Improving endothelial cell junction integrity by diphenylmethanone derivatives at oxidative stress: A dual-action directly targeting caveolar caveolin-1.

Directly targeting caveolar caveolin-1 is a potential mechanism to regulate endothelial permeability, especially during oxidative stress, but little evidence on the topic limits therapeutics discoveries. In this study, we investigated the pharmacological effect of an antioxidant LM49 (5,2'-dibromo-2,4',5'-trihydroxydiphenylmethanoe) and its five diphenylmethanone derivatives on endothelial permeability and establish two distinct mechanisms of action. Multiplex molecular assays with theoretical modeling indicate that diphenylmethanone molecules, including LM49, directly bind the caveolin-1 steric pocket of ASN53/ARG54, ILE49/ASP50, ILE18, LEU59, ASN60, GLU48 and ARG19 residues. They also indicated dynamic binding-affinity for diphenylmethanone derivatives. First, this molecular interaction at caveolin-1 pocket inhibits its phosphorylation at TYR14 residue in H2O2-injured endothelial cell. A positive correlation was established between diphenylmethanone derivative binding-affinity and caveolin-1 phosphorylation inhibition. Inhibition of caveolin-1 phosphorylation, however, was independent of the LM49-mediated variation of protein tyrosine kinase activity, suggesting a direct blockage of adenosine triphosphate substrate diffusion into cavelion-1 structure. Second, LM49 increases the expression of cellular adhesive and tight junction proteins, VE-cadherin and occludin, in H2O2-injured cell, in a dose dependent manner. A leakage assay of fluorescein isothiocyanate-labeled dextran 40 across cell monolayer suggested improvement in endothelial barrier integrity with diphenylmethanone treatments. Our results demonstrate a direct targeting effect of caveolin-1 on endothelial permeability, and should guide the diphenylmethanone therapy against oxidative stress-induced junction dysfunction, especially at caveolar membrane invagination.

5,2'-dibromo-2,4',5'-trihydroxydiphenylmethanone attenuates LPS-induced inflammation and ROS production in EA.hy926 cells via HMBOX1 induction.

Inflammation and reactive oxygen species (ROS) are important factors in the pathogenesis of atherosclerosis (AS). 5,2'-dibromo-2,4',5'-trihydroxydiphenylmethanone (TDD), possess anti-atherogenic properties; however, its underlying mechanism of action remains unclear. Therefore, we sought to understand the therapeutic molecular mechanism of TDD in inflammatory response and oxidative stress in EA.hy926 cells. Microarray analysis revealed that the expression of homeobox containing 1 (HMBOX1) was dramatically upregulated in TDD-treated EA.hy926 cells. According to the gene ontology (GO) analysis of microarray data, TDD significantly influenced the response to lipopolysaccharide (LPS); it suppressed the LPS-induced adhesion of monocytes to EA.hy926 cells. Simultaneously, TDD dose-dependently inhibited the production or expression of IL-6, IL-1ß, MCP-1, TNF-α, VCAM-1, ICAM-1 and E-selectin as well as ROS in LPS-stimulated EA.hy926 cells. HMBOX1 knockdown using RNA interference attenuated the anti-inflammatory and anti-oxidative effects of TDD. Furthermore, TDD inhibited LPS-induced NF-κB and MAPK activation in EA.hy926 cells, but this effect was abolished by HMBOX1 knockdown. Overall, these results demonstrate that TDD activates HMBOX1, which is an inducible protective mechanism that inhibits LPS-induced inflammation and ROS production in EA.hy926 cells by the subsequent inhibition of redox-sensitive NF-κB and MAPK activation. Our study suggested that TDD may be a potential novel agent for treating endothelial cells dysfunction in AS.

Hypothetical protein Cpn0423 triggers NOD2 activation and contributes to Chlamydia pneumoniae-mediated inflammation.

BACKGROUND: Chlamydia pneumoniae (C. pneumoniae) is pathogenic to humans, by causing pulmonary inflammation or bronchitis in both adolescents and young adults. However, the molecular signals linking C. pneumoniae components to inflammation remain elusive. This study was to investigate the effect of Chlamydia-specific Cpn0423 of C. pneumoniae on C. pneumoniae-mediated inflammation. RESULTS: Cpn0423 was detected outside of C. pneumoniae inclusions, which induced production of several cytokines including macrophage inflammatory protein-2 (MIP-2) and interleukins (ILs). Production of the Cpn0423-induced cytokines was markedly reduced in cells pretreated with NOD2-siRNA, but not with negative control oligonucleotides. Mice treated with Cpn0423 through intranasal administration exhibited pulmonary inflammation as evidenced by infiltration of inflammatory cells, increased inflammatory scores in the lung histology, recruitment of neutrophils and increased cytokines levels in the BALF. CONCLUSION: Cpn0423 could be sensed by NOD2, which was identified as an essential element in a pathway contributing to the development of C. pneumoniae -mediated inflammation.

Electrochemical behavior and voltammetric determination of norfloxacin at glassy carbon electrode modified with multi walled carbon nanotubes/Nafion.

