Cholesterol crystals use complement to increase NLRP3 signaling pathways in coronary and carotid atherosclerosis

Oxidative Stress-Mediated Programmed Cell Death: a Potential Therapy Target for Atherosclerosis

Nowadays, as a type of orderly and active death determined by genes, programmed cell death (PCD), including apoptosis, pyroptosis, ferroptosis, and necroptosis, has attracted much attention owing to its participation in numerous chronic cardiovascular diseases, especially atherosclerosis (AS), a canonical chronic inflammatory disease featured by lipid metabolism disturbance. Abundant researches have reported that PCD under distinct internal conditions fulfills different roles of atherosclerotic pathological processes, including lipid core expansion, leukocyte adhesion, and infiltration. Noteworthy, emerging evidence recently has also suggested that oxidative stress (OS), an imbalance of antioxidants and oxygen free radicals, has the potential to mediate PCD occurrence via multiple ways, including oxidization and deubiquitination. Interestingly, more recently, several studies have proposed that the mediating mechanisms could effect on the atherosclerotic initiation and progression significantly from variable aspects, so it is of great clinical importance to clarify how OS-mediated PCD and AS interact. Herein, with the aim of summarizing potential and sufficient atherosclerotic therapy targets, we seek to provide extensive analysis of the specific regulatory mechanisms of PCD mediated by OS and their multifaceted effects on the entire pathological atherosclerotic progression.

Paeonol attenuated high glucose-induced apoptosis via up-regulating miR-223-3p in mouse cardiac microvascular endothelial cells

To investigate the role of miR-223-3p in the modulatory effect of paeonol (Pae) on high glucose (HG)-induced endothelial cell apoptosis. HG (25 mmol/L) was used to induce cellular damage and apoptosis in the mouse cardiac microvascular endothelial cells (MCMECs). Various concentration of Pae was tested and 60 μmol/L Pae was selected for the subsequent studies. MCMECs were transfected with exogenous miR-223-3p mimics or anti-miR-223-3p inhibitors. Cell viability was assessed by MTT assay and apoptosis was quantified by flow cytometry. The expression of miR-223-3p and NLRP3 mRNA was measured using real-time quantitative RT-PCR, and protein level of NLRP3 and apoptosis-related proteins was detected by immunoblotting. Pae significantly attenuated HG-induced apoptosis of MCMECs in a concentration-dependent manner. In addition, Pae (60 µmol/L) significantly reversed HG-induced down-regulation of miR-223-3p and up-regulation of NLRP3. Pae (60 µmol/L) also significantly blocked HG-induced up-regulation of Bax and Caspase-3 as well as down-regulation of Bcl-2. Moreover, exogenous miR-223-3p mimics not only significantly attenuated HG-induced apoptosis, but also significantly suppressed NRLP-3 and pro-apoptotic proteins in the MCMECs. In contrast, transfection of exogenous miR-223-3p inhibitors into the MCMECs resulted in not only significantly increased apoptosis of the cells, but also significant suppression of NLRP3 and pro-apoptotic proteins in the cells. Pae attenuated HG-induced apoptosis of MCMECs in a concentration-dependent manner. MiR-223-3p may mediate the modulatory effects of Pae on MCMEC survival or apoptosis through targeting NLRP3 and regulating apoptosis-associated proteins.

Chronic HIV Infection Increases Monocyte NLRP3 Inflammasome-Dependent IL-1α and IL-1β Release

Antiretroviral treatment (ART) has converted HIV from a lethal disease to a chronic condition, yet co-morbidities persist. Incomplete immune recovery and chronic immune activation, especially in the gut mucosa, contribute to these complications. Inflammasomes, multi-protein complexes activated by innate immune receptors, appear to play a role in these inflammatory responses. In particular, preliminary data indicate the involvement of IFI16 and NLRP3 inflammasomes in chronic HIV infection. This study explores inflammasome function in monocytes from people with HIV (PWH); 22 ART-treated with suppressed viremia and 17 untreated PWH were compared to 33 HIV-negative donors. Monocytes were primed with LPS and inflammasomes activated with ATP in vitro. IFI16 and NLRP3 mRNA expression were examined in a subset of donors. IFI16 and NLRP3 expression in unstimulated monocytes correlated negatively with CD4 T cell counts in untreated PWH. For IFI16, there was also a positive correlation with viral load. Monocytes from untreated PWH exhibit increased release of IL-1α, IL-1β, and TNF compared to treated PWH and HIV-negative donors. However, circulating monocytes in PWH are not pre-primed for inflammasome activation in vivo. The findings suggest a link between IFI16, NLRP3, and HIV progression, emphasizing their potential role in comorbidities such as cardiovascular disease. The study provides insights into inflammasome regulation in HIV pathogenesis and its implications for therapeutic interventions.

Navigating the Maze of Kinases: CaMK-like Family Protein Kinases and Their Role in Atherosclerosis

Circulating low-density lipoprotein (LDL) levels are a major risk factor for cardiovascular diseases (CVD), and even though current treatment strategies focusing on lowering lipid levels are effective, CVD remains the primary cause of death worldwide. Atherosclerosis is the major cause of CVD and is a chronic inflammatory condition in which various cell types and protein kinases play a crucial role. However, the underlying mechanisms of atherosclerosis are not entirely understood yet. Notably, protein kinases are highly druggable targets and represent, therefore, a novel way to target atherosclerosis. In this review, the potential role of the calcium/calmodulin-dependent protein kinase-like (CaMKL) family and its role in atherosclerosis will be discussed. This family consists of 12 subfamilies, among which are the well-described and conserved liver kinase B1 (LKB1) and 5' adenosine monophosphate-activated protein kinase (AMPK) subfamilies. Interestingly, LKB1 plays a key role and is considered a master kinase within the CaMKL family. It has been shown that LKB1 signaling leads to atheroprotective effects, while, for example, members of the microtubule affinity-regulating kinase (MARK) subfamily have been described to aggravate atherosclerosis development. These observations highlight the importance of studying kinases and their signaling pathways in atherosclerosis, bringing us a step closer to unraveling the underlying mechanisms of atherosclerosis.

The clinical role of combined circulating complement C1q and AIP for CAD with LDL-C level below 1.8mmol/L

BACKGROUND

In the past few years, circulating complement C1q involvement in atherosclerosis has garnered growing research interest in addition to the emerging recognition of the novel lipid marker named atherogenic index of plasma (AIP). Nevertheless, among patients experiencing low-density lipoprotein cholesterol (LDL-C) levels less than 1.8mmol/L, the interplay between C1q combined with the AIP for coronary artery disease (CAD) is ambiguous.

METHODS

Patients were stratified into a non-CAD and CAD group according to their coronary angiography. The association between C1q in conjunction with the AIP and CAD was explored using restricted cubic spline analyses and logistic regression models. To assess how it predicted, a receiver operating characteristic analysis was undertaken.

RESULTS

A total of 7270 patients comprised 1476 non-CAD patients and 5794 patients diagnosed with CAD were analyzed. A comparison of the two groups showed that the C1q levels were notably higher compared to the CAD group, while AIP exhibited an inverse trend. Across quartiles of C1q, the AIP demonstrated a decline with increasing C1q levels, and significant differences were observed between the groups. A correlation analysis underscored a notable negative correlation between the two variables. Univariate and multivariate logistic regression analyses revealed significant associations between CAD and the C1q quartile groups/AIP. Furthermore, compared with the Q4 group, a decrease in the C1q levels corresponded to an escalation in CAD risk, with the odds ratio rising from 1.661 to 2.314.

CONCLUSIONS

In conclusion, there appears to be a notable positive correlation between the combination of C1q with the AIP and CAD.

