Interleukin 17 as a novel predictor of vascular function in rheumatoid arthritis

Exploration of Risk Factors for Cardiovascular Disease in Patients with Rheumatoid Arthritis: A Retrospective Study

OBJECTIVE

Patients with rheumatoid arthritis (RA) have increased mortality and morbidity rates owing to cardiovascular diseases (CVD). Timely detection of CVD in RA can greatly improve patient prognosis; however, this technique remains challenging. We aimed to investigate the risk factors for CVD incidence in patients with RA.

METHODS

This retrospective study included RA patients without CVD risk factors (n = 402), RA with CVD risk factors (n = 394), and RA with CVD (n = 201). Their data on routine examination indicators, vascular endothelial growth factor (VEGF), and immune cells were obtained from medical records. The characteristic variables between each group were screened using univariate analysis, least absolute shrinkage and selection operator (LASSO), random forest (RF), and logistic regression (LR) models, and individualized nomograms were further established to more conveniently observe the likelihood of CVD in RA.

RESULTS

Univariate analysis revealed significantly elevated levels of white blood cells (WBC), blood urea nitrogen (BUN), creatinine, creatine kinase (CK), lactate dehydrogenase (LDH), VEGF, serum total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), apolipoprotein B100 (ApoB100), and apolipoprotein E (ApoE) in RA patients with CVD, whereas apolipoprotein A1 (ApoA1) and high-density lipoprotein/cholesterol (HDL/TC) were decreased. Furthermore, the ratio of regulatory T (Treg) cells exhibiting excellent separation performance in RA patients with CVD was significantly lower than that in other groups, whereas the ratios of Th1/Th2/NK and Treg cells were significantly elevated. The LASSO, RF, and LR models were also used to identify the risk factors for CVD in patients with RA. Through the final selected indicators screened using the three machine learning models and univariate analysis, a convenient nomogram was established to observe the likelihood of CVD in patients with RA.

CONCLUSIONS

Serum lipids, lipoproteins, and reduction of Treg cells have been identified as risk factors for CVD in patients with RA. Three nomograms combining various risk factors were constructed to predict CVD occurring in patients with RA (RA with/without CVD risk factors).

Role of endothelial dysfunction in sleep-disordered breathing in egyptian children with sickle cell disease

BACKGROUND

Endothelial dysfunction is an integral pathophysiologic mechanism in sickle cell disease (SCD), and can lead to many complications. Sleep-disordered breathing (SDB) is a SCD complication with diverse incidence and pathophysiology. This study aimed to determine the prevalence of SDB in children with SCD and to assess its relation to endothelial dysfunction.

METHODS

Sixty children with SCD and 60 healthy controls were enrolled. The levels of TNF-α, IL-6, and IL-17A were evaluated in the entire cohort using enzyme-linked immunosorbent assay (ELISA) kits. Polysomnography (PSG) was performed for all SCD patients after completion of the Pediatric Sleep Questionnaire (PSQ).

RESULTS

TNF-α, IL-6, and IL-17A levels were significantly greater in children with SCD than in controls (p-values < 0.001, < 0.001, and 0.006, respectively). The PSQ revealed symptoms suggestive of SDB in 50 children with SCD (83.3%), and PSG revealed obstructive sleep apnea (OSA) in 44 children with SCD (73.3%); 22 patients had mild OSA, and 22 had moderate-to-severe OSA according to the apnea-hypopnea index (AHI). TNF-α was significantly greater in SCD children who reported heavy or loud breathing, trouble breathing or struggle to breathe, and difficulty waking up in the morning (p-values = 0.002, 0.002, and 0.031, respectively). The IL-6 levels were significantly greater in SCD children who stopped growing normally (p-value = 0.002). The levels of IL-6 and IL-17A were significantly greater in SCD children with morning headaches (p-values = 0.007 and 0.004, respectively).

CONCLUSION

Children with SCD showed a high prevalence of SDB with significantly elevated levels of markers of endothelial function, highlighting the interplay of SDB and endothelial dysfunction in SCD.

Circulating Interleukin 17A and Other Inflammatory Proteins May Predict Cardiovascular Disease in Early Rheumatoid Arthritis

OBJECTIVE

The objective of this study was to investigate the impact of 92 inflammatory proteins on the risk of cardiovascular disease (CVD) in patients with early rheumatoid arthritis (RA).

METHODS

This study included consecutive patients with early RA recruited between 1995 and 2002. Stored plasma samples were analyzed for 92 inflammatory proteins. CVD diagnoses were retrieved from national in-patient and cause-of-death registries. Statistical analyses were predesignated as hypothesis-driven or exploratory. For the latter, proteins were selected based on principal component analysis (ie, factor loading > 0.5 within main components). Potential predictors of CVD and coronary artery disease (CAD) were assessed using Cox regression.

RESULTS

Data on baseline levels of proteins and CVD were available for 163 patients. As hypothesized, levels of interleukin 17A (IL-17A) were associated with CVD (hazard ratio 1.35, 95% CI 1.02-1.78, adjusted for age, sex, hypertension, diabetes, smoking, and erythrocyte sedimentation rate [ESR]), although not significantly with CAD. Osteoprotegerin (OPG) levels were significantly associated with both outcomes, but only in crude models. No associations were observed for IL-6, tumor necrosis factor, monocyte chemotactic protein-1, or IL-8. In the exploratory analyses, MCP-3 in particular had significant associations with both outcomes in crude models.

CONCLUSION

Circulating IL-17A at RA diagnosis predicted future CVD, although we cannot exclude the possibility that this finding is due to multiple testing. The association was independent of traditional CVD risk factors, and of ESR at the time of diagnosis. Further, OPG may be a predictor of CVD. We also identified some novel potential biomarkers for CVD in RA.

A Review of MicroRNAs and lncRNAs in Atherosclerosis as Well as Some Major Inflammatory Conditions Affecting Atherosclerosis

It is generally accepted that atherosclerosis is a chronic inflammatory disease. The link between atherosclerosis and other inflammatory diseases such as psoriasis, type 2 diabetes mellitus (T2DM), and rheumatoid arthritis (RA) via metabolic, inflammatory, and immunoregulatory pathways is well established. The aim of our review was to summarize the associations between selected microRNAs (miRs) and long non-coding RNAs (lncRNAs) and atherosclerosis, psoriasis, T2DM, and RA. We reviewed the role of miR-146a, miR-210, miR-143, miR-223, miR-126, miR-21, miR-155, miR-145, miR-200, miR-133, miR-135, miR-221, miR-424, let-7, lncRNA-H19, lncRNA-MEG3, lncRNA-UCA1, and lncRNA-XIST in atherosclerosis and psoriasis, T2DM, and RA. Extracellular vesicles (EVs) are a method of intracellular signal transduction. Their function depends on surface expression, cargo, and the cell from which they originate. The majority of the studies that investigated lncRNAs and some miRs had relatively small sample sizes, which limits the generalizability of their findings and indicates the need for more research. Based on the studies reviewed, miR-146a, miR-155, miR-145, miR-200, miR-133, and lncRNA-H19 are the most promising potential biomarkers and, possibly, therapeutic targets for atherosclerosis as well as T2DM, RA, and psoriasis.

Si-Miao-Yong-An Decoction alleviates thromboangiitis obliterans by regulating miR-548j-5p/IL-17A signaling pathway

Thromboangiitis obliterans (TAO) is a rare, chronic, progressive, and segmental inflammatory disease characterized by a high rate of amputation, significantly compromising the quality of life of patients. Si-Miao-Yong-An decoction (SMYA), a traditional prescription, exhibits anti-inflammatory, anti-thrombotic, and various other pharmacological properties. Clinically, it was fully proved to be effective for TAO therapy, but the specific therapeutic effect of SMYA on TAO has been unknown. Thus, deep unveiling the mechanism of SMYA in TAO for identifying clinical therapeutic targets is extremely important. In this study, we observed elevated levels of IL-17A in the peripheral blood mononuclear cells (PBMCs) of TAO patients, whereas the expression of miR-548j-5p was significantly decreased. A negative correlation between the levels of miR-548j-5p and IL-17A was also demonstrated. In vitro experiments showed that overexpression of miR-548j-5p led to a decrease in IL-17A levels, whereas downregulation of miR-548j-5p showed the opposite effect. Using a dual luciferase assay, we confirmed that miR-548j-5p directly targets IL-17A. Furthermore, serum containing SMYA effectively decreased IL-17A levels by increasing the expression of miR-548j-5p. More importantly, the results of in vivo tests indicated that SMYA mitigated the development of TAO by inhibiting IL-17A through the upregulation of miR-548j-5p in vascular tissues. In conclusion, SMYA significantly enhances the expression of miR-548j-5p, thereby reducing the levels of the target gene IL-17A and alleviating TAO. Our research not only identifies novel targets and pathways for the clinical diagnosis and treatment of TAO but also advances the innovation in traditional Chinese medicine through the elucidation of the SMYA/miR-548j-5p/IL-17A regulatory axis in the pathogenesis of TAO.