A simple and rapid electrochemical method is developed for the determination of trace-level norfloxacin, based on the excellent properties of multi-walled carbon nanotubes (MWCNTs). The MWCNTs/Nafion film-coated glassy carbon electrode (GCE) is constructed and the electrochemical behavior of norfloxacin at the electrode is investigated in detail. The results indicate that MWCNTs modified glassy carbon electrode exhibited efficiently electrocatalytic oxidation for norfloxacin (NFX) with relatively high sensitivity, stability and life time. Under conditions of cyclic voltammetry, the current for oxidation of selected analyte is enhanced significantly in comparison to the bare GCE. The electrocatalytic behavior is further exploited as a sensitive detection scheme for the analyte determinations by linear sweep voltammetry (LSV). Under optimized condition in voltammetric method the concentration calibration range and detection limit (S/N=3) are 0.1-100 micromol/L and 5 x 10(-8)mol/L for NFX. The proposed method was successfully applied to NFX determination in tablets. The analytical performance of this sensor has been evaluated for detection of the analyte in urine as a real sample.

[Gene Polymorphism of Inflammation-related Cytokines Correlates with the Susceptibility to DLBCL].

OBJECTIVE: To investigate the relationship of gene polymorphisms of inflammattion related cytokines with incidence of diffuse large B-cell lymphoma(DLBCL) in Gansu Han population. METHODS: The gene polymorphism of inflammation-related cytokines were detected by high-resolution melting(HRM) curve. RESULTS: The homozygous CC genotype carrying IL-1RA rs4251961 gene locus was related with the risk of DLBCL in comparison with homozygous TT, the OR was 0.83 of homozygous CC, 95% CI=0.697-0.997,P<0.05), while the C allele of IL-1RA rs4251961 gene locus significantly correlated with the high incidence of diffuse large B-cell lymphoma compared with T allele(OR=8.83, 95% CI=1.909-40.813,P<0.01). CONCLUSION: The minor allele C of IL-1RA rs4251961 gene locus significantly relates with the susceptibility to DLBCL.

[Roles of IL-4, IL-5 and IgE in childhood cough variant asthma].

OBJECTIVE: To study the roles of IL-4, IL-5 and IgE in childhood cough variant asthma (CVA). METHODS: The IL-4 and IL-5 levels in peripheral blood mononuclear cell (PBMC) and the serum IgE levels were determined using ELISA in children with CVA in the acute stage (n=21) and in the convalesce stage (n=9). The samples from 30 children with acute bronchial asthma and from 30 healthy children were used as controls. RESULTS: The levels of PBMC IL-4 (91.57 +/- 12.19 ng/L) and IL-5 (13.28 +/- 0.31 ng/mL) in children with CVA in the acute stage were significantly higher than those in the convalesce stage (74.68 +/- 11.54 ng/L, 6.53 +/- 0.28 ng/mL) and also higher than those in the healthy controls (70.32 +/- 18.16 ng/L, 5.29 +/- 0.36 ng/mL) (P < 0.01). The levels of serum IgE in children with CVA in the acute stage (279.6 +/- 41.3 KU /L) were strikingly higher than those in the convalesce stage (153.8 +/- 37.5 KU/L) (P < 0.01). The levels of serum IgE in children with CVA either in the acute stage or in the convalesce stage were significantly higher than those in healthy controls (90.6 +/- 44.8 KU /L) (P < 0.01). There were no significant differences in the levels of IL-4, IL-5 and IgE between children with acute CVA and acute asthma. CONCLUSIONS: A combined determination of PBMC IL-4 and IL-5 and serum IgE may be valuable for the diagnosis and the outcome evaluation of CVA. IL-4 and IL-5 may play a role in the pathogenesis of CVA. It is speculated that CVA may have similar pathogenesis to bronchial asthma since acute CVA patients have similar IL-4, IL-5 and IgE levels to children with acute bronchial asthma.

Reproductive toxicity effects of 4-nonylphenol with known endocrine disrupting effects and induction of vitellogenin gene expression in silkworm, Bombyx mori.

4-Nonylphenol (4-NP) a known endocrine disrupting chemical is a persistent environmental contaminant. However, the mechanism of reproductive toxicity caused by 4-NP is still largely unresolved in invertebrates. In this study, Bombyx mori larvae were constantly fed 4-NP at concentrations ranging from 0.05 to 0.4gkg(-1), reproductive toxicity and induction of vitellogenin gene (Vg) expression were investigated in this organism which is an ideal lepidopteran model insect. The results showed that gonad development was retarded and maturity was decreased in both male and female pupae, while the sex ratio was unaffected by 4-NP exposure. In the 4-NP exposed animals, the corresponding egg yolk protein, vitellin, involved in energy reserves for embryonic development in oviparous animals, was present in the testis of male pupae, and the mRNA transcript of the Vg gene was detected in the fat body, a specific organ of Vg synthesis, which is normally silent in males. In addition, expression of the Vg gene was up-regulated in the fat body of female pupae and adults, while the protein was decreased in developing eggs. Furthermore, expression of the ecdysone receptor gene (EcR) in the ovaries of pupae was down-regulated, suggested that the transport of Vg from the fat body to developing oocytes was disturbed by 4-NP due to interference in the expression of EcR related to ecdysone activity.

Development of the fingerprints for the quality evaluation of Viscum coloratum by high Performance liquid chromatography.

A high-Performance liquid chromatography coupled ultraviolet (HPLC-UV) method was developed for a chemical fingerprint analysis of Viscum coloratum. Eighteen peaks were selected as the common peaks and Homoeriodictyol-7-0-ß-D-apiosiyl-(1→2)-ß-D-glucoside was used as a reference. The relative areas of common peaks were used for hierarchical clustering analysis and similarity calculation. Thirty-seven samples collected from different sources were classified into five groups. The similarities of 21 batches Viscum coloratum samples were beyond 0.90. The results obtained suggest that the Chromatographie fingerprint can efficiently identify Viscum coloratum. Additionally, the fingerprints can then be used to evaluate the correlation between Viscum coloratum and hosts.