NLRP3-Mediated Inflammation in Atherosclerosis and Associated Therapeutics

SET7 lysine methyltransferase mediates the up-regulation of NADPH oxidase expression, oxidative stress, and NLRP3 inflammasome priming in atherosclerosis

BACKGROUND

Dysregulation of histone methylation-based epigenetic mechanisms leads to either transient or long-lasting transcriptomic alterations in vascular and immune cells with important consequences on atherosclerotic plaque development and stability. We hypothesized that the epigenetic enzyme SET7 lysine methyltransferase contributes to the up-regulation of NADPH oxidase (Nox) and NLRP3 inflammasome expression in atherosclerosis.

METHODS

To test this hypothesis, we examined human non-atherosclerotic and atherosclerotic tissue samples, apolipoprotein E-deficient (ApoE-/-) mice, and human macrophages (Mac) employing real-time PCR, Western blot, immunofluorescence microscopy, and histological techniques. Male ApoE-/- mice with established atherosclerosis were randomized to receive concomitant with the high-fat diet, 5 mg/kg (R)-PFI-2, a selective SET7 pharmacological inhibitor, or its vehicle, every other day for 4 weeks.

RESULTS

The results revealed that SET7 mRNA and protein, and H3K4me1 levels were significantly elevated in human carotid atherosclerotic lesions, aorta of atherosclerotic mice, and in cultured pro-inflammatory Mac. In the atherosclerotic mice, pharmacological blockade of SET7 catalytic activity with the specific inhibitor, significantly reduced atherosclerotic plaque development, decreased the aortic up-regulation of mRNA and protein levels of Nox catalytic subunits, mitigated the formation of NT-/4HNE-protein adducts, attenuated NLRP3 gene and protein expression, and reduced pro-caspase-1 and pro-IL18 cleavage. In polarized pro-inflammatory human M1-Mac, SET7-oriented pharmacological intervention reduced the transcriptional up-regulation of Nox catalytic subunits, NLRP3, caspase-1, IL1β, and IL18, and the secretion IL1β and TNFα. Transient overexpression of SET7 in human endothelial cells enhanced mRNA levels of Nox1, Nox2, Nox4, Nox5, and p22phox.

CONCLUSION

The novel results show that SET7 regulates important mechanisms leading to enhanced formation of reactive oxygen species and pro-inflammatory cytokines release in atherosclerosis. The data recommend SET7 as a promising target for pharmacological interventions and as supportive therapeutic strategy in atherosclerotic cardiovascular diseases.

Mitochondrial DNA in atherosclerosis research progress: a mini review

Atherosclerosis (AS) is a chronic inflammatory disease that primarily affects large and medium-sized arteries and is one of the leading causes of death worldwide. This article reviews the multifaceted role of mitochondrial DNA (mtDNA) in AS, including its structure, function, release, and relationship with inflammation. Damage and release of mtDNA are considered central drivers in the development of AS, as they participate in the progression of AS by activating inflammatory pathways and affecting lipid metabolism. Therefore, therapeutic strategies targeting mtDNA and its downstream effects may provide new avenues to address this global health challenge.

The critical role of NLRP3 in drug resistance of cancers: Focus on the molecular mechanisms and possible therapeutics

Nod-like receptor protein 3 (NLRP3) is a member of the leucine-rich repeat-containing protein (NLR) canonical inflammasome family. It regulates the pathophysiology of cancer by facilitating immune responses and apoptotic proteins. Furthermore, it has been observed that chemotherapy activates NLRP3 in human malignancies. The secretion of IL-1β and IL-22 to promote cancer spread may be triggered by NLRP3 activation. Furthermore, earlier studies have exhibited that NLRP3 may cause medication resistance when used in cancer treatments given that cell viability may be regulated by NLRP3 depletion. Additionally, clinical studies have demonstrated correlation between NLRP3 expression, lymphogenesis, and cancer metastasis. Various NLRP3 agonists may cause the EMT process, stimulate IL-1β and Wnt/β-catenin signaling, and alter miRNA function in drug-resistant cells. This review seeks to clarify the possibility involvement of NLRP3-related pathways in the control of cancer cells' resistance to widely used treatment approaches, such as chemotherapy. In the end, an improved perception of the corresponding mechanisms behind NLRP3's tumor-supporting activities will help NLRP3-based treatments advance in the future.

