Risk Stratification of Patients with Psoriatic Arthritis and Ankylosing Spondylitis for Treatment with Tofacitinib: A Review of Current Clinical Data.

In this commentary, we review clinical data which helps inform individualized benefit-risk assessment for tofacitinib in patients with psoriatic arthritis (PsA) and ankylosing spondylitis (AS). ORAL Surveillance, a safety trial of patients ≥ 50 years of age with rheumatoid arthritis (RA) and cardiovascular risk factors, found increased rates of safety outcomes (including major adverse cardiovascular events [MACE], malignancies excluding non-melanoma skin cancer, and venous thromboembolism) with tofacitinib versus tumor necrosis factor inhibitors (TNFi). Post hoc analyses of ORAL Surveillance have identified subpopulations with different relative risk versus TNFi; higher risk with tofacitinib was confined to patients ≥ 65 years of age and/or long-time current/past smokers, and specifically for MACE, patients with a history of atherosclerotic cardiovascular disease (ASCVD). In patients without these risk factors, risk differences between tofacitinib and TNFi could not be detected. Given differences in demographics, pathophysiology, and comorbidities, we sought to examine whether the risk stratification observed in RA is also appropriate for PsA and AS. Data from the PsA tofacitinib development program show low absolute risk of safety outcomes in patients < 65 years of age and never smokers, and low MACE risk in patients with no history of ASCVD, consistent with results from ORAL Surveillance. No MACE, malignancies, or venous thromboembolism were reported in the tofacitinib AS development program. The mechanism of the ORAL Surveillance safety findings is unknown, and there are no similar prospective studies of sufficient size and duration. Accordingly, it is appropriate to use a precautionary approach and extrapolate differentiating risk factors identified from ORAL Surveillance (age ≥ 65 years, long-time current/past smoking, and history of ASCVD) to PsA and AS. We recommend an individualized approach to treatment decisions based on these readily identifiable risk factors, in line with updated labeling for Janus kinase inhibitors and international guidelines for the treatment of PsA and AS.Trial Registration: NCT02092467, NCT01262118, NCT01484561, NCT00147498, NCT00413660, NCT00550446, NCT00603512, NCT00687193, NCT01164579, NCT00976599, NCT01059864, NCT01359150, NCT02147587, NCT00960440, NCT00847613, NCT00814307, NCT00856544, NCT00853385, NCT01039688, NCT02281552, NCT02187055, NCT02831855, NCT00413699, NCT00661661, NCT01877668, NCT01882439, NCT01976364, NCT00678210, NCT01710046, NCT01241591, NCT01186744, NCT01276639, NCT01309737, NCT01163253, NCT01786668, NCT03502616.

Risk of extended major adverse cardiovascular event endpoints with tofacitinib versus TNF inhibitors in patients with rheumatoid arthritis: a post hoc analysis of a phase 3b/4 randomised safety study.

OBJECTIVES: Compare the risk of extended major adverse cardiovascular (CV) event (MACE) composite outcomes and component events in patients with rheumatoid arthritis (RA) treated with tofacitinib versus tumour necrosis factor inhibitors (TNFi) in Oral Rheumatoid Arthritis Trial (ORAL) Surveillance. METHODS: Patients with RA aged ≥50 years and with ≥1 additional CV risk factor received tofacitinib 5 mg or 10 mg two times per day or TNFi. MACE (non-fatal myocardial infarction (MI), non-fatal stroke or CV death (MACE-3)) was extended by sequential addition of CV events (hospitalisation for unstable angina (MACE-4), coronary revascularisation (MACE-5), transient ischaemic attack (MACE-6), peripheral vascular disease (MACE-7)), heart failure (HF) hospitalisation (MACE-8) and venous thromboembolism (VTE; (MACE-8 plus VTE)). HRs (tofacitinib vs TNFi) were evaluated for MACE and individual components. RESULTS: HRs for MACE-4 to MACE-8 with combined and individual tofacitinib doses versus TNFi were similar. Risk of MACE-8 plus VTE appeared similar with tofacitinib 5 mg two times per day versus TNFi (HR 1.12 (0.82 to 1.52)), but higher with tofacitinib 10 mg two times per day versus TNFi (HR 1.38 (1.02 to 1.85)). Risk of MI was higher with tofacitinib versus TNFi, but difference in risk of other individual CV events was not suggested. Across extended MACE definitions, risk appeared higher with tofacitinib versus TNFi in those with atherosclerotic CV disease or age ≥65 years. CONCLUSION: In ORAL Surveillance, risk of composite CV endpoints combining all ischaemic CV events and HF did not appear different with tofacitinib versus TNFi. The totality of CV risk was higher with tofacitinib 10 mg two times per day versus TNFi, driven by an increase in VTE. TRIAL REGISTRATION NUMBER: NCT02092467.

