血清软骨寡聚基质蛋白(COMP)检测在银屑病性关节炎患者中的意义研究

目的:探讨银屑病性关节炎(PSA)患者血清软骨寡聚基质蛋白(COMP)水平变化及其对放射学改变的早期预测价值。方法:采用ELISA方法测定并对比分析22例银屑病性关节炎(PSA)与对照组及正常人血清中COMP的水平的差异,部分PSA患者各项临床指标及两年后关节放射学改良SHARP(vdH-Sharp)指数评分与COMP行相关性分析。结果:与仅有滑膜损害的其他关节炎患者及正常人群比较,PSA患者血清COMP显著升高(P<0.05)。PSA患者2年随访发现COMP与患者关节X线的改良SHARP评分前后差值呈正相关(P=0.01,r=0.754)COMP与初诊时的血沉(ESR)、C反应蛋白(CRP)、关节肿胀、压痛指数相关(P<0.05)。结论:COMP在PSA患者血清中异常增高,提示其可为PSA软骨病变早期诊断及判断软骨病变进展、预后和治疗效果的一项理想指标。     

Serum or plasma cartilage oligomeric matrix protein concentration as a diagnostic marker in pseudoachondroplasia: differential diagnosis of a family

Pseudoachondroplasia (PSACH) is an autosomal-dominant osteochondrodysplasia due to mutations in the gene encoding cartilage oligomeric matrix protein (COMP). Clinical diagnosis of PSACH is based primarily on family history, physical examination, and radiographic evaluation, and is sometimes extremely difficult, particularly in adult patients. Genetic diagnosis based on DNA sequencing, on the other hand, can be expensive, time-consuming, and intensive because COMP mutations may be scattered throughout the gene. However, there is evidence that decreased plasma COMP concentration may serve as a diagnostic marker in PSACH, particularly in adult patients. Here, we report the serum and/or plasma COMP concentration-based differential diagnosis of a family with affected adult members. The mean serum and/or plasma COMP concentrations of the three affected family members alive (0.69+/-0.15 and/or 0.81+/-0.08 microg/ml, respectively) were significantly lower than those of an age-compatible control group of 21 adults (1.52+/-0.37 and/or 1.37+/-0.36 microg/ml, respectively; P<0.0001). Bidirectional fluorescent DNA sequencing-based genetic diagnosis of these patients revealed a heterozygous mutation for the nucleotide change 1532A>G in exon 14 of the COMP gene, resulting in a substitution of amino acid 511 from aspartic acid to glycine in COMP. Thus, serum and/or plasma COMP concentration may be suggested as an additional diagnostic marker to aid clinical and radiographic findings in suspected cases of PSACH.     

Expression of extracellular matrix molecules typical of articular cartilage in the human scapholunate interosseous ligament

The scapholunate interosseous ligament (SLIL) connects the scaphoid and lunate bones and plays a crucial role in carpal kinematics. Its rupture leads to carpal instability and impairment of radiocarpal joint function. As the ligament is one of the first structures affected in rheumatoid arthritis, we conducted an immunohistochemical study of cadaveric tissue to determine whether it contains known autoantigens for rheumatoid arthritis. We immunolabelled the ligament from one hand in 12 cadavers with monoclonal antibodies directed against a wide range of extracellular matrix (ECM) molecules associated with both fibrous and cartilaginous tissues. The labelling profile has also enabled us to comment on how the molecular composition of the ligament relates to its mechanical function. All regions of the ligament labelled for types I, III and VI collagens, chondroitin 4 and 6 sulphates, keratan sulphate, dermatan sulphate, versican, tenascin and cartilage oligomeric matrix protein (COMP). However, both entheses labelled strongly for type II collagen, aggrecan and link protein and were distinctly fibrocartilaginous. In some regions, the ligament attached to bone via a region of hyaline cartilage that was continuous with articular cartilage. Labelling for cartilage molecules in the midsubstance was most evident dorsally. We conclude that the SLIL has an ECM which is typical of other highly fibrocartilaginous ligaments that experience both tensile load and shear. The presence of aggrecan, link protein, COMP and type II collagen could explain why the ligament may be a target for autoantigenic destruction in some forms of rheumatoid arthritis.     

