Circulating S100A12 Levels Are Associated with Progression of Abdominal Aortic Calcification in Hemodialysis Patients

Increased serum S100A12 levels are associated with higher risk of acute heart failure in patients with type 2 diabetes

AIMS

The hyperglycaemic stress induces the release of inflammatory proteins such as S100A12, one of the endogenous ligands of the receptors for advanced glycation end products (RAGE). Chronic activation of RAGE has multiple deleterious effects in target tissues such as the heart and the vessels by promoting oxidative stress, inflammation by the release of cytokines, macrophages infiltration, and vascular cell migration and proliferation, causing ultimately endothelial cell and cardiomyocyte dysfunction. The aim of our study was to investigate the prognostic value of circulating S100A12 beyond established cardiovascular risk factors (CVRF) for heart failure (HF) and major adverse cardiovascular events (MACE) in a cohort of patients with type 2 diabetes.

METHODS AND RESULTS

Serum S100A12 concentrations were measured at baseline in 1345 type 2 diabetes patients (58% men, 64 ± 11 years) recruited in the SURDIAGENE prospective cohort. Endpoints were the occurrence of acute HF requiring hospitalization (HHF) and MACE. We used a proportional hazard model adjusted for established CVRF (age, sex, duration of diabetes, estimated glomerular filtration rate, albumin/creatinine ratio, history of coronary artery disease) and serum S100A12. During the median follow-up of 84 months, 210 (16%) and 505 (38%) patients developed HHF and MACE, respectively. Baseline serum S100A12 concentrations were associated with an increased risk of HHF [hazard ratio (HR) (95% confidence interval) 1.28 (1.01-1.62)], but not MACE [1.04 (0.90-1.20)]. After adjustment for CVRF, S100A12 concentrations remained significantly associated with an increased risk of HHF [1.29 (1.01-1.65)]. In a sub-analysis, patients with high probability of pre-existing HF [N terminal pro brain natriuretic peptide (NT-proBNP) >1000 pg/mL, n = 87] were excluded. In the remaining 1258 patients, the association of serum S100A12 with the risk of HHF tended to be more pronounced [1.39 (1.06-1.83)]. When including the gold standard HF marker NT-proBNP in the model, the prognostic value of S100A12 for HHF did not reach significance. Youden method performed at 7 years for HHF prediction yielded an optimal cut-off for S100A12 concentration of 49 ng/mL (sensitivity 53.3, specificity 52.2). Compared with those with S100A12 ≤ 49 ng/mL, patients with S100A12 > 49 ng/mL had a significantly increased risk of HHF in the univariate model [HR = 1.58 (1.19-2.09), P = 0.0015] but also in the multivariate model [HR = 1.63 (1.23-2.16), P = 0.0008]. After addition of NT-proBNP to the multivariate model, S100A12 > 49 ng/mL remained associated with an increased risk of HHF [HR = 1.42 (1.07-1.90), P = 0.0160]. However, the addition of S100A12 categories on top of multivariate model enriched by NT-pro BNP did not improve the ability of the model to predict HHF (relative integrated discrimination improvement = 1.9%, P = 0.1500).

CONCLUSIONS

In patients with type 2 diabetes, increased serum S100A12 concentration is independently associated with risk of HHF, but not with risk of MACE. Compared with NT-proBNP, the potential clinical interest of S100A12 for the prediction of HF events remains limited. However, S100A12 could be a candidate for a multimarker approach for HF risk assessment in diabetic patients.

The role of soluble receptor for advanced glycation end-products (sRAGE) in the general population and patients with diabetes mellitus with a focus on renal function and overall outcome

Isoforms of the receptor for advanced glycation end-product (RAGE) protein, which lack the transmembrane and the signaling (soluble RAGE or sRAGE) domains are hypothesized to counteract the detrimental action of the full-length receptor by acting as a decoy, and they provide a potential tool to treat RAGE-associated diseases. Multiple studies have explored the relationship between sRAGE and endogenous secretory RAGE and its polymorphism and obesity, metabolic syndrome, atherosclerosis, kidney function, and increased mortality in the general population. In addition, sRAGE may be a key player in the pathogenesis of diabetes mellitus and its microvascular (e.g. kidney disease) as well as macrovascular (e.g. cardiovascular disease) complications. In this review, we focus on the role of sRAGE as a biomarker in these specific areas. As there is a lack of an underlying unifying hypothesis about how sRAGE changes according to the disease condition or risk factor, there is a call to incorporate all three players of the AGE-RAGE axis into a new universal biomarker/risk marker: (AGE + RAGE)/sRAGE. However, the measurement of RAGE in humans is not practical as it is a cell-bound receptor for which tissue is required for analysis. A high AGE/sRAGE ratio may be a valuable alternative and practical universal biomarker/risk marker for diseases associated with the AGE-RAGE axis, irrespective of low or high serum sRAGE concentrations.

