S100 proteins in atherosclerosis

Advances in the study of S100A9 in cardiovascular diseases

Cardiovascular disease (CVD) is a group of diseases that primarily affect the heart or blood vessels, with high disability and mortality rates, posing a serious threat to human health. The causative factors, pathogenesis, and characteristics of common CVD differ, but they all involve common pathological processes such as inflammation, oxidative stress, and fibrosis. S100A9 belongs to the S100 family of calcium-binding proteins, which are mainly secreted by myeloid cells and bind to the Toll-like receptor 4 and receptor for advanced glycation end products and is involved in regulating pathological processes such as inflammatory response, fibrosis, vascular calcification, and endothelial barrier function in CVD. The latest research has found that S100A9 is a key biomarker for diagnosing and predicting various CVD. Therefore, this article reviews the latest research progress on the diagnostic and predictive, and therapeutic value of S100A9 in inflammatory-related CVD such as atherosclerosis, myocardial infarction, and arterial aneurysm and summarizes its molecular mechanisms in the progression of CVD, aiming to explore new predictive methods and to identify potential intervention targets for CVD in clinical practice.

Single Cell High Dimensional Analysis of Human Peripheral Blood Mononuclear Cells Reveals Unique Intermediate Monocyte Subsets Associated with Sex Differences in Coronary Artery Disease

Monocytes are associated with human cardiovascular disease progression. Monocytes are segregated into three major subsets: classical (cMo), intermediate (iMo), and nonclassical (nMo). Recent studies have identified heterogeneity within each of these main monocyte classes, yet the extent to which these subsets contribute to heart disease progression is not known. Peripheral blood mononuclear cells (PBMC) were obtained from 61 human subjects within the Coronary Assessment of Virginia (CAVA) Cohort. Coronary atherosclerosis severity was quantified using the Gensini Score (GS). We employed high-dimensional single-cell transcriptome and protein methods to define how human monocytes differ in subjects with low to severe coronary artery disease. We analyzed 487 immune-related genes and 49 surface proteins at the single-cell level using Antibody-Seq (Ab-Seq). We identified six subsets of myeloid cells (cMo, iMo, nMo, plasmacytoid DC, classical DC, and DC3) at the single-cell level based on surface proteins, and we associated these subsets with coronary artery disease (CAD) incidence based on Gensini score (GS) in each subject. Only frequencies of iMo were associated with high CAD (GS > 32), adj.p = 0.024. Spearman correlation analysis with GS from each subject revealed a positive correlation with iMo frequencies (r = 0.314, p = 0.014) and further showed a robust sex-dependent positive correlation in female subjects (r = 0.663, p = 0.004). cMo frequencies did not correlate with CAD severity. Key gene pathways differed in iMo among low and high CAD subjects and between males and females. Further single-cell analysis of iMo revealed three iMo subsets in human PBMC, distinguished by the expression of HLA-DR, CXCR3, and CD206. We found that the frequency of immunoregulatory iMo_HLA-DR+CXCR3+CD206+ was associated with CAD severity (adj.p = 0.006). The immunoregulatory iMo subset positively correlated with GS in both females (r = 0.660, p = 0.004) and males (r = 0.315, p = 0.037). Cell interaction analyses identified strong interactions of iMo with CD4+ effector/memory T cells and Tregs from the same subjects. This study shows the importance of iMo in CAD progression and suggests that iMo may have important functional roles in modulating CAD risk, particularly among females.

Vascular calcification: from the perspective of crosstalk

Vascular calcification (VC) is highly correlated with cardiovascular disease morbidity and mortality, but anti-VC treatment remains an area to be tackled due to the ill-defined molecular mechanisms. Regardless of the type of VC, it does not depend on a single cell but involves multi-cells/organs to form a complex cellular communication network through the vascular microenvironment to participate in the occurrence and development of VC. Therefore, focusing only on the direct effect of pathological factors on vascular smooth muscle cells (VSMCs) tends to overlook the combined effect of other cells and VSMCs, including VSMCs-VSMCs, ECs-VMSCs, Macrophages-VSMCs, etc. Extracellular vesicles (EVs) are a collective term for tiny vesicles with a membrane structure that are actively secreted by cells, and almost all cells secrete EVs. EVs docked on the surface of receptor cells can directly mediate signal transduction or transfer their contents into the cell to elicit a functional response from the receptor cells. They have been proven to participate in the VC process and have also shown attractive therapeutic prospects. Based on the advantages of EVs and the ability to be detected in body fluids, they may become a novel therapeutic agent, drug delivery vehicle, diagnostic and prognostic biomarker, and potential therapeutic target in the future. This review focuses on the new insight into VC molecular mechanisms from the perspective of crosstalk, summarizes how multi-cells/organs interactions communicate via EVs to regulate VC and the emerging potential of EVs as therapeutic methods in VC. We also summarize preclinical experiments on crosstalk-based and the current state of clinical studies on VC-related measures.

Indole-3-carbinol mitigates oxidative stress and inhibits inflammation in rat cerebral ischemia/reperfusion model

Ischemia is a significant pathogenetic factor of stroke with very limited treatment options. The objective of our research was to evaluate the protective properties of indole-3-carbinol (I3C) and its effect on redox status parameters, inflammation, and apoptosis intensity in cerebral ischemia/reperfusion injury (CIRI) in rats. I3C administration to CIRI rats decreased levels of oxidative stress markers and improved aerobic metabolism compared to the animals with CIRI. A decrease in myeloperoxidase activity, proinflammatory cytokines mRNA levels, and expression of redox-sensitive factor Nuclear Factor-κB was observed in rats with CIRI that received I3C. I3C-treated rats with pathology showed decreased caspase activity and apoptosis-inducing factor expression, compared to the animals in the CIRI group. Obtained data indicate that I3C has a neuroprotective and anti-ischemic effect in CIRI that may be related to its antioxidant properties and ability to reduce the inflammatory response and apoptosis.

Interaction of S100A6 Protein with the Four-Helical Cytokines

S100 is a family of over 20 structurally homologous, but functionally diverse regulatory (calcium/zinc)-binding proteins of vertebrates. The involvement of S100 proteins in numerous vital (patho)physiological processes is mediated by their interaction with various (intra/extra)cellular protein partners, including cell surface receptors. Furthermore, recent studies have revealed the ability of specific S100 proteins to modulate cell signaling via direct interaction with cytokines. Previously, we revealed the binding of ca. 71% of the four-helical cytokines via the S100P protein, due to the presence in its molecule of a cytokine-binding site overlapping with the binding site for the S100P receptor. Here, we show that another S100 protein, S100A6 (that has a pairwise sequence identity with S100P of 35%), specifically binds numerous four-helical cytokines. We have studied the affinity of the recombinant forms of 35 human four-helical cytokines from all structural families of this fold to Ca2+-loaded recombinant human S100A6, using surface plasmon resonance spectroscopy. S100A6 recognizes 26 of the cytokines from all families of this fold, with equilibrium dissociation constants from 0.3 nM to 12 µM. Overall, S100A6 interacts with ca. 73% of the four-helical cytokines studied to date, with a selectivity equivalent to that for the S100P protein, with the differences limited to the binding of interleukin-2 and oncostatin M. The molecular docking study evidences the presence in the S100A6 molecule of a cytokine-binding site, analogous to that found in S100P. The findings argue the presence in some of the promiscuous members of the S100 family of a site specific to a wide range of four-helical cytokines. This unique feature of the S100 proteins potentially allows them to modulate the activity of the numerous four-helical cytokines in the disorders accompanied by an excessive release of the cytokines.