Different mechanical loading protocols influence serum cartilage oligomeric matrix protein levels in young healthy humans

The purpose of the study was to investigate whether a relationship between the loading mode of physical activity and serum cartilage oligomeric matrix protein (COMP) concentration exists and whether the lymphatic system contributes to COMP release into the serum. Serum COMP levels were determined in healthy male subjects before, after and at 18 further time points within 7 h at four separate experimental days with four different loading interventions. The loading intervention included high impact running exercise, slow but deep knee bends, and lymphatic drainage of 30 min duration, respectively, and a resting protocol. The serum COMP levels were measured using a commercially available quantitative enzyme-linked immunosorbent assay. An increase (p < 0.001) in serum COMP concentration was detected immediately after 30 min running exercise. Slow but deep knee bends did not cause any significant changes in serum COMP levels. Lymphatic drainage also had no effect on the serum COMP concentration. After 30 min of complete rest the serum COMP level was significantly (p = 0.008) reduced. The elevation of COMP serum concentration seems to depend on the loading mode of the physical activity and to reflect the extrusion of COMP fragments from the impact loaded articular cartilage or synovial fluid.     

Inflammation and bone erosion are suppressed in models of rheumatoid arthritis following treatment with a novel Syk inhibitor

Spleen tyrosine kinase (Syk), a key mediator of immunoreceptor signaling in inflammatory cells, is essential for immune complex-mediated signal transduction initiated by activated receptors for immunoglobulin G. In collagen-induced arthritis, R788/R406, a novel and potent small molecule Syk inhibitor suppressed clinical arthritis, bone erosions, pannus formation, and synovitis. Serum anti-collagen type II antibody levels were unaltered, while the half-life of exogenous antibody was extended when co-administered with R406. Expression of the targeted kinase (Syk) in synovial tissue correlated with the joint level of inflammatory cell infiltrates and was virtually undetectable in treated rats. Syk inhibition suppressed synovial cytokines and cartilage oligomeric matrix protein (COMP) in serum, suggesting a sensitive and reliable biomarker for R406 activity. These results highlight the role of activating Fcgamma receptors in inflammatory synovitis and suggest that interruption of the signaling cascade with a novel Syk inhibitor may be a useful addition to immunosuppressive disease-modifying anti-rheumatic drugs currently used in the treatment of human autoimmune diseases such as rheumatoid arthritis.     

Remarkable improvement of the hip joint lesion in a patient with rheumatoid arthritis by the treatment with anti-TNF-α agents

22-year old woman who was previously diagnosed as having juvenile idiopathic arthritis (JIA) was treated with anti-TNF-α agents. Her disease activity was assessed as Stage IV and Class III by Steinbrocker's classification and resistant to steroids and methotrexate. Initially clinical findings responded well to infliximab (IFX), but polyarthritis recurred 15 months after the start of the treatment, and IFX was switched to etanercept (ETN) with good response. On the other hand, effects on the osteoarticular lesions were continuously observed through the period of the treatment with these two biologics. It was thought very rare that weight-bearing joint like the hip joint was restored as was seen in this case, while its mechanism is unknown. Because mechanism for inhibition of inflammation or joint destruction might be independent, we should investigate further the relationship between inflammation and joint destruction in the future.     