Vinpocetine represses the progression of nonalcoholic steatohepatitis in mice by mediating inflammasome components via NF-κB signaling

BACKGROUND

Inflammasome activation is known to be involved in nonalcoholic steatohepatitis (NASH). Vinpocetine is a derivative of vincamine and is reported to suppress the activation of inflammasome.

METHODS

This study explored the therapeutical potential of Vinpocetine on NASH. Mice were fed with a choline-deficient (MCD) or chow diet in the presence or absence of Vinpocetine for 8 weeks. H&E staining and biochemical assays were determined to evaluate the hepatic steatosis and fibrosis symptoms. In addition, primary hepatocytes and Kupffer cells were isolated and induced by MCD or lipopolysaccharides/cholesterol crystals with or without Vinpocetine. ELISAs, qPCR, and Western blotting were applied to determine the levels of NASH-related biomarkers in both in vivo mouse model and in vitro cell models.

RESULTS

Treatment of Vinpocetine did not cause observable side effects against and MCD-induced cells and mouse NASH model. However, treatment of Vinpocetine ameliorated hepatic steatosis and fibrosis and suppressed the levels of alanine transaminase and aspartate transferase in the mouse NASH model. In addition, treatment of Vinpocetine suppressed the mRNA and protein levels of inflammasome components both in vitro and in vivo.

CONCLUSION

Vinpocetine suppressed NASH in mice by mediating inflammasome components via nuclear factor κB signaling.

Vascular smooth muscle cells in response to cholesterol crystals modulates inflammatory cytokines release and promotes neutrophil extracellular trap formation

BACKGROUND

The formation and accumulation of cholesterol crystals (CC) at the lesion site is a hallmark of atherosclerosis. Although studies have shown the importance of vascular smooth muscle cells (VSMCs) in the disease atherosclerosis, little is known about the molecular mechanism behind the uptake of CC in VSMCs and their role in modulating immune response.

METHODS

Human aortic smooth muscle cells were cultured and treated with CC. CC uptake and CC mediated signaling pathway and protein induction were studied using flow cytometry, confocal microscopy, western blot and Olink proteomics. Conditioned medium from CC treated VSMCs was used to study neutrophil adhesion, ROS production and phagocytosis. Neutrophil extracellular traps (NETs) formations were visualized using confocal microscopy.

RESULTS

VSMCs and macrophages were found around CC clefts in human carotid plaques. CC uptake in VSMCs are largely through micropinocytosis and phagocytosis via PI3K-AkT dependent pathway. The uptake of CC in VSMCs induce the release inflammatory proteins, including IL-33, an alarming cytokine. Conditioned medium from CC treated VSMCs can induce neutrophil adhesion, neutrophil reactive oxygen species (ROS) and neutrophil extracellular traps (NETs) formation. IL-33 neutralization in conditioned medium from CC treated VSMCs inhibited neutrophil ROS production and NETs formation.

CONCLUSION

We demonstrate that VSMCs due to its vicinity to CC clefts in human atherosclerotic lesion can modulate local immune response and we further reveal that the interaction between CC and VSMCs impart an inflammatory milieu in the atherosclerotic microenvironment by promoting IL-33 dependent neutrophil influx and NETs formation.

Cholesterol crystals at the culprit lesion in patients with acute coronary syndrome are associated with worse cardiovascular outcomes at two years follow up - results from the translational OPTICO-ACS study program

BACKGROUND

Cholesterol crystals (CCs) represent a feature of advanced atherosclerotic plaque and may be assessed by optical coherence tomography (OCT). Their impact on cardiovascular outcomes in patients presenting with acute coronary syndromes (ACS) is yet unknown.

METHODS

The culprit lesion (CL) of 346 ACS-patients undergoing preintervention OCT imaging were screened for the presence of CCs and divided into two groups accordingly. The primary end-point was the rate of major adverse cardiac events plus (MACE+) consisting of cardiac death, myocardial infarction, target vessel revascularization and re-hospitalization due to unstable or progressive angina at two years.

RESULTS

Among 346 patients, 57.2% presented with CCs at the CL. Patients with CCs exhibited a higher prevalence of ruptured fibrous caps (RFC-ACS) (79.8% vs. 56.8%; p < 0.001) and other high-risk features such as thin cap fibroatheroma (80.8% vs. 64.9%; p = 0.001), presence of macrophages (99.0% vs. 85.1%; p < 0.001) as well as a greater maximum lipid arc (294.0° vs. 259.3°; p < 0.001) at the CL as compared to patients without CCs. MACE+ at two years follow-up occurred more often in CC-patients (29.2% vs. 16.1%; p = 0.006) as compared to patients without CCs at the culprit site. Multivariable cox regression analysis identified CCs as independent predictor of MACE+ (HR 1.705; 1.025-2.838 CI, p = 0.040).

CONCLUSIONS

CCs were associated with conventional high-risk plaque features and associated with increased MACE+-rates at two years follow up. The identification of CCs might be useful as prognostic marker in patients with ACS and assist "precision prevention" in the future.

Food-derived peptides as novel therapeutic strategies for NLRP3 inflammasome-related diseases: a systematic review

NLRP3 (NOD-, LRR- and pyrin domain-containing protein 3), a member of the nucleotide-binding domain (NOD) and leucine-rich repeat sequence (LRR) protein (NLR) family, plays an essential role in the inflammation initiation and inflammatory mediator secretion, and thus is also associated with many disease progressions. Food-derived bioactive peptides (FDBP) exhibit excellent anti-inflammatory activity in both in vivo and in vitro models. They are encrypted in plant, meat, and milk proteins and can be released under enzymatic hydrolysis or fermentation conditions, thereby hindering the progression of hyperuricemia, inflammatory bowel disease, chronic liver disease, neurological disorders, lung injury and periodontitis by inactivating the NLRP3. However, there is a lack of systematic review around FDBP, NLRP3, and NLRP3-related diseases. Therefore, this review summarized FDBP that exert inhibiting effects on NLRP3 inflammasome from different protein sources and detailed their preparation and purification methods. Additionally, this paper also compiled the possible inhibitory mechanisms of FDBP on NLRP3 inflammasomes and its regulatory role in NLRP3 inflammasome-related diseases. Finally, the progress of cutting-edge technologies, including nanoparticle, computer-aided screening strategy and recombinant DNA technology, in the acquisition or encapsulation of NLRP3 inhibitory FDBP was discussed. This review provides a scientific basis for understanding the anti-inflammatory mechanism of FDBP through the regulation of the NLRP3 inflammasome and also provides guidance for the development of therapeutic adjuvants or functional foods enriched with these FDBP.

Restraint stress promotes nonalcoholic steatohepatitis by regulating the farnesoid X receptor/NLRP3 signaling pathway

Psychological stress promotes nonalcoholic steatohepatitis (NASH) development. However, the pathogenesis of psychological stress-induced NASH remains unclear. This study aims to explore the underlying mechanism of restraint stress-induced NASH, which mimics psychological stress, and to discover potential NASH candidates. Methionine choline deficient diet- and high fat diet-induced hepatosteatotic mice are subjected to restraint stress to induce NASH. The mice are administrated with Xiaoyaosan granules, NOD-like receptor family pyrin domain containing 3 (NLRP3) inhibitors, farnesoid X receptor (FXR) agonists, or macrophage scavengers. Pathological changes and NLRP3 signaling in the liver are determined. These results demonstrate that restraint stress promotes hepatic inflammation and fibrosis in hepatosteatotic mice. Restraint stress increases the expressions of NLRP3, Caspase-1, Gasdermin D, interleukin-1β, cholesterol 7α-hydroxylase, and sterol 12α-hydroxylase and decreases the expression of FXR in NASH mice. Xiaoyaosan granules reverse hepatic inflammation and fibrosis and target FXR and NLRP3 signals. In addition, inhibition of NLRP3 reduces the NLRP3 inflammasome and liver damage in mice with restraint stress-induced NASH. Elimination of macrophages and activation of FXR also attenuate inflammation and fibrosis by inhibiting NLRP3 signaling. However, NLRP3 inhibitors or macrophage scavengers fail to affect the expression of FXR. In conclusion, restraint stress promotes NASH-related inflammation and fibrosis by regulating the FXR/NLRP3 signaling pathway. Xiaoyaosan granules, NLRP3 inhibitors, FXR agonists, and macrophage scavengers are potential candidates for the treatment of psychological stress-related NASH.

