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

Dachengqi decoction dispensing granule ameliorates LPS-induced acute lung injury by inhibiting PANoptosis in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Acute lung injury (ALI) is a serious health-threatening syndrome of intense inflammatory response in the lungs, with progression leading to acute respiratory distress syndrome (ARDS). Dachengqi decoction dispensing granule (DDG) has a pulmonary protective role, but its potential modulatory mechanism to alleviate ALI needs further excavation.

AIM OF THE STUDY

This study aims to investigate the effect and potential mechanism of DDG on lipopolysaccharide (LPS)-induced ALI models in vivo and in vitro.

MATERIALS AND METHODS

LPS-treated Balb/c mice and BEAS-2B cells were used to construct in vivo and in vitro ALI models, respectively. Hematoxylin-eosin (HE), Wet weight/Dry weight (W/D) calculation of lung tissue, and total protein and Lactic dehydrogenase (LDH) assays in BALF were performed to assess the extent of lung tissue injury and pulmonary edema. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and interleukin-18 (IL-18) in BALF, serum, and cell supernatant. The qRT-PCR was used to detect inflammatory factors, Z-DNA binding protein 1 (ZBP1), and receptor-interacting protein kinase 1 (RIPK1) expression in lung tissues and BEAS-2B cells. Double immunofluorescence staining and co-immunoprecipitation were used to detect the relative expression and co-localization of ZBP1 and RIPK1. The effects of LPS and DDG on BEAS-2B cell activity were detected by Cell Counting Kit-8 (CCK-8). Western blot (WB) was performed to analyze the expression of PANoptosis-related proteins in lung tissues and BEAS-2B cells.

RESULTS

In vivo, DDG pretreatment could dose-dependently improve the pathological changes of lung tissue in ALI mice, and reduce the W/D ratio of lung, total protein concentration, and LDH content in BALF. In vitro, DDG reversed the inhibitory effect of LPS on BEAS-2B cell viability. Meanwhile, DDG significantly reduced the levels of inflammatory factors in vitro and in vivo. In addition, DDG could inhibit the expression levels of PANoptosis-related proteins, especially the upstream key regulatory molecules ZBP1 and RIPK1.

CONCLUSION

DDG could inhibit excessive inflammation and PANoptosis to alleviate LPS-induced ALI, thus possessing good anti-inflammatory and lung-protective effects. This study establishes a theoretical basis for the further development of DDG and provides a new prospect for ALI treatment by targeting PANoptosis.

Nitric oxide-based multi-synergistic nanomedicine: an emerging therapeutic for anticancer

Gas therapy has emerged as a promising approach for treating cancer, with gases like NO, H2S, and CO showing positive effects. Among these, NO is considered a key gas molecule with significant potential in stopping cancer progression. However, due to its high reactivity and short half-life, delivering NO directly to tumors is crucial for enhancing cancer treatment. NO-driven nanomedicines (NONs) have been developed to effectively deliver NO donors to tumors, showing great progress in recent years. This review provides an overview of the latest advancements in NO-based cancer nanotherapeutics. It discusses the types of NO donors used in current research, the mechanisms of action behind NO therapy for cancer, and the different delivery systems for NO donors in nanotherapeutics. It also explores the potential of combining NO donors with other treatments for enhanced cancer therapy. Finally, it examines the future prospects and challenges of using NONs in clinical settings for cancer treatment.

Ultrasmall Enzyodynamic PANoptosis Nano-Inducers for Ultrasound-Amplified Hepatocellular Carcinoma Therapy and Lung Metastasis Inhibition

Addressing the inefficiency of current therapeutic approaches for hepatocellular carcinoma is an urgent and pressing challenge. PANoptosis, a form of inflammatory programmed cell death, presents a dependable strategy for combating cancer by engaging multiple cell death pathways (apoptosis, pyroptosis, and necroptosis). In this study, an ultrasmall Bi2Sn2O7 nanozyme with ultrasound-magnified multienzyme-mimicking properties is designed and engineered as a PANoptosis inducer through destroying the mitochondrial function of tumor cells and enhancing the intracellular accumulation of toxic reactive oxygen species, finally triggering the activation of PANoptosis process. The role of PANoptosis inducer has been verified by the expression of related proteins, including cleaved Caspase 3, NLRP3, N-GSDMD, cleaved Caspase 1, p-MLKL, and RIPK3. The inclusion of external ultrasonic irradiation significantly augments the enzyodynamic therapeutic efficiency. In vitro and in vivo antineoplastic efficacy, along with inhibition of lung metastasis, validate the benefits of the Bi2Sn2O7-mediated PANoptosis pathway. This study not only elucidates the intricate mechanisms underlying Bi2Sn2O7 as a PANoptosis inducer, but also offers a novel perspective for the treatment of hepatocellular carcinoma.

Lycium barbarum polysaccharides (LBP) suppresses hypoxia/reoxygenation (H/R)-induced rat H9C2 cardiomyocytes pyroptosis via Nrf2/HO-1 signaling pathway

This study aimed to explore the mechanism that Lycium barbarum polysaccharides (LBP) suppress hypoxia/reoxygenation (H/R)-caused pyroptosis in cardiomyocytes (H9C2) via the Nrf2/HO-1 pathway. Initially, we established the cell model of H/R (6 h hypoxia plus with 24 h reoxygenation), and found that 90 μg/mL LBP was the optimal concentration. Subsequently, we confirmed that LBP reduced the apoptosis rate of cells after H/R, the activity of LDH, the inflammatory factors IL-1β and IL-18, and the levels of pyroptosis-specific markers ASC, NLRP3, and Caspase-1 (mRNAs and proteins). It increased the cell survival rate and the mRNA levels of the Nrf2/HO-1 pathway markers Nrf2 and HO-1, and allowed cytoplasmic Nrf2 protein to enter the nucleus to activate HO-1 protein. The Nrf2 siRNA2 caused the following events in H/R model: (1) the increases of the apoptosis rate, LDH activity, the levels of inflammatory factors (IL-1β and IL-18), the levels of ACS, NLRP3, and Caspase-1 (mRNAs and proteins); and (2) the decreases of the cell survival rate, the mRNA levels of Nrf2 and HO-1, and the protein levels of cytoplasm-Nrf2, nucleus-Nrf2, and HO-1. Therefore we concluded that 90 μg/mL LBP suppressed H/R-induced H9C2 cardiomyocyte pyroptosis via the Nrf2/HO-1 pathway.

