Myeloid expression of the anti-apoptotic protein Mcl1 is required in anti-myeloperoxidase vasculitis but myeloperoxidase inhibition is not protective.

Antibodies to neutrophil and monocyte myeloperoxidase and proteinase 3 are a feature of anti-neutrophil cytoplasmic antibody vasculitis, a disease with significant morbidity for which new treatments are needed. Mice with a myeloid-specific deletion of the anti-apoptotic protein Mcl1 have reduced numbers of circulating neutrophils. Here, we assessed if myeloid-specific Mcl1 was required in murine anti-myeloperoxidase vasculitis and whether inhibition of myeloperoxidase was protective. In a murine model of anti-neutrophil cytoplasmic antibody vasculitis, induced by anti-myeloperoxidase antibody, mice with a myeloid-specific deletion of Mcl1 were protected from disease. They had fewer crescents, neutrophils, and macrophages in the glomeruli, lower serum creatinine levels and reduced albuminuria compared with controls. At baseline and day six after disease induction they had fewer circulating neutrophils than controls. At day six there were also fewer circulating monocytes. Myeloperoxidase inhibition with AZD5904 had no effect on histological or biochemical parameters of disease, and there was also no reduction in albuminuria at day one, two, five or seven after disease induction. These findings persisted when disease was induced without granulocyte-colony stimulating factor, which increases disease severity. A second myeloperoxidase inhibitor, AZM198, also showed no evidence of an effect, although both AZD5904 and AZM198 inhibited human neutrophil extracellular trap formation in vitro. Thus, our results show that while myeloid-specific Mcl1 is required in this model of anti-myeloperoxidase vasculitis, myeloperoxidase inhibition is not protective.

Recombinant Human Soluble Thrombomodulin Suppresses Arteritis in a Mouse Model of Kawasaki Disease.

INTRODUCTION AND OBJECTIVE: Kawasaki disease (KD) is associated with diffuse and systemic vasculitis of unknown aetiology and primarily affects infants and children. Intravenous immunoglobulin (IVIG) treatment reduces the risk of developing coronary aneurysms, but some children have IVIG-resistant KD, which increases their risk of developing coronary artery injury. Here, we investigated the effect of recombinant human soluble thrombomodulin (rTM), which has anticoagulant, anti-inflammatory, and cytoprotective properties on the development of coronary arteritis in a mouse model of vasculitis. METHODS: An animal model of KD-like vasculitis was created by injecting mice with Candida albicans water-soluble fraction (CAWS). This model was used to investigate the mRNA expression of interleukin (IL)-10, tumour necrosis factor alpha (TNF-α), and tissue factor (TF), in addition to histopathology of heart tissues. RESULTS: rTM treatment significantly reduces cardiac vascular endothelium hypertrophy by 34 days after CAWS treatment. In addition, mRNA expression analysis revealed that rTM administration increased cardiac IL-10 expression until day 27, whereas expression of TNF-α was unaffected. Moreover, in the spleen, rTM treatment restores IL-10 and TF expression to normal levels. CONCLUSION: These findings suggest that rTM suppresses CAWS-induced vasculitis by upregulating IL-10. Therefore, rTM may be an effective treatment for KD.

Human umbilical cord mesenchymal stem cells regulate CD54 and CD105 in vascular endothelial cells and suppress inflammation in Kawasaki disease.

