FAT10 Silencing Prevents Liver Fibrosis through Regulating SIRT1 Expression in Hepatic Stellate Cells.

Background and objectives: Hepatic stellate cell (HSC) activation is the cardinal factor due to the accumulation of extracellular matrix proteins during the development of liver fibrosis. The aim of the present study was to find new targets for developing drugs to treat liver fibrosis, by screening the key genes involved in the activation of hepatic stellate cells. Methods: Differentially expressed genes were identified through TCGA database. RT-PCR, immunohistochemistry (IHC) assay, western blot, and ELISA were performed to evaluate the expression levels of FAT10 and fibrotic molecules. In vitro experiments were conducted to investigate the signaling pathways and biological functions of FAT10 in LX-2 cell lines. Results: In the present study, expression profiles obtained from the Gene Expression Omnibus (GEO) were used to explore the different genes expression between HSCs treated with or without carbon tetrachloride (CCl4). Human leukocyte antigen (HLA)-F adjacent transcript 10 (FAT10) was selected for further investigations. In animal model of carbon tetrachloride-induced liver fibrosis, the expression of FAT10 on activated HSCs is upregulated. In vitro, silencing FAT10 reduced TGF-ß1-induced ECM activation and accumulation in LX-2 cells, and also suppressed the inflammatory response of LX-2 cells. Further Transwell results suggested that knockdown of FAT10 could inhibit TGF-ß1-induced LX-2 cell migration and invasion. Mechanistically, FAT10 promotes its fibrotic activity through regulating sirtuin 1 (SIRT1), with a concomitant activation of ECM. Conclusions: These findings indicated an unexpected role of FAT10 in liver fibrosis development, suggesting that silencing FAT10 might represent a new strategy for the treatment of fibrotic liver diseases.

Affinity maturation generates pathogenic antibodies with dual reactivity to DNase1L3 and dsDNA in systemic lupus erythematosus.

Anti-dsDNA antibodies are pathogenically heterogeneous, implying distinct origins and antigenic properties. Unexpectedly, during the clinical and molecular characterization of autoantibodies to the endonuclease DNase1L3 in patients with systemic lupus erythematosus (SLE), we identified a subset of neutralizing anti-DNase1L3 antibodies previously catalogued as anti-dsDNA. Based on their variable heavy-chain (VH) gene usage, these antibodies can be divided in two groups. One group is encoded by the inherently autoreactive VH4-34 gene segment, derives from anti-DNase1L3 germline-encoded precursors, and gains cross-reactivity to dsDNA - and some additionally to cardiolipin - following somatic hypermutation. The second group, originally defined as nephritogenic anti-dsDNA antibodies, is encoded by diverse VH gene segments. Although affinity maturation results in dual reactivity to DNase1L3 and dsDNA, their binding efficiencies favor DNase1L3 as the primary antigen. Clinical, transcriptional and monoclonal antibody data support that cross-reactive anti-DNase1L3/dsDNA antibodies are more pathogenic than single reactive anti-dsDNA antibodies. These findings point to DNase1L3 as the primary target of a subset of antibodies classified as anti-dsDNA, shedding light on the origin and pathogenic heterogeneity of antibodies reactive to dsDNA in SLE.

A review on applications of abatacept in systemic rheumatic diseases.

Abatacept is a CTLA-4Ig fusion protein that selectively modulates the CD80/CD86:CD28 costimulatory pathway required for full T-cell activation. The FDA has approved it to be used to treat adult rheumatoid arthritis, juvenile idiopathic arthritis, and adult active psoriatic arthritis. Considering the vital pathogenic role of the CTLA-4 pathway in autoimmune diseases, abatacept could efficiently treat other systemic rheumatic diseases. Here we reviewed the published literature to profile the perspectives about the off-label uses of abatacept, especially in those refractory cases with inadequate responses to conventional therapies and biologic agents. Abatacept can be a promising therapeutic option and contribute to reducing hormone dependence and correlated adverse events.

A Highly Expanded Polycarboxylate Gel and New Environmental Response Effects for Efficiently Adsorbing and Recovering Cu(II) from Water.