The mode of action of sorafenib in MDA-MB-231 breast carcinoma cells involves components of apoptotic, necroptotic and autophagy-dependent cell death pathways

We report the identification of an interesting mode of action by sorafenib (SF) (Nexavar) in triple-negative breast adenocarcinoma MDA-MB-231 cells. The dying cells presented features of apoptosis, such as externalization of phosphatidylserine and cleaved caspase-3, and autophagy-mediated cell death, such as formation of autophagosomes and autolysosomes, the overexpression of LC3-II, and the presence of LAMP1-positive vacuoles, while displaying insufficient autophagic flux. Components of endoplasmic reticulum stress (ER stress; PERK and CHOP) and of necroptosis (p-MLKL) were also elevated considerably. Investigating potential target proteins that could modulate this form of cell death, we next investigated the role of tubulin disruption, which is known to induce necroptosis, apoptosis, and autophagy-dependent cell death. Interactions of SF with purified tubulin were investigated in detail using a combination of cellular and biophysical assays, transmission electron microscopy, and computer simulations. A marked reduction in the intrinsic tryptophan fluorescence of tubulin, a concentration-dependent elevation of anilinonaphthalene sulfonate-tubulin complex fluorescence, electron micrographs of deformed in vitro-assembled microtubules, and disrupted and hyper-stabilized cellular microtubules evinced the ability of SF to target tubulin and disrupt cellular microtubules. Molecular docking and molecular dynamic simulations positioned the drug between the α and β subunits of tubulin with considerable stability (ΔGbind, -31.43 kcal/mol), suggesting that drug-induced perturbation of tubulin could contribute to this mode of cell death.

Characterization of PANoptosis-related genes with immunoregulatory features in osteoarthritis

This study aimed to characterize PANoptosis-related genes with immunoregulatory features in osteoarthritis (OA) and investigate their potential diagnostic and therapeutic implications. Gene expression data from OA patients and healthy controls were obtained from the Gene Expression Omnibus (GEO) database. Differential expression analysis and functional enrichment analysis were conducted to identify PANoptosis-related genes (PRGs) associated with OA pathogenesis. A diagnostic model was developed using LASSO regression, and the diagnostic value of key PRGs was evaluated using Receiver Operating Characteristic Curve (ROC) analysis. The infiltration of immune cells and potential small molecule agents were also examined. A total of 39 differentially expressed PANoptosis-related genes (DE-PRGs) were identified, with functional enrichment analysis revealing their involvement in inflammatory response regulation and immune modulation pathways. Seven key PRGs, including CDKN1A, EZH2, MEG3, NR4A1, PIK3R2, S100A8, and SYVN1, were selected for diagnostic model construction, demonstrating high predictive performance in both training and validation datasets. The correlation between key PRGs and immune cell infiltration was explored. Additionally, molecular docking analysis identified APHA-compound-8 as a potential therapeutic agent targeting key PRGs. This study identified and analyzed PRGs in OA, uncovering their roles in immune regulation. Seven key PRGs were used to construct a diagnostic model with high predictive performance. The identified PRGs' correlation with immune cell infiltration was elucidated, and APHA-compound-8 was highlighted as a potential therapeutic agent. These findings offer novel diagnostic markers and therapeutic targets for OA, warranting further in vivo validation and exploration of clinical applications.

Caspase-8 in inflammatory diseases: a potential therapeutic target

Caspase-8, a renowned cysteine-aspartic protease within its enzyme family, initially garnered attention for its regulatory role in extrinsic apoptosis. With advancing research, a growing body of evidence has substantiated its involvement in other cell death processes, such as pyroptosis and necroptosis, as well as its modulatory effects on inflammasomes and proinflammatory cytokines. PANoptosis, an emerging concept of cell death, encompasses pyroptosis, apoptosis, and necroptosis, providing insight into the often overlapping cellular mortality observed during disease progression. The activation or deficiency of caspase-8 enzymatic activity is closely linked to PANoptosis, positioning caspase-8 as a key regulator of cell survival or death across various physiological and pathological processes. Aberrant expression of caspase-8 is closely associated with the development and progression of a range of inflammatory diseases, including immune system disorders, neurodegenerative diseases (NDDs), sepsis, and cancer. This paper delves into the regulatory role and impact of caspase-8 in these conditions, aiming to elucidate potential therapeutic strategies for the future intervention.

E3 Ubiquitin Ligase Smurf1 Regulates the Inflammatory Response in Macrophages and Attenuates Hepatic Damage during Betacoronavirus Infection

The E3 ubiquitin ligase Smurf1 catalyzes the ubiquitination and proteasomal degradation of several protein substrates related to inflammatory responses and antiviral signaling. This study investigated the role of Smurf1 in modulating inflammation induced by Betacoronavirus infection. Bone marrow-derived macrophages (BMDMs) from C57BL/6 (wild-type) or Smurf1-deficient (Smurf1-/-) mice were infected with MHV-A59 to evaluate the inflammatory response in vitro. Smurf1 was found to be required to downregulate the macrophage production of pro-inflammatory mediators, including TNF, and CXCL1; to control viral release from infected cells; and to increase cell viability. To assess the impact of Smurf 1 in vivo, we evaluated the infection of mice with MHV-A59 through the intranasal route. Smurf1-/- mice infected with a lethal inoculum of MHV-A59 succumbed earlier to infection. Intranasal inoculation with a 10-fold lower dose of MHV-A59 resulted in hematological parameter alterations in Smurf1-/- mice suggestive of exacerbated systemic inflammation. In the lung parenchyma, Smurf1 expression was essential to promote viral clearance, downregulating IFN-β mRNA and controlling the inflammatory profile of macrophages and neutrophils. Conversely, Smurf1 did not affect IFN-β mRNA regulation in the liver, but it was required to increase TNF and iNOS expression in neutrophils and decrease TNF expression in macrophages. In addition, Smurf1-/- mice exhibited augmented liver injuries, accompanied by high serum levels of alanine aminotransferase (ALT). These findings suggest that Smurf1 plays a critical role in regulating the inflammatory response in macrophages and attenuating systemic inflammation during Betacoronavirus infection.