Cell and matrix modulation in prenatal and postnatal equine growth cartilage,zones of Ranvier and articular cartilage

Formation of synovial joints includes phenotypic changes of the chondrocytes and the organisation of their extracellular matrix is regulated by different factors and signalling pathways. Increased knowledge of the normal processes involved in joint development may be used to identify similar regulatory mechanisms during pathological conditions in the joint. Samples of the distal radius were collected from prenatal and postnatal equine growth plates, zones of Ranvier and articular cartilage with the aim of identifying Notch signalling components and cells with stem cell-like characteristics and to follow changes in matrix protein localisation during joint development. The localisation of the Notch signalling components Notch1, Delta4, Hes1, Notch dysregulating protein epidermal growth factor-like domain 7 (EGFL7), the stem cell-indicating factor Stro-1 and the matrix molecules cartilage oligomeric matrix protein (COMP), fibromodulin, matrilin-1 and chondroadherin were studied using immunohistochemistry. Spatial changes in protein localisations during cartilage maturation were observed for Notch signalling components and matrix molecules, with increased pericellular localisation indicating new synthesis and involvement of these proteins in the formation of the joint. However, it was not possible to characterise the phenotype of the chondrocytes based on their surrounding matrix during normal chondrogenesis. The zone of Ranvier was identified in all horses and characterised as an area expressing Stro-1, EGFL7 and chondroadherin with an absence of COMP and Notch signalling. Stro-1 was also present in cells close to the perichondrium, in the articular cartilage and in the fetal resting zone, indicating stem cell-like characteristics of these cells. The presence of stem cells in the articular cartilage will be of importance for the repair of damaged cartilage. Perivascular chondrocytes and hypertrophic cells of the cartilage bone interface displayed positive staining for EGFL7, which is a novel finding and suggests a role of EGFL7 in the vascular infiltration of growth cartilage.     

COMP (cartilage oligomeric matrix protein) is synthesized in ligament, tendon, meniscus, and articular cartilage

The presence of cartilage oligomeric matrix protein (COMP) in extracts of ligament, tendon, meniscus, and canine articular cartilage was demonstrated by Western blot analysis using anti-dog COMP antibody. When the tissues were cultured in the presence of [35-S]methionine/cysteine, metabolically labeled COMP was purified from the culture media and from tissue extracts by DEAE-cellulose gel chromatography. SDS-Polyacrylamide gel electrophoresis (SDS-PAGE) followed by autoradiography and immunoblotting under reducing and non-reducing conditions revealed that COMP is synthesized by the cells of these connective tissues. Increased levels of COMP in samples of both synovial fluid and serum of patients with various joint diseases may not only be derived from cartilage but also from ligaments and tendons. COMP is not a highly tissue-specific cartilage molecule.     

Matrix metalloproteinase (MMP)-3 is not effective for evaluating hemophilic arthropathy

Serum matrix metalloproteinase (MMP) 3 is a marker that is directly associated with the joint cartilage destruction. In cases of rheumatoid arthritis (RA), serum MMP-3 increases as the synovium becomes inflamed, which is one of the causal factors of joint destruction. Similarly, it may increase even in hemophilic arthropathy, thereby causing inflammation of the synovium. In order to determine whether MMP-3 can act as an indicator of arthrosis in hemophilic arthropathy, we evaluated serum MMP-3 in terms of patients' subjective symptoms of hemophilic arthropathy. 56 patients with mild to severe hemophilia were enrolled. We asked the patients to score the subjective joint mobility of 12 joints by using survey sheets of the joints. Symptoms for each joint were scored from 0 to 2 points (0: no symptoms, 1: minor difficulties, 2: difficulties). The maximum of joint score was 18 points, and the mean +/- SD was 5.1 +/- 4.7 points. The average of serum MMP-3 was 74.2 +/- 38.6 ng/ml, and only 5 cases exceeded the upper end of reference value of 121.0 ng/ml. The average joint score in the 5 cases was 6.8 points, which was slightly higher than the average (4.9 points) of the other cases. However, there was no statistical significant correlations between MMP-3 and the joint score. Also, there was no significant difference in serum MMP-3 between severity of hemophilia, symptom of bleeding and HIV positivity, respectively. In conclusion, these results suggested that serum MMP-3 was not useful for evaluating hemophilic arthropathy.     