The pleiotropic effects of PCSK9 in cardiovascular diseases beyond cholesterol metabolism

Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality globally, with elevated low-density lipoprotein cholesterol (LDL-C) levels being a major risk factor. Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a critical role in regulating LDL-C levels by promoting the degradation of hepatic low-density lipoprotein receptors (LDLR) responsible for clearing LDL-C from the circulation. PCSK9 inhibitors are novel lipid-modifying agents that have demonstrated remarkable efficacy in reducing plasma LDL-C levels and decreasing the incidence of CVD. However, the broader clinical impacts of PCSK9 functions beyond cholesterol metabolism, including both desired and undesired effects from therapeutic PCSK9 inhibition, underscore the urgent necessity to elucidate the underlying mechanisms. Recent studies have shown that local PCSK9 in the vascular system can interact with other receptors such as CD36, LRP-1, and ABCA1. This provides new evidence supporting the potential contribution of PCSK9 to CVD through LDLR-independent signaling pathways. Therefore, this review aimed to outline the diverse effects of PCSK9 on CVD and discuss the underlying mechanisms in non-cholesterol-related processes, which will provide a rational basis for its long-term pharmacological inhibition in the clinic.

Monocytic microRNAs-Novel targets in atherosclerosis therapy

Atherosclerosis is a chronic proinflammatory disease of the vascular wall resulting in narrowing of arteries due to plaque formation, thereby causing reduced blood supply that is the leading cause for diverse end-organ damage with high mortality rates. Monocytes/macrophages, activated by elevated circulating lipoproteins, are significantly involved in the formation and development of atherosclerotic plaques. The imbalance between proinflammatory and anti-inflammatory macrophages, arising from dysregulated macrophage polarization, appears to be a driving force in this process. Proatherosclerotic processes acting on monocytes/macrophages include accumulation of cholesterol in macrophages leading to foam cell formation, as well as dysfunctional efferocytosis, all of which contribute to the formation of unstable plaques. In recent years, microRNAs (miRs) were identified as factors that could modulate monocyte/macrophage function and may therefore interfere with the atherosclerotic process. In this review, we present effects of monocyte/macrophage-derived miRs on atherosclerotic processes in order to reveal new treatment options using miRmimics or antagomiRs. LINKED ARTICLES: This article is part of a themed issue Non-coding RNA Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v182.2/issuetoc.

Identification of key genes for cuproptosis in carotid atherosclerosis

Background

Atherosclerosis is a leading cause of cardiovascular disease worldwide, while carotid atherosclerosis (CAS) is more likely to cause ischemic cerebrovascular events. Emerging evidence suggests that cuproptosis may be associated with an increased risk of atherosclerotic cardiovascular disease. This study aims to explore the potential mechanisms linking cuproptosis and CAS.

Methods

The GSE100927 and GSE43292 datasets were merged to screen for CAS differentially expressed genes (DEGs) and intersected with cuproptosis-related genes to obtain CAS cuproptosis-related genes (CASCRGs). Unsupervised cluster analysis was performed on CAS samples to identify cuproptosis molecular clusters. Weighted gene co-expression network analysis was performed on all samples and cuproptosis molecule clusters to identify common module genes. CAS-specific DEGs were identified in the GSE100927 dataset and intersected with common module genes to obtain candidate hub genes. Finally, 83 machine learning models were constructed to screen hub genes and construct a nomogram to predict the incidence of CAS.

Results

Four ASCRGs (NLRP3, SLC31A2, CDKN2A, and GLS) were identified as regulators of the immune infiltration microenvironment in CAS. CAS samples were identified with two cuproptosis-related molecular clusters with significant biological function differences based on ASCRGs. 220 common module hub genes and 1,518 CAS-specific DEGs were intersected to obtain 58 candidate hub genes, and the machine learning model showed that the Lasso + XGBoost model exhibited the best discriminative performance. Further external validation of single gene differential analysis and nomogram identified SGCE, PCDH7, RAB23, and RIMKLB as hub genes; SGCE and PCDH7 were also used as biomarkers to characterize CAS plaque stability. Finally, a nomogram was developed to assess the incidence of CAS and exhibited satisfactory predictive performance.

Conclusions

Cuproptosis alters the CAS immune infiltration microenvironment and may regulate actin cytoskeleton formation.