Aberrant cytokine and VCAM-1 expression in patients with viral and non-viral related liver cirrhosis

The study aim was to compare the alterations in the expression levels of proinflammatory and chemotactic cytokines as tumor necrosis factor-alpha (TNF-α), interleukin (IL)-17A and IL-8, the down regulatory cytokine IL-10, in addition to the vascular cell adhesion molecule-1 (VCAM-1) gene in different groups of patients with cirrhosis due to various etiologies. This case-control study included 84 patients suffering from cirrhosis of viral and non-viral etiologies and 20 sex and age-matched healthy controls. All patients were subjected to detailed history taking, clinical examination, and liver function assessment. The expression levels of TNF-α, IL-17A, IL-8, IL-10, and VCAM-1 were assessed in peripheral blood mononuclear cells by real-time PCR. Patients with cirrhosis showed marked changes in the tested gene expression levels relative to the control group. Higher expression levels of all genes except IL-10 were seen in patients of the viral than in the non-viral groups. Most of the significant correlations of liver function parameters were observed with TNF-α in both the viral and non-viral groups, followed by IL-17A. Increased TNF-α and IL-17A presented potential risk factors for disease progression to cirrhosis of Child class C.

Global research trends and focus on the link between rheumatoid arthritis and neutrophil extracellular traps: a bibliometric analysis from 1985 to 2023

Rheumatoid arthritis (RA) is an autoimmune disease that currently has an unknown cause and pathogenesis, and is associated with many complications and a high disability rate. The neutrophil extracellular trap network (NETs) is a newly discovered mechanism that allows neutrophils to capture and kill pathogens. Multiple studies in recent years have highlighted its relevance to the progression of rheumatoid arthritis. Despite the growing number of studies indicating the crucial role of NETs in RA, there has been no bibliometric review of research hotspots and trends in this area. In this study, we retrieved articles related to NETs in RA from the Web of Science Core Collection (WoSCC) database from 1985 to 2023 and used visualization tools such as Citespace, VOSviewer, Tableau Public, and Microsoft Office Excel 2021 to analyze the data. After screening, we included a total of 416 publications involving 2,334 researchers from 1,357 institutions in 167 countries/regions, with relevant articles published in 219 journals. The U.S., China, and Germany are the top 3 countries/regions with 124, 57, and 37 publications respectively. Mariana J. Kaplan is the most published author, and journals such as Frontiers in Immunology and International Journal of Molecular Sciences have had a significant impact on research in this field. The clinical application of PAD enzymes and their inhibitors, and the drug development of NETs as therapeutic targets for RA is a trend for future research. Our study provides a comprehensive bibliometric analysis and summary of NETs in RA publications, which will aid researchers in conducting further scientific research.

Dietary regulation of peroxisome proliferator-activated receptors in metabolic syndrome

BACKGROUND

Peroxisome proliferator-activated receptors (PPARs) are a class of ligand-activated nuclear transcription factors, members of the type nuclear receptor superfamily, with three subtypes, namely PPARα, PPARβ/δ, and PPARγ, which play a key role in the metabolic syndrome. In the past decades, a large number of studies have shown that natural products can act by regulating metabolic pathways mediated by PPARs.

PURPOSE

This work summarizes the physiological importance and clinical significance of PPARs and reviews the experimental evidence that natural products mediate metabolic syndrome via PPARs.

METHODS

This study reviews relevant literature on clinical trials, epidemiology, animals, and cell cultures published in NCBI PubMed, Scopus, Web of Science, Google Scholar, and other databases from 2001 to October 2022. Search keywords were "natural product" OR "botanical" OR "phytochemical" AND "PPAR" as well as free text words.

RESULTS

The modulatory involvement of PPARs in the metabolic syndrome has been supported by prior research. It has been observed that many natural products can treat metabolic syndrome by altering PPARs. The majority of currently described natural compounds are mild PPAR-selective agonists with therapeutic effects that are equivalent to synthetic medicines but less harmful adverse effects.

CONCLUSION

PPAR agonists can be combined with natural products to treat and prevent metabolic syndrome. Further human investigations are required because it is unknown how natural products cause harm and how they might have negative impacts.

Relevance of circulating markers of endothelial activation for cardiovascular risk assessment in rheumatoid arthritis: a narrative review

Rheumatoid arthritis (RA) is associated with excessive cardiovascular mortality secondary to premature atherosclerosis, in which endothelial activation (EA) plays a central role. EA is characterized by loss of vascular integrity, expression of leucocyte adhesion molecules, transition from antithrombotic to prothrombotic phenotype, cytokines production, shedding of membrane microparticles and recruitment of endothelial progenitor cells. As EA is an early event in atherogenesis, circulating markers of EA are putative markers of vascular pathology and cardiovascular (CV) risk. After a presentation of biology of EA, the present review analyzed the available data regarding changes in EA markers in RA in link with the vascular pathology and CV events, discussed their relevance as biomarkers of CV risk and proposed future directions.

Accelerated atherosclerosis in rheumatoid arthritis: a systematic review

Background: Rheumatoid arthritis (RA) is a highly prevalent, chronic inflammatory condition of the synovial joints that affects approximately 1% of the global population. The pathogenesis of RA is predominantly inflammatory in nature, thereby accelerating the co-occurrence of other immunoinflammatory conditions such as atherosclerosis. Apart from traditional cardiovascular risk factors, RA patients possess a multitude of other factors that predispose them to early atherosclerotic disease. The aim of this systematic review is to assess the prevalence of premature atherosclerosis in RA patients and elucidate the role that proinflammatory cytokines, RA-related autoantibodies, and endothelial dysfunction play in the pathophysiology of RA-mediated atherosclerosis. We also discussed novel biomarkers that can be used to predict early atherosclerosis in RA and current guidelines used to treat RA. Methods: This review followed the PRISMA guidelines to select and analyze relevant articles. A literature search for articles was performed on February 25, 2022, through three research databases including PubMed, ProQuest, and ScienceDirect. The query used to identify relevant publications was "Rheumatoid arthritis and atherosclerosis" and the search duration was set from 2012-2022. Relevant articles were selected based on the inclusion and exclusion criteria. Results: Our initial search generated 21,235 articles. We narrowed our search according to the inclusion and exclusion criteria. After assessing eligibility based on the full content of the articles, 73 articles were ultimately chosen for this review. Conclusion: There is an increased prevalence of accelerated atherosclerosis among RA patients. We found evidence to explain the role of proinflammatory cytokines, RA-related autoantibodies, and endothelial dysfunction in the pathophysiology RA-mediated atherosclerosis. Therapies targeting either the inflammatory load or traditional CV risk-factors seem to improve vascular outcomes in RA patients. Novel markers of atherosclerosis in RA may be useful in predicting premature atherosclerosis and serve as new targets for therapeutic intervention.

