La fibrose rétropéritonéale, une maladie inflammatoire méconnue. Observations cliniques et revue de la littérature [Retroperitoneal fibrosis, an unrecognized inflammatory disease. Clinical observations and review of the literature]

Retroperitoneal fibrosis (RF) is a rare disease, typically with an insidious clinical course. The peak incidence is seen in patients 40 to 60 years of age and mostly in man. The characteristic finding in this disease is a periaortic fibrous mass that often surrounds the ureters. Although usually regarded as an obstructive uropathy, there has been growing recognition of the condition as a generalized disease. It may have a wide variety of manifestations including mediastinitis, thyroiditis and sclerosing cholangitis. The most common mode of presentation remains abdominal or flank pain with uremia, anemia and a high sedimentation rate. Although ultrasound and renal scintigraphy may contribute to the general evaluation of patients with RF, CT-scanner is the preferred imaging method. The multiplanar imaging capability of magnetic resonance may facilitate assessment of disease extent. The pathogenesis of the disease remains unknown. Steroids and, more recently tamoxifen, appear to be effective in the treatment of the RF. In most instances, RF does not lead to long-term morbidity or affect survival. The three cases of RF reported herein illustrate the varied mode of presentation and the response to the treatment.

Role of biological agents in auto-inflammatory disease in children

BACKGROUND: Biological agents (BA) have recently completed the treatment options in auto-inflammatory diseases (AID) in children with the aim to improve the outcome. TNF-α blocking agents have been the first BA successfully used in children. However, other biological agents targeting cytokines including IL-1 and IL-6 have been shown to be effective (anti-IL-1/6), especially in AID like systemiconset juvenile arthritis (SoJIA) or cryopyrine-associated periodic syndrome (CAPS). In Switzerland, Etanercept has been approved for the treatment of JIA since 2000 and Canakinumab for the treatment of paediatric CAPS since 2009.OBJECTIVES: Evaluation of the use of biological agents in AID in Western Switzerland.METHODS: We selected all patients with AID seen in the Réseau Romand de Rhumatologie Pédiatrique (Lausanne, Geneva, Aigle, Sion, and Neuchâtel) who were treated with the following BA: anti-TNF-α (Etanercept, Infliximab, Adalimumab) and Abatacept, and anti-IL-1/6 (Anakinra, Canakinumab, Tocilizumab). We looked at minor and major adverse events and the activity of the disease before and after treatment with BA and with special regards on anti-IL-1/6.RESULTS: Among 921 children and adolescents followed between 2004 and 2010, we selected 85 patients with AID (PFAPA: 40, FMF: 6, HyperIgD: 1, CAPS: 3, SoJIA: 34). Only patients with CAPS and SoJIA were treated with BA. They had a mean age of 9 years (3-22) and F: M ratio of 1.6:1. 7 patients were treated with one BA, 6 patients with 2 different BAs and 3 with 3 BAs. 3 patients with CAPS were treated with anti-IL-1 and responded very well. 13 SoJIA patients were treated with BA (anti-TNF-α: 8, Abatacept: 1, anti-IL-1/6: 8). 4 patients treated by anti-TNF-α were switched to anti-IL-1/6 because of lack of response to treatment (cf Table 1). We did not have any serious adverse events and no serious infections.CONCLUSIONS: Patients with SoJIA and CAPS clearly benefit from treatment with BA. General tolerance was good. In the CAPS group the response to IL-1 was excellent. In SoJIA, 3/4 patients, switched from anti-TNF-α to anti-IL-1/6 for lack of therapeutic response, did not respond well to the second medication. These patientsseem to represent a population relatively resistant to treatment with BA. Due to the low number of patients in our cohort, the response to BA in SoJIA patients non-responder to anti- TNF-α agents should be further studied.

Atteintes cardiaques dans les connectivites: l'exemple du lupus érythémateux systémique [Cardiac involvement in connective tissue disease: the example of systemic lupus erythematosus]

When we think of cardiac affection in the context of systemic lupus erythematosus (SLE), we usually refer to pericarditis first. As frequent as this affection is, it is actually not the only cardio-vascular problem that occurs with this systemic inflammatory disease. Are the cardiac events--ranging from multiple heart valve involvements to increased cardiovascular risks--clinically significant? And are they involving a specific follow-up, treatment or support? We are therefore trying to evaluate these questions in order to give some recommendations to any practitioners following up a lupus patient, or a patient suffering from any other inflammatory systemic disease.

