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Editorial Rheumatoid cachexia: a complication of rheumatoid arthritis moves into the 21st century. free! 2009
Roubenoff R. · No affiliation provided · Arthritis Res Ther. · Pubmed #19439037 links to free full text
Abstract: Rheumatoid cachexia, loss of muscle mass and strength and concomitant increase in fat mass, is very common in patients with rheumatoid arthritis (RA). Despite great advances in the treatment of RA, it appears that rheumatoid cachexia persists even after joint inflammation improves. Rheumatoid cachexia may be an important risk factor for cardiovascular disease and excess mortality in RA. In this issue of Arthritis Research & Therapy, Elkan and colleagues demonstrate a link between rheumatoid cachexia and metabolic syndrome, further reinforcing the need for therapy directed beyond inflammation and at the metabolic consequences of RA.
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Review Rheumatoid cachexia: metabolic abnormalities, mechanisms and interventions. free! 2004
Rall LC, Roubenoff R. · Epidemiology Research Center, ML-2, Marshfield Clinic Research Foundation, 1000 N. Oak Avenue, Marshfield, WI 54449, USA. · Rheumatology (Oxford). · Pubmed #15292530 links to free full text
Abstract: We have previously identified the phrase 'rheumatoid cachexia' to describe the loss of body cell mass (BCM) that may occur among patients with rheumatoid arthritis (RA). Specifically, rheumatoid cachexia is characterized by altered energy and protein metabolism (reduced total energy expenditure, increased resting energy expenditure and increased whole-body protein catabolism) and increased inflammatory cytokine production (interleukin-1beta and tumour necrosis factor-alpha). Patients with rheumatoid cachexia consistently have a diet that appears adequate in protein and calories (based on US Dietary Reference Intakes), but with reduced physical activity. These phenomena are similar to some of the metabolic abnormalities that occur with normal ageing, but the aetiology appears to be different in RA. This review will focus on describing the metabolic abnormalities observed in rheumatoid cachexia, identifying potential mechanisms for loss of BCM and discussing strategies for intervention.
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Review Sarcopenic obesity: does muscle loss cause fat gain? Lessons from rheumatoid arthritis and osteoarthritis. 2000
Roubenoff R. · Nutrition, Exercise Physiology, and Sarcopenia (NEPS) Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts 02111, USA. · Ann N Y Acad Sci. · Pubmed #10865804 No free full text.
This publication has no abstract.
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Clinical Conference Peripheral blood expression of nuclear factor-kappab-regulated genes is associated with rheumatoid arthritis disease activity and responds differentially to anti-tumor necrosis factor-alpha versus methotrexate. 2007
Parker A, Izmailova ES, Narang J, Badola S, Le T, Roubenoff R, Ginsburg GS, Maier A, Coblyn JS, Shadick NA, Weinblatt ME. · Millennium Pharmaceuticals Inc., Cambridge, Massachusetts, USA. · J Rheumatol. · Pubmed #17696278 No free full text.
Abstract: OBJECTIVE: To evaluate peripheral blood expression of genes regulated by nuclear factor-kappaB (NF-kappaB), a key mediator of tumor necrosis factor-alpha (TNF-alpha) signaling, in patients with rheumatoid arthritis (RA) before and during treatment with anti-TNF-alpha or methotrexate (MTX). We analyzed association of gene expression with disease activity, rheumatoid factor (RF), age, sex, disease duration, treatment modality, and clinical response. METHODS: Sixty patients consented for RNA analysis at baseline and after 2 and 6 weeks of treatment. Disease activity was quantified using Disease Activity Score (DAS28) and C-reactive protein (CRP). Expression of 67 TNF-alpha-responsive, NF-kappaB-regulated genes was measured using Affymetrix arrays and RT-PCR. RESULTS: Expression of 34 genes was associated with DAS28-CRP, notably S100A12/calgranulin C, IL7R, and aquaporin 3. No association was observed with age, sex, RF, or disease duration. Expression of 16 genes changed in a manner that differed significantly between treatment groups. Eleven were reduced in anti-TNF-alpha-treated patients relative to MTX, while 5 were increased. The majority of these observations were confirmed using RT-PCR. Gene expression was not associated significantly with change in disease activity. CONCLUSION: NF-kappaB-dependent gene expression in peripheral leukocytes is highly correlated with RA activity as measured by DAS28-CRP. Expression of many genes responds differentially to anti-TNF-alpha versus MTX, suggesting fundamentally different effects on the NF-kappaB pathway. This peripheral blood expression signature provides candidate markers that could lead to development of a simple, minimally invasive pharmacodynamic assay for RA treatments directed at the NF-kappaB pathway. Combination of gene expression data with clinical scores and serum markers may provide more sensitive and predictive measures of RA disease activity.
