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ID PMID Title PublicationDate abstract
25728511 Interleukin-1 receptor associated kinase inhibitors: potential therapeutic agents for infl 2015 Jun The various cells of innate immune system quickly counter-attack invading pathogens, and mount up "first line" defense through their trans-membrane receptors including Toll-like receptors (TLRs) and interleukin receptors (IL-Rs) that result in the secretion of pro-inflammatory cytokines. Albeit such inflammatory responses are beneficial in pathological conditions, their overstimulation may cause severe inflammatory damage; thus, make this defense system a "double edged sword". IRAK-4 has been evaluated as an indispensable element of IL-Rs and TLR pathways that can regulate the abnormal levels of cytokines, and therefore could be employed to manage immune- and inflammation-related disorders. Historically, the identification of selective and potent inhibitors has been challenging; thus, a limited number of small molecule IRAK-4 inhibitors are available in literature. Recently, IRAK-4 achieved great attention, when Ligand® pharmaceutical and Nimbus Discovery® reported the beneficial potentials of IRAK-4 inhibitors in the pre-clinical evaluation for various inflammatory- and immune-related disorders, but not limited to, such as rheumatoid arthritis, inflammatory bowel disease, psoriasis, gout, asthma and cancer.
25716179 The role of IL-17 in CNS diseases. 2015 May Cytokines of the IL-17 family are uniquely placed on the border between immune cells and tissue. Although IL-17 was originally found to induce the activation and mobilization of neutrophils to sites of inflammation, its tissue-specific function is not yet fully understood. The best-studied IL-17 family members, IL-17A and IL-17F, are both typically produced by immune cells such as Th17, γδ T cells and innate lymphoid cells group 3. However, the cells that respond to these cytokines are mostly found in inflamed tissue. As seen in psoriatic skin lesions or in joints of rheumatoid arthritis patients, high levels of IL-17 have been detected in the central nervous system (CNS) during inflammatory responses. Here, we provide a general review of the molecular function of IL-17 and its role in the CNS in particular. Of the different inflammatory conditions of the CNS, we found multiple sclerosis (MS) to be the one most associated with the presence of Th17 cells and IL-17. In particular, many studies using the murine model for MS, experimental autoimmune encephalomyelitis, found a clear association of Th17 and IL-17 with disease severity and progression. We summarize the recent advances made in correlating the presence of IL-17 with impaired blood-brain barrier integrity as well as the activation of astrocytes and microglia and the consequences for disease progression. There is also evidence that IL-17 plays a pathogenic role in the post-ischemic phase of stroke as well as its experimental model. We review the limited but promising data on the sources of post-stroke IL-17 production and its effects on CNS-resident target cells. In addition to MS and stroke, there is also evidence linking high levels of IL-17 to depression, as a frequent comorbidity of several inflammatory diseases, as well as to different types of infections of the CNS. The evidence we supply here suggests that inhibiting the function of the IL-17 cytokine family could have a beneficial effect on pathogenic conditions in the CNS.