The predictive value of serum galectin 3 for abdominal aortic calcification in maintenance hemodialysis patients: A prospective cohort study

INTRODUCTION

Heterotopic vascular calcification is a common complication of maintenance hemodialysis (MHD) patients. Galectin 3 (Gal-3) has been reported to be associated with cardiovascular calcification. The current study aims to explore the potential predictive value of serum Gal-3 for severe abdominal aortic calcification (AAC) and AAC progression in MHD patients.

METHODS

A prospective cohort who underwent hemodialysis during July 2014 at the Blood Purification Center of Ruijin Hospital were followed up for 3 years. Two AAC assessments were performed: one at baseline and one after the 3-year follow-up period. Serum Gal-3 was detected with quantitative ELISA kits. SPSS 23.0 and MedCalc 11.4.2.0 were used to analyze the data.

FINDINGS

One hundred and fifty-two patients were recruited. Approximately 59.9% were male, the median age was 60 (50-67) years. Logistic regression analysis indicated that serum Gal-3 was an independent risk factor for both follow-up severe AAC and AAC progression. Receiver operating characteristic (ROC) curve analysis revealed significant prognostic value of serum Gal-3 for predicting severe AAC and AAC progression within 3 years.

DISCUSSION

We found serum Gal-3 is correlated to vascular calcification in ESRD patients. Gal-3 may be a potential biomarker of vascular calcification for MHD patients.

Comparison of different calcium supplementation methods in patients with osteoporosis

The aim of the present study was to explore the clinical efficacy and safety of different methods of calcium supplementation in osteoporosis (OP). Patients with OP were divided into four groups, including the control, oral calcium supplementation, intravenous calcium supplementation and combined calcium supplementation groups. The duration of the calcium supplementation was 3-6 years. Medical records were collected and examined along with demographic data, the incidence of certain diseases and adverse reactions. All subjects in the three treatment groups exhibited statistically significant reductions in alkaline phosphatase (ALP) levels, visual analog score (VAS) and Oswestry Disability Index (ODI) compared with the respective pre-treatment values. Furthermore, compared with prior to treatment, the lumbar and hip bone mineral density (BMD) of patients receiving intravenous calcium supplementation was significantly increased. In addition, after treatment, the lumbar and hip BMD was significantly increased, whereas ALP levels, VAS and ODI were significantly decreased in the oral calcium supplementation group compared with the control group. Also, compared with the control and oral calcium supplementation groups, the BMD was significantly increased, whereas ALP, VAS, ODI, the rate of infection and tooth loss, the incidence of fragility fractures, joint replacement surgery, arrhythmia, lumbar disc herniation and cerebral infarction were significantly decreased in the two groups treated with intravenous calcium supplementation. The results of the present study may enable a better understanding of the effectiveness and safety of the different methods for supplementing calcium in OP.

S100/RAGE-Mediated Inflammation and Modified Cholesterol Lipoproteins as Mediators of Osteoblastic Differentiation of Vascular Smooth Muscle Cells

Arterial calcification is a feature of atherosclerosis and shares many risk factors including diabetes, dyslipidemia, chronic kidney disease, hypertension, and age. Although there is overlap in risk factors, anti-atherosclerotic therapies, including statins, fail to reduce arterial, and aortic valve calcifications. This suggests that low density lipoprotein (LDL) may not be the main driver for aortic valve disease and arterial calcification. This review focuses on modified LDLs and their role in mediating foam cell formation in smooth muscle cells (SMCs), with special emphasis on enzyme modified non-oxidized LDL (ELDL). In vivo, ELDL represents one of the many forms of modified LDLs present in the atherosclerotic vessel. Phenotypic changes of macrophages and SMCs brought about by the uptake of modified LDLs overlap significantly in an atherosclerotic milieu, making it practically impossible to differentiate between the effects from oxidized LDL, ELDL, and other LDL modification. By studying in vitro-generated modifications of LDL, we were able to demonstrate marked differences in the transcriptome of human coronary artery SMCs (HCASMCs) upon uptake of ELDL, OxLDL, and native LDL, indicating that specific modifications of LDL in atherosclerotic plaques may determine the biology and functional consequences in vasculature. Enzyme-modified non-oxidized LDL (ELDL) induces calcification of SMCs and this is associated with reduced mRNA levels for genes protective for calcification (ENPP1, MGP) and upregulation of osteoblastic genes. A second focus of this review is on the synergy between hyperlipidemia and accelerated calcification In vivo in a mouse models with transgenic expression of human S100A12. We summarize mechanisms of S100A12/RAGE mediated vascular inflammation promoting vascular and valve calcification in vivo.