Complement C1q and von Willebrand factor interaction in atherosclerosis of human carotid artery

Atherosclerosis is an inflammatory disease of the vessel wall, with cholesterol crystal (CC) deposition being a hallmark of the disease. As evidence for a cross-talk between complement activation and hemostasis on CC surfaces has been limited to in vitro data, the aim of this study was to demonstrate the presence of C1q-vWF complexes in human atherosclerosis ex vivo. We used immunofluorescence staining and a proximity ligation assay (PLA, Duolink®) to examine the presence, localization, and co-localization of C1q and vWF in frozen sections of human carotid arteries with atherosclerosis or without atherosclerotic changes as well as material from thrombendarteriectomy. We observed significantly higher levels of C1q and vWF in healthy tissue compared to diseased material and greater co-localization in the PLA in healthy samples than in diseased samples. In diseased samples, fluorescence signals were highest in locations encompassing atheroma and foam cells. While there was overall reduced signal in areas with CCs, the staining was spotty, and there was evidence of co-localization on individual CCs. Thus, we demonstrate the presence of C1q-vWF complexes in human carotid arteries ex vivo, which was most abundant in healthy endothelial and subendothelial space and reduced in diseased tissue. C1q-vWF interaction can also be demonstrated on the CC surface.

C5a-C5aR1 induces endoplasmic reticulum stress to accelerate vascular calcification via PERK-eIF2α-ATF4-CREB3L1 pathway

AIMS

Vascular calcification (VC) predicts the morbidity and mortality in cardiovascular diseases. Vascular smooth muscle cells (VSMCs) osteogenic transdifferentiation is the crucial pathological basis for VC. To date, the molecular pathogenesis is still largely unclear. Notably, C5a-C5aR1 contributes to the development of cardiovascular diseases, and its closely related to physiological bone mineralization which is similar to VSMCs osteogenic transdifferentiation. However, the role and underlying mechanisms of C5a-C5aR1 in VC remain unexplored.

METHODS AND RESULTS

A cross-sectional clinical study was utilized to examine the association between C5a and VC. Chronic kidney diseases mice and calcifying VSMCs models were established to investigate the effect of C5a-C5aR1 in VC, evaluated by changes in calcium deposition and osteogenic markers. The cross-sectional study identified that high level of C5a was associated with increased risk of VC. C5a dose-responsively accelerated VSMCs osteogenic transdifferentiation accompanying with increased the expression of C5aR1. Meanwhile, the antagonists of C5aR1, PMX 53, reduced calcium deposition, and osteogenic transdifferentiation both in vivo and in vitro. Mechanistically, C5a-C5aR1 induced endoplasmic reticulum (ER) stress and then activated PERK-eIF2α-ATF4 pathway to accelerated VSMCs osteogenic transdifferentiation. In addition, cAMP-response element-binding protein 3-like 1 (CREB3L1) was a key downstream mediator of PERK-eIF2α-ATF4 pathway which accelerated VSMCs osteogenic transdifferentiation by promoting the expression of COL1α1.

CONCLUSIONS

High level of C5a was associated with increased risk of VC, and it accelerated VC by activating the receptor C5aR1. PERK-eIF2α-ATF4-CREB3L1 pathway of ER stress was activated by C5a-C5aR1, hence promoting VSMCs osteogenic transdifferentiation. Targeting C5 or C5aR1 may be an appealing therapeutic target for VC.

Efficacy and safety of inhibiting the NLRP3/IL-1β/IL-6 pathway in patients with ST-elevation myocardial infarction: A meta-analysis

BACKGROUND

The NLRP3/IL-1β/IL-6 pathway plays a key role in mediating inflammatory responses after ST-elevation myocardial infarction (STEMI). However, the clinical benefits of inhibiting this pathway in STEMI are uncertain. We aimed to evaluate the efficacy and safety of inhibiting the NLRP3/IL-1β/IL-6 pathway in STEMI patients.

METHODS

This study followed PRISMA guidelines. PubMed, Embase, CENTRAL and ClinicalTrials.gov databases were searched for randomized controlled trials (RCTs) of inhibiting the NLRP3/IL-1β/IL-6 pathway in STEMI patients within 7 days of symptom onset. The efficacy outcomes included all-cause death, cardiovascular death, recurrent MI, new-onset or worsening heart failure (HF) and stroke. The safety outcomes were serious infection, gastrointestinal adverse events and injection site reactions.

RESULTS

Of 316 screened records, nine trials with 1211 patients were included in the meta-analysis. Colchicine reduced the risk of recurrent MI (RR 0.28, 95% CI 0.10-0.74; I2  = 0.0%). Anakinra was associated with reduced risk of new-onset or worsening HF (RR 0.32, 95% CI 0.13-0.77; I2  = 0.0%) and decreased C-reactive protein levels (SMD -1.34, 95% CI -2.04 to -0.65; I2  = 0.0%). Colchicine and anakinra increased the risk of gastrointestinal adverse events (RR 4.43, 95% CI 2.75-7.13; I2  = 38.1%) and injection site reactions (RR 4.52, 95% CI 1.32-15.49; I2  = 0.8%), respectively. None of the three medications affected the risks of all-cause death, cardiovascular death, stroke and serious infection.

CONCLUSIONS

There is still no large-scale RCT evidence on the efficacy and safety of inhibiting the NLRP3/IL-1β/IL-6 pathway for the treatment of STEMI. Preliminary results from the available RCTs suggest colchicine and anakinra may respectively reduce the risks of recurrent MI and new-onset or worsening HF. The available RCTs in this meta-analysis lack power to determine any differences on mortality.

Role of neutrophil extracellular trap and immune infiltration in atherosclerotic plaque instability: Novel insight from bioinformatics analysis and machine learning

The instability of atherosclerotic plaques increases the risk of acute coronary syndrome. Neutrophil extracellular traps (NETs), mesh-like complexes consisting of extracellular DNA adorned with various protein substances, have been recently discovered to play an essential role in atherosclerotic plaque formation and development. This study aimed to investigate novel diagnostic biomarkers that can identify unstable plaques for early distinction and prevention of plaque erosion or disruption. Differential expression analysis was used to identify the differentially expressed NET-related genes, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed. We filtered the characteristic genes using machine learning and estimated diagnostic efficacy using receiver operating characteristic curves. Immune infiltration was detected using single-sample gene set enrichment analysis and the biological signaling pathways involved in characteristic genes utilizing gene set enrichment analysis were explored. Finally, miRNAs- and transcription factors-target genes networks were established. We identified 8 differentially expressed NET-related genes primarily involved in immune-related pathways. Four were identified as capable of distinguishing unstable plaques. More immune cells infiltrated unstable plaques than stable plaques, and these cells were predominantly positively related to characteristic genes. These 4 diagnostic genes are involved in immune responses and the modulation of smooth muscle contractility. Several miRNAs and transcription factors were predicted as upstream regulatory factors, providing further information on the identification and prevention of atherosclerotic plaques rupture. We identified several promising NET-related genes (AQP9, C5AR1, FPR3, and SIGLEC9) and immune cell subsets that may identify unstable atherosclerotic plaques at an early stage and prevent various complications of plaque disruption.