Necroptosis Plays a Crucial Role in Vascular Injury during DVT and Is Enhanced by IL-17B

Background. This study investigated whether vascular endothelial necroptosis is involved in deep vein thrombosis (DVT) and how IL-17B facilitates necroptosis signaling. Methods. The DVT mouse model was induced by ligation of the IVC. The cross-sectional area of thrombus increases and the thrombus occupied the entire venous lumen at 48 h after ligation. Meanwhile, the increased expression of p-RIP3/RIP3 was most pronounced at 48 h after ligation, and the p-MLKL/MLKL peaked at 72 h. Results. Based on Illumina sequencing and KEGG pathway analyses, the activated RIP3/MLKL is associated with increased IL-17B. With thrombus formation, IL-17B was upregulated and enhanced the expression of RIP3 and MLKL in the IVC wall, as well as their phosphorylation levels (all $P<0.05$ , the comparison group consisted of the control group, DVT group, DVT/IL-17B group, and DVT/anti-IL-17B group). The p-RIP3/RIP3 and p-MLKL/MLKL ratios were reduced by anti-IL-17B. Similarly, the weight and cross-sectional area of the thrombi were increased by IL-17B and decreased by the IL-17B antibody. IL-17B had a smaller effect on thrombosis in knockout mice compared with WT mice. In vitro, the IL-17B protein expression and the level of RIP3 and MLKL phosphorylation increased high in the OGD cells, accompanied by increased expression of IL-6 and TNF-α. IL-17B enhanced the expression of IL-6 and TNF-α but had little effect on the IL-6 and TNF-α after transfected with siRIP3 or siMLKL. Similarly, the plasma IL-17B, IL-6, and TNF-α were significantly increased after thrombosis in WT mice, and enhanced by IL-17B. But IL-17B did not increase the plasma IL-6 and TNF-α in knockout mice. Conclusions. In conclusion, those results suggest that vascular endothelial necroptosis plays a crucial role in vascular injury and IL-17B could enhance the necroptosis pathway.

Effects of local cryotherapy on systemic endothelial activation, dysfunction, and vascular inflammation in adjuvant-induced arthritis (AIA) rats

Aim

This study explored the systemic vascular effects of local cryotherapy with a focus on endothelial changes and arterial inflammation in the model of rat adjuvant-induced arthritis (AIA).

Methods

Cryotherapy was applied twice a day on hind paws of AIA rats from the onset of arthritis to the acute inflammatory phase. Endothelial activation was studied in the aorta by measuring the mRNA levels of chemokines (CXCL-1, MCP-1 (CCL-2), MIP-1α (CCL-3)) and adhesion molecules (ICAM-1, VCAM-1) by qRT-PCR. Endothelial dysfunction was measured in isolated aortic and mesenteric rings. Aortic inflammation was evaluated via the mRNA expression of pro-inflammatory cytokines (TNF-α, IL-6) by qRT-PCR and leucocyte infiltration analysis (flow cytometry). Plasma levels of TNF-α, IL-6, IL-1β, IL-17A, and osteoprotegerin (OPG) were measured using Multiplex/ELISA.

Results

AIA was associated with an increased aortic expression of CXCL-1 and ICAM-1 as well as an infiltration of leucocytes and increased mRNA expression of IL-6, IL-1β, and TNF-α. Local cryotherapy, which decreased arthritis score and structural damages, reduced aortic mRNA expression of CXCL-1, IL-6, IL-1β, and TNF-α, as well as aortic infiltration of leucocytes (T lymphocytes, monocytes/macrophages, neutrophils) and improved acetylcholine-induced vasorelaxation in the aorta and mesenteric arteries. Plasma levels of IL-17A and OPG were significantly reduced by cryotherapy, while the number of circulating leucocytes was not. IL-17A levels positively correlated with endothelial activation and dysfunction.

Conclusion

In the AIA model, local cryotherapy reduced systemic endothelial activation, immune cell infiltration, and endothelial dysfunction. Mechanistically, the reduction of circulating levels of IL-17A appears as the possible link between joint cooling and the remote vascular effects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02774-1.

Accelerated atherosclerosis in rheumatoid arthritis: a systematic review

Background: Rheumatoid arthritis (RA) is a highly prevalent, chronic inflammatory condition of the synovial joints that affects approximately 1% of the global population. The pathogenesis of RA is predominantly inflammatory in nature, thereby accelerating the co-occurrence of other immunoinflammatory conditions such as atherosclerosis. Apart from traditional cardiovascular risk factors, RA patients possess a multitude of other factors that predispose them to early atherosclerotic disease. The aim of this systematic review is to assess the prevalence of premature atherosclerosis in RA patients and elucidate the role that proinflammatory cytokines, RA-related autoantibodies, and endothelial dysfunction play in the pathophysiology of RA-mediated atherosclerosis. We also discussed novel biomarkers that can be used to predict early atherosclerosis in RA and current guidelines used to treat RA. Methods: This review followed the PRISMA guidelines to select and analyze relevant articles. A literature search for articles was performed on February 25, 2022, through three research databases including PubMed, ProQuest, and ScienceDirect. The query used to identify relevant publications was "Rheumatoid arthritis and atherosclerosis" and the search duration was set from 2012-2022. Relevant articles were selected based on the inclusion and exclusion criteria. Results: Our initial search generated 21,235 articles. We narrowed our search according to the inclusion and exclusion criteria. After assessing eligibility based on the full content of the articles, 73 articles were ultimately chosen for this review. Conclusion: There is an increased prevalence of accelerated atherosclerosis among RA patients. We found evidence to explain the role of proinflammatory cytokines, RA-related autoantibodies, and endothelial dysfunction in the pathophysiology RA-mediated atherosclerosis. Therapies targeting either the inflammatory load or traditional CV risk-factors seem to improve vascular outcomes in RA patients. Novel markers of atherosclerosis in RA may be useful in predicting premature atherosclerosis and serve as new targets for therapeutic intervention.

Serum catestatin levels in patients with rheumatoid arthritis

Catestatin (CST) is an important peptide that influences various inflammatory diseases. Our goal was to investigate CST concentrations in patients with RA compared to healthy subjects. This cross-sectional observational study included 80 patients with RA and 80 healthy control subjects. Demographic characteristics and laboratory parameters were recorded. Serum CST levels were determined by an enzyme-linked immunosorbent assay (ELISA). Serum CST levels were significantly higher in RA patients than in the control group (10.53 ± 3.90 vs 5.24 ± 2.37 ng/mL, p < 0.001). In RA patients, there was a statistically significant correlation between CST and patient age (r = 0.418, p < 0.001) and both DAS28 (r = 0.469, p < 0.001) and HAQ scores (r = 0.483, p < 0.001). There was a statistically significant correlation between serum CST levels and RA duration (r = 0.583, p < 0.001). Multiple linear regression analysis showed that serum CST levels retained a significant association with RA duration (β ± SE, 0.13 ± 0.04, p = 0.002) and DAS28 score (0.94 ± 0.45, p = 0.039) after model adjustment for age, body mass index (BMI) and HAQ score, with serum CST levels as a dependent variable. These findings imply that CST is possibly associated with RA complex pathophysiology and disease activity. However, future larger multicentric longitudinal studies are necessary to define the role of CST in RA.

Ischemic Heart Disease and Rheumatoid Arthritis-Two Conditions, the Same Background

Rheumatoid arthritis (RA) is one of the most frequent inflammatory rheumatic diseases, having a considerably increased prevalence of mortality and morbidity due to cardiovascular disease (CVD). RA patients have an augmented risk for ischemic and non-ischemic heart disease. Increased cardiovascular (CV) risk is related to disease activity and chronic inflammation. Traditional risk factors and RA-related characteristics participate in vascular involvement, inducing subclinical changes in coronary microcirculation. RA is considered an independent risk factor for coronary artery disease (CAD). Endothelial dysfunction is a precocious marker of atherosclerosis (ATS). Pro-inflammatory cytokines (such as TNFα, IL-1, and IL-6) play an important role in synovial inflammation and ATS progression. Therefore, targeting inflammation is essential to controlling RA and preventing CVD. Present guidelines emphasize the importance of disease control, but studies show that RA- treatment has a different influence on CV risk. Based on the excessive risk for CV events in RA, permanent evaluation of CVD in these patients is critical. CVD risk calculators, designed for the general population, do not use RA-related predictive determinants; also, new scores that take into account RA-derived factors have restricted validity, with none of them encompassing imaging modalities or specific biomarkers involved in RA activity.