25582490 Investigation of the active components in Tripterygium wilfordii leading to its acute hepa 2015 Mar 13 ETHNOPHARMACOLOGICAL RELEVANCE: The traditional herbal medicine Tripterygium wilfordii Hook. f. (TW) has been widely used for the treatment of rheumatoid arthritis and autoimmune disease in the clinic. However, adverse reactions of TW including hepatotoxicity and nephrotoxicity have been frequently reported. Terpenes and alkaloids are among the most important active components in TW. Triptolide (TP), a major terpene in TW, has been found to induce toxicity, and metabolic pathways could lead to detoxification of TP. In this study, whether other major terpenes or alkaloids in TW contribute to its toxicity was investigated. The role of metabolic eliminations in their potential detoxification process was also evaluated. MATERIALS AND METHODS: The toxicity of TW and its five major active components (one terpene and four alkaloids) in mice was evaluated in terms of mortality and blood biochemical levels (ALT, AST, BUN and CREA). TP was used as a positive control. Metabolic pathways leading to potential detoxification of TW or its two representative components (triptonide and wilforgine) were evaluated in glutathione (GSH)-depleted (treated with L-buthionine-S,R-sulfoxinine, BSO) and aminobenzotriazole (ABT; a nonspecific inhibitor for P450s)-treated mice. RESULTS: In normal mice, the major metabolic pathways for the terpene compounds TP and triptonide (TN) were hydroxylation and cysteine conjugation, and the alkaloid wilforgine (WG) mainly underwent oxidative metabolism and hydrolysis. In ABT/BSO-treated mice, the hydroxylated metabolites of TP, TN and WG were found at a lower level than normal mice, and the level of cysteine conjugates of TN increased probably due to the stress response. Compared with normal mice, mortality and levels of ALT (but not BUN) were significantly higher (P<0.01) in TW (or TP)-treated mice (1.2 mg kg(-1)), indicating the acute toxicity (may not nephrotoxicity) of TW and its active component TP. Pretreatment with ABT and/or BSO increased the acute toxicity (including hepatotoxicity and nephrotoxicity) caused by TW or TP. No significant toxicity was found for TN or four alkaloids in normal mice or ABT/BSO-treated mice. CONCLUSIONS: TP was probably the main contributor to the toxicity of TW, and the terpene TN and alkaloids in TW may be of no toxicological concern at dosage levels up to 20-fold of the therapeutic dose. Metabolic eliminations to less reactive metabolites implied a high potential for detoxification of TW, and caution should be taken for TW clinical use during co-administration with other CYP inhibitors or GSH-depleting agents.
25529454 Identification of heat shock protein 27 as a novel autoantigen of Behçet's disease. 2015 Jan 24 OBJECTIVE: The aim of this study was to identify candidate pathogenic autoantigens of Behçet's disease (BD) in pathogen-stimulated target cells. METHODS: First, three cell lines were used as target cells to screen autoantibody. Second, selected target cells were simulated with pathogens. Third, western blotting was used for detecting the auto-antigens in cell extracts. Next, immunoprecipitation was performed and the amino-acid sequences of target antigens were analyzed by LC-MALDI-TOF/TOF. Then, the potential target antigen was expressed, purified, and immunologically confirmed. And finally, an ELISA kit was developed and clinically validated through the assessments of 456 clinical samples with BD. RESULTS: One antigen with a molecular weight of approximately 27-kDa was identified as heat shock protein 27 (HSP27). The reactivity of serum IgG against recombinant human HSP27 was detected in 52 of 91 BD patients (57%), 66 of 92 rheumatoid arthritis (RA) patients (72%), 32 of 90 Sjogren syndrome (SS) patients (36%), 22 of 92 systemic lupus erythematosus (SLE) patients (24%) and 0 of 91 healthy controls (HC). The reactivity of BD serum IgG antibodies against HSP27 was significantly higher than SLE (P<0.0001) SS (P<0.0001) and HC (P<0.0001). CONCLUSIONS: This study identified HSP27 as a candidate endothelial cell autoantigen of BD, which is interesting and probably worth further exploration.
25266062 Association of quality of life with laboratory measurements and lifestyle factors in commu 2015 OBJECTIVES: Little is known about the influence of routine laboratory measurements and lifestyle factors on generic quality of life (QOL) at older ages. We aimed to study the relationship between generic QOL and laboratory measurements and lifestyle factors in community dwelling older Chinese people. METHODS: We conducted a cross-sectional analysis. Six hundred and ninety nine elders were randomly selected from the examinees of the annual health examination in Taipei City, Taiwan. Blood, urine and stool of the participants were examined and lifestyle data were collected. Participants completed the CASP-19 (control, autonomy, self-realization, pleasure) questionnaire, a 19-item QOL scale. The relationship between QOL and laboratory results and lifestyle factors was explored, using multiple linear regression and profile analysis. RESULTS: The mean age of the participants was 75.5 years (SD = 6.5), and 49.5% were female. Male gender standardized β coefficients (β = 0.122) and exercise habit (β = 0.170) were associated with a better QOL, whereas advanced age (β = -0.242), blurred vision (β = -0.143), depression (β = -0.125), central obesity (β = -0.093), anemia (β = -0.095), rheumatoid arthritis (β = -0.073), Parkinsonism (β = -0.079), malignancy (β = -0.086) and motorcycle riding (β = -0.086) were associated with a lower QOL. Profile analysis revealed that young-old males, social drinkers, regular exercisers and car drivers had the best QOL (all p < 0.001). CONCLUSION: Of the many laboratory measurements, only anemia was associated with the lower QOL. By contrast, several lifestyle factors, such as social drinking, exercise habit and car driving, were associated with better QOL, whereas abdominal obesity and motorcycle riding were associated with lower QOL.
