GSDMB involvement in the pathogenesis of abdominal aortic aneurysm through regulation of macrophage non-canonical pyroptosis.

Abdominal aortic aneurysm (AAA) is a dangerous condition affecting the aorta. Macrophage pyroptosis, phenotypic transformation, and apoptosis of aortic smooth muscle cells (ASMCs) are pivotal mechanisms in AAA pathogenesis. This study explores how Gasdermin B (GSDMB) regulates macrophage non-canonical pyroptosis and its impact on the phenotypic transformation and apoptosis of ASMCs, thereby unveiling the role of GSDMB in AAA pathogenesis. Immunofluorescence analysis was used to assess the expression levels and localization of GSDMB, cysteinyl aspartate-specific protease-4 (Caspase-4), and N-terminal of cleaved GSDMD (N-GSDMD) in AAA tissues. A cell model that mimics macrophage non-canonical pyroptosis was established by treating THP-1 cells with lipopolysaccharide (LPS). THP-1 cells with reduced or increased GSDMB were generated using small interfering RNA (siRNA) or plasmids. Co-culture experiments involving THP-1 cells and HASMCs were conducted to explore the impact of GSDMB on HASMCs. The mitochondrial reactive oxygen species (mtROS) scavenger Mito-TEMPO lowered mtROS levels in THP-1 cells. Our findings revealed that GSDMB was significantly upregulated in AAA macrophages, which was accompanied by robust non-canonical pyroptosis. THP-1 cells showed non-canonical pyroptosis in response to LPS, which was accompanied by an increase in GSDMB. Further research demonstrated that altering GSDMB, either by knockdown or overexpression, can affect macrophage non-canonical pyroptosis as well as the phenotypic transformation and apoptosis of HASMCs. LPS-induced non-canonical pyroptosis in THP-1 cells was associated with an increase in mtROS, whereas Mito-TEMPO effectively decreased non-canonical pyroptosis and the expression of GSDMB. These findings suggest that GSDMB plays a role in AAA macrophage non-canonical pyroptosis, which influences the phenotypic transformation and apoptosis of HASMCs. The mtROS-Dynamin-Related Protein 1 (Drp1) axis is likely to regulate the GSDMB-mediated non-canonical pyroptosis.

[Study on the risk factors of coal workers' pneumoconiosis and the mechanism of pyroptosis in peripheral blood].

Objective: To explore the risk factors of coal workers' pneumoconiosis, reveal the molecular mechanism of pyroptosis in peripheral blood of coal workers' pneumoconiosis patients, and provide new strategies and potential diagnostic biomarkers for the treatment of the disease. Methods: From January 1, 2020 to December 31, 2022, workers with suspected occupational diseases who were diagnosed with coal workers' pneumoconiosis in the Third People's Hospital of Xinjiang Uygur Autonomous Region were included in the study, including 77 patients with coal workers' pneumoconiosis stage Ⅰ, 10 patients with stage Ⅱ, 6 patients with stage Ⅲ, and 49 workers with dust-free lung disease as the control group. General information of the subjects was collected, blood samples were collected for routine blood and blood biochemical results, and plasma levels of interleukin (IL) -1ß and IL-18 were measured. Combined with the results of clinical examination, multi-factor ordered logistic regression analysis was carried out to evaluate the influencing factors of coal workers' pneumoconiosis. At the same time, the expression of pyroptosis related proteins in blood cells was detected to reveal the molecular mechanism of coal workers' pneumoconiosis. Results: All 142 subjects were male, with an average age of (51.65±6.31) years old and an average working age of (15.94±9.38) years. There were significant differences in smoking age (F=4.95, P=0.003) and lunch break distribution (H=8.84, P=0.031) among all groups. The hemoglobin content of stage Ⅰ patients was higher than that of stage Ⅱ patients, and the neutrophil percentage of stage Ⅲ patients was higher than that of the other 3 groups (P<0.05). The levels of total bilirubin and indirect bilirubin in stage Ⅰ patients were higher than those in control group, while the erythrocyte sedimentation rate in stage Ⅱ patients was higher than that in the other 3 groups (P<0.05). The levels of IL-18 and IL-1ß in stage Ⅲ of coal workers' pneumoconiosis were higher than those in the other 3 groups (P<0.05). Multiple logistic regression analysis showed that smoking age (OR=1.03, 95%CI: 1.00-1.06) and IL-1ß level (OR=4.61, 95%CI: 1.59-13.32) were independent risk factors for coal workers' pneumoconiosis (P<0.05). Compared with the control group, the expression levels of nucleotide-binding of oligomeric domain-like receptor protein 3 (NLRP3), Caspase-1, GSDMD, Caspase-4 and other proteins in stage Ⅲ of coal workers' pneumoconiosis were significantly increased (P<0.05) . Conclusion: Smoking age is a risk factor for coal workers' pneumoconiosis, IL-1ß may be a potential biomarker for the diagnosis of coal workers' pneumoconiosis, and pyroptosis may play a role in the development of peripheral inflammation of coal workers' pneumoconiosis.