A new highly expanded polycarboxylate gel (EPCG) was accidentally formed in a facile cross-linking copolymerization system. When used as an adsorbent material, the EPCG could be quickly expanded 29.44 times in water to have a high permeability inside for realizing the efficient adsorption toward Cu(II) from water. The adsorption capacity of EPCG toward Cu(II) was 261.70 mg/g, which was higher than that of all the selected existing adsorbents reported in recent years. The adsorption rate of expanded EPCG was 3.61 times higher than that of the previous polyantionic gel. Similarly, due to the high expansion and high permeability of EPCG, the EPCG skeleton could be further coated with an alkaline NaOH, forming a novel NaOH-coated EPCG material, and its adsorption capacity toward Cu(II) was further improved to 333.21 mg/g compared to that of pure EPCG adsorbent. Moreover, the EPCG wastes after adsorbing Cu(II) could be fully desorbed to be regenerated for reuse. A total of 99.39% of the adsorbed Cu(II) was desorbed from EPCG wastes to be recovered. The adsorption capacity of regenerated EPCG reused for adsorbing Cu(II) was 259.05 mg/g, which was very near that of the original EPCG. In addition, a series of simulation experiments and instrumental analysis were adopted to confirm the new environmental response effects as the key factors in the purification of Cu(II)-containing wastewater, including "expansion-shrink," "alkali-coating," and "acid-desorption" responses.

Acute Kidney Injury in Hospitalized Patients Infected with COVID-19 from Wuhan, China: A Retrospective Study.

BACKGROUND: Since the first diagnosed case of infection with the novel coronavirus (SARS-CoV-2), there has been a rapid spread of the disease with an increasing number of cases confirmed every day, as well as a rising death toll. An association has been reported between acute kidney injury (AKI) and mortality in patients infected with SARS-CoV-2. Therefore, our study was conducted to explore possible risk factors of AKI as well as whether AKI was a risk factor for worse outcome, especially mortality among patients with coronavirus disease (COVID-19). METHODS: We included all hospital admissions with confirmed or clinically diagnosed COVID-19 from January 29 to February 25, 2020. We collected demographic and epidemiological information, past medical history, symptoms, laboratory tests, treatments, and outcome data from electronic medical records. A total of 492 patients with diagnosed or clinically diagnosed COVID-19 were included in this study. RESULTS: The prevalence rate of AKI was 7.32%. Among the factors associated with AKI, males versus females (aOR 2.73), chronic kidney disease (aOR 42.2), hypertension (aOR 2.82), increased leucocytes (aOR 6.08), and diuretic use (aOR 7.89) were identified as independent risk factors for AKI among patients infected by SARS-CoV-2. There was a significant difference in hospital fees and death in patients with and without AKI (p < 0.05). The mortality rate in patients with AKI was 63.9%. CONCLUSIONS: AKI was widespread among patients with COVID-19. The risk factors of AKI in COVID-19 patients included sex, chronic kidney disease, hypertension, infection, and diuretic use. AKI may be associated with a worse outcome, especially mortality in COVID-19 patients.

Rheumatoid arthritis-associated interstitial lung disease: an overview of epidemiology, pathogenesis and management.

Interstitial lung disease (ILD) accounts for the major cause of morbidity and mortality in rheumatoid arthritis (RA). However, little is known of the pathogenesis, diagnosis and treatment of RA-associated ILD. In this review, we describe our present understanding and ongoing research in RA-ILD. Its aetiology does appear to associate with anti-cyclic citrullinated peptide antibodies, MUC5B mutation and smoking. Another focus of this article is on recent diagnostic methods in RA-ILD. Compared with other methods, high-resolution computed tomography (HRCT) imaging is a main method for the evaluation of ILD in RA patients. Pulmonary function is better suited for assessing progression. An important topic relates to therapeutic intervention. Disease-modifying anti-rheumatic drugs (DMARDs) in RA lack strong evidence in the onset or worsening of ILD. The available literature support that methotrexate, leflunomide, abatacept and rituximab play beneficial roles in the prevention and treatment of RA-ILD.

Clinical features of rheumatic patients infected with COVID-19 in Wuhan, China.

