Galangin ameliorated pulmonary fibrosis in vivo and in vitro by regulating epithelial-mesenchymal transition

Pulmonary fibrosis (PF) is a disease that is characterized by abnormal epithelial-mesenchymal transition (EMT) and persistent inflammatory injury, with high mortality and poor prognosis, but the current therapies are accompanied by certain adverse side effects. In this study, we investigated the role of galangin (GA), an anti-inflammatory and anti-tumoral phytochemical extracted from galangal, in preventing and curing bleomycin (BLM)-induced pulmonary fibrosis and the underlying mechanism. Histopathological staining confirmed that GA dramatically moderated bleomycin-induced pulmonary fibrosis in mice. Compared with the vehicle treatment, GA treatment inhibited the expression of vimentin and increased the expression of E-cadherin. The expression of α-Smooth muscle actin (α-SMA), which is a myofibroblast marker, was also suppressed. In addition, GA diminished the increase in the numbers of CD4⁺CD69⁺ and CD8⁺CD69⁺ T cells and dendritic cells induced by bleomycin, and reduced the residence of inflammatory cells in the lung tissues. Notably, GA inhibited the TGF-β1-induced EMT and fibroblast differentiation in vitro, which further confirmed the potential protective effect of GA on pulmonary fibrosis. Taken together, our results suggest that GA exerts a beneficial effect on bleomycin-induced pulmonary fibrosis by attenuating EMT and inflammatory damage and may have prevent potential of pulmonary fibrosis.     

Reversed isoniazids: Design,synthesis and evaluation against Mycobacterium tuberculosis

Novel reversed isoniazid (RINH) agents were synthesized by covalently linking isoniazid with various efflux pump inhibitor (EPI) cores and their structural motifs. These RINH agents were then evaluated for anti-mycobacterial activity against sensitive, isoniazid mono-resistant and MDR clinical isolates of M. tuberculosis and a selected number of compounds were also tested ex vivo for intracellular activity as well as in the ethidium bromide (EB) assay for efflux pump inhibition efficacy. The potency of some compounds against various strains of M. tuberculosis (4a–c, 7 and 8; H37Rv-MIC₉₉ ≤1.25?µM, R5401-MIC₉₉ ≤2.5?µM, X_61-MIC₉₉ ≤5?µM) demonstrated the potential of the reversed anti-TB agent strategy towards the development of novel anti-mycobacterial agents to address the rapidly growing issue of resistance. Further, macrophage activity with >90% inhibition by 1a–c and 3b (MIC₉₀ ≤13.42?µM) and inhibition of EB efflux demonstrated by these compounds are encouraging.     

Structural characterization of BVU_3255, a methyltransferase from human intestine antibiotic resistant pathogen Bacteroides vulgatus

Methylation is important for various cellular activities. To date, there is no report of any methyltransferase structure from the human intestine antibiotic resistant pathogen Bacteroides vulgatus. The protein BVU_3255 from B. vulgatus ATCC 8482 belongs to a SAM-dependent methyltransferase. Here, we report the crystal structure of apo BVU_3255, and its complexes with SAM and SAH, which revealed a typical class I Rossmann Fold Methyltransferase. Isothermal titration calorimetric studies showed that both SAM and SAH bind with equal affinity. The structural and sequence analysis suggested that BVU_3255 is a small molecule methyltransferase and involved in methylating the intermediates in ubiquinone biosynthesis pathway.     

Differential effects of glucose deprivation on the cellular sensitivity towards photodynamic treatment-based production of reactive oxygen species and apoptosis-induction

Photodynamic treatment (PDT) employs a photosensitizer and the light-induced formation of reactive oxygen species--antagonized by cellular antioxidant systems--for the removal of harmful cells. This study addresses the effect of altered carbohydrate metabolism on the cellular antioxidant glutathione system, and the subsequent responses to PDT. It is shown that glucose-deprivation of 18 h prior to PDT causes a reduced level of intracellular glutathione and an increased cytotoxicity of PDT. These effects can be mimicked by inhibitors of glutathione synthesis (buthionine-sulfoximine) or its regeneration (1,3-bis-(2-chlorethyl)-1-nitrosourea). Inhibited glutathione metabolism shifts the apoptotic window to lower fluences, while glucose deprivation abolishes apoptosis as a result of ATP deficiency. Our results prove evidence for manipulation of the outcome of PDT through internal metabolic pathways.     