Myocardial ischemia-reperfusion injury: The balance mechanism between mitophagy and NLRP3 inflammasome

Myocardial ischemia-reperfusion injury (MIRI) is an injury to cardiomyocytes due to restoration of blood flow after myocardial infarction (MI). It has recently gained much attention in clinical research with special emphasis on the roles of mitochondrial autophagy and inflammation. A mild inflammatory response promotes recovery of post-ischemic cardiomyocyte function and vascular regeneration, but a severe inflammatory response can cause irreversible and substantial cellular damage. Similarly, moderate mitochondrial autophagy can help inhibit excessive inflammation and protect cardiomyocytes. However, MIRI is aggravated when mitochondrial function is disrupted, such as inadequate clearance of damaged mitochondria or excessive activation of mitophagy. How to moderately control mitochondrial autophagy while promoting its balance with nucleotide-binding oligomerization structural domain receptor protein 3 (NLRP3) inflammasome activation is critical. In this paper, we reviewed the molecular mechanisms of mitochondrial autophagy and NLRP3 inflammasome, described the interaction between NLRP3 inflammasome and mitochondrial autophagy, and the effects of different signaling pathways and molecular proteins on MIRI, to provide a reference for future research.

PGC1α enhances macrophage efferocytosis in ox-LDL-stimulated RAW264.7 cells by regulating the NLRP3/PPARα axis

BACKGROUND

Defective clearance of apoptotic and foam cells achieved by arterial macrophage efferocytosis propels the progression of inflammatory atherosclerosis, but related molecular mechanisms in this process remain unclear. Herein, this study is engineered to probe into the mechanism of peroxisome-proliferator-activated receptor-γ coactivator-1α (PGC1α) on atherosclerosis.

METHODS

The PGC1α/NLR family pyrin domain containing 3 (NLRP3)/peroxisome proliferator activated receptor alpha (PPARα) axis in oxidized low-density lipoprotein (ox-LDL)-induced RAW264.7 cells was verified using Western blot. Inflammatory response, NLRP3 activation, efferocytotic efficiency and lipid uptake of the ox-LDL-stimulated cells overexpressing PGC1α or/and silencing PPARα were detected by enzyme-linked immunosorbent assay, immunofluorescence, tracing of apoptotic Jurkat cells and Oil red O staining.

RESULTS

PGC1α and PPARα levels were decreased, but NLRP3 level was increased in ox-LDL-stimulated RAW264.7 cells (P<0.001). PGC1α overexpression repressed the levels of IL-1β, IL-6 and TNF-α, NLRP3 expression or activation and foam cell formation (P<0.05), but enhanced efferocytosis as well as expressions of AXL, MERTK and TYRO3 in ox-LDL-stimulated cells (P<0.001). PGC1α overexpression increased PPARα expression. However, PPARα silencing reversed the effects of PGC1α overexpression on protecting macrophages against ox-LDL-induced inflammation, efferocytotic impairment and foam cell formation (P<0.05).

CONCLUSION

Overexpression PGC1α decreased NLRP3 activation to promoted the expression of PPARα, which alleviated the impairment of macrophage efferocytosis and inhibited the development of atherosclerosis development.

Unveiling the therapeutic potential of miR-146a: Targeting innate inflammation in atherosclerosis

Atherosclerosis is the foremost vascular disease, precipitating debilitating complications. Although therapeutic strategies have historically focused on reducing cholesterol deposition, recent insights emphasize the pivotal role of inflammation. Innate inflammation significantly contributes to plaque instability and rupture, underscoring the need for intervention across all disease stages. Numerous studies have highlighted the therapeutic potential of targeting innate immune pathways in atherosclerosis, revealing significant advancements in understanding the molecular mechanisms underlying inflammatory processes within arterial lesions. Notably, research has demonstrated that the modulation of microRNA-146a (miR-146a) expression impacts innate inflammation, effectively halts atherosclerosis progression, and enhances plaque stability by targeting interleukin-1 receptor-associated kinase (IRAK) and activating TNF receptor-associated factor 6 (TRAF6), a signalling pathway involving toll-like receptors (TLRs). Understanding the intricate mechanisms involved is crucial. This study provides a comprehensive analysis of the evidence and underlying mechanisms through which miR-146a exerts its effects. Integrating these findings into clinical practice may herald a transformative era in managing atherosclerotic cardiovascular disease.