Identification of two tofacitinib subpopulations with different relative risk versus TNF inhibitors: an analysis of the open label, randomised controlled study ORAL Surveillance.

OBJECTIVES: Based on primary results from ORAL Surveillance, an event-driven clinical trial of risk-enriched patients, identify subpopulations with different relative risk (ie, 'high-risk' and 'low-risk') with tofacitinib versus tumour necrosis factor inhibitors (TNFi). METHODS: Patients with rheumatoid arthritis aged ≥50 years with ≥1 additional cardiovascular risk factor received tofacitinib 5 or 10 mg two times a day or TNFi. Prior analyses had identified age and smoking as risk factors of particular interest across safety outcomes. Hazard ratios (HRs) and incidence rates were evaluated by age and smoking individually and in combination. Results were validated across tofacitinib development programmes. RESULTS: 'Age ≥65 years or ever smoker' defined a group ('high-risk') with increased risk of malignancies (excluding non-melanoma skin cancer), major adverse cardiovascular events, myocardial infarction, venous thromboembolism and all-cause death with tofacitinib (combined doses) versus TNFi (HRs 1.41-5.19). In patients 'aged <65 years and never smokers' ('low-risk'), there was no detectable risk increase with tofacitinib versus TNFi (HRs ≈1.0) up to 6 years of follow-up, and absolute risk remained low and was corroborated across tofacitinib rheumatoid arthritis, psoriatic arthritis and ulcerative colitis programmes with up to 10 years of observation. CONCLUSIONS: This posthoc analysis of ORAL Surveillance identified two tofacitinib subpopulations with different relative risk versus TNFi. High risk was confined to patients defined by distinct risk factors age ≥65 years or smoking, and these differentiating risk factors accounted for the excess risk observed with tofacitinib versus TNFi. These findings can guide individualised benefit/risk assessment and clinical decision-making on treatment with tofacitinib. TRIAL REGISTRATION NUMBERS: NCT02092467, NCT01262118, NCT01484561, NCT00147498, NCT00413660, NCT00550446, NCT00603512, NCT00687193, NCT01164579, NCT00976599, NCT01059864, NCT01359150, NCT02147587, NCT00960440, NCT00847613, NCT00814307, NCT00856544, NCT00853385, NCT01039688, NCT02281552, NCT02187055, NCT02831855, NCT00413699, NCT00661661, NCT00787202, NCT01465763, NCT01458951, NCT01458574, NCT01470612, NCT01877668, NCT01882439, NCT01976364.

Association between baseline cardiovascular risk and incidence rates of major adverse cardiovascular events and malignancies in patients with psoriatic arthritis and psoriasis receiving tofacitinib.

