Association of soluble interleukin-2 receptor α and tumour necrosis factor receptor 1 with heart failure: The Multi-Ethnic Study of Atherosclerosis

IL-2Rα is a potential biomarker for heart failure diagnosis of patients with end-stage renal disease and haemodialysis

AIMS

Heart failure (HF) is a leading cause of mortality in patients with end-stage renal disease (ESRD) undergoing haemodialysis. Identifying novel predictors of HF is essential for improving diagnostic precision and enhancing patient outcomes.

METHODS

This study included 68 participants from the Haemodialysis Centre at the Second Hospital of Tianjin Medical University. Clinical characteristics and echocardiographic data were collected and analysed. We measured the plasma of 44 cytokines to investigate their correlation with cardiac function and their potential as HF biomarkers.

RESULTS

In the HF with reduced ejection fraction (HFrEF) group, the levels of several cytokines, including stem cell growth factor-β (SCGF-β), C-X-C motif chemokine 10 (CXCL10), interleukin-1α (IL-1α), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-16 (IL-16), interleukin-1 receptor antagonist protein (IL-1Ra), interferon-γ (IFN-γ), tumour necrosis factor-α (TNF-α), leukaemia inhibitory factor (LIF), C-C motif chemokine 3 (CCL3), interleukin-10 (IL-10), interleukin-2 receptor subunit alpha (IL-2Rα), tumour necrosis factor ligand superfamily member 10 (TNFSF10), macrophage colony-stimulating factor (M-CSF), granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF), were significantly increased, while C-C motif chemokine 11 (CCL11)/eotaxin levels were decreased compared with those in the control group (P < 0.05). Receiver operating characteristic (ROC) curve analysis highlighted TNF-α [area under the ROC curve (AUC) = 0.85, odds ratio (OR) = 1.080, 95% confidence interval (CI): 1.033-1.128, P = 0.001], IFN-γ (AUC = 0.84, OR = 1.836, 95% CI: 1.289-2.615, P = 0.003) and IL-2Rα (AUC = 0.82, OR = 1.022, 95% CI: 1.009-1.035, P = 0.001) as excellent predictors for HFrEF in haemodialysis patients with ESRD, and they outperformed soluble suppression of tumourigenicity-2 (sST2) but slightly underperformed N-terminal pro-brain natriuretic peptide (NT-proBNP). IL-2Rα (AUC = 0.77, OR = 1.018, 95% CI: 1.007-1.030, P = 0.001) demonstrated superior diagnostic capabilities when distinguishing patients with HF with left ventricular ejection fraction (LVEF) <50% from controls. IL-2Rα emerged as a robust biomarker for left ventricular HF, while TNF-α (AUC = 0.89, OR = 1.140, 95% CI: 1.039-1.250, P = 0.005) showed promise in assessing HF severity in patients with ESRD. IL-2Rα (AUC = 0.80, OR = 1.017, 95% CI: 1.007-1.027, P = 0.001) also significantly predicted right ventricular systolic dysfunction. During a median follow-up of 14 months, 10 patients (14.7%) experienced all-cause mortality. Multivariate Cox regression analysis confirmed that plasma IL-2Rα was an independent predictor of all-cause death [hazard ratio (HR): 1.010, 95% CI: 1.001-1.020, P = 0.039] after adjusting for other variables.

CONCLUSIONS

This study underscores the potential of IL-2Rα as a valuable biomarker for HF diagnosis and management in haemodialysis patients with ESRD and contributes to our understanding of this high-risk population.

Sodium-glucose cotransporter 2 inhibitors, inflammation, and heart failure: a two-sample Mendelian randomization study

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT-2) inhibitors are increasingly recognized for their role in reducing the risk and improving the prognosis of heart failure (HF). However, the precise mechanisms involved remain to be fully delineated. Evidence points to their potential anti-inflammatory pathway in mitigating the risk of HF.

METHODS

A two-sample, two-step Mendelian Randomization (MR) approach was employed to assess the correlation between SGLT-2 inhibition and HF, along with the mediating effects of inflammatory biomarkers in this relationship. MR is an analytical methodology that leverages single nucleotide polymorphisms as instrumental variables to infer potential causal inferences between exposures and outcomes within observational data frameworks. Genetic variants correlated with the expression of the SLC5A2 gene and glycated hemoglobin levels (HbA1c) were selected using datasets from the Genotype-Tissue Expression project and the eQTLGen consortium. The Genome-wide association study (GWAS) data for 92 inflammatory biomarkers were obtained from two datasets, which included 14,824 and 575,531 individuals of European ancestry, respectively. GWAS data for HF was derived from a meta-analysis that combined 26 cohorts, including 47,309 HF cases and 930,014 controls. Odds ratios (ORs) and 95% confidence interval (CI) for HF were calculated per 1 unit change of HbA1c.