OBJECTIVE: The clinical features of rheumatic patients with coronavirus disease 2019 (COVID-19) have not been reported. This study aimed to describe the clinical features of COVID-19 in rheumatic patients and provide information for handling this situation in clinical practice. METHODS: This is a retrospective case series study. Deidentified data, including gender, age, laboratory and radiological results, symptoms, signs, and medication history, were collected from 2326 patients diagnosed with COVID-19, including 21 cases in combination with rheumatic disease, in Tongji Hospital between 13 January and 15 March 2020. RESULTS: Length of hospital stay and mortality rate were similar between rheumatic and non-rheumatic groups, while the presence of respiratory failure was more common in rheumatic cases (38% vs 10%, p<0.001). Symptoms of fever, fatigue and diarrhoea were seen in 76%, 43% and 23% of patients, respectively. There were four rheumatic patients who experienced a flare of rheumatic disease during hospital stay, with symptoms of muscle aches, back pain, joint pain or rash. While lymphocytopaenia was seen in 57% of rheumatic patients, only one patient (5%) presented with leucopenia in rheumatic cases. Rheumatic patients presented with similar radiological features of ground-glass opacity and consolidation. Patients with pre-existing interstitial lung disease showed massive fibrous stripes and crazy-paving signs at an early stage. Five rheumatic cases used hydroxychloroquine before the diagnosis of COVID-19 and none progressed to critically ill stage. CONCLUSIONS: Respiratory failure was more common in rheumatic patients infected with COVID-19. Differential diagnosis between COVID-19 and a flare of rheumatic disease should be considered. TRIAL REGISTRATION NUMBER: ChiCTR2000030795.

Facilely Synthesized, Highly Permeable, and Efficiently Recyclable Polycationic Gel with Cohesive State Transformations for Purifying Dyeing Wastewater.

A highly permeable polycationic gel (PPG) was designed as a new type of absorbent material, which was prepared by a facile cross-linking copolymerization of 3-chloro-2-hydroxypropylmethyldiallylammonium chloride and dimethyldiallylammonium chloride at 45 °C for 3.0 h. When the PPG absorbent was used for purifying dyeing wastewater, it showed high permeability so that the dyes could fully penetrate into the PPG more easily to be absorbed. Moreover, through Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, optical microscopy, and scanning electron microscopy technologies, the structures of PPG before and after absorption were analyzed, showing that the cohesive states of PPG underwent a great transformation during PPG absorption, and the binding energy of N 1S of PPG increased from 401.66 to 402.15 eV. Because of the new absorption effects of the cohesive state transformations of PPG, the absorption capacity of PPG for absorbing a large-sized dye of Reactive Scarlet 3BS reached 1371.04 mg·g-1, which was 2.07-56.35 times than those of other structural forms of similar cationic absorbents and was 761.69 times higher than that of the frequently used activated carbon. This was the greatest improvement level on the absorption ability of PPG versus the existing absorbents. In addition, PPG achieved excellent recyclability with a mild room-temperature desorption technology, and the absorption capacity of the recycled PPG was 606.76 times higher than that of activated carbon.

Platelet Distribution Width Level in Patients With Systemic Lupus Erythematosus-Associated Pulmonary Arterial Hypertension and Its Diagnostic Value.

OBJECTIVES: This study aims to compare the platelet distribution width (PDW) level in patients with systemic lupus erythematosus-associated pulmonary arterial hypertension (SLE-PAH) with that in patients with systemic lupus erythematosus alone (SLE-non-PAH) and to evaluate the clinical value of the PDW level in the early diagnosis of SLE-PAH. PATIENTS AND METHODS: We analyzed 80 SLE-PAH patients (1 males, 79 females; 34.9±12.3 years; range, 19 to 77 years) and 154 sex- and age-matched SLE-non-PAH patients (4 males, 150 females; mean age 36.7±12.4 years; range, 19 to 69 years) hospitalized between June 2011 and April 2018. All patients underwent transthoracic Doppler echocardiography within three months of inclusion in the study. Age, sex, disease course, currently prescribed medications, clinical manifestations, and past history were collected. Pulmonary artery systolic pressure, ejection fraction, white blood cell count, red blood cell count, hemoglobin, platelet count, PDW, mean platelet volume, erythrocyte sedimentation rate, complement 3 (C3), and C4 levels were also obtained. RESULTS: The PDW level was higher in the SLE-PAH group than that in the SLE-non-PAH group (p=0.023). SLE patients were allocated into high systemic lupus erythematosus disease activity index (SLEDAI) group (SLEDAI score, ≥10) (n=121) or low SLEDAI group (SLEDAI score, <10) (n=113). The PDW level was significantly higher in the high SLEDAI group than that in the low SLEDAI group (p=0.030). The receiver operating characteristic curve was used to evaluate the clinical value of the PDW level in diagnosing PAH in SLE patients. The PDW level was valuable for diagnosing PAH in SLE patients [area under the curve (AUC)=0.591, p=0.023]. The optimal critical value of the PDW level was 14.55 fL. Under these conditions, the sensitivity, specificity, and Youden index were 57%, 63% and 0.20, respectively. For newly diagnosed patients, the PDW level had good diagnostic accuracy, with an AUC of 0.626 (p=0.037). The optimal critical value of the PDW level was 14.65 fL. Under these conditions, the sensitivity, specificity, and Youden index were 66%, 67% and 0.33, respectively. CONCLUSION: The PDW level is a good predictor of SLE-PAH, and this parameter is applicable to various clinical settings.