Background: Tofacitinib is a Janus kinase inhibitor for the treatment of psoriatic arthritis (PsA) and has been investigated for psoriasis (PsO). Objectives: This post hoc analysis examined baseline cardiovascular (CV) disease risk and its association with the occurrence of major adverse cardiovascular events (MACE) and malignancies in tofacitinib-treated patients with PsA and PsO. Design: Included three phase III/long-term extension (LTE) PsA trials and seven phase II/phase III/LTE PsO trials of patients receiving ⩾ 1 dose of tofacitinib. Methods: Incidence rates (IRs: patients with events/100 patient-years) for MACE and malignancies (excluding non-melanoma skin cancer) were determined in subgroups according to history of atherosclerotic CV disease (ASCVD), baseline 10-year risk of ASCVD (in patients without history of ASCVD), and baseline metabolic syndrome (MetS). Results: For patients with PsA (N = 783) and PsO (N = 3663), respectively, tofacitinib exposure was 2038 and 8950 patient-years (median duration: 3.0 and 2.4 years), and 40.9% and 32.7% had MetS. Excluding missing CV risk profile data, 51/773 (6.6%) and 144/3629 (4.0%) patients had history of ASCVD, and in patients without history of ASCVD, around 20.0% had intermediate/high baseline 10-year ASCVD risk. For PsA and PsO, IRs of MACE were greatest in those with history of ASCVD or high baseline 10-year ASCVD risk. For PsA, five of six patients with MACE had baseline MetS. Malignancy IRs in patients with PsA were greatest in those with intermediate/high baseline 10-year ASCVD risk. Of these, eight of nine patients with malignancies had baseline MetS. In the PsO cohort, IR of malignancies was notably greater with high versus low/borderline/intermediate baseline 10-year ASCVD risk. Conclusion: In tofacitinib-treated patients with PsA/PsO, increased ASCVD risk and baseline MetS were associated with higher IRs for MACE and malignancies. Our results support assessing CV risk in patients with PsA/PsO and suggest enhanced cancer monitoring in those with increased ASCVD risk. Registration ClinicalTrialsgov: NCT01877668/NCT01882439/NCT01976364/NCT00678210/NCT01710046/NCT01241591/NCT01186744/NCT01276639/NCT01309737/NCT01163253. Plain Language Summary: People who have psoriatic arthritis or psoriasis may have more heart-related problems and cancer if they have a higher risk of cardiovascular disease: A study in people with psoriatic arthritis or psoriasis receiving tofacitinib Why was this study done? • People with psoriatic arthritis (PsA) and psoriasis (PsO) are more likely than the general population to have a disease affecting the heart and blood vessels [cardiovascular (CV) disease].• People who are more likely to have CV disease may also be more likely to have certain types of cancer.• Tofacitinib is a medicine to treat people with PsA and has been tested in people with PsO.• We wanted to know if the risk of CV disease affects the number of heart-related problems (including heart attack, stroke, or death) and cancer in people with PsA and PsO. What did the researchers do? • We used results from 10 clinical trials.• In these trials, people with PsA and PsO were taking tofacitinib 5 or 10 mg twice a day.• After the trials had ended, we measured people's risk of CV disease using a risk calculator. This risk calculator showed if they had a low, borderline, intermediate, or high risk of CV disease over the next 10 years. We also checked if they had had CV disease before treatment.• We checked if people had a group of conditions linked to CV disease: diabetes, high blood pressure, and obesity.• We counted the cases of heart-related problems and cancer in people once they started taking tofacitinib. What did the researchers find? In people with PsA and PsO taking tofacitinib:• There were more cases of heart-related problems and cancer in people who had intermediate or high risk of CV disease.• There were more cases of heart-related problems in people who had had CV disease before.• More people with diabetes, high blood pressure, and obesity had heart-related problems and cancer than people without those conditions. What do the findings mean? • It is important to measure risk and assess history of CV disease in people with PsA and PsO, including those taking tofacitinib.• We should test for cancer in people with high risk of CV disease.

Risk of major adverse cardiovascular events with tofacitinib versus tumour necrosis factor inhibitors in patients with rheumatoid arthritis with or without a history of atherosclerotic cardiovascular disease: a post hoc analysis from ORAL Surveillance.

OBJECTIVES: Evaluate risk of major adverse cardiovascular events (MACE) with tofacitinib versus tumour necrosis factor inhibitors (TNFi) in patients with rheumatoid arthritis (RA) with or without a history of atherosclerotic cardiovascular disease (ASCVD) in ORAL Surveillance. METHODS: Patients with RA aged ≥50 years with ≥1 additional CV risk factor received tofacitinib 5 mg or 10 mg two times per day or TNFi. Hazard rations (HRs) were evaluated for the overall population and by history of ASCVD (exploratory analysis). RESULTS: Risk of MACE, myocardial infarction and sudden cardiac death were increased with tofacitinib versus TNFi in ORAL Surveillance. In patients with history of ASCVD (14.7%; 640/4362), MACE incidence was higher with tofacitinib 5 mg two times per day (8.3%; 17/204) and 10 mg two times per day (7.7%; 17/222) versus TNFi (4.2%; 9/214). HR (combined tofacitinib doses vs TNFi) was 1.98 (95% confidence interval (CI) 0.95 to 4.14; interaction p values: 0.196 (for HR)/0.059 (for incidence rate difference)). In patients without history of ASCVD, MACE HRs for tofacitinib 5 mg two times per day (2.4%; 30/1251) and 10 mg two times per day (2.8%; 34/1234) versus TNFi (2.3%; 28/1237) were, respectively, 1.03 (0.62 to 1.73) and 1.25 (0.76 to 2.07). CONCLUSIONS: This post hoc analysis observed higher MACE risk with tofacitinib versus TNFi in patients with RA and history of ASCVD. Among patients without history of ASCVD, all with prevalent CV risk factors, MACE risk did not appear different with tofacitinib 5 mg two times per day versus TNFi. Due to the exploratory nature of this analysis and low statistical power, we cannot exclude differential MACE risk for tofacitinib 5 mg two times per day versus TNFi among patients without history of ASCVD, but any absolute risk excess is likely low. TRIAL REGISTRATION NUMBER: NCT02092467.

