Elevated circulating level of P2X7 receptor is related to severity of coronary artery stenosis and prognosis of acute myocardial infarction

Inhibition of the P2X7 receptor prevents atrial proarrhythmic remodeling in experimental post-operative atrial fibrillation

BACKGROUND

Post-operative atrial fibrillation (POAF) is a common complication in patients undergoing cardiac surgery. The purinergic receptor P2X7 (P2X7R) is involved in some cardiovascular diseases, whereas its effects on atrial fibrillation (AF) are unclear.

OBJECTIVE

This study was to assess the effect of P2X7R on atrial arrhythmogenic remodeling in the rat model of sterile pericarditis (SP).

METHODS

Male Sprague-Dawley (SD) rats were used to induce the SP model. Electrocardiogram, atrial electrophysiological protocol, histology, mRNA sequencing, real-time quantitative PCR, western blot, and Elisa assay were performed.

RESULTS

SP significantly up-regulated P2X7R expression; increased AF susceptibility; reduced the protein expression of ion channels including Nav1.5, Cav1.2, Kv4.2, Kv4.3, and Kv1.5; caused atrial fibrosis; increased norepinephrine (NE) level in plasma; promoted the production of inflammatory cytokines such as TNF-α, IL-1β, and IL-6; increased the accumulation of immune cells (CD68- and MPO- positive cells); and activated NLRP3 inflammasome signaling pathway. P2X7R antagonist Brilliant Blue G (BBG) mitigated SP-induced alterations. The mRNA sequencing demonstrated that BBG prevented POAF mainly by regulating the immune system. In addition, another selective P2X7R antagonist A740003, and IL-1R antagonist anakinra also reduced AF inducibility in the SP model.

CONCLUSIONS

P2X7R inhibition prevents SP-induced atrial proarrhythmic remodeling, which is closely associated with the improvement of inflammatory changes, ion channel expression, atrial fibrosis, and sympathetic activation. The findings point to P2X7R inhibition as a promising target for AF (particularly POAF) and perhaps other conditions.

Myocardial infarction complexity: A multi-omics approach

Myocardial infarction (MI), a prevalent cardiovascular disease, is fundamentally precipitated by thrombus formation in the coronary arteries, which subsequently decreases myocardial perfusion and leads to cellular necrosis. The intricacy of MI pathogenesis necessitates extensive research to elucidate the disease's root cause, thereby addressing the limitations present in its diagnosis and prognosis. With the continuous advancement of genomics technology, genomics, proteomics, metabolomics and transcriptomics are widely used in the study of MI, which provides an excellent way to identify new biomarkers that elucidate the complex mechanisms of MI. This paper provides a detailed review of various genomics studies of MI, including genomics, proteomics, transcriptomics, metabolomics and multi-omics studies. The metabolites and proteins involved in the pathogenesis of MI are investigated through integrated protein-protein interactions and multi-omics analysis by STRING and Metascape platforms. In conclusion, the future of omics research in myocardial infarction offers significant promise.

Bioinformatics analysis of potential common pathogenic mechanism for carotid atherosclerosis and Parkinson's disease

Background

Cerebrovascular disease (CVD) related to atherosclerosis and Parkinson's disease (PD) are two prevalent neurological disorders. They share common risk factors and frequently occur together. The aim of this study is to investigate the association between atherosclerosis and PD using genetic databases to gain a comprehensive understanding of underlying biological mechanisms.

Methods

The gene expression profiles of atherosclerosis (GSE28829 and GSE100927) and PD (GSE7621 and GSE49036) were downloaded from the Gene Expression Omnibus (GEO) database. After identifying the common differentially expressed genes (DEGs) for these two disorders, we constructed protein-protein interaction (PPI) networks and functional modules, and further identified hub genes using Least Absolute Shrinkage and Selection Operator (LASSO) regression. The diagnostic effectiveness of these hub genes was evaluated using Receiver Operator Characteristic Curve (ROC) analysis. Furthermore, we used single sample gene set enrichment analysis (ssGSEA) to analyze immune cell infiltration and explored the association of the identified hub genes with infiltrating immune cells through Spearman's rank correlation analysis in R software.

Results

A total of 50 shared DEGs, with 36 up-regulated and 14 down-regulated genes, were identified through the intersection of DEGs of atherosclerosis and PD. Using LASSO regression, we identified six hub genes, namely C1QB, CD53, LY96, P2RX7, C3, and TNFSF13B, in the lambda.min model, and CD14, C1QB, CD53, P2RX7, C3, and TNFSF13B in the lambda.1se model. ROC analysis confirmed that both models had good diagnostic efficiency for atherosclerosis datasets GSE28829 (lambda.min AUC = 0.99, lambda.1se AUC = 0.986) and GSE100927 (lambda.min AUC = 0.922, lambda.1se AUC = 0.933), as well as for PD datasets GSE7621 (lambda.min AUC = 0.924, lambda.1se AUC = 0.944) and GSE49036 (lambda.min AUC = 0.894, lambda.1se AUC = 0.881). Furthermore, we found that activated B cells, effector memory CD8 + T cells, and macrophages were the shared correlated types of immune cells in both atherosclerosis and PD.

Conclusion

This study provided new sights into shared molecular mechanisms between these two disorders. These common hub genes and infiltrating immune cells offer promising clues for further experimental studies to explore the common pathogenesis of these disorders.