Four‐Compartment Cellular Level Body Composition Model: Comparison of Two Approaches**

Objective: The aim of this study was to develop and compare two DXA‐based four‐compartment [body weight = body cell mass (BCM) + extracellular fluid (ECF) + extracellular solids (ECS) + fat] cellular level models. Research Methods and Procedures: Total body potassium (TBK) model: BCM from TBK by whole‐body counting—ECF_TBK = LST ? [BCM_TBK + 0.73 × osseous mineral (Mo)]. Bromide model: ECF from sodium bromide dilution—BCM_BROMIDE = LST ? (ECF_BROMIDE + 0.73 × Mo); Mo and LST measurements came from DXA. The two approaches were evaluated in 99 healthy men and 118 women. Results: BCM estimates were highly correlated (r = 0.97, p < 0.001), as were ECF estimates (r = 0.87, p < 0.001); a small statistically significant mean difference was present (mean ± SD; BCM_TBK model, 30.4 ± 8.9 kg; BCM_BROMIDE, 31.4 ± 9.3 kg; Δ = 1.0 ± 2.8 kg; p < 0.001; ECF_TBK, 18.5 ± 4.2 kg; ECF_BROMIDE, 17.5 ± 3.6 kg; Δ = 1.0 ± 2.8 kg; p < 0.001). A high correlation (r = 0.97, p < 0.001) and good agreement (38.9 ± 9.5 vs. 38.9 ± 9.5 kg; Δ = 0.0 ± 2.4 kg; p = 0.39) were present between TBW, derived as the sum of intracellular water from TBK and ECW from bromide, and measured TBW by ²H₂O dilution. Discussion: Two developed four‐compartment cellular level DXA models, one of which is appropriate for use in most clinical and research settings, provide comparable results and are applicable for BCM and ECF estimation of subject groups with hydration disturbances.     

Isolation of a human tissue-type plasminogen-activator genomic DNA clone and its expression in mouse L cells

We have isolated a cDNA clone corresponding to a substantial portion of the human tissue-type plasminogen activator (t-PA) protein. It encodes almost all of the protein B chain and part of the 3' untranslated region. We have used this clone to screen bacteriophage lambda and cosmid libraries of human genomic DNA. Several related genomic clones were isolated. One of these, a cosmid clone, carried approx. 40 kb of human DNA. Mapping experiments indicate that the region containing the protein-coding exons is approx. 20 kb in length. The cosmid, containing the t-PA gene and the aminoglycosyl-3'-phosphotransferase dominant-selection marker, was introduced into mouse L cells. Approximately half of the transformants were shown to produce human t-PA. We demonstrated that the fibrinolytic t-PA activity could be specifically quenched by anti-t-PA antibody and that the recombinant t-PA was of similar size (by SDS-polyacrylamide gel electrophoresis) to the t-PA produced by the human Bowes melanoma cell line. Our results suggest that the cosmid clone carries the whole t-PA coding region together with the regulatory elements necessary for its expression.     

Light increases the ion and non-electrolyte permeability of rhodopsin-phospholipid vesicles.

Rhodopsin-phospholipid vesicles were formed and loaded with radioactive markers by sonication. Exposure of the vesicles to light increased the permeability to Na⁺, Cs⁺, Ca²⁺, glycerol and glucose, but not to Cl^?, sucrose and inulin. These results indicate that light induces the formation of a wide permeability pathway with an apparent cut-off diameter of about 10Å.     

Cimetidine enhances immune response of HBV DNA vaccination via impairment of the regulatory function of regulatory T cells

Cimetidine (CIM), a histamine 2-receptor antagonist, is postulated to enhance immune responses owing to its inhibitory effects on suppressor T cells. In this report, we evaluated effects of cimetidine on the potency of antigen-specific immunity generated by DNA vaccine encoding hepatitis B surface antigen (HBsAg, pcD-S2). Our data demonstrate that CIM as adjuvant significantly increased HBsAg-specific cell-mediated and humoral immunities that were characterized by higher Ig2a/IgG1 ratio. In addition, CIM significantly promotes an elevated level of IL-4 and IFN-γ in antigen-specific CD4⁺ T cells and a robust antigen-specific cytotoxic response in the animals immunized with pcD-S2 plus CIM. Further, CIM induces pro-inflammatory cytokine expression such as the IL-12 and down-regulates anti-inflammatory cytokine expression such as IL-10 and TGF-β, which may lead to an impairment of CD4⁺CD25⁺ Treg cell-mediated suppression. Collectively these findings suggest that CIM enhances the immune responses of HBV DNA vaccine through the stimulation of pro-inflammatory and inhibition of anti-inflammatory cytokine expression patterns.     

Attenuated cytotoxicity but enhanced betafibril of a mutant amyloid beta-peptide with a methionine to cysteine substitution

Amyloid-beta peptide (Abeta), the major constituent of senile plaques in the Alzheimer's disease (AD) brain, is the main source of oxidative stress leading to neurodegeneration. The methionine residue in this peptide is reported to be responsible for neurotoxicity. Structurally similar substitution with methionine 35 replaced by cysteine in Abeta(40) was synthesized, and this result in enhanced beta-sheet structures according to both circular dichroism (CD) spectra and beta-fibril specific fluorescence assay but attenuated cytotoxicity whether in the presence of copper or not. These findings may provide further evidence on disclosing the connection between amyloid beta-aggregation and Abeta-induced neurotoxicity.