Sarcoïdose extrapulmonaire: entité méconnue [Extrapulmonary sarcoidosis: an unrecognized disease entity?].

Sarcoidosis is a multi-systemic inflammatory disease of unknown etiology, histologically characterized by the presence of non caseating granulomas. The diagnostic suspicion relies on clinical, epidemiological, biological and radiological elements. It is confirmed by an evocative histology and by the exclusion of other granulomatous pathologies. The aim of this article is to expose some clinical manifestations of extrapulmonary sarcoidosis particularly the cardiac and abdominal involvements. A register was made on cases of sarcoidosis diagnosed in CHUV from 2000 to 2009. It demonstrates the rarity of the disease in the region of Lausanne and confirms the existence of purely extra-thoracic affections.

Differential effects of selective HDAC inhibitors on macrophage inflammatory responses to the Toll-like receptor 4 agonist LPS.

Broad-spectrum inhibitors of HDACs are therapeutic in many inflammatory disease models but exacerbated disease in a mouse model of atherosclerosis. HDAC inhibitors have anti- and proinflammatory effects on macrophages in vitro. We report here that several broad-spectrum HDAC inhibitors, including TSA and SAHA, suppressed the LPS-induced mRNA expression of the proinflammatory mediators Edn-1, Ccl-7/MCP-3, and Il-12p40 but amplified the expression of the proatherogenic factors Cox-2 and Pai-1/serpine1 in primary mouse BMM. Similar effects were also apparent in LPS-stimulated TEPM and HMDM. The pro- and anti-inflammatory effects of TSA were separable over a concentration range, implying that individual HDACs have differential effects on macrophage inflammatory responses. The HDAC1-selective inhibitor, MS-275, retained proinflammatory effects (amplification of LPS-induced expression of Cox-2 and Pai-1 in BMM) but suppressed only some inflammatory responses. In contrast, 17a (a reportedly HDAC6-selective inhibitor) retained anti-inflammatory but not proinflammatory properties. Despite this, HDAC6(-/-) macrophages showed normal LPS-induced expression of HDAC-dependent inflammatory genes, arguing that the anti-inflammatory effects of 17a are not a result of inhibition of HDAC6 alone. Thus, 17a provides a tool to identify individual HDACs with proinflammatory properties.

Rethinking the triggering inflammatory processes of chronic periaortitis.

Chronic periaortitis (CP) is an uncommon inflammatory disease which primarily involves the infrarenal portion of the abdominal aorta. However, CP should be regarded as a generalized disease with three different pathophysiological entities, namely idiopathic retroperitoneal fibrosis (RPF), inflammatory abdominal aortic aneurysm and perianeurysmal RPF. These entities share similar histopathological characteristics and finally will lead to fibrosis of the retroperitoneal space. Beside fibrosis, an infiltrate with variable chronic inflammatory cell is present. The majority of these cells are lymphocytes and macrophages as well as vascular endothelial cells, most of which are HLA-DR-positive. B and T cells are present with a majority of T cells of the T-helper phenotype. Cytokine gene expression analysis shows the presence of interleukin (IL)-1alpha, IL-2, IL-4, interferon-gamma and IL-2 receptors. Adhesion molecules such as E-selectin, intercellular adhesion molecule-1 and the vascular cell adhesion molecule-1 were also found in aortic tissue, and may play a significant role in CP pathophysiology. Although CP pathogenesis remains unknown, an exaggerated inflammatory response to advanced atherosclerosis (ATS) has been postulated to be the main process. Autoimmunity has also been proposed as a contributing factor based on immunohistochemical studies. The suspected allergen may be a component of ceroid, which is elaborated within the atheroma. We review the pathogenesis and the pathophysiology of CP, and its potential links with ATS. Clinically relevant issues are summarized in each section with regard to the current working hypothesis of this complex inflammatory disease.

PFAPA syndrome is not a sporadic disease.

OBJECTIVES: To determine whether PFAPA (periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis) patients have a positive family history (FH) for recurrent fever syndromes. METHOD: For all patients with PFAPA seen in two paediatric rheumatology centres (Romandy, Switzerland and Bordeaux, France), parents were interviewed to record the FH for periodic fever. As controls, we interviewed a group of children without history of recurrent fever. RESULTS: We recruited 84 patients with PFAPA and 47 healthy children. The FH for recurrent fever (without an infectious cause and recurring for at least half a year) was positive in 38/84 (45%), and was positive for PFAPA (diagnosis confirmed by a physician) in 10/84 (12%) of the PFAPA patients. For 29 of the 38 patients with positive FH, the affected person was a sibling or a parent. None of the healthy children had a positive FH for recurrent fever or PFAPA. A positive FH for rheumatological diseases was seen in both groups of children. CONCLUSION: These data show that a significant percentage of PFAPA patients present a positive FH of recurrent fever and PFAPA. This familial susceptibility suggests a potential genetic origin for this syndrome.