The presence of P2RX7 single nuclear polymorphism is associated with a gain of function in P2X7 receptor and inflammasome activation in SLE complicated with pericarditis.

OBJECTIVES: A case control study was conducted to evaluate the possible influence of P2RX7 single nuclear polymorphism and P2X7 receptor activity in the susceptibility of SLE with pericarditis in Chinese Han population. METHODS: We studied a cohort of SLE patients with (SLE+PCS) or without (SLE-PCS) history of pericarditis and demographic, therapeutic and clinical data were retrospectively collected. P2RX7 489 C>T (His155Tyr) genotype of each subject was analysed and classified as CC or C>T (CT and TT) variant. After isolation of peripheral blood mononuclear cells and macrophages from whole blood by centrifugation on Ficoll gradient, in vitro macrophage releases of IL-1ß and IL-18 primed by LPS were evaluated by cytometric bead array. NLRP3 expression were evaluated by western blot after normalisation of house-keeping gene α-Tubulin. Finally, P2X7 receptor activity was analysed after stimulation with agonist ATP, by measuring permeability changes using ethidium bromide (EB) uptake fluorescent probe. The Hardy-Weinberg Equilibrium (HWE) analysis was used to detect the association of P2RX7 489C>T SNP with SLE complicated with pericarditis. Spearman linear regression analysis was performed to evaluate the association of macrophages uptake of EB and NLRP3 expression. RESULTS: In total 68 SLE+PCS patients and 72 SLE-PCS patients from the cohort were enrolled. No significant differences in demographic, disease activity and serological features were found between the two subgroups. The HWE analysis detected a significant positive association between SLE+PCS and the 489 C>T SNP (OR=0.65, 95%CI (0.46-0.92), p=0.03). No association was found in SLE-PCS patients carrying either genotype CC or C>T. It was shown that in vitro inflammasome-dependent IL-1ß/IL-18 release from macrophages was higher in SLE+PCS patients compared to SLE-PCS, especially in those bearing the C>T variant genotype, and consequently the WB analysis ofNLRP3 expression in SLE+PCS patients bearing C>T genotype was significantly higher compared to the other genotype carriers (F=13.1, p<0.01). We also detected that macrophages of SLE+PCS patients carrying SNP 489C>T showed a higher EB uptake in response to ATP than subjects carrying wild type (CC). The Spearman linear regression analysis showed a significant association of macrophages EB uptake and NLRP3 expression as well as its dependent IL-1ß and IL-18 in SLE+PCS subjects carrying SNP 489 C>T. CONCLUSIONS: Our results suggest that 489 C>T polymorphism of the P2RX7 gene is associated with activation of inflammasome NLRP3 and an increased release of IL-1ß and IL-18. The EB uptake increase in macrophages of LE+PCS subjects carrying 489C>T displays the functional upregulation of P2RX7, which may be involved in the pathogenesis of SLE complicated with pericarditis in the presence of P2RX7 SNP 489C>T.

Tocilizumab and the risk of respiratory adverse events in patients with rheumatoid arthritis: a systematic review and meta-analysis of randomised controlled trials.