Vascular restenosis following paclitaxel-coated balloon therapy is attributable to NLRP3 activation and LIN9 upregulation

Lower limb arterial occlusive disease is treated with intraluminal devices, such as paclitaxel (PTX)-coated balloons (PCBs); however, post-procedural restenosis remains a significant challenge. NLRP3 activation is known to play a significant role in atherosclerosis, but its involvement in restenosis following PCB intervention remains to be investigated. We identified that NLRP3 was differentially expressed in lower-limb arterial tissues sourced from healthy controls and patients with arterial occlusive disease. Through cell experiments, we confirmed that PTX is involved in the activation of NLRP3. Subsequently, we demonstrated that NLRP3 activation promotes the proliferation and migration of vascular smooth muscle cell (VSMC), thereby reducing their sensitivity to PTX. NLRP3 activation also stimulates the secretion of the inflammatory cytokine interleukin IL-1β. RNA sequencing of IL-1β-treated VSMC revealed the upregulation of BRD4 and LIN9. Further mechanistic investigations confirmed that IL-1β facilitates BRD4 recruitment, leading to enhanced LIN9 expression. The transcription factor LIN9 binds to the promoter region of the cell-cycle regulator AURKA, thereby promoting its transcription and subsequently upregulating the expression of the cell proliferation-associated molecule FOXM1. These processes ultimately mediate the proliferation, migration, and PTX resistance of VSMC. Additionally, we discovered that JQ1 inhibited the overexpression of the above molecules, and exhibited a synergistic effect with PTX. Our conclusions were validated through in vivo experiments in Sprague-Dawley rats. Collectively, our findings provide insights into the molecular mechanisms underlying restenosis following PCB therapy, and suggest that the combined use of JQ1 and PTX devices may represent a promising therapeutic strategy.

Crosstalk among mitophagy, pyroptosis, ferroptosis, and necroptosis in central nervous system injuries

Central nervous system injuries have a high rate of resulting in disability and mortality; however, at present, effective treatments are lacking. Programmed cell death, which is a genetically determined form of active and ordered cell death with many types, has recently attracted increasing attention due to its functions in determining the fate of cell survival. A growing number of studies have suggested that programmed cell death is involved in central nervous system injuries and plays an important role in the progression of brain damage. In this review, we provide an overview of the role of programmed cell death in central nervous system injuries, including the pathways involved in mitophagy, pyroptosis, ferroptosis, and necroptosis, and the underlying mechanisms by which mitophagy regulates pyroptosis, ferroptosis, and necroptosis. We also discuss the new direction of therapeutic strategies targeting mitophagy for the treatment of central nervous system injuries, with the aim to determine the connection between programmed cell death and central nervous system injuries and to identify new therapies to modulate programmed cell death following central nervous system injury. In conclusion, based on these properties and effects, interventions targeting programmed cell death could be developed as potential therapeutic agents for central nervous system injury patients.

The Relationship Between the Serum NLRP3 and Adiponectin Levels and Coronary Lesions in Patients with Unstable Angina with Type 2 Diabetes

Objective

To investigate the Levels of Nucleotide-binding, leucine-rich repeat and pyrin domain-containing protein 3 (NLRP3) and Adiponectin (APN) and their relationship with the severity of coronary artery disease in patients with Unstable Angina (UA) and Type 2 Diabetes (T2D).

Methods

Two hundred and thirty-one patients with UA were diagnosed by CAG in the Department of Cardiology of the Affiliated Hospital of Xuzhou Medical University from July 2022 to May 2023 were included, and 74 healthy subjects were included as the control group. The levels of NLRP3 and APN in each group were detected by ELISA and the Gensini score in each patient according to the results of CAG. The correlations between NLRP3, APN, and Gensini score were analyzed. According to whether complicated with T2D or not, we further analyze the effect of NLRP3 and APN levels of patients with UA and T2D on the severity of coronary artery stenosis.

Results

The levels of NLRP3 in UA with T2D group were the highest, followed by simple UA group, and the lowest in the control group, and the level of APN was the opposite. Spearman Correlation analysis showed that the level of NLRP3 was positively correlated with Gensini score (ρ1=0.688, P<0.05) and the level of APN was negatively associated with Gensini score (ρ2= -0.515, P<0.05). There was a negative correlation between NLRP3 and the level of APN (ρ3= -0.366, P<0.05). High NLRP3 and low APN levels are the risk factors for atherosclerosis.