Pathogenesis of adult-onset Still's disease: new insights from the juvenile counterpart.

Adult-onset Still's disease (AOSD) is a rare inflammatory disease characterized by the classical triad of daily fever, arthritis, and typical salmon-colored rash. Recent accumulation of knowledge, mostly arising from hereditary autoinflammatory diseases and from the systemic-onset juvenile idiopathic arthritis (sJIA), has given raise to new hypotheses on the pathophysiology of AOSD. In this review, we first discuss on the continuum between AOSD and sJIA. Then, we summarize current hypotheses on the underlying pathogenesis: (1) an infectious hypothesis; (2) an autoinflammatory hypothesis; (3) a lymphohistiocytic hypothesis; and (4) a hyperferritinemic hypothesis. Finally, we present the recent data suggesting that patients with AOSD fall into two distinct subgroups with different courses, one with prominent systemic features and one with chronic arthritis.

Systemic-onset juvenile idiopathic arthritis: the changing life of a rare disease.

Systemic-onset juvenile idiopathic arthritis (SoJIA), sometimes called Still's disease, is a systemic inflammatory disease classified within the spectrum of juvenile idiopathic arthritis (JIA). It is an orphan disease with often a chronic course and a major impact on the affected children and their families. This disorder is unique in terms of clinical manifestations, prognosis and response to conventional immunosuppressants. The objectives of this review are to describe SoJIA and emphasise the recent advances in the pathogenesis and treatment, which have transformed the care and the prognosis of this potentially life-threatening paediatric condition.

Endothelial mineralocorticoid receptor activation mediates endothelial dysfunction in diet-induced obesity.

AIMS: Aldosterone plays a crucial role in cardiovascular disease. 'Systemic' inhibition of its mineralocorticoid receptor (MR) decreases atherosclerosis by reducing inflammation and oxidative stress. Obesity, an important cardiovascular risk factor, is an inflammatory disease associated with increased plasma aldosterone levels. We have investigated the role of the 'endothelial' MR in obesity-induced endothelial dysfunction, the earliest stage in atherogenesis. METHODS AND RESULTS: C57BL/6 mice were exposed to a normal chow diet (ND) or a high-fat diet (HFD) alone or in combination with the MR antagonist eplerenone (200 mg/kg/day) for 14 weeks. Diet-induced obesity impaired endothelium-dependent relaxation in response to acetylcholine, whereas eplerenone treatment of obese mice prevented this. Expression analyses in aortic endothelial cells isolated from these mice revealed that eplerenone attenuated expression of pro-oxidative NADPH oxidase (subunits p22phox, p40phox) and increased expression of antioxidative genes (glutathione peroxidase-1, superoxide dismutase-1 and -3) in obesity. Eplerenone did not affect obesity-induced upregulation of cyclooxygenase (COX)-1 or prostacyclin synthase. Endothelial-specific MR deletion prevented endothelial dysfunction in obese (exhibiting high 'endogenous' aldosterone) and in 'exogenous' aldosterone-infused lean mice. Pre-incubation of aortic rings from aldosterone-treated animals with the COX-inhibitor indomethacin restored endothelial function. Exogenous aldosterone administration induced endothelial expression of p22phox in the presence, but not in the absence of the endothelial MR. CONCLUSION: Obesity-induced endothelial dysfunction depends on the 'endothelial' MR and is mediated by an imbalance of oxidative stress-modulating mechanisms. Therefore, MR antagonists may represent an attractive therapeutic strategy in the increasing population of obese patients to decrease vascular dysfunction and subsequent atherosclerotic complications.

