GSDME-mediated Pyroptosis Research Articles

Anagrelide and idarubicin combination induces GSDME-mediated pyroptosis as a potential therapy for high-PDE3A acute myeloid leukemia.

Acute myeloid leukemia (AML) is an invasive hematopoietic malignancy requiring novel treatment strategies. In this study, we identified phosphodiesterase 3 A (PDE3A) as a potential new target for drug repositioning in AML. PDE3A was preferentially overexpressed in AML cells than in normal cells, and high expression of PDE3A was correlated with lower event-free survival (EFS) in de novo AML patients. The PDE3A inhibitor anagrelide (ANA) profoundly suppresses the proliferation of high PDE3A-expressing AML cells while exhibiting minimal impact on those with low PDE3A expression. Moreover, synergistic effect of ANA with other chemotherapeutic drugs in high PDE3A expression AML cells was observed. The ANA-idarubicin (IDA) combination showed the most remarkable synergistic effect among all ANA-chemotherapeutic drugs commonly used in AML cell line models. Mechanistically, the synergy between ANA and IDA inhibited the survival of PDE3Ahigh AML cell lines through pyroptosis. This mechanism was initiated by GSDME cleavage triggered by caspase-3 activation. In vivo combination treatment of leukemic animals with high PDE3A expression significantly reduced leukemia burden and prolonged survival time compared with single-drug and vehicle control treatments. Our findings suggest that combined ANA and IDA treatment is an innovative and promising therapeutic strategy for AML patients with high PDE3A expression.

GSDME-mediated pyroptosis contributes to chemotherapy-induced platelet hyperactivity and thrombotic potential

AbstractThrombotic complications due to platelet hyperreactivity are a major cause of death in patients undergoing chemotherapy. However, the underlying mechanisms are not fully understood. Herein, using human platelets and platelets from mice lacking gasdermin E (GSDME), we showed that GSDME is functionally expressed in anucleate platelets, and that GSDME-mediated pyroptosis, a newly identified form of cell death in mammalian nucleated cells, contributes to platelet hyperactivity in cisplatin-based chemotherapy. Cisplatin or etoposide activates caspase-3 to cleave GSDME, thereby releasing the N-terminal fragment of GSDME (GSDME-N) toward the platelet plasma membrane, subsequently forming membrane pores and facilitating platelet granule release. This eventually promotes platelet hyperactivity and thrombotic potential. We identified flotillin-2, a scaffold protein, as a GSDME-N interactor that recruits GSDME-N to the platelet membrane. Loss of GSDME protects mice from cisplatin-induced platelet hyperactivity. Our results provide evidence that targeting GSDME-mediated pyroptosis could reduce thrombotic potential in chemotherapy.

Research progress on GSDME-mediated cell pyroptosis resulting in GSDME type hearing loss

Pyroptosis is a novel mode for programmed cell death discovered and confirmed in recent years. The Gasdermins (GSDMs) family is a key effector molecule mediating pyroptosis. As an important cause of extensive inflammatory damage and side effects of conventional chemotherapy drugs, anomalous pyroptosis has also been associated with hearing loss, tumor, and disorders of the immune system. The GSDME protein, encoded by the GSDME (DFNA5) gene, belongs to the GSDMs family and is a key factor mediating pyroptosis. Gain-of-function variants of the GSDME gene can lead to GSDME-related hearing loss, which shows an autosomal dominant inheritance. This article has reviewed the role of GSDME-mediated pyroptosis in the pathogenesis of GSDME-related hearing loss, with an aim to provide insights into the treatment of GSDME-related hearing loss.

Triclosan induces pyroptosis by activation of the caspase-9/3/gasdermin E axis

The high concentrations of TCS in personal care products, and the potential for even greater exposure in occupational settings, raise significant concerns about its cytotoxic effects. Numorous studies highlight the importance of understanding the molecular mechanisms of pyroptosis in toxicological research on environmental pollutants. However, it remains unclear whether TCS exposure could induce GSDME-mediated pyroptosis. In this study, we aimed to investigate the cytotoxic effects of 200 μM TCS on L02 cells and elucidate the molecular mechanisms involved in TCS-induced pyroptosis, a novel form of cell death. Our results demonstrate that TCS inhibits the proliferation of L02 cells in a dose-dependent manner and triggers caspase-dependent cell death, leading to mitochondrial dysfunction and subsequent pyroptosis through the activation of the caspase-9/3/GSDME axis. Furthermore, through transcriptional and metabolomic analyses, we identified alterations in the PI3K-Akt and MAPK cellular signaling pathways, as well as changes in carbon and nitrogen metabolism. Our data provide valuable insights into the biotoxicity of high TCS concentrations and establish a theoretical basis for future studies on its impact and risk.