OBJECTIVE: The objective was to evaluate the expression levels of CD31+CD54+ and CD31+CD105+ endothelial microparticles (EMPs) before and after intravenous immunoglobulin (IVIG) treatment of Kawasaki disease (KD). To explore the role of human umbilical cord mesenchymal stem cells (hucMSCs) in inhibiting endothelial inflammation in KD, the effects of hucMSCs on the expression of CD54 and CD105 in endothelial cells in KD were analyzed in vivo and in vitro. METHODS: The concentrations of IL-1ß and VEGF in the peripheral blood of KD or healthy children were detected, and the distributions of CD31+CD54+ and CD31+CD105+ EMPs in platelet-poor plasma (PPP) were analyzed by flow cytometry. Human umbilical vein endothelial cells (HUVECs) were first cocultured with the patients' peripheral blood mononuclear cells (PBMCs). Next, HUVECs were cocultured with hucMSCs after stimulation with inactivated serum from patients. Cell proliferation and migration activities were assessed, and the expression of CD54, CD105 and IL-1ß was analyzed. In an in vivo study, hucMSCs were transplanted into KD mice. The locations and expression levels of CD54, CD105 and IL-1ß in the heart tissues of mice were analyzed. RESULTS: The levels of IL-1ß and CD31+CD54+ EMPs were significantly higher before IVIG treatment and 2 weeks after treatment in KD patients (P < 0.01). However, the levels of VEGF and CD31+CD105+ EMPs increased significantly in KD only after IVIG treatment (P < 0.01). KD-inactivated serum stimulation combined with cocultivation of PBMCs can activate inflammation in HUVECs, leading to reduced cell proliferation and migration activities. Cocultivation also increased the expression of CD54 and decreased the expression of CD105 (P < 0.001). Cocultivation with hucMSCs can reverse these changes. Additionally, hucMSC transplantation downregulated the expression of IL-1ß and CD54 and significantly upregulated the expression of CD105 in KD mice. CONCLUSION: The expression levels of CD31+CD54+ and CD31+CD105+ EMPs showed inconsistent changes at different KD statuses, providing potential markers for clinical application. HucMSCs suppress inflammation and regulate the expression levels of CD54 and CD105 in vascular endothelial cells in KD, possibly providing a new basis for stem cell therapy for KD.

G-CSF and G-CSF-related vasculitis: a systematic review of the literature and intriguing future research perspectives.

Background: There are several case reports suggesting that G-CSFs may, in rare conditions, produce serious side effects, such as vasculitis. Materials & methods: A systematic search was conducted in Medline via PubMed, Embase and Cochrane Library to describe this unusual side effect to raise awareness among clinicians for early recognition and treatment. Results: Fifty-seven patients were analyzed. The most prevalent cancer type was breast cancer (47%). Long-acting G-CSF was used in 38 patients (67%). Only 47% of patients were treated with steroids. Conclusion: Although the benefit of G-CSF treatment outweighs the potential damage, oncologists should consider the possibility of triggering a vascular toxicity and try to identify patients at increased risk for this side effect.

Lay abstract Background: Several case reports suggest that a type of drug called granulocyte colony-stimulating factor (G-CSFs) may, in rare cases, produce serious side effects, such as vasculitis. Materials & methods: A systematic search was conducted to describe this unusual side effect. Results: Fifty-seven patients were analyzed. The most prevalent cancer type in which this side effect was observed was breast cancer (47%). Only 47% of patients were treated with steroids. The main symptoms, such as fever, chest/epigastric pain and general malaise, are nonspecific and cannot be used to diagnose the side effect; laboratory findings are suggestive of inflammation. Conclusion: Accurate assessment of what causes this adverse event is extremely important. Although the benefit of G-CSF treatment outweighs the potential damage, oncologists should consider the possibility of triggering vascular toxicity and try to identify patients at increased risk.

2021 American College of Rheumatology/Vasculitis Foundation guideline for the management of antineutrophil cytoplasmic antibody-associated vasculitis

To provide evidence-based recommendations and expert guidance for the management of antineutrophil cytoplasmic antibody-associated vasculitis (AAV), including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Clinical questions regarding the treatment and management of AAV were developed in the population, intervention, comparator, and outcome (PICO) format (47 for GPA/MPA, 34 for EGPA). Systematic literature reviews were conducted for each PICO question. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of evidence and formulate recommendations. Each recommendation required ≥70% consensus among the Voting Panel. We present 26 recommendations and 5 ungraded position statements for GPA/MPA, and 15 recommendations and 5 ungraded position statements for EGPA. This guideline provides recommendations for remission induction and maintenance therapy as well as adjunctive treatment strategies in GPA, MPA, and EGPA. These recommendations include the use of rituximab for remission induction and maintenance in severe GPA and MPA and the use of mepolizumab in nonsevere EGPA. All recommendations are conditional due in part to the lack of multiple randomized controlled trials and/or low-quality evidence supporting the recommendations. This guideline presents the first recommendations endorsed by the American College of Rheumatology and the Vasculitis Foundation for the management of AAV and provides guidance to health care professionals on how to treat these diseases.

Rheumatologic manifestations of Hepatitis C Virus.