Exercice physique et athérosclérose : quels sont les mécanismes physiologiques et moléculaires de l'exercice qui préviennent et protègent de l'athérosclérose? : approche chez un modèle expérimental d'athérosclérose : la souris génétiquement dépourvue en apolipoprotéine E (apoE-/-)

RESUME : L'athérosclérose, pathologie inflammatoire artérielle chronique, est à l'origine de la plupart des maladies cardiovasculaires qui constituent l'une des premières causes de morbidité et mortalité en France. Les études observationnelles et expérimentales montrent que l'exercice physique prévient la mortalité cardiovasculaire. Cependant, les mécanismes précisant les bénéfices cliniques de l'exercice sur l'athérosclérose sont encore largement inconnus. Le but général de ce travail a donc été d'explorer, en utilisant un modèle expérimental d'athérosclérose, la souris hypercholestérolémique génétiquement dépourvue en apolipoprotéine E (apoE-/-), les mécanismes athéroprotecteurs de l'exercice. La dysfonction endothéliale, généralement associée aux facteurs de risque cardiovasculaire, serait l'une des étapes précoces majeures de l'athérogenèse. Elle est caractérisée par une diminution de la biodisponibilité en monoxyde d'azote (NO) avec la perte de ses propriétés vasculo-protectrices, ce qui favorise un climat pro-athérogène (stress oxydatif, adhésion et infiltration des cellules inflammatoires dans la paroi artérielle...) conduisant à la formation de la plaque athéromateuse. L'objectif de notre premier travail a donc été d'explorer les effets de l'exercice d'une part, sur le développement des plaques athéromateuses et d'autre part, sur la fonction endothéliale de la souris apoE-/-. Nos résultats montrent que l'exercice réduit significativement l'extension de l'athérosclérose et prévient la dysfonction endothéliale. L'explication pharmacologique montre que l'exercice stimule la fonction endothéliale via, notamment, une plus grande sensibilité des récepteurs endothéliaux muscariniques, ce qui active les événements signalétiques cellulaires récepteurs-dépendants à l'origine d'une bioactivité accrue de NO. Les complications cliniques graves de l'athérosclérose sont induites par la rupture de la plaque instable provoquant la formation d'un thrombus occlusif et l'ischémie du territoire tissulaire en aval. L'objectif de notre deuxième travail a été d'examiner l'effet de l'exercice sur la qualité/stabilité de la plaque. Nos résultats indiquent que l'exercice de longue durée stabilise la plaque en augmentant le nombre de cellules musculaires lisses et en diminuant le nombre de macrophages intra-plaques. Nos résultats montrent aussi que la phosphorylation de la eNOS (NO Synthase endothéliale) Akt-dépendante n'est pas le mécanisme moléculaire majeur à l'origine de ce bénéfice. Enfin, dans notre troisième travail, nous avons investigué l'effet de l'exercice sur le développement de la plaque vulnérable. Nos résultats montrent, chez un modèle murin de plaque instable (modèle d'hypertension rénovasculaire à rénine et angiotensine II élevés) que l'exercice prévient l'apparition de la plaque vulnérable indépendamment d'un effet hémodynamique. Ce bénéfice serait associé à une diminution de l'expression vasculaire des récepteurs AT1 de l'Angiotensine II. Nos résultats justifient l'importance de l'exercice comme outil préventif des maladies cardiovasculaires. ABSTRACT : Atherosclerosis, a chronic inflammatory disease, is one of the main causes of morbidity and mortality in France. Observational and experimental data indicate that regular physical exercise has a positive impact on cardiovascular mortality. However, the mechanisms by which exercise exerts clinical benefits on atherosclerosis are still unknown. The general aim of this work was to elucidate the anti-atherosclerotic effects of exercise, using a mouse model of atherosclerosis: the apolipoprotein E-deficient mice (apoE-/- mice). Endothelial dysfunction, generally associated with cardiovascular risk factors, has been recognized to be a major and early step in atherogenesis. Endothelial dysfunction is characterized by Nitric Oxide (NO) biodisponibility reduction with loss of NO-mediated vasculoprotective actions. This leads to vascular effects such as increased oxidative stress and increased adhesion of inflammatory cells into arterial wall thus playing a role in atherosclerotic plaque development. Therefore, one of the objective of our study was to explore the effects of exercise on atherosclerotic plaque extension and on endothelial function in apoE-/- mice. Results show that exercise significantly reduces plaque progression and prevents endothelial dysfunction. Pharmacological explanation indicates that exercise stimulates endothelial function by increasing muscarinic receptors sensitivity which in turn activates intracellular signalling receptor-dependent events leading to increased NO bioactivity. The clinical manifestations of atherosclerosis are the consequences of unstable plaque rupture with thrombus formation leading to tissue ischemia. The second aim of our work was to determine the effect of exercise on plaque stability. We demonstrate that long-term exercise stabilizes atherosclerotic plaques as shown by decreased macrophage and increased Smooth Muscle Cells plaque content. Our results also suggest that the Akt-dependent eNOS phosphorylation pathway is not the primary molecular mechanism mediating these beneficial effects. Finally, we assessed a putative beneficial effect of exercise on vulnerable plaque development. In a mouse model of Angiotensine II (Ang II)-mediated vulnerable atherosclerotic plaques, we provide fist evidence that exercise prevents atherosclerosis progression and plaque vulnerability. The beneficial effect of swimming was associated with decreased aortic Ang II AT1 receptor expression independently from any hemodynamic change. These findings suggest clinical benefit of exercise in terms of cardiovascular event protection.