Triggers of Cardiovascular Diseases in Rheumatoid Arthritis

The risk of cardiovascular disease (CVD) in patients with rheumatoid arthritis (RA) is higher than that in patients without RA, and it is even higher than that in patients with diabetes. Autoimmune-mediated inflammation is observed in patients with RA, resulting in endothelial dysfunction, oxidative stress and activation, and vascular migration of white blood cells. Traditionally, RA-associated CVD was assumed to be mediated by disease-related inflammation, resulting in atherosclerosis (AS). However, this concept has been challenged because treatment with anti-rheumatic drugs, such as methotrexate or proinflammatory cytokine antagonists, such as tumor necrosis factor-alpha (TNF-α) inhibitors, did not reduce the risk of CVD in patients with RA. Current cardiovascular guidelines recommend screening and treatment of CVD risk factors in patients with RA but without clear biomarkers and treatment goals. There is no scientific basis for establishing therapeutic targets for cardiovascular risk factors in RA. Numerous studies have shown that the mechanism of early cardiac dysfunction in patients with RA may occur prior to AS. Therefore, it is crucial to explore the related mechanisms to prevent early cardiac dysfunction in patients with RA.

Systemic microvascular endothelial dysfunction and disease severity in COVID-19 patients: Evaluation by laser Doppler perfusion monitoring and cytokine/chemokine analysis

BACKGROUND

Microvascular dysfunction, serum cytokines and chemokines may play important roles in pathophysiology of coronavirus disease 2019 (COVID-19), especially in severe cases.

METHODS

Patients with COVID-19 underwent non-invasive evaluation of systemic endothelium-dependent microvascular reactivity - using laser Doppler perfusion monitoring in the skin of the forearm - coupled to local thermal hyperemia. Maximal microvascular vasodilatation (44 °C thermal plateau phase) was used as endpoint. A multiplex biometric immunoassay was used to assess a panel of 48 serum cytokines and chemokines. Severe COVID-19 (S-COVID) was defined according to WHO criteria, while all other cases of COVID-19 were considered mild to moderate (M-COVID). A group of healthy individuals who tested negative for SARS-CoV-2 served as a control group and was also evaluated with LDPM.

RESULTS

Thirty-two patients with COVID-19 (25% S-COVID) and 14 controls were included. Basal microvascular flow was similar between M-COVID and controls (P = 0.69) but was higher in S-COVID than in controls (P = 0.005) and M-COVID patients (P = 0.01). The peak microvascular vasodilator response was markedly decreased in both patient groups (M-COVID, P = 0.001; S-COVID, P < 0.0001) compared to the healthy group. The percent increases in microvascular flow were markedly reduced in both patient groups (M-COVID, P < 0.0001; S-COVID, P < 0.0001) compared to controls. Patients with S-COVID had markedly higher concentrations of dissimilar proinflammatory cytokines and chemokines, compared to patients with M-COVID.

CONCLUSIONS

In patients with COVID-19, especially with S-COVID, endothelium-dependent microvascular vasodilator responses are reduced, while serum cytokines and chemokines involved in the regulation of vascular function and inflammation are increased.

Attenuating Effects of Dieckol on Endothelial Cell Dysfunction via Modulation of Th17/Treg Balance in the Intestine and Aorta of Spontaneously Hypertensive Rats

Disruptions of the Treg/Th17 cell balance and gut barrier function are associated with endothelial dysfunction. Dieckol (DK) obtained from Ecklonia cava and E. cava extract (ECE) decreases blood pressure by reducing inflammation; however, it has not been elucidated whether DK or ECE modulates the Treg/Th17 balance, changes the gut epithelial barrier, or decreases endothelial cell dysfunction. We evaluated the effects of ECE and DK on gut barrier and the Treg/Th17 balance in the intestine and aorta, with regard to endothelial dysfunction, using the spontaneously hypertensive rat (SHR) model. The level of Th17 cells increased and that of Treg cells decreased in the intestine of SHRs compared to normotensive Wistar Kyoto (WKY) rat. These changes were attenuated by ECE or DK treatment. Additionally, the serum IL-17A level increased in SHRs more than WKY; this was decreased by ECE or DK treatment. The level of Treg cells decreased and that of Th17 cells increased in the aorta of SHRs. These changes were attenuated by ECE or DK treatment. The NF-κB and IL-6 levels were increased in SHRs, but these changes were reversed by ECE or DK treatment. Endothelial cell dysfunction, which was evaluated using peNOS/eNOS, nitrate/nitrite ratio, and NADPH oxidase activity, increased in the aorta of SHRs, but was decreased by ECE or DK treatment. The Treg/Th17 balance in the intestine and aorta of SHRs was attenuated and endothelial cell dysfunction was attenuated through the Th17/NF-κB/IL-6 pathway by ECE or DK.

May the analysis of 1918 influenza pandemic give hints to imagine the possible magnitude of Corona Virus Disease-2019 (COVID-19)?

BACKGROUND

In 1918 an unknown infectious agent spread around the world infecting over one-third of the general population and killing almost 50 million people. Many countries were at war, the First World War. Since Spain was a neutral country and Spanish press could report about the infection without censorship, this condition is commonly remembered as "Spanish influenza". This review examines several aspects during the 1918 influenza pandemic to bring out evidences which might be useful to imagine the possible magnitude of the present coronavirus disease 2019 (COVID-19).

METHODS

In the first part of this review we will examine the origin of the SARS-Coronavirus-2 and 1918 Spanish Influenza Virus and the role played by host and environment in its diffusion. We will also include in our analysis an evaluation of different approaches utilized to restrain the spread of pandemic and to treat infected patients. In the second part, we will try to imagine the magnitude of the present COVID-19 pandemic and the possible measures able to restrain in the present environment its spread.

RESULTS

Several factors characterize the outcome in a viral pandemic infection. They include the complete knowledge of the virus, the complete knowledge of the host and of the environment where the host lives and the pandemic develops.

CONCLUSION

By comparing the situation seen in 1918 with the current one, we are now in a more favourable position. The experience of the past teaches us that their success is linked to a rapid, constant and lasting application. Then, rather than coercion, awareness of the need to observe such prevention measures works better.

Characterization of the IL-17 and CD4+ Th17 Cells in the Clinical Course of Dengue Virus Infections

The aims of this study were to determine the involvement of interleukin 17 (IL-17) and IL-17-producing cells in dengue pathogenesis. Blood samples from dengue virus (DENV)-infected patients were collected on different days after the onset of symptoms. Patients were classified according to 1997 World Health Organization guidelines. Our study examined 152 blood samples from dengue fever (DF, n = 109) and dengue hemorrhagic fever (DHF, n = 43) patients and 90 blood samples from healthy controls (HC). High serum concentrations of IL-17A and IL-22 were also associated with DHF (IL-17A [DHF vs. DF, p < 0.01; DHF vs. HC, p < 0.0001]; IL-22 [DHF vs. DF, p < 0.05; DHF vs. HC, p < 0.0001]). Moreover, there was a positive correlation between serum levels of IL-17A and IL-23, a key cytokine that promotes IL-17-based immune responses (r = 0.4089, p < 0.0001). Consistent with the IL-17-biased immune response in DHF patients, we performed ex vivo activation of peripheral blood mononuclear cells (PBMCs) from DHF patients and flow cytometry analysis showed a robust IL-17-biased immune response, characterized by a high frequency of CD4+IL-17+ producing cells. Our results suggests IL-17-producing cells and their related cytokines can play a prominent role in this viral disease.