Generation of Anti-Mastitis Gene-Edited Dairy Goats with Enhancing Lysozyme Expression by Inflammatory Regulatory Sequence using ISDra2-TnpB System

Gene-editing technology has become a transformative tool for the precise manipulation of biological genomes and holds great significance in the field of animal disease-resistant breeding. Mastitis, a prevalent disease in animal husbandry, imposes a substantial economic burden on the global dairy industry. In this study, a regulatory sequence gene editing breeding strategy for the successful creation of a gene-edited dairy (GED) goats with enhanced mastitis resistance using the ISDra2-TnpB system and dairy goats as the model animal is proposed. This included the targeted integration of an innate inflammatory regulatory sequence (IRS) into the promoter region of the lysozyme (LYZ) gene. Upon Escherichia Coli (E. coli) mammary gland infection, GED goats exhibited increased LYZ expression, showing robust anti-mastitis capabilities, mitigating PANoptosis activation, and alleviating blood-milk-barrier (BMB) damage. Notably, LYZ is highly expressed only in E. coli infection. This study marks the advent of anti-mastitis gene-edited animals with exogenous-free gene expression and demonstrates the feasibility of the gene-editing strategy proposed in this study. In addition, it provides a novel gene-editing blueprint for developing disease-resistant strains, focusing on disease specificity and biosafety while providing a research basis for the widespread application of the ISDra2-TnpB system.

Aphthous stomatitis - computational biology suggests external biotic stimulus and immunogenic cell death involved

BACKGROUND

The exact cause of recurrent aphthous stomatitis is still unknown, making it a challenge to develop effective treatments. This study employs computational biology to investigate the molecular basis of recurrent aphthous stomatitis, aiming to identify the nature of the stimuli triggering these ulcers and the type of cell death involved.

METHODS

To understand the molecular underpinnings of recurrent aphthous stomatitis, we used the Génie tool for gene identification, targeting those associated with cell death in recurrent aphthous stomatitis. The ToppGene Suite was employed for functional enrichment analysis. We also used Reactome and InteractiVenn for protein integration and prioritization against a PANoptosis gene list, enabling the construction of a protein-protein interaction network to pinpoint key proteins in recurrent aphthous stomatitis pathogenesis.

RESULTS

The study's computational approach identified 1,375 protein-coding genes linked to recurrent aphthous stomatitis. Critical among these were proteins responsive to bacterial stimuli, especially high mobility group protein B1 (HMGB1), toll-like receptor 2 (TLR2), and toll-like receptor 4 (TLR4). The enrichment analysis suggested an external biotic factor, likely bacterial, as a triggering agent in recurrent aphthous stomatitis. The protein interaction network highlighted the roles of tumor necrosis factor (TNF), NF-kappa-B essential modulator (IKBKG), and tumor necrosis factor receptor superfamily member 1A (TNFRSF1A), indicating an immunogenic cell death mechanism, potentially PANoptosis, in recurrent aphthous stomatitis.

CONCLUSION

The findings propose that bacterial stimuli could trigger recurrent aphthous stomatitis through a PANoptosis-related cell death pathway. This new understanding of recurrent aphthous stomatitis pathogenesis underscores the significance of oral microbiota in the condition. Future experimental validation and therapeutic strategy development based on these findings are necessary.

Identification of a novel PANoptosis-related gene signature for predicting the prognosis in clear cell renal cell carcinoma

PANoptosis has been shown to play an important role in tumorigenesis and gain more attention. Yet, the prognostic significance of PANoptosis-related genes has not been investigated more in clear cell renal cell carcinoma (ccRCC). The aim of this research was designed to identify and create a signature of PANoptosis-related genes which was expected to predict prognosis of ccRCC more effectively. The transcriptome data and clinical information were collected from The Cancer Genome Atlas database and the Gene Expression Omnibus database. Optimal differentially expressed PANoptosis-related genes, which were closely associated with prognosis and employed to construct a risk score, were extracted by univariate Cox analysis, least absolute shrinkage and selection operator Cox regression and multivariate Cox analysis. We performed Kaplan-Meier survival analysis and time-dependent receiver operating characteristic curves to complete this process. By adopting univariate and multivariate analysis, the constructed risk score was assessed to verify whether it could be taken as an independent contributor for prognosis. Moreover, we created a nomogram in order to predict overall survival (OS) of ccRCC. Five differentially expressed PANoptosis-related genes were screened out and used to construct a risk score. Our results showed that ccRCC patients with high risk score had a poor prognosis and shorter OS. The results of Kaplan-Meier curves and the area under the receiver operating characteristic curves of 1-, 3-, and 5-year OS indicated that the prediction performance was satisfactory. Additionally, the risk model could be taken as an independent prognostic factor in training and validation cohorts. The nomogram exhibited excellent reliability in predicting OS, which was validated by calibration curves. We identified 5 PANoptosis-related genes, which were used to construct a risk score and a nomogram for prognostic prediction with reliable predictive capability. The present study may provide new potential therapeutic targets and precise treatment strategies for ccRCC.

Ginkgo Flavone Aglycone Ameliorates Atherosclerosis via Inhibiting Endothelial Pyroptosis by Activating the Nrf2 Pathway

Natural antioxidants have been shown to be effective against atherosclerosis. Ginkgo flavone aglycone (GA) has strong antioxidant properties and can protect against endothelial damage. However, the mechanisms by which GA protects against atherosclerosis remain largely unexplored. This study hopes to find the anti-atherosclerotic mechanism of GA. ApoE-/- mice fed a high-fat diet were used for modeling atherosclerosis. The efficacy of GA on mice with atherosclerosis was evaluated based on the following indicators: Oil Red O staining, Masson staining, lipid content, and apoptosis. Transmission electron microscopy, Western blot, immunofluorescence staining, and propidium iodide staining were used to analyze the effects of GA on ox-LDL-treated human aortic endothelial cells. GA activated Nrf2 by promoting the nuclear translocation of Nrf2, thereby inhibiting endothelial pyroptosis. GA prevented endothelial pyroptosis suppressed oxidative stress, and inhibited the development of atherosclerosis in ApoE-/- mice fed high-fat diets. At the cellular level, GA suppressed ox-LDL-induced pyroptosis of HAECs by reducing reactive oxygen species (ROS) levels and inhibiting NLRP3 inflammasome. Furthermore, siRNA targeting Nrf2 or ML385, an Nrf2 inhibitor, reversed these effects. GA liberated Nrf2 from Keap1 sequestration, enhanced the nuclear translocation of Nrf2 and the transcription of downstream antioxidant proteins, reinforced the antioxidant defense system, and inhibited oxidative stress, thereby preventing endothelial cell pyroptosis, and attenuating the progression of atherosclerosis. This study indicated that GA mitigated endothelial pyroptosis by modulating Keap1/Nrf2 interactions, shedding light on the potential mechanisms underlying the protective effects of natural antioxidants against atherosclerosis.