RESULTS

Genetically predicted SGLT-2 inhibition was associated with a reduced risk of HF (OR 0.42 [95% CI 0.30-0.59], P < 0.0001). Of the 92 inflammatory biomarkers studied, two inflammatory biomarkers (C-X-C motif chemokine ligand 10 [CXCL10] and leukemia inhibitory factor) were associated with both SGLT-2 inhibition and HF. Multivariable MR analysis revealed that CXCL10 was the primary inflammatory cytokine related to HF (MIP = 0.861, MACE = 0.224, FDR-adjusted P = 0.0844). The effect of SGLT-2 inhibition on HF was mediated by CXCL10 by 17.85% of the total effect (95% CI [3.03%-32.68%], P = 0.0183).

CONCLUSIONS

This study provides genetic evidence supporting the anti-inflammatory effects of SGLT-2 inhibitors and their beneficial impact in reducing the risk of HF. CXCL10 emerged as a potential mediator, offering a novel intervention pathway for HF treatment.

Soluble TNFR1 has greater reproducibility than IL-6 for the assessment of chronic inflammation in older adults: the case for a new inflammatory marker in aging

Chronic inflammatory pathway activation, commonly referred to as "Inflammaging" or chronic inflammation (CI), is associated with frailty, cognitive and functional decline, and other causes of health span decline in older adults. We investigated the variability of candidate serum measures of CI among community-dwelling older adults selected for mild low-grade inflammation. We focused on serum cytokines known to be highly predictive of adverse health outcomes in older adults (sTNFR1, IL-6) during a short-term (weeks) and medium-term (months) follow-up, as well as immune markers that are less studied in aging but reflect other potentially relevant domains such as adaptive immune activation (sCD25), innate immune activation (sCD14 and sCD163), and the inflammation-metabolism interface (adiponectin/Acrp30) during short-term (weeks) follow up. We found that sTNFR1 was more reproducible than IL-6 over a period of weeks and months short-term and medium-term. The intra-class correlation coefficient (ICC) for sTNFR1 was 0.95 on repeated measures over 6 weeks, and 0.79 on repeated measures with mean interval of 14 weeks, while the ICC for IL-6 was 0.52 over corresponding short-term and 0.67 over corresponding medium-term follow-up. This suggests that sTNFR1 is a more reliable marker of CI than IL-6. This study provides new insights into the reproducibility of serum markers of CI in older adults. The findings suggest that sTNFR1 may be a better marker of CI than IL-6 in this population. Further studies are needed to confirm these findings and to investigate the clinical utility of sTNFR1 in older adults.

Selective glomerular hypofiltration syndrome

The estimated glomerular filtration rate (eGFR) provides insight into cardiovascular disease (CVD) risk stratification and proactive management. Accumulating evidence suggests that combining eGFR calculated from serum cystatin C (eGFRcys) and from serum creatinine (eGFRcrea) improves CVD risk stratification over eGFRcrea alone. The term selective glomerular hypofiltration syndrome (SGHS) or shrunken pore syndrome has been proposed to define an eGFRcys:eGFRcrea ratio <1, which is hypothesized to result from a reduced glomerular filtration of 5- to 30-kDa molecules as compared with smaller molecules. SGHS may be identified in people with normal or reduced measured GFR, but the prevalence depends on the cut-off value of the eGFRcys:eGFRcrea ratio used, which is not yet standardized. SGHS is strongly associated with increased CVD and mortality risks and it may offer an opportunity to expand our understanding of the mechanisms linking GFR disorders with CVD risk (e.g. an altered plasma proteome), which may guide treatment decisions. However, muscle wasting may also contribute to a reduced eGFRcys:eGFRcrea ratio and there are open questions regarding the pathophysiology of a reduced eGFRcys:eGFRcrea ratio, the reference cut-off values of the ratio to define the syndrome and its clinical implications. We now critically review the SGHS concept, its pathophysiological basis and links to CVD and the potential consequences for clinical practice and propose a research agenda.