Oligosaccharides as Potential Therapeutics against Atherosclerosis

Atherosclerosis is the major cause of cardiovascular-disease-related death worldwide, resulting from the subendothelial accumulation of lipoprotein-derived cholesterol, ultimately leading to chronic inflammation and the formation of clinically significant atherosclerotic plaques. Oligosaccharides have been widely used in biomedical research and therapy, including tissue engineering, wound healing, and drug delivery. Moreover, oligosaccharides have been consumed by humans for centuries, and are cheap, and available in large amounts. Given the constantly increasing number of obesity, diabetes, and hyperlipidaemia cases, there is an urgent need for novel therapeutics that can economically and effectively slow the progression of atherosclerosis. In this review, we address the current state of knowledge in oligosaccharides research, and provide an update of the recent in vitro and in vivo experiments that precede clinical studies. The application of oligosaccharides could help to eliminate the residual risk after the application of other cholesterol-lowering medicines, and provide new therapeutic opportunities to reduce the associated burden of premature deaths because of atherosclerosis.

Portrayal of NLRP3 Inflammasome in Atherosclerosis: Current Knowledge and Therapeutic Targets

We are witnessing the globalization of a specific type of arteriosclerosis with rising prevalence, incidence and an overall cardiovascular disease burden. Currently, atherosclerosis increasingly affects the younger generation as compared to previous decades. While early preventive medicine has seen improvements, research advances in laboratory and clinical investigation promise to provide us with novel diagnosis tools. Given the physio-pathological complexity and epigenetic patterns of atherosclerosis and the discovery of new molecules involved, the therapeutic field of atherosclerosis has room for substantial growth. Thus, the scientific community is currently investigating the role of nucleotide-binding and oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, a crucial component of the innate immune system in different inflammatory disorders. NLRP3 is activated by distinct factors and numerous cellular and molecular events which trigger NLRP3 inflammasome assembly with subsequent cleavage of pro-interleukin (IL)-1β and pro-IL-18 pathways via caspase-1 activation, eliciting endothelial dysfunction, promotion of oxidative stress and the inflammation process of atherosclerosis. In this review, we introduce the basic cellular and molecular mechanisms of NLRP3 inflammasome activation and its role in atherosclerosis. We also emphasize its promising therapeutic pharmaceutical potential.

Complosome - the intracellular complement system

The complement system is a recognized pillar of host defence against infection and noxious self-derived antigens. Complement is traditionally known as a serum-effective system, whereby the liver expresses and secretes most complement components, which participate in the detection of bloodborne pathogens and drive an inflammatory reaction to safely remove the microbial or antigenic threat. However, perturbations in normal complement function can cause severe disease and, for reasons that are currently not fully understood, the kidney is particularly vulnerable to dysregulated complement activity. Novel insights into complement biology have identified cell-autonomous and intracellularly active complement - the complosome - as an unexpected central orchestrator of normal cell physiology. For example, the complosome controls mitochondrial activity, glycolysis, oxidative phosphorylation, cell survival and gene regulation in innate and adaptive immune cells, and in non-immune cells, such as fibroblasts and endothelial and epithelial cells. These unanticipated complosome contributions to basic cell physiological pathways make it a novel and central player in the control of cell homeostasis and effector responses. This discovery, together with the realization that an increasing number of human diseases involve complement perturbations, has renewed interest in the complement system and its therapeutic targeting. Here, we summarize the current knowledge about the complosome across healthy cells and tissues, highlight contributions from dysregulated complosome activities to human disease and discuss potential therapeutic implications.

Metaflammation in glucolipid metabolic disorders: Pathogenesis and treatment

The public health issue of glucolipid metabolic disorders (GLMD) has grown significantly, posing a grave threat to human wellness. Its prevalence is rising yearly and tends to affect younger people. Metaflammation is an important mechanism regulating body metabolism. Through a complicated multi-organ crosstalk network involving numerous signaling pathways such as NLRP3/caspase-1/IL-1, NF-B, p38 MAPK, IL-6/STAT3, and PI3K/AKT, it influences systemic metabolic regulation. Numerous inflammatory mediators are essential for preserving metabolic balance, but more research is needed to determine how they contribute to the co-morbidities of numerous metabolic diseases. Whether controlling the inflammatory response can influence the progression of GLMD determines the therapeutic strategy for such diseases. This review thoroughly examines the role of metaflammation in GLMD and combs the research progress of related therapeutic approaches, including inflammatory factor-targeting drugs, traditional Chinese medicine (TCM), and exercise therapy. Multiple metabolic diseases, including diabetes, non-alcoholic fatty liver disease (NAFLD), cardiovascular disease, and others, respond therapeutically to anti-inflammatory therapy on the whole. Moreover, we emphasize the value and open question of anti-inflammatory-based means for treating GLMD.

Porphyromonas gingivalis regulates atherosclerosis through an immune pathway

Atherosclerosis (AS) is a chronic inflammatory disease, involving a pathological process of endothelial dysfunction, lipid deposition, plaque rupture, and arterial occlusion, and is one of the leading causes of death in the world population. The progression of AS is closely associated with several inflammatory diseases, among which periodontitis has been shown to increase the risk of AS. Porphyromonas gingivalis (P. gingivalis), presenting in large numbers in subgingival plaque biofilms, is the “dominant flora” in periodontitis, and its multiple virulence factors are important in stimulating host immunity. Therefore, it is significant to elucidate the potential mechanism and association between P. gingivalis and AS to prevent and treat AS. By summarizing the existing studies, we found that P. gingivalis promotes the progression of AS through multiple immune pathways. P. gingivalis can escape host immune clearance and, in various forms, circulate with blood and lymph and colonize arterial vessel walls, directly inducing local inflammation in blood vessels. It also induces the production of systemic inflammatory mediators and autoimmune antibodies, disrupts the serum lipid profile, and thus promotes the progression of AS. In this paper, we summarize the recent evidence (including clinical studies and animal studies) on the correlation between P. gingivalis and AS, and describe the specific immune mechanisms by which P. gingivalis promotes AS progression from three aspects (immune escape, blood circulation, and lymphatic circulation), providing new insights into the prevention and treatment of AS by suppressing periodontal pathogenic bacteria.

Bibliometric evaluation of publications on inflammasomes in atherosclerosis from 2002 to 2022

Background

Inflammasomes have emerged as an important and promising area of investigation in atherosclerosis. This field, however, lacks bibliometric studies. To help understand how basic and clinical research on inflammasomes in atherosclerosis will develop in the future, we used bibliometric analysis to visualize hotspots and trends.

Methods

Studies related to inflammasomes in atherosclerosis were collected from the Web of Science Core Collection database. Each study was analyzed bibliometrically and visually. CiteSpace and VOSviewer software were used to generate knowledge maps.

Results

A total of 894 articles were identified. Sixty-two countries and 338 institutions led by China and the United States contributed to these publications. The leading research institutions were Harvard Medical School and Columbia University. Circulation was the most frequently cited journal in this field. Among the 475 authors determined, Eicke Latz authored the most studies, and Peter Duewell has been cocited the most. NLRP3 inflammasome, NF-kappa B, macrophage and oxidative stress are the most commonly used keywords.

Conclusion

There has been a blooming of research on inflammasomes in atherosclerosis during the last two decades. Future studies will likely explore the molecular mechanism of inflammasomes in cell death. More compellingly, researchers may further delve into the potential clinical value of affecting pathological changes in atherosclerosis by modulating the initial transcription immune response and intracellular multiprotein assembly process of the NLRP3 inflammasome. Our research will be helpful to scholars focusing on inflammation-a much-needed breakthrough in the pathophysiological alterations of atherosclerosis-with a novel perspective.