Differential Expression of Subsets of Genes Related to HDL Metabolism and Atherogenesis in the Peripheral Blood in Coronary Artery Disease

Differential expression of genes (DEGs) in coronary artery disease (CAD) and the association between transcript level and high-density lipoprotein cholesterol (HDL-C) were studied with 76 male patients with CAD and 63 control patients. The transcript level of genes related to HDL metabolism (24 genes) and atherosclerosis-prone (41 genes) in RNA isolated from peripheral blood mononuclear cells was measured by real-time RT-PCR. Twenty-eight DEGs were identified. The expression of cholesterol transporters, ALB, APOA1, and LCAT was down-regulated, while the expression of AMN, APOE, LDLR, LPL, PLTP, PRKACA, and CETP was up-regulated. The systemic inflammation in CAD is evidenced by the up-regulation of IL1B, TLR8, CXCL5, and TNFRSF1A. For the controls, TLR8 and SOAT1 were negative predictors of the HDL-C level. For CAD patients, PRKACG, PRKCQ, and SREBF1 were positive predictors, while PRKACB, LCAT, and S100A8 were negative predictors. For CAD patients, the efficiency of reverse cholesterol transport is 73-79%, and intracellular free cholesterol seems to accumulate at hyperalphalipoproteinemia. Both atheroprotective (via S100A8) and proatherogenic (via SREBF1, LCAT, PRKACG, PRKACB, and PRKCQ) associations of gene expression with HDL-C determine HDL functionality in CAD patients. The selected key genes and involved pathways may represent HDL-specific targets for the diagnosis and treatment of CAD and atherosclerosis.

EphrinB2 drives osteogenic fate of adult cardiac fibroblasts in a calcium influx dependent manner

Cardiac calcification is a crucial but underrecognized pathological process, greatly increasing the risk of cardiovascular diseases. Little is known about how cardiac fibroblasts, as a central mediator, facilitate abnormal mineralization. Erythropoietin-producing hepatoma interactor B2 (EphrinB2), previously identified as an angiogenic regulator, is involved in fibroblast activation, while its role in the osteogenic differentiation of cardiac fibroblasts is unknown. Bioinformatics analysis was conducted to characterize the expression of the Ephrin family in human calcified aortic valves and calcific mouse hearts. The effects of EphrinB2 on cardiac fibroblasts to adopt osteogenic fate was determined by gain- and loss-of-function. EphrinB2 mRNA level was downregulated in calcified aortic valves and mouse hearts. Knockdown of EphrinB2 attenuated mineral deposits in adult cardiac fibroblasts, whereas overexpression of EphrinB2 promoted their osteogenic differentiation. RNA sequencing data implied that Ca2+-related S100/receptor for advanced glycation end products (RAGE) signaling may mediate EphrinB2-induced mineralization in cardiac fibroblasts. Moreover, L-type calcium channel blockers inhibited osteogenic differentiation of cardiac fibroblasts, implying a critical role in Ca2+ influx. In conclusion, our data illustrated an unrecognized role of EphrinB2, which functions as a novel osteogenic regulator in the heart through Ca2+ signaling and could be a potential therapeutic target in cardiovascular calcification.NEW & NOTEWORTHY In this study, we observed that adult cardiac fibroblasts but not neonatal cardiac fibroblasts exhibit the ability of osteogenic differentiation. EphrinB2 promoted osteogenic differentiation of cardiac fibroblasts through activating Ca2+-related S100/RAGE signaling. Inhibition of Ca2+ influx using L-type calcium channel blockers inhibited EphrinB2-mediated calcification of cardiac fibroblasts. Our data implied an unrecognized role of EphrinB2 in regulating cardiac calcification though Ca2+-related signaling, suggesting a potential therapeutic target of cardiovascular calcification.

Bioinformatics analysis and identification of hub genes associated with female acute myocardial infarction patients by using weighted gene co-expression networks

To explore potential biomarkers of acute myocardial infarction (AMI) in females by using bioinformatics analysis. In this study, we explored potential biomarkers of AMI in females using bioinformatics analysis. We screened a total of 186 differentially expressed genes from the Gene Expression Omnibus. In the study, we found that weighted gene co-expression network analysis explored the co-expression network of genes and identified key modules. Simultaneously, we chose brown modules as key modules related to AMI. In this study, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis revealed that genes in the brown module were mainly enriched in "heparin" and 'complementation and coagulation cascade. Based on the protein-protein interaction network, we identified S100A9, mitogen-activated protein kinase (MAPK) 3, MAPK1, MMP3, interleukin (IL)-17A, and HSP90AB1 as hub gene sets. Whereas, polymerase chain reaction results showed that S100A9, MAPK3, MAPK1, MMP3, IL-17A, and HSP90AB1 were highly expressed compared with the control group. The IL-17 signaling pathway associated with an inflammatory response may be a potential biomarker and target for the treatment of women with myocardial infarction.

Integrated bioinformatics and machine-learning screening for immune-related genes in diagnosing non-alcoholic fatty liver disease with ischemic stroke and RRS1 pan-cancer analysis

Background

The occurrence of ischemic stroke (IS) is associated with nonalcoholic fatty liver disease (NAFLD). The cancer burden of NAFLD complicated by IS also warrants attention. This study aimed to identify candidate immune biomarkers linked to NAFLD and IS and analyze their association with cancer.

Methods

Two of each of the NAFLD and IS datasets were downloaded, differentially expressed genes (DEGs) were identified, and module genes were screened via weighted gene coexpression network analysis (WGCNA). Subsequently, utilizing machine learning (least absolute shrinkage and selection operator regression, random forest and support vector machine-recursive feature elimination) and immune cell infiltration analysis, immune-related candidate biomarkers for NAFLD with IS were determined. Simultaneously, a nomogram was established, the diagnostic efficacy was assessed, and the role of candidate biomarkers in cancer was ascertained through pan-cancer analyses.

Results

In this study, 117 and 98 DEGs were identified from the combined NAFLD and IS datasets, respectively, and 279 genes were obtained from the most significant modules of NAFLD. NAFLD module genes and IS DEGs were intersected to obtain nine genes, which were enriched in the inflammatory response and immune regulation. After overlapping the results of the three machine learning algorithms, six candidate genes were obtained, based on which a nomogram was constructed. The calibration curve demonstrated good accuracy, and the candidate genes had high diagnostic values. The genes were found to be related to the immune dysregulation of stroke, and RRS1 was strongly associated with the prognosis, immune cell infiltration, microsatellite instability (MSI), and tumor mutation burden (TMB).

Conclusion

Six common candidate immune-related genes (PTGS2, FCGR1A, MMP9, VNN3, S100A12, and RRS1) of NAFLD and IS were identified, and a nomogram for diagnosing NAFLD with IS was established. RRS1 may serve as a candidate gene for predicting the prognosis of patients with cancer who have NAFLD complicated by IS, which could aid in their diagnosis and treatment.