A Membrane-Anchoring Self-Assembling Peptide Allows Bioorthogonal Coupling of Type-I AIEgens for Pyroptosis-Induced Cancer Therapy.

Enrichment of photosensitizers (PSs) on cancer cell membranes via bioorthogonal reactions is considered to be a very promising therapeutic modality. However, azide-modified sugars-based metabolic labeling processes usually lack targeting and the labeling speed is relatively slow. Moreover, it has been rarely reported that membrane-anchoring pure type-I PSs can induce cancer cell pyroptosis. Here, we report an alkaline phosphatase (ALP) and cholecystokinin-2 receptor (CCK2R) dual-targeting peptide named DBCO-pYCCK6, which can selectively and rapidly self-assemble on cancer cell membrane, and then bioorthogonal enrich type-I aggregation-induced emission luminogens (AIEgen) PSs (SAIE-N3) on the cell membrane. Upon light irradiation, the membrane-anchoring SAIE-N3 could effectively generate type-I reactive oxygen species (ROS) to induce gasdermin E (GSDME)-mediated pyroptosis. In vivo experiments demonstrated that the bioorthogonal combination strategy of peptide and AIEgen PSs could significantly inhibit tumor growth, which is accompanied by CD8+ cytotoxic T cell infiltration. This work provides a novel self-assembly peptide-mediated bioorthogonal reaction strategy to bridge the supramolecular self-assembly and AIE field through strain-promoted azide-alkyne cycloaddition (SPAAC) and elucidates that pure type-I membrane-anchoring PSs can be used for cancer therapy via GSDME-mediated pyroptosis.

Receptor-interacting protein kinase 1 confers autophagic promotion of gasdermin E-mediated pyroptosis in aristolochic acid-induced acute kidney injury

Aristolochic acid (AA) exposure is a severe public health concern worldwide. AAs damage the kidney with an inevitable acute phase that is similar to acute kidney injury (AKI). Gasdermin E (GSDME) is abundant in the kidney; thus; it-mediated pyroptosis might be essential in connecting cell death and inflammation and promoting AAs-AKI. However, the role and exact mechanism of pyroptosis in AAs-AKI have not been investigated. In this study, aristolochic acid I (AAI) was used to establish AKI models. The expression and translocation results showed GSDME-mediated pyroptosis in AAI-AKI. Knocking down GSDME attenuated AAI-induced cell death and transcription of proinflammatory cytokines. Mechanistic research inhibiting caspase (casp) 3, casp 8, and casp 9 with specific chemical antagonists demonstrated that GSDME was activated by cleaved casp 3. Furthermore, the kinase activity of upstream receptor-interacting protein kinase 1 (RIPK1) was significantly elevated, and inhibiting RIPK1 with specific inhibitors markedly improved AAI-induced cell damage. In addition, the level of autophagy was obviously increased. Pretreatment with a specific autophagic inhibitor (3-methyladenine) or knockdown of autophagic genes (Atg5 or Atg7) evidently reduced the activity of RIPK1 and downstream apoptosis and pyroptosis, thus attenuating AA-induced cell injury, which suggested that RIPK1 was a novel link conferring autophagic promotion of pyroptosis. These findings reveal GSDME-mediated pyroptosis for the first time in AAI-induced AKI, propose its novel role in the transcription of cytokines, and demonstrate that autophagy promotes pyroptosis via the RIPK1-dependent apoptotic pathway. This study promotes the understanding of the toxic effects and exact mechanisms of AAs. This will contribute to evaluating the environmental risk of AA exposure and might provide potential therapeutic targets for AA-AKI.

EFFECT OF ARTESUNATE TREATMENT ON INTESTINAL INJURY AFTER CARDIOPULMONARY RESUSCITATION IN SWINE.

