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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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024. Published by Elsevier GmbH.)

The present study investigated the mechanism underlying Toll-like receptor 4 (TLR4)-mediated stimulation of hypoxia-inducible factor-1α (HIF-1α) activity and its association with reactive oxygen species (ROS) in cervical cancer cells. SiHa cells were cultured and randomized to control, lipopolysaccharide (LPS), methyl-β-cyclodextrin (MβCD)+LPS, ammonium pyrrolidinedithiocarbamate (PDTC)+LPS, ST2825+LPS and small interfering (si) RNA TLR4+LPS treatment groups. Cell proliferation was quantified using an MTT assay, cell cloning was performed using soft agar colony formation and HIF-1α expression was detected by immunocytochemical staining and western blot analyses. Dichloro-dihydro-fluorescein diacetate and lucigenin luminescence assays were used to detect alterations in ROS and nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase content, respectively. Co-localization of TLR4 and HIF-1α was detected by immunofluorescence staining and observed using fluorescence microscopy. Compared with the control group, cell proliferation was enhanced in the LPS-treated group and was not altered in the PDTC+LPS treatment group. Cell proliferation was reduced in all other treatment groups (P<0.05). Compared with the LPS group, cell proliferation decreased in all other groups. Compared with the PDTC+LPS treatment group, cell proliferation significantly decreased when LPS was co-administered with ST2825, siTLR4 and MβCD (P<0.01). Treatment with MβCD+LPS exhibited an increased inhibitory effect on cell activity and proliferation. Compared with the control group, HIF-1α expression was enhanced following treatment with LPS, although it decreased when LPS was co-administered with ST2825, siTLR4 and MβCD (P<0.05). HIF-1α expression decreased following treatment with ST2825, siTLR4, MβCD and PDTC+LPS, compared with treatment with LPS alone. Compared with the PDTC+LPS group, HIF-1α activity decreased when LPS was co-administered with ST2825, siTLR4 and MβCD. NADPH oxidase and ROS levels increased in cells treated with LPS, compared with the control group, at 24 and 12 h following treatment, respectively, and decreased at 12 h when LPS was co-administered with ST2825, siTLR4 and MβCD. There was no difference between the LPS and PDTC+LPS groups with respect to NADPH and ROS levels. Compared with the PDTC+LPS group, NADPH oxidase activity and ROS content decreased when LPS was co-administered with ST2825, siTLR4 and MβCD. NADPH oxidase activity and ROS content were lowest in the MβCD+LPS treatment group, and immunofluorescent staining demonstrated that TLR4 was localized to the cell surface and HIF-1α was primarily localized to the cytoplasm. TLR4 was co-expressed with HIF-1α in cervical cancer cells. The results of the present study suggested that TLR4 signaling primarily promoted HIF-1α activity via activation of lipid rafts/NADPH oxidase redox signaling and may be associated with the initiation and progression of cervical cancer. This promoting effect was stronger in TLR4/lipid rafts/NADPH oxidase pathway than that in TLR4-NF-κB signaling pathway. Therefore, the TLR4/lipid raft-associated redox signal may be a target for therapeutic intervention to prevent the growth of cervical cancer.

Sepsis-associated acute liver injury contributes to the pathogenesis of multiple organ dysfunction syndrome and is associated with increased mortality. Currently, no specific therapeutics for sepsis-associated liver injury are available. With excess levels of reactive oxygen species (ROS) being implicated as key players in sepsis-induced liver injury, we hypothesize that ROS-responsive nanoparticles (NPs) formed via the self-assembly of diblock copolymers of poly(ethylene glycol) (PEG) and poly(propylene sulfide) (PPS) may function as an effective drug delivery system for alleviating sepsis-induced liver injury by preferentially releasing drug molecules at the disease site. However, there are no reports available on the biocompatibility and effect of PEG-b-PPS-NPs in vivo. Herein, this platform was tested for delivering the promising antioxidant therapeutic molecule melatonin (Mel), which currently has limited therapeutic efficacy because of its poor pharmacokinetic properties. The mPEG-b-PPS-NPs efficiently encapsulated Mel using the oil-in-water emulsion technique and provided sustained, on-demand release that was modulated in vitro by the hydrogen peroxide concentration. Animal studies using a mouse model of sepsis-induced acute liver injury revealed that Mel-loaded mPEG-b-PPS-NPs are biocompatible and much more efficacious than an equivalent amount of free drug in attenuating oxidative stress, the inflammatory response, and subsequent liver injury. Accordingly, this work indicates that mPEG-b-PPS-NPs show potential as an ROS-mediated on-demand drug delivery system for improving Mel bioavailability and treating oxidative stress-associated diseases such as sepsis-induced acute liver injury., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Hemorrhagic shock/resuscitation involves overwhelming reactive oxygen species (ROS) that cause oxidative stress, inflammation, and subsequent tissue injury. We investigated the effects of the potent antioxidant carboxyfullerene (C 3 ) on acute liver injury during hemorrhage shock/resuscitation. C 3 infusion reduced the alanine aminotransferase (ALT) activity, methemoglobin content, malondialdehyde content, myeloperoxidase activity and expression levels of tumor necrosis factor -α and interleukin-6; it increased superoxide dismutase activity in the liver. The histologic injury score and apoptotic index were also markedly decreased after C 3 treatment compared with the vehicle group. Additionally, C 3 -treated rats showed a significant decrease in nuclear factor-κB DNA binding capacity, which was preceded by reduced phosphorylation of the nuclear factor κB (NF-κB) p65 subunit in the liver. C 3 nanoparticles ameliorate oxidative stress, the inflammatory response, and subsequent acute liver injury after hemorrhagic shock/resuscitation. These protective effects appear to be mediated through the inhibition of the nuclear factor-κB pathway. C 3 treatment may be a promising strategy to improve tissue injury in hemorrhagic shock/resuscitation., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Aim: To explore the potential therapeutic effect of yttrium oxide nanoparticles (Y2O3 NPs) on fulminant hepatic failure. Materials & methods: RAW264.7 cells and a lipopolysaccharide/D-galactosamine-induced hepatic failure murine model were used to assess the effects of Y2O3 NPs. Results: Y2O3 NPs exhibited anti-inflammatory activity by scavenging cellular reactive oxygen species and dampening reactive oxygen species-mediated NF-κB activation in vitro. A single intraperitoneal administration of Y2O3 NPs (30 mg/kg) enhanced hepatic antioxidant status and reduced oxidative stress and inflammatory response in lipopolysaccharide/galactosamine-induced mice. Y2O3 NPs also attenuated hepatic NF-κB activation, cell apoptosis and liver injury. Conclusion: Y2O3 NP administration could be used as a novel therapeutic strategy for treating fulminant hepatic failure and oxidative stress-related diseases. [ABSTRACT FROM AUTHOR]

