Helicobacter pylori-induced REDD1 modulates Th17 cell responses that contribute to gastritis.

OBJECTIVE: Regulated in development and DNA damage responses-1 (REDD1) is a conserved and ubiquitous protein, which is induced in response to multiple stimuli. However, the regulation, function and clinical relevance of REDD1 in Helicobacter pylori-associated gastritis are presently unknown. APPROACH: Immunohistochemistry, real-time PCR and Western blot analyses were performed to examine the levels of REDD1 in gastric samples from H. pylori-infected patients and mice. Gastric tissues from Redd1-/- and wildtype (WT, control) mice were examined for inflammation. Gastric epithelial cells (GECs), monocytes and T cells were isolated, stimulated and/or cultured for REDD1 regulation and functional assays. RESULTS: REDD1 was increased in gastric mucosa of H. pylori-infected patients and mice. H. pylori induced GECs to express REDD1 via the phosphorylated cytotoxin associated gene A (cagA) that activated MAPKp38 pathway to mediate NF-κB directly binding to REDD1 promoter. Human gastric REDD1 increased with the severity of gastritis, and mouse REDD1 from non-marrow chimera-derived cells promoted gastric inflammation that was characterized by the influx of MHCII+ monocytes. Importantly, gastric inflammation, MHCII+ monocyte infiltration, IL-23 and IL-17A were attenuated in Redd1-/- mice. Mechanistically, REDD1 in GECs regulated CXCL1 production, which attracted MHCII+ monocytes migration by CXCL1-CXCR2 axis. Then H. pylori induced MHCII+ monocytes to secrete IL-23, which favored IL-17A-producing CD4+ cell (Th17 cell) polarization, thereby contributing to the development of H. pylori-associated gastritis. CONCLUSIONS: The present study identifies a novel regulatory network involving REDD1, which collectively exert a pro-inflammatory effect within gastric microenvironment. Efforts to inhibit this REDD1-dependent pathway may prove valuable strategies in treating of H. pylori-associated gastritis.

Differences of brain pathological changes and cognitive function after bilateral common carotid artery occlusion between Sprague-Dawley and Wistar rats / 生理学报

The aim of the present study was to investigate the differences of the pathological changes and cognitive function after bilateral common carotid artery occlusion (BCCAO) between Sprague-Dawley (SD) and Wistar rats. Male SD and Wistar rats were randomly divided into 2 groups, respectively: sham operated (S-sham and W-sham) and operated (S-BCCAO and W-BCCAO) groups. The survival rate and the rate of loss of pupillary light reflex (PLR) were observed on day 1, 3, 7, 14 and 28 after the operation, and the light-dark box, Y-maze and odor recognition tests were performed to detect cognitive function on day 28 after the operation. HE and Luxol fast blue staining were used to observe the pathological changes of gray matter (hippocampus), white matter (optical tract), optic nerve, and retina. The results showed that the survival rate of the W-BCCAO group was 62.5%, and PLR loss rate was 100%; whereas the survival rate of the S-BCCAO group was 100%, and PLR loss rate was 58.3%. In the W-BCCAO group, percentages of time spent and distance traveled in the light box were more than those in the W-sham group, but there was no statistical significance between the S-BCCAO and S-sham groups. In the S-BCCAO group, the percentages of time spent and distance traveled in the III arm (labyrinth arm) of the Y-maze were less than those in the S-sham group, but no statistical significance was found between the W-BCCAO group and W-sham group. In the S-BCCAO group, the discrimination ratio of the odor recognition task was less than that in the S-sham group, but no statistical significance could be seen between the W-BCCAO and W-sham groups. Ischemic injury was observed in the CA1 area of the hippocampus in the S-BCCAO group, but no readily visible damage was observed in the W-BCCAO group. Ischemic injury of the visual beam and optic nerve was observed in both the S-BCCAO and W-BCCAO groups. Compared with the corresponding sham groups, the S-BCCAO and W-BCCAO groups showed serious retinal damage with significant thinner retina. The ganglion cell layer (GCL), inner plexiform layer (IPL), and outer plexiform layer (OPL) were thinner in the S-BCCAO group, but no statistical significances were shown in the other layers. All the layers, except the outer nuclear layer (ONL), were significantly thinner in the W-BCCAO group. The results indicate that there are differences of the pathological changes in the hippocampus and visual conduction pathway after BCCAO between SD and Wistar rats, and the degree of learning and memory injury was also different, which suggests that the vascular dementia model of different rat strains should be selected according to research purpose.

