Targeting the PANoptosome with 3,4-Methylenedioxy-β-Nitrostyrene, Reduces PANoptosis and Protects the Kidney against Renal İschemia-Reperfusion Injury

The mechanosensitive Piezo1 channel exacerbates myocardial ischaemia/reperfusion injury by activating caspase-8-mediated PANoptosis

PANoptosis is a newly discovered type of cell death characterized by pyroptosis, apoptosis and/or necroptosis and has been implicated in the inflammatory response. Piezo1 is a mechanosensitive ion channel that plays important roles in physiological development and various diseases. However, whether cardiomyocytes undergo PANoptosis during myocardial ischaemia/reperfusion (I/R) injury and the role of Piezo1 in this process remain largely unexplored. In this study, our results revealed that the expression levels of the main components of the PANoptosome, including caspase-8, caspase-3, NLRP3, caspase-1, GSDMD, RIPK1, RIPK3 and MLKL, were significantly upregulated in I/R heart tissues over time, indicating the occurrence of PANoptosis in I/R hearts. Accordingly, Piezo1 expression was significantly upregulated in I/R-injured hearts and hypoxia/reoxygenation (H/R)-treated cardiomyocytes. In contrast, pharmacological inhibition of Piezo1 by the inhibitor GsMTx4 in mice markedly attenuated the I/R-mediated decline in cardiac contractile function and increases in infarct size, apoptosis, oxidative stress and inflammation accompanied by the inhibition of PANoptosis-related mediators in I/R hearts. Consistently, the effects of Piezo1 on calcium influx and PANoptosis were further verified by GsMTx4 and Piezo1 activator Yoda1 in H/R-treated cardiomyocytes in vitro. Moreover, caspase-8 rather than calcium influx was required for H/R-induced PANoptosis in vitro. Mechanistically, Piezo1 interacts with caspase-8, a key initial activator of the PANoptosome complex, which subsequently activates cardiomyocyte PANoptosis, leading to cardiac dysfunction. In summary, these data suggest that Piezo1 is a new cardiac mechanosensor that promotes cardiac I/R injury possibly through the caspase-8-mediated activation of cardiomyocyte PANoptosis and highlight that Piezo1 may represent a new target for treating ischaemic heart disease.

Lycopene Protects against Atrazine-Induced Kidney STING-Dependent PANoptosis through Stabilizing mtDNA via Interaction with Sam50/PHB1

Atrazine (ATR) is a widely used herbicide worldwide that can cause kidney damage in humans and animals by accumulation in water and soil. Lycopene (LYC), a carotenoid with numerous biological activities, plays an important role in kidney protection due to its potent antioxidant and anti-inflammatory effects. The current study sought to investigate the role of interactions between mtDNA and the cGAS-STING signaling pathway in LYC mitigating PANoptosis and inflammation in kidneys induced by ATR exposure. In our research, 350 mice were orally administered LYC (5 mg/kg BW/day) and ATR (50 or 200 mg/kg BW/day) for 21 days. Our results reveal that ATR exposure induces a decrease in mtDNA stability, resulting in the release of mtDNA into the cytoplasm through the mPTP pore and the BAX pore and the mobilization of the cGAS-STING pathway, thereby inducing renal PANoptosis and inflammation. LYC can inhibit the above changes caused by ATR. In conclusion, LYC inhibited ATR exposure-induced histopathological changes, renal PANoptosis, and inflammation by inhibiting the cGAS-STING pathway. Our results demonstrate the positive role of LYC in ATR-induced renal injury and provide a new therapeutic target for treating renal diseases in the clinic.

PANoptosis-like death in acute-on-chronic liver failure injury

The pathogenesis of Acute-on-chronic liver failure (ACLF) involves several forms of cell death, such as pyroptosis, apoptosis, and necroptosis, which consist of PANoptosis. To explore PANoptosis as a regulated cell death pathway in ACLF. Firstly, a bioinformatic strategy was used to observe the role of the PANoptosis pathway in ACLF and identify differentially expressed genes related to PANoptosis. Enrichment analysis showed that PANoptosis-related pathways were up-regulated in ACLF. We screened out BAX from the intersection of pyroptosis, apoptosis, necroptosis, and DEGs. Secondly, we screened articles from literature databases related to PANoptosis and liver failure, and specific forms of PANoptosis were reported in different experimental models in vitro and in vivo. Secondly, we established a model of ACLF using carbon tetrachloride-induced liver fibrosis, followed by D-galactosamine and lipopolysaccharide joint acute attacks. A substantial release of inflammatory factors(IL-6, IL-18, TNFα, and IFNγ) and the key proteins of PANoptosis (NLRP3, CASP1, GSDMD, BAX, CASP8, CASP3, CASP7, and MLKL) were detected independently in the ACLF rats. Finally, we found that combining TNF-α/INF-γ inflammatory cytokines could induce L02 cells PANoptosis. Our study highlighted the potential role of ACLF and helps drug discovery targeting PANoptosis in the future.

Therapeutic potential of PANoptosis: innate sensors, inflammasomes, and RIPKs in PANoptosomes

The innate immune system initiates cell death pathways in response to pathogens and cellular stress. Cell death can be either non-lytic (apoptosis) or lytic (PANoptosis, pyroptosis, and necroptosis). PANoptosis has been identified as an inflammatory, lytic cell death pathway driven by caspases and RIPKs that is regulated by PANoptosome complexes, making it distinct from other cell death pathways. Several PANoptosome complexes (including ZBP1-, AIM2-, RIPK1-, and NLRP12-PANoptosomes) have been characterized to date. Furthermore, PANoptosis is implicated in infectious and inflammatory diseases, cancers, and homeostatic perturbations. Therefore, targeting its molecular components offers significant potential for therapeutic development. This review covers PANoptosomes and their assembly, PANoptosome-mediated cell death mechanisms, and ongoing progress in developing therapeutics that target PANoptosis.