OBJECTIVES: The purpose of this study is to evaluate the relative risk (RR) of respiratory adverse events (AEs) among patients with RA treated with TCZ. METHODS: Databases (PubMed, Embase and Cochrane Library) were searched for randomised controlled trials (RCT) comparing the use of TCZ with placebo (PBO) or active comparator agents in adults with RA published until October 28, 2017. Statistical analyses were conducted to calculate the RR of infectious and non-infectious respiratory AEs and severe AEs (SAEs) using random-effects or fixed-effects models based on the heterogeneity of the included studies. RESULTS: Eight trials were ultimately included. TCZ was associated with an increased risk of infectious respiratory AEs relative to comparator agents (RR 1.53, 95% confidence interval [95% CI] 1.04-2.25) but was not associated with an increased risk of non-infectious respiratory AEs (RR 1.19, 95% CI 0.86-1.64). A subgroup analysis revealed similar results for non-infectious AEs and SAEs in the comparisons of TCZ with MTX and adalimumab (ADA), whereas increased risks of these AEs but not SAEs were observed compared with the PBO. CONCLUSIONS: Our meta-analysis did not reveal an increase in the risk of non-infectious respiratory AEs in adult patients with RA who were treated with TCZ compared with other csDMARDs and bDMARDs in RCTs.

Homologous-heterogeneous structure control and intelligent adsorption effect of a polycationic gel for super-efficient purification of dyeing wastewater.

A homologous-heterogeneous polycationic gel (HPCG) system was constructed by a waste-free synthesis process, to be used as a super-efficient adsorbent material for purifying dyeing wastewater. It is the first discovery of a new intelligent adsorption effect occurring in HPCG adsorption by detecting the homologous-heterogeneous structure transformations in HPCG adsorption using optical microscopy, scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analysis technologies. The adsorption capacities of HPCG products were 532.55-605.45 times higher than that of the widely-used activated carbon, thereby being the greatest improvement of the adsorption ability for HPCG versus this existing adsorbent. Meanwhile, the adsorption capacities of HPCG were also improved by 3.67-46.05 times compared to that of all the similar polycationic cotton adsorbents reported in our previous serial works, demonstrating more efficient purification of dyeing wastewater than we could do before. In addition, through studying the adsorption models, it was further discovered that HPCG adsorption followed the new two-segment adsorption process, i.e. including a speed control segment and an acceleration segment, also confirming the existence of the intelligent adsorption effect for HPCG adsorption.

Increased Autophagy Enhances the Resistance to Tumor Necrosis Factor-Alpha Treatment in Rheumatoid Arthritis Human Fibroblast-Like Synovial Cell.

Tumor Necrosis Factor-alpha (TNF-α) was reported to increase autophagy in rheumatoid arthritis human fibroblast-like synovial cell (RA-HFLS). We investigated different levels of TNF-α exposed to RA-HFLS by focusing on the relationship of autophagy and apoptosis. RA-HFLS and normal human fibroblast-like synovial cell (HFLS) were stimulated by TNF-α in the presence or the absence of 3-methyladenine (3-MA) or chloroquine (CQ). Cell apoptosis was detected by flow cytometry. Autophagy was determined through the expression levels of LC3, Beclin1, and P62 measured by Western Blot analysis as well as Confocal Laser Scanning Microscopy. The basal autophagy level was significantly higher in RA-HFLS than in HFLS. Autophagy was enhanced both in RA-HFLS and HFLS when they were treated with TNF-α. With the treatment of TNF-α, a slightly higher autophagy level was found in RA-HFLS than in HFLS, without a dose dependent effect. When autophagy was inhibited by 3-MA or CQ, apoptosis increased in both groups. With the stimulation of different doses TNF-α, apoptosis was much higher in HFLS group than in RA-HFLS. Autophagy is a protection mechanism when treated by TNF-α in RA-HFLS.

Combination Therapies of Diacerein and Febuxostat Inhibit IL-1ß Responses and Improve Clinical Symptoms in Patients With Refractory Gout.

There are several therapeutic strategies available for the treatment of an acute gout attack and the prevention of recurrent gout flares, and they include nonsteroid anti-inflammatory drugs. This prospective study was aimed at evaluating the efficiency and safety of diacerein in combination with febuxostat on urate control, global assessments of disease activity, self-monitored gouty acute flare times, inflammatory markers, and clinical symptoms associated with their life quantity in patients with refractory gout. A total of 64 patients with refractory gout were sequentially recruited and prescribed with oral febuxostat alone or febuxostat plus diacerein daily for 12 weeks. The intensity of joint pain, numbers of acute flare, disease activity and the levels of serum amyloid A, mature IL-1ß, IL-18, C-reactive protein, and urate in individual subjects were routine analyzed. In comparison with that treatment with febuxostat alone, treatment with both drugs for 12 weeks had a better therapeutic effect on reducing the values of visual analog scales, acute flares, and healthy assessment questionnaire scores in these gout patients. Furthermore, treatment with both drugs also significantly reduced the mean daily dose of etoricoxib and the levels of serum IL-1ß and serum amyloid A. There was no significant difference in the frequency of patients with adverse effect between these 2 groups of patients. In conclusion, combination of diacerein and febuxostat had better therapeutic effect on reducing acute gout flares, inflammation, and clinical symptoms in patients with refractory gout.

