The Relationship between Plasma Soluble Receptor for Advanced Glycation End Products and Coronary Artery Disease

Soluble receptor for advanced glycation end products and its role in cardiovascular risk assessment in hyperglycemia - A study in North India

Introduction

Advanced glycation end products (AGEs) and their cellular receptors (RAGEs) play an important role in the pathogenesis of type 2 diabetes mellitus and its progression to cardiovascular disease (CVD). A marker of the AGE-RAGE axis, soluble RAGE (sRAGE), was examined in this study in various glycemic states as well as in low- and high-CVD-risk patients.

Methods

In this cross-sectional study, 25 adults were recruited into each of the "Normoglycemic", "Prediabetic", and "Diabetic" groups based on American Diabetes Association 2019 HbA1c% level criteria. Using online American Heart Association Atherosclerotic CVD (AHA ASCVD) risk calculator and guidelines, patients were classified into "Low" and "High" risk categories. Serum sRAGE was assayed using sandwich ELISA technology. Serum markers necessary for calculation of homeostatic model assessment for insulin resistance (HOMA-IR) and atherogenic index of plasma (AIP) were spectrophotometrically estimated. Carotid intima-media thickness (CIMT) was analyzed using B-mode carotid ultrasonography.

Results

Mann-Whitney U analysis showed that sRAGE, AIP, HOMA-IR, CIMT, and %10-year CVD risk values were significantly different in the two ASCVD risk categories. Spearman test showed a significant correlation between sRAGE and other markers. ROC curve analysis demonstrated a higher area under the curve for sRAGE than other known parameters to differentiate between ASCVD risk categories. Finally, odds ratio analysis showed that sRAGE had higher odds of detecting high CVD risk than AIP or CIMT.

Conclusions

Our study has demonstrated the possible role of sRAGE in CVD development and suggests that they may serve as screening markers for future CVD risk.

Recent Trends in Advanced Glycation End Products in Foods: Formation, Toxicity, and Innovative Strategies for Extraction, Detection, and Inhibition

Advanced glycation end products (AGEs) are produced in foods during their thermal treatment through routes like the Maillard reaction. They have been linked to various health issues such as diabetes, neurodegenerative disorders, and cardiovascular diseases. There are multiple pathways through which AGEs can form in foods and the body. Therefore, this review work aims to explore multiple formation pathways of AGEs to gain insights into their generation mechanisms. Furthermore, this review work has analyzed the recent trends in the detection and inhibition of AGEs in food matrices. It can be highlighted, based on the surveyed literature, that UHPLC-Orbitrap-Q-Exactive-MS and UPLC-ESI-MS/MS can produce highly sensitive results with a low limit of detection levels for AGEs in food matrices. Moreover, various works on inhibitory agents like spices, herbs, fruits, vegetables, hydrocolloids, plasma-activated water, and probiotic bacteria were assessed for their capacity to suppress the formation of AGEs in food products and simulation models. Overall, it is essential to decrease the occurrence of AGEs in food products, and future scope might include studying the interaction of macromolecular components in food products to minimize the production of AGEs without sacrificing the organoleptic qualities of processed foods.

Usefulness of Serum Testosterone Concentration and Skin Autofluorescence as Coronary Risk Markers in Male Patients With Type 2 Diabetes Mellitus

Background

No studies have reported simultaneous evaluation of the two coronary risk markers of testosterone and skin autofluorescence (SAF) as a marker of advanced glycation end products in patients with type 2 diabetes mellitus (T2DM) at present. This study aimed to clarify the clinical significance of both indicators as risk markers of coronary artery disease (CAD), including the association and background factors between testosterone and SAF in male patients with T2DM.

Methods

This study enrolled 162 male patients with T2DM (CAD: n = 35). Testosterone was evaluated by serum total testosterone concentration (T-T). Various analyses related to T-T and SAF as coronary risk markers were performed.