INTRODUCTION: Hepatitis C Virus (HCV) is a well-known worldwide infection, responsible for hepatic and extrahepatic complications. Among extrahepatic manifestation, the rheumatologic are the most common ones. With the arrival of Direct Antiviral Agents (DAA), the treatment and the clinical perspective have rapidly changed, permitting to achieve a sustained virological response (SVR) and preventing complications of chronic infection. EVIDENCE ACQUISITION: We performed on PubMed a literature search for the articles published by using the search terms "HCV infection," "HCV syndrome," "HCV-related rheumatologic disorders," "cryoglobulinemia," "cryoglobulinemic vasculitis" and "mixed cryoglobulinemia." EVIDENCE SYNTHESIS: Mixed cryoglobulinemia (MC) is the prototype of HCV-associated rheumatologic disorder. HCV-related MC is typically considered by physicians as a human model disease to linking infection with autoimmune diseases. Chronic HCV infection can lead to a multistep process from a simple serological alteration (presence of circulating serum cryoglobulins) to frank systemic vasculitis (cryoglobulinemic vasculitis [CV]) and ultimately to overt malignant B lymphoproliferation (such as non-Hodgkin lymphoma [NHL]). Antiviral therapy is indicated to eradicate the HCV infection and to prevent the complications of chronic infection. Immunosuppressive therapy is reserved in case of organ threatening manifestations of CV. In this review, we discuss the main clinical presentation, diagnostic approach and treatment of rheumatologic manifestations of HCV infection. CONCLUSIONS: Chronic HCV infection is responsible for complex clinical condition, ranging from hepatic to extra-hepatic disorders. Cryoglobulins are the result of this prolonged immune system stimulation, caused by tropism of HCV for B-lymphocyte.

Preventive effect of cocoa flavanols against glucotoxicity-induced vascular inflammation in the arteria of diabetic rats and on the inflammatory process in TNF-α-stimulated endothelial cells.

Hyperglycaemia induces a vascular inflammatory process that is a critical event in cardiovascular disease in type 2 diabetes. Cocoa and its flavanols have been widely investigated for its antioxidant and anti-inflammatory properties, and several clinical and pre-clinical studies support their vascular benefits. However, the effects of cocoa flavanols on vascular inflammation in diabetes remains to be elucidated. Herein, we evaluated the anti-inflammatory effect of a cocoa-rich diet on the aortas of Zucker diabetic fatty (ZDF) rats. Moreover, the potential role of flavanol-derived colonic metabolites to modulate the adhesion and inflammatory processes were also evaluated using TNF-α-stimulated endothelial cells. Results demonstrate that cocoa attenuates the levels of phospho-p65-nuclear factor-kappaB (NF-κB) and the expression of inflammatory factors including intercellular adhesion molecule-1 (ICAM-1), vascular adhesion molecule-1 (VCAM-1) and inducible nitric oxide synthase in the aortas of ZDF rats. Experiments with endothelial cells further confirm that a mix of flavanol-derived colonic metabolites effectively down-regulate the levels of p-p65-NF-κB and the cell adhesion molecules ICAM-1 and VCAM-1, preventing thus the increase of monocyte-endothelial adhesion induced by TNF-α. These novel data provide the first evidence of the relevant role of cocoa and their flavanol-derived metabolites to avoid the development of endothelial inflammation and diabetic complications.

Zanthoxylum nitidum extract attenuates BMP-2-induced inflammation and hyperpermeability.

Bone morphogenetic protein-2 (BMP-2) is commonly applied in spinal surgery to augment spinal fusion. Nevertheless, its pro-inflammatory potential could induce dangerous side effects such as vascular hyper-permeability, posing the need for manners against this condition. The present study aims to investigate the protective effect of Zanthoxylum nitidum (ZN) on BMP-2-related hyperpermeability and inflammation on the human umbilical vein endothelial cells (HUVECs). The results revealed that, in a concentration-dependent manner, BMP-2 enhanced the production of pro-inflammatory cytokines, including interleukin (IL)-1α, IL-1ß, and tumor necrosis factor-α, which were, however, suppressed by ZN. ZN inhibited BMP-2-induced inflammatory response by suppressing the phosphorylation of NF-κBp65 and IκB, and the abnormal nuclear translocation of p65. Moreover, the inhibited expression intercellular tight junction protein VE-cadherin and Occludin caused by BMP-2 was blocked by ZN. The hyper-permeability of HUVECs induced by BMP-2, as expressed as the higher fluorescent intensity of dextran, was also reversed by ZN. Overall, these findings demonstrated that ZN antagonized BMP-2-induced inflammation and hyperpermeability. It could be a therapeutic candidate for the treatment of BMP-2-induced side effects during spinal fusion.