Conclusion

The NLRP3 and APN were abnormally expressed in patients with UA complicated with T2D. With the aggravation of atherosclerosis, the level of NLRP3 increased and the level of APN decreased.

The role of the NLRP3 inflammasome in atherosclerotic disease: Systematic review and meta-analysis

Atherosclerosis is a chronic, progressive cardiovascular disease characterized by cholesterol deposition within blood vessel walls. Recent literature has suggested that the NLRP3 [NOD (nucleotide oligomerization domain)-, LRR (leucine-rich repeat)-, and PYD (pyrin domain)-containing protein 3] inflammasome is a key mediator in the development, progression, and destabilization of atherosclerotic plaques. This review aims to evaluate the current literature on the role of NLRP3 in human atherosclerosis. This systematic review was registered on the PROSPERO database (ID = CRD42022340039) and involved the search of a total of 8 databases. Records were screened in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. A total of 20 studies were included and quality assessed using the NIH: NHLBI tool. Six were eligible for meta-analysis using RevMan 5.4.1. We identified 20 relevant articles representing 3388 participants. NLRP3 mRNA levels and downstream cytokines, interleukin (IL)-1β and IL-18 were found to be associated with atherosclerotic disease. Fold changes in NLRP3 mRNA levels were most strongly associated with high risk atherosclerotic disease, compared to controls [0.84 (95 % CI: 0.41-1.28)]. IL-1β mRNA fold change was more robustly associated with high-risk atherosclerotic disease [0.61 (95 % CI: 0.10-1.13)] than IL-18 [0.47 (95 % CI: 0.02-0.91)]. NLRP3, IL-1β, and IL-18 are associated with high-risk atherosclerotic disease. However, given the scope of this review, the role of this inflammasome and its cytokine counterparts in acting as prognosticators of coronary artery disease severity is unclear. Several upstream activators such as cholesterol crystals are involved in the canonical or non-canonical activation of the NLRP3 inflammasome and its downstream cytokines. These findings highlight the necessity for further research to delineate the exact mechanisms of NLRP3 inflammasome activation and potential drug targets.

Modulation of atherosclerosis-related signaling pathways by Chinese herbal extracts: Recent evidence and perspectives

Atherosclerotic cardiovascular disease remains a preeminent cause of morbidity and mortality globally. The onset of atherosclerosis underpins the emergence of ischemic cardiovascular diseases, including coronary heart disease (CHD). Its pathogenesis entails multiple factors such as inflammation, oxidative stress, apoptosis, vascular endothelial damage, foam cell formation, and platelet activation. Furthermore, it triggers the activation of diverse signaling pathways including Phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt), NF-E2-related factor 2/antioxidant response element (Nrf2/ARE), the Notch signaling pathway, peroxisome proliferator-activated receptor (PPAR), nucleotide oligo-structural domain-like receptor thermoprotein structural domain-associated protein 3 (NLRP3), silencing information regulator 2-associated enzyme 1 (Sirt1), nuclear transcription factor-κB (NF-κB), Circular RNA (Circ RNA), MicroRNA (mi RNA), Transforming growth factor-β (TGF-β), and Janus kinase-signal transducer and activator of transcription (JAK/STAT). Over recent decades, therapeutic approaches for atherosclerosis have been dominated by the utilization of high-intensity statins to reduce lipid levels, despite significant adverse effects. Consequently, there is a growing interest in the development of safer and more efficacious drugs and therapeutic modalities. Traditional Chinese medicine (TCM) offers a vital strategy for the prevention and treatment of cardiovascular diseases. Numerous studies have detailed the mechanisms through which TCM active ingredients modulate signaling molecules and influence the atherosclerotic process. This article reviews the signaling pathways implicated in the pathogenesis of atherosclerosis and the advancements in research on TCM extracts for prevention and treatment, drawing on original articles from various databases including Google Scholar, Medline, CNKI, Scopus, and Pubmed. The objective is to furnish a reference for the clinical management of cardiovascular diseases.