Advanced glycation end-product levels in subtotally nephrectomized rats: beneficial effects of angiotensin II receptor 1 antagonist losartan

The angiotensin II receptor 1 antagonist losartan (L) inhibited the advanced glycated end-products (AGEs) induced expression of transforming growth factor beta(1) in in vitro experiments performed on renal tubuloepithelial cells. To test the pathophysiological importance of these findings, the possible link between serum AGEs levels and angiotensin system was investigated in the model of normotensive subtotally nephrectomized rats(4/6-NX). Concentration of AGEs in serum of placebo administered 4/6-NX rats (n = 7, 1.09+/-0.09 U/l) increased slightly in comparison with sham-operated healthy controls (CTRL, n = 8, 0.94+/-0.10 U/l, p<0.02) as measured by competitive ELISA. Treatment of 4/6-NX rats with L over 12 weeks ameliorated the rise in serum AGEs concentration (1.00+/-0.12 U/l, n = 15 <0.005) almost to the level observed for CTRL. This effect was further corroborated by the observation, that the impaired renal excretion of AGEs in 4/6-NX-placebo rats (0.07+/-0.02 U/micromol creatinine) was significantly restored by L (0.09+/-0.02 U/micromol creatinine, <0.009) and resembled that of the CTRL (0.10+/-0.03 U/micromol creatinine). Administration of L to 4/6-NX rats significantly improved renal function as evaluated by a smaller rise in serum creatinine and urea concentration. In spite of the improvement in renal function, there were no differences in concentrations of transforming growth factor beta(1) in serum and in urine among the two groups. These effects were independent of blood pressure. Our data give first evidence, that long-term treatment with angiotensin II receptor 1 antagonist may exert salutary effects on AGEs levels in the rat remnant kidney model, probably due to improved renal function.     

Effect of acid-base alterations on hepatic lactate utilization

1. The effect of acid-base changes on hepatic lactate utilization was investigated in anaesthetized, mechanically ventilated dogs.2. Portal vein flow and hepatic artery flow were measured with electromagnetic flowmeters, lactate concentration of portal vein, arterial and mixed hepatic venous blood was determined by an enzymatic technique, and hepatic lactate uptake was calculated using the Fick principle.3. Respiratory alkalosis (Delta pH 0.25 +/- 0.02) in four dogs resulted in a significant fall in total hepatic blood flow (-22 +/- 4%) and a significant rise in both arterial lactate concentration (2.18 +/- 0.32 m-mole/l.) and hepatic lactate utilization (3.9 +/- 1.2 mumole/min.kg).4. 0.6 M-Tris buffer infusion (Delta pH 0.21 +/- 0.02) in four dogs produced no significant changes in liver blood flow, arterial lactate concentration or hepatic lactate uptake.5. Respiratory acidosis (Delta pH -0.20 +/- 0.03) in six dogs and metabolic acidosis (Delta pH -0.20 +/- 0.02) in four dogs produced no significant changes in liver blood flow, decreases in arterial lactate concentration of 0.38 +/- 0.09 m-mole/l. (P < 0.05) and 0.13 +/- 0.13 m-mole/l., respectively, and no significant changes in hepatic lactate uptake.6. A significant correlation (r = 0.63; P < 0.01) was found between hepatic lactate utilization and arterial lactate concentration during the hyperlactataemia associated with respiratory alkalosis.7. Hyperlactataemia induced in four dogs by infusion of buffered sodium lactate (Delta pH 0.05 +/- 0.01;% Delta liver blood flow 29 +/- 7%) was also significantly correlated with hepatic lactate utilization (r = 0.70; P < 0.01) and the slope of the regression was similar to that during respiratory alkalosis.8. These data suggest that the hyperlactataemia of alkalosis is not due to impaired hepatic utilization of lactate and that the principal determinant of hepatic lactate uptake during alkalosis or lactate infusion is blood lactate concentration, rather than liver blood flow or acid-base status.     