The role of lipooligosaccharide in the biological activity of Moraxella bovis strains Epp63, Mb25 and L183/2, and isolation of capsular polysaccharide from L183/2.

The Gram-negative bovine pathogen Moraxella bovis is a causative agent of Infectious bovine keratoconjunctivitis, 'pink-eye' that affects cattle. Here we report that strain L183/2 has the same capsular polysaccharide (CPS) of unsulfated chondroitin, as does strain Mb25, whereas strain Epp63 does not express CPS. NMR analysis of the oligosaccharides (OS) derived from the lipooligosaccharides (LOS) in these three strains by NMR has shown that strain Mb25 and Epp63 have the same OS structure with a terminal N-acetylgalactosamine ((1S)-GalaNAc) residue →4,6-linked. Strain L183/2 lacks the (1 S)-GalaNAc residue. The biological role of M. bovis LOS was assessed by comparing the LOS from strains Epp63, Mb25 and L183/2 and truncated Epp63 LOS variants. LOS truncation affected M. bovis growth rate, susceptibility to antibiotics, detergents, bovine serum bactericidal activity, endotoxicity and adherence to HeLa cells.

Comparison of CTA and CTPa in diagnosis of cerebral vascular stenosis and occlusive diseases / 实用放射学杂志

Objective The original data of CT perfusion(CTP) using 320-row area detector can reconstruct the whole-brain dynamic CT perfusion-derived angiography (CTPa).To confirm whether CTPa could replace CTA in diagnosis of cerebral vascular stenosis and occlusive diseases.Methods Thirty-five patients undergoing CTA and CTPa were screened retrospectively for this study.The image quality,display of fine intracranial vascular,vascular enhancement CT value,SNR and CNR were compared from the same patient.Using DSA imaging as the golden standard,the Sn and Sp for detecting the vessel segments stenosis ≥50％ or occlusion were compared for two examinations.Results CTPa showed higher image quality score,vascular enhancement CT value,SNR and CNR than CTA (P＜0.001).CTPa was superior to CTA in the display of fine intracranial vascular.The Sn and Sp for detecting the vessel segments stenosis ≥50％ or occlusion were 88.57％ and 99.26％ with CTA,91.42％ and 99.75％ with CTPa respectively(P＞ 0.05).Conclusion Compared with CTA,CTPa provides better image quality and comparable vascular pathology.CTPa is expected to replace CTA in diagnosis of cerebral vascular stenosis and occlusive diseases.

Influences of sulfated polysaccharide from pine (Pinus massoniana) pollen on the regulation of [ Ca2+] i in T lymphocytes / 中国药理学通报

Aim Tostudytheinfluencesofsulfated polysaccharides ( SPPM60-D) on the regulation of free calcium concentration ( [ Ca2+] i ) of T lymphocytes of mice in vitro and explore the mechanisms involved. Methods Polysaccharides(PPM60)wereextracted from masson pine pollen with hot water and 60% etha-nol. PPM60-D was separated and purified from PPM60 with Sephacryl S-400HR. Sulfated polysaccharides ( SPPM60-D ) were derivated by chlorosulfonic acid-pyridine method and the [ Ca2+] i of T lymphocytes were measured by fluorescence spectrophotometer. IL-2 and IL-4 were measured by ELISA kits. Results ConAandSPPM60-Dcouldincrease[Ca2+]iinT lymphocytes by 211. 5% and 201. 8% respectively ( P<0. 01). 2-APB, LY294002, U73122 and verapamil rather than TAK-242 could significantly inhibit the in-crease of [ Ca2+] i induced by SPPM60-D. SPPM60-D could significantly increase the level of IL-2 and IL-4 in supernatant ( P <0. 01 ) . 2-APB rather than TAK-242 could significantly inhibit the increase of cyto-kines.Conclusion ItisspeculatedthatSPPM60-D could increase [ Ca2+ ] i via TCR/CD3-PI3K-PLC-IP3 R-Ca2+ signal pathway through TCD/CD3 receptor in T lymphocytes so that it could improve the level of IL-2 and IL-4 in supernatant in T lymphocytes.