TJ-M2010-5 Attenuates Severe Myocardial Ischemia/Reperfusion Injury in Heart Transplantation by Inhibiting MyD88 Homodimerization In Vivo

Survival of transplanted hearts is often limited by cold ischemia time. Here, we assessed the effects of the small molecular compound TJ-M2010-5 on graft preservation. In a cardiac cold ischemia/reperfusion model, TJ-M2010-5 ameliorated myocardial ischemia/reperfusion injury (MIRI) in histidine-tryptophan-ketoglutarate (HTK) organ preservation solution. When applied in HTK solution and on donors/recipients respectively, TJ-M2010-5 exerted optimal effects when applied as an additive in the HTK solution. TJ-M2010-5-administered mice exhibited shorter rebeating time; higher beating score; stronger and more regular sinus heart rate; and amelioration of apoptosis, inflammatory reactions, and myocardial injury. Mechanistically, TJ-M2010-5 inhibited the expression of key molecules in the toll-like receptor (TLR) signaling pathway and affected downstream proteins by inhibiting myeloid differentiation factor 88 homodimerization, thereby decreasing myocardial injury. Thus, TJ-M2010-5 may exert protective effects against MIRI by blocking the TLR signaling pathway. Our findings may lead to novel approaches for organ preservation, thereby reducing organ abandonment and improving recipient prognosis. The role of the TLR signaling pathway in MIRI progress and operation procedure of the MIRI model in vivo are presented in a graphical abstract (Online Abstract Figure).

S100 Proteins in Fatty Liver Disease and Hepatocellular Carcinoma

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent and slow progressing hepatic pathology characterized by different stages of increasing severity which can ultimately give rise to the development of hepatocellular carcinoma (HCC). Besides drastic lifestyle changes, few drugs are effective to some extent alleviate NAFLD and HCC remains a poorly curable cancer. Among the deregulated molecular mechanisms promoting NAFLD and HCC, several members of the S100 proteins family appear to play an important role in the development of hepatic steatosis, non-alcoholic steatohepatitis (NASH) and HCC. Specific members of this Ca²⁺-binding protein family are indeed significantly overexpressed in either parenchymal or non-parenchymal liver cells, where they exert pleiotropic pathological functions driving NAFLD/NASH to severe stages and/or cancer development. The aberrant activity of S100 specific isoforms has also been reported to drive malignancy in liver cancers. Herein, we discuss the implication of several key members of this family, e.g., S100A4, S100A6, S100A8, S100A9 and S100A11, in NAFLD and HCC, with a particular focus on their intracellular versus extracellular functions in different hepatic cell types. Their clinical relevance as non-invasive diagnostic/prognostic biomarkers for the different stages of NAFLD and HCC, or their pharmacological targeting for therapeutic purpose, is further debated.

Inflammation and Oxidative Stress Role of S100A12 as a Potential Diagnostic and Therapeutic Biomarker in Acute Myocardial Infarction

Acute myocardial infarction (AMI) is one of the most serious cardiovascular diseases with high morbidity and mortality. Numerous studies have indicated that S100A12 may has an essential role in the occurrence and development of AMI, and in-depth studies are currently lacking. The purpose of this study is to investigate the effect of S100A12 on inflammation and oxidative stress and to determine its clinical applicability in AMI. Here, AMI datasets used to explore the expression pattern of S100A12 in AMI were derived from the Gene Expression Omnibus (GEO) database. The pooled standard average deviation (SMD) was calculated to further determine S100A12 expression. The overlapping differentially expressed genes (DEGs) contained in all included datasets were recognized by the GEO2R tool. Then, functional enrichment analyses, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, were carried out to determine the molecular function of overlapping DEGs. Gene set enrichment analysis (GSEA) was conducted to determine unrevealed mechanisms of S100A12. Summary receiver operating characteristic (SROC) curve analysis and receiver operating characteristic (ROC) curve analysis were carried out to identify the diagnostic capabilities of S100A12. Moreover, we screened miRNAs targeting S100A12 using three online databases (miRWalk, TargetScan, and miRDB). In addition, by comprehensively using enzyme-linked immunosorbent assay (ELISA), real-time quantitative PCR (RT-qPCR), Western blotting (WB) methods, etc., we used the AC16 cells to validate the expression and underlying mechanism of S100A12. In our study, five datasets related to AMI, GSE24519, GSE60993, GSE66360, GSE97320, and GSE48060 were included; 412 overlapping DEGs were identified. Protein-protein interaction (PPI) network and functional analyses showed that S100A12 was a pivotal gene related to inflammation and oxidative stress. Then, S100A12 overexpression was identified based on the included datasets. The pooled standard average deviation (SMD) also showed that S100A12 was upregulated in AMI (SMD = 1.36, 95% CI: 0.70-2.03, p = 0.024). The SROC curve analysis result suggested that S100A12 had remarkable diagnostic ability in AMI (AUC = 0.90, 95% CI: 0.87-0.92). And nine miRNAs targeting S100A12 were also identified. Additionally, the overexpression of S100A12 was further confirmed that it maybe promote inflammation and oxidative stress in AMI through comprehensive in vitro experiments. In summary, our study suggests that overexpressed S100A12 may be a latent diagnostic biomarker and therapeutic target of AMI that induces excessive inflammation and oxidative stress. Nine miRNAs targeting S100A12 may play a crucial role in AMI, but further studies are still needed. Our work provides a positive inspiration for the in-depth study of S100A12 in AMI.

Proteomics-based evaluation of the mechanism underlying vascular injury via DNA interstrand crosslinks, glutathione perturbation, mitogen-activated protein kinase, and Wnt and ErbB signaling pathways induced by crotonaldehyde

Crotonaldehyde (CRA)—one of the major environmental pollutants from tobacco smoke and industrial pollution—is associated with vascular injury (VI). We used proteomics to systematically characterize the presently unclear molecular mechanism of VI and to identify new related targets or signaling pathways after exposure to CRA. Cell survival assays were used to assess DNA damage, whereas oxidative stress was determined using colorimetric assays and by quantitative fluorescence study; additionally, cyclooxygenase-2, mitogen-activated protein kinase pathways, Wnt3a, β-catenin, phospho-ErbB2, and phospho-ErbB4 were assessed using ELISA. Proteins were quantitated via tandem mass tag-based liquid chromatography-mass spectrometry and bioinformatics analyses, and 34 differentially expressed proteins were confirmed using parallel reaction monitoring, which were defined as new indicators related to the mechanism underlying DNA damage; glutathione perturbation; mitogen-activated protein kinase; and the Wnt and ErbB signaling pathways in VI based on Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and protein–protein interaction network analyses. Parallel reaction monitoring confirmed significant (p < 0.05) upregulation (> 1.5-fold change) of 23 proteins and downregulation (< 0.667-fold change) of 11. The mechanisms of DNA interstrand crosslinks; glutathione perturbation; mitogen-activated protein kinase; cyclooxygenase-2; and the Wnt and ErbB signaling pathways may contribute to VI through their roles in DNA damage, oxidative stress, inflammation, vascular dysfunction, endothelial dysfunction, vascular remodeling, coagulation cascade, and the newly determined signaling pathways. Moreover, the Wnt and ErbB signaling pathways were identified as new disease pathways involved in VI. Taken together, the elucidated underlying mechanisms may help broaden existing understanding of the molecular mechanisms of VI induced by CRA.

Receptor for Advanced Glycation End Products (RAGE): A Pivotal Hub in Immune Diseases

As a critical molecule in the onset and sustainment of inflammatory response, the receptor for advanced glycation end products (RAGE) has a variety of ligands, such as advanced glycation end products (AGEs), S100/calcium granule protein, and high-mobility group protein 1 (HMGB1). Recently, an increasing number studies have shown that RAGE ligand binding can initiate the intracellular signal cascade, affect intracellular signal transduction, stimulate the release of cytokines, and play a vital role in the occurrence and development of immune-related diseases, such as systemic lupus erythematosus, rheumatoid arthritis, and Alzheimer’s disease. In addition, other RAGE signaling pathways can play crucial roles in life activities, such as inflammation, apoptosis, autophagy, and endoplasmic reticulum stress. Therefore, the strategy of targeted intervention in the RAGE signaling pathway may have significant therapeutic potential, attracting increasing attention. In this paper, through the systematic induction and analysis of RAGE-related signaling pathways and their regulatory mechanisms in immune-related diseases, we provide theoretical clues for the follow-up targeted intervention of RAGE-mediated diseases.