PANoptosis and cardiovascular disease: The preventive role of exercise training

Regulated cell death, including pyroptosis, apoptosis, and necroptosis, is vital for the body's defense system. Recent research suggests that these three types of cell death are interconnected, giving rise to a new concept called PANoptosis. PANoptosis has been linked to various diseases, making it crucial to comprehend its mechanism for effective treatments. PANoptosis is controlled by upstream receptors and molecular signals, which form polymeric complexes known as PANoptosomes. Cell death combines necroptosis, apoptosis, and pyroptosis and cannot be fully explained by any of these processes alone. Understanding pyroptosis, apoptosis, and necroptosis is essential for understanding PANoptosis. Physical exercise has been shown to suppress pyroptotic, apoptotic, and necroptotic signaling pathways by reducing inflammatory factors, proapoptotic factors, and necroptotic factors such as caspases and TNF-alpha. This ultimately leads to a decrease in cardiac structural remodeling. The beneficial effects of exercise on cardiovascular health may be attributed to its ability to inhibit these cell death pathways.

PANoptosis: a new insight for oral diseases

PANoptosis, a burgeoning area of research, is a unique type of programmed cell death typified by pyroptosis, apoptosis, and necroptosis, yet it defies singular classification by any one mode of death. The assembly and activation of PANoptosomes are pivotal processes in PANoptosis, with several PANoptosomes already identified. Linkages between PANoptosis and the pathophysiology of various systemic illnesses are established, with increasing recognition of its association with oral ailments. This paper aims to deepen understanding by conducting a comprehensive analysis of the molecular pathways driving PANoptosis and exploring its potential implications in oral diseases.

Biological function and potential application of PANoptosis-related genes in colorectal carcinogenesis

PANoptosis induces programmed cell death (PCD) through extensive crosstalk and is associated with development of cancer. However, the functional mechanisms, clinical significance, and potential applications of PANoptosis-related genes (PRGs) in colorectal cancer (CRC) have not been fully elucidated. Functional enrichment of key PRGs was analyzed based on databases, and relationships between key PRGs and the immune microenvironment, immune cell infiltration, chemotherapy drug sensitivity, tumor progression genes, single-cell cellular subgroups, signal transduction pathways, transcription factor regulation, and miRNA regulatory networks were systematically explored. This study identified 5 key PRGs associated with CRC: BCL10, CDKN2A, DAPK1, PYGM and TIMP1. Then, RT-PCR was used to verify expression of these genes in CRC cells and tissues. Clinical significance and prognostic value of key genes were further verified by multiple datasets. Analyses of the immune microenvironment, immune cell infiltration, chemotherapy drug sensitivity, tumor progression genes, single-cell cellular subgroups, and signal transduction pathways suggest a close relationship between these key genes and development of CRC. In addition, a novel prognostic nomogram model for CRC was successfully constructed by combining important clinical indicators and the key genes. In conclusion, our findings offer new insights for understanding the pathogenesis of CRC, predicting CRC prognosis, and identifying multiple therapeutic targets for future CRC therapy.

PANoptosis: Novel insight into regulated cell death and its potential role in cardiovascular diseases (Review)

PANoptosis, a complex form of proinflammatory programmed cell death, including apoptosis, pyroptosis and necroptosis, has been an emerging concept in recent years that has been widely reported in cancer, infectious diseases and neurological disorders. Cardiovascular diseases (CVDs) are an important global health problem, posing a serious threat to individuals' lives. An increasing body of research shows that inflammation has a pivotal role in CVDs, which provides an important theoretical basis for PANoptosis to promote the progression of CVDs. To date, only sporadic studies on PANoptosis in CVDs have been reported and its role in the field of CVDs has not been fully explored. Elucidating the various modes of cardiomyocyte death, the specific molecular mechanisms and the links among the various modes of death under various stressful stimuli is of notable clinical significance for a deeper understanding of the pathophysiology of CVDs. The present review summarizes the molecular mechanisms of apoptosis, pyroptosis, necroptosis and PANoptosis and their prospects in the field of CVDs.

Exploration of the mode of death and potential death mechanisms of nucleus pulposus cells

Intervertebral disc degeneration (IVDD) is a common chronic orthopaedic disease in orthopaedics that imposes a heavy economic burden on people and society. Although it is well established that IVDD is associated with genetic susceptibility, ageing and obesity, its pathogenesis remains incompletely understood. Previously, IVDD was thought to occur because of excessive mechanical loading leading to destruction of nucleus pulposus cells (NPCs), but studies have shown that IVDD is a much more complex process associated with inflammation, metabolic factors and NPCs death and can involve all parts of the disc, characterized by causing NPCs death and extracellular matrix (ECM) degradation. The damage pattern of NPCs in IVDD is like that of some programmed cell death, suggesting that IVDD is associated with programmed cell death. Although apoptosis and pyroptosis of NPCs have been studied in IVDD, the pathogenesis of intervertebral disc degeneration can still not be fully elucidated by using only traditional cell death modalities. With increasing research, some new modes of cell death, PANoptosis, ferroptosis and senescence have been found to be closely related to intervertebral disc degeneration. Among these, PANoptosis combines essential elements of pyroptosis, apoptosis and necroptosis to form a highly coordinated and dynamically balanced programmed inflammatory cell death process. Furthermore, we believe that PANoptosis may also crosstalk with pyroptosis and senescence. Therefore, we review the progress of research on multiple deaths of NPCs in IVDD to provide guidance for clinical treatment.

