Effect of secondary lymphoid tissue chemokine suppression on experimental ulcerative colitis in mice

The secondary lymphoid tissue chemokine (CCL21) is closely associated with lymphoid homing and anti-tumor immune responses. CCL21 also has a chemotactic effect on intestinal lymphocytes. This study mainly focused on CCL21 expression in experimental ulcerative colitis and on the effects of CCL21 suppression on this disease in mice. The mouse colitis model was induced by dextran sulfate sodium (DSS) in 40 female BALB/c mice that were equally distributed into five groups: control, DSS, propylene glycol, triptolide (TL), and dexamethasone treatment groups. The disease activity index, general morphology score of the colon, and histological pathology score of colon tissues were evaluated. CCL21 expression was examined in colons of mice by immunohistochemistry, reverse transcription-polymerase chain reaction, and Western blotting analysis. CCL21 was upregulated in the mouse model of ulcerative colitis (control group vs DSS group/propylene glycol group, P<0.01). The TL and dexamethasone treatments improved colitis symptoms and decreased CCL21 expression (TL group/dexamethasone group vs DSS group/propylene glycol group, P<0.05). In conclusion, CCL21 was shown to be involved in the induction of ulcerative colitis. Suppression of CCL21 expression decreased damage induced from ulcerative colitis, indicating that CCL21 targeted therapy might be an effective treatment for this disease.

Thermal and athermal crackling noise in ferroelastic nanostructures

The evolution of ferroelastic microstructures under external shear is determined by large-scale molecular dynamics simulations in two and three dimensions. Ferroelastic pattern formation was found to be almost identical in two and three dimensions, with only the ferroelastic transition temperature changing. The twin patterns generated by shear deformation depend strongly on temperature, with high wall densities nucleating under optimized temperature conditions. The dynamical tweed and mobile kink movement inside the twin walls is continuous and thermally activated at high temperatures, and becomes jerky and athermal at low temperatures. With decreasing temperature, the statistical distributions of dynamical tweed and kinks vary from a Vogel-Fulcher law P(E)~exp-(E/(T-TVF)) to an athermal power-law distribution P(E)~E-E. During the yield event, the nucleation of needles and kinks is always jerky, and the energy of the jerks is power-law distributed. Low-temperature yield proceeds via one large avalanche. With increasing temperature, the large avalanche is thermally broken up into a multitude of small segments. The power-law exponents reflect the changes in temperature, even in the athermal regime.

Transforming growth factor-β1-induced Treg cells inhibit the absorption of tissue-engineered cartilage caused by endogenous IFN-γ and TNF-α

BACKGROUND

In a previous study, we showed that IFN-γ and TNF-α induce bone marrow mesenchymal stem cell (BMMSC) apoptosis and absorption of tissue-engineered cartilage, but the induced regulatory T cells (iTreg) inhibit the function of IFN-γ and TNF-α. In this study, we investigated the effect of iTreg cells on the absorption of tissue-engineered cartilage caused by endogenous IFN-γ and TNF-α.

METHODS

We transfected the TGF-β1 gene into BMMSCs co-cultured with CD4(+) T lymphocytes. Then, we assessed the expression of iTreg cell markers (Foxp3, CD25 and CD 39) and IFN-γ and TNF-α and the level of apoptosis of BMMSCs. In addition, we characterized chondrogenic-committed cells from TGF-β1(+)BMMSCs and explored the role of iTreg cells.

RESULTS

IFN-γ and TNF-α were detected in the groups with CD4(+) T cells. In the group in which TGF-β1(+)BMMSCs were co-cultured with CD4(+) T cells, we observed Foxp3(+)Treg/ CD25(+)CD39(+) (17.58 ± 0.45%) cells as well as significant inhibition of BMMSC apoptosis and tissue-engineered cartilage absorption.

CONCLUSIONS

CD4(+) T cells led to the absorption of tissue-engineered cartilage through the secretion of endogenous IFN-γ and TNF-α, whose inflammatory functions were concomitantly suppressed by iTreg cells converted from CD4(+) T cells. This study is clinically relevant and adds to our understanding of the mechanism of tissue-engineered cartilage absorption.

