Cucurbitacin B attenuates osteoarthritis development by inhibiting NLRP3 inflammasome activation and pyroptosis through activating Nrf2/HO-1 pathway.

Osteoarthritis (OA) is a complicated joint disorder characterized by inflammation that causes joint destruction. Cucurbitacin B (CuB) is a naturally occurring triterpenoid compound derived from plants in the Cucurbitaceae family. The aim of this study is to investigate the potential role and mechanisms of CuB in a mouse model of OA. This study identified the key targets and potential pathways of CuB through network pharmacology analysis. In vivo and in vitro studies confirmed the potential mechanisms of CuB in OA. Through network pharmacology, 54 potential targets for CuB in treating OA were identified. The therapeutic potential of CuB is associated with the nod-like receptor pyrin domain 3 (NLRP3) inflammasome and pyroptosis. Molecular docking results indicate a strong binding affinity of CuB to nuclear factor erythroid 2-related factor 2 (Nrf2) and p65. In vitro experiments demonstrate that CuB effectively inhibits the expression of pro-inflammatory factors induced by interleukin-1ß (IL-1ß), including cyclooxygenase-2, inducible nitric oxide synthase, IL-1ß, and IL-18. CuB inhibits the degradation of type II collagen and aggrecan in the extracellular matrix (ECM), as well as the expression of matrix metalloproteinase-13 and a disintegrin and metalloproteinase with thrombospondin motifs-5. CuB protects cells by activating the Nrf2/hemeoxygenase-1 (HO-1) pathway and inhibiting nuclear factor-κB (NF-κB)/NLRP3 inflammasome-mediated pyroptosis. Moreover, in vivo experiments show that CuB can slow down cartilage degradation in an OA mouse model. CuB effectively prevents the progression of OA by inhibiting inflammation in chondrocytes and ECM degradation. This action is further mediated through the activation of the Nrf2/HO-1 pathway to inhibit NF-κB/NLRP3 inflammasome activation. Thus, CuB is a potential therapeutic agent for OA.

NcRNA Regulated Pyroptosis in Liver Diseases and Traditional Chinese Medicine Intervention: A Narrative Review.

Pyroptosis is a novel pro-inflammatory mode of programmed cell death that differs from ferroptosis, necrosis, and apoptosis in terms of its onset and regulatory mechanisms. Pyroptosis is dependent on cysteine aspartate protein hydrolase (caspase)-mediated activation of GSDMD, NLRP3, and the release of pro-inflammatory cytokines, interleukin-1 (IL-1ß), and interleukin-18 (IL-18), ultimately leading to cell death. Non-coding RNA (ncRNA) is a type of RNA that does not encode proteins in gene transcription but plays an important regulatory role in other post-transcriptional links. NcRNA mediates pyroptosis by regulating various related pyroptosis factors, which we termed the pyroptosis signaling pathway. Previous researches have manifested that pyroptosis is closely related to the development of liver diseases, and is essential for liver injury, alcoholic fatty liver disease (ALD), non-alcoholic fatty liver disease (NAFLD), liver fibrosis, and liver cancer. In this review, we attempt to address the role of the ncRNA-mediated pyroptosis pathway in the above liver diseases and their pathogenesis in recent years, and briefly outline that TCM (Traditional Chinese Medicine) intervene in liver diseases by modulating ncRNA-mediated pyroptosis, which will provide a strategy to find new therapeutic targets for the prevention and treatment of liver diseases in the future.

Cistanche phenylethanoid glycosides induce apoptosis and pyroptosis in T-cell lymphoma.

Cistanche deserticola, known for its extensive history in Traditional Chinese Medicine (TCM), is valued for its therapeutic properties. Recent studies have identified its anticancer capabilities, yet the mechanisms underlying these properties remain to be fully elucidated. In this study, we determined that a mixture of four cistanche-derived phenylethanoid glycosides (CPhGs), echinacoside, acteoside, 2-acetylacteoside, and cistanoside A, which are among the main bioactive compounds in C. deserticola, eliminated T-cell lymphoma (TCL) cells by inducing apoptosis and pyroptosis in vitro and attenuated tumor growth in vivo in a xenograft mouse model. At the molecular level, these CPhGs elevated P53 by inhibiting the SIRT2-MDM2/P300 and PI3K/AKT carcinogenic axes and activating PTEN-Bax tumor-suppressing signaling. Moreover, CPhGs activated noncanonical and alternative pathways to trigger pyroptosis. Interestingly, CPhGs did not activate canonical NLRP3-caspase-1 pyroptotic signaling pathway; instead, CPhGs suppressed the inflammasome factor NLRP3 and the maturation of IL-1ß. Treatment with a caspase-1/4 inhibitor and silencing of Gasdermin D (GSDMD) or Gasdermin E (GSDME) partially rescued CPhG-induced cell death. Conversely, forced expression of NLRP3 restored cell proliferation. In summary, our results indicate that CPhGs modulate multiple signaling pathways to achieve their anticancer properties and perform dual roles in pyroptosis and NLRP3-driven proliferation. This study offers experimental support for the potential application of CPhGs in the treatment of TCL.