The ROS Mediates MCUb in Mitochondria-Regulated Apoptosis of TM4 Cells Induced by Titanium Dioxide Nanoparticles

Titanium dioxide nanoparticles (TiO2 NPs) can cause mitochondrial apoptosis of TM4 cells associated with reactive oxygen species (ROS) accumulation and Ca2+ overload, but the relations among these processes remain unclear. This study aimed to evaluate whether the accumulation of ROS caused by TiO2 NPs inhibits MCUb expression, leading to mitochondrial calcium overload and subsequent cell apoptosis through the mitochondrial pathway. TM4 cells were exposed to different concentrations of TiO2 NPs (0, 25, 50, 75, 100 μg/mL) for 24 h. We assessed cell viability, ROS level, MCUb and VDAC1 expression, mitochondrial and cytoplasmic Ca2+ levels, mitochondrial membrane potential (MMP), apoptosis rate, and key proteins related to mitochondrial apoptosis (Bcl-2, Bax, Caspase 3, Caspase 9, p53 and Cyt c). Additionally, the effect of N-acetylcysteine (NAC) on MCUb expression, calcium homeostasis, and cell apoptosis was evaluated. Compared to control group, TiO2 NPs significantly increased ROS level, downregulated MCUb expression, elevated Ca2+ levels in mitochondria and cytoplasm, and enhanced mitochondria-regulated apoptosis, starting from the 50 μg/mL TiO2 NPs group. However, NAC significantly increased MCUb expression, attenuated Ca2+ levels in mitochondria and cytoplasm, and reduced mitochondria-related apoptosis. In conclusion, TiO2 NPs induced ROS accumulation, which inhibited the expression of MCUb. The decreased MCUb level led to Ca2+ overload in mitochondria, causing TM4 cell apoptosis via the mitochondrial pathway. This research elucidates, for the first time, the role of MCUb and its relation with ROS in apoptosis of TM4 cells induced by TiO2 NPs, which supplementing the molecular mechanism of cell apoptosis caused by TiO2 NPs.

Diabetic peripheral neuropathy based on Schwann cell injury: mechanisms of cell death regulation and therapeutic perspectives

Diabetic peripheral neuropathy (DPN) is a complication of diabetes mellitus that lacks specific treatment, its high prevalence and disabling neuropathic pain greatly affects patients' physical and mental health. Schwann cells (SCs) are the major glial cells of the peripheral nervous system, which play an important role in various inflammatory and metabolic neuropathies by providing nutritional support, wrapping axons and promoting repair and regeneration. Increasingly, high glucose (HG) has been found to promote the progression of DPN pathogenesis by targeting SCs death regulation, thus revealing the specific molecular process of programmed cell death (PCD) in which SCs are disrupted is an important link to gain insight into the pathogenesis of DPN. This paper is the first to review the recent progress of HG studies on apoptosis, autophagy, pyroptosis, ferroptosis and necroptosis pathways in SCs, and points out the crosstalk between various PCDs and the related therapeutic perspectives, with the aim of providing new perspectives for a deeper understanding of the mechanisms of DPN and the exploration of effective therapeutic targets.

Gas6-Axl signal promotes indoor VOCs exposure-induced pulmonary fibrosis via pulmonary microvascular endothelial cells-fibroblasts cross-talk

Volatile organic compounds (VOCs) as environmental pollutants were associated with respiratory diseases. Pulmonary fibrosis (PF) was characterized by an increase of extracellular matrix, leading to deterioration of lung function. The adverse effects on lung and the potential mechanism underlying VOCs induced PF had not been elucidated clearly. In this study, the indoor VOCs exposure mouse model along with an ex vivo biosensor assay was established. Based on scRNA-seq analysis, the adverse effects on lung and potential molecular mechanism were studied. Herein, the results showed that VOCs exposure from indoor decoration contributed to decreased lung function and facilitated pulmonary fibrosis in mice. Then, the whole lung cell atlas after VOCs exposure and the heterogeneity of fibroblasts were revealed. We explored the molecular interactions among various pulmonary cells, suggesting that endothelial cells contributed to fibroblasts activation in response to VOCs exposure. Mechanistically, pulmonary microvascular endothelial cells (MPVECs) secreted Gas6 after VOCs-induced PANoptosis phenotype, bound to the Axl in fibroblasts, and then activated fibroblasts. Moreover, Atf3 as the key gene negatively regulated PANoptosis phenotype to ameliorate fibrosis induced by VOCs exposure. These novel findings provided a new perspective about MPVECs could serve as the initiating factor of PF induced by VOCs exposure.

A2 reactive astrocyte-derived exosomes alleviate cerebral ischemia-reperfusion injury by delivering miR-628

Ischemia and hypoxia activate astrocytes into reactive types A1 and A2, which play roles in damage and protection, respectively. However, the function and mechanism of A1 and A2 astrocyte exosomes are unknown. After astrocyte exosomes were injected into the lateral ventricle, infarct volume, damage to the blood-brain barrier (BBB), apoptosis and the expression of microglia-related proteins were measured. The dual luciferase reporter assay was used to detect the target genes of miR-628, and overexpressing A2-Exos overexpressed and knocked down miR-628 were constructed. qRT-PCR, western blotting and immunofluorescence staining were subsequently performed. A2-Exos obviously reduced the infarct volume, damage to the BBB and apoptosis and promoted M2 microglial polarization. RT-PCR showed that miR-628 was highly expressed in A2-Exos. Dual luciferase reporter assays revealed that NLRP3, S1PR3 and IRF5 are target genes of miR-628. After miR-628 was overexpressed or knocked down, the protective effects of A2-Exos increased or decreased, respectively. A2-Exos reduced pyroptosis and BBB damage and promoted M2 microglial polarization through the inhibition of NLRP3, S1PR3 and IRF5 via the delivery of miR-628. This study explored the mechanism of action of A2-Exos and provided new therapeutic targets and concepts for treating cerebral ischemia.

In Vivo Approaches to Understand Arrhythmogenic Cardiomyopathy: Perspectives on Animal Models

Arrhythmogenic cardiomyopathy (AC) is a hereditary cardiac disorder characterized by the gradual replacement of cardiomyocytes with fibrous and adipose tissue, leading to ventricular wall thinning, chamber dilation, arrhythmias, and sudden cardiac death. Despite advances in treatment, disease management remains challenging. Animal models, particularly mice and zebrafish, have become invaluable tools for understanding AC's pathophysiology and testing potential therapies. Mice models, although useful for scientific research, cannot fully replicate the complexity of the human AC. However, they have provided valuable insights into gene involvement, signalling pathways, and disease progression. Zebrafish offer a promising alternative to mammalian models, despite the phylogenetic distance, due to their economic and genetic advantages. By combining animal models with in vitro studies, researchers can comprehensively understand AC, paving the way for more effective treatments and interventions for patients and improving their quality of life and prognosis.

Atramacronoid A induces the PANoptosis-like cell death of human breast cancer cells through the CASP-3/PARP-GSDMD-MLKL pathways

Breast cancer is the most common malignant tumor and a major cause of mortality among women worldwide. Atramacronoid A (AM-A) is a unique natural sesquiterpene lactone isolated from the rhizome of Atractylodes macrocephala Koidz (known as Baizhu in Chinese). Our study demonstrated that AM-A triggers a specific form of cell death resembling PANoptosis-like cell death. Further analysis indicated that AM-A-induced PANoptosis-like cell death is associated with the CASP-3/PARP-GSDMD-MLKL pathways, which are mediated by mitochondrial dysfunction. These results suggest the potential of AM-A as a lead compound and offer insights for the development of therapeutic agents for breast cancer from natural products.