Intestinal injury is often caused by systemic ischemia-reperfusion injury early after cardiac arrest (CA) and resuscitation. Artesunate (Art) has been confirmed to protect vital organs against diverse of regional I/R injury. This study aimed to investigate the effect of Art on intestinal injury after CA and cardiopulmonary resuscitation (CPR) in swine. Twenty-two swine were randomly divided into three groups: sham (n = 6), CA/CPR (n = 8), and CA/CPR + Art (n = 8). The CA/CPR swine model was established by inducing 9 minutes of untreated ventricular fibrillation (VF) followed by 6 minutes of CPR. Five minutes after resuscitation, 4.8 mg/kg of Art was intravenously administered for 2 hours in the CA/CPR + Art group. Intestinal fatty acid-binding protein (iFABP) and diamine oxidase (DAO) concentrations were compared among the three groups before CA and at 1, 2, 4, and 24 hours after resuscitation. At 24 hours post-resuscitation, intestinal zonula occluden-1(ZO-1), occludin, apoptosis, caspase-3/gasdermin E (GSDME)-mediated pyroptosis proteins concentrations, and proinflammatory cytokine concentrations were examined to evaluate intestinal injury. During CPR, spontaneous circulation was achieved in 7 and 6 swine in the CA/CPR and CA/CPR + Art groups, respectively. Serum iFABP and DAO concentrations were significantly higher and intestinal tissue ZO-1 and occludin concentrations were significantly lower in the CA/CPR and CA/CPR + Art groups than in the sham group. However, Art treatment resulted in markedly improved levels of intestinal injury biomarkers compared with those in the CA/CPR group. Additionally, intestinal apoptosis and concentrations of caspase-3/GSDME-mediated pyroptosis proteins and proinflammatory cytokines were significantly higher in the CA/CPR and CA/CPR + Art groups than in the sham group. However, these variables were significantly lower in the CA/CPR + Art group than in the CA/CPR group. Art treatment effectively alleviates post-resuscitation intestinal injury, possibly by inhibiting the caspase-3/GSDME-mediated pyroptosis pathway in a swine CA and CPR model.

Dual-Responsive Epigenetic Inhibitor Nanoprodrug Combined with Oncolytic Virus Synergistically Boost Cancer Immunotherapy by Igniting Gasdermin E-Mediated Pyroptosis.

Cancer immunotherapy has emerged as a promising approach for the treatment of various cancers. However, the immunosuppressive tumor microenvironment (TME) limits the efficacy of current immunotherapies. In this study, we designed a dual-responsive DNA methyltransferase inhibitor nanoprodrug ACNPs for combination therapy with oncolytic herpes simplex virus (oHSV). We found that the epigenetic inhibitor 5-Azacytidine (5-Aza) upregulated gasdermin E (GSDME) expression at the gene level, whereas the oHSV decreased the ubiquitination and degradation of GSDME to elevate its levels. Based on these observations, we further discovered that ACNPs and oHSV synergistically enhanced GSDME-mediated pyroptosis. Additionally, the combination therapy of ACNPs and oHSV effectively inhibited tumor growth, remodeled the immunosuppressive TME, and improved the efficacy of immune checkpoint blockade (ICB) therapy. These results demonstrate the potential to overcome immunosuppression through synergistic combinations, offering a promising approach for cancer immunotherapy.

Research Progress on the Role of GSDME-mediated Pyroptosis in the Treatment of Lung Cancer

Lung cancer causes a significant threat to human health. Despite considerable advancements in the treatment technologies in recent years, the five-year survival rate for lung cancer patients remains low. In this context, the discovery of pyroptosis, a unique cell death mechanism, offers a novel perspective for exploring new pathways of lung cancer treatment. Particularly, the role of gasdermin E (GSDME) in the process of pyroptosis reveals its tremendous potential in lung cancer therapy. Recent studies have made considerable progress in understanding the role of GSDME-mediated pyroptosis in lung cancer growth, the lung cancer microenvironment, and the effect of GSDME methylation on lung cancer treatment. This paper summarizes these research advancements and analyzes the potential and possible side effects of GSDME-mediated pyroptosis in lung cancer therapy, aiming to provide a theoretical foundation for developing more effective strategies for lung cancer treatment. .