Influence of Interleukin-2 and Brain-Derived Neurotrophic Factor (BDNF) on the Size of Myocardial Infarction in Rats with Systemic Inflammatory Response

We studied the influence of recombinant IL-2 and brain-derived neurotrophic factor (BDNF) on the size of the myocardial necrosis zone of rats with systemic inflammatory response syndrome (SIRS). A significant increase in the necrosis zone and the levels of proinflammatory cytokines was revealed in animals with SIRS in comparison with the control. The administration of IL-2 to animals with SIRS significantly reduced the size of the necrosis zone, which was paralleled by a pronounced increase in IL-2 and BDNF in comparison with the corresponding parameters in rats with SIRS that did not receive IL-2. Administration of BDNF to animals with SIRS was followed by normalization of TNFα and IL-1α levels, but did not lead to a decrease in the size of the necrosis zone.

Soluble interleukin-2 receptor combined with interleukin-8 is a powerful predictor of future adverse cardiovascular events in patients with acute myocardial infarction

Background

Little is known about the role of interleukin (IL) in patients with acute myocardial infarction (MI), especially soluble IL-2 receptor (sIL-2R) and IL-8. We aim to evaluate, in MI patients, the predictive value of serum sIL-2R and IL-8 for future major adverse cardiovascular events (MACEs), and compare them with current biomarkers reflecting myocardial inflammation and injury.

Methods

This was a prospective, single-center cohort study. We measured serum concentrations of IL-1β, sIL-2R, IL-6, IL-8 and IL-10. Levels of current biomarkers for predicting MACEs were measured, including high-sensitivity C reactive protein, cardiac troponin T and N-terminal pro-brain natriuretic peptide. Clinical events were collected during 1-year and a median of 2.2 years (long-term) follow-up.

Results

Twenty-four patients (13.8%, 24/173) experienced MACEs during 1-year follow-up and 40 patients (23.1%, 40/173) during long-term follow-up. Of the five interleukins studied, only sIL-2R and IL-8 were independently associated with endpoints during 1-year or long-term follow-up. Patients with high sIL-2R or IL-8 levels (higher than the cutoff value) had a significantly higher risk of MACEs during 1-year (sIL-2R: HR 7.7, 3.3-18.0, p < 0.001; IL-8: HR 4.8, 2.1-10.7, p < 0.001) and long-term (sIL-2R: HR 7.7, 3.3-18.0, p < 0.001; IL-8: HR 4.8, 2.1-10.7, p < 0.001) follow-up. Receiver operator characteristic curve analysis regarding predictive accuracy for MACEs during 1-year follow-up showed that the area under the curve for sIL-2R, IL-8, sIL-2R combined with IL-8 was 0.66 (0.54-0.79, p = 0.011), 0.69 (0.56-0.82, p < 0.001) and 0.720 (0.59-0.85, p < 0.001), whose predictive value were superior to that of current biomarkers. The addition of sIL-2R combined with IL-8 to the existing prediction model resulted in a significant improvement in predictive power (p = 0.029), prompting a 20.8% increase in the proportion of correct classifications.

Conclusions

High serum sIL-2R combined with IL-8 levels was significantly associated with MACEs during follow-up in patients with MI, suggesting that sIL-2R combined with IL-8 may be a helpful biomarker for identifying the increased risk of new cardiovascular events. IL-2 and IL-8 would be promising therapeutic targets for anti-inflammatory therapy.

Construction of an immune-related signature for predicting the ischemic events in patients undergoing carotid endarterectomy

Background: Inflammatory responses have drawn more attention to atherosclerosis; however, the immune-related genes (IRGs) as a prognostic factor in atherosclerotic plaque remain to be fully elucidated. Here, the purpose of this study was to investigate whether the IRGs could be identified as a reliable biomarker for predicting ischemic events in patients undergoing carotid endarterectomy (CEA). Methods: Two datasets GSE97210 and GSE21545 were downloaded from the Gene Expression Omnibus (GEO) database. The dataset GSE97210 was used to explore the significant pathways and differentially expressed IRGs (DEIRGs) between plaques and controls, which were further screened to identify the prognostic DEIRGs in the GSE21545 dataset. The identification of molecular subgroups with the prognostic gene expression patterns was achieved through nonnegative matrix factorization (NMF) clustering. Functional analyses including GO, KEGG, GSVA, and GSEA analyses, and immune analyses including xCell and ssGSEA algorithms were conducted to elucidate the underlying mechanisms. The prognostic risk model was constructed using the LASSO algorithm and multivariate Cox regression analysis. Results: A total of 796 DEIRGs (including 588 upregulated and 208 downregulated) were identified. Nine prognostic DEIRGs were further screened with univariate Cox regression analysis. Two clusters with different prognosis were grouped based on the prognostic DEIRGs. Immune infiltration analysis shows that cluster 2 with a better prognosis presented with a higher immune response than cluster 1. A prognostic model based on seven IRGs (IL2RA, NR4A2, DES, ERAP2, SLPI, RASGRP1, and AGTR2) was developed and verified. Consistent with the immune analysis of the cluster, the immune infiltration in the low-risk group with a better prognosis was also more active than that in the high-risk group. Finally, a nomogram based on the seven genes was constructed, which might have future implications in clinical care. Conclusion: The expression of immune-related genes is correlated with the immune microenvironment of atherosclerotic patients and could be applied to predict the ischemic events in patients undergoing CEA accurately.