Pathophysiology of RAGE in inflammatory diseases

The receptor for advanced glycation end products (RAGE) is a non-specific multi-ligand pattern recognition receptor capable of binding to a range of structurally diverse ligands, expressed on a variety of cell types, and performing different functions. The ligand-RAGE axis can trigger a range of signaling events that are associated with diabetes and its complications, neurological disorders, cancer, inflammation and other diseases. Since RAGE is involved in the pathophysiological processes of many diseases, targeting RAGE may be an effective strategy to block RAGE signaling.

Multifunctional Role of S100 Protein Family in the Immune System: An Update

S100 is a broad subfamily of low-molecular weight calcium-binding proteins (9–14 kDa) with structural similarity and functional discrepancy. It is required for inflammation and cellular homeostasis, and can work extracellularly, intracellularly, or both. S100 members participate in a variety of activities in a healthy cell, including calcium storage and transport (calcium homeostasis). S100 isoforms that have previously been shown to play important roles in the immune system as alarmins (DAMPs), antimicrobial peptides, pro-inflammation stimulators, chemo-attractants, and metal scavengers during an innate immune response. Currently, during the pandemic, it was found that several members of the S100 family are implicated in the pathophysiology of COVID-19. Further, S100 family protein members were proposed to be used as a prognostic marker for COVID-19 infection identification using a nasal swab. In the present review, we compiled the vast majority of recent studies that focused on the multifunctionality of S100 proteins in the complex immune system and its associated activities. Furthermore, we shed light on the numerous molecular approaches and signaling cascades regulated by S100 proteins during immune response. In addition, we discussed the involvement of S100 protein members in abnormal defense systems during the pathogenesis of COVID-19.

Role of endothelial cells in vascular calcification

Vascular calcification (VC) is active and regulates extraosseous ossification progress, which is an independent predictor of cardiovascular disease (CVD) morbidity and mortality. Endothelial cells (ECs) line the innermost layer of blood vessels and directly respond to changes in flow shear stress and blood composition. Together with vascular smooth muscle cells, ECs maintain vascular homeostasis. Increased evidence shows that ECs have irreplaceable roles in VC due to their high plasticity. Endothelial progenitor cells, oxidative stress, inflammation, autocrine and paracrine functions, mechanotransduction, endothelial-to-mesenchymal transition (EndMT), and other factors prompt ECs to participate in VC. EndMT is a dedifferentiation process by which ECs lose their cell lineage and acquire other cell lineages; this progress coexists in both embryonic development and CVD. EndMT is regulated by several signaling molecules and transcription factors and ultimately mediates VC via osteogenic differentiation. The specific molecular mechanism of EndMT remains unclear. Can EndMT be reversed to treat VC? To address this and other questions, this study reviews the pathogenesis and research progress of VC, expounds the role of ECs in VC, and focuses on the regulatory factors underlying EndMT, with a view to providing new concepts for VC prevention and treatment.

Interferon-alpha2 treatment of patients with polycythemia vera and related neoplasms favorably impacts deregulation of oxidative stress genes and antioxidative defense mechanisms

Chronic inflammation is considered a major driving force for clonal expansion and evolution in the Philadelphia-negative myeloproliferative neoplasms, which include essential thrombocythemia, polycythemia vera and primary myelofibrosis (MPNs). One of the key mutation drivers is the JAK2V617F mutation, which has been shown to induce the generation of reactive oxygen species (ROS). Using whole blood gene expression profiling, deregulation of several oxidative stress and anti-oxidative defense genes has been identified in MPNs, including significant downregulation of TP53, the NFE2L2 or NRF2 genes. These genes have a major role for maintaining genomic stability, regulation of the oxidative stress response and in modulating migration or retention of hematopoietic stem cells. Therefore, their deregulation might give rise to increasing genomic instability, increased chronic inflammation and disease progression with egress of hematopoietic stem cells from the bone marrow to seed in the spleen, liver and elsewhere. Interferon-alpha2 (rIFNα) is increasingly being recognized as the drug of choice for the treatment of patients with MPNs. Herein, we report the first gene expression profiling study on the impact of rIFNα upon oxidative stress and antioxidative defense genes in patients with MPNs (n = 33), showing that rIFNα downregulates several upregulated oxidative stress genes and upregulates downregulated antioxidative defense genes. Treatment with rIFNα induced upregulation of 19 genes in ET and 29 genes in PV including CXCR4 and TP53. In conclusion, this rIFNα- mediated dampening of genotoxic damage to hematopoietic cells may ultimately diminish the risk of additional mutations and accordingly clonal evolution and disease progression towards myelofibrotic and leukemic transformation.

LPS and oxLDL-induced S100A12 and RAGE expression in carotid arteries of atherosclerotic Yucatan microswine

BACKGROUND

S100A12, also known as Calgranulin C, is a ligand for the receptor for advanced glycation end products (RAGE) and plays key roles in cardiovascular and other inflammatory diseases. Interactions between S100A12 and RAGE initiate downstream signaling activating extracellular signal-regulated kinases (ERK1/2), mitogen activated protein kinases (MAPK), and transcription factor NF-κB. This increases the expression of pro-inflammatory cytokines to induce the inflammatory response. S100A12, and RAGE play a critical role in the development and progression of atherosclerosis. There is a well-known relationship between the bacterial endotoxin lipopolysaccharide (LPS) and the lipid antigens oxidized low-density lipoprotein (oxLDL) in driving the immune response in atherosclerosis.

METHODS AND RESULTS

Our study aimed to compare the potential of LPS and oxLDL in regulating the expression of S100A12 and RAGE in atherosclerosis. The expression of these proteins was assessed in the harvested carotid arteries from LPS- and oxLDL-treated atherosclerotic Yucatan microswine. Tissues were collected from five different treatment groups: (i) angioplasty alone, (ii) LPS alone, (iii) oxLDL alone, (iv) angioplasty with LPS, and (v) angioplasty with oxLDL. Immunohistochemical findings revealed that angioplasty with LPS induced higher expression of S100A12 and RAGE compared to other treatment groups. The results were further corroborated by testing their gene expression through qPCR in cultured vascular smooth muscle cells (VSMCs) isolated from control carotid arteries and LPS- and oxLDL-treated arteries.

CONCLUSIONS

The results of this study suggest that LPS induces the expression of S100A12 and RAGE more than oxLDL in atherosclerotic artery and both S100A12 and RAGE could be therapeutic targets.

Integrated Analysis Reveals S100a8/a9 Regulates Autophagy and Apoptosis through the MAPK and PI3K-AKT Signaling Pathway in the Early Stage of Myocardial Infarction

Myocardial infarction (MI), a type of coronary heart disease, has had a significantly increased incidence in recent years. The balance of cardiomyocyte apoptosis and autophagy after MI is one of the main determinants of patient prognosis. Both affect myocardial fibrosis and ventricular remodeling and regulate cell survival. However, there are few studies on the regulation mechanism of cardiomyocyte autophagy and apoptosis in the early stage after MI. In this study, based on analyzing the scRNA-seq and mRNA-seq data of mice in the early stage of MI, we found that the expression of S100a8 and S100a9 increased first and then decreased in the early stage of MI, and their expression level changed with the number of neutrophils. Further, through the functional enrichment analysis of the differentially expressed genes, we found that S100a8 and S100a9 were simultaneously associated with autophagy and apoptosis and could regulate autophagy and apoptosis of cardiomyocytes through MAPK or PI3K-AKT signaling pathways. This study provides valuable insights for clarifying the pathogenesis of early stage MI and improving its early treatment.