A new insight into the mechanism of dichlorodiphenyltrichloroethane-induced hepatotoxicity based on GSDME-mediated pyroptosis

There have been persistent concerns about the safety risks associated with DDT residues in the environment. Studies have shown that exposure to DDT or its metabolites can cause various liver diseases. However, the mechanisms of liver toxicity haven't been well studied. In our current investigation, we observed that DDT triggers pyroptosis in human liver cells (HL-7702), representing a novel form of programmed cell death. Our results delineated DDT (0–100 μM) induced pyroptosis in HL-7702 cells, which was confirmed through morphological changes, lactate dehydrogenase (LDH) release, gasdermin E (GSDME) cleavage and Annexin-V/PI staining. Knockdown of GSDME reduced cell death and transferred the mode of cell death from pyroptosis to apoptosis. Notably, DDT exposure markedly increased reactive oxygen species (ROS) production, concurrent with c-Jun N-terminal kinase (JNK) phosphorylation. Intervention with a ROS inhibitor or JNK inhibitor SP600125 restored cell viability and hindered GSDME-mediated pyroptosis. Our results firstly demonstrate that DDT suppresses HL-7702 cells growth by inducing pyroptosis mainly through the ROS/JNK/GSDME pathway. These findings not only contribute to an in-depth understanding of DDT toxicity but also open avenues for gaining valuable insights into potential mitigation strategies and therapeutic interventions.

Synergistic induction of mitotic pyroptosis and tumor remission by inhibiting proteasome and WEE family kinases

Mitotic catastrophe (MC), which occurs under dysregulated mitosis, represents a fascinating tactic to specifically eradicate tumor cells. Whether pyroptosis can be a death form of MC remains unknown. Proteasome-mediated protein degradation is crucial for M-phase. Bortezomib (BTZ), which inhibits the 20S catalytic particle of proteasome, is approved to treat multiple myeloma and mantle cell lymphoma, but not solid tumors due to primary resistance. To date, whether and how proteasome inhibitor affected the fates of cells in M-phase remains unexplored. Here, we show that BTZ treatment, or silencing of PSMC5, a subunit of 19S regulatory particle of proteasome, causes G2- and M-phase arrest, multi-polar spindle formation, and consequent caspase-3/GSDME-mediated pyroptosis in M-phase (designated as mitotic pyroptosis). Further investigations reveal that inhibitor of WEE1/PKMYT1 (PD0166285), but not inhibitor of ATR, CHK1 or CHK2, abrogates the BTZ-induced G2-phase arrest, thus exacerbates the BTZ-induced mitotic arrest and pyroptosis. Combined BTZ and PD0166285 treatment (named BP-Combo) selectively kills various types of solid tumor cells, and significantly lessens the IC50 of both BTZ and PD0166285 compared to BTZ or PD0166285 monotreatment. Studies using various mouse models show that BP-Combo has much stronger inhibition on tumor growth and metastasis than BTZ or PD0166285 monotreatment, and no obvious toxicity is observed in BP-Combo-treated mice. These findings disclose the effect of proteasome inhibitors in inducing pyroptosis in M-phase, characterize pyroptosis as a new death form of mitotic catastrophe, and identify dual inhibition of proteasome and WEE family kinases as a promising anti-cancer strategy to selectively kill solid tumor cells.

Differential signalling requirements for RIPK1-dependent pyroptosis in neutrophils and macrophages

TLR4 and TNFR1 signalling promotes potent proinflammatory signal transduction events, thus, are often hijacked by pathogenic microorganisms. We recently reported that myeloid cells retaliate Yersinia blockade of TAK1/IKK signalling by triggering RIPK1-dependent caspase-8 activation that promotes downstream GSDMD and GSDME-mediated pyroptosis in macrophages and neutrophils respectively. However, the upstream signalling events for RIPK1 activation in these cells are not well defined. Here, we demonstrate that unlike in macrophages, RIPK1-driven pyroptosis and cytokine priming in neutrophils are driven through TNFR1 signalling, while TLR4-TRIF signalling is dispensable. Furthermore, we demonstrate that activation of RIPK1-dependent pyroptosis in neutrophils during Yersinia infection requires IFN-γ priming, which serves to induce surface TNFR1 expression and amplify soluble TNF secretion. In contrast, macrophages utilise both TNFR1 and TLR4-TRIF signalling to trigger cell death, but only require TRIF but not autocrine TNFR1 for cytokine production. Together, these data highlight the emerging theme of cell type-specific regulation in cell death and immune signalling in myeloid cells.