Photodynamic Therapy for Atherosclerosis: Past, Present, and Future

This review paper examines the evolution of photodynamic therapy (PDT) as a novel, minimally invasive strategy for treating atherosclerosis, a leading global health concern. Atherosclerosis is characterized by the accumulation of lipids and inflammation within arterial walls, leading to significant morbidity and mortality through cardiovascular diseases such as myocardial infarction and stroke. Traditional therapeutic approaches have primarily focused on modulating risk factors such as hypertension and hyperlipidemia, with emerging evidence highlighting the pivotal role of inflammation. PDT, leveraging a photosensitizer, specific-wavelength light, and oxygen, offers targeted treatment by inducing cell death in diseased tissues while sparing healthy ones. This specificity, combined with advancements in nanoparticle technology for improved delivery, positions PDT as a promising alternative to traditional interventions. The review explores the mechanistic basis of PDT, its efficacy in preclinical studies, and the potential for enhancing plaque stability and reducing macrophage density within plaques. It also addresses the need for further research to optimize treatment parameters, mitigate adverse effects, and validate long-term outcomes. By detailing past developments, current progress, and future directions, this paper aims to highlight PDT's potential in revolutionizing atherosclerosis treatment, bridging the gap from experimental research to clinical application.

Integrated Proteomics Characterization of NLRP3 Inflammasome Inhibitor MCC950 in Monocytic Cell Line Confirms Direct MCC950 Engagement with Endogenous NLRP3

Inhibition of the NLRP3 inflammasome is a promising strategy for the development of new treatments for inflammatory diseases. MCC950 is a potent and selective small-molecule inhibitor of the NLRP3 pathway and has been validated in numerous species and disease models. Although the capacity of MCC950 to block NLRP3 signaling is well-established, it is still critical to identify the mechanism of action and molecular targets of MCC950 to inform and derisk drug development. Quantitative proteomics performed in disease-relevant systems provides a powerful method to study both direct and indirect pharmacological responses to small molecules to elucidate the mechanism of action and confirm target engagement. A comprehensive target deconvolution campaign requires the use of complementary chemical biology techniques. Here we applied two orthogonal chemical biology techniques: compressed Cellular Thermal Shift Assay (CETSA) and photoaffinity labeling chemoproteomics, performed under biologically relevant conditions with LPS-primed THP-1 cells, thereby deconvoluting, for the first time, the molecular targets of MCC950 using chemical biology techniques. In-cell chemoproteomics with inlysate CETSA confirmed the suspected mechanism as the disruption of inflammasome formation via NLRP3. Further cCETSA (c indicates compressed) in live cells mapped the stabilization of NLRP3 inflammasome pathway proteins, highlighting modulation of the targeted pathway. This is the first evidence of direct MCC950 engagement with endogenous NLRP3 in a human macrophage cellular system using discovery proteomics chemical biology techniques, providing critical information for inflammasome studies.

Fantastic voyage: The journey of NLRP3 inflammasome activation

NLRP3 inflammasome, an intracellular multiprotein complex, can be activated by a range of pathogenic microbes or endogenous hazardous chemicals. Its activation results in the release of cytokines such as IL-1β and IL-18, as well as Gasdermin D which eventually causes pyroptosis. The activation of NLRP3 inflammasome is under strict control and regulation by numerous pathways and mechanisms. Its excessive activation can lead to a persistent inflammatory response, which is linked to the onset and progression of severe illnesses. Recent studies have revealed that the subcellular localization of NLRP3 changes significantly during the activation process. In this review, we review the current understanding of the molecular mechanism of NLRP3 inflammasome activation, focusing on the subcellular localization of NLRP3 and the associated regulatory mechanisms. We aim to provide a comprehensive understanding of the dynamic transportation, activation, and degradation processes of NLRP3.

Bergamot Byproducts: A Sustainable Source to Counteract Inflammation

Chronic inflammation is the result of an acute inflammatory response that fails to eliminate the pathogenic agent or heal the tissue injury. The consequence of this failure lays the foundations to the onset of several chronic ailments, including skin disorders, respiratory and neurodegenerative diseases, metabolic syndrome, and, eventually, cancer. In this context, the long-term use of synthetic anti-inflammatory drugs to treat chronic illnesses cannot be tolerated by patients owing to the severe side effects. Based on this, the need for novel agents endowed with anti-inflammatory effects prompted to search potential candidates also within the plant kingdom, being recognized as a source of molecules currently employed in several therapeutical areas. Indeed, the ever-growing evidence on the anti-inflammatory properties of dietary polyphenols traced the route towards the study of flavonoid-rich sources, such as Citrus bergamia (bergamot) and its derivatives. Interestingly, the recent paradigm of the circular economy has promoted the valorization of Citrus fruit waste and, in regard to bergamot, it brought to light new evidence corroborating the anti-inflammatory potential of bergamot byproducts, thus increasing the scientific knowledge in this field. Therefore, this review aims to gather the latest literature supporting the beneficial role of both bergamot derivatives and waste products in different models of inflammatory-based diseases, thus highlighting the great potentiality of a waste re-evaluation perspective.