Novel Role for Tranilast in Regulating NLRP3 Ubiquitination, Vascular Inflammation, and Atherosclerosis.

Background Aberrant activation of the NLRP3 (nucleotide-binding oligomerization domain, leucine-rich repeat-containing receptor family pyrin domain-containing 3) inflammasome is thought to play a causative role in atherosclerosis. NLRP3 is kept in an inactive ubiquitinated state to avoid unwanted NLRP3 inflammasome activation. This study aimed to test the hypothesis that pharmacologic manipulating of NLRP3 ubiquitination blunts the assembly and activation of the NLRP3 inflammasome and protects against vascular inflammation and atherosclerosis. Since genetic studies yielded mixed results about the role for this inflammasome in atherosclerosis in low-density lipoprotein receptor- or apolipoprotein E-deficient mice, this study attempted to clarify the discrepancy with the pharmacologic approach using both models. Methods and Results We provided the first evidence demonstrating that tranilast facilitates NLRP3 ubiquitination. We showed that tranilast restricted NLRP3 oligomerization and inhibited NLRP3 inflammasome assembly. Tranilast markedly suppressed NLRP3 inflammasome activation in low-density lipoprotein receptor- and apolipoprotein E-deficient macrophages. Through reconstitution of the NLRP3 inflammasome in human embryonic kidney 293T cells, we found that tranilast directly limited NLRP3 inflammasome activation. By adopting different regimens for tranilast treatment of low-density lipoprotein receptor- and apolipoprotein E-deficient mice, we demonstrated that tranilast blunted the initiation and progression of atherosclerosis. Mice receiving tranilast displayed a significant reduction in atherosclerotic lesion size, concomitant with a pronounced decline in macrophage content and expression of inflammatory molecules in the plaques compared with the control group. Moreover, tranilast treatment of mice substantially hindered the expression and activation of the NLRP3 inflammasome in the atherosclerotic lesions. Conclusions Tranilast potently enhances NLRP3 ubiquitination, blunts the assembly and activation of the NLRP3 inflammasome, and ameliorates vascular inflammation and atherosclerosis in both low-density lipoprotein receptor- and apolipoprotein E-deficient mice.

Cav-1 (Caveolin-1) Deficiency Increases Autophagy in the Endothelium and Attenuates Vascular Inflammation and Atherosclerosis.

OBJECTIVE: Endothelial Cav-1 (caveolin-1) expression plays a relevant role during atherogenesis by controlling NO production, vascular inflammation, LDL (low-density lipoprotein) transcytosis, and extracellular matrix remodeling. Additional studies have identified cholesterol-rich membrane domains as important regulators of autophagy by recruiting ATGs (autophagy-related proteins) to the plasma membrane. Here, we investigate how the expression of Cav-1 in the aortic endothelium influences autophagy and whether enhanced autophagy contributes to the atheroprotective phenotype observed in Cav-1-deficient mice. Approach and Results: To analyze the impact of Cav-1 deficiency on regulation of autophagy in the aortic endothelium during the progression of atherosclerosis, we fed Ldlr-/- and Cav-1-/-Ldlr-/- mice a Western diet and assessed autophagy in the vasculature. We observe that the absence of Cav-1 promotes autophagy activation in athero-prone areas of the aortic endothelium by enhancing autophagic flux. Mechanistically, we found that Cav-1 interacts with the ATG5-ATG12 complex and influences the cellular localization of autophagosome components in lipid rafts, which controls the autophagosome formation and autophagic flux. Pharmacological inhibition of autophagy attenuates the atheroprotection observed in Cav-1-/- mice by increasing endothelial inflammation and macrophage recruitment, identifying a novel molecular mechanism by which Cav-1 deficiency protects against the progression of atherosclerosis. CONCLUSIONS: These results identify Cav-1 as a relevant regulator of autophagy in the aortic endothelium and demonstrate that pharmacological suppression of autophagic flux in Cav-1-deficient mice attenuates the atheroprotection observed in Cav-1-/- mice. Additionally, these findings suggest that activation of endothelial autophagy by blocking Cav-1 might provide a potential therapeutic strategy for cardiovascular diseases including atherosclerosis.

Myriocin and d-PDMP ameliorate atherosclerosis in ApoE-/- mice via reducing lipid uptake and vascular inflammation.