Comparative study on bio-activity of polysaccharide from Pinus massoniana pollen and its sulfated derivative / 中国生化药物杂志

Purpose To study the polysaccharide from Pinus massoniana pollen(PPM)and to compare its anti-tumor,immune modulation activities and scavenging qualities of free radical with its sulfated derivative(S-PPM).Methods PPM Wag chemically modified by chlorosulfonic acid-pyfidine method and their bioactivities were compared.Results The substituting degree of S-PPM was 1.47.Results showed that S-PPM was more powerful in inhibiting the growth of tumor cell in vivo and in vitro and in promoting T,B lymphocytes than PPM.But there Wag no remarkable difference in promoting phagocytosis of macmphages.S-PPM was stronger in scavenging superoxide anion radical than PPM but it wag vice versa in scavenging hydroxyl radical.Conclusion S-PPM inhibited the cancer cell growth mainly through specific immunity.Sulfate of PPM influenced its quality of scavenging free radicals greatly.

Mechanism of PUFA in regulating of gene expression / 生物医学工程学杂志

Polyunstaurated fatty acids (PUFAs) not only are essential component of cells in maintaining function and composing organelle, but also control gene transcription of enzymes which are involved in differentiation, growth and metabolism in organisms. Resent studies have been shown that PUFA interact directly with nuclear receptors such as PPARs, LXR, HNF-4, other mechanism are indirect and rest with transcription factors such as SREBP. PUFA affect cell function through diverse pathways. The roles of such factors and PUFA in mediating the nuclear effects are addressed in order to elucidate the mechanism of PUFA in regulating gene expression. Further understanding of gene mechanism of regulation at the level of molecule would prompt the development of nutrition, health and medical treatment.

Producing recombinant adenovirus encoding green fluorescent protein (Ad-GFP) by suspension cultured HEK-293 N3S cells / 生物工程学报

Adenovirus vectors are one of the most promising gene transfer systems. They are of great value for gene therapy because these vectors achieve temporal high-level transgene expression and high gene transfer efficiency. To meet increasing needs of adenovirus vectors for gene therapy programs, parallel development of efficient, scalable and reproducible production processes is required. Perfusion cultivation of 293 cells is one of the most commonly used methods to produce adenovirus vectors and it is suitable for industrialized production specially. Experimental studies had been carried out to produce recombinant adenovirus containing the green fluorescent protein gene (Ad-GFP) by perfusion cultivation of HEK-293 N3S cells in a 5L stirring bioreactors. Perfusion rate was 1-2 volume/day. To infect the 293 N3S cells with Ad-GFP at the density of (2-4) x 10(6) cells/ ml. The time of collecting cells was 48 hours post infection. After three rounds of freeze/thaw and centrifugation, the crude viral lysates were stored at--80 degrees C until use. Then to get the Ad-GFP products by 2 x CsCl-gradient purification. The purity of the products was determined by the A260/A280 ratio and a high performance liquid chromatography (HPLC) assay. The infective titer was determined by a TCID50 assay. The culture term was 10-12 days. The infectious titer, the number of virus particle and the ratio of infectious titer to virus particle for the product were 1.0 x 10(11) IU/mL, 1.68 x 10(12) VP/mL and 6.0% IU/VP respectively. The A260/A280 ratio was 1.33, and the purity determined by HPLC was 99.2%. The cell specific productivity was around 1000 IU/cell. By perfusion cultivation of 293 N3S cells in a 5L stirring bioreactors, we established the production process for Ad-GFP, which paves a way to produce other recombinant adenovirus for gene therapy.

Advances in the study on clinical application of natural products from Ascidians / 中国海洋药物

This article summarized the advances in the research of the natural products ET-743,Didemnin B and Aplidine,which were isolated from ascidians, and have been applied to clinical study at present.