Paeoniflorin-6'-o-benzene sulfonate (CP-25) improves vasculitis through inhibiting IL-17A/JAK/STAT3 signaling pathway in endothelial cells of HFD CIA rats

Rheumatoid arthritis (RA) is a chronic autoimmune disease that affects not only joints but also multiple organ systems including cardiovascular system. Endothelial dysfunction plays an important role in cardiovascular diseases (CVD). In RA, endothelial dysfunction exists at both the macrovascular and the microvascular levels, which is a precursor to vasculitis. This study aimed to investigate the pathogenesis of vasculitis and the therapeutic effect of CP-25 on vasculitis in high-fat diet (HFD) collagen-induced arthritis (CIA) rats. Experimental groups were divided into normal group, HFD group, CIA group, HFD CIA group, CP-25 group and MTX group. In vitro, IL-17A was used to stimulate human umbilical vein endothelial cells (HUVECs), and then CP-25 was used to intervene. Results showed that CP-25 reduced global scoring (GS), arthritis index (AI), and swollen joint count (SJC) scores, improved histopathological score, reduced T cells percentage, and decreased IL-17A and ICAM-1 levels. Besides, CP-25 reduced the expression of p-STAT3 to normal levels in vascular of HFD CIA rats. In vitro, IL-17A promoted the expression of p-JAK1, p-JAK2, p-JAK3, pSTAT3, and ICAM-1, and CP-25 inhibited the expression of p-JAK1, p-JAK2, p-JAK3, p-STAT3, and ICAM-1. In conclusion, CP-25 might inhibit endothelial cell activation through inhibiting IL-17A/JAK/STAT3 signaling pathway, which improves vasculitis in HFD CIA rats.

Microvascular endothelial dysfunction in rheumatoid arthritis

The systemic autoimmune disease rheumatoid arthritis (RA) is characterized by increased cardiovascular mortality and morbidity and is an independent cardiovascular risk factor. Cardiovascular diseases (CVDs) result from accelerated atherogenesis, which is a consequence of endothelial dysfunction in the early stages of the disease. Endothelial dysfunction is a functional and reversible alteration of endothelial cells and leads to a shift in the properties of the endothelium towards reduced vasodilation, a pro-inflammatory state, and proliferative and prothrombotic properties. In RA, endothelial dysfunction can occur in the large vessels (such as the conduit arteries) and in the small vessels of the microvasculature, which supply oxygen and nutrients to the tissue and control inflammation, repair and fluid exchange with the surrounding tissues. Growing evidence suggests that microvascular endothelial dysfunction contributes to CVD development, as it precedes and predicts the development of conduit artery atherosclerosis and associated risk factors. As such, numerous studies have investigated microvascular endothelial dysfunction in RA, including its link with disease activity, disease duration and inflammation, the effect of treatments on endothelial function, and possible circulating biomarkers of microvascular endothelial dysfunction. Such findings could have important implications in the cardiovascular risk management of patients with RA.

Regulation of Th17 Cytokine-Induced Osteoclastogenesis via SKI306X in Rheumatoid Arthritis

This study aimed to investigate the regulatory effect of SKI306X, a mixed extract of three herbs, in T helper (Th)17 cytokine-induced inflammation and joint destruction in rheumatoid arthritis (RA). Synovial fibroblasts were isolated from RA patients and cultured with Th17 cytokines including interleukin (IL)-17, IL-21, and IL-22 and SKI306X, and tumor necrosis factor (TNF)-α, IL-1β, and receptor activator of nuclear factor kappa-Β ligand (RANKL) expression and production were investigated using real-time PCR and ELISA of culture media. After peripheral blood (PB) cluster of differentiation (CD)14⁺ monocytes were cultured in media supplemented with Th17 cytokines and SKI306X, tartrate-resistant acid phosphatase positive (TRAP⁺) multinucleated giant cells (mature osteoclasts) were enumerated and gene expression associated with osteoclast maturation was assessed via real-time PCR analysis. After PB monocytes were co-cultured with IL-17-stimulated RA synovial fibroblasts in the presence of SKI306X, osteoclast differentiation was assessed. When RA synovial fibroblasts were cultured with IL-17, IL-21, and IL-22, TNF-α, IL-1β, and RANKL expression and production were increased; however, SKI306X reduced cytokine expression and production. When PB monocytes were cultured in media supplemented with Th17 cytokines, osteoclast differentiation was stimulated; however, SKI306X decreased osteoclast differentiation and osteoclast maker expression. When PB monocytes were co-cultured with IL-17-stimulated RA synovial fibroblasts, osteoclast differentiation was increased; however, SKI306X decreased osteoclast differentiation and osteoclast maker expression. SKI306X reduced Th17 cytokine-induced TNF-α, IL-1β, and RANKL expression and osteoclast differentiation, providing novel insights into adjuvant therapy for regulating inflammation and joint destruction in RA.

Losartan, but not Enalapril and Valsartan, Inhibits the Expression of IFN-γ, IL-6, IL-17F and IL-22 in PBMCs from Rheumatoid Arthritis Patients

Background:

Rheumatoid Arthritis (RA) is a chronic and inflammatory disease that affects about 1% of the world's population. Almost 70% of RA patients have a cardiovascular disease such as Systemic Arterial Hypertension (SAH). Inflammatory cytokines are clearly involved in the pathogenesis of RA and correlated with SAH.

Objective:

It is necessary to understand whether the antihypertensive drugs have a dual effect as immunomodulators and which one is the best choice for RA SAH patients.

Methods:

Peripheral Blood Mononuclear Cells (PBMCs) from 16 RA patients were purified and stimulated or not stimulated with anti-CD3 and anti-CD28 mAB and were treated with Enalapril, Losartan and Valsartan at 100μM. Patients were evaluated for clinical and laboratory variables including measures of disease activity by Clinical Disease Activity Index (CDAI) and Disease Activity Score (DAS28). Cytokines were quantified by ELISA sandwich.

Results:

Losartan was able to reduce levels of IFN-γ (p = 0.0181), IL-6 (p = 0.0056), IL-17F (0.0046) and IL-22 (p = 0.0234) in RA patients. In addition, patients in remission and mild score (DAS28<3.2 and CDAI<10) had a better response to treatment. On the other hand, patients in moderate and severe activity had poor response to Losartan in cytokine inhibition.

Conclusion:

PBMCs from RA patients are responsive in inhibiting proinflammatory cytokines using Losartan better than Enalapril and Valsartan and it could be a better antihypertensive choice for patients with RA and systemic arterial hypertension treatment.

From blood coagulation to innate and adaptive immunity: the role of platelets in the physiology and pathology of autoimmune disorders

Thrombosis and cardiovascular complications are common manifestations of a variety of pathological conditions, including infections and chronic inflammatory diseases. Hence, there is great interest in determining the hitherto unforeseen immune role of the main blood coagulation executor-the platelet. Platelets store and release a plethora of immunoactive molecules, generate microparticles, and interact with cells classically belonging to the immune system. The observed effects of platelet involvement in immune processes, especially in autoimmune diseases, are conflicting-from inciting inflammation to mediating its resolution. An in-depth understanding of the role of platelets in inflammation and immunity could open new therapeutic pathways for patients with autoimmune disorders. This review aims to summarize the current knowledge on the role of platelets in the patomechanisms of autoimmune disorders and suggests directions for future research.

Modeling of the effects of IL-17 and TNF-α on endothelial cells and thrombus growth

Rheumatoid and psoriatic arthritis are chronic inflammatory diseases, with massive increase of cardiovascular events (CVE), and contribution of the cytokines TNF-α and IL-17. Chronic inflammation inside the joint membrane or synovium results from the activation of fibroblasts/synoviocytes, and leads to the release of cytokines from monocytes (Tumor Necrosis Factor or TNF) and from T lymphocytes (Interleukin-17 or IL-17). At the systemic level, the very same cytokines affect endothelial cells and vessel wall. We have previously shown [1,2] that IL-17 and TNF-α, specifically when combined, increase procoagulation, decrease anticoagulation and increase platelet aggregation, leading to thrombosis. These results are the basis for the models of interactions between IL-17 and TNF, and genes expressed by activated endothelial cells. This work is devoted to mathematical modeling and numerical simulations of blood coagulation and clot growth under the influence of IL-17 and TNF-α. We show that they can provoke thrombosis, leading to the complete or partial occlusion of blood vessels. The regimes of blood coagulation and conditions of occlusion are investigated in numerical simulations and in approximate analytical models. The results of mathematical modeling allow us to predict thrombosis development for an individual patient.

Alteration of plasma cytokines in patients with active epilepsy

OBJECTIVE

Emerging evidence suggests that inflammatory cytokines are involved in pathophysiology of epilepsy. However, possible interaction between the cytokines and active epilepsy remains unclear. This study aimed to interictal and postictal plasma cytokines in active epilepsy patients.