Influenza Adverse Events in Patients with Rheumatoid Arthritis, Ulcerative Colitis, or Psoriatic Arthritis in the Tofacitinib Clinical Development Programs.

INTRODUCTION: This post hoc analysis evaluated influenza adverse events (AEs) across rheumatoid arthritis (RA), ulcerative colitis (UC), and psoriatic arthritis (PsA) tofacitinib clinical programs. METHODS: Available data from phase 1, randomized phase 2/3/3b/4 clinical trials (completed by 2018), and long-term extension (LTE) studies (up to May 2019) in patients with RA, UC, and PsA were included [randomized or Overall (phase 1-3b/4 and LTE studies) tofacitinib cohorts]. Incidence rates (IRs; events per 100 patient-years) of combined influenza AEs (seasons 2004/2005 to 2018/2019) were analyzed, including by tofacitinib dose [5 or 10 mg twice daily (BID)] and age (< 65 versus ≥ 65 years). Logistic regression models evaluated risk factors for influenza AEs in the RA Overall tofacitinib cohort. RESULTS: In randomized cohorts, combined influenza AE IRs were generally similar across tofacitinib, adalimumab, methotrexate, and placebo groups, across indications. Among Overall tofacitinib cohorts, combined influenza AE IRs with tofacitinib 5/10 mg BID, respectively, were higher in the UC (3.66/5.09) versus RA (2.38/2.19) and PsA (1.74/1.29) cohorts. IRs were generally similar across tofacitinib dose and age groups. Most influenza AEs were nonserious and did not require changes to tofacitinib treatment. Significant risk factors for influenza AEs in patients with RA were geographic region, baseline oral corticosteroid and methotrexate use, and tofacitinib dose. CONCLUSIONS: In the RA, UC, and PsA clinical programs, combined influenza AE IRs were highest in UC, while in each indication they were generally similar across tofacitinib, placebo, and comparator groups. Influenza AEs were predominantly nonserious and not associated with changes to tofacitinib treatment. TRIAL REGISTRATION NUMBERS: NCT01262118, NCT01484561, NCT00147498, NCT00413660, NCT00550446, NCT00603512, NCT00687193, NCT01164579, NCT00976599, NCT01059864, NCT01359150, NCT02147587, NCT00960440, NCT00847613, NCT00814307, NCT00856544, NCT00853385, NCT01039688, NCT02281552, NCT02187055, NCT02831855, NCT00413699, NCT00661661, NCT00787202, NCT01465763, NCT01458951, NCT01458574, NCT01470612, NCT01877668, NCT01882439, NCT01976364.

Cholesterol crystals use complement to increase NLRP3 signaling pathways in coronary and carotid atherosclerosis.

BACKGROUND: During atherogenesis, cholesterol precipitates into cholesterol crystals (CC) in the vessel wall, which trigger plaque inflammation by activating the NACHT, LRR and PYD domains-containing protein 3 (NLRP3) inflammasome. We investigated the relationship between CC, complement and NLRP3 in patients with cardiovascular disease. METHODS: We analysed plasma, peripheral blood mononuclear cells (PBMC) and carotid plaques from patients with advanced atherosclerosis applying ELISAs, multiplex cytokine assay, qPCR, immunohistochemistry, and gene profiling. FINDINGS: Transcripts of interleukin (IL)-1beta(ß) and NLRP3 were increased and correlated in PBMC from patients with acute coronary syndrome (ACS). Priming of these cells with complement factor 5a (C5a) and tumour necrosis factor (TNF) before incubation with CC resulted in increased IL-1ß protein when compared to healthy controls. As opposed to healthy controls, systemic complement was significantly increased in patients with stable angina pectoris or ACS. In carotid plaques, complement C1q and C5b-9 complex accumulated around CC-clefts, and complement receptors C5aR1, C5aR2 and C3aR1 were higher in carotid plaques compared to control arteries. Priming human carotid plaques with C5a followed by CC incubation resulted in pronounced release of IL-1ß, IL-18 and IL-1α. Additionally, mRNA profiling demonstrated that C5a and TNF priming followed by CC incubation upregulated plaque expression of NLRP3 inflammasome components. INTERPRETATION: We demonstrate that CC are important local- and systemic complement activators, and we reveal that the interaction between CC and complement could exert its effect by activating the NLRP3 inflammasome, thus promoting the progression of atherosclerosis.