Results

T-T was significantly lower, and SAF was significantly higher in patients with CAD than in patients with non-CAD. A significant negative correlation was found between T-T and SAF (r = -0.45, P < 0.001), and the correlation was stronger in patients with CAD than in patients with non-CAD (non-CAD, r = -0.27, P = 0.003; CAD, r = -0.51, P < 0.001). However, both T-T and SAF had significant associations with triglyceride-glucose index as an insulin resistance marker and cardio-ankle vascular index as an arterial function marker. Multiple regression analysis revealed that both T-T and SAF were selected as independent variables to the presence of CAD as a dependent variable. However, the odds ratio increased due to the merger of two coronary risk markers, low T-T and high SAF (odds ratio: one risk marker: 3.24, 95% confidence interval: 1.01 - 10.50, P = 0.045; two risk markers: 13.22, 95% confidence interval: 3.41 - 39.92, P < 0.001).

Conclusions

The results of this cross-sectional study indicate that T-T and SAF are closely related in CAD patients with T2DM. It also shows that insulin resistance and arterial dysfunction are in the background of both indicators. Additionally, not only are both indicators independent coronary risk markers, but the overlap of both indicators increases their weight as coronary risk markers.

A pilot study of S100A4, S100A8/A9, and S100A12 in dilated cardiomyopathy: novel biomarkers for diagnosis or prognosis?

AIMS

Circulating biomarkers can provide important information for the diagnosis and prognosis of dilated cardiomyopathy (DCM). We explored novel biomarkers for the diagnosis and prognosis of DCM to improve clinical decision-making.

METHODS AND RESULTS

A total of 238 DCM patients and 65 control were consecutively enrolled at Zhongshan Hospital between January 2017 and January 2019. In the screening set, four DCM patients and four controls underwent measurements of serum proteomic analysis. Seventy-six differentially expressed circulating proteins were screened by data-independent acquisition proteomics, and three of these proteins (S100A4, S100A8/A9, and S100A12) were validated by multiple-reaction monitoring-mass spectrometry. In the validation set, subsequently, a total of 234 DCM patients and 61 control subjects were evaluated by enzyme-linked immunosorbent assay. Circulating S100A4, S100A8/A9, and S100A12 were significantly increased in DCM patients (P < 0.001). These three proteins were significant positively correlated with other parameters, such as Lg (NT-proBNP), IL-1β, TGF-β, CRP, left ventricular end-diastolic diameter, and left ventricular end-systolic diameter, whereas they were negatively correlated with left ventricular ejection fraction, respectively (P < 0.05). The receiver operator characteristic curve showed the combination of S100A4, S100A8/A9, and S100A12 [area under curve (AUC) 0.88, 95% confidence interval (CI) 0.84-0.93] was better than single S100A4 (AUC 0.74, 95% CI 0.68-0.81), S100A8/A9 (AUC 0.82, 95% CI 0.77-0.88), or S100A12 (AUC 0.80, 95% CI 0.72-0.88) in the diagnosis of DCM (P < 0.01). After a median follow-up period of 33.5 months, 110 patients (47.01%) experienced major adverse cardiac events (MACEs), including 46 who had cardiac deaths and 64 who had heart failure rehospitalizations. Kaplan-Meier analysis indicated that the DCM patients with ≥75th percentile level of S100A4 had a significantly higher incidence of MACEs than those with <75th percentile level of S100A4 (61.40% vs. 42.37%, P < 0.05). There were no significant differences of MACE rate among DCM patients with different concentrations of S100A8/A9 and S100A12 (P > 0.05). Cox proportional hazards regression analysis revealed that S100A4 [≥75th percentile vs. <75th percentile: hazard ratio (HR) 1.65; 95% CI 1.11-2.45] remained significant independent predictors for MACEs (P < 0.05); however, S100A8/A9 and S100A12 were not independent factors for predicting MACE (P ≥ 0.05).

CONCLUSIONS

S100A4, S100A8/A9, and S100A12 may be additional diagnostic tools for human DCM recognition, and the combination of these three indicators helped to improve the accuracy of a single index to diagnose DCM. Additionally, S100A4 was identified as a significant predictor of prognosis in patients with DCM.