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Clinical Conference Effect of Tai Chi in adults with rheumatoid arthritis. free! 2005
Wang C, Roubenoff R, Lau J, Kalish R, Schmid CH, Tighiouart H, Rones R, Hibberd PL. · No affiliation provided · Rheumatology (Oxford). · Pubmed #15741197 links to free full text
This publication has no abstract.
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Clinical Conference Effect of vitamin E supplementation on vitamin K status in adults with normal coagulation status. free! 2004
Booth SL, Golly I, Sacheck JM, Roubenoff R, Dallal GE, Hamada K, Blumberg JB. · Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA. · Am J Clin Nutr. · Pubmed #15213041 links to free full text
Abstract: BACKGROUND: Cases of enhanced anticoagulant effect in response to high-dose vitamin E supplementation have been reported among patients taking oral anticoagulants. Although a vitamin E-vitamin K interaction was proposed to underlie this effect, it has not been systematically investigated in adults with normal baseline coagulation status. OBJECTIVE: The objective was to study the effect of 12 wk of supplementation with 1000 IU RRR-alpha-tocopherol/d on biochemical measures of vitamin K status in men and women not taking oral anticoagulants. DESIGN: Vitamin K status, which was assessed with the use of plasma phylloquinone concentrations, the degree of under-gamma-carboxylation of prothrombin (proteins induced by vitamin K absence-factor II, PIVKA-II), and the percentage of undercarboxylated osteocalcin (ucOC), was determined in 38 men and women with rheumatoid arthritis (study A) and in 32 healthy men (study B) participating in 2 independent, 12-wk randomized clinical trials of vitamin E supplementation (1000 IU/d). RESULTS: Mean (+/- SD) PIVKA-II increased from 1.7 +/- 1.7 to 11.9 +/- 16.1 ng/mL (P < 0.001) in study A and from 1.8 +/- 0.6 to 5.3 +/- 3.9 ng/mL (P < 0.001) in study B in response to 12 wk of vitamin E supplementation. An increase in PIVKA-II is indicative of poor vitamin K status. In contrast, the other measures of vitamin K status (ie, plasma phylloquinone concentration and percentage of ucOC) did not change significantly in response to the supplementation. CONCLUSIONS: High-dose vitamin E supplementation increased PIVKA-II in adults not receiving oral anticoagulant therapy. The clinical significance of these changes warrants further investigation, but high doses of vitamin E may antagonize vitamin K. Whether such an interaction is potentially beneficial or harmful remains to be determined.
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Article Genome-wide association study of determinants of anti-cyclic citrullinated peptide antibody titer in adults with rheumatoid arthritis. free! 2009
Cui J, Taylor KE, Destefano AL, Criswell LA, Izmailova ES, Parker A, Roubenoff R, Plenge RM, Weinblatt ME, Shadick NA, Karlson EW. · Division of Rheumatology, Immunology & Allergy, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA. · Mol Med. · Pubmed #19287509 links to free full text
Abstract: We carried out a genome-wide association study of genetic predictors of anti-cyclic citrullinated peptide antibody (anti-CCP) level in 531 self-reported non-Hispanic Caucasian Rheumatoid Arthritis (RA) patients enrolled in the Brigham Rheumatoid Arthritis Sequential Study (BRASS). For replication, we then analyzed 289 single nucleotide polymorphisms (SNPs) with P < 0.001 in BRASS in an independent population of 849 RA patients from the North American Rheumatoid Arthritis Consortium (NARAC). BRASS and NARAC samples were genotyped using the Affymetrix 100K and Illumina 550K platforms respectively. Association between SNPs and anti-CCP titer was tested using general linear models. The five most significant SNPs from BRASS all were within the major histocompatibility complex (MHC) region (P < or = 3.5 x 10(-6)). After controlling for the human leukocyte antigen shared epitope (HLA-SE), the top SNPs still yielded P values < 0.0002. In NARAC, a single SNP from the MHC region near BTNL2 and HLA-DRA, rs1980493 (r(2) = 0.85 with the top five SNPs from BRASS), was associated significantly with CCP titer (P = 6.1 x 10(-5)) even after adjustment for the HLA-SE (P = 0.0002). The top SNPs found in BRASS and NARAC had r(2) = 0.46 and 0.64, respectively, to HLA-DRB1 DR3 alleles. These results confirm that the most significant genome region affecting anti-CCP titers in RA is the MHC region. We identified a SNP in moderate linkage disequilibrium (LD) with HLA-DR3, which may influence anti-CCP titer independently of the HLA-SE.