25053584 Risk factors for the periprosthetic fracture after total hip arthroplasty: a systematic re 2015 Sep BACKGROUND AND AIMS: A systematic review and meta-analysis was performed to investigate the risk factors associated with periprosthetic fracture after total hip arthroplasty. MATERIAL AND METHODS: We searched potential studies in the following databases: MEDLINE, Embase, Web of Science, SCOPUS and Cochrane CENTRAL up to December 2013. Newcastle-Ottawa Scale was used to evaluate the methodological quality, and Stata 11.0 was used to perform all the analyses. RESULTS: Seven studies altogether, including 1069 cases of periprosthetic fractures and 74,776 controls, were included in the meta-analysis. Compared to those absent following demographic or medical conditions, patients involved with female gender (odds ratio, 1.534; p < 0.001), advanced age (>80) (odds ratio: 4.203; p < 0.001), revision (odds ratio: 4.398; p < 0.001), rheumatoid arthritis (odds ratio: 2.503; p < 0.001), osteonecrosis (odds ratio: 1.563; p = 0.009), and implant type of Exeter (odds ratio: 1.511; p = 0.017) were more likely to sustain periprosthetic fractures. Osteoarthritis (vs not) (odds ratio: 0.449; p < 0.001) was identified a protective factor for periprosthetic fractures after total hip arthroplasty. The other factors, including lower ages, American Society of Anesthesiologists ≥ 3, and other implant types, were not significant risk factors for periprosthetic fractures. CONCLUSIONS: These medical conditions as reminder should be kept in clinicians' mind and close follow-up should be implemented in patients involved for preventing the occurrence of periprosthetic fractures after total hip arthroplasty.
24171693 An insight on human skin penetration of diflunisal: lipogel versus hydrogel microemulsion. 2015 Jan Diflunisal is a NSAID used in acute and long term management of pain and inflammation associated with osteoarthritis, rheumatoid arthritis and symptoms of primary dysmenorrhea. However, its oral use is associated with side effects such as peptic ulceration, dyspepsia, gastrointestinal disturbances and bleeding. The aim of this work was to develop lecithin organogels (LO) transdermal delivery system for diflunisal and to study its human skin penetration ability in comparison with an optimized microemulsion-based hydrogel. Ternary phase diagrams were constructed using butyl lactate as an organic solvent and two commercial grades of lecithin. The formation of gel phase was lecithin concentration dependent with Phosholipion 85 G being capable of forming organogels at lower lecithin concentration than Lipoid S75. The gels prepared using butyl lactate were able to tolerate higher amounts of water than could be incorporated in the lipogels prepared with other organic solvents. All the investigated gels possessed acceptable physical properties and were able to deliver diflunisal through human skin. The lipogels delivered higher total drug amount through the skin than the hydrogel. The composition of lecithin seemed to have some effect on the skin permeability enhancement ability of the lipogel. Lecithin containing higher amount of phosphatidyl ethanolamine could provide better transdermal delivery. The elaborated lecithin organogels are potential carriers that create a good opportunity for transdermal delivery of diflunisal overcoming the side effects associating its oral route.