MATERIALS AND METHODS

We enrolled 48 patients with active epilepsy and 30 healthy adults and measured postictal and interictal interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interferon gamma (IFN-γ), interleukin-10 (IL-10), and interleukin-17A (IL-17A) concentrations in peripheral blood by enzyme-linked immunosorbent assay (ELISA).

RESULTS

We found postictal and interictal concentrations of IL-6, IL-17A, and IFN-γ were significantly elevated in epilepsy patients compared with healthy controls. There were no significant postictal and interictal alterations of IL-1β, IL-6, TNF-α, IFN-γ, IL-10, and IL-17A in patients with generalized seizures compared to those with partial seizures, in carbamazepine (CBZ)-treated patients compared to valproic acid (VPA)-treated patients or in temporal lobe epilepsy (TLE) patients compared to extra-temporal lobe epilepsy (eTLE) patients. Furthermore, multivariate linear regression analysis revealed that interictal IL-17A concentration positively correlated with National Hospital Seizure Severity Scale (NHS3) scores (B=0.092, P=.007) and seizure frequency (B=0.045, P=.000). Interictal IFN-γ concentration was also showed positively correlation with seizure frequency (B=0.019, P=.004).

CONCLUSIONS

Our data suggest that postictal and interictal various inflammatory cytokines are elevated in plasma of active epilepsy patients. Furthermore, interictal IL-17A and IFN-γ may predict seizure severity.

Secukinumab (AIN-457) for the treatment of Psoriasis

Secukinumab (also known as AIN-457) is a human monoclonal antibody targeting IL-17A, which has been recently FDA-approved for the treatment of moderate to severe psoriasis and psoriatic arthritis with coexistent moderate to severe plaque psoriasis based on clinical trials demonstrating excellent efficacy. This review will address the rationale for targeting the IL-23/Th17/IL-17 axis, the role of IL-17 and Th17 cells in psoriasis and other chronic inflammatory diseases, and will examine pre-clinical studies, pharmacologic properties, clinical efficacy, and the safety profile of secukinumab.

Endothelial progenitor cells: Are they displaying a function in autoimmune disorders?

Endothelial Progenitor Cells (EPCs) are bone marrow derived cells able to differentiate in mature endothelial cells (EC) contributing to the generation of new vessels, connecting to fibronectin, and forming colonies and/or colony forming units. Since circulating EPCs can be actively considered part of endothelial damage in several cardiovascular diseases and autoimmune disorders the possibility to have a measure for endothelium damage should be considered of interest to predict the patient out-come. At the same time the EPCs proliferative and regenerative role could be considered for therapeutic applications. Studies have been performed to elucidate the role of EPCs in Systemic Sclerosis and many review and articles published on this topic. In the present paper we aimed to review the role of EPCs in other autoimmune disorders.

Causes of changes in carotid intima-media thickness: a literature review

Atherosclerosis causes significant morbidity and mortality. Carotid intima-media thickness (CIMT) predicts future cardiovascular and ischaemic stroke incidence. CIMT, a measure of atherosclerotic disease, can be reliably determined in vivo by carotid ultrasound. In this review, we determined that CIMT is associated with traditional cardiovascular risk factors such as age, sex, race, smoking, alcohol consumption, habitual endurance exercise, blood pressure, dyslipidemia, dietary patterns, risk-lowering drug therapy, glycemia, hyperuricemia, obesity-related anthropometric parameters, obesity and obesity-related diseases. We also found that CIMT is associated with novel risk factors, including heredity, certain genotypic indices, anthropometric cardiovascular parameters, rheumatoid arthritis, immunological diseases, inflammatory cytokines, lipid peroxidation, anthropometric hemocyte parameters, infectious diseases, vitamin D, matrix metalloproteinases, and other novel factors and diseases. However, the conclusions are inconsonant; the underlying causes of these associations remain to be further explored.

Increased Rheumatoid Factor and Deep Venous Thrombosis: 2 Cohort Studies of 54628 Individuals from the General Population

BACKGROUND

The risk of deep venous thrombosis is increased in patients with rheumatoid arthritis. We tested the hypothesis that increased concentrations of rheumatoid factor are associated with increased risk of deep venous thrombosis in individuals without autoimmune rheumatic disease in the general population.

METHODS

We included 54628 participants from the Copenhagen City Heart Study (1981–83) and the Copenhagen General Population Study (2004–12), all with a measured concentration of IgM rheumatoid factor and without autoimmune rheumatic disease or venous thromboembolism. The main outcome was incident deep venous thrombosis. There were no losses to follow-up.

RESULTS

During 368381 person-years, 670 individuals developed deep venous thrombosis. A rheumatoid factor concentration ≥ vs &lt;110 IU/mL showed the strongest association with deep venous thrombosis, with multivariable adjusted hazard ratios of 9.0 (95% CI 3.1–26) for 1-year follow-up, 4.3 (2.2–8.5) for 5-year follow-up, and 3.1 (1.7–5.6) for up to 32 years of follow-up. Compared with rheumatoid factor concentrations &lt;15 IU/mL, the multivariable adjusted hazard ratios for deep venous thrombosis during maximum follow-up were 1.3 (1.0–1.5) for 15–29 IU/mL, 1.7 (1.0–2.8) for 30–59 IU/mL, 2.4 (1.3–4.3) for 60–119 IU/mL, and 3.0 (1.6–5.6) for ≥120 IU/mL (trend P = 6 × 10−7). Results were similar in the 2 studies separately. Obese men and women age &gt;60 years with rheumatoid factor concentrations ≥120 IU/mL had 10% and 8% 5-year risk of deep venous thrombosis.

CONCLUSIONS

Increased rheumatoid factor in the general population was associated with up to 3-fold increased long-term risk and up to 9-fold increased 1-year risk of deep venous thrombosis.

Rheumatoid arthritis pathophysiology: update on emerging cytokine and cytokine-associated cell targets

Biologic therapies that target pathogenic cytokines such as TNF, IL-1β or IL-6 have greatly improved the treatment of RA. Unfortunately, not all RA patients respond to current biologic therapies and responses are not always maintained, suggesting that there are alternative drivers of RA pathogenesis that might serve as promising therapeutic targets. Discovery of the new Th17 subset of Th cells, and their role in autoimmune disease development, has implicated the proinflammatory IL-12 and IL-17 families of cytokines in RA disease pathogenesis. Members of these cytokine families are elevated in the blood and joints of RA patients and have been shown to remain elevated in patients who do not respond to current biologics. In addition, these cytokines have been shown to play roles in joint destruction and erosion. A new subclass of biologics that target the IL-12 and/or IL-17 signalling pathways are under development. Here we review evidence for a role of Th17 cells as well as IL-12 and IL-17 cytokines in RA pathogenesis as the rationale for a subsequent discussion of the ongoing and completed clinical trials of newly emerging biologic therapies directed at IL-12 or IL-17 pathway inhibition.

Interleukin-17A Exacerbates Ferric Chloride-Induced Arterial Thrombosis in Rat Carotid Artery

Interleukin-17A (IL-17A), the most widely studied member of the IL-17 cytokine family, is a cytokine which emerged to be critical for host defense as well as in the pathogenesis of autoimmune disorders. Moreover, IL-17A is involved in the pathogenesis of cardiovascular diseases, such as atherosclerosis and acute coronary syndrome and in the cardiovascular risk associated with systemic immunological disorders. Consistent with this, we have recently shown that IL-17A increases human and murine platelet response to ADP. In this study we expanded our previous observation and we describe for the first time an in vivo prothrombotic effect of the cytokine. Our results show that IL-17A is synergic with a low FeCl₃ concentration in inducing carotid thrombus in rats and suggest that the effect is likely related to a downregulation of CD39 vascular expression and hydrolyzing activity. Our findings indicate that IL-17A might be an important molecule at the interface between hemostasis and inflammation.