Human brucellosis mimicking axial spondyloarthritis: a challenge for rheumatologists when applying the 2009 ASAS criteria.

Although the development of the 2009 SpA classification criteria by Assessment of SpondyloArthritis international Society (ASAS) represents an important step towards a better definition of the early disease stage particularly in axial spondyloarthritis (axSpA), the specificity of the criteria has been criticized these days. As the commonest zoonotic infection worldwide, human brucellosis can mimic a large number of diseases, including SpA. This study was performed to determine the frequency of rheumatologic manifestations in patients with brucellosis and the chance of misdiagnosing them as having axSpA in central China. The results showed that clinical manifestations of axSpA could be observed in brucellosis. Over half of patients had back pain, and one fifth of the patients with back pain were less than 45 years old at onset and had the symptom for more than 3 months. Two young males were falsely classified as suffering from axSpA according to the ASAS criteria, and one with MRI proved sacroiliitis was once given Etanercept for treatment. Therefore, differential diagnosis including human brucellosis should always be kept in mind when applying the ASAS criteria, even in traditionally non-endemic areas.

Retrospective analysis of plasma exchange combined with glucocorticosteroids for the treatment of systemic lupus erythematosus-related acute pancreatitis in central China.

Systemic lupus erythematosus-related acute pancreatitis (SLEAP) has a poor prognosis with a high mortality. We described the clinical features of SLEAP, and discussed the feasibility of plasma exchange (PE) combined with glucocorticosteroids (GC) in short-term prognosis and possible mechanism in reducing serum inflammatory cytokine IL-6 and removing serum lipids. A retrospective study was performed by an independent rheumatologist. Medical records of SLEAP from March 2010 to December 2014 were retrieved from Tongji Hospital information system, and patients were divided into two groups according to whether PE therapy was adopted. Sixteen patients treated with PE in combination with GC were classified as group A, and the other 10 patients who were treated with merely GC were classified as group B. Patients' clinical remission rate and average daily GC dosage after two-week therapy were compared between the two groups. Patients' serum inflammatory cytokines and lipid concentration were compared between baseline and after two-week treatment in both groups. Pearson correlation test was performed to determine association between serum cytokines and Ranson score. SLEDAI score in group A patients at baseline (14.8±3.1) showed no statistical difference from that in group B (14.1±3.3). At baseline serum IL-6 levels had no significant difference between group A [13.14 (11.12, 16.57) mg/L] and group B [14.63 (11.37, 16.37) mg/L]; after two-week therapy IL-6 decreased significantly in group A [9.16 (7.93, 10.75)mg/L] while it did not show decreasing trend in group B [13.62 (9.29,17.63) mg/L]. Serum lipid concentration after two-week therapy in group A [(TC=5.02±0.53, TG=1.46±0.44) mmol/L] decreased significantly compared to baseline [(TC=6.11±0.50, TG=2.14±1.03) mmol/L], while similar tendency was not observed in group B. The remission rate after two-week therapy was higher in group A (70.0%) than in group B (25.0%). Acute pancreatitis (AP) was one of the clinical manifestations of active SLE. PE combined with GC could reduce serum IL-6 level, and remove serum lipid to improve short-term prognosis. Therefore, it might be a safe and effective way in treating SLEAP and was worth continuing to explore its feasibility.

Wnt3a regulates proliferation, apoptosis and function of pancreatic NIT-1 beta cells via activation of IRS2/PI3K signaling.