Adenosine abolishes MTX-induced suppression of osteoclastogenesis and inflammatory bone destruction in adjuvant-induced arthritis

Methotrexate (MTX) is widely utilized for the treatment of patients with rheumatoid arthritis (RA); however, recent observation of the MTX-resistant patients proposed some difficulty in MTX-dependent therapeutic approach for RA. To access cellular events related to MTX resistance in RA in respect to inflammatory bone destruction, we investigated on an involvement of the potent inflammatory mediator adenosine in the regulation of osteoclastogenesis and inflammatory bone destruction. In rats with adjuvant-induced arthritis (AA rats), MTX efficiently suppressed bone destruction when it was administrated within 3 days after adjuvant injection, while it could not suppress inflammatory bone destruction if MTX was injected at the time of onset of inflammation (at day 10 after adjuvant injection). Time-course change in the level of plasma adenosine of AA rats was estimated by use of high-performance liquid chromatography and elucidated that adenosine level was markedly elevated till 10 days after adjuvant injection. In vitro bone marrow culture system for evaluating osteoclastogenesis, MTX markedly suppressed osteoclastogenesis in a stromal cell-dependent manner. This MTX-induced suppression of osteoclastogenesis was abrogated by the addition of adenosine. MTX suppressed the expression of mRNA for the receptor activator NF-κB ligand (RANKL), but it did not suppress the expression of osteoprotegerin (OPG). The addition of MTX and adenosine together markedly suppressed the level of OPG expression. Abolishment of MTX action by adenosine was significantly blocked by MRS1754, a highly selective antagonist for the A(2b) adenosine receptor (A(2b)AR), but not by caffeine, an antagonist for A?, A(2a), A? AR (A?AR, A(2a)AR, and A?AR), which suggests that adenosine acts through A(2b)AR. Immunohistochemical studies showed abundant expression of A(2b)AR in cells localized in the bone-bone marrow boundary of the distal tibia in AA rats but not in control rats. When adenosine was injected in the ankle joints of MTX-treated AA rats, the suppressive effects of MTX on bone destruction was abolished. The current data therefore suggest that upregulation of adenosine production abolished the suppressive effect of MTX on osteoclastic bone destruction. Involvement of the adenosine-A(2b)AR system may explain MTX resistance in RA.     

In vivo methotrexate kinetics and metabolism in human hematopoietic cells. Clinical significance of methotrexate concentrations in erythrocytes

The author has performed in vivo investigations of the methotrexate (MTX) accumulation, kinetics and polyglutamate metabolism in erythrocytes, neutrophils and myeloid bone marrow cells during clinical MTX therapy of patients with acute lymphoblastic leukemia (ALL), non-Hodgkin lymphoma and psoriasis. On the basis of these studies the clinical applicability of monitoring erythrocyte MTX concentrations in children with ALL and adult psoriasis patients have been evaluated. To accomplish this task a set of methods has been developed: 1) An automated enzymatic assay adapted for a centrifugal analyzer was used to measure MTX concentrations between 10 and 60 nmol/l in erythrocytes and serum. 2) For the study of MTX kinetics in myeloid cells, age fractionated erythrocytes and HPLC fractionated methotrexate polyglutamates a sequential radioligand binding assay with a range of 1-8 (and 1-16) nmol/l was employed. 3) Discontinuous Percoll gradients of increasing densities were used to separate myeloid cells and erythrocytes of increasing mean cell age. Declining reticulocyte counts and erythrocyte-aspartate aminotransferase activity were taken as parameters of increasing mean erythrocyte age. 4) In order to study MTX polyglutamate metabolism a high performance liquid chromatography (HPLC) procedure was set up using tetrabutylammonium phosphate in acetonitrile in an automatically generated gradient buffer system. The MTX polyglutamates were separated, and the concentrations determined by the radioligand binding assay. The individual polyglutamates were identified by comparisons with the retention times of MTX polyglutamate standards (MTX-glu1+2+3+4+6+7) which were detected spectrophotometrically at 304 nm. During 24 hour infusions MTX was incorporated predominantly in the proliferating myeloid bone marrow cells before appearing in circulating neutrophils about seven days later. Evidence for MTX incorporation in the erythroid precursors of the bone marrow was provided by demonstrating high MTX content in density fractionated reticulocyte enriched erythrocyte populations. During weekly low dose MTX treatment the erythrocyte MTX concentration reached a constant level (steady state ery-MTX) after 4-6 weeks. MTX concentrations in age fractionated red blood cells and the terminal decline of the ery-MTX and its polyglutamate forms after cessation of MTX administration revealed that maintenance of the steady state ery-MTX depended on three conditions: 1) The amount of MTX added to the circulation via MTX containing reticulocytes. 2) The in vivo efflux of MTX from circulating erythrocytes, and 3) The loss of MTX with age dependent destruction of red blood cells. The in vivo efflux of MTX accounted for a loss of MTX which was 3-4 times greater than the amount that was lost with age dependent erythrocyte destruction.(ABSTRACT TRUNCATED AT 400 WORDS)     