“This paper is dedicated to the memory of Professor Alfredo Colonna”

Improving cardiovascular outcomes in rheumatic diseases: therapeutic potential of circulating endothelial progenitor cells

Patients with Rheumatoid Arthritis (RA) and Systemic Lupus Erythematosus (SLE) have a significantly increased risk of cardiovascular disease (CVD). The reason for this is unclear but may be due, at least in part, to the failure of endothelial repair mechanisms. Over the last 15 years there has been much interest in the mechanisms of endothelial renewal and its potential as a therapy for CVD. In the circulation there are two distinct populations of cells; myeloid angiogenic cells (MACs) which augment repair by the paracrine secretion of angiogenic factors, and outgrowth endothelial cells (OECs) which are true endothelial progenitor cells (EPCs) and promote vasculogenesis by differentiating into mature endothelium. There are marked abnormalities in the number and function of these cells in patients with RA and SLE. Inflammatory cytokines including interferon-alpha (IFNα) and tumour-necrosis factor alpha (TNFα) both impair MAC and OEC function ex vivo and may therefore contribute to the CVD risk in these patients. Whilst administration of mononuclear cells, MACs and other progenitors has improved cardiovascular outcomes in the acute setting, this is not a viable option in chronic disease. The pharmacological manipulation of MAC/OEC function in vivo however has the potential to significantly improve endothelial repair and thus reduce CVD in this high risk population.

The peroxisome proliferator activated receptor-γ pioglitazone improves vascular function and decreases disease activity in patients with rheumatoid arthritis

Background

Rheumatoid arthritis (RA) is associated with heightened mortality due to atherosclerotic cardiovascular disease (CVD). Inflammatory pathways in RA negatively affect vascular physiology and promote metabolic disturbances that contribute to CVD. We hypothesized that the peroxisome proliferator activated receptor‐γ (PPAR‐γ) pioglitazone could promote potent vasculoprotective and anti‐inflammatory effects in RA.

Methods and Results

One hundred forty‐three non‐diabetic adult RA patients (76.2% female, age 55.2±12.1 [mean±SD]) on stable RA standard of care treatment were enrolled in a randomized, double‐blind placebo controlled crossover trial of 45 mg daily pioglitazone versus placebo, with a 3‐month duration/arm and a 2‐month washout period. Pulse wave velocity of the aorta (PWV), brachial artery flow mediated dilatation (FMD), nitroglycerin mediated dilatation (NMD), microvascular endothelial function (reactive hyperemia index [RHI]), and circulating biomarkers of inflammation, insulin resistance, and atherosclerosis risk all were quantified. RA disease activity was assessed with the 28‐Joint Count Disease Activity Score (DAS‐28) C‐reactive protein (CRP) and the Short Form (36) Health Survey quality of life questionnaire. When added to standard of care RA treatment, pioglitazone significantly decreased pulse wave velocity (ie, aortic stiffness) (P=0.01), while FMD and RHI remained unchanged when compared to treatment with placebo. Further, pioglitazone significantly reduced RA disease activity (P=0.02) and CRP levels (P=0.001), while improving lipid profiles. The drug was well tolerated.

Conclusions

Addition of pioglitazone to RA standard of care significantly improves aortic elasticity and decreases inflammation and disease activity with minimal safety issues. The clinical implications of these findings remain to be established.

Clinical Trial Registration

URL: ClinicalTrials.gov Unique Identifier: NCT00554853.

Burden of disease: psoriasis and psoriatic arthritis

Psoriatic arthritis (PsA) increases the disease burden associated with psoriasis by further diminishing quality of life, increasing health care costs and cardiovascular risk, and potentially causing progressive joint damage. The presence of PsA influences psoriasis treatment by increasing overall disease complexity and, within the framework of current guidelines and recommendations, requiring the use of conventional disease-modifying anti-rheumatic drugs or tumor necrosis factor-α inhibitors in order to prevent progressive joint damage. Despite its important impact, PsA is still under-diagnosed in dermatology practice. Dermatologists are well positioned to recognize and treat PsA, given that it characteristically presents, on average, 10 years subsequent to the appearance of skin symptoms. Regular screening of psoriasis patients for early evident joint symptoms should be incorporated into daily dermatologic practice. Although drugs effective in PsA are available, not all patients may respond to treatment, and others may lose their initial response over time. New investigational therapies, such as inhibitors of interleukin-17A, interleukin-12/23, Janus kinase 3, or phosphodiesterase-4, may address unmet needs in psoriatic disease, with further research needed to determine the role of these agents in reducing joint damage and other comorbidities.

Burden of disease in treated rheumatoid arthritis patients: going beyond the joint

OBJECTIVE

The disease burden in rheumatoid arthritis (RA) extends beyond the joint. This article evaluates the physical and psychosocial extra-articular burden of treated RA and relationships among diverse disease manifestations.

METHODS

MEDLINE searches identified papers published in English from January 2003 to December 2012 that evaluated systemic complications and psychosocial aspects associated with RA. Preference was given to studies with randomized cohorts and large (>100) sample sizes. Of 378 articles identified in the initial search, 118 were selected for inclusion.

RESULTS

RA is associated with multiple comorbidities and psychosocial impairments, including cardiovascular disease, osteoporosis, interstitial lung disease, infection, malignancies, fatigue, depression, cognitive dysfunction, reduced work performance, work disability, and decreased health-related quality of life. The etiology of the extra-articular burden may reflect the systemic inflammation and immune system alteration associated with RA, metabolic imbalances and side effects related to treatment, or the influence of comorbidities. Strategies that may help to reduce the extra-articular disease burden include personalized medicine and the potential introduction of treatments with new mechanisms of action.

CONCLUSION

Despite improvements in treating joint disease, the extra-articular burden in RA remains substantial, encompassing multiple comorbidities and psychosocial impairments.

NETs are a source of citrullinated autoantigens and stimulate inflammatory responses in rheumatoid arthritis

The early events leading to the development of rheumatoid arthritis (RA) remain unclear, but formation of autoantibodies to citrullinated protein antigens (ACPAs) is considered a key pathogenic event. Neutrophils isolated from patients with various autoimmune diseases display enhanced neutrophil extracellular trap (NET) formation, a phenomenon that exposes autoantigens in the context of immunostimulatory molecules. We investigated whether aberrant NETosis occurs in RA, determined its triggers, and examined its deleterious inflammatory consequences. Enhanced NETosis was observed in circulating and RA synovial fluid neutrophils compared to neutrophils from healthy controls and from patients with osteoarthritis (OA). Further, netting neutrophils infiltrated RA synovial tissue, rheumatoid nodules, and skin. NETosis correlated with ACPA presence and levels and with systemic inflammatory markers. RA sera and immunoglobulin fractions from RA patients with high levels of ACPA and/or rheumatoid factor significantly enhanced NETosis, and the NETs induced by these autoantibodies displayed distinct protein content. Indeed, during NETosis, neutrophils externalized the citrullinated autoantigens implicated in RA pathogenesis, and anti-citrullinated vimentin antibodies potently induced NET formation. Moreover, the inflammatory cytokines interleukin-17A (IL-17A) and tumor necrosis factor-α (TNF-α) induced NETosis in RA neutrophils. In turn, NETs significantly augmented inflammatory responses in RA and OA synovial fibroblasts, including induction of IL-6, IL-8, chemokines, and adhesion molecules. These observations implicate accelerated NETosis in RA pathogenesis, through externalization of citrullinated autoantigens and immunostimulatory molecules that may promote aberrant adaptive and innate immune responses in the joint and in the periphery, and perpetuate pathogenic mechanisms in this disease.

Vitamin D deficiency, interleukin 17, and vascular function in rheumatoid arthritis

OBJECTIVE

Vitamin D deficiency is associated with increased cardiovascular (CV) disease risk in the general population. We examined the association between vitamin D deficiency and CV risk in rheumatoid arthritis (RA).

METHODS

We measured large artery compliance by pulse wave velocity and microvascular function by the reactive hyperemia index in patients with stable RA (n = 87). We quantified CV risk factors, serum 25-hydroxyvitamin D [25(OH)D], and interleukin 17 (IL-17), and RA disease activity by Disease Activity Score of 28 joints. We used linear regression to test associations between serum 25(OH)D and CV risk factors.

