Interleukin-23: A New Atherosclerosis Target

Risk of Major Adverse Cardiovascular Events in Immune-Mediated Inflammatory Disorders on Biologics and Small Molecules: Network Meta-Analysis

BACKGROUND AND AIMS

Recent studies raise concern for increased risk of major adverse cardiovascular events (MACE) with Janus kinase (JAK) inhibitors used to treat immune-mediated inflammatory disorders (IMIDs). We aimed to examine MACE risk with licensed biologics and small molecules used commonly between IMIDs: inflammatory bowel disease, rheumatoid arthritis, psoriasis/psoriatic arthritis, and ankylosing spondylitis.

METHODS

Data were obtained from systematic searches (from inception to May 31, 2022) in PubMed, Embase, Ovid Medline, Scopus, Cochrane Central, and ClinicalTrials.gov. Studies that assessed a predefined MACE (myocardial infarction, cerebrovascular accident, unstable angina, cardiovascular death, or heart failure) risk in those ≥18 years of age with IMIDs treated with anti-interleukin (IL)-23 antibodies, anti-IL-12/23, anti-tumor necrosis factor α antibodies (anti-TNF-α), or JAK inhibitors were included in a network meta-analysis using a random-effects model with pooled odds ratios (ORs) reported with 95% credible intervals (CrIs) by drug class and disease state.

RESULTS

Among 3528 studies identified, 40 (36 randomized controlled trials and 4 cohort studies) were included in the systematic review, comprising 126,961 patients with IMIDs. Based on network meta-analysis of randomized controlled trials, regardless of disease state, anti-TNF-α (OR, 2.49; 95% CrI, 1.14-5.62), JAK inhibitors (OR, 2.64; 95% CrI, 1.26-5.99), and anti-IL-12/23 (OR, 3.15; 95% CrI, 1.01-13.35) were associated with increased MACE risk compared with placebo. There was no significant difference in the magnitude of the MACE risk between classes or based on IMID type.

CONCLUSIONS

Anti-IL-12/23, JAK inhibitors, and anti-TNF-α were associated with higher risk of MACE compared with placebo. The magnitude of the increased MACE risk was not different by IMID type. These results require confirmation in larger prospective studies.

Polymorphism of IL-12/IL-23 axis is associated with coronary heart disease

IL12B encodes the shared p40 subunit (IL-12p40) of IL-12 and IL-23, which have diverse immune functions and are closely related to the occurrence and development of atherosclerosis (AS). However, the exact role of IL12B in coronary heart disease (CHD) was still unknown. A case-control association analysis was performed between five single nucleotide polymorphisms (SNPs) of IL12B (rs1003199, rs3212219, rs2569254, rs2853694 and rs3212227) and CHD in Chinese Han population (1824 patients with CHD vs. 2784 controls). Logistic regression analyses were used to study the relationships between SNPs and CHD, while multiple linear regression analyses were used to test the association between the SNP and the severity of CHD. In addition, the plasma IL12B concentration of CHD patients were detected by ELISA. We detected a significant association between one of the SNPs, rs2853694-G and CHD (padj  = 2.075 × 10-5 , OR, 0.773 [95% CI, 0.686-0.870]). Stratified analysis showed that rs2853694 was associated with CHD in both male and female populations and was significantly associated with both early- and late-onset CHD. In addition, rs2853694 is also related to the different types of CHD including clinical-CHD and anatomical-CHD. Moreover, there are significant differences in serum IL12B concentrations between rs2853694-TT carriers and rs2853694-GT carriers in CHD patients (p = 0.010). A common variant of IL12B was found significantly associated with CHD and its subgroups. As a shared subunit of IL-12 and IL-23, IL-12p40 may play a key role in IL-12/IL-23 axis mediated AS, which is expected to be an effective therapeutic target for CHD.

Cross-Sectional Gene-Smoking Interaction Analysis in Relation to Subclinical Atherosclerosis-Results From the IMPROVE Study

BACKGROUND

Smoking is associated with carotid intima-media thickness (C-IMT). However, knowledge about how genetics may influence this association is limited. We aimed to perform nonhypothesis driven gene-smoking interaction analyses to identify potential genetic variants, among those included in immune and metabolic platforms, that may modify the effect of smoking on carotid intima-media thickness.

METHODS

We used baseline data from 1551 men and 1700 women, aged 55 to 79, included in a European multi-center study. Carotid intima-media thickness maximum, the maximum of values measured at different locations of the carotid tree, was dichotomized with cut point values ≥75, respectively. Genetic data were retrieved through use of the Illumina Cardio-Metabo- and Immuno- Chips. Gene-smoking interactions were evaluated through calculations of Synergy index (S). After adjustments for multiple testing, P values of <2.4×10-7 for S were considered significant. The models were adjusted for age, sex, education, physical activity, type of diet, and population stratification.

RESULTS

Our screening of 207 586 SNPs available for analysis, resulted in the identification of 47 significant gene-smoking synergistic interactions in relation to carotid intima-media thickness maximum. Among the significant SNPs, 28 were in protein coding genes, 2 in noncoding RNA and the remaining 17 in intergenic regions.

CONCLUSIONS

Through nonhypothesis-driven analyses of gene-smoking interactions, several significant results were observed. These may stimulate further research on the role of specific genes in the process that determines the effect of smoking habits on the development of carotid atherosclerosis.