RAGE/DIAPH1 and atherosclerosis through an evolving lens: Viewing the cell from the "Inside - Out"

BACKGROUND AND AIMS

In hyperglycemia, inflammation, oxidative stress and aging, Damage Associated Molecular Patterns (DAMPs) accumulate in conditions such as atherosclerosis. Binding of DAMPs to receptors such as the receptor for advanced glycation end products (RAGE) activates signal transduction cascades that contribute to cellular stress. The cytoplasmic domain (tail) of RAGE (ctRAGE) binds to the formin Diaphanous1 (DIAPH1), which is important for RAGE signaling. This Review will detail the evidence linking the RAGE/DIAPH1 signaling pathway to atherosclerosis and envisages future therapeutic opportunities from the "inside-out" point of view in affected cells.

METHODS

PubMed was searched using a variety of search terms, including "receptor for advanced glycation end products" along with various combinations including "and atherosclerosis," "soluble RAGE and atherosclerosis," "statins and RAGE," "PPAR and RAGE" and "SGLT2 inhibitor and RAGE."

RESULTS

In non-diabetic and diabetic mice, antagonism or global deletion of Ager (the gene encoding RAGE) retards progression and accelerates regression of atherosclerosis. Global deletion of Diaph1 in mice devoid of the low density lipoprotein receptor (Ldlr) significantly attenuates atherosclerosis; mice devoid of both Diaph1 and Ldlr display significantly lower plasma and liver concentrations of cholesterol and triglyceride compared to mice devoid of Ldlr. Associations between RAGE pathway and human atherosclerosis have been identified based on relationships between plasma/serum concentrations of RAGE ligands, soluble RAGEs and atherosclerosis.

CONCLUSIONS

Efforts to target RAGE/DIAPH1 signaling through a small molecule antagonist therapeutic strategy hold promise to quell accelerated atherosclerosis in diabetes and in other forms of cardiovascular disease.

The role of sRAGE in cardiovascular diseases

Advanced glycation end products (AGEs), by-products of glucose metabolism, have been linked to the emergence of cardiovascular disorders (CVD). AGEs can cause tissue damage in four different ways: (1) by altering protein function, (2) by crosslinking proteins, which makes tissue stiffer, (3) by causing the generation of free radicals, and (4) by activating an inflammatory response after binding particular AGE receptors, such as the receptor for advanced glycation end products (RAGE). It is suggested that the soluble form of RAGE (sRAGE) blocks ligand-mediated pro-inflammatory and oxidant activities by serving as a decoy. Therefore, several studies have investigated the possible anti-inflammatory and anti-oxidant characteristics of sRAGE, which may help lower the risk of CVD. According to the results of various studies, the relationship between circulating sRAGE, cRAGE, and esRAGE and CVD is inconsistent. To establish the potential function of sRAGE as a therapeutic target in the treatment of cardiovascular illnesses, additional studies are required to better understand the relationship between sRAGE and CVD. In this review, we explored the potential function of sRAGE in different CVD, highlighting unanswered concerns and outlining the possibilities for further investigation.

Human Plasma Transcriptome Implicates Dysregulated S100A12 Expression: A Strong, Early-Stage Prognostic Factor in ST-Segment Elevated Myocardial Infarction: Bioinformatics Analysis and Experimental Verification