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Article Genome-wide association scan identifies candidate polymorphisms associated with differential response to anti-TNF treatment in rheumatoid arthritis. free! 2008
Liu C, Batliwalla F, Li W, Lee A, Roubenoff R, Beckman E, Khalili H, Damle A, Kern M, Furie R, Dupuis J, Plenge RM, Coenen MJ, Behrens TW, Carulli JP, Gregersen PK. · Biogen Idec Inc., Cambridge, Massachusetts, USA. · Mol Med. · Pubmed #18615156 links to free full text
Abstract: The prediction of response (or non-response) to anti-TNF treatment for rheumatoid arthritis (RA) is a pressing clinical problem. We conducted a genome-wide association study using the Illumina HapMap300 SNP chip on 89 RA patients prospectively followed after beginning anti-TNF therapy as part of Autoimmune Biomarkers Collaborative Network (ABCoN [Autoimmune Bio-markers Collaborative Network]) patient cohort. Response to therapy was determined by the change in Disease Activity Score (DAS28) observed after 14 wks. We used a two-part analysis that treated the change in DAS28 as a continuous trait and then incorporated it into a dichotomous trait of "good responder" and "nonresponder" by European League Against Rheumatism (EULAR) criteria. We corrected for multiple tests by permutation, and adjusted for potential population stratification using EIGENSTRAT. Multiple single nucleotide polymorphism (SNP) markers showed significant associations near or within loci including: the v-maf musculoaponeurotic fibrosarcoma oncogene homolog B (MAFB) gene on chromosome 20; the type I interferon gene IFNk on chromosome 9; and in a locus on chromosome 7 that includes the paraoxonase I (PON1) gene. An SNP in the IL10 promoter (rs1800896) that was previously reported as associated with anti-TNF response was weakly associated with response in this cohort. Replications of these results in independent and larger data sets clearly are required. We provide a reference list of candidate SNPs (P < 0.01) that can be investigated in future pharmacogenomic studies.
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Article Two independent alleles at 6q23 associated with risk of rheumatoid arthritis. free! 2007
Plenge RM, Cotsapas C, Davies L, Price AL, de Bakker PI, Maller J, Pe'er I, Burtt NP, Blumenstiel B, DeFelice M, Parkin M, Barry R, Winslow W, Healy C, Graham RR, Neale BM, Izmailova E, Roubenoff R, Parker AN, Glass R, Karlson EW, Maher N, Hafler DA, Lee DM, Seldin MF, Remmers EF, Lee AT, Padyukov L, Alfredsson L, Coblyn J, Weinblatt ME, Gabriel SB, Purcell S, Klareskog L, Gregersen PK, Shadick NA, Daly MJ, Altshuler D. · Program in Medical and Population Genetics, Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA. · Nat Genet. · Pubmed #17982456 links to free full text
Abstract: To identify susceptibility alleles associated with rheumatoid arthritis, we genotyped 397 individuals with rheumatoid arthritis for 116,204 SNPs and carried out an association analysis in comparison to publicly available genotype data for 1,211 related individuals from the Framingham Heart Study. After evaluating and adjusting for technical and population biases, we identified a SNP at 6q23 (rs10499194, approximately 150 kb from TNFAIP3 and OLIG3) that was reproducibly associated with rheumatoid arthritis both in the genome-wide association (GWA) scan and in 5,541 additional case-control samples (P = 10(-3), GWA scan; P < 10(-6), replication; P = 10(-9), combined). In a concurrent study, the Wellcome Trust Case Control Consortium (WTCCC) has reported strong association of rheumatoid arthritis susceptibility to a different SNP located 3.8 kb from rs10499194 (rs6920220; P = 5 x 10(-6) in WTCCC). We show that these two SNP associations are statistically independent, are each reproducible in the comparison of our data and WTCCC data, and define risk and protective haplotypes for rheumatoid arthritis at 6q23.
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Article Preliminary evidence shows that folic acid fortification of the food supply is associated with higher methotrexate dosing in patients with rheumatoid arthritis. 2007
Arabelovic S, Sam G, Dallal GE, Jacques PF, Selhub J, Rosenberg IH, Roubenoff R. · US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, Massachusetts 02111, USA. · J Am Coll Nutr. · Pubmed #17914133 No free full text.
Abstract: BACKGROUND: Fortification of the diet with folate has been used in the United States since 1997 to prevent neural tube defects in newborn babies. However, an increase in dietary folate intake could theoretically reduce the effectiveness of the anti-folate medication, methotrexate (MTX) in treating rheumatoid arthritis (RA) and other inflammatory diseases. OBJECTIVE: To investigate whether dietary fortification with folic acid interferes with MTX function in patients with RA. METHODS: We computed MTX dose per patient per year for the years 1988 to 1999 and plotted these against time, comparing the overall mean MTX dose before and after 1997, when dietary fortification with folic acid was instituted in the USA. Thirty-six subjects met eligibility criteria. RESULTS: Mean annual MTX dose was stable between 1988 and 1996 (12.4 +/- 4.0mg), but then rose linearly from 1997 to 1999 (16.6 +/- 5.1 mg, p < 0.001). CONCLUSIONS: This preliminary study suggests that folic acid supplementation may contribute to higher MTX dosing in patients with RA.