OXR1A, a Coactivator of PRMT5 Regulating Histone Arginine Methylation.

Oxidation resistance gene 1 (OXR1) protects cells against oxidative stress. We find that male mice with brain-specific isoform A knockout (Oxr1A-/-) develop fatty liver. RNA sequencing of male Oxr1A-/- liver indicates decreased growth hormone (GH) signaling, which is known to affect liver metabolism. Indeed, Gh expression is reduced in male mice Oxr1A-/- pituitary gland and in rat Oxr1A-/- pituitary adenoma cell-line GH3. Oxr1A-/- male mice show reduced fasting-blood GH levels. Pull-down and proximity ligation assays reveal that OXR1A is associated with arginine methyl transferase PRMT5. OXR1A-depleted GH3 cells show reduced symmetrical dimethylation of histone H3 arginine 2 (H3R2me2s), a product of PRMT5 catalyzed methylation, and chromatin immunoprecipitation (ChIP) of H3R2me2s shows reduced Gh promoter enrichment. Finally, we demonstrate with purified proteins that OXR1A stimulates PRMT5/MEP50-catalyzed H3R2me2s. Our data suggest that OXR1A is a coactivator of PRMT5, regulating histone arginine methylation and thereby GH production within the pituitary gland.

Complement component C3 and the TLR co-receptor CD14 are not involved in angiotensin II induced cardiac remodelling.

Inflammation is centrally involved in the development of cardiac hypertrophy and the processes of remodelling. The complement system and Toll-like receptor (TLR) family, two upstream arms of the innate immune system, have previously been reported to be involved in cardiac remodelling. However, the role of complement component 3 (C3), TLR co-receptor CD14 and the synergy between them have not been addressed during pressure overload-induced cardiac remodelling. Here, we examined angiotensin II-induced cardiac hypertrophy and remodelling for 7 days in male C57Bl/6 J mice deficient in C3, CD14, or both (C3CD14), and WT controls. Angiotensin II infusion induced a mild concentric hypertrophic phenotype in WT mice with increased left ventricle weight, wall thicknesses and reduced ventricular internal diameter, associated with increased cardiac fibrosis. However, there were no differences between WT mice and mice deficient for C3, CD14 or C3CD14, as systolic blood pressure, cardiac function and structure and levels of fibrosis were comparable between WT mice and the three other genotypes. C5a did not change in angiotensin II treated mice, whereas Mac2 levels were increased in angiotensin II treated mice, but did not differ between genotypes. The inflammatory IL-6 response was comparable between WT and C3 deficient mice, however, it was decreased in CD14 and C3CD14 deficient mice. We conclude that deficiency in C3, CD14 or C3CD14 had no effect on cardiac remodelling following angiotensin II-induced pressure overload. This suggests that C3 and CD14 are not involved in angiotensin II-induced adverse cardiac remodelling.

Absence of NLRP3 Inflammasome in Hematopoietic Cells Reduces Adverse Remodeling After Experimental Myocardial Infarction.

An inflammatory response is required for tissue healing after a myocardial infarction (MI), but the process must be balanced to prevent maladaptive remodeling. This study shows that improved survival and cardiac function following MI, in mice deficient for the NLRP3 inflammasome, can be recapitulated in wild-type mice receiving bone marrow from Nlrp3 -/- mice. This suggests that NLRP3 activation in hematopoietic cells infiltrating in the myocardium increases mortality and late ventricular remodeling. Our data should encourage performing clinical trials directly targeting NLRP3 inflammasome and their inflammatory cytokines (interleukin-1ß and -18) in MI patients.

Legumain is upregulated in acute cardiovascular events and associated with improved outcome - potentially related to anti-inflammatory effects on macrophages.

BACKGROUND AND AIMS: We have previously found increased levels of the cysteine protease legumain in plasma and plaques from patients with carotid atherosclerosis. This study further investigated legumain during acute cardiovascular events. METHODS: Circulating levels of legumain from patients and legumain released from platelets were assessed by enzyme-linked-immunosorbent assay. Quantitative PCR and immunoblotting were used to study expression, while localization was visualized by immunohistochemistry. RESULTS: In the SUMMIT Malmö cohort (n = 339 with or without type 2 diabetes and/or cardiovascular disease [CVD], and 64 healthy controls), the levels of circulating legumain were associated with the presence of CVD in non-diabetics, with no relation to outcome. In symptomatic carotid plaques and in samples from both coronary and intracerebral thrombi obtained during acute cardiovascular events, legumain was co-localized with macrophages in the same regions as platelets. In vitro, legumain was shown to be present in and released from platelets upon activation. In addition, THP-1 macrophages exposed to releasate from activated platelets showed increased legumain expression. Interestingly, primary peripheral blood mononuclear cells stimulated with recombinant legumain promoted anti-inflammatory responses. Finally, in a STEMI population (POSTEMI; n = 272), patients had significantly higher circulating legumain before and immediately after percutaneous coronary intervention compared with healthy controls (n = 67), and high levels were associated with improved outcome. CONCLUSIONS: Our data demonstrate for the first time that legumain is upregulated during acute cardiovascular events and is associated with improved outcome.