The Scutellaria-Coptis herb couple and its active small-molecule ingredient wogonoside alleviate cytokine storm by regulating the CD39/NLRP3/GSDMD signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: A drug pair is a fundamental aspect of traditional Chinese medicine prescriptions. Scutellaria baicalensis Georgi and Coptis chinensis Franch, commonly used as an herb couple (SBCC), are representative heat-clearing and dampness-drying drugs. They possess functions such as clearing heat, drying dampness, purging fire, and detoxifying. These herbs are used in both traditional and modern medicine for treating inflammation. AIM OF THE STUDY: This study investigated the effects of SBCC on cytokine storm syndrome (CSS) and explored its potential regulatory mechanism. MATERIALS AND METHODS: We assessed the impact of SBCC in a sepsis-induced acute lung injury mouse model by administering an intraperitoneal injection of LPS (15 mg/kg). The cytokine levels in the serum and lungs, the wet-to-dry ratio of the lungs, and lung histopathological changes were evaluated. The macrophages in the lung tissue were examined through transmission electron microscopy. Western blot was used to measure the levels of the CD39/NLRP3/GSDMD pathway-related proteins. Immunofluorescence imaging was used to assess the activation of pro-caspase-1 and ASC and their interaction. AMP-Glo™ assay was used to screen for active ingredients in SBCC targeting CD39. One of the ingredients was selected, and its effect on cell viability was assessed. We induced inflammation in macrophages using LPS + ATP and detected the levels of proinflammatory factors. The images of cell membrane large pores were captured using scanning electron microscopy, the interaction between NLRP3 and ASC was detected using immunofluorescence imaging, and the levels of CD39/NLRP3/GSDMD pathway-related proteins were assessed using Western blot. RESULTS: SBCC administration effectively mitigated LPS-induced cytokine storm, pulmonary edema and lung injury. Furthermore, it repressed the programmed death of lung tissue macrophages by inhibiting the NLRP3/GSDMD pyroptosis pathway and regulating the CD39 purinergic pathway. Based on the results of the AMP-Glo™ assay, we selected wogonoside for further valuation. Wogonoside alleviated LPS + ATP-induced inflammatory damage by regulating the inhibiting the NLRP3/GSDMD pyroptosis pathway and regulating the CD39 purinergic pathway. However, its effect on NLRP3 is not mediated though CD39. CONCLUSION: SBCC and its active small-molecule ingredient, wogonoside, improved CSS by regulating the NLRP3/GSDMD pyroptosis pathway and its upstream CD39 purinergic pathway. It is essential to note that the regulatory effect of wogonoside on NLRP3 is not mediated by CD39.

A thermoresponsive nanocomposite integrates NIR-II-absorbing small molecule with lonidamine for pyroptosis-promoted synergistic immunotherapy.

Photothermal immunotherapy is regarded as the ideal cancer therapeutic modality to against malignant solid tumors; however, its therapeutic benefits are often modest and require improvement. In this study, a thermoresponsive nanoparticle (BTN@LND) composed of a photothermal agent (PTA) and pyroptosis inducer (lonidamine) were developed to enhance immunotherapy applications. Specifically, our "two-step" donor engineering strategy produced the strong NIR-II-absorbing organic small-molecule PTA (BTN) that exhibited high NIR-II photothermal performance (ε1064 = 1.51 × 104 M-1 cm-1, η = 75.8%), and this facilitates the diagnosis and treatment of deep tumor tissue. Moreover, the fabricated thermally responsive lipid nanoplatform based on BTN efficiently delivered lonidamine to the tumor site and achieved spatiotemporal release triggered by the NIR-II photothermal effect. In vitro and in vivo experiments demonstrated that the NIR-II photothermal therapy (PTT)-mediated on-demand release of cargo effectively faciliated tumor cell pyroptosis, thereby intensifying the immunogenic cell death (ICD) process to promote antitumor immunotherapy. As a result, this intelligent component bearing photothermal and chemotherapy can maximally suppress the growth of tumors, thus providing a promising approach for pyroptosis/NIR-II PTT synergistic therapy against tumors.

Hyperthermia and cisplatin combination therapy promotes caspase-8 accumulation and activation to enhance apoptosis and pyroptosis in cancer cells.

BACKGROUND: Hyperthermia can play a synergistic role with chemotherapy in combination therapy. Although the association between caspase activation, apoptosis, and pyroptosis have been published for both cisplatin (CDDP) and hyperthermia therapies independently, the interactions between these molecular pathways in combination therapy are unknown. The present study aimed to investigate the possible interactions between caspase 8 activation, apoptosis, and pyroptosis in combination therapy. METHODS: Cells were treated with CDDP (15 µg/ml), followed by hyperthermia at optimized temperature (42.5 °C) in water-bath. After combination therapy, cell viability was analyzed by CCK-8, and cell death was analyzed by Annexin-V-FITC/PI and caspases activation. Immuno-staining and co-immuno-precipitation were used to examine the interaction between p62 and caspase-8. Pyroptosis was investigated by western blotting and transmission electron microscopy. E3 ligase Cullin 3 was knockdown by siRNA. In addition, caspase-8 activation was modulated by CRISPR-Cas9 gene-editing or pharmacological inhibition. RESULTS: Combination therapy promoted K63-linked polyubiquitination of caspase-8 and cellular accumulation of caspase-8. In turn, polyubiquitinated caspase-8 interacted with p62 and led to the activation of caspase-3. Knockdown of the E3 ligase Cullin 3 by siRNA reduced caspase-8 polyubiquitination and activation. In addition, combination therapy induced release of the pore-forming N-terminus from gasdermins and promoted pyroptosis along with caspase-8 accumulation and activation. Knockdown of caspase-8 by CRISPR/Cas9 based gene editing reduced the sensitivity of tumor cells to apoptosis and pyroptosis. CONCLUSIONS: Our study presented a novel mechanism in which hyperthermia synergized with chemotherapy in promoting apoptosis and pyroptosis in a caspase-8 dependent manner.