Role of the Soluble Receptor for Advanced Glycation End Products (sRAGE) as a Prognostic Factor for Mortality in Hemodialysis and Peritoneal Dialysis Patients

End-stage renal disease patients on dialysis (CKD-G5D) have a high mortality rate due to cardiovascular diseases (CVD). In these patients, inflammation, oxidative stress, and uremia increase the production of glycation products (AGEs) which in turn accelerate CVD onset and progression. Recently, attention has been given to the soluble receptor for AGEs (sRAGE) as a marker of inflammation, oxidative stress, atherosclerosis, and heart failure in CKD-G5D. However, its association with patient outcomes is still under debate. Our aim is to explore whether sRAGE may be a predictor of mortality in CKD-G5D. We studied 123 CKD-G5D for 24 months. Of these patients, 56 were on hemodialysis (HD) and 67 on peritoneal dialysis (PD). Demographic, anthropometric, biochemical, and clinical data were recorded. sRAGE was quantified by enzyme-linked immunosorbent assay. sRAGE was a predictor of mortality at 2-year follow-up. Each increase of 100 pg/mL in sRAGE levels was associated with an approximately 7% increased risk of mortality. Furthermore, in the entire study group, as well as in PD and HD patient subgroups, sRAGE was positively correlated with brain natriuretic peptide (BNP) levels. Mortality rates as well as sRAGE levels in patients who died did not differ between PD and HD patients. In conclusion, the positive association observed with BNP levels suggests a role for sRAGE as a prognostic factor for mortality in CKD-G5D patients displaying an active process of cardiac remodeling.

Critical Appraisal of Advanced Glycation End Products (AGEs) and Circulating Soluble Receptors for Advanced Glycation End Products (sRAGE) as a Predictive Biomarkers for Cardiovascular Disease in Hemodialysis Patients

The interaction of advanced glycation end products (AGE) and their receptors promote vascular complications of diabetes in hemodialysis (HD) patients. The soluble form of the receptor for the advanced glycation end-products (sRAGE) has been studied as a vascular biomarker in various diseases with controversial results. Our aim was to evaluate the association of the serum levels of the AGEs and their receptor sRAGE with cardiovascular disease (CVD) and the cardiovascular risk factors among HD patients. There were 130 HD patients and 80 age and gender matched control subjects were involved; 31.5% of the HD group were diabetic, which was an underlying cause of renal impairment; 36.1% had CVD, which was comprising 44.7% of diabetics and 55.3% of non-diabetic patients. The AGEs and sRAGE were assessed by enzyme linked immunosorbent assay (ELISA). In addition, the lipid profile, glycemic indices, pre-dialysis renal function tests, and hemoglobin % (Hb) were evaluated. The results show that the circulating AGEs and sRAGE levels were significantly higher in the HD patients. Those with underlying diabetes displayed higher sRAGE levels, which were positively correlated with hyperglycemia, HbA1C, and total cholesterol (TC). The HD patients with an increased serum sRAGE exhibited more cardiovascular risk factors (hypercholesterolemia and anemia) with a high prevalence of CVD. Using a linear regression analysis, we found a significant association of sRAGE with CVD and TC among HD patients, regardless of whether associating diabetes was an underlying cause of renal impairment. Overall, the HD patients displayed significantly higher serum AGEs with a concomitant increase in the circulating sRAGE levels, mainly in the diabetic HD, which were significantly associated with the CVD (independent predictors) and CV risk factors (hypercholesterolemia), mainly sRAGEs, regardless of the underlying diabetes mellitus. This highlights the prognostic role of AGEs and sRAGE in HD patients regardless of underlying cause in order to predict the risk for CVD.

Diagnostic Potential of Evaluation of SDF-1α and sRAGE Levels in Threatened Premature Labor

Preterm birth remains the most prevalent cause of neonatal morbidity. This study aimed to evaluate the diagnostic value of SDF-1α, resistin, secretory RAGE (sRAGE), and endogenous secretory RAGE (esRAGE) in preterm labor. A total of 211 pregnant women participated in the study. Group A contained 72 women between 22 and 36 weeks of gestation, with premature labor, who finally had preterm birth. Group B contained 66 women in labor between 37 and 41 weeks of gestation. Women in group A had lower SDF-1α and sRAGE levels than those in group B. Moreover, in group A, SDF-1α and sRAGE levels were correlated with the latency period from the occurrence of premature labor symptoms until delivery. Sensitivity and specificity of studied parameters for prediction of preterm birth were 95% and 40% for SDF-1α and 51.3% and 93.5% for sRAGE, respectively. The prognostic value of plasma SDF-1α and sRAGE levels was comparable with that of cervical length ultrasound measurement and serum C-reactive protein levels. We conclude that SDF-1α and sRAGE appear to play a major role in the diagnosis of preterm birth and its evaluation could be convenient and useful for predicting preterm birth.