Wnt-signaling pathway is implicated in pancreatic development and functional regulation of mature beta-cells. Wnt3a/Wnt pathway activation expands islet cell mass in vitro by increasing proliferation and decreasing apoptosis of beta-cells, thereby enhancing its function. However, the signaling pathways that mediate these effects remain unknown. By using a clonal beta-cell line (NIT-1), we examined the role of IRS2/PI3K in the mediation of Wnt3a-stimulated beta-cell growth. Real-time PCR and Western blot were employed to investigate the activity of Wnt/ß-catenin and IRS2/PI3K signaling. Proliferation of NIT-1 cells was assessed by BrdU incorporation, and apoptosis was quantitatively determined by TUNEL and flow cytometry (FCM). Dkk1, an inhibitor of Wnt signaling, and wortmannin, an inhibitor of PI3K, were also used. Results showed that Wnt3a rapidly activated Wnt/ß-catenin signaling, promoted IRS2 expression and Akt phosphorylation in NIT-1 cells. These effects were completely abrogated by Dkk1 or partially eliminated by wortmannin. Wnt3a also promoted NIT-1 cell proliferation, inhibited cytokine-induced beta-cell apoptosis, and increased insulin secretion. Both of these effects were also eliminated by Dkk1 or wortmannin. Our results demonstrated that Wnt3a regulates proliferation, apoptosis and enhances function of pancreatic NIT-1 beta cells via activation of Wnt/ß-catenin signaling, involving crosstalk with IRS2/PI3K signaling, with the effect of Wnt signaling on beta-cells also being IRS2/PI3K/AKT dependent.

Erythropoietin protects pancreatic ß-cell line NIT-1 cells against cytokine-induced apoptosis via phosphatidylinositol 3-kinase/Akt signaling.

OBJECTIVE: Erythropoietin (EPO) is a cytokine that regulates the proliferation, differentiation, and survival of erythroid progenitor cells. EPO has recently been demonstrated to have a tissue-protective role by mediating anti-apoptotic signals through the erythropoietin receptor (EPOR) in various tissues, including brain, liver, and heart. We have previously examined pancreatic ß-cell line NIT-1 cells for the expression of EPOR by real-time PCR and determined that these cells were protected by EPO against cytokine-induced apoptosis. The precise underlying anti-apoptotic mechanisms in pancreatic ß-cells are poorly understood. The purpose of this study is to examine erythropoietin receptor expression in the NIT-1 pancreatic beta-cell line and the intracellular pathway related with its anti-apoptosis effect in NIT-1 cells. METHODS: we examined the expression of EPOR by western blot. We investigate the role of erythropoietin in the survival of these cells, and whether the PI3K/AKT pathway is involved in this protective process. RESULTS: NIT-1 cells expressed EPOR and, in the presence of certain cytokines, exposure of NIT-1 cells to recombinant human erythropoietin (rhEPO) significantly improved the impaired insulin secretion and inhibited cytokine-induced apoptosis. RhEPO caused a rapid activation of Akt and increased expression of Bcl-2. The protective anti-apoptotic effect of rhEPO was significantly abolished by a specific phosphatidylinositol 3-kiniase (PI3K) inhibitor, LY294002. CONCLUSIONS: Our findings indicate that EPOR is expressed in pancreatic ß-cell line NIT-1 cells and suggest that EPO may act as a survival factor requiring the PI3K/Akt pathway.

Increased expression of ganglioside GM1 in peripheral CD4+ T cells correlates soluble form of CD30 in Systemic Lupus Erythematosus patients.

Gangliosides GM1 is a good marker of membrane microdomains (lipid rafts) with important function in cellular activation processes. In this study we found that GM1 expression on CD4+ T cells and memory T cells (CD45RO/CD4) were dramatic increased after stimulation with phytohaemagglutinin in vitro. Next, we examined the GM1 expression on peripheral blood CD4+ T cells and CD8+ T cells from 44 patients with SLE and 28 healthy controls by flow cytometry. GM1 expression was further analyzed with serum soluble CD30 (sCD30), IL-10, TNF-alpha and clinical parameters. The mean fluorescence intensity of GM1 on CD4+ T cells from patients with SLE was significantly higher than those from healthy controls, but not on CD8+ T cells. Increased expression of GM1 was more marked on CD4+/CD45RO+ memory T cells from active SLE patients. Patients with SLE showed significantly elevated serum sCD30 and IL-10, but not TNF-alpha levels. In addition, we found that enhanced GM1 expression on CD4+ T cells from patients with SLE positively correlated with high serum levels of sCD30 and IgG as well as disease activity (SLEDAI scores). Our data suggested the potential role of aberrant lipid raft/GM1 on CD4+ T cells and sCD30 in the pathogenesis of SLE.