27558590 Opposing regulation of the late phase TNF response by mTORC1-IL-10 signaling and hypoxia i 2016 Aug 25 Tumor necrosis factor (TNF) is best known for inducing a rapid but transient NF-κB-mediated inflammatory response. We investigated later phases of TNF signaling, after the initial transient induction of inflammatory genes has subsided, in primary human macrophages. TNF signaling induced expression of late response genes, including inhibitors of NF-κB and TLR signaling, with delayed and sustained kinetics 6-24 hr after TNF stimulation. A subset of late phase genes was expressed in rheumatoid arthritis synovial macrophages, confirming their expression under chronic inflammatory conditions in vivo. Expression of a subset of late phase genes was mediated by autocrine IL-10, which activated STAT3 with delayed kinetics. Hypoxia, which occurs at sites of infection or inflammation where TNF is expressed, suppressed this IL-10-STAT3 autocrine loop and expression of late phase genes. TNF-induced expression of IL-10 and downstream genes was also dependent on signaling by mTORC1, which senses the metabolic state of cells and is modulated by hypoxia. These results reveal an mTORC1-dependent IL-10-mediated late phase response to TNF by primary human macrophages, and identify suppression of IL-10 responses as a new mechanism by which hypoxia can promote inflammation. Thus, hypoxic and metabolic pathways may modulate TNF responses during chronic inflammation.
27912193 Comparative tissue distribution and excretion study of alkaloids from Herba Ephedrae-Radix 2017 Feb 5 Herba Ephedrae-Radix Aconiti Lateralis, composed of Ephedrae (Mahuang in Chinese) and Radix Aconiti Lateralis (Fuzi in Chinese), is a classical herbal combination proven to be effective in treating common cold, asthma, and rheumatoid arthritis. Alkaloids, bioactive components of the herbal extract, have been associated with many side effects. Nine alkaloids, including norephedrine, norpseudoephedrine, ephedrine, pseudoephedrine, methylephedrine, hypaconitine, benzoylaconine, benzoylmesaconine and benzoylhypaconine, were simultaneously quantified within 14.5min, by a validated ultra-performance liquid chromatography-tandem mass spectrometry method in various rat tissues, urine, and feces after oral administration of Mahuang-Fuzi and single-herb extracts. The results indicated that the alkaloids were widely distributed in the heart, liver, spleen, lung, kidney, and brain. Lower bioavailability and higher clearance of some alkaloids were observed for the herbal combination, but hypaconitine showed a longer residence time and lower clearance. Elimination kinetics demonstrated that ephedra and aconitum alkaloids were mainly excreted in urine and feces, respectively. The tissue distribution and excretion of ephedra and aconitum alkaloids are comprehensively reported for the first time for the Mahuang-Fuzi combination. Compared with single-herb extracts, lower extraction efficiencies of alkaloids in vitro were observed which may result in their lower intake. However, the combination showed a prolonged residence time and delayed elimination of aconitum alkaloids, which increases the risk of drug accumulation. The study demonstrated potential risks of intoxication with aconitum alkaloids, associated with the use of Fuzi in combination with Mahuang. Mahuang-Fuzi is a classical combination used in clinics, further investigation is needed.
27864660 Effects of CYP2C9 genetic polymorphisms on the pharmacokinetics of celecoxib and its carbo 2017 Mar Celecoxib, a selective cyclooxygenase (COX)-2 inhibitor, is used for the treatment of rheumatoid arthritis and osteoarthritis. The predominant hepatic metabolism of celecoxib to celecoxib carboxylic acid (CCA) is mediated mainly by CYP2C9. We investigated the effects of the major CYP2C9 genetic variants in Asian populations, CYP2C9*3 and CYP2C9*13, on the pharmacokinetics of celecoxib and its carboxylic acid metabolite in healthy Korean subjects. A single 200-mg oral dose of celecoxib was given to 52 Korean subjects with different CYP2C9 genotypes: CYP2C9EM (n = 26; CYP2C9*1/*1), CYP2C9IM (n = 24; CYP2C9*1/*3 and *1/*13), and CYP2C9PM (n = 2; CYP2C9*3/*3). Celecoxib and CCA concentrations in plasma samples collected up to 48 or 96 h after drug intake were determined by HPLC-MS/MS. The mean area under the plasma concentration-time curve (AUC(0-∞)) of celecoxib was increased 1.63-fold (P < 0.001), and the apparent oral clearance (CL/F) of celecoxib was decreased by 39.6% in the CYP2C9IM genotype group compared with that of CYP2C9EM (P < 0.001). The overall pharmacokinetic parameters for celecoxib in CYP2C9*1/*13 subjects were similar to those in CYP2C9*1/*3 subjects. Two subjects with CYP2C9PM genotype both showed markedly higher AUC(0-∞), prolonged half-life, and lower CL/F for celecoxib than did subjects with CYP2C9EM and IM genotypes. CYP2C9*3 and CYP2C9*13 variant alleles significantly affected the plasma concentration of celecoxib.