Anp32e, a higher eukaryotic histone chaperone directs preferential recognition for H2A.Z

H2A.Z is a highly conserved histone variant in all species. The chromatin deposition of H2A.Z is specifically catalyzed by the yeast chromatin remodeling complex SWR1 and its mammalian counterpart SRCAP. However, the mechanism by which H2A.Z is preferentially recognized by non-histone proteins remains elusive. Here we identified Anp32e, a novel higher eukaryote-specific histone chaperone for H2A.Z. Anp32e preferentially associates with H2A.Z-H2B dimers rather than H2A-H2B dimers in vitro and in vivo and dissociates non-nucleosomal aggregates formed by DNA and H2A-H2B. We determined the crystal structure of the Anp32e chaperone domain (186-232) in complex with the H2A.Z-H2B dimer. In this structure, the region containing Anp32e residues 214-224, which is absent in other Anp32 family proteins, specifically interacts with the extended H2A.Z αC helix, which exhibits an unexpected conformational change. Genome-wide profiling of Anp32e revealed a remarkable co-occupancy between Anp32e and H2A.Z. Cells overexpressing Anp32e displayed a strong global H2A.Z loss at the +1 nucleosomes, whereas cells depleted of Anp32e displayed a moderate global H2A.Z increase at the +1 nucleosomes. This suggests that Anp32e may help to resolve the non-nucleosomal H2A.Z aggregates and also facilitate the removal of H2A.Z at the +1 nucleosomes, and the latter may help RNA polymerase II to pass the first nucleosomal barrier.

A pilot study of the SARC-F scale on screening sarcopenia and physical disability in the Chinese older people

INTRODUCTION

The SARC-F scale is a newly developed tool to diagnose sarcopenia and obviate the need for measurement of muscle mass. SARC-F ≥ 4 is defined as sarcopenia. The questions of SARC-F cover physical functions targeting sarcopenia or initial presentation for sarcopenia. The aim of the study is to explore the application of SARC-F in the Chinese people.

METHODS

Two hundred thirty Chinese people over 65 years old were assessed by the SARC-F scale, PSMS, Lawton IADL and the shortened version of the falls efficacy scale-international(the short FES-I). Hospitalization was investigated. Physical performance and strength were measured. The association of SARC-F with other scales or tests was analyzed.

RESULTS

Poor physical performance and grip strength were associated with SARC-F ≥ 4 independently (P<0.005). The κ value for agreement of SARC-F ≥ 4 and cutoff points of tests were 0.391 to 0.635. The short FES-I were correlated to SARC-F scores (Spearman's coefficient 0.692). Poor PSMS and Lawton IADL scores were associated with SARC-F ≥ 4(P=0.000) and SARC-F ≥ 4 was associated with hospitalization in the past 2 years (P=0.000).

CONCLUSION

The SARC-F scale can identify old Chinese people with impaired physical function who may suffered from sarcopenia. SARC-F judgment reflects fear of falling, indicates the hospitalization events and is associated with ability of daily life. Thus, SARC-F may be a simple and useful tool for screening individuals with impaired physical function. Further studies on SARC-F in Chinese people would be worthy.

Expression of HMGA2 in bladder cancer and its association with epithelial-to-mesenchymal transition

OBJECTIVES

High mobility group protein2 (HMGA2) and epithelial-to-mesenchymal transition are both related to progress of bladder cancer, however, the relationship between HMGA2, E-cadherin and vimentin in bladder cancer is not yet known. Thus, this study has examined expression of HMGA2, E-cadherin and vimentin in bladder cancer and investigated their relationship.

MATERIALS AND METHODS

The 5637 bladder cancer cell line and SV-HUC-1 normal uroepithelial cells were used to study expression of HMGA2, E-cadherin and vimentin using RT-PCR and western blotting. Paraffin wax-embedded bladder cancer tissues were used to study protein expression using immunohistochemistry and χ(2) analysis and Kendall's correlation were utilized statistical methods.

RESULTS

Overexpression of HMGA2 was associated with down-regulation of E-cadherin and up-regulation of vimentin in the 5637 bladder cancer line. A total of 49 paraffin wax-embedded tissues of transitional cell bladder cancer were used. Positive expression levels of HMGA2 protein and vimentin were 41 and 43% in bladder tissues, respectively. No expression of E-cadherin was found in 43%. Expression of HMGA2, loss of E-cadherin and expression of vimentin are all significantly correlated with bladder cancer grade and stage. Loss of E-cadherin and expression of vimentin both correlated with recurrence of the bladder cancer.