Background Oxidative stress induced by hemorrhagic shock (HS) is known to initiate a systemic inflammatory response, which leads to subsequent acute lung injury. This study is aimed to assess the efficacy of exendin-4 (Ex-4) in attenuating lung injury in a rat model of HS and resuscitation (HS/R). Methods HS was induced in sodium pentobarbital–anesthetized adult male Wistar rats by withdrawing blood to maintain a mean arterial pressure of 30-35 mm Hg for 50 min. Then, the animals received Ex-4 (5 μg/kg) or vehicle (saline) intravenously and were resuscitated with a volume of normal saline 1.5 times that of the shed blood volume. Mean arterial pressure was measured throughout the experiment, and acid-base status, oxidative stress, inflammation, and lung injury were evaluated at 2 h after resuscitation. Results Ex-4 infusion reduced the methemoglobin content, the malondialdehyde content, the myeloperoxidase activity, and the expression of tumor necrosis factor-α and interleukin-6 in the lungs. The histologic injury was also markedly decreased in the Ex-4 group compared with the vehicle group. Conclusions Ex-4 ameliorates the oxidative stress, inflammatory response, and subsequent acute lung injury occurring after HS/R. Although future studies are required to elucidate the underlying mechanism, our results indicate that Ex-4 infusion may be a promising strategy for improving lung injury in the treatment of HS. [ABSTRACT FROM AUTHOR]

There is an urgent medical need to develop effective therapies that can ameliorate damage to the radiation-exposed hematopoietic system. Nanozymes with robust antioxidant properties have a therapeutic potential for mitigating radiation-induced hematopoietic injury. However, enhancing nanozyme recruitment to injured tissues in vivo while maintaining their catalytic activity remains a great challenge. Herein, we present the design and preparation of a biomimetic nanoparticle, a mesenchymal stem cell membrane camouflaged Prussian blue nanozyme (PB@MSCM), which exhibits biocompatible surface properties and demonstrates enhanced injury site-targeting towards the irradiated murine bone marrow niche. Notably, the constructed PB@MSCM possessed redox enzyme-mimic catalytic activity and could scavenge overproduced reactive oxygen species in the irradiated bone marrow cells, both in vitro and ex vivo. More importantly, the administration of PB@MSCM significantly mitigated hematopoietic cell apoptosis and accelerated the regeneration of hematopoietic stem and progenitor cells. Our findings provide a new targeted strategy to improve nanozyme therapy in vivo and mitigate radiation-induced hematopoietic injury. [ABSTRACT FROM AUTHOR]

Endothelial activation elicited by inflammatory agents is regarded as a key event in the pathogenesis of several vascular inflammatory diseases. In the present study, the inhibitory effects and underlying mechanism of C-type natriuretic peptide (CNP) on LPS-induced endothelial activation were examined in human umbilical vein endothelial cells (HUVECs). The effect of CNP on adhesion molecule expression was assessed using quantitative real-time RT-PCR and western blotting analyses. The nuclear factor-κB (NF-κB), MAPK, and PI3K/Akt signaling pathways in LPS-stimulated HUVECs were investigated using western blotting analyses, and the production of intracellular reactive oxygen species (ROS) was measured using a fluorescence method. Pretreatment with CNP inhibited LPS-induced expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, E-selectin, and P-selectin in a concentration-dependent manner. CNP suppressed the phosphorylation of p65 and NF-κB activation in LPS-stimulated cells. Moreover, CNP reduced ERK1/2 and p38 phosphorylation induced by LPS but not JNK. Furthermore, CNP induced Akt phosphorylation and activation of hemeoxygenase-1 (HO-1) expression. CNP significantly inhibited the production of intracellular ROS. These results suggest that CNP effectively attenuated LPS-induced endothelial activation by inhibiting the NF-κB and p38 signaling pathways, eliminating LPS-induced intracellular ROS production, and activating the PI3K/Akt/HO-1 pathway in HUVECs; thereby, demonstrating that CNP may be a potential therapeutic target for the treatment of sepsis and inflammatory vascular diseases. [ABSTRACT FROM AUTHOR]