The relationships between cholesterol crystals, NLRP3 inflammasome, and coronary atherosclerotic plaque vulnerability in acute coronary syndrome: An optical coherence tomography study

BACKGROUND

Cholesterol crystals (CCs) in lesions are the hallmark of advanced atherosclerotic plaque. Previous studies have demonstrated that CCs could activate NLRP3 inflammasome, which played an important role in atherosclerotic lesion progression. However, the relationship between CCs, NLRP3 inflammasome pathway, and plaque vulnerability in patients with ACS is still not elucidated.

METHODS

Two hundred sixty-nine consecutive acute coronary syndrome (ACS) patients with 269 culprit lesions were included in this study. CCs and other plaque characteristics within the culprit lesion segment were evaluated by optical coherence tomography (OCT) before percutaneous coronary intervention (PCI). The NLRP3 mRNA expression in peripheral blood mononuclear cells (PBMCs) and the serum levels of interleukin (IL)-1β, IL-18, and other biological indices were measured.

RESULTS

Cholesterol crystals were observed in 105 (39%) patients with 105 culprit lesions. There were no significant differences in baseline clinical characteristics between the patients with CCs (CCs group, n = 105) and the patients without CCs (non-CCs group, n = 164) within the culprit lesion segment except for lipoprotein(a) [Lp(a)]. The CCs group had a higher level of NLRP3 mRNA expression in PBMCs and higher levels of serum cytokine IL-1β and IL-18. OCT showed that the CCs group had longer lesion length, more severe diameter stenosis, and less minimum luminal area (MLA) than the non-CCs group (all p < 0.05). The frequency of thin-cap fibroatheroma (TCFA), thrombus, accumulation of macrophages, plaque rupture, micro-channel, calcification, spotty calcification, and layered plaque was higher in the CCs group than in the non-CCs groups (all p < 0.05). Multivariate logistic analysis revealed that the level of NLRP3 expression (OR = 10.204), IL-1β levels (OR = 3.523), IL-18 levels (OR = 1.006), TCFA (OR = 3.593), layered plaque (OR = 5.287), MLA (OR = 1.475), macrophage accumulation (OR = 2.881), and micro-channel (OR = 3.185) were independently associated with CCs.

CONCLUSION

Acute coronary syndrome patients with CCs in culprit lesions had a higher expression of NLRP3, IL-1β, and IL-18, and had more vulnerable plaque characteristics than patients without CCs. CCs might have interacted with NLRP3 inflammasome activation in patients with ACS, which could contribute to plaque vulnerability in culprit lesions.

Identifying Hub Genes and Immune Cell Infiltration for the Progression of Carotid Atherosclerotic Plaques in the Context of Predictive and Preventive Using Integrative Bioinformatics Approaches and Machine-Learning Strategies

Emerging evidence shows that carotid atherosclerosis is related to the activation of immune-related pathways and inflammatory cell infiltration. However, the immune-linked pathways that helped in the advancement of the carotid atherosclerotic plaque and the association of such plaques with the infiltration status of the body's immune cells still unclear. Here, the expression profiles of the genes expressed during the progression of the carotid atherosclerotic plaques were retrieved from the Gene Expression Omnibus database and 178 differentially expressed genes were examined. The Weighted Gene Coexpression Network Analysis technique identified one of the brown modules showed the greatest correlation with carotid atherosclerotic plaques. In total, 66 intersecting genes could be detected after combining the DEGs. LASSO regression analysis was subsequently performed to obtain five hub genes as potential biomarkers for carotid atherosclerotic plaques. The functional analysis emphasized the vital roles played by the inflammation- and immune system-related pathways in this disease. The immune cell infiltration results highlighted the significant correlation among the CD4+ T cells, B cells, macrophages, and CD8+ T cells. Thereafter, the gene expression levels and the diagnostic values related to every hub gene were further validated. The above results indicated that macrophages, B cells, CD4+ T cells, and CD8 + T cells were closely related to the formation of the advanced-stage carotid atherosclerotic plaques. Based on the results, it could be hypothesized that the expression of hub genes (C3AR1, SLAMF8, TMEM176A, FERMT3, and GIMAP4) assisted in the advancement of the early-stage to advanced-stage carotid atherosclerotic plaque through immune-related signaling pathways. This may help to provide novel strategies for the treatment of carotid plaque in the context of predictive, preventive, and personalized medicine.

Identification of potential drug targets for vascular dementia and carotid plaques by analyzing underlying molecular signatures shared by them

Background

Vascular dementia (VaD) and carotid atherosclerotic plaques are common in the elderly population, conferring a heavy burden on families and society. Accumulating evidence indicates carotid atherosclerotic plaques to be a risk factor for VaD. However, the underlying mechanisms for this association are mainly unknown.

Materials and methods

We analyzed temporal cortex gene expression data of the GSE122063 dataset and gene expression data of the GSE163154 dataset to identify commonly differentially expressed genes (DEGs). Then we performed functional enrichment analysis, immune cell infiltration and evaluation, correlation analysis between differentially expressed immune-related genes (DEIRGs) and immune cells, receiver operating characteristic (ROC) analysis, and drug-gene analysis.

Results

We identified 41 overlapped DEGs between the VaD and carotid atherosclerosis plaque datasets. Functional enrichment analyses revealed that these overlapped DEGs were mainly enriched in inflammatory and immune-related processes. Immunocyte infiltration and evaluation results showed that M0 macrophages, M2 macrophages, and T cells gamma delta had a dominant abundance in carotid atherosclerosis plaque samples, and M0 macrophages showed a significantly different infiltration percentage between the early and advanced stage plaques group. Resting CD4 memory T cells, M2 macrophages, and naive B cells were the top three highest infiltrating fractions in VaD. Furthermore, B cells and NK cells showed a different infiltration percentage between VaD and matched controls. We identified 12 DEIRGs, and the result of correlation analysis revealed that these DEIRGs were closely related to differentially expressed immune cells. We identified five key DEIRGs based on ROC analysis. The drug-gene interaction analysis showed that four drugs (avacopan, CCX354, BMS-817399, and ASK-8007) could be potential drugs for VaD and carotid atherosclerotic plaques treatment.

Conclusion

Collectively, these findings indicated that inflammatory and immune-related processes be a crucial common pathophysiological mechanism shared by VaD and carotid plaques. This study might provide new insights into common molecular mechanisms between VaD and carotid plaques and potential targets for the treatment.

NLRP3 Inflammasome as a Therapeutic Target for Atherosclerosis: A Focus on Potassium Outflow

Atherosclerosis is a risk factor for various cardiovascular diseases, and is linked to high rates of morbidity and mortality across the globe. Although numerous complex processes are involved in the development and progression of atherosclerosis, the exact mechanisms behind its pathogenesis remain unclear. Inflammation and endothelial cell damage exert a lasting effect on atherosclerosis, causing lipid and fibrous tissue accumulation in the intima of the artery to form plaques, and subsequently promoting atherosclerosis. Nod-like receptor protein 3 (NLRP3) inflammatory corpuscle is thought to be the link between lipid metabolism and inflammation. Long Potassium outflow is a vital activator of NLRP3, with a simultaneous effect as a start-up and adjustment. The majority of existing drugs for atherosclerosis targeting the NLRP3 signaling pathway target IL-1, whereas drugs targeting the critical link of potassium efflux are relatively new. This review discusses the NLRP3 inflammatory corpuscle as a critical regulator of the immunological inflammatory pathway in atherosclerosis. Moreover, current knowledge on NLRP3 inflammatory corpuscle start and activation pathways were integrated, emphasizing potassium-involved outflow-related proteins. We highlight potential treatment approaches for NLRP3 inflammatory corpuscle pathways, specifically targeting potassium outflow channels of targeted drugs. Collectively, these insights indicate that targeting the NLRP3 inflammatory corpuscle is a vital anti-inflammatory therapy for treating atherosclerosis.