The necroptosis cell death pathway drives neurodegeneration in Alzheimer's disease

Although apoptosis, pyroptosis, and ferroptosis have been implicated in AD, none fully explains the extensive neuronal loss observed in AD brains. Recent evidence shows that necroptosis is abundant in AD, that necroptosis is closely linked to the appearance of Tau pathology, and that necroptosis markers accumulate in granulovacuolar neurodegeneration vesicles (GVD). We review here the neuron-specific activation of the granulovacuolar mediated neuronal-necroptosis pathway, the potential AD-relevant triggers upstream of this pathway, and the interaction of the necrosome with the endo-lysosomal pathway, possibly providing links to Tau pathology. In addition, we underscore the therapeutic potential of inhibiting necroptosis in neurodegenerative diseases such as AD, as this presents a novel avenue for drug development targeting neuronal loss to preserve cognitive abilities. Such an approach seems particularly relevant when combined with amyloid-lowering drugs.

Titanium dioxide nanoparticles induce apoptosis through ROS-Ca2+-p38/AKT/mTOR pathway in TM4 cells

Titanium dioxide nanoparticles (TiO2 NPs) can cause apoptosis in TM4 cells; however, the underlying mechanism has not been entirely elucidated. The purpose of this study was to investigate the effects of TiO2 NPs on ROS, Ca2+ level, p38/AKT/mTOR pathway, and apoptosis in TM4 cells and to evaluate the role of Ca2+ in p38/AKT/mTOR pathway and apoptosis. After exposure to different concentrations (0, 50, 100, 150, and 200 μg/mL) of TiO2 NPs for 24 h, cell viability, ROS, Ca2+ level, Ca2+-ATPase activity, p38/AKT/mTOR pathway-related proteins, apoptosis rate, and apoptosis-related proteins (Bax, Bcl-2, Caspase 3, Caspase 9, and p53) were detected. The ROS scavenger NAC was used to determine the effect of ROS on Ca2+ level. The Ca2+ chelator BAPTA-AM was used to evaluate the role of Ca2+ in p38/AKT/mTOR pathway and apoptosis. TiO2 NPs significantly inhibited cell viability, increased ROS level, and elevated Ca2+ level while suppressing Ca2+-ATPase activity. TiO2 NPs regulated the p38/AKT/mTOR pathway via increasing p-p38 level and decreasing p-AKT and p-mTOR levels. TiO2 NPs significantly enhanced the apoptosis. NAC attenuated Ca2+ overload and reduction in Ca2+-ATPase activity caused by TiO2 NPs. BAPTA-AM alleviated TiO2 NPs-induced abnormal expression of p38/AKT/mTOR pathway-related proteins. BAPTA-AM assuaged the apoptosis caused by TiO2 NPs. Altogether, this study revealed that TiO2 NPs elevated intracellular Ca2+ level through ROS accumulation. Subsequently, the heightened intracellular Ca2+ level was observed to exert regulation over the p38/AKT/mTOR pathway, ultimately culminating in apoptosis. These results provides a complementary understanding to the mechanism of TiO2 NPs-induced apoptosis in TM4 cells.

Neurotoxic β-amyloid oligomers cause mitochondrial dysfunction-the trigger for PANoptosis in neurons

As the global population ages, the incidence of elderly patients with dementia, represented by Alzheimer's disease (AD), will continue to increase. Previous studies have suggested that β-amyloid protein (Aβ) deposition is a key factor leading to AD. However, the clinical efficacy of treating AD with anti-Aβ protein antibodies is not satisfactory, suggesting that Aβ amyloidosis may be a pathological change rather than a key factor leading to AD. Identification of the causes of AD and development of corresponding prevention and treatment strategies is an important goal of current research. Following the discovery of soluble oligomeric forms of Aβ (AβO) in 1998, scientists began to focus on the neurotoxicity of AβOs. As an endogenous neurotoxin, the active growth of AβOs can lead to neuronal death, which is believed to occur before plaque formation, suggesting that AβOs are the key factors leading to AD. PANoptosis, a newly proposed concept of cell death that includes known modes of pyroptosis, apoptosis, and necroptosis, is a form of cell death regulated by the PANoptosome complex. Neuronal survival depends on proper mitochondrial function. Under conditions of AβO interference, mitochondrial dysfunction occurs, releasing lethal contents as potential upstream effectors of the PANoptosome. Considering the critical role of neurons in cognitive function and the development of AD as well as the regulatory role of mitochondrial function in neuronal survival, investigation of the potential mechanisms leading to neuronal PANoptosis is crucial. This review describes the disruption of neuronal mitochondrial function by AβOs and elucidates how AβOs may activate neuronal PANoptosis by causing mitochondrial dysfunction during the development of AD, providing guidance for the development of targeted neuronal treatment strategies.

Identification of PANoptosis-related subtypes, construction of a prognosis signature, and tumor microenvironment landscape of hepatocellular carcinoma using bioinformatic analysis and experimental verification

Background

Hepatocellular carcinoma (HCC) is one of the most lethal malignancies worldwide. PANoptosis is a recently unveiled programmed cell death pathway, Nonetheless, the precise implications of PANoptosis within the context of HCC remain incompletely elucidated.

Methods

We conducted a comprehensive bioinformatics analysis to evaluate both the expression and mutation patterns of PANoptosis-related genes (PRGs). We categorized HCC into two clusters and identified differentially expressed PANoptosis-related genes (DEPRGs). Next, a PANoptosis risk model was constructed using LASSO and multivariate Cox regression analyses. The relationship between PRGs, risk genes, the risk model, and the immune microenvironment was studies. In addition, drug sensitivity between high- and low-risk groups was examined. The expression profiles of these four risk genes were elucidate by qRT-PCR or immunohistochemical (IHC). Furthermore, the effect of CTSC knock down on HCC cell behavior was verified using in vitro experiments.