RESULTS

The mean serum 25(OH)D level in the cohort was 27.1 ± SD 13.6 ng/ml. Fifty-nine patients (68%) were vitamin D-insufficient (25(OH)D < 30 ng/ml; mean 20.2 ± 5.9 ng/ml) and of these, 25 (29%) were vitamin D-deficient (25(OH)D < 20 ng/ml; mean 14.4 ± 3.4 ng/ml). In the whole cohort and the vitamin D-insufficient group, serum 25(OH)D was inversely associated with IL-17 (log IL-17; β = -0.83, p = 0.04; β = -0.63, p = 0.004, respectively) by univariate analysis, which persisted after adjustment for season, and in multivariate analysis after adjustment for confounders (log IL-17; β = -0.74, p = 0.04; β = -0.53, p = 0.02). In vitamin D-deficient patients, serum 25(OH)D was positively associated with microvascular function by univariate and multivariate analysis after adjustment for confounders (β = 2.1, p = 0.04; β = 2.7, p = 0.04).

CONCLUSION

Vitamin D deficiency in RA may affect Th17 responses and microvascular function. Maintaining normal serum vitamin D levels may protect against IL-17-mediated inflammation and vascular dysfunction in RA.

Functional consequences of platelet binding to T lymphocytes in inflammation

Expression of the scavenger receptor CD36 on lymphocytes is intriguing. We observed that a minor subpopulation of lymphocytes expressed CD36 on the cell surface. We investigated the source of CD36 and also the proliferation and cytokine production of these CD36(+) CD4(+) lymphocytes. Flow cytometry analysis and immunofluorescence microscopy showed that CD36(+) platelets were responsible for CD36 detection on lymphocytes. CD36 was then used as a tool to characterize lymphocytes with bound platelets. Activation-induced proliferation was lower in CD4(+) lymphocytes with bound platelets than lymphocytes without bound platelets. IL-17 and IFN-γ production was also reduced in lymphocytes with bound platelets. We then studied the presence of CD36(+) CD4(+) lymphocytes in RA patients. We observed that the percentage of CD4(+) lymphocytes with bound platelets was higher on RA patients than in healthy donors. RA patients with higher titers of anti-CCP, RF levels, and cardiovascular risk index presented a lower percentage of CD4(+) lymphocytes with bound platelets. These patients also had higher IL-17 and IFN-γ production. These results suggest that platelet-binding modifies lymphocyte function. This binding could be a regulatory mechanism in RA that confers a less severe phenotype.

Circulating levels of TNF-like cytokine 1A correlate with the progression of atheromatous lesions in patients with rheumatoid arthritis

Interactions between TNF-like Cytokine 1A (TL1A) and its receptors, death receptor-3 (DR3) and decoy receptor-3 (DcR3) may be important in atherogenesis. We hypothesized that dysregulation of this system predicts formation of new atheromatic plaques in rheumatoid arthritis (RA). Forty-five patients were prospectively followed up for 40.5 ± 3.6 months. Serum concentrations of TL1A and DcR3 were measured at baseline and carotid and femoral arteries examined by ultrasound at baseline and at the end of follow-up. Individual serum levels of TL1A correlated with the progression of carotid atheromatic plaque height (Spearman rho = 0.550, p = 0.003). Patients with low TL1A and undetectable DcR3 serum levels at baseline showed significantly fewer newly formed carotid plaques during the next 3.5 years than the remaining patients (P = 0.016). Univariate analysis showed that a "low TL1A/DcR3" immunophenotype predicted a preserved atherosclerosis profile in carotid (P = 0.026), or carotid and/or femoral arteries (P = 0.022). Dysregulated TL1A-induced signaling may be associated with risk for accelerated atherosclerosis in RA.

Targeting IL-17 and TH17 cells in chronic inflammation

The key role of interleukin-17 (IL-17) and T helper 17 (T(H)17) cells in tissue inflammation, autoimmunity and host defence led to the experimental targeting of these molecules in mouse models of diseases as well as in clinical settings. Moreover, the demonstration that IL-17 and T(H)17 cells contribute to local and systemic aspects of disease pathogenesis, as well as the finding that the IL-17-T(H)17 cell pathway is regulated by IL-23, prompted the identification of inhibitors. These inhibitors include biotechnology products that target IL-23 as well as the leading member of the IL-17 family, IL-17A, and one of its receptors, IL-17 receptor A. Several clinical trials of these inhibitors are underway, and positive results have been obtained in psoriasis, rheumatoid arthritis and ankylosing spondylitis. This Review focuses on the current knowledge of the IL-17-T(H)17 cell pathway to better understand the positive as well as potential negative consequences of targeting them.

Mechanisms of premature atherosclerosis in rheumatoid arthritis and lupus

Rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), the two most common systemic autoimmune disorders, have both unique and overlapping manifestations. One feature they share is a significantly enhanced risk of atherosclerotic cardiovascular (CV) disease that significantly contributes to morbidity and mortality. The primary mechanisms that drive CV damage in these diseases remain to be fully characterized, but recent discoveries indicate that distinct inflammatory pathways and immune dysregulation characteristic of RA and SLE likely play prominent roles. This review focuses on analyzing the major mechanisms and pathways potentially implicated in the acceleration of atherothrombosis and CV risk in SLE and RA, as well as in the identification of putative preventive strategies that may mitigate vascular complications in systemic autoimmunity.

Atherosclerosis and rheumatoid arthritis: more than a simple association

In the last decades a large amount of evidence linked rheumatoid arthritis (RA) to atherosclerosis. In fact, RA patients have an increased risk of cardiovascular events that is not fully explained by other classic cardiovascular risk factors. RA and atherosclerosis may share several common pathomechanisms and inflammation undoubtedly plays a primary role. The proinflammatory cytokines such as tumor necrosis factor alpha and interleukin-6, involved in the pathogenesis of RA, are also independently predictive of subsequent cardiovascular disease (CVD). In RA, inflammation alters HDL constituents and the concentration of LDL and HDL, thus facilitating atherosclerosis and CVD events. On the other hand, also the increase of oxidative processes, frequently observed in RA, induces atherosclerosis. Interestingly, some genetic polymorphisms associated with RA occurrence enhance atherosclerosis, however, other polymorphisms associated with RA susceptibility do not increase CVD risk. Several other mechanisms may influence atherosclerotic processes in RA. Moreover, atherosclerosis may be directly mediated also by underlying autoimmune processes, and indirectly by the occurrence of metabolic syndrome and impaired physical activity. Finally, the effects of RA therapies on cardiovascular system in general and on atherosclerosis in particular are really wide and different. However, the starting point of every RA treatment is that disease control, or better remission, is the best way we have for the reduction of CVD occurrence.

Interaction between smoking and HLA-DRB1*04 gene is associated with a high cardiovascular risk in Brazilian Amazon patients with rheumatoid arthritis

Background

Rheumatoid Arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joints that affects approximately 1% of the population worldwide. The HLA-DRB1 gene locus plays a major role in genetic susceptibility to RA, a condition that has been associated with a high cardiovascular morbidity and mortality in many studies.

Methodology/Principal Findings

The aim of this work was to investigate which types of HLA class II genes are associated with RA in patients from the Brazilian Amazon and their influence on high cardiovascular risk status in this population. For this purpose, a case-control study was carried out with a total of 350 non-Indian individuals made up of a cohort of 132 consecutive RA sufferers and 218 healthy controls. A χ² test showed that HLADRB1*04 (p<0.0016; OR = 1.89; 95% CI = 1.29–2.79) and HLADRB1*10 (p = 0.0377; OR = 3.81; 95% CI = 1.16–12.50) are the major HLA genes associated with susceptibility to RA. A logistic regression model also showed that the interaction between HLADRB1*04 (p = 0.027; OR = 6.02; 95% CI = 1.21–29.7), age (p = 0.0001; OR = 1.26; 95% CI = 1.13–1.39) and smoking (p = 0.0001; OR = 23.6; 95% CI = 4.25–32.1) is associated with a probability of a high cardiovascular risk status at an early age.

Conclusions/Significance

The results of this study show for the first time that HLA class II type is associated with RA in Brazilian Amazon populations and that a specific interaction between the HLA-DRB1*04 gene and smoking is associated with a high cardiovascular risk status, as initially reported in the European population. This study therefore contributes to an understanding of gene-environment interactions in RA patients.