27826099 Post-translational modified proteins are biomarkers of autoimmune-processes: NETosis and t 2017 Jan Basic research is showing new mechanisms involved in early immune responses and Neutrophil Extracellular Trap (NET) formation (or NETosis) is of key importance as first line defense against bacteria, virus and protozoa. Enzymatic modification of arginine in citrulline in histones is the prerequisite of NETosis being it necessary for decondensation and extrusion of DNA from cells; it is conceivable that other post translational modifications may occur during this event. There is consensus in considering that post translational modified proteins may elicit an autoimmune response that leads to the formation of autoantibodies. Several autoimmune diseases seem to share these pathogenic mechanisms, in particular Rheumatoid arthritis, Systemic Lupus Erythematosus, Small Vessel Vasculitis and Anti-Phospholipid Syndrome, which are all characterized by high levels of circulating autoantibodies. Autoimmunity has, however, different targets and elicits different clinical responses. It seems reasonable to hypothesize that although NETosis is common to all the conditions above, NET components are different and potentially responsible for different autoimmune responses. On the other hand also showing whether circulating NET remnants are present as free structures in blood/biological fluids and determine their levels is relevant to autoimmunity. This review is intended to discuss the rationale for utilizing new discoveries that could be of rapid clinical application and lead to the development of early biomarkers of autoimmunity to predict and treat otherwise serious conditions.
27760064 The Association Between Body Mass Index (BMI) and Back or Leg Pain in Patients With Spinal 2016 Oct 15 STUDY DESIGN: A prospective observational study. OBJECTIVE: The aim of this study was to identify the relationship between obesity, quantified by body mass index (BMI), and both back and leg pain in spinal patients. SUMMARY OF BACKGROUND DATA: Obesity and back pain are massive public health problems. Given the poor correlation between pain and a pathological change in the spine, further investigation is required into other, nonpathological predictors such as obesity. METHODS: The Genodisc Study was one of the largest cross-sectional studies of patients presenting to tertiary spinal units and recruited from six centers in four European countries. In total, 2636 patients were recruited over a 5-year period between 2008 and 2013. Both back and leg pain were scored by patients in the range of 0 to 10. Linear regression was used to model the relationship between BMI and pain. Potential confounders included in the model were age, Zung Depression score, episodes of sport, gender, disability benefit, family history, previous surgery, smoking status, work type, clinical diagnosis, and relevant comorbidities. Back and leg pain outcomes were modeled separately. RESULTS: The study included 1160 men and 1349 women with a mean age of 50.9 years and mean BMI of 27.2 kg/m. In our fully adjusted model, a 5-point increase in BMI was associated with greater leg [0.19 units (95% confidence interval 0.08-0.31)] but not back [0.10 units (95% CI -0.02 to 0.22)] pain scores. Although this relationship was statically significant, given the small magnitude of the relationship, the clinical significance is limited. Similarly, female gender, heavy workload, rheumatoid arthritis, previous spine surgery, and depression were associated with higher back and leg pain. CONCLUSION: In this large observational study of spine patients presenting to tertiary European centers, obesity, as measured by increased BMI, was associated with greater leg pain. LEVEL OF EVIDENCE: 2.