Sphingolipids have been implicated in the etiology of atherosclerosis. The commonly used sphingolipid inhibitors, myriocin (a ceramide inhibitor) and d-PDMP (d-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol, a glycosphingolipid inhibitor), have shown therapeutic potential but their efficacy and their underlying mechanisms remain unclear. Here, apolipoprotein E-deficient (apoE-/-) mice were fed a high-fat diet (HFD) and treated with a control, myriocin, d-PDMP, or atorvastatin for 12 weeks. We analyzed the effects of these drugs on the size and detailed composition of atherosclerotic plaques. Molecular biological approaches were used to explore how the inhibitors affect lipid metabolism and foam-cell formation. Treatment with myriocin or d-PDMP led to smaller and less vulnerable atherosclerotic lesions and was almost as effective as atorvastatin. Sphingolipid inhibitors down-regulated the expression of monocyte chemotactic protein 1 (MCP-1) and its receptor chemoattractant cytokine receptor 2 (CCR2), which play a key role in monocyte recruitment. They also decreased pro-inflammatory Ly-6chigh monocytes and influenced the uptake of modified LDL by down-regulating the expression of cluster of differentiation 36 (CD36) and lectin-like oxidized LDL (ox-LDL) receptor-1 (LOX-1). The inhibitors exhibited the advantage of maintaining normal glucose homeostasis compared with atorvastatin. These findings reveal for the first time that the modulation of sphingolipid synthesis can effectively alleviate atherosclerosis progression by preventing lipid uptake and reducing inflammatory responses in the arterial walls.

A Comprehensive Update on Kawasaki Disease Vasculitis and Myocarditis.

PURPOSE OF THE REVIEW: Kawasaki disease (KD) is a childhood systemic vasculitis of unknown etiology that causes coronary artery aneurysms (CAA), and if left undiagnosed can result in long-term cardiovascular complications and adult cardiac disease. Up to 20% of KD children fail to respond to IVIG, the mainstay of therapy, highlighting the need for novel therapeutic strategies. Here we review the latest findings in the field regarding specific etiology, genetic associations, and advancements in treatment strategies to prevent coronary aneurysms. RECENT FINDINGS: Recent discoveries using the Lactobacillus casei cell wall extract (LCWE)-induced KD vasculitis mouse model have accelerated the study of KD pathophysiology and have advanced treatment strategies including clinical trials for IL-1R antagonist, Anakinra. KD remains an elusive pediatric vasculitis syndrome and is the leading cause of acquired heart disease among children in the USA and developed countries. Advancements in combination treatment for refractory KD with further understanding of novel genetic risk factors serve as a solid foundation for future research endeavors in the field.

Combination of curcumin and luteolin synergistically inhibits TNF-α-induced vascular inflammation in human vascular cells and mice.

Emerging evidence shows that phytochemicals, the secondary plant metabolites present in a large variety of foods, have the potential ability in reducing the risk of cardiovascular diseases. However, the dosages of phytochemicals in the cellular and animal studies are too high to reach in humans by relevant foods or dietary supplement intake. The aims of this study were to investigate whether and how combined curcumin and luteolin synergistically inhibit tumor necrosis factor-alpha (TNF-α)-induced monocytes adhesion endothelium, a crucial step of the development of endothelial dysfunction, both in human vascular cells and mouse aortic endothelium. Our results show that combined curcumin (1 µM) and luteolin (0.5 µM) synergistically (combination index is 0.60) inhibited TNF-α-induced monocytes adhesion to human EA.hy926 endothelial cells while the individual chemicals did not have such effect at the selected concentrations. We also found that TNF-α-enhanced protein expressions of vascular cell adhesion molecule 1 (VCAM-1), monocyte chemotactic protein-1 (MCP-1) and nuclear factor (NF)-κB translocation were synergistically reduced by the combined curcumin and luteolin in EA.hy 926 cells while the individual chemical did not have this inhibitory effect. Consistently, 2 weeks dietary intake of combined curcumin (500 mg/kg) and luteolin (500 mg/kg) in C57BL/6 mice synergistically prevented TNF-α-stimulated adhesion of mouse monocytes to aortic endothelium ex vivo as well as the TNF-α-increased aortic protein expression of MCP-1 and VCAM-1. Therefore, combined curcumin and luteolin at physiological concentrations synergistically inhibits TNF-α-induced monocytes adhesion to endothelial cells and expressions of MCP-1 and VCAM-1 via suppressing NF-κB translocation into the nucleus.