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.

Inflammation: A New Look at an Old Problem

Pro-inflammatory stress is inherent in any cells that are subject to damage or threat of damage. It is defined by a number of universal components, including oxidative stress, cellular response to DNA damage, unfolded protein response to mitochondrial and endoplasmic reticulum stress, changes in autophagy, inflammasome formation, non-coding RNA response, formation of an inducible network of signaling pathways, and epigenetic changes. The presence of an inducible receptor and secretory phenotype in many cells is the cause of tissue pro-inflammatory stress. The key phenomenon determining the occurrence of a classical inflammatory focus is the microvascular inflammatory response (exudation, leukocyte migration to the alteration zone). This same reaction at the systemic level leads to the development of life-critical systemic inflammation. From this standpoint, we can characterize the common mechanisms of pathologies that differ in their clinical appearance. The division of inflammation into alternative variants has deep evolutionary roots. Evolutionary aspects of inflammation are also described in the review. The aim of the review is to provide theoretical arguments for the need for an up-to-date theory of the relationship between key human pathological processes based on the integrative role of the molecular mechanisms of cellular and tissue pro-inflammatory stress.

Involvement of Oxidative Stress in Protective Cardiac Functions of Calprotectin

Calprotectin (CLP) belonging to the S-100 protein family is a heterodimeric complex (S100A8/S100A9) formed by two binding proteins. Upon cell activation, CLP stored in neutrophils is released extracellularly in response to inflammatory stimuli and acts as damage-associated molecular patterns (DAMPs). S100A8 and S100A9 possess both anti-inflammatory and anti-bacterial properties. The complex is a ligand of the toll-like receptor 4 (TLR4) and receptor for advanced glycation end (RAGE). At sites of infection and inflammation, CLP is a target for oxidation due to its co-localization with neutrophil-derived oxidants. In the heart, oxidative stress (OS) responses and S100 proteins are closely related and intimately linked through pathophysiological processes. Our review summarizes the roles of S100A8, S100A9 and CLP in the inflammation in relationship with vascular OS, and we examine the importance of CLP for the mechanisms driving in the protection of myocardium. Recent evidence interpreting CLP as a critical modulator during the inflammatory response has identified this alarmin as an interesting drug target.

S100A9-CXCL12 activation in BRCA1-mutant breast cancer promotes an immunosuppressive microenvironment associated with resistance to immunotherapy

Immune checkpoint blockade (ICB) is a powerful approach for cancer therapy although good responses are only observed in a fraction of cancer patients. Breast cancers caused by deficiency of breast cancer-associated gene 1 (BRCA1) do not have an improved response to the treatment. To investigate this, here we analyze BRCA1 mutant mammary tissues and tumors derived from both BRCA1 mutant mouse models and human xenograft models to identify intrinsic determinants governing tumor progression and ICB responses. We show that BRCA1 deficiency activates S100A9-CXCL12 signaling for cancer progression and triggers the expansion and accumulation of myeloid-derived suppressor cells (MDSCs), creating a tumor-permissive microenvironment and rendering cancers insensitive to ICB. These oncogenic actions can be effectively suppressed by the combinatory treatment of inhibitors for S100A9-CXCL12 signaling with αPD-1 antibody. This study provides a selective strategy for effective immunotherapy in patients with elevated S100A9 and/or CXCL12 protein levels.

Transcriptomic Analysis Identifies Differentially Expressed Genes Associated with Vascular Cuffing and Chronic Inflammation Mediating Early Thrombosis in Arteriovenous Fistula

Arteriovenous fistula (AVF) is vascular access created for hemodialysis in end-stage renal disease patients. AVF creation causes increased blood flow in the outflow vein with increased pressure. Increased blood flow, blood volume, and shear stress causes outward remodeling so that the outflow vein can withstand the increased pressure. Outward remodeling of the vein involved in AVF is necessary for AVF maturation, however, inward remodeling due to excessive neointimal hyperplasia (NIH) and chronic inflammation may end up with vessel thrombosis and AVF maturation failure. Early thrombosis of the vessel may be due to the luminal factors including NIH and chronic inflammation or due to chronic inflammation of the adventitial due to perivascular cuffing. Inflammation may either be due to an immune response to the vascular injury during AVF creation or injury to the surrounding muscles and fascia. Several studies have discussed the role of inflammation in vascular thrombosis due to intimal injury during AVF creation, but there is limited information on the role of inflammation due to surrounding factors like a muscle injury. The concept of perivascular cuffing has been reported in the nervous system, but there is no study of perivascular cuffing in AVF early thrombosis. We performed the bulk RNA sequencing of the femoral arterial tissue and contralateral arteries as we found thrombosed arteries after AVF creation. RNA sequencing revealed several significantly differentially expressed genes (DEGs) related to chronic inflammation and perivascular cuffing, including tripartite motif-containing protein 55 (TRIM55). Additionally, DEGs like myoblast determination protein 1 (MYOD1) increased after muscle injury and relates to skeletal muscle differentiation, and network analysis revealed regulation of various genes regulating inflammation via MYOD1. The findings of this study revealed multiple genes with increased expression in the AVF femoral artery and may provide potential therapeutic targets or biomarkers of early thrombosis in AVF maturation failure. Thus, not only the luminal factors but also the surrounding factors mediating vascular cuffing contribute to vessel thrombosis and AVF failure via early thrombosis, and targeting the key regulatory factors may have therapeutic potential.

Role of the S100 protein family in rheumatoid arthritis

Rheumatoid arthritis is a chronic systemic autoimmune disease characterized by synovial hyperplasia, inflammatory cell infiltration, and proliferation of inflammatory tissue (angiogranuloma). The destruction of joints and surrounding tissues eventually causes joint deformities and dysfunction or even loss. The S100 protein family is one of the biggest subtribes in the calcium-binding protein family and has more than 20 members. The overexpression of most S100 proteins in rheumatoid arthritis is closely related to its pathogenesis. This paper reviews the relationship between S100 proteins and the occurrence and development of rheumatoid arthritis. It will provide insights into the development of new clinical diagnostic markers and therapeutic targets for rheumatoid arthritis.

Hyperglycemia Induces Inflammatory Response of Human Macrophages to CD163-Mediated Scavenging of Hemoglobin-Haptoglobin Complexes

Hyperglycemia, a hallmark of diabetes, can induce inflammatory programming of macrophages. The macrophage scavenger receptor CD163 internalizes and degrades hemoglobin-haptoglobin (Hb-Hp) complexes built due to intravascular hemolysis. Clinical studies have demonstrated a correlation between impaired scavenging of Hb-Hp complexes via CD163 and diabetic vascular complications. Our aim was to identify whether hyperglycemia is able to amplify inflammation via Hb-Hp complex interactions with the immune system. M(IFNγ), M(IL-4), and control M0 macrophages were differentiated out of primary human monocytes in normo- (5 mM) and hyperglycemic (25 mM) conditions. CD163 gene expression was decreased 5.53 times in M(IFNγ) with a further decrease of 1.99 times in hyperglycemia. Hyperglycemia suppressed CD163 surface expression in M(IFNγ) (1.43 times). Flow cytometry demonstrated no impairment of Hb-Hp uptake in hyperglycemia. However, hyperglycemia induced an inflammatory response of M(IFNγ) to Hb-Hp1-1 and Hb-Hp2-2 uptake with different dynamics. Hb-Hp1-1 uptake stimulated IL-6 release (3.03 times) after 6 h but suppressed secretion (5.78 times) after 24 h. Contrarily, Hb-Hp2-2 uptake did not affect IL-6 release after 6h but increased secretion after 24 h (3.06 times). Our data show that hyperglycemia induces an inflammatory response of innate immune cells to Hb-Hp1-1 and Hb-Hp2-2 uptake, converting the silent Hb-Hp complex clearance that prevents vascular damage into an inflammatory process, hereby increasing the susceptibility of diabetic patients to vascular complications.

