Associations between the FAS ?670?A/G and ?1,377?G/A polymorphisms and susceptibility to autoimmune rheumatic diseases: a meta-analysis

The aim of this study was to explore whether FAS ?670?A/G and ?1,377?G/A polymorphisms confer susceptibility to autoimmune rheumatic diseases. A meta-analysis was conducted on the associations between the FAS ?670?A/G and ?1,377?G/A polymorphisms and autoimmune rheumatic diseases using allele contrast, a recessive model, a dominant model, and an additive model. Thirteen articles with 21 comparison studies (16 on FAS ?670?A/G and 5 on ?1,377?G/A polymorphisms) including systemic lupus erythematosus (SLE), four systemic sclerosis, four Sjogren’s syndrome, three rheumatoid arthritis (RA), one juvenile idiopathic arthritis, and one spondyloarthropathy were available for the meta-analysis. Meta-analysis revealed an association between rheumatic diseases and the FAS ?670?A/G polymorphism in the dominant model (odds ratio [OR]?=?0.761, 95?% confidence interval [CI]?=?0.621–0.932, p?=?0.008]. Stratification by ethnicity indicated an association between the FAS ?670?G allele carrier and rheumatic diseases in Asian (OR?=?0.569, 95?% CI?=?0.409–0.791, p?=?0.001). Furthermore, stratification by disease indicated an association between the FAS ?670?G allele carrier and SLE and RA (OR?=?0.578, 95?% CI?=?0.358–0.934, p?=?0.025; OR?=?0.609, 95?% CI?=?0.398–0.934, p?=?0.023, respectively). The FAS ?670?G allele was negatively associated with SLE susceptibility. Meta-analysis of the FAS ?1,377?G/A polymorphism stratified by disease showed an association between the FAS ?1,377 A allele and SLE (OR?=?0.783, 95?% CI?=?0.613–0.997, p?=?0.047). Meta-analyses using the dominant model also showed a significant association in SLE (OR?=?0.712, 95?% CI?=?0.528–0.961, p?=?0.027). This meta-analysis demonstrates that the FAS ?670?A/G polymorphism confers susceptibility to rheumatic diseases in Asians and SLE and RA, and the FAS ?1,377?G/A polymorphism is associated with SLE susceptibility.     

Pretreatment of acetylsalicylic acid promotes tumor necrosis factor-related apoptosis-inducing ligand-induced apoptosis by down-regulating BCL-2 gene expression

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been shown to be selective in the induction of apoptosis in cancer cells with minimal toxicity to normal tissues. However, not all cancers are sensitive to TRAIL-mediated apoptosis. Thus, TRAIL-resistant cancer cells must be sensitized first to become responsive to TRAIL. In this study, we observed that pretreatment by acetylsalicylic acid (ASA) augmented TRAIL-induced apoptotic death in human prostate adenocarcinoma LNCaP and human colorectal carcinoma CX-1 cells. Western blot analysis showed that pretreatment of ASA followed by TRAIL treatment activated caspases (8, 9, and 3) and cleaved poly(ADP-ribose) polymerase, the hallmark feature of apoptosis. Most interestingly, at least 12 h of pretreatment with ASA was prerequisite for promoting TRAIL-induced apoptosis and was related to down-regulation of BCL-2. Biochemical analysis revealed that ASA inhibited NF-kappaB activity, which is known to regulate BCL-2 gene expression, by dephosphorylating IkappaB-alpha and inhibiting IKKbeta activity but not by affecting the HER-2/neu phosphatidylinositol 3-kinase-Akt signal pathway. Overexpression of BCL-2 suppressed the promotive effect of ASA on TRAIL-induced apoptosis and changes in mitochondrial membrane potential. Taken together, our studies suggested that ASA-promoted TRAIL cytotoxicity is mediated through down-regulating BCL-2 and by decreasing mitochondrial membrane potential.     