Prevention of Vascular Inflammation by Pterostilbene via Trimethylamine-N-Oxide Reduction and Mechanism of Microbiota Regulation.

SCOPE: A gut-microbiota-dependent metabolite of L-carnitine, trimethylamine-N-oxide (TMAO), has been recently discovered as an independent and dose-dependent risk factor for cardiovascular disease (CVD). This study aims to investigate the effects of pterostilbene on reducing TMAO formation and on decreasing vascular inflammation in carnitine-feeding mice. METHODS AND RESULTS: C57BL/6 mice are treated with 1.3% carnitine in drinking water with or without pterostilbene supplementation. Using LC-MS/MS, the result shows that mice treated with 1.3% carnitine only significantly increased the plasma TMAO and pterostilbene supplementation group can reverse it. Additionally, pterostilbene decreases hepatic flavin monooxygenase 3 (FMO3) mRNA levels compared to carnitine only group. It appears that pterostilbene can alter host physiology and create an intestinal microenvironment favorable for certain gut microbiota. Gut microbiota analysis reveals that pterostilbene increases the abundance of Bacteroides. Further, pterostilbene decreases mRNA levels of vascular inflammatory markers tumor necrosis factor-α (TNF-α), vascular cell adhesion molecule 1 (VCAM-1), and E-selectin). CONCLUSION: These data suggest that amelioration of carnitine-induced vascular inflammation after consumption of pterostilbene is partially mediated via modulation of gut microbiota composition and hepatic enzyme FMO3 gene expression.

Poldip2 deficiency protects against lung edema and vascular inflammation in a model of acute respiratory distress syndrome.

Acute respiratory distress syndrome (ARDS) in a deadly disease that can be brought on by endotoxins such as lipopolysaccharide (LPS). ARDS is characterized by vascular permeability, a severe inflammatory response, lung leukocyte infiltration, and resultant lung edema. Polymerase δ-interacting protein 2 (Poldip2) is a novel regulator of blood-brain barrier permeability; however, its role in regulating lung permeability and vascular inflammation is unknown. Here, the role of Poldip2 in regulating vascular permeability and inflammation in a mouse model of ARDS was assessed. Heterozygous deletion of Poldip2 was found to reduce LPS-induced mortality within 20 h, lung inflammatory signaling, and leukocyte infiltration. Moreover, reduced Poldip2-suppressed LP-induced vascular cell adhesion molecule (VCAM)-1 induction, leukocyte recruitment, and mitochondrial reactive oxygen species (ROS) production in vitro These data indicate that Poldip2 is an important regulator of the debilitating consequences of ARDS, potentially through the regulation of mitochondrial ROS-induced inflammatory signaling. Consequently, inhibition of Poldip2 may be a viable option for therapeutic discovery moving forward.

Blockage of macrophage migration inhibitory factor (MIF) suppressed uric acid-induced vascular inflammation, smooth muscle cell de-differentiation, and remodeling.

Hyperuricemia contributes to vascular injury and dysfunction, yet the potential mechanisms are not well understood. Uric acid (UA) has been found to stimulate macrophage migration inhibitory factor (MIF) up-regulation in renal tubules from rats subjected to UA-induced nephropathy. Given that MIF is able to induce vascular smooth muscle cell (VSMC) de-differentiation (from contractile state to a secretory state), we thus hypothesized that UA-induced vascular injury is via up-regulating of MIF in VSMCs, which enhancing vascular inflammation and VSMC transition. Within a mouse model of UA injection (500 mg/kg, twice/day, 14 days), we measured circulating and vascular MIF levels under UA stimulation at 6 h, day 1, and 14. We tested the efficacy of MIF inhibitor (10 mg/kg, twice/day, 14 days) on UA-induced vascular inflammation and remodeling. High plasma level of UA induced vascular MIF release into the plasma at acute phase. In the chronic phase, the protein level of MIF is up-regulated in the vessels. MIF inhibitor suppressed vascular inflammatory responses, repressed VSMC de-differentiation, and attenuated vascular remodeling and dysfunction following UA stimulation. Knockdown of MIF in cultured VSMCs repressed UA-induced de-differentiation. Our results provided a novel mechanism for MIF-mediated vascular injury in response to UA stimulation, and suggested that anti-MIF interventions may be of therapeutic value in hyperuricemic patients.

Successful use of rituximab in granulomatosis with polyangiitis with aortic inflammation.