FcgammaRI up-regulation induced by local adenoviral-mediated interferon-gamma production aggravates chondrocyte death during immune complex-mediated arthritis

Using various FcgammaR-deficient mice, we have obtained suggestive evidence that FcgammaRI on macrophages is responsible for severe cartilage destruction during arthritis mediated by immune complexes (ICs). This role of FcgammaRI is pronounced in the presence of activated Th1 cells and a likely Th1 cell-derived cytokine mediating up-regulation of FcgammaRI expression is interferon (IFN)-gamma. We now investigated whether local overexpression of IFN-gamma using an adenoviral vector is able to elevate cartilage destruction during experimental immune complex-mediated arthritis (ICA) and to what extent this process is FcgammaRI-mediated. IFN-gamma overexpression during ICA had no significant effect on the total cell mass infiltrating the knee joint. However, a higher percentage of macrophages expressing markers for a proinflammatory phenotype was found and these macrophages were situated in close proximity of the cartilage surface. Interestingly, cartilage destruction as studied by matrix metalloproteinase (MMP)-mediated proteoglycan damage (VDIPEN expression), chondrocyte death, and erosion was significantly increased. This effect of IFN-gamma was only found in the presence of ICs, as IFN-gamma overexpression during zymosan-induced arthritis, which is not IC-dependent, did not lead to severe cartilage destruction. These results imply a crucial role for ICs and the IgG-binding receptors in the aggravation of cartilage damage by IFN-gamma. Local overexpression of IFN-gamma induced increased FcgammaRI mRNA levels in synovium. To study whether this up-regulation of FcgammaRI mediates aggravation of cartilage destruction, ICA was raised in FcgammaRI(-/-) and their wild-type controls. IFN-gamma resulted in elevated VDIPEN expression, which was still present in FcgammaRI(-/-). Of great interest, chondrocyte death remained low in FcgammaRI(-/-). These results indicate that IFN-gamma overexpression deteriorates cartilage destruction in the presence of ICs and that FcgammaRI is crucial in the development of chondrocyte death.     

Alleviation of rheumatoid arthritis by cell-transducible methotrexate upon transcutaneous delivery

Rheumatoid arthritis (RA) is a systemic autoimmune disease that is initiated and maintained by various inflammatory/immune cells and their cytokines, leading to cartilage degradation and bone erosion. Despite its potent therapeutic efficacy on RA, the oral administration of methotrexate (MTX) provokes serious adverse systemic complications, thus necessitating the local application of MTX. Here, we show that transcutaneous MTX (TC-MTX) can efficiently penetrate joint skin ex vivo and in vivo, and that TC-MTX can significantly improve the various inflammatory symptoms associated with RA. Further, TC-MTX preserved the joint-structures in mice with collagen-induced arthritis (CIA), which was also confirmed by three-dimensional micro-computed tomography scan. TC-MTX markedly decreased the secretion of inflammatory cytokines both in the serum and in inflamed joints of CIA mice. Further, its therapeutic potential is comparable to that of etanercept, a biological agent that block tumor necrosis factor (TNF)-α. Importantly, the systemic cytotoxicity of TC-MTX was not detected. Thus, TC-MTX can be a new therapeutic modality for RA patients without systemic complications.     

