM) was applied to observe the morphological changes of the biofilm. Confocal laser scanning microscopy (CLSM) was applied to determine the thickness of the biofilm. The quantification real-time PCR (qRT-PCR) was used to detect expression changes of releated genes (UME6, ALST3 and NRG1). result: The MICs of BAEB against C. tropicalis strains are determined as 64-128 mg x L(-1). The SMIC80 s of BAEB against the biofilm of Candida tropicalis strains are determined as 256-512 mg x L(-1). Time-Kill curve results indicate that BAEB has a promise fungicidal effect at 256 and 512 mg x L(-1). SEM results shows that 512 mg x L(-1) BAEB can inhibit the formation of C. tropicalis biofilm on Silicone catheter, and the morphology of biofilm is also affected by BAEB. The thickness of C. tropicalis biofilm is reduced by BAEB according to CLSM results. Furthermore, qRT-PCR results indicate that expression of UME6 and ALST3 are significantly down-regulated by BAEB 256,512 mg x L(-1), and NRG1 is not affected by BAEB.

CONCLUSIONBAEB inhibits effectively the CSH, filamentation and biofilm formation of VVC strains of C. tropicalis.

Antifungal Agents ; chemistry ; pharmacology ; Biofilms ; drug effects ; Candida tropicalis ; drug effects ; genetics ; physiology ; Candidiasis ; microbiology ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Fungal Proteins ; genetics ; metabolism ; Gene Expression Regulation, Fungal ; drug effects ; Humans ; Virulence Factors ; genetics ; metabolism

As a commensal or a pathogen, Helicobacter pylori can change the balance of a complex interaction that exists among gastric epithelial cells, microbes, and their environment. Therefore, unraveling this complex relationship of these mixtures can be expected to help prevent cancer as well as troublesome unmet medical needs of H. pylori infection. Though gastric carcinogenesis is a multi-step process, precancerous lesion can be reversible in the early phase of mucosal damage before reaching the stage of no return. However, biomarkers to predict rejuvenation of precancerous atrophic gastritis have not been identified yet and gastric cancer prevention is still regarded as an impregnable fortress. However, when we take the journey from H. pylori-associated gastritis to gastric cancer, it provides us with the clue for prevention since there are two main preventive strategies: eradication and anti-inflammation. The evidence supporting the former strategy is now ongoing in Japan through a nation-wide effort to eradicate H. pylori in patients with chronic gastritis, but suboptimal apprehension to increasing H. pylori resistance to antibiotics and patient non-compliance still exists. The latter strategy has been continued in the author's research center under siTRP (short-term intervention to revert premalignant lesion) strategy. By focusing on the role of inflammation in the development of H. pylori-associated gastric carcinogenesis, this review is intended to explain the connection between inflammation and gastric cancer. Strategies on H. pylori eradication, removal of inflammation, and reverting preneoplastic lesion will also be introduced. In the end, we expect to be able to prevent gastric cancer by take a detour from the unpleasant journey, i.e. from H. pylori-associated gastritis to gastric cancer.
Animals ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Biomarkers/metabolism ; Disease Models, Animal ; Gastritis/*etiology ; Helicobacter Infections/*complications/drug therapy ; Helicobacter pylori/drug effects/metabolism/physiology ; Humans ; Stomach Neoplasms/etiology/*prevention & control ; Virulence Factors/metabolism

OBJECTIVETo establish a protocol for the targeting gene therapy against cancer with rich epidermal growth factor receptor (EGFR).

METHODSA recombinant pcDNA3.1-PE III mut was constructed and combined with a non-viral vector, a fusion protein histone H1, epidermal growth factor C-loop previously expressed by us, to be a protein-DNA complex in vitro. Using the complex to treat BT-325 and Hela cancer cells with EGFR and JK cells without EGFR. The killing rates of the cells was calculated after 48 h of incubation at 37 degrees C.

RESULTSTo BT-325 and Hela cells, the killing rates were 46.03% and 48.12% respectively. To JK cells, the complex had no killing function.

CONCLUSIONThe protocol for targeting gene therapy against cancer with EGFR has been established successfully.

ADP Ribose Transferases ; genetics ; pharmacology ; Bacterial Toxins ; genetics ; pharmacology ; Base Sequence ; Cell Line, Tumor ; Cells ; DNA ; genetics ; Exotoxins ; genetics ; pharmacology ; Gene Targeting ; Genetic Therapy ; Genetic Vectors ; Histones ; genetics ; Humans ; Molecular Sequence Data ; Receptor, Epidermal Growth Factor ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; metabolism ; pharmacology ; Transfection ; Virulence Factors ; genetics ; pharmacology