To re-examine the intersection of microglial activation and neuroinflammation in neurodegenerative diseases from the perspective of pyroptosis

Neurodegenerative diseases (NDs), such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and motor neuron disease, are diseases characterized by neuronal damage and dysfunction. NDs are considered to be a multifactorial disease with diverse etiologies (immune, inflammatory, aging, genetic, etc.) and complex pathophysiological processes. Previous studies have found that neuroinflammation and typical microglial activation are important mechanisms of NDs, leading to neurological dysfunction and disease progression. Pyroptosis is a new mode involved in this process. As a form of programmed cell death, pyroptosis is characterized by the expansion of cells until the cell membrane bursts, resulting in the release of cell contents that activates a strong inflammatory response that promotes NDs by accelerating neuronal dysfunction and abnormal microglial activation. In this case, abnormally activated microglia release various pro-inflammatory factors, leading to the occurrence of neuroinflammation and exacerbating both microglial and neuronal pyroptosis, thus forming a vicious cycle. The recognition of the association between pyroptosis and microglia activation, as well as neuroinflammation, is of significant importance in understanding the pathogenesis of NDs and providing new targets and strategies for their prevention and treatment.

Phosphatidylethanolamine alleviates OX-LDL-induced macrophage inflammation by upregulating autophagy and inhibiting NLRP1 inflammasome activation

Oxidized low-density lipoprotein (OX-LDL)-induced inflammation and autophagy dysregulation are important events in the progression of atherosclerosis. Phosphatidylethanolamine (PE), a multifunctional phospholipid that is enriched in cells, has been proven to be directly involved in autophagy which is closely associated with inflammation. However, whether PE can influence OX-LDL-induced autophagy dysregulation and inflammation has not been reported. In the present study, we revealed that OX-LDL significantly induced macrophage inflammation through the CD36-NLRP1-caspase-1 signaling pathway in fish. Meanwhile, cellular PE levels were significantly decreased in response to OX-LDL induction. Based on the relationship between PE and autophagy, we then examined the effect of PE supplementation on OX-LDL-mediated autophagy impairment and inflammation induction in macrophages. As expected, exogenous PE restored impaired autophagy and alleviated inflammation in OX-LDL-stimulated cells. Notably, autophagy inhibitors reversed the inhibitory effect of PE on OX-LDL-induced maturation of IL-1β, indicating that the regulation of PE on OX-LDL-induced inflammation is dependent on autophagy. Furthermore, the positive effect of PE on OX-LDL-induced inflammation was relatively conserved in mouse and fish macrophages. In conclusion, we elucidated the role of the CD36-NLRP1-caspase-1 signaling pathway in OX-LDL-induced inflammation in fish and revealed for the first time that altering PE abundance in OX-LDL-treated cells could alleviate inflammasome-mediated inflammation by inducing autophagy. Given the relationship between OX-LDL-induced inflammation and atherosclerosis, this study prompts that the use of PE-rich foods promises to be a new strategy for atherosclerosis treatment in vertebrates.

Role of the NLRP3 inflammasome in gynecological disease

The NLR family pyrin domain containing 3 (NLRP3) inflammasome is involved in the innate immune system and is a three-part macromolecular complex comprising the NLRP3 protein, apoptosis-associated speck-like protein containing a CARD (ASC) and the cysteine protease pro-caspase-1. When the NLRP3 inflammasome is activated, it can produce interleukin (IL)- 1β and IL-18 and eventually lead to inflammatory cell pyroptosis. Related studies have demonstrated that the NLRP3 inflammasome can induce an immune response and is related to the occurrence and development of gynecological diseases, such as endometriosis, polycystic ovary syndrome and breast cancer. NLRP3 inflammasome inhibitors are beneficial for maintaining cellular homeostasis and tissue health and have been found effective in targeting some gynecological diseases. However, excessive inhibitor concentrations have been found to cause adverse effects. Therefore, proper control of NLRP3 inflammasome activity is critical. This paper summarizes the structure and function of the NLRP3 inflammasome and highlights the therapeutic potential of targeting it in gynecological diseases, such as endometriosis, polycystic ovary syndrome and breast cancer The application of NLRP3 inflammasome inhibitors is also discussed.