Aqueous extract of Epimedium sagittatum (Sieb. et Zucc.) Maxim. induces liver injury in mice via pyroptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Epimedium sagittatum (Sieb. et Zucc.) Maxim. has been used traditionally in Asia. It can dispel wind and cold, tonify the kidney, and strengthen bones and tendons. However, adverse effects of E. sagittatum have been reported, and the underlying mechanisms remain unclear. AIM OF THE STUDY: This study aimed to investigate liver injury caused by an aqueous extract of E. sagittatum in Institute of Cancer Research (ICR) mice and explore its potential mechanisms. MATERIALS AND METHODS: Dried E. sagittatum leaves were decocted in water to prepare aqueous extracts for ultra-high performance liquid chromatography analysis. Mice were administered an aqueous extract of E. sagittatum equivalent to either 3 g raw E. sagittatum/kg or 10 g raw E. sagittatum/kg once daily via intragastric injection for three months. The liver weights and levels of the serum biochemical parameters including alanine transaminase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), total bilirubin (TBIL), and alkaline phosphatase were measured. Hematoxylin-eosin staining was performed for histopathology. Apoptosis was detected using the TUNEL apoptosis assay kit. IL-1ß was detected using ELISA kits. Proteomics was used to identify the differentially expressed proteins. Western blot analysis was performed to determine the levels of proteins significantly affected by the aqueous extract of E. sagittatum. RESULTS: E. sagittatum treatment increased the liver weights and liver coefficients, and ALT and AST levels significantly increased (p < 0.05). A high dose of E. sagittatum significantly increased LDH and TBIL levels (p < 0.05). Ruptured cell membranes and multiple sites of inflammatory cell infiltration were also observed. No evidence of apoptosis was observed. IL-1ß levels were significantly increased (p < 0.05). The expressions of PIK3R1, p-MAP2K4, p-Jun N-terminal kinase (JNK)/JNK, p-c-Jun, VDAC2, Bax, and CYC were upregulated, whereas that of Bcl-2 was inhibited by E. sagittatum. The expression of cleaved caspase-1 was significantly increased; however, its effects on GSDMD and GSDMD-N were significantly decreased. The expression levels of cleaved caspase-3 and its effector proteins GSDME and GSDME-N significantly increased. CONCLUSIONS: Our results suggest that the aqueous extract of E. sagittatum induces liver injury in ICR mice after three months of intragastric injection via inflammatory pyroptosis.

Aloe-emodin alleviates cerebral ischemia-reperfusion injury by regulating microglial polarization and pyroptosis through inhibition of NLRP3 inflammasome activation.

BACKGROUND: Microglial activation plays a crucial role in injury and repair after cerebral ischemia, and microglial pyroptosis exacerbates ischemic injury. NOD-like receptor protein 3 (NLRP3) inflammasome activation has an important role in microglial polarization and pyroptosis. Aloe-emodin (AE) is a natural anthraquinone compound originated from rhubarb and aloe. It exerts antioxidative and anti-apoptotic effects during cerebral ischemia/reperfusion (I/R) injury. However, whether AE affects microglial polarization, pyroptosis, and NLRP3 inflammasome activation remains unknown. PURPOSE: This study aimed to explore the effects of AE on microglial polarization, pyroptosis, and NLRP3 inflammasome activation in the cerebral infarction area after I/R. METHODS: The transient middle cerebral artery occlusion (tMCAO) and oxygen-glucose deprivation/re-oxygenation (OGD/R) methods were used to create cerebral I/R models in vivo and in vitro, respectively. Neurological scores and triphenyl tetrazolium chloride and Nissl staining were used to assess the neuroprotective effects of AE. Immunofluorescence staining, quantitative polymerase chain reaction and western blot were applied to detect NLRP3 inflammasome activation and microglial polarization and pyroptosis levels after tMCAO or OGD/R. Cell viability and levels of interleukin (IL)-18 and IL-1ß were measured. Finally, MCC950 (an NLRP3-specific inhibitor) was used to evaluate whether AE affected microglial polarization and pyroptosis by regulating the activation of the NLRP3 inflammasome. RESULTS: AE improved neurological function scores and reduced the infarct area, brain edema rate, and Nissl-positive cell rate following I/R injury. It also showed a protective effect on BV-2 cells after OGD/R. AE inhibited microglial pyroptosis and induced M1 to M2 phenotype transformation and suppressed microglial NLRP3 inflammasome activation after tMCAO or OGD/R. The combined administration of AE and MCC950 had a synergistic effect on the inhibition of tMCAO- or OGD/R-induced NLRP3 inflammasome activation, which subsequently suppressed microglial pyroptosis and induced microglial phenotype transformation. CONCLUSION: AE exerts neuroprotective effects by regulating microglial polarization and pyroptosis through the inhibition of NLRP3 inflammasome activation after tMCAO or OGD/R. These findings provide new evidence of the molecular mechanisms underlying the neuroprotective effects of AE and may support the exploration of novel therapeutic strategies for cerebral ischemia.