Inflammation and heart failure: a two-sample Mendelian randomization study

BACKGROUND

It is hypothesized that inflammation leads to heart failure. Results from observational studies thus far have been inconsistent and it is unclear whether inflammation is causally associated with new-onset heart failure. Mendelian randomization analyses are less prone to biases common in observational studies such as reverse causation and unmeasured confounding. The aim of this study was to investigate the causal relation between various inflammatory biomarkers with risk of new-onset heart failure by using a two-sample Mendelian randomization approach.

METHODS

Ten inflammatory biomarkers with available genome-wide association studies (GWAS) among individuals of European ancestry were identified and included C-reactive protein (CRP), immunoglobulin E, tumour necrosis factor (TNF), toll-like receptor 4, interleukin 1 receptor antagonist, interleukin 2 receptor subunit α, interleukin 6 receptor subunit α, interleukin 16, 17 and 18. For the associations between the identified SNPs and heart failure, we used the largest GWAS meta-analysis performed by the Heart Failure Molecular Epidemiology for Therapeutic Targets Consortium with 47 309 participants with heart failure and 930 014 controls. For our main analyses, we used the inverse-variance weighted method.

RESULTS

We included 63 SNPs. CRP, TNF, interleukin 2, 16 and 18 were not associated with heart failure with odds ratios (ORs) of 1.01 [95% confidence interval (95% CI: 0.94-1.09), 1.11 (95% CI: 0.80-1.48), 0.97 (95% CI: 0.93-1.02), 0.99 (95% CI: 0.96-1.03) and 1.01 (95% CI: 0.97-1.06), respectively. The other biomarkers were also not associated with the risk of heart failure and suffered from weak instrument bias.

CONCLUSION

This Mendelian randomization study could not determine a causal relationship between inflammation and risk of heart failure. However, some biomarkers suffered from weak instrument bias.

Novel biomarkers of inflammation in heart failure with preserved ejection fraction: analysis from a large prospective cohort study

Background

Heart failure with preserved ejection fraction (HFpEF) is a syndrome with a heterogeneous cluster of causes, including non-resolving inflammation, endothelial dysfunction, and multi-organ defects. The present study’s objective was to identify novel predictors of HFpEF.

Methods

The study analyzed the Multi-Ethnic Study of Atherosclerosis (MESA) to assess the association of specific markers of inflammation with new onset of HFpEF (interleukin-2 [IL-2], matrix metalloproteinase 3 [MMP3], large low-density lipoprotein cholesterol [LDL-C], and medium high-density lipoprotein cholesterol [HDL-C]). The study included men and women 45 to 84 years of age without cardiovascular disease at baseline. The primary outcome was the multivariate association of the hypothesized markers of inflammation with new-onset of HFpEF versus participants without new-onset heart failure. Participants with missing data were excluded.

Results

The present analysis included 6814 participants, 53% female, with a mean age of 62 years. Among the entire cohort, HFpEF was diagnosed in 151 (2.2%) participants and heart failure with reduced ejection fraction (HFrEF) was diagnosed in 146 (2.1%) participants. Participants were followed for the outcome of heart failure for a median 13.9 years. Baseline IL-2 was available for 2861 participants. The multivariate analysis included 2792 participants. Of these, 2668 did not develop heart failure, 62 developed HFpEF, 47 developed HFrEF, and 15 developed unclassified heart failure. In the multivariate regression model, IL-2 was associated with new-onset HFpEF (OR, 1.00058; 95% confidence interval, 1.00014 to 1.00102, p = 0.009) but not new-onset HFrEF. In multivariate analysis, MMP3, large LDL-C, and medium HDL-C were not associated with HFpEF or HFrEF.

Conclusion

These findings portend IL-2 as an important component of suboptimal inflammation in the pathogenesis of HFpEF.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02656-z.