Soluble Markers of Interleukin 1 Activation as Predictors of First-Time Myocardial Infarction in HIV-Infected Individuals.

People with human immunodeficiency virus (HIV) infection (PWH) have an increased risk of cardiovascular disease (CVD), compared with the general population. In a nested case-control study of 55 PWH with first-time myocardial infarction (MI; cases) and 182 PWH with no CVD (controls), we measured soluble markers of interleukin 1 (IL-1) activation at 4 different time points before the case's MI. Cases had higher levels of IL-1 receptor antagonist (IL-1Ra) at all time points leading up to first-time MI, and higher levels of IL-1Ra were associated with an approximately 1.5-fold increased risk of MI, supporting the rationale to target IL-1 activation to reduce cardiovascular risk in PWH.

Serum levels of inflammation-related markers and metabolites predict response to neoadjuvant chemotherapy with and without bevacizumab in breast cancers.

Angiogenesis is necessary for tumor growth and has been targeted in breast cancer; however, it is unclear which patients will respond and benefit from antiangiogenic therapy. We report noninvasive monitoring of patient response to neoadjuvant chemotherapy given alone or in combination with anti-vascular endothelial growth factor (bevacizumab) in a randomized clinical trial. At four time points during neoadjuvant chemotherapy ± bevacizumab of receptor tyrosine-protein kinase erbB-2-negative breast cancers, we measured metabolites and inflammation-related markers in patient's serum. We report significant changes in the levels of several molecules induced by bevacizumab, the most prominent being an increase in pentraxin 3 (PTX3) and von Willebrand factor (VWF). Serum levels of AXL, VWF and pulmonary and activation-regulated cytokine (PARC/CCL18) reflected response to chemotherapy alone or in combination with bevacizumab. We further analyzed serum cytokines in relation to tumor characteristics such as gene expression, tumor metabolites and tumor infiltrating leukocytes. We found that VWF and growth-differentiation factor 15 tumor mRNA levels correlated with their respective serum protein levels suggesting that these cytokines may be produced by tumors and outflow to the bloodstream while influencing the tumor microenvironment locally. Finally, we used binomial logistic regression which allowed to predict patient's response using only 10 noninvasive biomarkers. Our study highlights the potential of monitoring circulating levels of cytokines and metabolites during breast cancer therapy.

Selective and marked decrease of complement receptor C5aR2 in human thoracic aortic aneurysms: a dysregulation with potential inflammatory effects.

Objective: The aetiology of thoracic aortic aneurysm (TAA) is largely unknown, but inflammation is likely to play a central role in the pathogenesis. In this present study, we aim to investigate the complement receptors in TAA. Methods: Aortic tissue and blood from 31 patients with non-syndromic TAA undergoing thoracic aortic repair surgery were collected. Aortic tissue and blood from 36 patients with atherosclerosis undergoing coronary artery bypass surgery or aortic valve replacement were collected and served as control material. The expression of the complement anaphylatoxin receptors C3aR1, C5aR1 and C5aR2 in aortic tissue were examined by quantitative RT-PCR and C5aR2 protein by immunohistochemistry. Colocalisation of C5aR2 to different cell types was analysed by immunofluorescence. Complement activation products C3bc and sC5b-9 were measured in plasma. Results: Compared with controls, TAA patients had substantial (73%) downregulated gene expression of C5aR2 as seen both at the mRNA (p=0.005) level and protein (p=0.03) level. In contrast, there were no differences in the expression of C3aR1 and C5aR1 between the two groups. Immunofluorescence examination showed that C5aR2 was colocalised to macrophages and T cells in the aortic media. There were no differences in the degree of systemic complement activation between the two groups. Conclusion: Our findings suggest downregulation of the C5aR2, regarded to act mainly anti-inflammatory, in electively operated TAA as compared with non-aneurysmatic aortas of patients with aortic stenosis and/or coronary artery disease. This may tip the balance towards a relative increase in the inflammatory responses induced by C5aR1 and thus enhance the inflammatory processes in TAA.