Exploring the hub mechanisms of ischemic stroke based on protein-protein interaction networks related to ischemic stroke and inflammatory bowel disease

Ischemic stroke is highly concerning because it often leads to severe long-term neurological disability. Among clinical trials, ischemic stroke and inflammatory bowel disease interactions have been increasingly reported in recent years. Therefore, using bioinformatics approaches to explore novel protein interactions between them is of interest. We performed this exploratory analysis by using bioinformatics tools such as string to analyze gene data downloaded from NHGRI-GWAS data related to ischemic stroke and inflammatory bowel disease. We constructed a prospective protein interaction network for ischemic stroke and inflammatory bowel disease, identifying cytokine and interleukin-related signaling pathways, Spliceosome, Ubiquitin-Proteasome System (UPS), Thrombus, and Anticoagulation pathways as the crucial biological mechanisms of the network. Furthermore, we also used data-independent acquisition mass spectrometry (DIA-MS) to detect differential protein expression in eight samples, which also suggested that immune system, signal transduction, and hemostasis-related pathways are key signaling pathways. These findings may provide a basis for understanding the interaction between these two states and exploring possible molecular and therapeutic studies in the future.

Identification of heterogeneous subsets of aortic interleukin-17A-expressing CD4+ T cells in atherosclerotic mice

Objectives: T helper 17 (Th17) cells are involved in the inflammatory response of atherosclerosis. However, their heterogeneity in the atherosclerotic aorta remains elusive. This study was designed to identify aortic Th17 subsets. Methods: The surface markers and transcription factors of aortic interleukin-17A (IL-17A)-expressing T cells were determined by flow cytometry in an ApoE-deficient mouse atherosclerotic model. Viable aortic IL-17A-expressing T cell subsets were isolated by flow cytometry on the basis of surface markers, followed by characterizing their transcription factors by either flow cytometry or real-time RT-PCR. The effect of aortic IL-17A-expressing T cell subsets on aortic endothelial cells was determined in vitro. Results: C-X-C Motif Chemokine Receptor 3 (CXCR3), interleukin-17 receptor E (IL-17RE), CD200, and C-C Motif Chemokine Receptor 4 (CCR4) marked three subsets of aortic IL-17A-expressing T cells: CXCR3⁺IL-17RE^lowCD200⁺CCR4^- T cells expressing T-box protein expressed in T cells (T-bet) and interferon-gamma (IFN-γ), CXCR3⁺IL-17RE^lowCD200⁺CCR4⁺ T cells expressing T-bet but fewer IFN-γ, and CXCR3⁻IL-17RE^highCD200⁺CCR4⁺ T cells expressing very low T-bet and no IFN-γ. Based on these markers, viable aortic Th17 cells, Th17.1 cells, and transitional Th17.1 cells were identified. Both Th17.1 cells and transitional Th17.1 cells were more proliferative than Th17 cells. Compared with Th17 cells, Th17.1 cells plus transitional Th17.1 cells induced higher expression of C-X-C motif chemokine ligand 1 (CXCL1), C-C motif chemokine ligand 2 (CCL2), C-X-C motif chemokine 5 (CXCL5), and granulocyte-macrophage colony-stimulating factor (GM-CSF) in aortic endothelial cells. Conclusion: IL-17A-expressing CD4⁺ T cells were heterogeneous in atherosclerotic aortas.

Microglia-Derived Interleukin 23: A Crucial Cytokine in Alzheimer's Disease?

Neuronal cell death, amyloid β plaque formation and development of neurofibrillary tangles are among the characteristics of Alzheimer's disease (AD). In addition to neurodegeneration, inflammatory processes such as activation of microglia and astrocytes are crucial in the pathogenesis and progression of AD. Cytokines are essential immune mediators of the immune response in AD. Recent data suggest a role of interleukin 23 (IL-23) and its p40 subunit in the pathogenesis of AD and corresponding animal models, in particular concerning microglia activation and amyloid β plaque formation. Moreover, in animal models, the injection of anti-p40 antibodies resulted in reduced amyloid β plaque formation and improved cognitive performance. Here, we discuss the pathomechanism of IL-23 mediated inflammation and its role in AD.

Role of interleukin-23/interleukin-17 axis in T-cell-mediated actions in hypertension

Current knowledge suggests that hypertension is in part mediated by immune mechanisms. Both interleukin (IL)-23 and IL-17 are up-regulated in several experimental hypertensive rodent models, as well as in hypertensive humans in observational studies. Recent preclinical studies have shown that either IL-23 or IL-17A treatment induce blood pressure elevation. However, the IL-23/IL-17 axis has not been a major therapeutic target in hypertension, unlike in other autoimmune diseases. In this review, we summarize current knowledge on the role of these cytokines in immune mechanisms contributing to hypertension, and discuss the potential of IL-23/IL-17-targeted therapy for treatment of hypertension.

The Effects of Anti-IL-23p19 Therapy on Atherosclerosis Development in ApoE-/- Mice

The aim of this study is to detect the dynamic expression of interleukin-23 (IL-23) in ApoE^-/- mice at different ages and to further examine the effects of anti-IL-23 therapy on atherosclerosis development. The levels of IL-23 in the sera, aortas, and lymph nodes of ApoE^-/- mice were significantly increased compared with those of age-matched controls at 8, 12, 16, 20, and 24 weeks of age. Then, 12-week-old ApoE^-/- mice were intraperitoneally injected with anti-IL-23p19 neutralizing antibodies, isotype controls, and phosphate-buffered saline for 8 weeks. The proinflammatory and anti-inflammatory mediators in atherosclerotic aortas, plaque areas, plaque necrotic cores, and the contents of major inflammatory cells in plaques were subsequently determined. The results showed that anti-IL-23p19 treatment significantly decreased the expression of IL-17A, IL-6, and TNF-α in the aortas of ApoE^-/- mice, but had no obvious effect on the plaque area, plaque necrotic core, or content of major inflammatory cells in atherosclerotic plaques. Although anti-IL-23p19 therapy reduces the expression of several proinflammatory cytokines, it does not significantly suppress the progression of atherosclerosis in ApoE^-/- mice.