Ca2+ mishandling in heart failure: Potential targets

Ca²⁺ mishandling is a common feature in several cardiovascular diseases such as heart failure (HF). In many cases, impairment of key players in intracellular Ca²⁺ homeostasis has been identified as the underlying mechanism of cardiac dysfunction and cardiac arrhythmias associated with HF. In this review, we summarize primary novel findings related to Ca²⁺ mishandling in HF progression. HF research has increasingly focused on the identification of new targets and the contribution of their role in Ca²⁺ handling to the progression of the disease. Recent research studies have identified potential targets in three major emerging areas implicated in regulation of Ca²⁺ handling: the innate immune system, bone metabolism factors and post-translational modification of key proteins involved in regulation of Ca²⁺ handling. Here, we describe their possible contributions to the progression of HF.

Relation between Cardiac Injury and Elevated Levels of Inflammatory Biomarkers in Patients with Severe COVID-19

Background: Since early December 2019, coronavirus disease 2019 (COVID-19) has emerged as a global pandemic and public health crisis. This study aims to explore the relationship between cardiac injury and inflammatory biomarkers in patients with severe COVID-19.Methods: We collected data on 91 patients with a confirmed diagnosis of severe COVID-19 from February 8 to March 31, 2020. Demographic characteristics, clinical data, and in-hospital outcomes were compared. The relationship between cardiac injury and inflammatory biomarkers was analyzed. Logistic regression was used to explore the independent risk factors for cardiac injury.Results: The mean age of all patients was 61 years±14 years. About half of the patients were male. Hypertension and coronary heart disease were more common in the cardiac injury group. The levels of inflammatory biomarkers in patients who experienced cardiac injury were generally higher than the levels of those without cardiac injury, including interleukin-6, interleukin-2 receptor (IL-2R), procalcitonin, and high-sensitivity C-reactive protein. There were positive correlations between the levels of high-sensitivity troponin I and N-terminal prohormone of brain natriuretic peptide and the levels of inflammatory biomarkers. Logistic regression shows that IL-2R (odds ratio 1.001, 95% confidence interval 1.000‐1.002, P=0.045) and comorbidities (odds ratio 4.909, 95% confidence interval 1.231‐19.579, P=0.024) are independent risk factors for cardiac injury in patients with severe COVID-19.Conclusion: High levels of inflammatory biomarkers are associated with higher risk of cardiac injury in patients with severe COVID-19. IL-2R and comorbidities are predictors of cardiac injury.

Association of soluble interleukin-2 receptor α and tumour necrosis factor receptor 1 with heart failure: The Multi-Ethnic Study of Atherosclerosis

Aims

Soluble tumour necrosis factor‐α receptor 1 (sTNF‐αR1) and interleukin‐2 receptor α (sIL‐2Rα) predict incident heart failure (HF) in the elderly population. However, the association of these biomarkers with HF in a multi‐ethnic asymptomatic population is unclear. We aimed to investigate the association of sTNF‐αR1 and sIL‐2Rα with incident HF in a multi‐ethnic population of middle age and older participants.

Methods and results

The multi‐ethnic study of atherosclerosis is a prospective population‐based study of 6814 participants aged 45–84 years who were free of clinical cardiovascular disease at enrolment. We included 2869 participants with available sTNF‐αR1 or sIL‐2Rα level measurement at baseline multi‐ethnic study of atherosclerosis exam (2000–2002). We used Cox proportional‐hazards model to investigate the association between sTNF‐αR1 and sIL‐2Rα with incident HF after adjusting for traditional cardiovascular risk factors and coronary artery calcium score measured by cardiac computed tomography. Among the included participants, the mean (standard deviation) age was 61.6 (10.2) years and 46.7% were men. The median (interquartile range) sTNF‐αR1 and sIL‐2Rα were 1293 (1107–1547) and 901 (727–1154) pg/mL. During a median follow‐up of 14.2 (interquartile range: 11.7–14.8) years, 130 participants developed HF. In multivariable analysis, the hazard ratio (95% confidence interval, P value) of incident HF for each standard deviation increment of log‐transformed sTNF‐αR1 and sIL‐2Rα was 1.43 (1.21–1.7, P ≤ 0.001) and 1.26 (1.04–1.53, P = 0.02), respectively. Excluding participants with interim coronary heart disease, we found a statistically significant association between sTNF‐αR1 and HF with hazard ratio of 1.39 (95% confidence interval: 1.11 to 1.74, P = 0.005) and sIL‐2Rα and HF showing a hazard ratio of 1.39 (95% confidence interval: 1.09 to 1.76, P = 0.007).

Conclusions

sTNF‐αR1 and sIL‐2Rα are associated with a higher risk of incident HF in a multi‐ethnic cohort without a previous history of cardiovascular disease.