Inhibiting caspase-3/GSDME-mediated pyroptosis ameliorates septic lung injury in mice model

Acute lung injury is one of the most serious complications of sepsis, which is a common critical illness in clinic. This study aims to investigate the role of caspase-3/ gasdermin-E (GSDME)-mediated pyroptosis in sepsis-induced lung injury in mice model. Cecal ligation (CLP) operation was used to establish mice sepsis-induced lung injury model. Lung coefficient, hematoxylin and eosin staining and transmission electron microscopy were used to observe the lung injury degree. In addition, caspase-3-specific inhibitor Z-DEVD-FMK and GSDME-derived inhibitor AC-DMLD-CMK were used in CLP model, caspase-3 activity, GSDME immunofluorescence, serum lactate dehydrogenase (LDH) and interleukin-6 (IL-6) levels, TUNEL staining, and the expression levels of GSDME related proteins were detected. The mice in CLP group showed the increased expressions of cleaved-caspase-3 and GSDME-N terminal, destruction of lung structure, and the increases of LDH, IL-6, IL-18 and IL-1β levels, which were improved in mice treated with Z-DEVD-FMK or AC-DMLD-CMK. In conclusion, caspase-3/GSDME mediated pyroptosis is involved in the occurrence of sepsis-induced lung injury in mice model, inhibiting caspase-3 or GSDME can both alleviate lung injury.

GSDME-mediated pyroptosis promotes anti-tumor immunity of neoadjuvant chemotherapy in breast cancer

Paclitaxel and anthracycline-based chemotherapy is one of the standard treatment options for breast cancer. However, only about 6–30% of breast cancer patients achieved a pathological complete response (pCR), and the mechanism responsible for the difference is still unclear. In this study, random forest algorithm was used to screen feature genes, and artificial neural network (ANN) algorithm was used to construct an ANN model for predicting the efficacy of neoadjuvant chemotherapy for breast cancer. Furthermore, digital pathology, cytology, and molecular biology experiments were used to verify the relationship between the efficacy of neoadjuvant chemotherapy and immune ecology. It was found that paclitaxel and doxorubicin, an anthracycline, could induce typical pyroptosis and bubbling in breast cancer cells, accompanied by gasdermin E (GSDME) cleavage. Paclitaxel with LDH release and Annexin V/PI doubule positive cell populations, and accompanied by the increased release of damage-associated molecular patterns, HMGB1 and ATP. Cell coculture experiments also demonstrated enhanced phagocytosis of macrophages and increased the levels of IFN-γ and IL-2 secretion after paclitaxel treatment. Mechanistically, GSDME may mediate paclitaxel and doxorubicin-induced pyroptosis in breast cancer cells through the caspase-9/caspase-3 pathway, activate anti-tumor immunity, and promote the efficacy of paclitaxel and anthracycline-based neoadjuvant chemotherapy. This study has practical guiding significance for the precision treatment of breast cancer, and can also provide ideas for understanding molecular mechanisms related to the chemotherapy sensitivity.

Alleviating Pyroptosis of Intestinal Epithelial Cells to Restore Mucosal Integrity in Ulcerative Colitis by Targeting Delivery of 4-Octyl-Itaconate.

Current therapies primarily targeting inflammation often fail to address the root relationship between intestinal mucosal integrity and the resulting dysregulated cell death and ensuing inflammation in ulcerative colitis (UC). First, UC tissues from human and mice models in this article both emphasize the crucial role of Gasdermin E (GSDME)-mediated pyroptosis in intestinal epithelial cells (IECs) as it contributes to colitis by releasing proinflammatory cytokines, thereby compromising the intestinal barrier. Then, 4-octyl-itaconate (4-OI), exhibiting potential for anti-inflammatory activity in inhibiting pyroptosis, was encapsulated by butyrate-modified liposome (4-OI/BLipo) to target delivery for IECs. In brief, 4-OI/BLipo exhibited preferential accumulation in inflamed colonic epithelium, attributed to over 95% of butyrate being produced and absorbed in the colon. As expected, epithelium barriers were restored significantly by alleviating GSDME-mediated pyroptosis in colitis. Accordingly, the permeability of IECs was restored, and the resulting inflammation, mucosal epithelium, and balance of gut flora were reprogrammed, which offers a hopeful approach to the effective management of UC.

