Anthocyanins from soybean seed coat inhibit the expression of TNF-alpha-induced genes associated with ischemia/reperfusion in endothelial cell by NF-kappaB-dependent pathway and reduce rat myocardial damages incurred by ischemia and reperfusion in vivo

We examined the inhibition of the expression of some inflammatory genes associated with ischemia-reperfusion (I/R) injury by anthocyanins isolated from black soybean seed coat in tumor necrosis factor-alpha (TNF-alpha)-treated bovine aortic endothelial cells. In addition, its potential use on I/R-injury was investigated using rats subjected to 30-min occlusion of left descending coronary artery followed by 24-h reperfusion. Western blot analysis and luciferase activity assay showed that anthocyanins inhibited TNF-alpha-induced vascular cell adhesion molecule-1, intracellular adhesion molecule-1, and cyclooxygenase-2 levels, which is through NF-kappaB-dependent pathway. Further, anthocyanins protected myocardiac injury from I/R in rats. It is suggested that anthocyanins from black soybean seed coat can be used as a useful drug to modulate cardiovascular disorder.     

Involvement of Na+/H+ exchanger in the calcium signaling in epimastigotes of Trypanosoma cruzi

We studied the effect of Na(+) extracellular on Ca(2+) mobilization from intracellular store evoked by carbachol in Trypanosoma cruzi. We report that slow component of Ca(2+) signaling evoked by agonist is dependent on extracellular Na(+) but not on InsP(3) increase. Moreover, this Ca(2+) signaling progressively increased when pH of the medium changed from 7.0 to 7.8. In addition, we found that it was regulated by PKC. The agonist was also able to induce the alkalinization of the acidic compartment, and both Ca(2+) signaling and alkalinization were inhibited by the EIPA-inhibitor of the Na(+)/H(+) exchanger. These results demonstrated the alkalinization of acidic vacuoles and PKC are involved in the triggering of the epimastigote Ca(2+) signaling.     

Neuroprotective Effect of A20 on TNF-Induced Postischemic Apoptosis

Focal cerebral ischemia causes apoptosis in neural cells during the postischemia period. TNF is critically involved in such neuronal apoptosis mediated by caspase pathways. A20 can inhibit TNF-induced apoptosis in many cell types. However, little work has been carried out in central nervous system. In the present study, gene transfer of A20 resulted in reduction of infarct volume and improvement of neurological deficit in ischemia rats. Results of flow cytometry, TUNEL and DNA fragmentation assay all indicated A20 could inhibit TNF-induced apoptosis both in primary rat hippocampal neurons and SH-SY5Y cells. Moreover, we found A20 targeted the TNF apoptotic pathway by inhibiting proteolytic cleavage of caspase 8 and 3 in SH-SY5Y cells. These data demonstrated A20 could effectively protect neurons from postischemic apoptosis and may function partly on death receptor caspase pathway. Gene transfer of A20 may be a promising approach to gene therapy for cerebral ischemia in the future. Luyang Yu and Hongsheng Miao - These two authors contribute equally to this work     

Mimotope vaccination for epitope-specific induction of anti-CD20 antibodies

CD20 is expressed strictly by B-cells and is ubiquitously expressed at high surface densities of malignant human B-cells. This suggests that CD20 may be a tumor target for immunotherapy of B-cell lymphomas. Rituximab, a chimeric monoclonal antibody directed against CD20, has been demonstrated to be an effective treatment for non-Hodgkin's lymphoma (NHL) and some autoimmune diseases. In the current study, we used the phage display technique to generate mimotopes that complemented the screening Ab Rituximab. A total of seven candidate mimotopes were isolated from a 12-mer peptide library from which one mimotope was conjugated to keyhole limpet hemocyanin (KLH) or tetanus toxoid (TT). The immunogenicity of the two vaccines generated was examined in BALB/c mice. Sera from the vaccinated mice demonstrated high-titer specific antibodies to the mimotope conjugates. Antibody binding to native CD20 and Ab-mediated cytotoxicity (CDC, complement-dependent cytotoxicity) were also analyzed. Our data suggest that a Rituximab mimotope may be a useful tool for the construction of a functional vaccine to treat B-cell malignancy as well as some CD20 related autoimmune disorders.     