The crosstalk between NLRP3 inflammasome and gut microbiome in atherosclerosis

Atherosclerosis (AS) is chronic pathological process based on the inflammatory reaction associated with factors including vascular endothelial dysfunction, inflammation, and autoimmunity. Inflammasomes are known to be at the core of the inflammatory response. As a pattern recognition receptor of innate immunity, the NLRP3 inflammasome mediates the secretion of inflammatory factors by activating the Caspase-1, which is important for maintaining the immune system and regulating the gut microbiome, and participates in the occurrence and development of AS. The intestinal microecology is composed of a large number of complex structures of gut microbiota and its metabolites, which play an important role in AS. The gut microbiota and its metabolites regulate the activation of the NLRP3 inflammasome. Targeting the NLRP3 inflammasome and regulating intestinal microecology represent a new direction for the treatment of AS. This paper systematically reviews the interaction between the NLRP3 inflammasome and gut microbiome in AS, strategies for targeting the NLRP3 inflammasome and gut microbiome for the treatment of AS, and provides new ideas for the research and development of drugs for the treatment of AS.

Molecular basis of acute coronary syndrome

Cardiovascular diseases (CVD) comprise of various heart and blood vessels-related diseases. Acute coronary syndrome (ACS) is one of them. Basic researchers and cardiologists have witnessed landmark developments related to ACS and despite rapid refinement in our understanding; scientists are seeking answers for more questions. Scientists have mapped wide ranging proteins and intricate protein networks which play central role in the pathogenesis in ACS. In this review, we have attempted to summarize underlying causes of ACS. Better understanding of the disease pathology will enable us to get a step closer to an effective clinical management.

Could anakinra outmatch dexamethasone/tocilizumab in COVID-19?

The hyperinflammatory state leading to an aberrant cytokine production, culminating in acute respiratory distress syndrome, sepsis and multi-organ dysfunction contribute much to the pathophysiologies of severe COVID-19. These severe patients have similar clinical manifestations with patients suffering from certain auto-inflammatory disorders and cytokine storm syndromes. Interestingly, anakinra (blocking both IL-1α and IL-1β) has shown promises in treating these patients with hyperinflammatory disorders, sepsis with multiorgan failures. Another inflammasome, AIM2, involved in production of IL-1 has also been found to be implicated in COVID-19. IL-1β, a known procoagulant, causes induction of tissue factor with increasing vascular endothelial permeability loss ensuing in hypercoagulability-one of the cardinal features of the disease. Hence, anakinra a 17kD recombinant human IL-1 receptor antagonist, used widely in Rheumatoid Arthritis treatments might prove efficacious in attenuating the hyperinflammatory state of the disease. Indeed, some of the controlled clinical trials have shown anakinra to effectively decrease mortality and hospital stay. Targeted cytokine blocking are always preferable in comparison with non-specific blocking (steroids) as it is more restrained with the chances of dampening of systemic immune system being much less. Early cell death and neutrophil migration have been one of the pivotal events in COVID-19 pathogenesis. Hence, suPAR levels which measures IL-1α (necroptosis) and S100A8/A9 (neutrophil migration) can perhaps be a good early biomarker predicting the disease progression. Lastly and importantly, as the vaccines are raised against spike protein and the different variants of concern are known to evade the neutralizing antibodies by varying degrees, it will be deserving to assess anakinra, against the variants of concern as an immunomodulatory drug.

Secreted frizzled-related protein 4 exerts anti-atherosclerotic effects by reducing inflammation and oxidative stress

Atherosclerosis and its sequelae, such as coronary artery disease (CAD), are the most common diseases worldwide and the leading causes of morbidity and mortality in most countries. Our previous studies have shown that circulating secreted frizzled-related protein 4 (SFRP4) levels are increased in patients with CAD. However, the role of SFRP4 in the development of atherosclerosis remains unclear; thus, the purpose of this study was to determine the effect of SFRP4 on high-fat diet (HFD)-induced atherosclerosis and explore the possible mechanisms. In this study, we found for the first time that administration of recombinant SFRP4 alleviates atherosclerosis in ApoE-/- mice by reducing inflammation and oxidative stress. In addition, the anti-atherosclerotic effect of SFRP4 was associated with inhibition of the Wnt/β-catenin signaling pathway, and Wnt1 overexpression abolished the anti-atherosclerotic effects of SFRP4. Taken together, our results highlight the potential beneficial effect of SFRP4 as a therapeutic agent for atherosclerosis and CAD.

Targeting the Inflammasome in Cardiovascular Disease

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Development of cardiovascular disease and inflammation are heavily intertwined, and inflammasome activation is thought play an important role in this interaction.

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This review provides an overview of preclinical and clinical studies supporting inflammasomes as a therapeutic target in atherosclerosis and heart failure.

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Future studies exploring direct inflammasome inhibition, either NLRP3 or the lesser-studied inflammasomes, are also discussed.

The pathogenesis of cardiovascular disease (CVD) is complex and multifactorial, and inflammation plays a central role. Inflammasomes are multimeric protein complexes that are activated in a 2-step manner in response to infection or tissue damage. Upon activation the proinflammatory cytokines, interleukins-1β and -18 are released. In the last decade, the evidence that inflammasome activation plays an important role in CVD development became stronger. We discuss the role of different inflammasomes in the pathogenesis of CVD, focusing on atherosclerosis and heart failure. This review also provides an overview of existing experimental studies and clinical trials on inflammasome inhibition as a therapeutic target in these disorders.

Mitochondrial C5aR1 activity in macrophages controls IL-1β production underlying sterile inflammation

While serum-circulating complement destroys invading pathogens, intracellularly active complement, termed the “complosome,” functions as a vital orchestrator of cell-metabolic events underlying T cell effector responses. Whether intracellular complement is also nonredundant for the activity of myeloid immune cells is currently unknown. Here, we show that monocytes and macrophages constitutively express complement component (C) 5 and generate autocrine C5a via formation of an intracellular C5 convertase. Cholesterol crystal sensing by macrophages induced C5aR1 signaling on mitochondrial membranes, which shifted ATP production via reverse electron chain flux toward reactive oxygen species generation and anaerobic glycolysis to favor IL-1β production, both at the transcriptional level and processing of pro–IL-1β. Consequently, atherosclerosis-prone mice lacking macrophage-specific C5ar1 had ameliorated cardiovascular disease on a high-cholesterol diet. Conversely, inflammatory gene signatures and IL-1β produced by cells in unstable atherosclerotic plaques of patients were normalized by a specific cell-permeable C5aR1 antagonist. Deficiency of the macrophage cell-autonomous C5 system also protected mice from crystal nephropathy mediated by folic acid. These data demonstrate the unexpected intracellular formation of a C5 convertase and identify C5aR1 as a direct modulator of mitochondrial function and inflammatory output from myeloid cells. Together, these findings suggest that the complosome is a contributor to the biologic processes underlying sterile inflammation and indicate that targeting this system could be beneficial in macrophage-dependent diseases, such as atherosclerosis.

Phospholipid nanoparticles: Therapeutic potentials against atherosclerosis via reducing cholesterol crystals and inhibiting inflammation

Background

Atherosclerosis-related cardiovascular diseases (CVDs) are the leading cause of mortality worldwide. Cholesterol crystals (CCs) induce inflammation in atherosclerosis and are associated with unstable plaques and poor prognosis, but no drug can remove CCs in the clinic currently.