Low Cellular NAD+ Compromises Lipopolysaccharide-Induced Inflammatory Responses via Inhibiting TLR4 Signal Transduction in Human Monocytes.

NAD+ is an essential cofactor in reduction-oxidation metabolism with impact on metabolic and inflammatory diseases. However, data elucidating the effects of NAD+ on the proinflammatory features of human primary monocytes are scarce. In this study, we explored how NAD+ affects TLR4 and NOD-like receptor with a PYD-domain 3 (NLRP3) inflammasome activation, two key innate immune responses. Human primary monocytes were isolated from buffy coats obtained from healthy individuals. Intracellular NAD+ was manipulated by nicotinamide riboside and the NAMPT inhibitor FK866. Cells were primed with LPS with or without subsequent NLRP3 activation with ATP or cholesterol crystals to analyze the effects of NAD+ levels on TLR4-mediated NF-κB activation and NLRP3 activity, respectively. Cytokine release was quantified, and the downstream signal pathway of TLR4 was investigated with Western blot and proteomic analysis. The impact of sirtuin and PARP inhibition was also explored. Our main findings were: 1) elevated NAD+ enhanced IL-1ß release in LPS-primed human monocytes exposed to ATP in vitro, 2) both NLRP3-dependent and -independent inflammatory responses in LPS-exposed monocytes were inhibited by NAD+ depletion with FK866, 3) the inhibition was not caused by suppression of sirtuins or PARP1, and 4) phosphorylation of several proteins TLR4 signal pathway was inhibited by FK866-mediated NAD+ depletion, specifically TAK1, IKKß, IkBα, MEK 1/2, ERK 1/2, and p38. Hence, we suggest a novel mechanism in which NAD+ affects TLR4 signal transduction. Furthermore, our data challenge previous reports of the interaction between NAD+ and inflammation and question the use of nicotinamide riboside in the therapy of inflammatory disorders.

Impaired HDL Function Amplifies Systemic Inflammation in Common Variable Immunodeficiency.

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency, characterized by inadequate antibody responses and recurrent bacterial infections. Paradoxically, a majority of CVID patients have non-infectious inflammatory and autoimmune complications, associated with systemic immune activation. Our aim was to explore if HDL, known to have anti-inflammatory properties, had impaired function in CVID patients and thereby contributed to their inflammatory phenotype. We found reduced HDL cholesterol levels in plasma of CVID patients compared to healthy controls, particularly in patients with inflammatory and autoimmune complications, correlating negatively with inflammatory markers CRP and sCD25. Reverse cholesterol transport capacity testing showed reduced serum acceptance capacity for cholesterol in CVID patients with inflammatory and autoimmune complications. They also had reduced cholesterol efflux capacity from macrophages to serum and decreased expression of ATP-binding cassette transporter ABCA1. Human HDL suppressed TLR2-induced TNF release less in blood mononuclear cells from CVID patients, associated with decreased expression of transcriptional factor ATF3. Our data suggest a link between impaired HDL function and systemic inflammation in CVID patients, particularly in those with autoimmune and inflammatory complications. This identifies HDL as a novel therapeutic target in CVID as well as other more common conditions characterized by sterile inflammation or autoimmunity.

Mammalian Target of Rapamycin (mTOR) and the Proteasome Attenuates IL-1ß Expression in Primary Mouse Cardiac Fibroblasts.

Background: IL-1ß is a highly potent pro-inflammatory cytokine and its secretion is tightly regulated. Inactive pro-IL-1ß is transcribed in response to innate immune receptors activating NFκB. If tissue damage occurs, danger signals released from necrotic cells, such as ATP, can activate NLRP3-inflammasomes (multiprotein complexes consisting of NLRP3, ASC, and active caspase-1) which cleaves and activates pro-IL-1ß. NLRP3 activation also depends on NEK7 and mitochondrial ROS-production. Thus, IL-1ß secretion may be regulated at the level of each involved component. We have previously shown that NLRP3-dependent IL-1ß release can be induced in cardiac fibroblasts by pro-inflammatory stimuli. However, anti-inflammatory mechanisms targeting IL-1ß release in cardiac cells have not been investigated. mTOR is a key regulator of protein metabolism, including autophagy and proteasome activity. In this study we explored whether autophagy or proteasomal degradation are regulators of NLRP3 inflammasome activation and IL-1ß release from cardiac fibroblasts. Methods and Results: Serum starvation selectively reduced LPS/ATP-induced IL-1ß secretion from cardiac fibroblasts. However, no other inflammasome components, nor mitochondrial mass, were affected. The mTOR inhibitor rapamycin restored pro-IL-1ß protein levels as well as LPS/ATP-induced IL-1ß release from serum starved cells. However, neither serum starvation nor rapamycin induced autophagy in cardiac fibroblasts. Conversely, chloroquine and bafilomycin A (inhibitors of autophagy) and betulinic acid (a proteasome activator) effectively reduced LPS-induced pro-IL-1ß protein levels. Key findings were reinvestigated in human monocyte-derived macrophages. Conclusion: In cardiac fibroblasts, mTOR inhibition selectively favors pro-IL-1ß synthesis while proteasomal degradation and not autophagy is the major catabolic anti-inflammatory mechanism for degradation of this cytokine.