Results

We constructed a prognostic signature of four DEPRGs (CTSC, CDCA8, G6PD, and CXCL9). Receiver operating characteristic curve analyses underscored the superior prognostic capacity of this signature in assessing the outcomes of HCC patients. Subsequently, patients were stratified based on their risk scores, which revealed that the low-risk group had better prognosis than those in the high-risk group. High-risk group displayed a lower Stromal Score, Immune Score, ESTIMATE score, and higher cancer stem cell content, tumor mutation burden (TMB) values. Furthermore, a correlation was noted between the risk model and the sensitivity to 56 chemotherapeutic agents, as well as immunotherapy efficacy, in patient with. These findings provide valuable guidance for personalized clinical treatment strategies. The qRT-PCR analysis revealed that upregulated expression of CTSC, CDCA8, and G6PD, whereas downregulated expression of CXCL9 in HCC compared with adjacent tumor tissue and normal liver cell lines. The knockdown of CTSC significantly reduced both HCC cell proliferation and migration.

Conclusion

Our study underscores the promise of PANoptosis-based molecular clustering and prognostic signatures in predicting patient survival and discerning the intricacies of the tumor microenvironment within the context of HCC. These insights hold the potential to advance our comprehension of the therapeutic contribution of PANoptosis plays in HCC and pave the way for generating more efficacious treatment strategies.

PLA inhibits TNF-α-induced PANoptosis of prostate cancer cells through metabolic reprogramming

Previous studies have shown that phenyllactic acid (alpha-Hydroxyhydrocinnamic acid, 2-Hydroxy-3-phenylpropionic acid, PLA), a type of organic acid metabolite, has excellent diagnostic efficacy when used to differentiate between prostate cancer, benign prostatic hyperplasia, and prostatitis. This research aims to explore the molecular mechanism by which PLA influences the PANoptosis of prostate cancer (PCa) cell lines. First, we found that PLA was detected in all prostate cancer cell lines (PC-3, PC-3 M, DU145, LNCAP). Further experiments showed that the addition of PLA to prostate cancer cells could promote ATP generation, enhance cysteine desulfurase (NFS1) expression, and reduce tumor necrosis factor alpha (TNF-α) levels, thereby inhibiting apoptosis in prostate cancer cells. Notably, overexpression of NFS1 can inhibit the binding of TNF-α to serpin mRNA binding protein 1 (SERBP1), suggesting that NFS1 competes with TNF-α for binding to SERBP1. Knockdown of SERBP1 significantly reduced the level of small ubiquity-related modifier (SUMO) modification of TNF-α. This suggests that NFS1 reduces the SUMO modification of TNF-α by competing with SERBP1, thereby reducing the expression and stability of TNF-α and ultimately inhibiting apoptosis in prostate cancer cell lines. In conclusion, PLA inhibits TNF-α induced panapoptosis of prostate cancer cells through metabolic reprogramming, providing a new idea for targeted treatment of prostate cancer.

Effect of lipopolysaccharide on TAK1-mediated hepatocyte PANoptosis through Toll-like receptor 4 during acute liver failure

BACKGROUND

Intestinal endotoxemia (IETM) is an important pathogenic mechanism of acute liver failure (ALF), and TAK1-mediated PANoptosis is a novel cell death mode. This study investigated whether IETM can induce hepatocyte PANoptosis during ALF.

METHOD

PANoptosis cell and mouse models were generated, and lentiviruses (LVs), adeno-associated viral vectors (AVVs), and small interfering RNAs (siRNAs) were subsequently used to overexpress or knock down TLR and TAK1. Then, the levels of hepatocyte injury, TLR4, TAK1 and PANoptosis were detected via an enzyme-labeling instrument, tissue staining, RT-PCR, western blotting, immunofluorescence, and flow cytometry.

RESULTS

The BioGRID database search revealed that TAK1 might interact with TLR4. According to the in vivo experiments, compared with those in ALF mice, liver tissue damage, hepatocyte mortality and PANoptosis in mice in the AAV-TAK1 group were significantly lower, and liver function was significantly improved. According to the in vitro experiments, after promoting the expression of TLR4 in the model group, the degree of cell damage, TLR4 expression and PANoptosis further increased, while the level of TAK1 further decreased. The opposite result was obtained when TLR4 expression was inhibited. The increase in TAK1 expression in the model group reduced the degree of cell damage and PANoptosis, but the level of TLR4 was not significantly changed. In the model group of cells that exhibited TAK1 expression, further promotion of TLR4 expression inhibited the protective effect of TAK1 on cells. In the model group of cells after TAK1 expression was promoted, if the expression of TLR4 was further promoted, the protective effect of TAK1 on cells was inhibited.

CONCLUSION

IETM inhibited the expression of TAK1 by binding to TLR4 molecules and promoting hepatocyte PANoptosis during ALF. Promoting TAK1 expression effectively relieved lipopolysaccharide-induced hepatocyte PANoptosis.

PANoptosis-related genes function as efficient prognostic biomarkers in colon adenocarcinoma

Background

PANoptosis is a newly discovered cell death type, and tightly associated with immune system activities. To date, the mechanism, regulation and application of PANoptosis in tumor is largely unknown. Our aim is to explore the prognostic value of PANoptosis-related genes in colon adenocarcinoma (COAD).

Methods

Analyzing data from The Cancer Genome Atlas-COAD (TCGA-COAD) involving 458 COAD cases, we concentrated on five PANoptosis pathways from the Molecular Signatures Database (MSigDB) and a comprehensive set of immune-related genes. Our approach involved identifying distinct genetic COAD subtype clusters and developing a prognostic model based on these parameters.

Results

The research successfully identified two genetic subtype clusters in COAD, marked by distinct profiles in PANoptosis pathways and immune-related gene expression. A prognostic model, incorporating these findings, demonstrated significant predictive power for survival outcomes, underscoring the interplay between PANoptosis and immune responses in COAD.

Conclusion

This study enhances our understanding of COAD's genetic framework, emphasizing the synergy between cell death pathways and the immune system. The development of a prognostic model based on these insights offers a promising tool for personalized treatment strategies. Future research should focus on validating and refining this model in clinical settings to optimize therapeutic interventions in COAD.