Cyclosporine A Reduces Dendritic Outgrowth of Neuroblasts in the Subgranular Zone of the Dentate Gyrus in C57BL/6 Mice

In the present study, we observed the effects of cyclosporine A (CsA), an efficient immunosuppressant, on cell proliferation and neuroblast differentiation in the subgranular zone of the dentate gyrus (SZDG) in normal C57BL/6 mice using Ki67 and doublecortin (DCX) immunohistochemical staining, respectively. At 8 weeks of age, vehicle (physiological saline) or CsA was daily administered (40 mg/kg, i.p.) for 1 week. Animals were sacrificed at 2 weeks after last administration. CsA treatment did not show any influences in neurons, astrocytes and microglia based on immunohistochemistry for its markers, respectively. However, in the CsA-treated group, Fluoro-Jade B, a marker for neurodegeneration, positive cells were found in the SZDG, not in the vehicle-treated group. In the vehicle-treated group, Ki67 immunoreactive (⁺) nuclei were clustered in the SZDG, whereas in the CsA-treated group Ki67⁺ nuclei were scattered in the SZDG, showing no difference in cell numbers. Numbers of DCX⁺ neuroblasts with well-developed processes (tertiary dendrites) were much lower in the CsA-treated group than those in the vehicle-treated group; however, numbers of DCX⁺ neuroblasts with secondary dendrites were similar in both the groups. These results suggest that CsA significantly reduces dendritic outgrowth and complexity from neuroblasts in the SZDG without any affecting in neurons, astrocytes and microglia in normal mice.     

Self-assembled ternary complex of cationic dendrimer,cucurbituril, and DNA: noncovalent strategy in developing a gene delivery carrier

A ternary complex of PPI-DAB dendrimer [(1,4-diaminobutane); Gen = N; dendri-poly(propyleneimine); -[NHC(=O)CH(2)NH(2)(+)(CH(2))(4)NH(3)(+)](z)()], DNA, and cucurbituril (CB) was evaluated as an example of a totally self-assembled gene delivery carrier. The complex was formed in a noncovalent way in which DNA interacts with PPI-DAB electrostatistically and CB with PPI-DAB through multiple noncovalent interactions. Dynamic light scattering data indicated that the diameter and size distributions of the complexes were dependent upon the sequence of mixing of each component with unimodal distribution ranging from 150.8 to 210.2 nm under favorable conditions. Fluorescence studies showed the quantitative binding of CB to PPI-DAB after ternary complex formation. The complex was able to transfect mammalian cells with high efficiency and the cytotoxicity of the PPI-DAB/CB complex was relatively low.     

Allogeneic Human Mesenchymal Stem Cells Restore Epithelial Protein Permeability in Cultured Human Alveolar Type II Cells by Secretion of Angiopoietin-1

Acute lung injury is characterized by injury to the lung epithelium that leads to impaired resolution of pulmonary edema and also facilitates accumulation of protein-rich edema fluid and inflammatory cells in the distal airspaces of the lung. Recent in vivo and in vitro studies suggest that mesenchymal stem cells (MSC) may have therapeutic value for the treatment of acute lung injury. Here we tested the ability of human allogeneic mesenchymal stem cells to restore epithelial permeability to protein across primary cultures of polarized human alveolar epithelial type II cells after an inflammatory insult. Alveolar epithelial type II cells were grown on a Transwell plate with an air-liquid interface and injured by cytomix, a combination of IL-1β, TNFα, and IFNγ. Protein permeability measured by ¹³¹I-labeled albumin flux was increased by 5-fold over 24 h after cytokine-induced injury. Co-culture of human MSC restored type II cell epithelial permeability to protein to control levels. Using siRNA knockdown of potential paracrine soluble factors, we found that angiopoietin-1 secretion was responsible for this beneficial effect in part by preventing actin stress fiber formation and claudin 18 disorganization through suppression of NFκB activity. This study provides novel evidence for a beneficial effect of MSC on alveolar epithelial permeability to protein.     

Autophagy protein Rubicon mediates phagocytic NADPH oxidase activation in response to microbial infection or TLR stimulation

Phagocytosis and autophagy are two important and related arms of the host's first-line defense against microbial invasion. Rubicon is a RUN domain containing cysteine-rich protein that functions as part of a Beclin-1-Vps34-containing autophagy complex. We report that Rubicon is also an essential, positive regulator of the NADPH oxidase complex. Upon microbial infection or Toll-like-receptor 2 (TLR2) activation, Rubicon interacts with the p22phox subunit of the NADPH oxidase complex, facilitating its phagosomal trafficking to induce a burst of reactive oxygen species (ROS) and inflammatory cytokines. Consequently, ectopic expression or depletion of Rubicon profoundly affected ROS, inflammatory cytokine production, and subsequent antimicrobial activity. Rubicon's actions in autophagy and in the NADPH oxidase complex are functionally and genetically separable, indicating that Rubicon functions in two ancient innate immune machineries, autophagy and phagocytosis, depending on the environmental stimulus. Rubicon may thus be pivotal to generating an optimal intracellular immune response against microbial infection.     