PJA1-mediated suppression of pyroptosis as a driver of docetaxel resistance in nasopharyngeal carcinoma

Chemoresistance is a main reason for treatment failure in patients with nasopharyngeal carcinoma, but the exact regulatory mechanism underlying chemoresistance in nasopharyngeal carcinoma remains to be elucidated. Here, we identify PJA1 as a key E3 ubiquitin ligase involved in nasopharyngeal carcinoma chemoresistance that is highly expressed in nasopharyngeal carcinoma patients with nonresponse to docetaxel-cisplatin-5-fluorouracil induction chemotherapy. We find that PJA1 facilitates docetaxel resistance by inhibiting GSDME-mediated pyroptosis in nasopharyngeal carcinoma cells. Mechanistically, PJA1 promotes the degradation of the mitochondrial protein PGAM5 by increasing its K48-linked ubiquitination at K88, which further facilitates DRP1 phosphorylation at S637 and reduced mitochondrial reactive oxygen species production, resulting in suppression of GSDME-mediated pyroptosis and the antitumour immune response. PGAM5 knockdown fully restores the docetaxel sensitization effect of PJA1 knockdown. Moreover, pharmacological targeting of PJA1 with the small molecule inhibitor RTA402 enhances the docetaxel sensitivity of nasopharyngeal carcinoma in vitro and in vivo. Clinically, high PJA1 expression indicates inferior survival and poor clinical efficacy of TPF IC in nasopharyngeal carcinoma patients. Our study emphasizes the essential role of E3 ligases in regulating chemoresistance and provides therapeutic strategies for nasopharyngeal carcinoma based on targeting the ubiquitin-proteasome system.

Liguzinediol potentiates the metabolic remodeling by activating the AMPK/SIRT3 pathway and represses Caspase-3/GSDME-mediated pyroptosis to ameliorate cardiotoxicity

BackgroundLiguzinediol (Lig) has emerged as a promising candidate for mitigating Doxorubicin (DOX)-induced cardiotoxicity, a significant limitation in the clinical application of this widely used antineoplastic drug known for its efficacy. This study aimed to explore the effects and potential mechanisms underlying Lig’s protective role against DOX-induced cardiotoxicity.MethodsC57BL/6 mice were treated with DOX. Cardiac function changes were observed by echocardiography. Cardiac structure changes were observed by HE and Masson staining. Immunofluorescence was applied to visualize the cardiomyocyte apoptosis. Western blotting was used to detect the expression levels of AMP-activated protein kinase (AMPK), sirtuin 3 (SIRT3), Caspase-3 and gasdermin E N-terminal fragment (GSDME-N). These experiments confirmed that Lig had an ameliorative effect on DOX-induced cardiotoxicity in mice.ResultsThe results demonstrated that Lig effectively countered myocardial oxidative stress by modulating intracellular levels of reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD). Lig reduced levels of creatine kinase (CK) and lactate dehydrogenase (LDH), while ameliorating histopathological changes and improving electrocardiogram profiles in vivo. Furthermore, the study revealed that Lig activated the AMPK/SIRT3 pathway, thereby enhancing mitochondrial function and attenuating myocardial cell apoptosis. In experiments with H9C2 cells treated with DOX, co-administration of the AMPK inhibitor compound C (CC) led to a significant increase in intracellular ROS levels. Lig intervention reversed these effects, along with the downregulation of GSDME-N, interleukin-1β (IL-1β), and interleukin-6 (IL-6), suggesting a potential role of Lig in mitigating Caspase-3/GSDME-mediated pyroptosis.ConclusionThe findings of this study suggest that Lig effectively alleviates DOX-induced cardiotoxicity through the activation of the AMPK/SIRT3 pathway, thereby presenting itself as a natural product with therapeutic potential for preventing DOX-associated cardiotoxicity. This novel approach may pave the way for the development of alternative strategies in the clinical management of DOX-induced cardiac complications.

Celastrol activates caspase-3/GSDME-dependent pyroptosis in tumor cells by inducing endoplasmic reticulum stress