CONCLUSIONS

Expression of HMGA2 was closely associated with occurrence of epithelial-to-mesenchymal transition. Expression of HMGA2, loss of E-cadherin and expression of vimentin may indicate high degree malignancy of bladder cancer. Loss of E-cadherin expression and positive expression of vimentin may predict recurrence of bladder cancer.

Immunostimulant Activity of a Novel Polysaccharide Isolated from Lactarius deliciosus (L. ex Fr.) Gray

More and more fungal polysaccharides have been reported to exhibit a variety of biological activities, including antitumor, antioxidant and immunostimulant activity. The non-starch polysaccharides have emerged as an important class of bioactive natural products. In this study, the immune activities of a novel polysaccharide (LDG-A) isolated from Lactarius deliciosus (L. ex Fr.) Gray were investigated at 20, 40 and 80 mg/kg dose levels. The inhibitory rate in mice treated with 80 mg/kg LDG-A can reach 68.422%, being the highest in the three doses, which may be comparable to mannatide. Histology of immune organs showed that the tissues were arranged in more regular and firm pattern, but the tumor tissue arranged looser in LDG-A group than those in control group. Meanwhile, there was no obvious damage to other organs, such as heart, lung, and kidney. The antitumor activity of the LDG-A was usually believed to be a consequence of the stimulation of the cell-mediated immune response because it can significantly promote the lymphocyte and macrophage cells in the dose range of 50-200 μg/ml and 100-400 μg/ml in vitro, respectively. The level of cytokines (IL-6, TNF-α, and NO) of macrophage cells induced by LDG-A treatment was similar to lipopolysaccharides at different concentrations. The expression of all these genes studied (TNF-α, IL-6, and iNOS mRNA) in the untreated macrophage was little, but increased dramatically in a dose-dependent manner in the LDG-A-treated cells. The results obtained in the present study indicated that the purified polysaccharide of L. deliciosus (L. ex Fr.) Gray is a potential source of natural immune-stimulating substances.

Associations of clinical features and prognosis with age at disease onset in patients with systemic lupus erythematosus

The objective of this study is to evaluate the association of clinical features and prognosis with age at disease onset in patients with systemic lupus erythematosus (SLE) in a large, multicenter Chinese cohort. Medical records of 1898 SLE inpatients from 15 hospitals were reviewed and classified into three groups according to their ages at disease presentation. Categorical data were analyzed by chi-square test and potentially associated factors were tested by multinomial logistic regression. Among the patients studied, 259 (13.6%) were juvenile onset (≤18 years), 1444 (76.1%) were early onset (>18 and ≤45 years) and 195 (10.3%) were late onset (>45 years). Whenever manifestations occurred, most patients (>80%) were diagnosed within two years. Juvenile-onset patients were more likely to be untreated before admission ( p < 0.001) and have mucocutaneous manifestations ( p < 0.001), but musculoskeletal symptoms ( p < 0.05) and leukopenia ( p < 0.05) were less frequent, while comorbidities were much higher in patients with late-onset SLE ( p < 0.001). Neuropsychiatric, cardiopulmonary, renal and gastrointestinal involvement, disease activity index and damage scores were similar among three groups. Anti-Sm antibodies were less prevalent in late-onset patients ( p < 0.05) and antimalarial drugs were more often applied to juvenile-onset patients ( p < 0.001). As expected, mortality was elevated in the late-onset SLE group ( p < 0.05), in which nearly half died of infections, which was much higher than those in the other two groups ( p < 0.001). Logistic regression confirmed that patients with juvenile- and early-onset disease were associated with high incidence of being untreated prior to admission, and with low incidence of comorbidities as well as deaths caused by infection compared to patients with late-onset lupus. Interestingly, our data showed that more patients with late-onset disease had a SLEDAI score change of >7 at discharge. In conclusion, age at onset has an impact on SLE disease status, and infection is the main cause of death in those with late-onset lupus. Considering that the late-onset patients had simultaneously easily controllable diseases and high incidence of comorbidities, a different treatment strategy from younger patients should be considered.