Molecular and cellular mechanisms of inflammation in atherosclerosis

Atherosclerosis and its complications are a major cause of morbidity and mortality worldwide in spite of the improved medical and invasive treatment in terms of revascularization. Atherosclerosis is a dynamic, multi-step process in which inflammation is a ubiquitous component participating in the initiation, development, and entanglements of the atherosclerotic plaque. After activation, the immune system, either native or acquired, is part of the atherosclerotic dynamics enhancing the pro-atherogenic function of immune or non-immune cells, such as endothelial cells, smooth muscle cells, or platelets, through mediators such as cytokines or directly by cell-to-cell interaction. Cytokines are molecules secreted by the activated cells mentioned above that mediate the inflammatory component of atherosclerosis whose function is to stimulate the immune cells and the production of further cytokines. This review provides insights of the cell axis activation and specific mechanisms and pathways through which inflammation actuates atherosclerosis.

Unbalanced Redox With Autophagy in Cardiovascular Disease

Precise redox balance is essential for the optimum health and physiological function of the human body. Furthermore, an unbalanced redox state is widely believed to be part of numerous diseases, ultimately resulting in death. In this review, we discuss the relationship between redox balance and cardiovascular disease (CVD). In various animal models, excessive oxidative stress has been associated with increased atherosclerotic plaque formation, which is linked to the inflammation status of several cell types. However, various antioxidants can defend against reactive oxidative stress, which is associated with an increased risk of CVD and mortality. The different cardiovascular effects of these antioxidants are presumably due to alterations in the multiple pathways that have been mechanistically linked to accelerated atherosclerotic plaque formation, macrophage activation, and endothelial dysfunction in animal models of CVD, as well as in in vitro cell culture systems. Autophagy is a regulated cell survival mechanism that removes dysfunctional or damaged cellular organelles and recycles the nutrients for the generation of energy. Furthermore, in response to atherogenic stress, such as the generation of reactive oxygen species, oxidized lipids, and inflammatory signaling between cells, autophagy protects against plaque formation. In this review, we characterize the broad spectrum of oxidative stress that influences CVD, summarize the role of autophagy in the content of redox balance-associated pathways in atherosclerosis, and discuss potential therapeutic approaches to target CVD by stimulating autophagy.

Normothermic ex vivo heart perfusion with NLRP3 inflammasome inhibitor Mcc950 treatment improves cardiac function of circulatory death hearts after transplantation

Background

The utilization of donation after circulatory death (DCD) hearts can enlarge the donor pool. However, DCD hearts suffer from serious ischemia/reperfusion injury (IRI). Recent studies found that the activation of NLRP3 inflammasome could play a significant role in organ IRI. Mcc950, which is a novel inhibitor of the NLRP3 inflammasome, can be applied to treat various kinds of cardiovascular diseases. Therefore, we hypothesized that the treatment of mcc950 could protect DCD hearts preserved with normothermic ex vivo heart perfusion (EVHP) against myocardial IRI via inhibiting NLRP3 inflammasome in a rat heart transplantation model of DCD.

Methods

Donor-heart rats were randomly divided into four groups: Control group; Vehicle group; MP-mcc950 group; and MP + PO-mcc950 group. Mcc950 was added into the perfusate of normothermic EVHP in the MP-mcc950 and MP + PO-mcc950 groups, and was injected into the left external jugular vein after heart transplantation in the MP + PO-mcc950 group. Cardiac functional assessment was performed. The level of oxidative stress, inflammatory response, apoptosis, and NLRP3 inflammasome-associated protein of donor hearts were evaluated.

Results

The treatment with mcc950 significantly increased the developed pressure (DP), dP/dtmax, and dP/dtmin of the left ventricular of DCD hearts at 90 min after heart transplantation in both MP-mcc950 and MP + PO-mcc950 groups. Furthermore, mcc950 added into perfusate and injected after transplantation in both MP-mcc950 and MP + PO-mcc950 groups significantly attenuated the level of oxidative stress, inflammatory response, apoptosis, and NLRP3 inflammasome compared with the vehicle group.

Conclusions

Normothermic EVHP combined with mcc950 treatment can be a promising and novel DCD heart preservation strategy, which can alleviate myocardial IRI via inhibiting NLRP3 inflammasome.