PANoptosis: Mechanisms, biology, and role in disease

Cell death can be executed through distinct subroutines. PANoptosis is a unique inflammatory cell death modality involving the interactions between pyroptosis, apoptosis, and necroptosis, which can be mediated by multifaceted PANoptosome complexes assembled via integrating components from other cell death modalities. There is growing interest in the process and function of PANoptosis. Accumulating evidence suggests that PANoptosis occurs under diverse stimuli, for example, viral or bacterial infection, cytokine storm, and cancer. Given the impact of PANoptosis across the disease spectrum, this review briefly describes the relationships between pyroptosis, apoptosis, and necroptosis, highlights the key molecules in PANoptosome formation and PANoptosis activation, and outlines the multifaceted roles of PANoptosis in diseases together with a potential for therapeutic targeting. We also discuss important concepts and pressing issues for future PANoptosis research. Improved understanding of PANoptosis and its mechanisms is crucial for identifying novel therapeutic targets and strategies.

Mechanisms of PANoptosis and relevant small-molecule compounds for fighting diseases

Pyroptosis, apoptosis, and necroptosis are mainly programmed cell death (PCD) pathways for host defense and homeostasis. PANoptosis is a newly distinct inflammatory PCD pathway that is uniquely regulated by multifaceted PANoptosome complexes and highlights significant crosstalk and coordination among pyroptosis (P), apoptosis (A), and/or necroptosis(N). Although some studies have focused on the possible role of PANpoptosis in diseases, the pathogenesis of PANoptosis is complex and underestimated. Furthermore, the progress of PANoptosis and related agonists or inhibitors in disorders has not yet been thoroughly discussed. In this perspective, we provide perspectives on PANoptosome and PANoptosis in the context of diverse pathological conditions and human diseases. The treatment targeting on PANoptosis is also summarized. In conclusion, PANoptosis is involved in plenty of disorders including but not limited to microbial infections, cancers, acute lung injury/acute respiratory distress syndrome (ALI/ARDS), ischemia-reperfusion, and organic failure. PANoptosis seems to be a double-edged sword in diverse conditions, as PANoptosis induces a negative impact on treatment and prognosis in disorders like COVID-19 and ALI/ARDS, while PANoptosis provides host protection from HSV1 or Francisella novicida infection, and kills cancer cells and suppresses tumor growth in colorectal cancer, adrenocortical carcinoma, and other cancers. Compounds and endogenous molecules focused on PANoptosis are promising therapeutic strategies, which can act on PANoptosomes-associated members to regulate PANoptosis. More researches on PANoptosis are needed to better understand the pathology of human conditions and develop better treatment.

Pyroptosis in cardiovascular diseases: Pumping gasdermin on the fire

Pyroptosis is a form of programmed cell death associated with activation of inflammasomes and inflammatory caspases, proteolytic cleavage of gasdermin proteins (forming pores in the plasma membrane), and selective release of proinflammatory mediators. Induction of pyroptosis results in amplification of inflammation, contributing to the pathogenesis of chronic cardiovascular diseases such as atherosclerosis and diabetic cardiomyopathy, and acute cardiovascular events, such as thrombosis and myocardial infarction. While engagement of pyroptosis during sepsis-induced cardiomyopathy and septic shock is expected and well documented, we are just beginning to understand pyroptosis involvement in the pathogenesis of cardiovascular diseases with less defined inflammatory components, such as atrial fibrillation. Due to the danger that pyroptosis represents to cells within the cardiovascular system and the whole organism, multiple levels of pyroptosis regulation have evolved. Those include regulation of inflammasome priming, post-translational modifications of gasdermins, and cellular mechanisms for pore removal. While pyroptosis in macrophages is well characterized as a dramatic pro-inflammatory process, pyroptosis in other cell types within the cardiovascular system displays variable pathways and consequences. Furthermore, different cells and organs engage in local and distant crosstalk and exchange of pyroptosis triggers (oxidized mitochondrial DNA), mediators (IL-1β, S100A8/A9) and antagonists (IL-9). Development of genetic tools, such as Gasdermin D knockout animals, and small molecule inhibitors of pyroptosis will not only help us fully understand the role of pyroptosis in cardiovascular diseases but may result in novel therapeutic approaches inhibiting inflammation and progression of chronic cardiovascular diseases to reduce morbidity and mortality from acute cardiovascular events.

PANoptosis: A Cell Death Characterized by Pyroptosis, Apoptosis, and Necroptosis

PANoptosis is a new cell death proposed by Malireddi et al in 2019, which is characterized by pyroptosis, apoptosis and necroptosis, but cannot be explained by any of them alone. The interaction between pyroptosis, apoptosis and necroptosis is involved in PANoptosis. In this review, from the perspective of PANoptosis, we focus on the relationship between pyroptosis, apoptosis and necroptosis, the key molecules in the process of PANoptosis and the formation of PANoptosome, as well as the role of PANoptosis in diseases. We aim to understand the mechanism of PANoptosis and provide a basis for targeted intervention of PANoptosis-related molecules to treat human diseases.