Overexpression, purification, and pharmacologic evaluation of anticancer activity of ribosomal protein L24 from the giant panda (Ailuropoda melanoleuca)

The ribosomal protein L24 (RPL24) belongs to the L24E family of ribosomal proteins and is located in the cytoplasm. The purpose of this study was to investigate the structure and anti-cancer function of RPL24 of the giant panda (Ailuropoda melanoleuca). The complementary DNA of RPL24 was cloned successfully using reverse transcription-polymerase chain reaction technology. We constructed a recombinant expression vector containing RPL24 complementary DNA and overexpressed it in Escherichia coli using pET28a plasmids. The expression product obtained was purified using Ni-chelating affinity chromatography. The results indicated that the length of the fragment cloned is 509 bp, and it contains an open-reading frame of 474 bp encoding 157 amino acids. Primary structure analysis revealed that the molecular weight of the putative RPL24 protein is 17.78 kDa with a theoretical isoelectric point of 11.86. The RPL24 gene is readily expressed in E. coli, and the RPL24 fused with the N-terminal histidine-tagged protein to give rise to the accumulation of an expected 23.51-kDa polypeptide. The inhibitory rate in mice treated with 0.1 mg/mL RPL24, the highest of 3 doses administered, can reach 67.662%, which may be comparable to the response to mannatide. The histology of organs with tumors showed that the tissues in the RPL24 group displayed a looser arrangement compared with that in the control group. Furthermore, no obvious damage was apparent in other organs, such as heart, lung, and kidney. The data showed that the recombinant RPL24 had time and dose dependency on the cell growth inhibition rate. Human laryngeal carcinoma Hep-2 cells treated with 0.3125-10 µg/mL RPL24 for 24 h displayed significant cell growth inhibition (P < 0.05; N = 6) in assays using 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide compared with that in control (untreated) cells. By contrast, human hepatoma Hep G-2 cells displayed no significant change (P > 0.05; N = 6) from control (untreated) cells. RPL24 has time and dose dependency on Hep-2 cell growth inhibition. The data indicate that the effect at low concentrations is better than that at high concentrations, and the concentration of 0.625 µg/mL provides the best rate of growth inhibition. Further research is ongoing to determine the bioactive principles of recombinant RPL24 protein that are responsible for its anticancer activity.

Histone H2A ubiquitination inhibits the enzymatic activity of H3 lysine 36 methyltransferases

Histone H3 lysine 27 (H3K27) methylation and H2A monoubiquitination (ubH2A) are two closely related histone modifications that regulate Polycomb silencing. Previous studies reported that H3K27 trimethylation (H3K27me3) rarely coexists with H3K36 di- or tri-methylation (H3K36me2/3) on the same histone H3 tails, which is partially controlled by the direct inhibition of the enzymatic activity of H3K27-specific methyltransferase PRC2. By contrast, H3K27 methylation does not affect the catalytic activity of H3K36-specific methyltransferases, suggesting other Polycomb mechanism(s) may negatively regulate the H3K36-specific methyltransferase(s). In this study, we established a simple protocol to purify milligram quantities of ubH2A from mammalian cells, which were used to reconstitute nucleosome substrates with fully ubiquitinated H2A. A number of histone methyltransferases were then tested on these nucleosome substrates. Notably, all of the H3K36-specific methyltransferases, including ASH1L, HYPB, NSD1, and NSD2 were inhibited by ubH2A, whereas the other histone methyltransferases, including PRC2, G9a, and Pr-Set7 were not affected by ubH2A. Together with previous reports, these findings collectively explain the mutual repulsion of H3K36me2/3 and Polycomb modifications.

Glucagon-like peptide-1 upregulates visfatin expression in 3T3-L1 adipocytes

The incretin hormone glucagon-like peptide-1 (GLP-1) exerts important functions in controlling glucose homeostasis. Many studies have revealed molecular targets of GLP-1, but its influence on adipokines has not been determined. Visfatin, a recently discovered adipokine, has been shown to attenuate insulin resistance by binding to insulin receptor. Our study shows that GLP-1 induced secretion of visfatin into the culture medium of 3T3-L1 adipocytes due to increased visfatin mRNA expression. Furthermore, the effect of GLP-1 on visfatin was dose- and time-dependent. H89, a protein kinase A inhibitor, prevented the induction of visfatin expression by GLP-1. Moreover, inhibition of NF-κB by PDTC reduced the basal visfatin release while having no effect on the transcription regulation by GLP-1. In addition, GLP-1 alleviated the decrease of visfatin mRNA expression under endoplasmic reticulum stress induced by thapsigargin. Taken together, our study suggests that GLP-1 promotes the novel insulin-mimetic adipocytokine visfatin expression via the PKA pathway and might influence glucose metabolism.

