Oxidative Stress Biomarkers and Peripheral Endothelial Dysfunction in Rheumatoid Arthritis: A Monocentric Cross-Sectional Case-Control Study

Previous studies have suggested that oxidative stress may heighten atherosclerotic burden in rheumatoid arthritis (RA), but direct evidence is lacking. Objective: To evaluate the relationship between established plasma oxidative stress biomarkers and peripheral endothelial dysfunction (ED), a marker of early atherosclerosis, in RA. Methods: Paroxonase-1 (PON-1), protein-SH (PSH), and malondialdehyde (MDA) were measured in 164 RA patient s and 100 age- and sex-matched healthy controls without previous cardiovascular events. Peripheral ED, evaluated by flow-mediated pulse amplitude tonometry, was defined by log-transformed reactive hyperemia index (Ln-RHI) values < 0.51. Results: PON-1 activity and PSH concentrations were significantly reduced in RA patients compared to controls. In regression analysis, increased plasma MDA levels were significantly associated with reduced Ln-RHI [B coefficient (95% CI) = −0.003 (−0.005 to −0.0008), p = 0.008] and the presence of peripheral ED (OR (95% CI) = 1.75 (1.06–2.88), p = 0.028). Contrary to our expectations, increased PON-1 activity was significantly associated, albeit weakly, with the presence of ED (OR (95% CI) = 1.00 (1.00–1.01), p = 0.017). Conclusions: In this first evidence of a link between oxidative stress and markers of atherosclerosis, MDA and PON-1 showed opposite associations with peripheral vasodilatory capacity and the presence of ED in RA. Further studies are needed to determine whether this association predicts atherosclerotic events in the RA population

Comprehensive arginine metabolomics and peripheral vasodilatory capacity in rheumatoid arthritis: A monocentric cross-sectional study

Background: The relationship between plasma arginine metabolites influencing vascular homeostasis and peripheral vasodilatory capacity in rheumatoid arthritis (RA) patients is not known. Methods: L-arginine (Arg), monomethyl-L-arginine (MMA), L-homoarginine (hArg), asymmetric dimethyl-L-arginine (ADMA), symmetric dimethyl-L-arginine, and L-citrulline (Cit) were measured by liquid chromatography tandem mass spectrometry (LC-MS/MS) in 164 RA patients and 100 age- and sex-matched healthy controls without previous cardiovascular events. Log-transformed reactive hyperemia index (Ln-RHI) evaluated by flow-mediated pulse amplitude tonometry (PAT, EndoPAT2000 device) was assessed as surrogate measure of peripheral vasodilatory capacity in RA patients. Ln-RHI values <0.51 indicated peripheral endothelial dysfunction (ED). The relationship between plasma arginine metabolite concentrations, RA descriptors and peripheral vasodilatory capacity was evaluated by bivariate correlation and regression analyses. Results: Plasma ADMA concentrations were significantly higher, and plasma hArg concentrations significantly lower, in RA patients than in controls (0.53 ± 0.09 vs 0.465 ± 0.07 μmol/L and 1.50 ± 0.60 vs 1.924 ± 0.78 μmol/L, respectively; p < 0.001 for both comparisons). Bivariate correlation analysis demonstrated no significant correlation between arginine metabolites and disease descriptors. In regression analysis in RA patients, higher plasma ADMA concentrations were independently associated with presence of ED [OR(95% CI) = 77.3(1.478–4050.005), p = 0.031] and lower Ln-RHI [B coefficient(95% CI) = −0.57(−1.09 to −0.05), p = 0.032]. Conclusions: ADMA was significantly, albeit weakly, associated with impaired microcirculatory vasodilatory capacity and peripheral endothelial dysfunction in RA. This suggests an important pathophysiological role of this metabolite in the vascular alterations observed in this patient group

Methotrexate and vasculoprotection: Mechanistic insights and potential therapeutic applications in old age

Increasing age is a strong, independent risk factor for atherosclerosis and cardiovascular disease. Key abnormalities driving cardiovascular risk in old age include endothelial dysfunction, increased arterial stiffness, blood pressure, and the pro-atherosclerotic effects of chronic, low-grade, inflammation. The identification of novel therapies that comprehensively target these alterations might lead to a major breakthrough in cardiovascular risk management in the older population. Systematic reviews and meta-analyses of observational studies have shown that methotrexate, a first-line synthetic disease-modifying anti-rheumatic drug, significantly reduces cardiovascular morbidity and mortality in patients with rheumatoid arthritis, a human model of systemic inflammation, premature atherosclerosis, and vascular aging. We reviewed in vitro and in vivo studies investigating the effects of methotrexate on endothelial function, arterial stiffness, and blood pressure, and the potential mechanisms of action involved. The available evidence suggests that methotrexate might have beneficial effects on vascular homeostasis and blood pressure control by targeting specific inflammatory pathways, adenosine metabolism, and 5' adenosine monophosphate-activated protein kinase. Such effects might be biologically and clinically relevant not only in patients with rheumatoid arthritis but also in older adults with high cardiovascular risk. Therefore, methotrexate has the potential to be repurposed for cardiovascular risk management in old age because of its putative pharmacological effects on inflammation, vascular homeostasis, and blood pressure. However, further study and confirmation of these effects are essential in order to adequately design intervention studies of methotrexate in the older population