Reniformin A suppresses non-small cell lung cancer progression by inducing TLR4/NLRP3/caspase-1/GSDMD-dependent pyroptosis.

Pyroptosis is an inflammatory form of programmed cell death that plays an important role in regulating tumor progression. Reniformin A (RA) is a natural compound isolated from the medicinal herb Isodon excisoides that has been applied as folk medicine in the treatment of esophageal cancer. However, whether RA has an individual function in cancer and the molecular mechanisms remain unclear. Here, we show that in non-small-cell lung cancer (NSCLC), RA inhibits tumor growth by functioning as a pyroptosis inducer to promote TLR4/NLRP3/caspase-1/GSDMD axis. Specially, RA treatment increased Toll-like receptor 4 (TLR4) protein expression level by enhancing the TLR4 stability. Based on the molecular docking, we identified that RA directly bound to TLR4 to activate the NLRP3 inflammasome and promote pyroptosis in A549 cells. Moreover, TLR4 is essential for RA-induced pyroptosis, and loss of TLR4 abolished RA-induced pyroptosis and further reduced the inhibitory effect of RA on NSCLC. In vivo experiments confirmed that RA inhibited the growth of lung tumors in mice by affecting pyroptosis in a dose-dependent manner. Furthermore, TLR4 knockdown abolished RA-induced pyroptosis and inhibited the effect of RA chemotherapy in vivo. In conclusion, we propose that RA has a significant anticancer effect in NSCLC by inducing TLR4/NLRP3/caspase-1/GSDMD-mediated pyroptosis, which may provide a potential strategy for the treatment of NSCLC.

From growth promotion to intestinal inflammation alleviation: Unraveling the potential role of Lactobacillus rhamnosus GCC-3 in juvenile grass carp (Ctenopharyngodon idella).

Lactobacillus rhamnosus is a probiotic, which not only promotes the growth of animals, but also has anti-inflammatory effects. However, the mechanism by which Lactobacillus rhamnosus regulates intestinal immunity is not well comprehended. Hence, the study aimed to research how Lactobacillus rhamnosus affects the intestinal immunity using juvenile grass carp (Ctenopharyngodon idella) as a model. We selected 1800 juvenile grass carp for testing. They were divided into six treatments and fed with six gradients of Lactobacillus rhamnosus GCC-3 (0.0, 0.5, 1.0, 1.5, 2.0, 2.5 g/kg) for 70 days. Enteritis was subsequently induced with dextroside sodium sulfate. Results indicated that dietary Lactobacillus rhamnosus GCC-3 addition improved growth performance. Meanwhile, appropriate levels of Lactobacillus rhamnosus GCC-3 alleviated excessive inflammatory response by down-regulating the expression of TLR4 and NOD receptors, up-regulating the expression of TOR, and then down-regulating the expression of NF-κB. Additionally, appropriate Lactobacillus rhamnosus GCC-3 improved intestinal immunity by reducing pyroptosis triggered by NLRP3 inflammasome and mediated by GSDME. Furthermore, 16 S rRNA sequencing showing appropriate levels of Lactobacillus rhamnosus GCC-3 increased Lactobacillus and Bifidobacterium abundance and decreased Aeromonas abundance. These results suggest that Lactobacillus rhamnosus GCC-3 can alleviate intestinal inflammation through down-regulating NF-κB and up-regulating TOR signaling pathways, as well as by inhibiting pyroptosis.

Engineering a hyaluronic acid-encapsulated tumor-targeted nanoplatform with sensitized chemotherapy and a photothermal effect for enhancing tumor therapy.

Chemotherapy remains one of the most widely used cancer treatment modalities in clinical practice. However, the characteristic microenvironment of solid tumors severely limits the anticancer efficacy of chemotherapy. In addition, a single treatment modality or one death pathway reduces the antitumor outcome. Herein, tumor-targeting O2 self-supplied nanomodules (CuS@DOX/CaO2-HA) are proposed that not only alleviate tumor microenvironmental hypoxia to promote the accumulation of chemotherapeutic drugs in tumors but also exert photothermal effects to boost drug release, penetration and combination therapy. CuS@DOX/CaO2-HA consists of copper sulfide (CuS)-loaded calcium peroxide (CaO2) and doxorubicin (DOX), and its surface is further modified with HA. CuS@DOX/CaO2-HA underwent photothermal treatment to release DOX and CaO2. Hyperthermia accelerates drug penetration to enhance chemotherapeutic efficacy. The exposed CaO2 reacts with water to produce Ca2+, H2O2 and O2, which sensitizes cells to chemotherapy through mitochondrial damage caused by calcium overload and a reduction in drug efflux via the alleviation of hypoxia. Moreover, under near infrared (NIR) irradiation, CuS@DOX/CaO2-HA initiates a pyroptosis-like cell death process in addition to apoptosis. In vivo, CuS@DOX/CaO2-HA demonstrated high-performance antitumor effects. This study provides a new strategy for synergistic enhancement of chemotherapy in hypoxic tumor therapy via combination therapy and multiple death pathways.