27608420 IL-15 and RANKL Play a Synergistically Important Role in Osteoclastogenesis. 2017 Apr Interleukin-15 (IL-15), a cytokine secreted by several cell types, has important physiological roles in the activity, proliferation, and viability of immune cells. It has both chemoattractant and proinflammatory properties, and may promote bone destruction. A previous study has shown that IL-15 alone exerts no effect on osteoclastogenesis. Therefore, the current study addressed the synergistic effect of IL-15 on osteoclast formation using RAW264.7 (RAW) cells by co-stimulation with receptor activator of nuclear factor (NF)-κB ligand (RANKL) that has a major role in osteoclastogenesis involving the pathogenesis of rheumatoid arthritis and periodontal disease. Co-stimulation of RAW cells by IL-15 and RANKL significantly increased the gene expression of osteoclast differentiation and osteoclastogenesis markers compared with stimulation by RANKL or IL-15 independently as evaluated by tartrate-resistant acid phosphate-positive cell numbers, the fusion index, a pit formation assay with Alizarin red staining (calcification estimation), and quantitative polymerase chain reaction. Phosphorylation of extracellular signal-regulated kinase (ERK), c-jun N-terminal kinase, p38 mitogen-activated protein kinase, and NF-κB was significantly increased by RANKL and IL-15 (P < 0.05) compared with RANKL alone. In addition, these differentiation activities induced by RANKL and IL-15 were comparatively suppressed by inhibition of ERK, suggesting that this synergistic effect on osteoclastogenesis is mainly mediated by ERK. Taken together, our results demonstrate that IL-15 and RANKL induce osteoclastogenesis synergistically, and IL-15 might play a novel and major role in destructive inflammatory bone diseases. J. Cell. Biochem. 118: 739-747, 2017. © 2016 Wiley Periodicals, Inc.
27397553 Risk factors for periprosthetic joint infection following primary total hip or knee arthro 2017 Jun To identify risk factors for periprosthetic joint infection following primary total joint arthroplasty, a systematic search was performed in Pubmed, Embase and Cochrane library databases. Pooled odds ratios (ORs) or standardised mean differences (SMDs) with 95% confidence intervals (CIs) were calculated. Patient characteristics, surgical-related factors and comorbidities, as potential risk factors, were investigated. The main factors associated with infection after total joint arthroplasty (TJA) were male gender (OR, 1·48; 95% CI, 1.19-1.85), age (SMD, -0·10; 95% CI, -0.17--0.03), obesity (OR, 1·54; 95% CI, 1·25-1·90), alcohol abuse (OR, 1·88; 95% CI, 1·32-2·68), American Society of Anesthesiologists (ASA) scale > 2 (OR, 2·06; 95% CI, 1·77-2·39), operative time (SMD, 0·49; 95% CI, 0·19-0·78), drain usage (OR, 0·36; 95% CI, 0·18-0·74), diabetes mellitus (OR, 1·58; 95% CI, 1·37-1·81), urinary tract infection (OR, 1·53; 95% CI, 1.09-2.16) and rheumatoid arthritis (OR, 1·57; 95% CI, 1·30-1·88). Among these risk factors, ASA score > 2 was a high risk factor, and drain usage was a protective factor. There was positive evidence for some factors that could be used to prevent the onset of infection after TJA.
27379100 Combined Expression of IFN-γ, IL-17, and IL-4 mRNA by Recall PBMCs Moderately Discriminat 2016 New biomarkers are needed for discriminating active tuberculosis (TB) from latent TB infection (LTBI), especially in vulnerable groups representing the major diagnostic challenge. This pilot study was carried out to explore the diagnostic potential of selected genes, IFN-γ, IL-17, IL-4, and FoxP3, associated with TB immunity and immunopathology. IFN-γ, IL-17, IL-4, and FoxP3 mRNA expression levels were measured by quantitative reverse transcription PCR (RT-qPCR) from antigen-stimulated peripheral blood mononuclear cells of patients with active TB (n = 25); patients with miscellaneous inflammatory disorders and concomitant LTBI (n = 20), rheumatoid arthritis (RA) being the most predominant in the group (n = 11); and in healthy Bacillus Calmette-Guérin (BCG) vaccinees (n = 8). While the levels of FoxP3 mRNA did not differ between the tested groups, the cumulative expression levels of purified protein derivative-stimulated IFN-γ, IL-17, and IL-4 mRNAs were found to distinguish active TB from the whole group of LTBI with 48% sensitivity and 85% specificity. When restricting the LTBI group to RA cases only, the sensitivity was 56% and specificity 100%. When interpreting the result as positive in at least one of the mRNAs IFN-γ, IL-17, or IL-4, sensitivity of 64% and specificities of 75% (heterogeneous group of LTBI) or 100% (LTBI with RA) were achieved. Moderate discrimination of active TB from LTBI with miscellaneous inflammatory underlying conditions by using combined quantitative expression of IFN-γ, IL-17, and IL-4 mRNA seems not to be of high diagnostic potential.