Animal Models for the Investigation of P2X7 Receptors

The P2X7 receptor is a trimeric ligand-gated cation channel activated by extracellular adenosine 5'-triphosphate. The study of animals has greatly advanced the investigation of P2X7 and helped to establish the numerous physiological and pathophysiological roles of this receptor in human health and disease. Following a short overview of the P2X7 distribution, roles and functional properties, this article discusses how animal models have contributed to the generation of P2X7-specific antibodies and nanobodies (including biologics), recombinant receptors and radioligands to study P2X7 as well as to the pharmacokinetic testing of P2X7 antagonists. This article then outlines how mouse and rat models have been used to study P2X7. These sections include discussions on preclinical disease models, polymorphic P2X7 variants, P2X7 knockout mice (including bone marrow chimeras and conditional knockouts), P2X7 reporter mice, humanized P2X7 mice and P2X7 knockout rats. Finally, this article reviews the limited number of studies involving guinea pigs, rabbits, monkeys (rhesus macaques), dogs, cats, zebrafish, and other fish species (seabream, ayu sweetfish, rainbow trout and Japanese flounder) to study P2X7.

Purinergic receptor P2 × 7 contributes to abdominal aortic aneurysm development via modulating macrophage pyroptosis and inflammation

The purinergic receptor P2 × 7 has been established as an important mediator of inflammation and participates in a variety of cardiovascular diseases including atherosclerosis, however, its role in abdominal aortic aneurysms (AAA) remains unclear. In this study, we demonstrate that P2 × 7 plays essential roles in AAA development via modulating macrophage pyroptosis and inflammation. P2 × 7 is highly expressed in human AAA specimen, as well as in experimental murine AAA lesions (both CaCl₂-and Angiotensin Ⅱ-induced AAA models), and it mainly confines in macrophages. Furthermore, P2 × 7 deficiency or pharmacological inhibition with its antagonist could significantly attenuate aneurysm formation in experimental murine AAA models, while P2 × 7 agonist could promote AAA development. The caspase-I activity, matrix metalloproteinase (MMP) activity, reactive oxygen species (ROS) production and pro-inflammatory gene expression were significant reduced in experimental AAA lesions in mice with P2 × 7 deficiency or inhibition. Mechanistically, macrophage P2 × 7 can mediate the activation of NLRP3 inflammasome and activate its downstream caspase-1 to initiate the pyroptosis pathway. After caspase-1 activation, it further cleaves pro-interleukin (IL)-1β and gasdermin D (GSDMD). Consequently, the N-terminal fragment of GSDMD forms pores on the cell membrane, leading to macrophage pyroptosis and release of the pro-inflammatory factor IL-1β. The resulting vascular inflammation further leads to the upregulation of MMP and ROS, thereby promoting AAA development. In summary, these data identify P2 × 7-mediated macrophage pyroptosis signaling pathway as a novel contributory mechanism of AAA formation.

P2X7 Receptor-Mediated Inflammation in Cardiovascular Disease

Purinergic P2X7 receptor, a nonselective cation channel, is highly expressed in immune cells as well as cardiac smooth muscle cells and endothelial cells. Its activation exhibits to mediate nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3) inflammasome activation, resulting in the release of interleukin-1 beta (IL-1β) and interleukin-18 (IL-18), and pyroptosis, thus triggering inflammatory response. These pathological mechanisms lead to the deterioration of various cardiovascular diseases, including atherosclerosis, arrhythmia, myocardial infarction, pulmonary vascular remodeling, and cardiac fibrosis. All these worsening cardiac phenotypes are proven to be attenuated after the P2X7 receptor inhibition in experimental studies. The present review aimed to summarize key aspects of P2X7 receptor–mediated inflammation and pyroptosis in cardiovascular diseases. The main focus is on the evidence addressing the involvement of the P2X7 receptor in the inflammatory responses to the occurrence and development of cardiovascular disease and therapeutic interventions.

P2X7 Receptors: An Untapped Target for the Management of Cardiovascular Disease

Chronic low-grade inflammation contributes to the development of several diseases, including cardiovascular disease. Adequate strategies to target inflammation in cardiovascular disease are in their infancy and remain an avenue of great interest. The purinergic receptor P2X7 is a ubiquitously expressed receptor that predominately mediates inflammation and cellular death. P2X7 is a ligand-gated cation channel that is activated in response to high concentrations of extracellular ATP, triggering the assembly and activation of the NLRP3 (nuclear oligomerization domain like receptor family pyrin domain containing 3) inflammasome and subsequent release of proinflammatory cytokines IL (interleukin)-1β and IL-18. Increased P2X7 activation and IL-1β and IL-18 concentrations have been implicated in the development of many cardiovascular conditions including hypertension, atherosclerosis, ischemia/reperfusion injury, and heart failure. P2X7 receptor KO (knockout) mice exhibit a significant attenuation of the inflammatory response, which corresponds with reduced disease severity. P2X7 antagonism blunts blood pressure elevation in hypertension and progression of atherosclerosis in animal models. IL-1β and IL-18 inhibition has shown efficacy in clinical trials reducing major adverse cardiac events, including myocardial infarction, and heart failure. With several P2X7 antagonists available with proven safety margins, P2X7 antagonism could represent an untapped potential for therapeutic intervention in cardiovascular disorders.