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Article Associations between human leukocyte antigen, PTPN22, CTLA4 genotypes and rheumatoid arthritis phenotypes of autoantibody status, age at diagnosis and erosions in a large cohort study. free! 2008
Karlson EW, Chibnik LB, Cui J, Plenge RM, Glass RJ, Maher NE, Parker A, Roubenoff R, Izmailova E, Coblyn JS, Weinblatt ME, Shadick NA. · Division of Rheumatology, Allergy, and Immunology, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA. · Ann Rheum Dis. · Pubmed #17666451 links to free full text
Abstract: BACKGROUND: HLA-DRB1 shared epitope (HLA-SE), PTPN22 and CTLA4 alleles are associated with cyclic citrullinated peptide (CCP) and rheumatoid arthritis (RA). OBJECTIVE: We examined associations between HLA-SE, PTPN22, CTLA4 genotypes and RA phenotypes in a large cohort to (a) replicate prior associations with CCP status, and (b) determine associations with radiographic erosions and age of diagnosis. METHODS: A total of 689 RA patients from the Brigham RA Sequential Study (BRASS) were genotyped for HLA-SE, PTPN22 (rs2476601) and CTLA4 (rs3087243). Association between genotypes and CCP, rheumatoid factor (RF) erosive phenotypes and age at diagnosis were assessed with multivariable models adjusting for age, sex and disease duration. Novel causal pathway analysis was used to test the hypothesis that genetic risk factors and CCP are in the causal pathway for predicting erosions. RESULTS: In multivariable analysis, presence of any HLA-SE was strongly associated with CCP+ (odds ratio (OR) 3.05, 95% CI 2.18-4.25), and RF+ (OR 2.53, 95% CI 1.83-3.5) phenotypes; presence of any PTPN22 T allele was associated with CCP+ (OR 1.81, 95% CI 1.24-2.66) and RF+ phenotypes (OR 1.84, 95% CI 1.27-2.66). CTLA4 was not associated with CCP or RF phenotypes. While HLA-SE was associated with erosive RA phenotype (OR 1.52, 95% CI 1.01-2.17), this was no longer significant after conditioning on CCP. PTPN22 and CTLA4 were not associated with erosive phenotype. Presence of any HLA-SE was associated with an average 3.6 years earlier diagnosis compared with absence of HLA-SE (41.3 vs 44.9 years, p = 0.002) and PTPN22 was associated with a 4.2 years earlier age of diagnosis (39.5 vs 43.6 years, p = 0.002). CTLA4 genotypes were not associated with age at diagnosis of RA. CONCLUSIONS: In this large clinical cohort, we replicated the association between HLA-SE and PTPN22, but not CTLA4 with CCP+ and RF+ phenotypes. We also found evidence for associations between HLA-SE, and PTPN22 and earlier age at diagnosis. Since HLA-SE is associated with erosive phenotype in unconditional analysis, but is not significant after conditioning on CCP, this suggests that CCP is in the causal pathway for predicting erosive phenotype.
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Article Opposing effects of the D70 mutation and the shared epitope in HLA-DR4 on disease activity and certain disease phenotypes in rheumatoid arthritis. 2007
Shadick NA, Heller JE, Weinblatt ME, Maher NE, Cui J, Ginsburg G, Coblyn J, Anderson R, Solomon DH, Roubenoff R, Parker A. · Division of Rheumatology, Immunology, Allergy, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA. · Ann Rheum Dis. · Pubmed #17491100 No free full text.
Abstract: BACKGROUND: Certain sequences present in the hypervariable region of human leucocyte antigen (HLA)-DRB1 known as the shared epitope (SE) are hypothesised to increase the risk of rheumatoid arthritis (RA), whereas alleles encoding aspartic acid at position 70 (D70 alleles) may have a protective effect. METHODS: Patient HLA-DRB1 serotypes were assessed and the genotypes encoding the SE motif or the putatively protective D70 motif identified in a large RA cohort. Logistic regression was used to analyse associations of genotype with presence of disease, comorbidities and disease severity, and association between genotype and change in disease activity over time. RESULTS: The 689 patients enrolled had a mean (SD) age of 57.9 (13.7) years and mean (SD) disease duration of 15.3 (12.7) years. In a comparison with 482 ethnicity matched population-based controls, the D70 sequence exerted a strong protective effect (OR = 0.52, p<0.001) that remained significant when the SE at the same locus was accounted for (OR = 0.72, 95% CI 0.60 to 0.86, p<0.001). The SE assessed on all HLA-DRB1 serotypic backgrounds except DR1 was associated with RA susceptibility (additive OR = 2.43, p<0.001). Associations were found between SE and serum levels of rheumatoid factor (p<0.001, with correlation of 0.18) and anti-cyclic citrullinated peptide antibodies (p<0.001, with correlation of 0.25) but not with serum C-reactive protein. CONCLUSION: The D70 allele has a significant protective effect that is mitigated but still significant when the risk effect of the SE at the same locus is taken into account. The presence of the SE on DR4 is associated with greater RA susceptibility and certain disease-activity measures.