Riboflavin Attenuates Fluoride-Induced Testicular Injury via Interleukin 17A-Mediated Classical Pyroptosis.

Male reproductive toxicity of fluoride is of great concern worldwide, yet the underlying mechanism is unclear. Pyroptosis is a novel mode of inflammatory cell death, and riboflavin with anti-inflammatory properties has the potential to protect against fluoride damage. However, it is unknown whether pyroptosis is involved in fluoride-induced testicular injury and riboflavin intervention. Here, we first found that riboflavin could alleviate fluoride-caused lower sperm quality and damaged testicular morphology by reducing pyroptosis based on a model of ICR mice treated with NaF (100 mg/L) and/or riboflavin supplementation (40 mg/L) via drinking water for 13 weeks. And then, together with the results of in vitro Leydig cell modelsm it was confirmed that the pyroptosis occurs predominantly through classical NLRP3/Caspase-1/GSDMD pathway. Furthermore, our results reveal that interleukin-17A mediates the process of pyroptosis in testes induced by fluoride and riboflavin attenuation according to the results of our established models of riboflavin- and/or fluoride-treated IL-17A knockout mice. The results not only declare a new mechanism by which fluoride induces testicular injury via interleukin 17A-mediated classical pyroptosis but also provide evidence for the potential clinical application of riboflavin as an effective therapy for fluoride toxicity.

Mahuang Fuzi Xixin decoction alleviates allergic rhinitis by inhibiting NLRP3/Caspase-1/GSDMD-N-mediated pyroptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Allergic rhinitis (AR) is a prevalent nasal inflammatory disorder, and pyroptosis plays a crucial role in aggravating AR. Current medications for AR treatment still have deficiencies, and finding new agents is of great interest. Mahuang Fuzi Xixin decoction (MFXD), an ancient Chinese medicine, is now commonly used to treat AR, which has anti-inflammatory and immunomodulatory effects, but its underlying mechanism is unknown. AIM OF THIS STUDY: This study aims to evaluate the effects of MFXD on AR and explore its potential mechanisms in view of the regulatory effect on pyroptosis. METHODS: MFXD, Mahuang, Fuzi, and Xixin water extracts were analyzed using ultra high performance liquid chromatography-Orbitrap-high-resolution accurate mass spectrometry. In in vivo study, the effects of MFXD on AR treatment were evaluated in an ovalbumin-induced mouse model. Mice were administered saline (control and model groups), MFXD (1.375, 2.75 g/kg), and dexamethasone (2.5 mg/kg) for 13 days. AR symptoms were evaluated by blinded observers. Immunoglobulin E (IgE) and histamine levels were measured using enzyme-linked immunosorbent assays. Expression of pyroptosis-related proteins (NLRP3, ASC, Caspase-1 p10/p20, GSDMD-N and IL-1ß) in AR mouse nasal mucosa were estimated by immunohistochemistry. In in vivtro study, the effects of MFXD on pyroptosis were assessed in human nasal epithelial cells (HNEpCs) stimulated with lipopolysaccharide (LPS) and adenosine triphosphate (ATP), and incubated with MFXD (12.5, 25, and 50 µg/mL). Pyroptosis-related protein expression was measured by western blotting. RESULTS: Thirty-three compounds in MFXD were identified, including ephedrine, pseudoephedrine, higenamine, aconine, aconitine, benzoylmesaconitine, benzoylhypaconine and hypaconitine. In the in vivo study, oral taken of MFXD/dexamethasone significantly ameliorated AR symptoms, reduced swelling of the nasal mucosa, and decreased the levels of IgE and histamine in AR mice serum. MFXD/dexamethasone attenuated histopathological changes and reduced the expression of pyroptosis-related proteins in nasal mucosa, indicating the inhibitory effect on nasal epithelial pyroptosis. In the in vitro study, MFXD (50 µg/mL) significantly alleviated cytotoxicity, protected cells from swelling and rupture, and downregulated the expression of pyroptosis-related proteins in LPS/ATP-induced HNEpCs. CONCLUSION: MFXD suppressed nasal epithelial pyroptosis by inhibiting the NLRP3/Caspase-1/GSDMD-N signaling pathway, which alleviates AR. Our results offer valuable insights into potential AR therapies and provide evidence for the clinical utilization of MFXD to treat AR.

Neobractatin induces pyroptosis of esophageal cancer cells by TOM20/BAX signaling pathway.

