Rheumatoid Arthritis: Weinmann P

Caetano-Lopes J, Henriques R, Canhão H, Duarte J, Amaral PM, Vale M, Moura RA, Pereira PA, Weinmann P, Abdulghani S, Souto-Carneiro M, Rego P, Monteiro J, Sakagushi S, Queiroz MV, Konttinen YT, Graça L, Vaz MF, Fonseca JE. · Rheumatology Research Unit, Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal. · Clin Exp Rheumatol. · Pubmed #19604441 No free full text.

Abstract: OBJECTIVES:Rheumatoid arthritis (RA) is associated with an increased risk of fragility fractures. In RA patients, the direct effect of inflammation on bone is difficult to study because their skeleton is also affected by medication with corticosteroids and other drugs as well as aging and menopause, which contribute to bone fragility. This study used an animal model of chronic arthritis to evaluate the direct impact of chronic inflammation on biomechanical properties and structure of bone.METHODS:In the SKG mouse chronic arthritis model three point bending tests were performed on femoral bones and compression tests on vertebral bodies. Collagen structure was analysed using second-harmonic generation (SHG) imaging with a two-photon microscope, ultramorphology by scanning electron microscopy (SEM) coupled with energy dispersive x-ray spectroscopy (EDS) and bone density using water pycnometer.RESULTS:Arthritic bones had poor biomechanical quality compared to control bones. SHG, SEM and pycnometry disclosed variable signs of impaired collagen organization, poor trabecular architecture and low bone density.CONCLUSION:Present data demonstrate for the first time that chronic inflammation per se, without confounding influence of drugs and aging, leads to impairment of bone biomechanics in terms of stiffness, ductility and ultimate strength (fracture).

Weinmann P, Moura RA, Caetano-Lopes JR, Pereira PA, Canhão H, Queiroz MV, Fonseca JE. · Rheumatology Research Unit, Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal. · Clin Exp Rheumatol. · Pubmed #18173925 No free full text.

Abstract: OBJECTIVES: To analyse the activation state and apoptosis of circulating neutrophils in untreated very early rheumatoid arthritis (VERA) and after exposure to low dose corticosteroids and methotrexate (MTX). METHODS: Neutrophils were isolated from the peripheral blood of VERA patients at 3 different times: before any treatment was started, 2 weeks after starting a low dose of prednisone (5-10 mg) and 4 months after reaching more than 20mg/week of MTX. The expression of different activation markers (CD11b, CD64, CD86 and CD69) in freshly isolated neutrophils was analysed by flow cytometry. Apoptosis was measured by the loss of DNA content, which was analysed by flow cytometry using propidium iodide. RESULTS: Compared to neutrophils from healthy controls, we have found a delayed neutrophil apoptosis within 6 h and 22 h of cultured polymorphonuclear leukocytes (PMN) derived from VERA patients without any treatment or treated with corticosteroids. The delay of PMN apoptosis was restored to control levels after treatment with MTX. CONCLUSION: The treatment of VERA patients with corticosteroids did not affect the delay of neutrophil apoptosis. However, delayed apoptosis was restored to control levels after treatment with low dose MTX, which highlights the importance of early RA treatment with MTX.

Fonseca JE, Cavaleiro J, Teles J, Sousa E, Andreozzi VL, Antunes M, Amaral-Turkman MA, Canhão H, Mourão AF, Lopes J, Caetano-Lopes J, Weinmann P, Sobral M, Nero P, Saavedra MJ, Malcata A, Cruz M, Melo R, Braña A, Miranda L, Patto JV, Barcelos A, da Silva JC, Santos LM, Figueiredo G, Rodrigues M, Jesus H, Quintal A, Carvalho T, da Silva JA, Branco J, Queiroz MV. · Rheumatology Research Unit, Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av, Professor Egas Moniz, 1649-028, Lisboa, Portugal. · Arthritis Res Ther. · Pubmed #17408492 links to  free full text

Abstract: The objective of this study was to assess whether clinical measures of rheumatoid arthritis activity and severity were influenced by tumor necrosis factor-alpha (TNF-alpha) promoter genotype/haplotype markers. Each patient's disease activity was assessed by the disease activity score using 28 joint counts (DAS28) and functional capacity by the Health Assessment Questionnaire (HAQ) score. Systemic manifestations, radiological damage evaluated by the Sharp/van der Heijde (SvdH) score, disease-modifying anti-rheumatic drug use, joint surgeries, and work disability were also assessed. The promoter region of the TNF-alpha gene, between nucleotides -1,318 and +49, was sequenced using an automated platform. Five hundred fifty-four patients were evaluated and genotyped for 10 single-nucleotide polymorphism (SNP) markers, but 5 of these markers were excluded due to failure to fall within Hardy-Weinberg equilibrium or to monomorphism. Patients with more than 10 years of disease duration (DD) presented significant associations between the -857 SNP and systemic manifestations, as well as joint surgeries. Associations were also found between the -308 SNP and work disability in patients with more than 2 years of DD and radiological damage in patients with less than 10 years of DD. A borderline effect was found between the -238 SNP and HAQ score and radiological damage in patients with 2 to 10 years of DD. An association was also found between haplotypes and the SvdH score for those with more than 10 years of DD. An association was found between some TNF-alpha promoter SNPs and systemic manifestations, radiological progression, HAQ score, work disability, and joint surgeries, particularly in some classes of DD and between haplotypes and radiological progression for those with more than 10 years of DD.