Matrix Vesicles as a Therapeutic Target for Vascular Calcification

Vascular calcification (VC) is linked to an increased risk of heart disease, stroke, and atherosclerotic plaque rupture. It is a cell-active process regulated by vascular cells rather than pure passive calcium (Ca) deposition. In recent years, extracellular vesicles (EVs) have attracted extensive attention because of their essential role in the process of VC. Matrix vesicles (MVs), one type of EVs, are especially critical in extracellular matrix mineralization and the early stages of the development of VC. Vascular smooth muscle cells (VSMCs) have the potential to undergo phenotypic transformation and to serve as a nucleation site for hydroxyapatite crystals upon extracellular stimulation. However, it is not clear what underlying mechanism that MVs drive the VSMCs phenotype switching and to result in calcification. This article aims to review the detailed role of MVs in the progression of VC and compare the difference with other major drivers of calcification, including aging, uremia, mechanical stress, oxidative stress, and inflammation. We will also bring attention to the novel findings in the isolation and characterization of MVs, and the therapeutic application of MVs in VC.

Exercise as a Peripheral Circadian Clock Resynchronizer in Vascular and Skeletal Muscle Aging

Aging is characterized by several progressive physiological changes, including changes in the circadian rhythm. Circadian rhythms influence behavior, physiology, and metabolic processes in order to maintain homeostasis; they also influence the function of endothelial cells, smooth muscle cells, and immune cells in the vessel wall. A clock misalignment could favor vascular damage and indirectly also affect skeletal muscle function. In this review, we focus on the dysregulation of circadian rhythm due to aging and its relationship with skeletal muscle changes and vascular health as possible risk factors for the development of sarcopenia, as well as the role of physical exercise as a potential modulator of these processes.

Psycho-cardiology therapeutic effects of Shuangxinfang in rats with depression-behavior post acute myocardial infarction: Focus on protein S100A9 from proteomics

BACKGROUND

Depressive disorders induced by acute myocardial infarction (AMI) play a pivotal role in the deterioration of cardiac function, and Shuangxinfang (Psycho-cardiology Formula, PCF) was reported to alleviate heart function damage and improve depression-like behavior, but the complex mechanism in such process has not been clarified.

METHODS

AMI models were established and PCF was administered in rats. Subjects were then assessed in open field test (OFT) and forced swimming test (FST) recapitulating symptoms of depressive disorder. Afterward, pharmacoproteomic profiling of the hippocampus and peri-infarct border zone (BZ) was performed using a label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique, to identify contributing proteins and pathways responsible for myocardial ischemia and behavioral allostasis. Bioinformatics analysis was processed for further investigation, while western blotting was employed for testing dominating proteins to validate proteomic results.

RESULTS

Rats in the AMI group showed depression-like behavior in OFT and FST, which was improved by PCF. There were 131 differentially expressed proteins (DEPs) in BZ and 64 proteins in the hippocampus being detected and quantified shared by the sham group, the AMI group, and the PCF group. Subsequently, pertinent pathways and molecular functions were further identified. Altered molecules were discovered to be enriched in the apoptotic process, innate immune response, and NF-κB transcription factor activity in BZ, as well as chemical synaptic transmission, axon, collagen binding, cell adhesion, response to carbohydrate, laminin binding, and cellular response to nitric oxide in the hippocampus. Groups of signal transducers were also able to select multiple pathways, including innate immunity and arginine biosynthesis in the heart, also integrin signaling in the brain. DEPs were intersected from the myocardium and hippocampus to screen out the protein S100A9, which was up-regulated in the AMI group compared with the sham, and showed a down-regulation trend after treatment with PCF.

CONCLUSION

Taken together, we present a comprehensive proteomics analysis of rat models with depression post-AMI. Reviewing the literatures concerned, it's hypothesized that macrophage/microglia inflammation mediated by S100A9 might be the pivotal pathogenic process of psycho-cardiology disease, as well as potential mechanisms for the treatment of PCF.

Transcriptomic and Proteomic Profiling of Human Stable and Unstable Carotid Atherosclerotic Plaques

Atherosclerosis is a chronic inflammatory disease with high prevalence and mortality. The rupture of atherosclerotic plaque is the main reason for the clinical events caused by atherosclerosis. Making clear the transcriptomic and proteomic profiles between the stabe and unstable atherosclerotic plaques is crucial to prevent the clinical manifestations. In the present study, 5 stable and 5 unstable human carotid atherosclerotic plaques were obtained by carotid endarterectomy. The samples were used for the whole transcriptome sequencing (RNA-Seq) by the Next-Generation Sequencing using the Illumina HiSeq, and for proteome analysis by HPLC-MS/MS. The lncRNA-targeted genes and circRNA-originated genes were identified by analyzing their location and sequence. Gene Ontology and KEGG enrichment was carried out to analyze the functions of differentially expressed RNAs and proteins. The protein-protein interactions (PPI) network was constructed by the online tool STRING. The consistency of transcriptome and proteome were analyzed, and the lncRNA/circRNA-miRNA-mRNA interactions were predicted. As a result, 202 mRNAs, 488 lncRNAs, 91 circRNAs, and 293 proteins were identified to be differentially expressed between stable and unstable atherosclerotic plaques. The 488 lncRNAs might target 381 protein-coding genes by cis-acting mechanisms. Sequence analysis indicated the 91 differentially expressed circRNAs were originated from 97 protein-coding genes. These differentially expressed RNAs and proteins were mainly enriched in the terms of the cellular response to stress or stimulus, the regulation of gene transcription, the immune response, the nervous system functions, the hematologic activities, and the endocrine system. These results were consistent with the previous reported data in the dataset GSE41571. Further analysis identified CD5L, S100A12, CKB (target gene of lncRNA MSTRG.11455.17), CEMIP (target gene of lncRNA MSTRG.12845), and SH3GLB1 (originated gene of hsacirc_000411) to be critical genes in regulating the stability of atherosclerotic plaques. Our results provided a comprehensive transcriptomic and proteomic knowledge on the stability of atherosclerotic plaques.

Vascular inflammation in moderate-to-severe atopic dermatitis is associated with enhanced Th2 response

BACKGROUND

In atopic dermatitis (AD), some studies have shown an association with increased cardiovascular disease in certain populations. However, other investigations found modest or no association. Despite conflicting results, molecular profiling studies in both AD skin and blood have demonstrated upregulation of atherosclerosis and cardiovascular risk-related markers. However, the underlying mechanisms connecting AD to vascular inflammation/atherosclerosis are unknown. In this study, we aim to determine factors associated with vascular inflammation/atherosclerosis in AD patients.

METHODS

We used 18-FDG PET-CT to characterize vascular inflammation in AD patients and healthy subjects. In parallel, we assessed their skin and blood immune profiles to determine AD-related immune biomarkers associated with vascular inflammation. We also assessed levels of circulating microparticles, which are known to be associated with increased cardiovascular risk.