Clinical Features of Diabetes Mellitus on Rheumatoid Arthritis: Data from the Cardiovascular Obesity and Rheumatic DISease (CORDIS) Study Group

Rheumatoid arthritis (RA) and diabetes mellitus (DM) are linked by underlying inflammation influencing their development and progression. Nevertheless, the profile of diabetic RA patients and the impact of DM on RA need to be elucidated. This cross-sectional study includes 1523 patients with RA and no episodes of cardiovascular events, followed up in 10 Italian University Rheumatologic Centers between 1 January and 31 December 2019 belonging to the “Cardiovascular Obesity and Rheumatic DISease (CORDIS)” Study Group of the Italian Society of Rheumatology. The demographic and clinical features of DM RA patients were compared to non-diabetic ones evaluating factors associated with increased risk of DM. Overall, 9.3% of the RA patients had DM, and DM type 2 was more common (90.2%). DM patients were significantly older (p < 0.001), more frequently male (p = 0.017), with a significantly higher BMI and mean weight (p < 0.001) compared to non-diabetic patients. DM patients were less likely to be on glucocorticoids (p < 0.001), with a trend towards a more frequent use of b/ts DMARDs (p = 0.08), and demonstrated higher HAQ (p = 0.001). In around 42% of patients (n = 114), DM diagnosis preceded that of RA. Treatment lines were identical in diabetic and non-diabetic RA patients. DM is a comorbidity that may influence RA management and outcome. The association between DM and RA supports the theory of systemic inflammation as a condition underlying the development of both diseases. DM may not have a substantial impact on bDMARDs resistance, although further investigation is required to clarify the implications of biological therapy resistance in RA patients

Current smoking predicts inadequate response to methotrexate monotherapy in rheumatoid arthritis patients naïve to DMARDs: Results from a retrospective cohort study

Identifying predictors of inadequate response to methotrexate (MTX) in rheumatoid arthritis (RA) is key to move from a "trial and error" to a "personalized medicine" treatment approach where patients less likely to adequately respond to MTX monotherapy could start combination therapy at an earlier stage. This study aimed to identify potential predictors of inadequate response to MTX in RA patients naïve to disease modifying anti-rheumatic drugs.Data from a real-life cohort of newly diagnosed RA patients starting MTX (baseline, T0) as first-line therapy were analyzed. Outcomes, assessed after 6 months (T1), were defined as failure to achieve a disease activity score 28 (DAS28) low disease activity (LDA) or a good/moderate response to MTX, according to the European League Against Rheumatism (EULAR) response criteria. Logistic regression was used to assess the associations between baseline variables and the study outcomes.Overall, 294 patients (60.5% females, median age 54.5 years) with a median disease duration of 7.9 months were recruited. At T1, 47.3% of subjects failed to achieve LDA, and 29.3% did not have any EULAR-response. In multivariate analysis, significant associations were observed between no LDA and current smoking (adjusted odds ratio [adjOR] 1.79, P = .037), female gender (adjOR 1.68, P = .048), and higher DAS28 (adjOR 1.31, P = .013); and between no EULAR-response and current smoking (adjOR: 2.04, P = .019), age (adjOR: 0.72 per 10-years increases, P = .001), and higher erythrocyte sedimentation rate (adjOR: 0.49; P = .020). By contrast, there were no associations between past smoker status and study outcomes.In summary, in our real-life cohort of disease modifying anti-rheumatic drug naïve RA patients, current smoking habit independently predicts inadequate response to MTX. This, together with other independent predictors of response to treatment identified in our study, might assist with personalized monitoring in RA patients. Further studies are required to investigate whether smoking quitting strategies enhance the therapeutic response to MTX

Role of cellular senescence and NOX4-mediated oxidative stress in systemic sclerosis pathogenesis.

Systemic sclerosis (SSc) is a systemic autoimmune disease characterized by progressive fibrosis of skin and numerous internal organs and a severe fibroproliferative vasculopathy resulting frequently in severe disability and high mortality. Although the etiology of SSc is unknown and the detailed mechanisms responsible for the fibrotic process have not been fully elucidated, one important observation from a large US population study was the demonstration of a late onset of SSc with a peak incidence between 45 and 54 years of age in African-American females and between 65 and 74 years of age in white females. Although it is not appropriate to consider SSc as a disease of aging, the possibility that senescence changes in the cellular elements involved in its pathogenesis may play a role has not been thoroughly examined. The process of cellular senescence is extremely complex, and the mechanisms, molecular events, and signaling pathways involved have not been fully elucidated; however, there is strong evidence to support the concept that oxidative stress caused by the excessive generation of reactive oxygen species may be one important mechanism involved. On the other hand, numerous studies have implicated oxidative stress in SSc pathogenesis, thus, suggesting a plausible mechanism in which excessive oxidative stress induces cellular senescence and that the molecular events associated with this complex process play an important role in the fibrotic and fibroproliferative vasculopathy characteristic of SSc. Here, recent studies examining the role of cellular senescence and of oxidative stress in SSc pathogenesis will be reviewed