The mechanisms of ferroptosis and its role in atherosclerosis

Ferroptosis is a newly identified form of non-apoptotic programmed cell death, characterized by the iron-dependent accumulation of lethal lipid reactive oxygen species (ROS) and peroxidation of membrane polyunsaturated fatty acid phospholipids (PUFA-PLs). Ferroptosis is unique among other cell death modalities in many aspects. It is initiated by excessive oxidative damage due to iron overload and lipid peroxidation and compromised antioxidant defense systems, including the system Xc-/ glutathione (GSH)/glutathione peroxidase 4 (GPX4) pathway and the GPX4-independent pathways. In the past ten years, ferroptosis was reported to play a critical role in the pathogenesis of various cardiovascular diseases, e.g., atherosclerosis (AS), arrhythmia, heart failure, diabetic cardiomyopathy, and myocardial ischemia-reperfusion injury. Studies have identified dysfunctional iron metabolism and abnormal expression profiles of ferroptosis-related factors, including iron, GSH, GPX4, ferroportin (FPN), and SLC7A11 (xCT), as critical indicators for atherogenesis. Moreover, ferroptosis in plaque cells, i.e., vascular endothelial cell (VEC), macrophage, and vascular smooth muscle cell (VSMC), positively correlate with atherosclerotic plaque development. Many macromolecules, drugs, Chinese herbs, and food extracts can inhibit the atherogenic process by suppressing the ferroptosis of plaque cells. In contrast, some ferroptosis inducers have significant pro-atherogenic effects. However, the mechanisms through which ferroptosis affects the progression of AS still need to be well-known. This review summarizes the molecular mechanisms of ferroptosis and their emerging role in AS, aimed at providing novel, promising druggable targets for anti-AS therapy.

Exploration and breakthrough in the mode of chondrocyte death - A potential new mechanism for osteoarthritis

Osteoarthritis (OA) is a frequent chronic joint disease in orthopedics that effects individuals and society significantly. Obesity, aging, genetic susceptibility, and joint misalignment are all known risk factors for OA, but its pathomechanism is still poorly understood. Researches have revealed that OA is a much complex process related to inflammation, metabolic and chondrocyte death. It can affect all parts of the joint and is characterized by causing chondrocyte death and extracellular matrix descent. Previously, OA was thought to develop from excessive mechanical loading leading to the destruction of articular cartilage. Since some programmed cell deaths and OA share a pattern of chondrocyte destruction, it is likely that OA also involves programmed cell death. Even though chondrocyte apoptosis and pyroptosis have been investigated in OA, clarifing solely conventional cell death pathways is still insufficient to understand the pathophysiology of osteoarthritis. With more researches, it has been discovered that osteoarthritis and other new cell death processes, including PANoptosis, ferroptosis, and cell senescence, are strongly associated. Among these, PANoptosis combines the key traits of pyroptosis, cell apoptosis, and necrotic apoptosis into a highly coordinated and dynamically balanced programmed inflammatory cell death mechanism. Furthermore, we think that PANopotosis might obstruct necroptosis and cell senescence. Therefore, in order to offer direction for therapeutic treatment, we evaluate the development of research on multiple cell death of chondrocytes in OA.

Murine norovirus infection of macrophages induces intrinsic apoptosis as the major form of programmed cell death

Human norovirus is the leading cause of acute gastroenteritis worldwide, however despite the significance of this pathogen, we have a limited understanding of how noroviruses cause disease, and modulate the innate immune response. Programmed cell death (PCD) is an important part of the innate response to invading pathogens, but little is known about how specific PCD pathways contribute to norovirus replication. Here, we reveal that murine norovirus (MNV) virus-induced PCD in macrophages correlates with the release of infectious virus. We subsequently show, genetically and chemically, that MNV-induced cell death and viral replication occurs independent of the activity of inflammatory mediators. Further analysis revealed that MNV infection promotes the cleavage of apoptotic caspase-3 and PARP. Correspondingly, pan-caspase inhibition, or BAX and BAK deficiency, perturbed viral replication rates and delayed virus release and cell death. These results provide new insights into how MNV harnesses cell death to increase viral burden.

Innate immune responses to SARS-CoV-2

This chapter provides an overview of the innate immune response to SARS-CoV-2, focusing on the recognition, activation, and evasion strategies employed by the virus. The innate immune system plays a crucial role in the early defense against viral infections, and understanding its response to SARS-CoV-2 is essential for developing effective therapeutic approaches. The chapter begins by explaining the basics of the innate immune system, including its components and salient features. It discusses the various pattern recognition receptors involved in recognizing SARS-CoV-2, such as toll-like receptors, RIG-I-like receptors, NOD-like receptors, and other cytosolic sensors. The binding and entry of the virus into host cells and subsequent activation of innate immune cells, including neutrophils, monocytes, macrophages, dendritic cells, NK cells, and ILCs, are explored. Furthermore, the secretion of key cytokines and chemokines, including type I interferons, IL-6, IL-17, and TNF-alpha, is discussed as part of the innate immune response. The concept of PANoptosis, involving programmed cell death mechanisms, is introduced as a significant aspect of the response to SARS-CoV-2. The chapter also addresses the innate immune evasion strategies employed by SARS-CoV-2, which allow the virus to evade or subvert the host immune response, contributing to viral persistence. Understanding these strategies is crucial for developing targeted therapies against the virus.

Non-Canonical Inflammasome Pathway: The Role of Cell Death and Inflammation in Ehrlichiosis

Activating inflammatory caspases and releasing pro-inflammatory mediators are two essential functions of inflammasomes which are triggered in response to pathogen-associated molecular patterns (PAMPs) or danger-associated molecular patterns (DAMPs). The canonical inflammasome pathway involves the activation of inflammasome and its downstream pathway via the adaptor ASC protein, which causes caspase 1 activation and, eventually, the cleavage of pro-IL-1b and pro-IL-18. The non-canonical inflammasome pathway is induced upon detecting cytosolic lipopolysaccharide (LPS) by NLRP3 inflammasome in Gram-negative bacteria. The activation of NLRP3 triggers the cleavage of murine caspase 11 (human caspase 4 or caspase 5), which results in the formation of pores (via gasdermin) to cause pyroptosis. Ehrlichia is an obligately intracellular bacterium which is responsible for causing human monocytic ehrlichiosis (HME), a potentially lethal disease similar to toxic shock syndrome and septic shock syndrome. Several studies have indicated that canonical and non-canonical inflammasome activation is a crucial pathogenic mechanism that induces dysregulated inflammation and host cellular death in the pathophysiology of HME. Mechanistically, the activation of canonical and non-canonical inflammasome pathways affected by virulent Ehrlichia infection is due to a block in autophagy. This review aims to explore the significance of non-canonical inflammasomes in ehrlichiosis, and how the pathways involving caspases (with the exception of caspase 1) contribute to the pathophysiology of severe and fatal ehrlichiosis. Improving our understanding of the non-canonical inflammatory pathway that cause cell death and inflammation in ehrlichiosis will help the advancement of innovative therapeutic, preventative, and diagnostic approaches to the treatment of ehrlichiosis.