RESULTS

We found significant correlations between vascular inflammation and Th2-related products in skin and blood of AD patients as well as atherosclerosis-related markers that were modulated by dupilumab. Circulating levels of endothelial microparticles were significantly higher in severe AD patients and tended to correlate with vascular inflammation assessed by PET-CT.

CONCLUSION

Vascular inflammation in AD is associated with enhanced Th2 response and clinical severity, which may explain cardiovascular comorbidities observed in select AD populations. Larger prospective studies are needed to further evaluate vascular inflammation and cardiovascular events and mortality in AD patients. Finally, as dupilumab treatment demonstrated significant modulation of atherosclerosis-related genes in AD patients compared to placebo, these data suggest that modulation of vascular inflammation with systemic treatment should be explored in patients with AD.

Discerning the promising binding sites of S100/calgranulins and their therapeutic potential in atherosclerosis

INTRODUCTION

Atherosclerosis is a chronic inflammatory disease in which the members of S100 family proteins (calgranulins) bind with their receptors, particularly receptor for advanced glycation end products (RAGE) and toll-like receptor-4 (TLR-4) and play a key role in the pathogenesis and progression of disease. Thus, these proteins could be considered as potential biomarkers and therapeutic targets in the treatment of atherosclerotic inflammation.

AREAS COVERED

This review summarizes the pathology of S100A8, S100A9, and S100A12 in the development of atherosclerosis and reveals key structural features of these proteins which are potentially critical in their pathological effects. This article focuses on the translational significance of antagonizing these proteins by using small molecules in patent literature, clinical and preclinical studies and also discusses future approaches that could be employed to block these proteins in the treatment of atherosclerosis.

EXPERT OPINION

Based on the critical role of S100/calgranulins in the regulation of atherosclerosis, these proteins are potential targets to develop better therapeutic options in the treatment of inflammatory diseases. However, further research is still needed to clarify their exact molecular mechanism by analyzing their detailed structural features that can expedite future research to develop novel therapeutics against these proteins to treat atherosclerotic inflammation.

S100A8 and S100A9, both transcriptionally regulated by PU.1, promote epithelial-mesenchymal transformation (EMT) and invasive growth of dermal keratinocytes during scar formation post burn

S100 calcium-binding protein A8 (S100A8) and S100A9 are small molecular weight calcium-binding regulatory proteins that have been involved in multiple chronic inflammatory diseases. However, the role of S100A8 and S100A9 in keratinocytes in wounded skin and how they are regulated during this process are still unclear. Here, we found that S100A8 and S100A9 were both upregulated in burn-wounded skins in vivo and thermal-stimulated epidermal keratinocytes in vitro, accompanied by increased levels of epithelial-mesenchymal transition (EMT). Then, we demonstrated that upregulation of S100A8 and S100A9 alone or together enhanced characteristics of EMT in normal keratinocytes, manifested by excessive proliferation rate, abnormal ability of cell invasion, and high expression levels of EMT marker proteins. The transcription factor PU box-binding protein (PU.1) bound to the promoter regions and transcriptionally promoted the expression of S100A8 and S100A9 both in the human and mice, and it had strong positive correlations with both S100A8 and S100A9 protein levels in burned skin in vivo. Moreover, PU.1 positively regulated expression of S100A8 and S100A9 in a dose-dependent manner, and enhanced EMT of keratinocytes in vitro. Finally, through the burn mouse model, we found that PU.1-/- mice displayed a lower ability of scar formation, manifested by smaller scar volume, thickness, and collagen content, which could be enhanced by S100A8 and S100A9. In conclusion, PU.1 transcriptionally promotes expression of S100A8 and S100A9, thus positively regulating epithelial-mesenchymal transformation (EMT) and invasive growth of dermal keratinocytes during scar formation post burn.

Differences in Biomarkers of Inflammation Between Novel Subgroups of Recent-Onset Diabetes

A novel clustering approach identified five subgroups of diabetes with distinct progression trajectories of complications. We hypothesized that these subgroups differ in multiple biomarkers of inflammation. Serum levels of 74 biomarkers of inflammation were measured in 414 individuals with recent adult-onset diabetes from the German Diabetes Study (GDS) allocated to five subgroups based on data-driven cluster analysis. Pairwise differences between subgroups for biomarkers were assessed with generalized linear mixed models before (model 1) and after (model 2) adjustment for the clustering variables. Participants were assigned to five subgroups: severe autoimmune diabetes (21%), severe insulin-deficient diabetes (SIDD) (3%), severe insulin-resistant diabetes (SIRD) (9%), mild obesity-related diabetes (32%), and mild age-related diabetes (35%). In model 1, 23 biomarkers showed one or more pairwise differences between subgroups (Bonferroni-corrected P < 0.0007). Biomarker levels were generally highest in SIRD and lowest in SIDD. All 23 biomarkers correlated with one or more of the clustering variables. In model 2, three biomarkers (CASP-8, EN-RAGE, IL-6) showed at least one pairwise difference between subgroups (e.g., lower CASP8, EN-RAGE, and IL-6 in SIDD vs. all other subgroups, all P < 0.0007). Thus, novel diabetes subgroups show multiple differences in biomarkers of inflammation, underlining a prominent role of inflammatory pathways in particular in SIRD.

Pro-inflammatory Mediators and Oxidative Stress: Therapeutic Markers for Recurrent Angina Pectoris after Coronary Artery Stenting in Elderly Patients

BACKGROUND

Pro-inflammatory mediators and oxidative stress are related to severity of angina pectoris in patients with coronary heart disease.

OBJECTIVE

We evaluated the effects of pro-inflammatory mediators and oxidative stress on recurrent angina pectoris after coronary artery stenting in elderly patients.

METHODS

We determined the expression levels of malondialdehyde (MDA), acrolein (ACR), tumour necrosis factor-α (TNF-α), toll-like receptor 4 (TLR4), superoxide dismutase 3 (SOD3), paraoxonase-1 (PON-1), stromal cell-derived factor-1α (SDF-1α) and endothelial progenitor cells (EPCs) in elderly patients with recurrent angina pectoris after coronary artery stenting.

RESULTS

Levels of MDA, ACR, TNF-α and TLR4 were significantly increased (p<0.001), and levels of SOD3, PON-1, SDF-1α and EPCs were significantly decreased (p<0.001) in the elderly patients with recurrent angina pectoris after coronary artery stenting. MDA, ACR, TNF-α and TLR4 as markers of oxidative stress and pro-inflammatory mediators may have suppressed SOD3, PON-1, SDF-1α and EPCs as markers of anti-oxidative stress/anti-inflammatory responses. Oxidative stress and pro-inflammatory mediators were important factors involved in recurrent angina pectoris of elderly patients after coronary artery stenting.

CONCLUSION

Oxidative stress and pro-inflammatory mediators could be considered as potential non-invasive prognostic, predictive and therapeutic biomarkers for stable recurrent angina and recurrent unstable angina in the elderly patients after coronary artery stenting.