27058977 High-throughput screening and radioligand binding studies reveal monoamine oxidase-B as th 2016 May 1 AIMS: d-deprenyl is a useful positron emission tomography tracer for visualization of inflammatory processes. Studies with [(11)C]-d-deprenyl showed robust uptake in peripheral painful sites of patients with rheumatoid arthritis or chronic whiplash injury. The mechanism of preferential d-deprenyl uptake is not yet known, but the existence of a specific binding site was proposed. Thus, in the present study, we sought to identify the binding site for d-deprenyl and verify the hypothesis about the possibility of monoamine oxidase enzymes as major targets for this molecule. MAIN METHODS: A high-throughput analysis of d-deprenyl activity towards 165G-protein coupled receptors and 84 enzyme targets was performed. Additionally, binding studies were used to verify the competition of [(3)H]d-deprenyl with ligands specific for targets identified in the high-throughput screen. KEY FINDINGS: Our high-throughput investigation identified monoamine oxidase-B, monoamine oxidase-A and angiotensin converting enzyme as potential targets for d-deprenyl. Further competitive [(3)H]d-deprenyl binding studies with specific inhibitors identified monoamine oxidase-B as the major binding site. No evident high-affinity hits were identified among G-protein coupled receptors. SIGNIFICANCE: Our study was the first to utilize a high-throughput screening approach to identify putative d-deprenyl targets. It verified 249 candidate proteins and confirmed the role of monoamine oxidase - B in d-deprenyl binding. Our results add knowledge about the possible mechanism of d-deprenyl binding, which might aid in explaining the increased uptake of this compound in peripheral inflammation. Monoamine oxidase-B will be further investigated in future studies utilizing human inflamed synovium.
26994919 Wide tolerance to amino acids substitutions in the OCTN1 ergothioneine transporter. 2016 Jun BACKGROUND: Organic cation transporters transfer solutes with a positive charge across the plasma membrane. The novel organic cation transporter 1 (OCTN1) and 2 (OCTN2) transport ergothioneine and carnitine, respectively. Mutations in the SLC22A5 gene encoding OCTN2 cause primary carnitine deficiency, a recessive disorders resulting in low carnitine levels and defective fatty acid oxidation. Variations in the SLC22A4 gene encoding OCTN1 are associated with rheumatoid arthritis and Crohn disease. METHODS: Here we evaluate the functional properties of the OCTN1 transporter using chimeric transporters constructed by fusing different portion of the OCTN1 and OCTN2 cDNAs. Their relative abundance and subcellular distribution was evaluated through western blot analysis and confocal microscopy. RESULTS: Substitutions of the C-terminal portion of OCTN1 with the correspondent residues of OCTN2 generated chimeric OCTN transporters more active than wild-type OCTN1 in transporting ergothioneine. Additional single amino acid substitutions introduced in chimeric OCTN transporters further increased ergothioneine transport activity. Kinetic analysis indicated that increased transport activity was due to an increased V(max), with modest changes in K(m) toward ergothioneine. CONCLUSIONS: Our results indicate that the OCTN1 transporter is tolerant to extensive amino acid substitutions. This is in sharp contrast to the OCTN2 carnitine transporter that has been selected for high functional activity through evolution, with almost all substitutions reducing carnitine transport activity. GENERAL SIGNIFICANCE: The widespread tolerance of OCTN1 to amino acid substitutions suggests that the corresponding SLC22A4 gene may have derived from a recent duplication of the SLC22A5 gene and might not yet have a defined physiological role.