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Article Pyridoxine supplementation corrects vitamin B6 deficiency but does not improve inflammation in patients with rheumatoid arthritis. free! 2005
Chiang EP, Selhub J, Bagley PJ, Dallal G, Roubenoff R. · Department of Food Science and Biotechnology, National Chung-Hsing University, 250 Kuo-Kuang Road, Taichung, Taiwan 402, Republic of China. · Arthritis Res Ther. · Pubmed #16277693 links to free full text
Abstract: Patients with rheumatoid arthritis have subnormal vitamin B6 status, both quantitatively and functionally. Abnormal vitamin B6 status in rheumatoid arthritis has been associated with spontaneous tumor necrosis factor (TNF)-alpha production and markers of inflammation, including C-reactive protein and erythrocyte sedimentation rate. Impaired vitamin B6 status could be a result of inflammation, and these patients may have higher demand for vitamin B6. The aim of this study was to determine if daily supplementation with 50 mg of pyridoxine for 30 days can correct the static and/or the functional abnormalities of vitamin B6 status seen in patients with rheumatoid arthritis, and further investigate if pyridoxine supplementation has any effects on the pro-inflammatory cytokine TNF-alpha or IL-6 production of arthritis. This was a double-blinded, placebo-controlled study involving patients with rheumatoid arthritis with plasma pyridoxal 5'-phosphate below the 25th percentile of the Framingham Heart Cohort Study. Vitamin B6 status was assessed via plasma and erythrocyte pyridoxal 5'-phosphate concentrations, the erythrocyte aspartate aminotransferase activity coefficient (alphaEAST), net homocysteine increase in response to a methionine load test (DeltatHcy), and 24 h urinary xanthurenic acid (XA) excretion in response to a tryptophan load test. Urinary 4-pyridoxic acid (4-PA) was measured to examine the impact of pyridoxine treatment on vitamin B6 excretion in these patients. Pro-inflammatory cytokine (TNF-alpha and IL-6) production, C-reactive protein levels and the erythrocyte sedimentation rate before and after supplementation were also examined. Pyridoxine supplementation significantly improved plasma and erythrocyte pyridoxal 5'-phosphate concentrations, erythrocyte alphaEAST, urinary 4-PA, and XA excretion. These improvements were apparent regardless of baseline B6 levels. Pyridoxine supplementation also showed a trend (p < 0.09) towards a reduction in post-methionine load DeltatHcy. Supplementation did not affect pro-inflammatory cytokine production. Although pyridoxine supplementation did not suppress pro-inflammatory cytokine production in patients with rheumatoid arthritis, the suboptimal vitamin B6 status seen in rheumatoid arthritis can be corrected by 50 mg pyridoxine supplementation for 30 days. Data from the present study suggest that patients with rheumatoid arthritis may have higher requirements for vitamin B6 than those in a normal healthy population.
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Article Inflammation causes tissue-specific depletion of vitamin B6. free! 2005
Chiang EP, Smith DE, Selhub J, Dallal G, Wang YC, Roubenoff R. · Department of Food Science and Biotechnology, National Chung Hsing University, Taichung, Taiwan. · Arthritis Res Ther. · Pubmed #16277678 links to free full text
Abstract: Previously we observed strong and consistent associations between vitamin B6 status and several indicators of inflammation in patients with rheumatoid arthritis. Clinical indicators, including the disability score, the length of morning stiffness, and the degree of pain, and biochemical markers, including the erythrocyte sedimentation rate and C-reactive protein levels, were found to be inversely correlated with circulating vitamin B6 levels. Such strong associations imply that impaired vitamin B6 status in these patients results from inflammation. In the present study we examined whether inflammation directly alters vitamin B6 tissue contents and its excretion in vivo. A cross-sectional case-controlled human clinical trial was performed in parallel with experiments in an animal model of inflammation. Plasma and erythrocyte and pyridoxal 5'-phosphate concentrations, urinary 4-pyridoxic acid excretion, and the activity coefficient of erythrocyte aspartate aminotransferase were compared between patients and healthy subjects. Adjuvant arthritis was induced in rats for investigating hepatic and muscle contents as well as the urinary excretion of vitamin B6 during acute and chronic inflammation. Patients with rheumatoid arthritis had low plasma pyridoxal 5'-phosphate compared with healthy control subjects, but normal erythrocyte pyridoxal 5'-phosphate and urinary 4-pyridoxic acid excretion. Adjuvant arthritis in rats did not affect 4-pyridoxic acid excretion or muscle storage of pyridoxal 5'-phosphate, but it resulted in significantly lower pyridoxal 5'-phosphate levels in circulation and in liver during inflammation. Inflammation induced a tissue-specific depletion of vitamin B6. The low plasma pyridoxal 5'-phosphate levels seen in inflammation are unlikely to be due to insufficient intake or excessive vitamin B6 excretion. Possible causes of decreased levels of vitamin B6 are discussed.