Clinical spectrum time course in non-Asian patients positive for anti-MDA5 antibodies

Objectives: To define the clinical spectrum time-course and prognosis of non-Asian patients positive for anti-MDA5 antibodies. Methods: We conducted a multicentre, international, retrospective cohort study. Results: 149 anti-MDA5 positive patients (median onset age 53 years, median disease duration 18 months), mainly females (100, 67%), were included. Dermatomyositis (64, 43%) and amyopathic dermatomyositis (47, 31%), were the main diagnosis; 15 patients (10%) were classified as interstitial pneumonia with autoimmune features (IPAF) and 7 (5%) as rheumatoid arthritis. The main clinical findings observed were myositis (84, 56%), interstitial lung disease (ILD) (108, 78%), skin lesions (111, 74%), and arthritis (76, 51%). The onset of these manifestations was not concomitant in 74 cases (50%). Of note, 32 (21.5%) patients were admitted to the intensive care unit for rapidly progressive-ILD, which occurred in median 2 months from lung involvement detection, in the majority of cases (28, 19%) despite previous immunosuppressive treatment. One-third of patients (47, 32% each) was ANA and anti-ENA antibodies negative and a similar percentage was anti-Ro52 kDa antibodies positive. Non-specific interstitial pneumonia (65, 60%), organising pneumonia (23, 21%), and usual interstitial pneumonia-like pattern (14, 13%) were the main ILD patterns observed. Twenty-six patients died (17%), 19 (13%) had a rapidly progressive-ILD. Conclusions: The clinical spectrum of the anti-MDA5 antibodies-related disease is heterogeneous. Rapidly-progressive ILD deeply impacts the prognosis also in non-Asian patients, occurring early during the disease course. Anti-MDA5 antibody positivity should be considered even when baseline autoimmune screening is negative, anti-Ro52 kDa antibodies are positive, and radiology findings show a NSIP pattern

Interaction of metal ions with humic-like models. Part. I. Synthesis, spectroscopic and structural properties of diaquabis(2,6-dihydroxybenzoato) copper(II) and hexaaquaM(II) bis(2,6-dihydroxybenzoate) dihydrate (M = Mn, Fe, Co, Ni, Cu and Zn)

Compounds of the type M(2,6-DHB)2\ub78H2O (M = Mn, Fe, Co, Ni, and Zn; 2,6-DHB = 2,6-dihydroxybenzoate ion) and Cu(2,6-DHB)2(H2O)2 were prepared and characterized by means of infrared and electronic spectroscopy, electron spin resonance and thermal analysis. For Cu(2,6-DHB)2(H2O)2 (1) and Zn(2,6-DHB)2\ub78H2O (2) the crystal structure was also determined by single-crystal X-ray diffraction methods. The compound (1) has a polymeric nature, the coordination around each copper atom being tetragonally-distorted octahedral, with two water oxygens [CuO, 1.966(3) \uc5] and two carboxyl oxygens [CuO, 1.935(2) \uc5] from 2,6-DHB molecules about the square plane and two phenolic groups from adjacent units in the axial positions. The structure of (2) consists of almost regular octahedral [Zn(H2O)6]2+ cations surrounded by 2,6-DHB anions. The remaining two water molecules are involved in hydrogen bonding with the coordinated water molecules. X-ray data show that all the M(2,6-DHB)2\ub78H2O are isomorphous with (2). The thermal, spectroscopic and magnetic properties are interpreted on the basis of the crystal structures. In particular, the ESR and absorption data of the copper(II) compounds are compared with those of the salicylate complexes. \ua9 1983

Interaction of metal ions with humic-like models. Part VII. Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes of 2,5-dihydroxybenzoic acid

Complexes of formula M(2,5-DHB)24H2O (M = Mn, Co, Ni, Zn, Cu and Cd; 2,5-DHB = 2,5-dihydroxybenzoate) were prepared and characterized by means of infrared and electronic spectroscopy, and by electron spin resonance. For the Zn complex the crystal and molecular structure was also determined by single-crystal X-ray diffraction analysis. The crystal is orthorhombic, space group Pbca (No. 61), with a = 18.503(4), b = 13.536(3), c = 6.900(2) \uc5, and Z = 4. The final refinement used 877 reflections and gave a residual R value of 0.041. The complex has slightly compressed octahedral coordination, with the zinc atom bound to two monodentate carboxylate groups lying in trans positions and four water molecules. X-ray data and infrared spectra show the Mn, Co, Ni, Zn and Cd complexes to be isostructural with the Zn compound. The electronic, infrared and ESR spectra of the copper(II) complex are consistent with a CuO4- based chromophore involving two water molecules and two monodentate carboxylate groups in the metal plane, and long axial contacts. \ua9 1985