Comparative study of two thioredoxin peroxidases from disk abalone (Haliotis discus discus): cloning, recombinant protein purification, characterization of antioxidant activities and expression analysis

Thioredoxin peroxidase (TPx), also named peroxiredoxin (Prx), is an important peroxidase, which can protect organisms against various oxidative stresses. Two TPxs were isolated from a disk abalone (Haliotis discus discus) cDNA library, named as AbTPx1 and AbTPx2, respectively. AbTPx1 and AbTPx2 consist of 1315 and 1045 bp full-length cDNA with 753 and 597 bp open reading frames encoding 251 and 199 amino acids, respectively. The TPx signature motif 1 (FYPLDFTFVCPTEI) and motif 2 (GEVCPA) were conserved in both AbTPx1 and AbTPx2 amino acid sequences. Purified recombinant abalone TPx fusion proteins catalyzed the reduction of H2O2 and butyl hydroperoxide in peroxidase assays. Furthermore, both AbTPx fusion proteins were shown to protect super-coiled DNA from damage by metal-catalyzed oxidation (MCO) in vitro. Escherichia coli cells transformed with AbTPx1 and AbTPx2 coding sequences in pMAL-c2x showed resistance to H2O2 at 0.8 mM concentration by in vivo H2O2 tolerance assay. AbTPx1 and AbTPx2 mRNA were constitutively expressed in gill, mantle, abductor muscle and digestive tract in a tissue specific manner. Additionally, both TPxs mRNA were up-regulated in gill and digestive tract tissues against H2O2 at 3h post injection. The results indicate that AbTPx1 and AbTPx2 gene expressions are induced by oxidative stress and their respective proteins function in the detoxification of different ROS molecules to maintain efficient antioxidant defense in disk abalone.     

N‐glycan maturation is crucial for cytokinin‐mediated development and cellulose synthesis in Oryza sativa

To explore the physiological significance of N‐glycan maturation in the plant Golgi apparatus, gnt1, a mutant with loss of N‐acetylglucosaminyltransferase I (GnTI) function, was isolated in Oryza sativa. gnt1 exhibited complete inhibition of N‐glycan maturation and accumulated high‐mannose N‐glycans. Phenotypic analyses revealed that gnt1 shows defective post‐seedling development and incomplete cell wall biosynthesis, leading to symptoms such as failure in tiller formation, brittle leaves, reduced cell wall thickness, and decreased cellulose content. The developmental defects of gnt1 ultimately resulted in early lethality without transition to the reproductive stage. However, callus induced from gnt1 seeds could be maintained for periods, although it exhibited a low proliferation rate, small size, and hypersensitivity to salt stress. Shoot regeneration and dark‐induced leaf senescence assays indicated that the loss of GnTI function results in reduced sensitivity to cytokinin in rice. Reduced expression of A‐type O. sativa response regulators that are rapidly induced by cytokinins in gnt1 confirmed that cytokinin signaling is impaired in the mutant. These results strongly support the proposed involvement of N‐glycan maturation in transport as well as in the function of membrane proteins that are synthesized via the endomembrane system.     

A nodule-specific dicarboxylate transporter from alder is a member of the peptide transporter family

Alder (Alnus glutinosa) and more than 200 angiosperms that encompass 24 genera are collectively called actinorhizal plants. These plants form a symbiotic relationship with the nitrogen-fixing actinomycete Frankia strain HFPArI3. The plants provide the bacteria with carbon sources in exchange for fixed nitrogen, but this metabolite exchange in actinorhizal nodules has not been well defined. We isolated an alder cDNA from a nodule cDNA library by differential screening with nodule versus root cDNA and found that it encoded a transporter of the PTR (peptide transporter) family, AgDCAT1. AgDCAT1 mRNA was detected only in the nodules and not in other plant organs. Immunolocalization analysis showed that AgDCAT1 protein is localized at the symbiotic interface. The AgDCAT1 substrate was determined by its heterologous expression in two systems. Xenopus laevis oocytes injected with AgDCAT1 cRNA showed an outward current when perfused with malate or succinate, and AgDCAT1 was able to complement a dicarboxylate uptake-deficient Escherichia coli mutant. Using the E. coli system, AgDCAT1 was shown to be a dicarboxylate transporter with a K(m) of 70 microm for malate. It also transported succinate, fumarate, and oxaloacetate. To our knowledge, AgDCAT1 is the first dicarboxylate transporter to be isolated from the nodules of symbiotic plants, and we suggest that it may supply the intracellular bacteria with dicarboxylates as carbon sources.