Investigation of the effect of different regulatory peptides on adrenocortical cell proliferation in immature rats: evidence that endogenous adrenomedullin exerts a stimulating action

Pseudoachondroplasia (PSACH) is an autosomal dominant disorder characterized by disproportionate short stature and precocious osteoarthritis. Radiographic manifestations include epiphyseal, metaphyseal and vertebral abnormalities. Mutations in the cartilage oligomeric matrix protein (COMP) have been identified to cause PSACH. Most of them affect one of the eight calcium-binding domains of COMP. We describe a clinically and radiologically typical PSACH 4-year-old girl and her 31-year-old father. A novel mutation, 1345-1347CCC deletion in exon 13, of COMP was identified in both patients. The deletion would be expected to result in the loss of the conserved proline at codon 449 from the sixth calcium-binding domain. This result further supports that COMP is the only gene, discovered to date, responsible for PSACH across different populations and that the calcium-binding domains are important to the function of the normal COMP.     

Thymidine and somatomedin-like activity of fetal pig sera: effect of fetal decapitation

The effect of fetal decapitation on porcine serum thymidine and somatomedin activity was studied. Fetal decapitation, at 45 d of gestation, did not alter body weight when compared to controls at 110 d of gestation. Thymidine activity, measured as 3H-thymidine incorporation into rat L6 myoblasts in response to test sera, did not differ between decapitated (D) and control (C) fetal pig sera. Thymidine activity of fetal sera was low when compared to a postnatal normal pig serum pool (NPS) and approximately equal to that of a postnatal hypophysectomized pig serum pool (HPS). Somatomedin-like activity, measured as 35S-sulfate uptake into 110 d fetal costal cartilage, was similar in D and C sera and was low when compared to NPS. Postnatal cartilage, but not fetal cartilage, responded greater to NPS than to HPS when measuring somatomedin activity. This indicates that fetal cartilage may be sensitive to different factors than postnatal pig cartilage. Thymidine activity and somatomedin-like activity were also low in maternal sera when compared to NPS. The concentration of insulin-like growth factor-I (IGF-I) was lower in D sera when compared to C sera (0.26 +/- 0.03 vs 0.62 +/- 0.09 U/ml, respectively, p less than 0.05). It is postulated that locally produced growth factors, compared to circulating growth factors, may be more important determinants controlling the rapid growth rate of the fetus.     

A Novel Combination of Methotrexate and Epigallocatechin Attenuates the Overexpression of Pro-inflammatory Cartilage Cytokines and Modulates Antioxidant Status in Adjuvant Arthritic Rats

The present study was designed to evaluate the combinatory effect of methotrexate (MTX) and epigallocatechin (EGCG) on the progression of adjuvant-induced arthritis in rats. Adjuvant arthritis (AA) was induced by a single intradermal injection of Freund's complete adjuvant. AA rats were treated with methotrexate (0.3 mg/kg) thrice a week, EGCG (100 mg/kg) daily, and combination of MTX and EGCG thrice a week for a period of 28 days. Paw swelling changes and histopathological and radiographic analysis was assessed to evaluate the antiarthritic effect. Lipid peroxidation and antioxidant enzyme activities in joint tissue homogenate were performed to observe the modulation of antioxidant status along the expression of different pro-inflammatory cartilage cytokines like TNF-α and IL-6. MTX and EGCG combination potentiated both the antiarthritic (decrease of hind paw volume) and the antioxidant effect (SOD, GSH, and catalase) as well as suppression of lipid peroxidation. Combination therapy of MTX and EGCG significantly inhibited the development phase of arthritis, which is supported by histopathological, radiographical, and attenuation of overexpression of cartilage cytokines. EGCG act as potent antioxidant and immunomodulator, suggesting that combined administration of MTX along with EGCG suppressed the development phase of arthritic progression in rats.     