Caspase-1 induces smooth muscle cell growth in hypoxia-induced pulmonary hypertension.

Lung diseases with hypoxia are complicated by pulmonary hypertension, leading to heart failure and death. No pharmacological treatment exists. Increased proinflammatory cytokines are found in hypoxic patients, suggesting an inflammatory pathogenesis. Caspase-1, the effector of the inflammasome, mediates inflammation through activation of the proinflammatory cytokines interleukin (IL)-18 and IL-1ß. Here, we investigate inflammasome-related mechanisms that can trigger hypoxia-induced pulmonary hypertension. Our aim was to examine whether caspase-1 induces development of hypoxia-related pulmonary hypertension and is a suitable target for therapy. Wild-type (WT) and caspase-1-/- mice were exposed to 10% oxygen for 14 days. Hypoxic caspase-1-/- mice showed lower pressure and reduced muscularization in pulmonary arteries, as well as reduced right ventricular remodeling compared with WT. Smooth muscle cell (SMC) proliferation was reduced in caspase-1-deficient pulmonary arteries and in WT arteries treated with a caspase-1 inhibitor. Impaired inflammation was shown in hypoxic caspase-1-/- mice by abolished pulmonary influx of immune cells and lower levels of IL-18, IL-1ß, and IL-6, which were also reduced in the medium surrounding caspase-1 abrogated pulmonary arteries. By adding IL-18 or IL-1ß to caspase-1-deficient pulmonary arteries, SMC proliferation was retained. Furthermore, inhibition of both IL-6 and phosphorylated STAT3 reduced proliferation of SMC in vitro, indicating IL-18, IL-6, and STAT3 as downstream mediators of caspase-1-induced SMC proliferation in pulmonary arteries. Caspase-1 induces SMC proliferation in pulmonary arteries through the caspase-1/IL-18/IL-6/STAT3 pathway, leading to pulmonary hypertension in mice exposed to hypoxia. We propose that caspase-1 inhibition is a potential target for treatment of pulmonary hypertension.

Neuromodulatory Effect of NLRP3 and ASC in Neonatal Hypoxic Ischemic Encephalopathy.

BACKGROUND: Following birth asphyxia there is a robust inflammatory response. NLRP3 is a receptor of the innate immune system. Upon activation, NLRP3 forms an inflammasome together with ASC and procaspase-1 to mediate release of IL-1ß and IL-18. NLRP3 has previously been shown to be upregulated following neonatal hypoxic-ischemic (HI) brain injury in mice, but with no early effect on brain injury. OBJECTIVE: We aimed to evaluate if deficiency of NLRP3 or ASC protects against neonatal HI brain damage 7 days after hypoxia-ischemia. METHODS: C57BL/6J, NLRP3-/-, and ASC-/- mice were subjected to unilateral common carotid artery ligation followed by hypoxia at P9. Brain infarction, apoptosis, and microglial response were evaluated, as well as total RNA sequencing and examination of plasma levels of systemic proinflammatory cytokines. RESULTS: NLRP3-/- mice showed significantly increased brain infarction volumes compared to wild-type (Wt) mice, while ASC-/- mice showed reduced brain infarction volumes after neonatal hypoxia-ischemia. The amount of activated microglia was increased in NLRP3-/- mice, while decreased in ASC-/- mice compared to Wt mice. Total RNA sequencing showed an impaired inflammatory transcriptional response in the hippocampus of NLRP3-/- mice. Plasma levels of IL-1ß and IL-18 were not affected, but TNF was lower in NLRP3-/- and ASC-/- mice compared to Wt mice. CONCLUSION: ASC deficiency is neuroprotective in neonatal HI brain damage in mice, while NLRP3 deficiency increases brain damage.