Methods

We generated a phospholipid-based and high-density lipoprotein (HDL)-like nanoparticle, miNano, and determined CC-dissolving capacity, cholesterol efflux property, and anti-inflammation effects of miNano in vitro. Both normal C57BL/6J and Apoe-deficient mice were used to explore the accumulation of miNano in atherosclerotic plaques. The efficacy and safety of miNano administration to treat atherosclerosis were evaluated in the Ldlr-deficient atherosclerosis model. The CC-dissolving capacity of miNano was also detected using human atherosclerotic plaques ex vivo.

Findings

We found that miNano bound to and dissolved CCs efficiently in vitro, and miNano accumulated in atherosclerotic plaques, co-localized with CCs and macrophages in vivo. Administration of miNano inhibited atherosclerosis and improved plaque stability by reducing CCs and macrophages in Ldlr-deficient mice with favorable safety profiles. In macrophages, miNano prevented foam cell formation by enhancing cholesterol efflux and suppressed inflammatory responses via inhibiting TLR4-NF-κB pathway. Finally, in an ex vivo experiment, miNano effectively dissolved CCs in human aortic atherosclerotic plaques.

Interpretation

Together, our work finds that phospholipid-based and HDL-like nanoparticle, miNano, has the potential to treat atherosclerosis by targeting CCs and stabilizing plaques.

Funding

This work was supported by the National Institutes of Health HL134569, HL109916, HL136231, and HL137214 to Y.E.C, HL138139 to J.Z., R21NS111191 to A.S., by the American Heart Association 15SDG24470155, Grant Awards (U068144 from Bio-interfaces and G024404 from M-BRISC) at the University of Michigan to Y.G., by the American Heart Association 19PRE34400017 and Rackham Helen Wu award to M.Y., NIH T32 GM07767 to K. H., Barbour Fellowship to D.L.

Cardamonin inhibits osteogenic differentiation of human valve interstitial cells and ameliorates aortic valve calcification via interfering in the NF-κB/NLRP3 inflammasome pathway

Cardamonin (CDM) is a natural chalcone with strong anti-inflammatory properties. Inflammation-induced osteogenic changes in valve interstitial cells (VICs) play crucial roles in the development of calcific aortic valve disease (CAVD), a degenerative disease characterized by degeneration, thickening, fibrosis, and calcification of the heart valve tissues. To investigate the anti-osteogenic differentiation role of CDM in human valve interstitial cells (hVICs), which consequently reverses the calcification of the aortic valve, human VICs were exposed to osteogenic induction medium (OM) with CDM for further cell viability, osteogenic gene and protein expression analyses, and anti-calcification testing. mRNA sequencing was utilized to analyze the differentially expressed genes (DEGs) and related signaling pathways as potential molecular targets involved in CDM's anti-calcification activity. Human aortic valve leaflet ex vivo calcific cultures were used to investigate the CDM inhibition of osteogenic differentiation of hVICs at the tissue level. ApoE^-/- mice fed with a high-fat (HF) diet were used to evaluate the effect of CDM on aortic valve calcification. No significant CDM cytotoxicity was seen in the hVICs at 10 μM. The addition of CDM to OM prevented calcified nodule accumulation, and a decrease in the gene/protein expression levels of BMP2, RUNX2, SPP1, TNF-α, and COL1A2 was observed. Venn diagram analysis of the DEGs identified 666 common DEGs and highlighted the NOD-like receptor signaling pathway (ko04621) as an anti-calcification target of CDM. CDM also repressed the activation of p-AKT, p-ERK1/2, and p-IκBα, and prevented the OM-induced nuclear transcription of NF-κB p65. In the in vitro and ex vivo calcific conditional culture experiments, CDM exhibited anti-inflammatory and anti-calcification effects by suppressing the activation of the NLRP3 inflammasome and downregulating IL-1β expression. In vivo, CDM ameliorated aortic valve calcification by interfering with NLRP3 expression. Our study demonstrated that CDM inhibited the phenotypical calcific transformation of hVICs by mediating the inactivation of the NF-κB/NLRP3 inflammasome. Therefore, it is considered to be a promising natural compound for use in preventing the progression of heart valve calcification disease.

The Role of the Inflammasome in Heart Failure

Inflammation promotes the development of heart failure (HF). The inflammasome is a multimeric protein complex that plays an essential role in the innate immune response by triggering the cleavage and activation of the proinflammatory cytokines interleukins (IL)-1β and IL-18. Blocking IL-1β with the monoclonal antibody canakinumab reduced hospitalizations and mortality in HF patients, suggesting that the inflammasome is involved in HF pathogenesis. The inflammasome is activated under various pathologic conditions that contribute to the progression of HF, including pressure overload, acute or chronic overactivation of the sympathetic system, myocardial infarction, and diabetic cardiomyopathy. Inflammasome activation is responsible for cardiac hypertrophy, fibrosis, and pyroptosis. Besides inflammatory cells, the inflammasome in other cardiac cells initiates local inflammation through intercellular communication. Some inflammasome inhibitors are currently being investigated in clinical trials in patients with HF. The current evidence suggests that the inflammasome is a critical mediator of cardiac inflammation during HF and a promising therapeutic target. The present review summarizes the recent advances in both basic and clinical research on the role of the inflammasome in HF.

Formation and Cellular Impact of Cholesterol Crystals in Health and Disease

Cholesterol crystals (CCs) were first discovered in atherosclerotic plaque tissue in the early 1900 and have since been observed and implicated in many diseases and conditions, including myocardial infarction, abdominal aortic aneurism, kidney disease, ocular diseases, and even central nervous system anomalies. Despite the widespread involvement of CCs in many pathologies, the mechanisms involved in their formation and their role in various diseases are still not fully understood. Current knowledge concerning the formation of CCs, as well as the molecular pathways activated upon cellular exposure to CCs, will be explored in this review. As CC formation is tightly associated with lipid metabolism, the role of cellular lipid homeostasis in the formation of CCs is highlighted, including the role of lysosomes. In addition, cellular pathways and processes known to be affected by CCs are described. In particular, CC-induced activation of the inflammasome and production of reactive oxygen species, along with the role of CCs in complement-mediated inflammation is discussed. Moreover, the clinical manifestation of embolized CCs is described with a focus on renal and skin diseases associated with CC embolism. Lastly, potential therapeutic measures that target either the formation of CCs or their impact on different cell types and tissues are highlighted.

The Role of ABC Transporters in Lipid Metabolism and the Comorbid Course of Chronic Obstructive Pulmonary Disease and Atherosclerosis

Chronic obstructive pulmonary disease (COPD) ranks among the leading causes of morbidity and mortality worldwide. COPD rarely occurs in isolation and is often combined with various diseases. It is considered that systemic inflammation underlies the comorbid course of COPD. The data obtained in recent years have shown the importance of violations of the cross-links of lipid metabolism and the immune response, which are links in the pathogenesis of both COPD and atherosclerosis. The role of lipid metabolism disorders in the pathogenesis of the comorbid course of COPD and atherosclerosis and the participation of ATP-binding cassette (ABC) transporters in these processes is discussed in this article. It is known that about 20 representatives of a large family of ABC transporters provide lipid homeostasis of cells by moving lipids inside the cell and in its plasma membrane, as well as removing lipids from the cell. It was shown that some representatives of the ABC-transporter family are involved in various links of the pathogenesis of COPD and atherosclerosis, which can determine their comorbid course.