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Article Use of mass spectrometry to identify protein biomarkers of disease severity in the synovial fluid and serum of patients with rheumatoid arthritis. free! 2004
Liao H, Wu J, Kuhn E, Chin W, Chang B, Jones MD, O'Neil S, Clauser KR, Karl J, Hasler F, Roubenoff R, Zolg W, Guild BC. · Millennium Pharmaceuticals, Inc., Cambridge, Massachusetts 02139, USA. · Arthritis Rheum. · Pubmed #15593230 links to free full text
Abstract: OBJECTIVE: To identify a panel of candidate protein biomarkers of rheumatoid arthritis (RA) that can predict which patients will develop erosive, disabling disease. METHODS: A 2-step proteomic approach was used for biomarker discovery and verification. In the first step, 2-dimensional liquid chromatography-coupled tandem mass spectrometry was used to generate protein profiles of synovial fluid (SF) from patients with either erosive RA (n = 5) or nonerosive RA (n = 5). In the second step, the selected candidate markers were verified using quantitative multiple reaction monitoring mass spectrometry in sera of patients with erosive RA (n = 15) or nonerosive RA (n = 15) and of healthy controls (n = 15). RESULTS: Through differential profiling of proteins in the <40-kd portion of the SF proteome, we selected 33 prospective candidate biomarkers from a total of 418 identified proteins. Among the proteins that were elevated in the SF of patients with erosive RA were C-reactive protein (CRP) and 6 members of the S100 protein family of calcium-binding proteins. Significantly, levels of CRP, S100A8 (calgranulin A), S100A9 (calgranulin B), and S100A12 (calgranulin C) proteins were also elevated in the serum of patients with erosive disease compared with patients with nonerosive RA or healthy individuals. CONCLUSION: Several potential protein marker candidates have been identified for prognosis of the erosive form of RA. This study demonstrates the facility of using protein mass spectrometry in SF and serum for global discovery and verification of clinically relevant sets of disease biomarkers.
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Article Tumor necrosis factor-alpha production is associated with less body cell mass in women with rheumatoid arthritis. 2004
Walsmith J, Abad L, Kehayias J, Roubenoff R. · Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, Massachusetts 02111, USA. · J Rheumatol. · Pubmed #14705214 No free full text.
Abstract: OBJECTIVE: To examine the relationship between inflammatory cytokine production and body cell mass (BCM) in women with stable, medically well-controlled rheumatoid arthritis (RA). METHODS: Case-control study of 20 women with RA and 20 healthy women matched for age, race, and body mass index (kg/m2). Tumor necrosis factor-alpha (TNF-alpha), interleukin 1beta (IL-1beta), and IL-6 production were measured by specific, non-cross-reacting ELISA of peripheral blood mononuclear cells (PBMC) cultured with and without 100 ng/ml of endotoxin. Total BCM was assessed by the reference method of whole-body counting of naturally occurring radioactive potassium-40. RESULTS: Patients with RA were cachectic, with 14% less BCM (p < 0.001) and higher TNF-alpha production (p < 0.05) than controls. TNF-alpha production was inversely associated with BCM both without (r = -0.51, p = 0.03) and with (r = -0.57, p = 0.01) endotoxin stimulation in patients but not in controls. In multivariate linear regression models, these inverse associations remained significant after adjustment for age and physical activity. No association was found for IL-1beta or IL-6 production in these models. CONCLUSION: Women with stable, medically well-controlled RA have lower than normal BCM that is inversely associated with elevated TNF-alpha production.
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Article Abnormal vitamin B(6) status is associated with severity of symptoms in patients with rheumatoid arthritis. 2003
Chiang EP, Bagley PJ, Selhub J, Nadeau M, Roubenoff R. · Vitamin Metabolism and Aging Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, 711 Washington Street, Boston, MA 02111, USA. · Am J Med. · Pubmed #12681455 No free full text.