BACKGROUND: Emerging evidence suggests that pyroptosis, a form of programmed cell death, has been implicated in cancer progression. The involvement of specific proteins in pyroptosis is an area of growing interest. TOM20, an outer mitochondrial membrane protein, has recently garnered attention for its potential role in pyroptosis. Our previous study found that NBT could induce pyroptosis by ROS/JNK pathway in esophageal cancer cells. PURPOSE: This study aims to investigate whether NBT induces pyroptosis and verify whether such effects are involved in up-regulation of TOM20 in esophageal cancer cells. METHODS: The University of ALabama at Birmingham CANcer data analysis Portal (UALCAN) was used to analyze the clinical significance of GSDME in esophageal cancer. MTT assay, morphological observation and Western blot were performed to verify the roles of TOM20 and BAX in NBT-induced pyroptosis after CRISPR-Cas9-mediated knockout. Immunofluorescence was used to determine the subcellular locations of BAX and cytochrome c. MitoSOX Red was employed to assess the mitochondrial reactive oxygen species (ROS) level. KYSE450 and TOM20 knockout KYSE450-/- xenograft models were established to elucidate the mechanisms involved in NBT-induced cell death. RESULTS: In this study, NBT effectively upregulated the expression of TOM20 and facilitated the translocation of BAX to mitochondria, which promoted the release of cytochrome c from mitochondria to the cytoplasm, leading to the activation of caspase-9 and caspase-3, and finally induced pyroptosis. Knocking out TOM20 by CRISPR-Cas9 significantly inhibited the expression of BAX and the downstream BAX/caspase-3/GSDME pathway, which attenuated NBT-induced pyroptosis. The elevated mitochondrial ROS level was observed after NBT treatment. Remarkably, the inhibition of ROS by N-acetylcysteine (NAC) effectively suppressed the activation of TOM20/BAX pathway. Moreover, in vivo experiments demonstrated that NBT exhibited potent antitumor effects in both KYSE450 and TOM20 knockout KYSE450-/- xenograft models. Notably, the attenuated antitumor effects and reduced cleavage of GSDME were observed in the TOM20 knockout model. CONCLUSION: These findings reveal that NBT induces pyroptosis through ROS/TOM20/BAX/GSDME pathway, which highlight the therapeutic potential of targeting TOM20 and GSDME, providing promising prospects for the development of innovative and effective treatment approaches for esophageal cancer.

Huang Qin decoction increases SLC6A4 expression and blocks the NFκB-mediated NLRP3/Caspase1/GSDMD pathway to disrupt colitis-associated carcinogenesis.

Huang Qin decoction (HQD) is a traditional Chinese medicine formula for treating colitis, but the effects and molecular mechanism of action of HQD in colitis-associated carcinogenesis (CAC) are still unclear. Therefore, we aimed to determine the beneficial effects of HQD on CAC in mice and to reveal the underlying mechanism involved. AOM/DSS was used to induce CAC in mice, and the effects of HQD on tumorigenesis in mice were examined (with mesalazine serving as a positive control). Mesalazine or HQD treatment alleviated body weight loss and decreased the disease activity index in mice induced by AOM/DSS. Mesalazine or HQD treatment also suppressed the shortening of colon tissue length, the number of tumors, and the infiltration of inflammatory cells. The genes targeted by HQD were predicted and verified, followed by knockout experiments. Elevated SLC6A4 and inhibited serotonin production and inflammation were observed in HQD-treated mice. HQD inhibited the NFκB and NLRP3/caspase1/GSDMD pathways. The therapeutic effect of HQD was diminished in SLC6A4-deficient AOM/DSS mice. Additionally, the downregulation of SLC6A4 mitigated the inhibitory effect of HQD-containing serum on MODE-K cell pyroptosis. Our findings suggest that SLC6A4 is a pivotal regulator of HQD-alleviated CAC via its modulation of the NLRP3/caspase1/GSDMD pathway.

Americanin B inhibits pyroptosis in lipopolysaccharide-induced septic encephalopathy mice through targeting NLRP3 protein.

BACKGROUND: Sepsis is considered as a severe illness due to its high mortality. Sepsis can cause septic encephalopathy, thus leading to brain injury, behavioral and cognitive dysfunction. Pyroptosis is a type of regulated cell death (RCD) and takes a crucial part in occurrence and development of sepsis. Americanin B (AMEB) is a lignan compounds, which is extracted from Vernicia fordii. In our previous study, AMEB could inhibit microglial activation in inflammatory cell model. However, the function of AMEB in septic encephalopathy mice is uncertain. It would be worthwhile to ascertain the role and mechanism of AMEB in sepsis. PURPOSE: Current study designs to certify the relationship between pyroptosis and septic encephalopathy, and investigate whether AMEB can restrain NOD-like receptor pyrin domain-containing 3 (NLRP3) inflammasome activation and restrict pyroptosis by targeting NLRP3 in septic mice model. STUDY DESIGN: C57BL/6 mice were utilized to perform sepsis model in vivo experiments. BV-2 cell lines were used for in vitro experiments. METHODS: In vivo sepsis model was established by lipopolysaccharide (LPS) intraperitoneal injection in male C57BL/6 J mice and in vitro model was exposed by LPS plus ATP in BV-2 cells. The survival rate was monitored on the corresponding days. NLRP3, apoptosis associated Speck-like protein (ASC), caspase-1, GasderminD (GSDMD), interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) level were detected by western blotting and immunofluorescence analysis. Molecular docking, cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) experiments, RNAi transfection and quantitative real-time PCR were applied to confirm the potential target of AMEB. RESULTS: The results suggested that AMEB could rise survival percentage and lighten brain injury in LPS-induced sepsis mice. In addition, AMEB could inhibit pyroptosis and the activiation of NLRP3 inflammasome. The inhibiting function of AMEB on the activiation of NLRP3 inflammasome is weakened following si-NLRP3 transfection. Moreover, AMEB exerted anti-pyroptosis effect via targeting NLRP3 protein. CONCLUSIONS: Our findings first indicate NLRP3 is an effective druggable target for septic encephalopathy related brain injury, and also provide a candidate-AMEB for the treatment of septic encephalopathy. These emerging findings on AMEB in models of sepsis suggest an innovative approach that may be beneficial in the prevention of septic encephalopathy.