26936374 GRK2 overexpression inhibits IGF1-induced proliferation and migration of human hepatocellu 2016 May G protein-coupled receptor kinase 2 (GRK2) is a serine/threonine kinase that is involved in a variety of important signaling pathways and alternation of GRK2 protein level or activity causes diseases such as heart failure, rheumatoid arthritis, and obesity. However, the role and mechanism of GRK2 in hepatocellular carcinoma (HCC) progression is not fully investigated. In this study we found that GRK2 plays an inhibitory role in IGF1-induced HCC cell proliferation and migration. Overexpression of GRK2 causes a decrease in early growth response-1 (EGR1) expression, while knockdown of GRK2 leads to marked increase in EGR1 expression in the treatment of IGF1. Through co-immunoprecipitation and western blot assay, we confirmed that GRK2 can interact with insulin-like growth factor 1 receptor (IGF-1R) and inhibits IGF1-induced activation of IGF1R signaling pathway. Silencing EGR1 attenuates GRK2 overexpression-caused inhibition of cell proliferation, tumor colony number and migration activity, while overexpressing of EGR1 restores the anti-proliferative and migratory effect by GRK2 overexpression in HCCLM3 cells. Collectively, these results suggest that GRK2 may inhibit IGF1-induced HCC cell growth and migration through downregulation of EGR1 and indicate that enforced GRK2 may offer a potential therapeutic approach against HCC.
26840958 Inhibition of Cellular Adhesion by Immunological Targeting of Osteopontin Neoepitopes Gene 2016 Osteopontin (OPN), a secreted protein involved in inflammatory processes and cancer, induces cell adhesion, migration, and activation of inflammatory pathways in various cell types. Cells bind OPN via integrins at a canonical RGD region in the full length form as well as to a contiguous cryptic site that some have shown is unmasked upon thrombin or matrix metalloproteinase cleavage. Thus, the adhesive capacity of osteopontin is enhanced by proteolytic cleavage that may occur in inflammatory conditions such as obesity, atherosclerosis, rheumatoid arthritis, tumor growth and metastasis. Our aim was to inhibit cellular adhesion to recombinant truncated proteins that correspond to the N-terminal cleavage products of thrombin- or matrix metalloproteinase-cleaved OPN in vitro. We specifically targeted the cryptic integrin binding site with monoclonal antibodies and antisera induced by peptide immunization of mice. HEK 293 cells adhered markedly stronger to truncated OPN proteins than to full length OPN. Without affecting cell binding to the full length form, the raised monoclonal antibodies specifically impeded cellular adhesion to the OPN fragments. Moreover, we show that the peptides used for immunization were able to induce antisera, which impeded adhesion either to all OPN forms, including the full-length form, or selectively to the corresponding truncated recombinant proteins. In conclusion, we developed immunological tools to selectively target functional properties of protease-cleaved OPN forms, which could find applications in treatment and prevention of various inflammatory diseases and cancers.
26748399 Epigallocatechin-3-gallate protects against tumor necrosis factor alpha induced inhibition 2016 Mar Anabolic bone accruement through osteogenic differentiation is important for the maintenance of physiological bone mass and often disrupted in various inflammatory diseases. Epigallocatechin-3-gallate, as an antioxidant and anti-inflammatory agent, has been suggested for potential therapeutic use in this context, possibly by the inhibition of bone resorption as well as the enhancement of bone formation through directly activating osteoblast differentiation. However, the reported effects of epigallocatechin-3-gallate modulating osteoblast differentiation are mixed, and the underlying molecular mechanism is still elusive. Moreover, there is limited information regarding the effects of epigallocatechin-3-gallate on osteogenic potential of mesenchymal stem cell in inflammation. Here, we examined the in vitro osteogenic differentiation of human mesenchymal stem cells. We found that the cell viability and osteoblast differentiation of human bone marrow-derived mesenchymal stem cells are significantly inhibited by inflammatory cytokine TNFα treatment. Epigallocatechin-3-gallate is able to enhance the cell viability and osteoblast differentiation of mesenchymal stem cells and is capable of reversing the TNFα-induced inhibition. Notably, only low doses of epigallocatechin-3-gallate have such benefits, which potentially act through the inhibition of NF-κB signaling that is stimulated by TNFα. These data altogether clarify the controversy on epigallocatechin-3-gallate promoting osteoblast differentiation and further provide molecular basis for the putative clinical use of epigallocatechin-3-gallate in stem cell-based bone regeneration for inflammatory bone loss diseases, such as rheumatoid arthritis and prosthetic osteolysis.