Pyroptosis: A New Regulating Mechanism in Cardiovascular Disease

Pyroptosis is a kind of pro-inflammatory cell death. Compared with autophagy and apoptosis, pyroptosis has unique characteristics in morphology and mechanism. Specifically, pyroptosis is a kind of cell lysis mediated by the Gasdermin family, releases inflammatory cytokines IL-1β and IL-18. There are three different forms of mechanism, which are caspase-1-mediated, caspase-4/5/11-mediated and caspase-3-mediated. A large number of studies have proved that pyroptosis is closely related to cardiovascular disease. This paper reviewed the recent progress in the related research on pyroptosis and myocardial infarction, ischemia-reperfusion, atherosclerosis, diabetic cardiomyopathy, arrhythmia, heart failure hypertension and Kawasaki disease. Therefore, we believe that pyroptosis may be a new therapeutic target in the cardiovascular field.

Regulation of crystal induced inflammation: current understandings and clinical implications

Introduction: Accumulation of abnormal crystals in the body, derived from endogenous or exogenous materials can drive a wide spectrum of inflammatory disease states. It is well established that intra-articular deposition of monosodium urate (MSU) and calcium pyrophoshate (CPP) crystals contributes to joint destruction through pro-inflammatory processes.Areas covered: This review will focus on current understanding and recent novelty about the mechanisms and the clinical implications of the inflammation induced by MSU and CPP crystals.Expert opinion: Advances in molecular biology reveal that at the base of the inflammatory cascade, stimulated by MSU or CPP crystals, there are many complex cellular mechanisms mainly involving the NLRP3 inflammasome, the hallmark of autoinflammatory syndromes. The extensive studies carried out through in vitro and in vivo models along with a better clinical definition of the disease has led to an optimized use of existing drugs and the introduction of novel therapeutic strategies. In particular, the identification of IL-1 as the most important target in gout and pseudogout has made it possible to expand the pharmacological indications of anti-IL-1 biological drugs, opening new therapeutic perspectives for patients.

Identification of Potential Key Genes Involved in the Carotid Atherosclerosis

Purpose

Carotid atherosclerosis is a kind of systemic atherosclerosis in the carotid arteries. However, the efficiency of treatment is insufficient. Therefore, it is urgent to find therapeutic targets and deepen the understanding of carotid atherosclerosis.

Materials and Methods

In this study, we analyzed differentially expressed genes (DEGs) between atheroma plaque and macroscopically intact tissue (control samples). Furthermore, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genomes (KEGG) enrichment analysis based on the DEGs. Four methods were used to identify the hub genes in the protein–protein interaction networks of the DEGs. Furthermore, we also performed network module analysis to reveal carotid atherosclerosis-related gene modules and biological functions.

Results

The enrichment results showed that the biological functions were related to inflammation, immunity, chemokine and cell adhesion molecule, such as PIK-Akt signaling pathway, Rap1 signaling pathway, MAPK signaling pathway, NOD-like receptor signaling pathway and B cell receptor signaling pathway. In addition, we screened the hub genes. A total of 16 up-regulated genes (C3AR1, CCR1, CCR2, CD33, CD53, CXCL10, CXCL8, CXCR4, CYBB, FCER1G, FPR2, ITGAL, ITGAM, ITGAX, ITGB2, and LILRB2) were identified as hub genes. A total of 5 gene modules were obtained. We found that biological functions obtained for each cluster were mostly related to immunity, chemokines and cell adhesion molecules.

Conclusion

The present study identified key DEGs in atheroma plaque compared with control samples. The key genes involved in the development of carotid atherosclerosis may provide valuable therapeutic targets for carotid atherosclerosis.

Identification of key pathways and genes in carotid atherosclerosis through bioinformatics analysis of RNA-seq data

While acknowledging carotid atherosclerosis (CAS) as a risk factor for ischemic stroke, reports on its pathogenesis are scarce. This study aimed to explore the potential mechanism of CAS through RNA-seq data analysis. Carotid intima tissue samples from CAS patients and healthy subjects were subjected to RNA-seq analysis, which yielded, 1,427 differentially expressed genes (DEGs) related to CAS. Further, enrichment analysis (Gene Ontology, KEGG pathway, and MOCDE analysis) was performed on the DEGs. Hub genes identified via the protein-protein interaction network (PPI) were then analyzed using TRRUST, DisGeNET, PaGenBase, and CMAP databases. Results implicated inflammation and immunity in the pathogenesis of CAS. Also, lung disease was associated with CAS. Hub genes were expressed in multiple diseases, mainly regulated by RELA and NFKB1. Moreover, three small-molecule compounds were found via the CMAP database for management of CAS; hub genes served as potential targets. Collectively, inflammation and immunity are the potential pathological mechanisms of CAS. This study implicates CeForanide, Chenodeoxycholic acid, and 0317956-0000 as potential drug candidates for CAS treatment.

The clinical role of combined serum C1q and hsCRP in predicting coronary artery disease

OBJECTIVE

C1q has been shown to be associated with coronary heart disease (CAD) and can co-deposit with C-reactive protein (CRP) in atherosclerotic plaques. However, few studies have been conducted between C1q, CRP parameters and CAD. The aim of this study is to explore the relationship between C1q and CRP parameters and assess their clinical significance in CAD.

METHODS

238 total patients who underwent coronary artery angiography were enrolled and divided into control group (n = 65), stable CAD group (n = 47) and unstable angina group (UA group, n = 126). Patients' data were collected from self-administered questionnaires and electrical medical records. The severity of coronary stenosis was presented by Gensini score. The relationship between C1q, CRP parameters and CAD were evaluated by multivariate regression analysis and their predicting performance were assessed by ROC analysis and odds ratio analysis.

RESULTS

Compared with control group, C1q was showed significantly lower in stable CAD (P = 0.004) and UA groups (P = 0.008), while hsCRP was higher in UA group (P = 0.024). Serum C1q was weakly positively associated with hsCRP (r = 0.24, P < 0.001) but not correlated with Gensini score. Logistic regression identified C1q (OR: 0.87 per 10 mg/L, 95% CI: 0.79-0.95, P = 0.001) and hsCRP (OR: 1.08 mg/L, 95% CI: 1.01-1.15, P = 0.032) as independent determinants of CAD. Furthermore, combined C1q and hsCRP level showed higher discriminatory accuracy in predicting CAD than C1q (AUC: 0.676 vs 0.585, P = 0.101; NRI: 10.4%, P = 0.049; IDI: 3.9%, P < 0.001) or hsCRP (AUC: 0.676 vs 0.585, P = 0.101; NRI: 16.7%, P = 0.006; IDI: 5.8%, P < 0.001).

CONCLUSIONS

Reduced serum C1q and increased hsCRP are independently associated with CAD and could be potential predictors for CAD diagnosis. Furthermore, combined C1q and hsCRP showed better performance in predicting CAD than using single one.

Regulatory T cells induced by B cells suppress NLRP3 inflammasome activation and alleviate monosodium urate-induced gouty inflammation

Regulatory T cells induced by B cells (Treg-of-B cells), a distinct Foxp3^- Treg cell subset, have established the roles in the suppression of inflammatory conditions, including asthma and intestinal inflammation. However, little is known about the regulatory effects of Treg-of-B cells on innate immunity. Herein, we examined whether Treg-of-B cells could regulate macrophage function and prevent NLRP3-associated diseases, particularly inflammatory gouty arthritis. Treg-of-B cells, but not thymus-derived Treg or effector T cells, inhibited inflammasome-mediated IL-1β secretion, caspase-1 activation, and NLRP3 production by LPS/ATP stimulation in a cell contact-dependent manner. In addition, Treg-of-B cells inhibited monosodium urate-induced NLRP3 inflammasome activation in vitro via NF-κB signaling. Treg-of-B cells ameliorated gouty inflammation in a mouse air pouch model by reducing neutrophil and leukocyte influx and cytokine and chemokine production. Our results demonstrated that Treg-of-B cells exerted regulatory effects on innate immunity by suppressing NLRP3 inflammasome activation and feasible for future therapeutic applications.