Abstract: PURPOSE: Patients with rheumatoid arthritis have low plasma vitamin B(6) levels and elevated plasma homocysteine responses to a methionine load. We examined whether these abnormalities are associated with clinical and biochemical indicators of disease status. METHODS: We performed a cross-sectional study in 37 patients who met the American College of Rheumatology criteria for rheumatoid arthritis. Vitamin B(6) status was assessed by the plasma pyridoxal 5'-phosphate level and with the homocysteine response to a methionine load test. Clinical disease activity was assessed by joint counts, the Health Assessment Questionnaire disability score, and biochemical markers of the acute phase response. RESULTS: Plasma pyridoxal 5'-phosphate levels were inversely correlated with the erythrocyte sedimentation rate (r = -0.37, P = 0.02), C-reactive protein level (r = -0.52, P = 0.002), disability score (r = -0.37, P = 0.02), morning stiffness (r = -0.38, P = 0.02), and degree of pain (r = -0.33, P = 0.04). The increase in homocysteine levels after a methionine load correlated with the erythrocyte sedimentation rate (r = 0.39, P = 0.02), C-reactive protein level (r = 0.37, P = 0.03), disability score (r = 0.37, P = 0.04), degree of pain (r = 0.38, P = 0.02) and fatigue (r = 0.42, P = 0.01), number of painful joints (r = 0.43, P = 0.007), and number of swollen joints (r = 0.32, P = 0.05). CONCLUSION: Markers of vitamin B(6) status are associated with disease activity and severity, synovial burden, and pain in patients with rheumatoid arthritis, raising the possibility that impaired vitamin B(6) status in these patients is a result of inflammation.
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Article Plasma pyridoxal 5'-phosphate concentration is correlated with functional vitamin B-6 indices in patients with rheumatoid arthritis and marginal vitamin B-6 status. free! 2003
Chiang EP, Bagley PJ, Roubenoff R, Nadeau M, Selhub J. · Vitamin Metabolism and Aging Laboratory, Jean Mayer U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA. · J Nutr. · Pubmed #12672918 links to free full text
Abstract: Many patients with rheumatoid arthritis (RA) have low plasma pyridoxal-phosphate (PLP) but a normal erythrocyte aspartate aminotransferase activity coefficient (alpha EAST), a measure of vitamin B-6 status in the erythrocytes, compared with healthy subjects. The goal of the present study was to examine the correlations of PLP levels in these two compartments (plasma and erythrocytes) with other established indices of vitamin B-6 status, and to determine which indicator better reflects functional status of vitamin B-6 in patients with RA. Multiple indices of vitamin B-6 status were measured in 33 patients with RA. Plasma PLP, urinary 4-pyridoxic acid (4-PA), net increase in plasma total homocysteine after a methionine load (DeltatHcy) and net increase in urinary xanthurenic acid after a tryptophan load (DeltaXA) were log-transformed to reach normality for statistical analyses. We found that log-plasma PLP levels were inversely correlated with both log-DeltatHcy (r = -0.368, P = 0.035) and log-DeltaXA (r = -0.333, P = 0.05). Plasma PLP was not correlated with alpha EAST or urinary 4-PA excretion. In contrast, erythrocyte PLP was inversely correlated with alpha EAST (r = -0.431, P = 0.012) and positively correlated with log-4-PA (r = 0.475, P = 0.005), but erythrocyte PLP was not correlated with the outcomes of a methionine or tryptophan load test. Erythrocyte PLP and log-4-PA, but not plasma PLP, were correlated with dietary intake of vitamin B-6 after adjusting for protein intake (r = 0.420, P = 0.015 and r = 0.333, P = 0.05, respectively). We suggest that in patients with RA, plasma PLP levels are a better diagnostic indicator of functional vitamin B-6 status than erythrocyte PLP levels.
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Article Cachexia in rheumatoid arthritis is not explained by decreased growth hormone secretion. free! 2002
Rall LC, Walsmith JM, Snydman L, Reichlin S, Veldhuis JD, Kehayias JJ, Abad LW, Lundgren NT, Roubenoff R. · Nutrition Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, 711 Washington Street, Boston, MA 02111, USA. · Arthritis Rheum. · Pubmed #12384914 links to free full text
Abstract: OBJECTIVE: Patients with rheumatoid arthritis (RA) lose body cell mass (BCM) by unknown mechanisms. Since the loss of BCM in normal aging individuals parallels the characteristic age-related decline in growth hormone (GH) secretion, this study was carried out to determine whether further decreased GH secretion plays a role in the pathogenesis of this loss of BCM in RA patients, termed "rheumatoid cachexia." METHODS: GH secretory kinetics were determined by deconvolution analysis in 16 patients with RA and 17 healthy controls matched for age (mean +/- SD 45.4 +/- 13.2 years and 47.1 +/- 14.6 years, respectively), sex, race, and body mass index. Blood samples were obtained every 20 minutes for 24 hours. Body composition was ascertained using total-body potassium (TBK) as a measure of BCM and dual x-ray absorptiometry to determine fat mass. RESULTS: BCM was reduced in patients with RA compared with healthy controls (mean +/- SD gm TBK 79.5 +/- 9.5 versus 94.9 +/- 11.9; P < 0.0005), but there was no difference in fat mass. GH kinetic parameters in patients with RA did not differ from those in controls. CONCLUSION: These findings suggest that GH kinetics are unaltered in RA patients compared with healthy subjects; thus, GH deficiency does not account for rheumatoid cachexia.