Total paeony glycoside relieves neuroinflammation to exert antidepressant effect via the interplay between NLRP3 inflammasome, pyroptosis and autophagy.

BACKGROUND: Depression is a common mental illness characterised by abnormal and depressed emotions. Total paeony glycoside (TPG) is a naturally active saponin extracted from the traditional Chinese medicine Radix Paeoniae rubra. However, the antidepressant and neuroinflammatory effects of TPG have not been thoroughly studied. PURPOSE: To study the therapeutic potential of TGP in depression caused by neuronal injury and neuroinflammation and to explore the mechanism of TGP and the relationship between the NLRP3 inflammasome, pyroptosis, and autophagy. STUDY DESIGN: A chronic unpredictable mild stress (CUMS)-induced depression model and a cell model of corticosterone (CORT)-induced hippocampal neuron injury were established to evaluate the therapeutic effects of TPG. METHODS: The composition of TPG was analysed using high-performance liquid chromatography and mass spectrometry. The effects of TPG and fluoxetine on depression-like behaviour, neuronal injury, neuroinflammation, pyroptosis, and mitochondrial autophagy in the mice models were evaluated. RESULTS: TGP alleviated depression-like behaviours in mice and inhibited hippocampal neuronal apoptosis. The secretion of inflammatory cytokines was significantly reduced in CORT-induced hippocampal neuron cells and in the serum of a mouse model of CUMS-induced depression. In addition, TGP treatment reduced the levels of NLRP3 family pyrin structural domains, including NLRP3, pro-caspase-1, caspase-1, and IL-1ß, and the pyroptosis related proteins such as GSDMD-N. Importantly, TPG attenuated mitochondrial dysfunction, promoted the clearance of damaged mitochondria, and the activation of mitochondrial autophagy, which reduced ROS accumulation and NLRP3 inflammasome activation. An in-depth study observed that the regulatory effect of TPG on autophagy was attenuated by the autophagy inhibitor 3-methyladenine (3-MA) in vitro and in vivo. However, administration of the caspase-1 inhibitor Belnacasan (VX-765) successfully inhibited pyroptosis and showed a synergistic therapeutic effect with TPG. CONCLUSION: These results indicate that TPG can repair neuronal damage by activating autophagy, restoring mitochondrial function, and reducing inflammation-mediated pyroptosis, thereby playing an important role in the alleviation of neuroinflammation and depression. This study suggests new potential drugs and treatment strategies for neuroinflammation-related diseases and depression.

Luteolin rescues postmenopausal osteoporosis elicited by OVX through alleviating osteoblast pyroptosis via activating PI3K-AKT signaling.

BACKGROUND: Recently, osteoblast pyroptosis has been proposed as a potential pathogenic mechanism underlying osteoporosis, although this remains to be confirmed. Luteolin (Lut), a flavonoid phytochemical, plays a critical role in the anti-osteoporosis effects of many traditional Chinese medicine prescriptions. However, its protective impact on osteoblasts in postmenopausal osteoporosis (PMOP) has not been elucidated. PURPOSE: This research aimed to determine the effect of Lut in ameliorating PMOP by alleviating osteoblast pyroptosis and sustaining osteogenesis. STUDY DESIGN: This research was designed to investigate the novel mechanism of Lut in alleviating PMOP both in cell and animal models. METHODS: Ovariectomy-induced PMOP models were established in mice with/without daily gavaged of 10 or 20 mg/kg body weight Lut. The impact of Lut on bone microstructure, metabolism and oxidative stress was evaluated with 0.104 mg/kg body weight Estradiol Valerate Tablets daily gavaged as positive control. Network pharmacological analysis and molecular docking were employed to investigate the mechanisms of Lut in PMOP treatment. Subsequently, the impacts of Lut on the PI3K/AKT axis, oxidative stress, mitochondria, and osteoblast pyroptosis were assessed. In vitro, cultured MC3T3-E1(14) cells were exposed to H2O2 with/without Lut to examine its effects on the PI3K/AKT signaling pathway, osteogenic differentiation, mitochondrial function, and osteoblast pyroptosis. RESULTS: Our findings demonstrated that 20 mg/kg Lut, similar to the positive control drug, effectively reduced systemic bone loss and oxidative stress, and enhanced bone metabolism induced by ovariectomy. Network pharmacological analysis and molecular docking indicated that the PI3K/AKT axis was a potential target, with oxidative stress response and nuclear membrane function being key mechanisms. Consequently, the effects of Lut on the PI3K/AKT axis and pyroptosis were investigated. In vivo data revealed that the PI3K/AKT axis was deactivated following ovariectomy, and Lut restored the phosphorylation of key proteins, thereby reactivating the axis. Additionally, Lut alleviated osteoblast pyroptosis and mitochondrial abnormalities induced by ovariectomy. In vitro, Lut intervention mitigated the inhibition of the PI3K/AKT axis and osteogenesis, as well as H2O2-induced pyroptosis. Furthermore, Lut attenuated ROS accumulation and mitochondrial dysfunction. The effects of Lut, including osteogenesis restoration, anti-pyroptosis, and mitochondrial maintenance, were all reversed with LY294002 (a PI3K/AKT pathway inhibitor). CONCLUSION: In summary, Lut could improve mitochondrial dysfunction, alleviate GSDME-mediated pyroptosis and maintain osteogenesis via activating the PI3K/AKT axis, offering a new therapeutic strategy for PMOP.