Inhibition of miR‑101‑3p protects against sepsis‑induced myocardial injury by inhibiting MAPK and NF‑κB pathway activation via the upregulation of DUSP1

Numerous studies have found that microRNAs (miRNAs or miRs) are aberrantly expressed when sepsis occurs. The present study aimed to investigate the role of miR-101-3p in sepsis-induced myocardial injury and to elucidate the underlying mechanisms. Models of myocardial injury were established both in vivo and in vitro. The results revealed that miR-101-3p was upregulated in the serum of patients with sepsis-induced cardiomyopathy (SIC) and positively correlated with the levels of pro-inflammatory cytokines (including IL-1β, IL-6 and TNF-α). Subsequently, rats were treated with miR-101-3p inhibitor to suppress miR-101-3p and were then exposed to lipopolysaccharide (LPS). The results revealed that LPS induced marked cardiac dysfunction, apoptosis and inflammation. The inhibition of miR-101-3p markedly attenuated sepsis-induced myocardial injury by attenuating apoptosis and the expression of pro-inflammatory cytokines. Mechanistically, dual specificity phosphatase-1 (DUSP1) was found to be a functional target of miR-101-3p. The downregulation of miR-101-3p led to the overexpression of DUSP1, and the inactivation of the MAPK p38 and NF-κB pathways. Moreover, blocking DUSP1 by short hairpin RNA against DUSP1 (sh-DUSP1) significantly reduced the myocardial protective effects mediated by the inhibition of miR-101-3p. Collectively, the findings of the present study demonstrate that the inhibition of miR-101-3p exerts cardioprotective effects by suppressing MAPK p38 and NF-κB pathway activation, and thus attenuating inflammation and apoptosis dependently by enhancing DUSP1 expression.

Immunological mechanisms underlying sterile inflammation in the pathogenesis of atherosclerosis: potential sites for intervention

Introduction: Innate and adaptive immunity play a critical role in the underlying pathological mechanisms of atherosclerosis and potential target sites of sterile inflammation open opportunities to develop novel therapeutics. In response to oxidized LDL in the intimal layer, T cell subsets are recruited and activated at the site of atheroma to upregulate pro-atherogenic cytokines which exacerbate plaque formation instability.Areas covered: A systematic search of PubMed and the Web of Science was performed between January 2001- September 2020 and relevant articles in sterile inflammation and atherosclerosis were critically reviewed. The original information was collected on the interconnection between danger associated molecular patterns (DAMPs) as the mediators of sterile inflammation and the receptor complex of CD36-TLR4-TLR6 that primes and activates inflammasomes in the pathophysiology of atherosclerosis. Mediators of sterile inflammation are identified to target therapeutic strategies in the management of atherosclerosis.Expert opinion: Sterile inflammation via NLRP3 inflammasome is perpetuated by the activation of IL-1β and IL-18 and induction of pyroptosis resulting in the release of additional inflammatory cytokines and DAMPs. Challenges with current inhibitors of the NLRP3 inflammasome lie in the specificity, stability, and efficacy in targeting the NLRP3 inflammasome constituents without ameliorating upstream or downstream responses necessary for survival.

Serum proteins may facilitate the identification of Kawasaki disease and promote in vitro neutrophil infiltration

Kawasaki disease (KD) usually affects the children younger than 5 years of age and subsequently causes coronary artery lesions (CALs) without timely identification and treatment. Developing a robust and fast prediction method may facilitate the timely diagnosis of KD, significantly reducing the risk of CALs in KD patients. The levels of inflammatory serum proteins dramatically vary during the onsets of many immune diseases, including in KD. However, our understanding of their pathogenic roles in KD is behind satisfaction. The purpose of this study was to evaluate candidate diagnostic serum proteins and the potential mechanism in KD using iTRAQ gel-free proteomics. We enrolled subjects and conducted iTRAQ gel-free proteomics to globally screen serum proteins followed by specific validation with ELISA. Further in vitro leukocyte trans-endothelial model was also applied to investigate the pathogenesis roles of inflammatory serum proteins. We identified six KD protein biomarkers, including Protein S100-A8 (S100A8), Protein S100-A9 (S100A9), Protein S100-A12 (S100A12), Peroxiredoxin-2 (PRDX2), Neutrophil defensin 1 (DEFA1) and Alpha-1-acid glycoprotein 1 (ORM1). They enabled us to develop a high-performance KD prediction model with an auROC value of 0.94, facilitating the timely identification of KD. Further assays concluded that recombinant S100A12 protein treatment activated neutrophil surface adhesion molecules responsible for adhesion to endothelial cells. Therefore, S100A12 promoted both freshly clinically isolated neutrophils and neutrophil-like cells to infiltrate through the endothelial layer in vitro. Finally, the antibody against S100A12 may attenuate the infiltration promoted by S100A12. Our result demonstrated that evaluating S100A8, S100A9, S100A12, PRDX2, DEFA1 and ORM1 levels may be a good diagnostic tool of KD. Further in vitro study implied that S100A12 could be a potential therapeutic target for KD.

Therapeutic Potential of Polyphenols-Loaded Polymeric Nanoparticles in Cardiovascular System

Numerous studies document an increased production of reactive oxygen species (ROS) with a subsequent decrease in nitric oxide (NO) bioavailability in different cardiovascular diseases, including hypertension, atherosclerosis, and heart failure. Many natural polyphenols have been demonstrated to decrease ROS generation and/or to induce the endogenous antioxidant enzymatic defense system. Moreover, different polyphenolic compounds have the ability to increase the activity/expression of endothelial nitric oxide synthase (eNOS) with a subsequent enhancement of NO generation. However, as a result of low absorption and bioavailability of natural polyphenols, the beneficial effects of these substances are very limited. Recent progress in delivering polyphenols to the targeted tissues revealed new possibilities for the use of polymeric nanoparticles in increasing the efficiency and reducing the degradability of natural polyphenols. This review focuses on the effects of different natural polyphenolic substances, especially resveratrol, quercetin, curcumin, and cherry extracts, and their ability to bind to polymeric nanoparticles, and summarizes the effects of polyphenol-loaded nanoparticles, mainly in the cardiovascular system.

Proteomic biomarkers in Gaucher disease

AIMS

The research work was conducted to find new biomarkers and potential drug targets in Gaucher disease type 1 (GDt1) by analysing the serum proteins.

METHODS

This study was an observational, cross-sectional analysis of a group of 12 adult participants: six Gaucher disease (GD) patients and six healthy control. Fasting venous blood underwent proteomics analysis and molecular tests. Over 400 proteins were analysed, and in case of significantly different concentrations between the study and control group, we checked corresponding genes to confirm changes in their expression and consistency with protein alteration.

RESULTS

We found 31 proteins that significantly differed in concentration between GDt1 patients and a control group. These were mostly proteins involved in the regulation of the inflammatory processes and haemostasis. The levels of proteins such as alpha-1-acid glycoprotein 2, S100-A8/A9, adenyl cyclase-associated protein 1, haptoglobin or translationally controlled tumour protein related to inflammation process were significantly higher in GD patients than in control group, whereas the levels of some proteins such as heavy constant mu and gamma 4 or complement C3/C4 complex involved in humoral response like immunoglobulins were significantly decreased in GD patients. Alteration in two proteins concentration was confirmed in RNA analysis.

CONCLUSIONS

The work revealed few new targets for further investigation which may be useful in clinical practice for diagnosis, treatment and monitoring GDt1 patients.

Roles of S100 family members in drug resistance in tumors: Status and prospects

Chemotherapy and targeted therapy can significantly improve survival rates in cancer, but multiple drug resistance (MDR) limits the efficacy of these approaches. Understanding the molecular mechanisms underlying MDR is crucial for improving drug efficacy and clinical outcomes of patients with cancer. S100 proteins belong to a family of calcium-binding proteins and have various functions in tumor development. Increasing evidence demonstrates that the dysregulation of various S100 proteins contributes to the development of drug resistance in tumors, providing a basis for the development of predictive and prognostic biomarkers in cancer. Therefore, a combination of biological inhibitors or sensitizers of dysregulated S100 proteins could enhance therapeutic responses. In this review, we provide a detailed overview of the mechanisms by which S100 family members influence resistance of tumors to cancer treatment, with a focus on the development of effective strategies for overcoming MDR.