Effect of adjunctive roxithromycin therapy on interleukin-1β, transforming growth factor-β1 and vascular endothelial growth factor in gingival crevicular fluid of cyclosporine A-treated patients with gingival overgrowth

BACKGROUND AND OBJECTIVE

Systemic macrolide antibiotic administration has been shown to result in the elimination or reduction cyclosporine A-induced gingival overgrowth. Roxithromycin (ROX) is known to have anti-inflammatory, immunomodulatory and tissue reparative effects. This study was to evaluate the effect of adjunctive ROX therapy on cyclosporine A-induced gingival overgrowth and interleukin (IL)-1β, transforming growth factor (TGF)-β1 and vascular endothelial growth factor (VEGF) levels in gingival crevicular fluid of renal transplant patients.

MATERIAL AND METHODS

Thirty-one patients with clinically significant overgrowth and 16 periodontally healthy subjects were included in this randomized, double-blind, placebo-controlled, parallel-arm study. Patients received scaling and root planing (SRP) at baseline and randomized to take either ROX or placebo for 5 d. The clinical parameters, including plaque index, papillary bleeding index, probing depth and gingival overgrowth scores, were recorded. The amounts of IL-1β, TGF-β1 and VEGF in gingival crevicular fluid were detected by ELISA. Periodontal parameters as well as gingival crevicular fluid biomarker levels were evaluated at baseline and at 1 and 4 wk post-therapy.

RESULTS

Following SRP plus ROX and SRP plus placebo therapy, significant improvements in clinical periodontal parameters of both study groups were observed (p < 0.025). In the ROX group, adjunctive ROX therapy resulted in a greater gingival overgrowth scores reduction compared with those in the placebo group at 4 wk (p < 0.017). Initial amounts of IL-1β, TGF-β1 and VEGF for both the ROX and placebo groups were significantly higher than those for healthy subjects (p < 0.017), with no statistical difference between the two study groups. At 1 and 4 wk post-therapy, significant decreases in the amounts of IL-1β, TGF-β1 and VEGF were observed in both study groups when compared with baseline (p < 0.025), but there was no difference in the levels of IL-1β and VEGF between the two study groups. The amount of decrease in TGF-β1 levels for the ROX group was statistically significant compared to that for the placebo group at 4 wk after treatment (p < 0.017).

CONCLUSION

Our study indicated that combination of ROX with non-surgical therapy improves gingival overgrowth status and decreases gingival crevicular fluid TGF-β1 levels in patients with severe gingival overgrowth. The reduction of gingival crevicular fluid TGF-β1 following ROX therapy suggests an anti-inflammatory/immunomodulatory effect of ROX on the treatment of cyclosporine A-induced gingival overgrowth.

Loss of cell adhesion molecule CHL1 improves homeostatic adaptation and survival in hypoxic stress

Close homologue of L1 (CHL1) is a transmembrane cell adhesion molecule that is critical for brain development and for the maintenance of neural circuits in adults. Recent studies revealed that CHL1 has diverse roles and is involved in the regulation of recovery after spinal cord injury. CHL1 expression was downregulated in the cerebral cortex, hypothalamus, and brain stem after the induction of acute hypoxia (AH). In the current study, we sought to address the role of CHL1 in regulating homeostasis responses to hypoxia using CHL1-knockout (CHL1^−/−) mice. We found that, compared with wild-type littermates, CHL1^−/− mice showed a dramatically lower mortality rate and an augmented ventilatory response after they were subjected to AH. Immunofluorescence staining revealed that CHL1 was expressed in the carotid body (CB), the key oxygen sensor in rodents, and CHL1 expression level in the CB as assayed by western blot was decreased after hypoxic exposure. The number of glomus cells and the expression of tyrosine hydroxylase (a marker for glomus cells) in the CB of CHL1^−/− mice appeared to be increased compared with CHL1^+/+ mice. In addition, in the ex vivo CB preparation, hypoxia induced a significantly greater afferent nerve discharge in CHL1^−/− mice compared with CHL1^+/+ mice. Furthermore, the arterial blood pressure and plasma catecholamine levels of CHL1^−/− mice were also significantly higher than those of CHL1^+/+ mice. Our findings first demonstrate that CHL1 is a novel intrinsic factor that is involved in CB function and in the ventilatory response to AH.