A new chemical tool (C0036E08) supports the role of adenosine A(2B) receptors in mediating human mast cell activation.

Asthma is a chronic inflammatory disease of the airways that involves many cell types, amongst which mast cells are known to be important. Adenosine, a potent bronchoconstricting agent, exerts its ability to modulate adenosine receptors of mast cells thereby potentiating derived mediator release, histamine being one of the first mediators to be released. The heterogeneity of sources of mast cells and the lack of highly potent ligands selective for the different adenosine receptor subtypes have been important hurdles in this area of research. In the present study we describe compound C0036E08, a novel ligand that has high affinity (pK(i) 8.46) for adenosine A(2B) receptors, being 9 times, 1412 times and 3090 times more selective for A(2B) receptors than for A(1), A(2A) and A(3) receptors, respectively. Compound C0036E08 showed antagonist activity at recombinant and native adenosine receptors, and it was able to fully block NECA-induced histamine release in freshly isolated mast cells from human bronchoalveolar fluid. C0036E08 has been shown to be a valuable tool for the identification of adenosine A(2B) receptors as the adenosine receptors responsible for the NECA-induced response in human mast cells. Considering the increasing interest of A(2B) receptors as a therapeutic target in asthma, this chemical tool might provide a base for the development of new anti-asthmatic drugs.

Xanthine oxidase inhibition by febuxostat attenuates experimental atherosclerosis in mice.

Atherosclerosis is a chronic inflammatory disease due to lipid deposition in the arterial wall. Multiple mechanisms participate in the inflammatory process, including oxidative stress. Xanthine oxidase (XO) is a major source of reactive oxygen species (ROS) and has been linked to the pathogenesis of atherosclerosis, but the underlying mechanisms remain unclear. Here, we show enhanced XO expression in macrophages in the atherosclerotic plaque and in aortic endothelial cells in ApoE(-/-) mice, and that febuxostat, a highly potent XO inhibitor, suppressed plaque formation, reduced arterial ROS levels and improved endothelial dysfunction in ApoE(-/-) mice without affecting plasma cholesterol levels. In vitro, febuxostat inhibited cholesterol crystal-induced ROS formation and inflammatory cytokine release in murine macrophages. These results demonstrate that in the atherosclerotic plaque, XO-mediated ROS formation is pro-inflammatory and XO-inhibition by febuxostat is a potential therapy for atherosclerosis.

Atherosclerotic mice exhibit systemic inflammation in periadventitial and visceral adipose tissue, liver, and pancreatic islets.

OBJECTIVE: Atherosclerosis is a chronic inflammatory disease of major conduit arteries. Similarly, obesity and type 2 diabetes mellitus are associated with accumulation of macrophages in visceral white adipose tissue and pancreatic islets. Our goal was to characterize systemic inflammation in atherosclerosis with hypercholesterolemia, but without obesity. METHODS AND RESULTS: We compared 22-week-old apolipoprotein E knockout (ApoE(-/-)) with wild-type mice kept for 14 weeks on a high cholesterol (1.25%) diet (CD, n=8) and 8-week-old ApoE(-/-) with wild-type mice kept on a normal diet (ND, n=8). Hypercholesterolemic, atherosclerotic ApoE(-/-) mice on CD exhibited increased macrophages and T-cells in plaques and periadventitial adipose tissue that revealed elevated expression of MIP-1alpha, IL-1beta, IL-1 receptor, and IL-6. Mesenteric adipose tissue and pancreatic islets in ApoE(-/-) mice showed increased macrophages. Expression of IL-1beta was enhanced in mesenteric adipose tissue of ApoE(-/-) mice on CD. Furthermore, these mice exhibited steatohepatitis with macrophage and T-cell infiltrations as well as increased MIP-1alpha and IL-1 receptor expression. Blood glucose, insulin and total body weight did not differ between the groups. CONCLUSIONS: In hypercholesterolemic lean ApoE(-/-) mice, inflammation extends beyond atherosclerotic plaques to the periadventitial and visceral adipose tissue, liver, and pancreatic islets without affecting glucose homeostasis.