Protective Effect of Silibinin on Lipopolysaccharide-Induced Endotoxemia by Inhibiting Caspase-11-Dependent Cell Pyroptosis.

OBJECTIVE: To explore the protective effect and the underlying mechanism of silibinin (SIB), one of the active compounds from Silybum marianum (L.) Gaertn in endotoxemia. METHODS: Mouse peritoneal macrophage were isolated via intraperitoneally injection of BALB/c mice with thioglycolate medium. Cell viability was assessed using the cell counting kit-8, while cytotoxicity was determined through lactate dehydrogenase cytotoxicity assay. The protein expressions of interleukin (IL)-1 α, IL-1 ß, and IL-18 were determined by enzyme-linked immunosorbent assay. Intracellular lipopolysaccharide (LPS) levels were measured by employing both the limulus amoebocyte lysate assay and flow cytometry. Additionally, proximity ligation assay was employed for the LPS and caspase-11 interaction. Mice were divided into 4 groups: the control, LPS, high-dose-SIB (100 mg/kg), and low-dose-SIB (100 mg/kg) groups (n=8). Zebrafish were divided into 4 groups: the control, LPS, high-dose-SIB (200 εmol/L), and low-dose-SIB (100 εmol/L) groups (n=30 for survival experiment and n=10 for gene expression analysis). The expression of caspase-11, gasdermin D (GSDMD), and N-GSDMD was determined by Western blot and the expressions of caspy2, gsdmeb, and IL-1 ß were detected using quantitative real-time PCR. Histopathological observation was performed through hematoxylineosin staining, and protein levels in bronchoalveolar lavage fluid were quantified using the bicinchoninicacid protein assay. RESULTS: SIB noticeably decreased caspase-11 and GSDMD-mediated pyroptosis and suppressed the secretion of IL-1 α, IL-1 ß, and IL-18 induced by LPS (P<0.05). Moreover, SIB inhibited the translocation of LPS into the cytoplasm and the binding of caspase-11 and intracellular LPS (P<0.05). SIB also attenuated the expression of caspase-11 and N-terminal fragments of GSDMD, inhibited the relative cytokines, prolonged the survival time, and up-regulated the survival rate in the endotoxemia models (P<0.05). CONCLUSIONS: SIB can inhibit pyroptosis in the LPS-mediated endotoxemia model, at least in part, by inhibiting the caspase-11-mediated cleavage of GSDMD. Additionally, SIB inhibits the interaction of LPS and caspase-11 and inhibits the LPS-mediated up-regulation of caspase-11 expression, which relieves caspase-11-dependent cell pyroptosis and consequently attenuates LPS-mediated lethality.

Astragaloside IV Alleviates Doxorubicin-Induced Cardiotoxicity by Inhibiting Cardiomyocyte Pyroptosis through the SIRT1/NLRP3 Pathway.

Doxorubicin (DOX) is a powerful anthracycline antineoplastic drug used to treat a wide spectrum of tumors. However, its clinical application is limited due to cardiotoxic side effects. Astragaloside IV (AS IV), one of the major compounds present in aqueous extracts of Astragalus membranaceus, possesses potent cardiovascular protective properties, but the underlying molecular mechanisms are unclear. Thus, the aim of this study was to investigate the effect of AS IV on DOX-induced cardiotoxicity (DIC). Our findings revealed that DOX induced pyroptosis through the caspase-1/gasdermin D (GSDMD) and caspase-3/gasdermin E (GSDME) pathways. AS IV treatment significantly improved the cardiac function and alleviated myocardial injury in DOX-exposed mice by regulating intestinal flora and inhibiting pyroptosis; markedly suppressed the levels of cleaved caspase-1, N-GSDMD, cleaved caspase-3, and N-GSDME; and reversed DOX-induced downregulation of silent information regulator 1 (SIRT1) and activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome in mice. The SIRT1 inhibitor EX527 significantly blocked the protective effects of AS IV. Collectively, our results suggest that AS IV protects against DIC by inhibiting pyroptosis through the SIRT1/NLRP3 pathway.