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Article Low physical activity reduces total energy expenditure in women with rheumatoid arthritis: implications for dietary intake recommendations. free! 2002
Roubenoff R, Walsmith J, Lundgren N, Snydman L, Dolnikowski GJ, Roberts S. · Nutrition, Exercise Physiology, and Sarcopenia Laboratory, Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA. · Am J Clin Nutr. · Pubmed #12324290 links to free full text
Abstract: BACKGROUND: Rheumatoid arthritis (RA) causes cachexia, a metabolic response characterized by loss of muscle mass and elevated resting energy expenditure (REE). However, energy expenditure in physical activity in subjects with RA is lower than that in healthy subjects. It is not known which effect predominates in regulating total energy expenditure (TEE), and thus whether the dietary energy requirements of subjects with RA are higher or lower than those of healthy subjects. OBJECTIVE: Our objective was to determine TEE in women with RA by using the reference method of doubly labeled water ((2)H(2)(18)O). DESIGN: In this case-control study, we examined 20 women with RA and 20 healthy women who were matched for age and body mass index. RESULTS: The patients with RA were cachectic (their body cell mass was 14% lower than that of the controls, P < 0.001), but REE was not elevated, reflecting good disease control. Mean (+/- SD) TEE was 1344 kJ/d lower in the patients than in the controls (9133 +/- 1335 compared with 10 477 +/- 1992 kJ/d; P < 0.02). The energy expenditure in physical activity of the patients was 1034 kJ/d lower than that of the controls (P < 0.04), which accounted for 77% of the difference in TEE between the 2 groups. The physical activity level (TEE/REE) of the patients also tended to be lower than that of the controls (1.70 +/- 0.24 compared with 1.89 +/- 0.36; P < 0.07). CONCLUSION: A low physical activity level is the main determinant of lower-than-normal TEE, and thus energy requirements, in women with RA.
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Article Cachexia in rheumatoid arthritis. 2002
Walsmith J, Roubenoff R. · Nutrition, Exercise Physiology, and Sarcopenia Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA. · Int J Cardiol. · Pubmed #12163213 No free full text.
Abstract: Rheumatoid arthritis is a debilitating, chronic, systemic, autoimmune disease of unknown etiology that causes destruction of joint cartilage and bone. It generally occurs between the fourth and sixth decades of life, and affects two to three times more women than men. It is characterized by joint stiffness, pain, and swelling, and is accompanied by a loss of body cell mass. This loss of cell mass, known as rheumatoid cachexia, predominates in skeletal muscle, but also occurs in the viscera and immune system. Thus, rheumatoid cachexia leads to muscle weakness and a loss of functional capacity, and is believed to accelerate morbidity and mortality in rheumatoid arthritis. Currently there is no established mechanism for rheumatoid cachexia, but it is accompanied by elevated resting energy expenditure, accelerated whole-body protein catabolism, and excess production of the inflammatory cytokines, tumor necrosis factor-alpha and interleukin-1beta. Tumor necrosis factor-alpha is probably the central mediator of muscle wasting in rheumatoid arthritis, and is known to act synergistically with interleukin-1beta to promote cachexia. In general, tumor necrosis factor-alpha and interleukin-1beta are thought to alter the balance between protein degradation and protein synthesis in rheumatoid arthritis to cause muscle wasting. The precise mechanism by which they do this is not known. Reduced peripheral insulin action and low habitual physical activity are important consequences of rheumatoid arthritis, and have also been implicated as mediators of rheumatoid cachexia. Insulin inhibits muscle protein degradation. Consequently, reduced peripheral insulin action in rheumatoid arthritis is thought to be permissive to cytokine-driven muscle loss. The cause of reduced peripheral insulin action in rheumatoid arthritis is not known, but tumor necrosis factor-alpha has been shown to interfere with insulin receptor signaling and is probably an important contributor. Low habitual physical activity has consistently been observed in rheumatoid arthritis and is an important consequence of, and contributor to, muscle wasting. In addition, low physical activity predisposes to fat gain and is believed to precipitate a negative reinforcing cycle of muscle loss, reduced physical function, and fat gain in rheumatoid arthritis, which leads to 'cachectic obesity'. To date, there is no standard treatment for rheumatoid cachexia. However, physical exercise is currently believed to be the most important and clinically relevant countermeasure against rheumatoid cachexia. In general, a combination of skeletal muscle strength training and aerobic exercise is recommended, but must be prescribed with the patient's disease status, overall health, and safety in mind. Future studies should investigate the safety, efficacy, and required dose of anti-cytokine therapy for the treatment of rheumatoid cachexia. In this review, we outline the current definition of rheumatoid cachexia, and discuss the etiology, pathogenesis, and treatment of rheumatoid cachexia.
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Minor Biological significance of anti-cyclic citrullinated peptide antibody in rheumatoid arthritis. free! 2008
Roubenoff R, Beckman E, Weinblatt M, Shadick N, Gregersen PK. · No affiliation provided · Ann Intern Med. · Pubmed #18316760 links to free full text
This publication has no abstract.
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