Large-vessel inflammation, although rare, has been increasingly recognised as a complication of granulomatosis with polyangiitis (GPA) in recent years. The presentation is highly variable, ranging from an incidental finding to aortic dissection and rupture. Treatment has predominately consisted of a combination of cyclophosphamide and high dose corticosteroids with surgical intervention when indicated. We present the case of a 34-year-old male diagnosed with GPA after presenting with sinus and eye inflammation and the ensuing investigation revealed large vessel involvement that remarkably improved after 6 months of treatment with the combination of rituximab infusions, methotrexate and corticosteroids.

Germinated Brown Rice Attenuates Atherosclerosis and Vascular Inflammation in Low-Density Lipoprotein Receptor-Knockout Mice.

The present study investigates the impact of germinated brown rice (GBR) on atherosclerosis and the underlying mechanism in low-density lipoprotein receptor-knockout (LDLr-KO) mice. The intensity of atherosclerosis in aortas of LDLr-KO mice receiving diet supplemented with 60% GBR (weight/weight) was significantly less than that in mice fed with 60% white rice (WR) or control diet ( p < 0.05); all diets contained 0.06% cholesterol. WR or GBR diet did not significantly alter plasma total or LDL-cholesterol, fecal sterols, or glucose, or the activities of antioxidant enzymes, compared to the control diet. The adhesion of monocytes to aortas from LDLr-KO mice fed with WR diet was significantly more than that from mice receiving the control diet ( p < 0.01). GBR diet decreased monocyte adhesion to aortas compared to WR diet ( p < 0.01). GBR diet also reduced the levels of plasminogen activator inhibitor-1 (PAI-1), monocyte chemotactic protein-1 (MCP-1), and tumor necrosis factor-α (TNF-α) in plasma, and the abundances of MCP-1, PAI-1, TNF-α, intracellular cell adhesion molecule-1, toll-like receptor-4, PAI-1, LDLr-like protein, and urokinase plasminogen activator and its receptor in aortas or hearts from LDLr-KO mice in comparison to the WR diet ( p < 0.05, 0.01, respectively). The findings suggest that GBR administration attenuated atherosclerosis and vascular inflammation in LDLr-KO mice compared to WR. The anti-atherosclerotic effect of GBR in LDLr-KO mice at least in part results from its anti-inflammatory activity.

Neopterin Counters Vascular Inflammation and Atherosclerosis.

BACKGROUND: Neopterin, a metabolite of GTP, is produced by activated macrophages and is abundantly expressed within atherosclerotic lesions in human aorta and carotid and coronary arteries. We aimed to clarify the influence of neopterin on both vascular inflammation and atherosclerosis, as neither effect had been fully assessed. METHODS AND RESULTS: We investigated neopterin expression in coronary artery lesions and plasma from patients with coronary artery disease. We assessed the atheroprotective effects of neopterin in vitro using human aortic endothelial cells, human monocyte-derived macrophages, and human aortic smooth muscle cells. In vivo experiments included a study of aortic lesions in apolipoprotein E-deficient mice. Neopterin expression in coronary artery lesions and plasma was markedly increased in patients with versus without coronary artery disease. In human aortic endothelial cells, neopterin reduced proliferation and TNF-α (tumor necrosis factor α)-induced upregulation of MCP-1 (monocyte chemotactic protein 1), ICAM-1 (intercellular adhesion molecule 1), and VCAM-1 (vascular cell adhesion molecule 1). Neopterin attenuated TNF-α-induced monocyte adhesion to human aortic endothelial cells and the inflammatory macrophage phenotype via NF-κB (nuclear factor-κB) downregulation. Neopterin suppressed oxidized low-density lipoprotein-induced foam cell formation associated with CD36 downregulation and upregulation of ATP-binding cassette transporters A1 and G1 in human monocyte-derived macrophages. In human aortic smooth muscle cells, neopterin suppressed angiotensin II-induced migration and proliferation via c-Src/Raf-1/ERK1/2 downregulation without inducing apoptosis. Exogenous neopterin administration and endogenous neopterin attenuation with its neutralizing antibody for 4 weeks retarded and promoted, respectively, the development of aortic atherosclerotic lesions in apolipoprotein E-deficient mice. CONCLUSIONS: Our results indicate that neopterin prevents both vascular inflammation and atherosclerosis and may be induced to counteract the progression of atherosclerotic lesions. Consequently, neopterin could be of use as a novel therapeutic target for atherosclerotic cardiovascular diseases.