ObjectiveTo investigate the pyroptosis-inducing effects of celastrol on tumor cells and to explore the potential mechanisms involved, specifically focusing on the role of the caspase-3/gasdermin E (GSDME) signaling pathway and the impact of endoplasmic reticulum (ER) stress and autophagy. MethodsNecrostatin-1 (Nec-1), lactate dehydrogenase release (LDH) assay, and Hoechst/propidium iodide (PI) double staining were employed to validate the mode of cell death. Western blot was used to detect the cleavage of GSDME and the expression of light chain 3 (LC3) and BIP. ResultsCelastrol induced cell swelling with large bubbles, which is consistent with the pyroptotic phenotype. Moreover, treatment with celastrol induced GSDME cleavage, indicating the activation of GSDME-mediated pyroptosis. GSDME knockout via CRISPR/Cas9 blocked the pyroptotic morphology of celastrol in HeLa cells. In addition, cleavage of GSDME was attenuated by a specific caspase-3 inhibitor in celastrol-treated cells, suggesting that GSDME activation was induced by caspase-3. Mechanistically, celastrol induced endoplasmic reticulum (ER) stress and autophagy in HeLa cells, and other ER stress inducers produced effects consistent with those of celastrol. ConclusionThese findings suggest that celastrol triggers caspase-3/GSDME-dependent pyroptosis via activation of ER stress, which may shed light on the potential antitumor clinical applications of celastrol.

Maresin1 alleviates neuroinflammation by inhibiting caspase-3/ GSDME-mediated pyroptosis in mice cerebral ischemia-reperfusion model

ObjectiveTo explore the mechanism of Maresin1 in reducing cerebral ischemia-reperfusion injury. Materials and methodsMale C57BL/6 mice were randomly divided (n = 5 in each group), and focal middle cerebral artery occlusion (MCAO) model was used to simulate cerebral ischemia/reperfusion injury. TTC and the Longa score were used to detect the degree of neurological deficits. Western blot was used to detect the expression levels of GSDME, GSDME-N, caspase-3 and cleaved caspase-3 in cerebral ischemic penumbra tissue, and immunofluorescence was used to detect the expression levels of GSDME-N. The mRNA expression levels of GSDME and pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) were detected by RT-PCR. ResultsCompared with sham group, GSDME mRNA levels in MCAO group were significantly increased at 12 h and 24 h after reperfusion, and GSDME and GSDME-N significantly increased at 6–48 h after reperfusion. Compared with sham group, the percentage of infarct size, the Longa score, the mRNA expression levels of IL-1β, IL-6 and TNF-α, and GSDME, GSDME-N, caspase-3 and cleaved caspase-3 in MCAO group was significantly increased. Then, the percentage of infarct size and the Longa score significantly decreased after MaR1 administration, the mRNA expression levels of IL-1β and IL-6 downregulated, and GSDME, GSDME-N, caspase-3 and cleaved caspase-3 were also reduced. After administration of Z-DEVD-FMK(ZDF), the expression of caspase-3, cleaved caspase-3 and GSDME-N was decreased, which in MCAO+MaR1+ZDF group was not statistically significant compared with MCAO+ ZDF group. ConclusionMaresin1 alleviates cerebral ischemia/reperfusion injury by inhibiting pyroptosis mediated by caspase-3/GSDME pathway and alleviating neuroinflammation.

Inhibition of ROS/caspase-3/GSDME-mediated pyroptosis alleviates high glucose-induced injury in AML-12 cells

Diabetic liver injury (DLI) is a chronic complication of the liver caused by diabetes, and its has become one of the main causes of nonalcoholic fatty liver disease (NAFLD). The gasdermin E (GSDME)-dependent pyroptosis signaling pathway is involved in various physiological and pathological processes; however, its role and mechanism in DLI are still unknown. This study was performed to investigate the role of GSDME-mediated pyroptosis in AML-12 cell injury induced by high glucose and to evaluate the therapeutic potential of caspase-3 inhibition for DLI. The results showed that high glucose activated apoptosis by regulating the apoptotic protein levels including Bax, Bcl-2, and enhanced cleavage of caspase-3 and PARP. Notably, some of the hepatocytes treated with high glucose became swollen, accompanied by GSDME-N generation, indicating that pyroptosis was further induced by active caspase-3. Moreover, the effects of high glucose on AML-12 cells could be partly reversed by a reactive oxygen scavenger (NAC) and caspase-3 specific inhibitor (Z-DEVD-FMK), which suggests high glucose induced GSDME-dependent pyroptosis in AML-12 cells through increasing ROS levels and activating caspase-3. In conclusion, our results show that high glucose can induce pyroptosis in AML-12 cells, at least in part, through the ROS/caspase-3/GSDME pathway，and inhibition of caspase-3 can ameliorate high glucose-induced hepatocyte injury, providing an important basis for clarifying the pathogenesis and treatment of DLI.