The ability of blood transcriptome analysis to identify dysregulated pathways and outcome-related genes following myocardial infarction remains unknown. Two gene expression datasets (GSE60993 and GSE61144) were downloaded from Gene Expression Omnibus (GEO) Datasets to identify altered plasma transcriptomes in patients with ST-segment elevated myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. GEO2R, Gene Ontology/Kyoto Encyclopedia of Genes and Genomes annotations, protein-protein interaction analysis, etc., were adopted to determine functional roles and regulatory networks of differentially expressed genes (DEGs). Dysregulated expressomes were verified at transcriptional and translational levels by analyzing the GSE49925 dataset and our own samples, respectively. A total of 91 DEGs were identified in the discovery phase, consisting of 15 downregulated genes and 76 upregulated genes. Two hub modules consisting of 12 hub genes were identified. In the verification phase, six of the 12 hub genes exhibited the same variation patterns at the transcriptional level in the GSE49925 dataset. Among them, S100A12 was shown to have the best discriminative performance for predicting in-hospital mortality and to be the only independent predictor of death during follow-up. Validation of 223 samples from our center showed that S100A12 protein level in plasma was significantly lower among patients who survived to discharge, but it was not an independent predictor of survival to discharge or recurrent major adverse cardiovascular events after discharge. In conclusion, the dysregulated expression of plasma S100A12 at the transcriptional level is a robust early prognostic factor in patients with STEMI, while the discrimination power of the protein level in plasma needs to be further verified by large-scale, prospective, international, multicenter studies.

Profilin-1 is involved in macroangiopathy induced by advanced glycation end products via vascular remodeling and inflammation

BACKGROUND

The accumulation of advanced glycation end products (AGEs) have been implicated in the development and progression of diabetic vasculopathy. However, the role of profilin-1 as a multifunctional actin-binding protein in AGEs-induced atherosclerosis (AS) is largely unknown.

AIM

To explore the potential role of profilin-1 in the pathogenesis of AS induced by AGEs, particularly in relation to the Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) signaling pathway.

METHODS

Eighty-nine individuals undergoing coronary angiography were enrolled in the study. Plasma cytokine levels were detected using ELISA kits. Rat aortic vascular smooth muscle cells (RASMCs) were incubated with different compounds for different times. Cell proliferation was determined by performing the MTT assay and EdU staining. An AGEs-induced vascular remodeling model was established in rats and histological and immunohistochemical analyses were performed. The mRNA and protein levels were detected using real-time PCR and Western blot analysis, respectively. In vivo, shRNA transfection was performed to verify the role of profilin-1 in AGEs-induced proatherogenic mediator release and aortic remodeling. Statistical analyses were performed using SPSS 22.0 software.

RESULTS

Compared with the control group, plasma levels of profilin-1 and receptor for AGEs (RAGE) were significantly increased in patients with coronary artery disease, especially in those complicated with diabetes mellitus (P < 0.01). The levels of profilin-1 were positively correlated with the levels of RAGE (P < 0.01); additionally, the levels of both molecules were positively associated with the degree of coronary artery stenosis (P < 0.01). In vivo, tail vein injections of AGEs induced the release of proatherogenic mediators, such as asymmetric dimethylarginine, intercellular adhesion molecule-1, and the N-terminus of procollagen III peptide, concomitant with apparent aortic morphological changes and significantly upregulated expression of the profilin-1 mRNA and protein in the thoracic aorta (P < 0.05 or P < 0.01). Downregulation of profilin-1 expression with an shRNA significantly attenuated AGEs-induced proatherogenic mediator release (P < 0.05) and aortic remodeling. In vitro, incubation of vascular smooth muscle cells (VSMCs) with AGEs significantly promoted cell proliferation and upregulated the expression of the profilin-1 mRNA and protein (P < 0.05). AGEs (200 μg/mL, 24 h) significantly upregulated the expression of the STAT3 mRNA and protein and JAK2 protein, which was blocked by a JAK2 inhibitor (T3042-1) and/or STAT3 inhibitor (T6308-1) (P < 0.05). In addition, pretreatment with T3042-1 or T6308-1 significantly inhibited AGEs-induced RASMC proliferation (P < 0.05).

CONCLUSION

AGEs induce proatherogenic events such as VSMC proliferation, proatherogenic mediator release, and vascular remodeling, changes that can be attenuated by silencing profilin-1 expression. These results suggest a crucial role for profilin-1 in AGEs-induced vasculopathy.

Accuracy of triggering receptor expressed on myeloid cells 1 in diagnosis and prognosis of acute myocardial infarction: a prospective cohort study

Background

Acute myocardial infarction (AMI) is one of the fatal cardiac emergencies. The detection of triggering receptor expressed on myeloid cells 1 (TREM1), a cell surface immunoglobulin that amplifies pro-inflammatory responses, screened by bioinformatics was shown to be significant in diagnosing and predicting the prognosis of AMI.