Cell differentiation dependent expressed CCR6 mediates ERK-1/2, SAPK/JNK, and Akt signaling resulting in proliferation and migration of colorectal cancer cells

The expression of CCL20 (MIP-3alpha), which chemoattracts leukocytes to sites of inflammation, has been shown in intestinal epithelial cells (IEC). Aim of this study was to analyze the role of the CCL20 receptor CCR6 in IEC and colorectal cancer (CRC) cells. Expression of CCR6 and CCL20 was analyzed by RT-PCR and immunohistochemistry. Signaling was investigated by Western blotting, proliferation by MTS assays and chemotactic cell migration by wounding assays. The effect of CCL20 on Fas-induced apoptosis was determined by flow cytometry. CCR6 and its ligand CCL20 are expressed in IEC. Moreover, CRC and CRC metastases express CCR6, which is upregulated during IEC differentiation. Stimulation of IEC with CCL20 and proinflammatory stimuli (TNF-alpha, IL-1beta, LPS) significantly upregulates CCL20 mRNA expression. CCL20 expression was significantly increased in inflamed colonic lesions in Crohn's disease and correlated significantly with the IL-8 mRNA expression in these lesions (r = 0.71) but was downregulated in CRC metastases. CCL20 activated Akt, ERK-1/2, and SAPK/JNK MAP kinases and increased IL-8 protein expression. The CCL20 mediated activation of these pathways resulted in a 2.6-fold increase of cell migration (P = 0.001) and in a significant increase of cell proliferation (P < 0.05) but did not influence Fas-induced apoptosis. In conclusion, IEC and CRC express CCL20 and its receptor CCR6. CCL20 expression is increased in intestinal inflammation, while CCR6 is upregulated during cell differentiation. CCR6 mediated signals result in increased IEC migration and proliferation suggesting an important role in intestinal homeostasis and intestinal inflammation by mediating chemotaxis of IEC but also in mediating migration of CRC cells.     

A structured-population model of Proteus mirabilis swarm-colony development

In this paper we present continuous age- and space-structured models and numerical computations of Proteus mirabilis swarm-colony development. We base the mathematical representation of the cell-cycle dynamics of Proteus mirabilis on those developed by Esipov and Shapiro, which are the best understood aspects of the system, and we make minimum assumptions about less-understood mechanisms, such as precise forms of the spatial diffusion. The models in this paper have explicit age-structure and, when solved numerically, display both the temporal and spatial regularity seen in experiments, whereas the Esipov and Shapiro model, when solved accurately, shows only the temporal regularity. The composite hyperbolic-parabolic partial differential equations used to model Proteus mirabilis swarm-colony development are relevant to other biological systems where the spatial dynamics depend on local physiological structure. We use computational methods designed for such systems, with known convergence properties, to obtain the numerical results presented in this paper.     

The crystal structure of the C-terminal domain of Vps28 reveals a conserved surface required for Vps20 recruitment

The endosomal sorting complex I required for transport (ESCRT-I) is composed of the three subunits Vps23/Tsg101, Vps28 and Vps37. ESCRT-I is recruited to cellular membranes during multivesicular endosome biogenesis and by enveloped viruses such as HIV-1 to mediate budding from the cell. Here, we describe the crystal structure of a conserved C-terminal domain from Sacharomyces cerevisiae Vps28 (Vps28-CTD) at 3.05 A resolution which folds independently into a four-helical bundle structure. Co-expression experiments of Vps28-CTD, Vps23 and Vps37 suggest that Vps28-CTD does not directly participate in ESCRT-I assembly and may thus act as an adaptor module for downstream interaction partners. We show through mutagenesis studies that Vps28-CTD employs its strictly conserved surface in the interaction with the ESCRT-III factor Vps20. Furthermore, we present evidence that Vps28-CTD is sufficient to rescue an equine infectious anaemia virus (EIAV) Gag late domain deletion. Vps28-CTD mutations abolishing Vps20 interaction in vitro also prevent the rescue of the EIAV Gag late domain mutant consistent with a potential direct Vps28-ESCRT-III Vps20 recruitment. Therefore, the physiological relevant EIAV Gag-Alix interaction can be functionally replaced by a Gag-Vps28-CTD fusion. Because both Alix and Vps28-CTD can directly recruit ESCRT-III proteins, ESCRT-III assembly coupled to Vps4 action may therefore constitute the minimal budding machinery for EIAV release.     

An efficient route from trifluoroacetates to water soluble free amines using Diaion® HP-20

A series of polybasic lysine and ornithine derivatives were synthesised as trifluoroacetate salts. Attempts to prepare their free amines according to standard methodology were not successful due to the excellent water solubility of these compounds. Free amines were however efficiently obtained if the column with Diaion HP-20 adsorbent was loaded with the trifluoroacetate and 1% NaHCO(3) aq was passed, followed by elution of free amine with methanol.