Effects of ER-34122, a novel dual 5-lipoxygenase/cyclooxygenase inhibitor, on indices of early articular lesion in MRL/MpJ-lpr/lpr mice

OBJECTIVE AND DESIGN: To investigate effects of ER-34122, a novel dual 5-lipoxygenase (LOX)/cyclooxygenase (COX) inhibitor, and indomethacin on progression of articular lesions in MRL/MpJ-lpr/lpr (MRL/1) mice. MATERIAL: 100 male MRL/l mice. TREATMENT: ER-34122 (1-100 mg/kg) and indomethacin (1 mg/kg) were orally administered once a day to MRL/l mice from 6 to 10 or 16 weeks old. METHODS: Articular lesions were analyzed histopathologically in the early (10 weeks old) or late (16 weeks old) stages of MRL/l mice arthritis. Serum levels of rheumatoid factor were measured by using enzyme-linked immunosorbent assay. RESULTS: Articular lesions in the late stage of MRL/l mice arthritis were characterized by cartilage degeneration and pannus formation which were severer than those in the early stage. Polymorphonuclear leukocyte (PMN) infiltration and subsynovial soft tissue edema were observed as characteristic lesions in the early stage. ER-34122 suppressed progression of PMN infiltration, subsynovial soft tissue edema and multiplication of synovial lining cells in the early stage of the arthritis, even though it had no significant effect on other indices of articular lesion, enlargement of lymph nodes and serum levels of rheumatoid factors. On indices of late articular lesion, ER-34122 had no significant beneficial effects. Neither in the early nor late stage, indomethacin, a COX inhibitor, had significant effect on the arthritis at the examined dose. CONCLUSIONS: These results disclosed that ER-34122, a dual LOX/COX inhibitor, has anti-inflammatory activity in the early stage of the spontaneous arthritis.     

Circulating interleukin 10 and interleukin-6 serum levels in rheumatoid arthritis patients treated with methotrexate or gold salts: Preliminary report

In order to evaluate the relationship between serum concentrations of interleukin-10 (IL-10), IL-6, and acute phase proteins in rheumatoid arthritis (RA) patients treated with methotrexate (MTX) or intramuscular gold (IMG) we determined IL-10, IL-6, C-reactive protein (CRP), alpha-1-acid glycoprotein (AGP) and alpha-1-antichymotrypsin (ACT) in the sera of 35 RA patients. IL-10 and IL-6 levels were evaluated using an enzyme-linked immunoassay (ELISA). AGP and ACT level were measured using rocket immunoelectrophoresis. IL-10 serum level was not increased in RA patients as compared to controls (58.7 ± 18.1 pg/ml vs. 57.2 ± 11.9 pg/ml). IL-6 level was significantly elevated (91.6 ± 46.9 pg/ml vs. 45 ± 19 pg/ml, p < 0.05). CRP was significantly increased as compared to healthy controls (35 ± 19 mg/l vs. 3 ± 2 mg/l, p < 0.05). Patients treated with MTX or IMG presented an increased level of IL-10 and decreased amounts of IL-6, as compared to those treated with NSAID only. However, only changes between patients treated with IMG and NSAID were found to be statistically significant. A good negative correlation between IL-10 and IL-6 serum level was found (r = –0.75, p < 0.05). A positive significant correlation between IL-6 serum level and CRP (r = 0.62, p < 0.05), AGP (r = 0.78, p < 0.05) and ACT (r = 0.45, p < 0.05) was established. On the other hand, a negative correlation between IL-10 and serum level of CRP (r = –0.76, p < 0.05), AGP (r = –0.64, p < 0.05) and ACT (r = –0.38, p < 0.05) was also observed. Moreover, these relationships were maintained when patients treated with MTX, IMG, or NSAID were analyzed independently. According to the data thus far obtained, it seems that IL-10 decreases IL-6 production, and thereby indirectly affects the acute phase response, decreasing CRP, AGP, and ACT concentration in RA patients.Abbreviations ACT -1-antichymotrypsin - AGP ₁-acid glycoprotein - APP acute phase protein - CRP C-reactive protein - CSF colony stimulating factor - IFN interferon - IL interleukin - IMG intramuscular gold - MTX methotrexate - NSAID non-steroidal anti-inflammatory drug - RA rheumatoid arthritis