Methods

GSE66360, GSE61144 and GSE60993 were downloaded from the Gene Expression Omnibus (GEO) database to explore the differentially expressed genes (DEGs) between AMI and control groups using R software. A total of 147 patients in total were prospectively enrolled from October 2018 to June 2019 and divided into two groups, the normal group (n = 35) and the AMI group (n = 112). Plasma was collected from each patient at admission and all patients received 6-month follow-up care.

Results

According to bioinformatic analysis, TREM1 was an important DEG in patients with AMI. Compared with the normal group, TREM1 expression was markedly increased in the AMI group (p < 0.001). TREM1 expression was positively correlated with fasting plasma glucose (FPG), glycosylated hemoglobin (HbAC), and the number of lesion vessels, although it had no correlation with Gensini score. TREM1 expression in the triple-vessels group was significantly higher than that of the single-vessel group (p < 0.05). Multiple linear regression showed that UA and HbAC were two factors influencing TREM1 expression. The ROC curve showed that TREM1 had a diagnostic significance in AMI (p < 0.001), especially in AMI patients without diabetes. Cox regression showed increased TREM1 expression was closely associated with 6-month major adverse cardiac events (MACEs) (p < 0.001).

Conclusions

TREM1 is a potentially significant biomarker for the diagnosis of AMI and may be closely associated with the severity of coronary lesions and diabetes. TREM1 may also be helpful in predicting the 6-month MACEs after AMI.

Hyperactivated RAGE in Comorbidities as a Risk Factor for Severe COVID-19-The Role of RAGE-RAS Crosstalk

The receptor for advanced glycation-end products (RAGE) is a multiligand receptor with a role in inflammatory and pulmonary pathologies. Hyperactivation of RAGE by its ligands has been reported to sustain inflammation and oxidative stress in common comorbidities of severe COVID-19. RAGE is essential to the deleterious effects of the renin-angiotensin system (RAS), which participates in infection and multiorgan injury in COVID-19 patients. Thus, RAGE might be a major player in severe COVID-19, and appears to be a useful therapeutic molecular target in infections by SARS-CoV-2. The role of RAGE gene polymorphisms in predisposing patients to severe COVID-19 is discussed.&nbsp.

AGE-RAGE Stress and Coronary Artery Disease

Coronary artery atherosclerosis and atherosclerotic plaque rupture cause coronary artery disease (CAD). Advanced glycation end products (AGE) and its cell receptor RAGE, and soluble receptor (sRAGE) and endogenous secretory RAGE (esRAGE) may be involved in the development of atherosclerosis. AGE and its interaction with RAGE are atherogenic, while sRAGE and esRAGE have antiatherogenic effects. AGE-RAGE stress is a ratio of AGE/sRAGE. A high AGE-RAGE stress results in development and progression of CAD and vice-versa. AGE levels in serum and skin, AGE/sRAGE in patients with CAD, and expression of RAGE in animal model of atherosclerosis were higher, while serum levels of esRAGE were lower in patients with CAD compared with controls. Serum levels of sRAGE in CAD patients were contradictory, increased or decreased. This contradictory data may be due to type of patients used, because the sRAGE levels are elevated in diabetics and end-stage renal disease. AGE/sRAGE ratio is elevated in patients with reduced or elevated levels of serum sRAGE. It is to stress that AGE, RAGE, sRAGE, or esRAGE individually cannot serve as universal biomarker. AGE and sRAGE should be measured simultaneously to assess the AGE-RAGE stress. The treatment of CAD should be targeted at reduction in AGE levels, prevention of AGE formation, degradation of AGE in vivo, suppression of RAGE expression, blockade of RAGE, elevation of sRAGE, and use of antioxidants. In conclusion, AGE-RAGE stress would initiate the development and progression of atherosclerosis. Treatment modalities would prevent, regress, and slow the progression of CAD.