The inhibiting effect of Aspirin Triggered-Resolvin D1 in non-canonical pyroptosis in rats with acute keratitis.

PURPOSE: To investigate the effect of Aspirin Triggered-Resolvin D1 (AT-RvD1) as an anti-pyroptosis and anti-inflammatory agent on lipopolysaccharide (LPS) induced acute keratitis in Wistar rats. METHODS: Acute keratitis in rats were induced by LPS stromal injection. Inflammatory reaction was measured by clinical score and histological observations. The non-canonical pyroptosis, the role of AT-RvD1 and Docosahexaenoic Acid (DHA) on non-canonical pyroptosis, were verified by quantification real-time PCR (qRT-PCR) and Western-blot. Besides, Human corneal epithelial cells (HCECs) primed with LPS, were stimulated with Nigericin, AT-RvD1 and necrosulfonamide (NSA), a Gasdermin-D (GSDMD) inhibitor separately. CCK-8 tests and flow cytometry were conducted to evaluate the cell viability and death ratio. And the marker of non-canonical pyroptosis were verified by Western blot. RESULTS: AT-RvD1 and DHA both alleviated the inflammation of rat cornea through inhibiting the expression of Caspase-11 and p30 which was triggered by LPS. Meanwhile, the activation of Caspase-4 and p30 were also significantly suppressed by AT-RvD1 in vitro, which is consistent with the results in rats. CONCLUSIONS: The non-canonical pyroptosis signaling pathways played an important role in rats with acute keratitis. In addition, AT-RvD1 can exert as an anti-inflammatory activity by inhibiting the non-canonical pyroptosis. Hence, it may be a promising and safe agent in treating acute keratitis.

Role of non-canonical pyroptosis in sepsis and other inflammatory diseases. / éžç»å ¸é€”å¾„ç»†èƒžç„¦äº¡åœ¨è„“æ¯’è¡€ç—‡ç­‰ç‚Žç—‡æ€§ç–¾ç— ä¸­çš„ä½œç”¨.

As a form of new programmed cell death, pyroptosis is divided into a canonical pyroptosis pathway and a non-canonical pyroptosis pathway. In recent years, it is reported that non-canonical pyroptosis is closely related to inflammatory reactions, which directly affects the occurrence, development, and outcome of sepsis, inflammatory bowel disease, respiratory disease, nerve system inflammatory disease, and other inflammatory diseases. When the cells were infected with Gram-negative bacteria or lipopolysaccharide (LPS), it can induce the activation of cysteinyl aspartate specific proteinase(caspase)-4/5/11 and directly bind to the cells to cleave gasdermin D (GSDM-D) into the active amino-terminus of GSDM-D. The amino-terminus of GSDM-D with membrane punching activity migrates to the cell membrane, triggering the rupture of the cell membrane, and the cell contents discharge, leading to the occurrence of non-canonical pyroptosis. After activation of caspase-11, it also promotes the canonical pyroptosis, activates and releases interleukin-1ß and interleukin-18, which aggravated inflammation. Caspase-4/5/11, GSDM-D, Toll-like receptor 4 and high mobility group protein B1 are the key molecules of the non-canonical pyroptosis. Exploring the mechanisms of non-canonical pyroptosis and the related research progresses in inflammatory diseases intensively is of great significance for clinical prevention and treatment of the relevant diseases.

NEDD4 lactylation promotes APAP induced liver injury through Caspase11 dependent non-canonical pyroptosis.

Caspase-11 detection of intracellular lipopolysaccharide mediates non-canonical pyroptosis, which could result in inflammatory damage and organ lesions in various diseases such as sepsis. Our research found that lactate from the microenvironment of acetaminophen-induced acute liver injury increased Caspase-11 levels, enhanced gasdermin D activation and accelerated macrophage pyroptosis, which lead to exacerbation of liver injury. Further experiments unveiled that lactate inhibits Caspase-11 ubiquitination by reducing its binding to NEDD4, a negative regulator of Caspase-11. We also identified that lactates regulated NEDD4 K33 lactylation, which inhibits protein interactions between Caspase-11 and NEDD4. Moreover, restraining lactylation reduces non-canonical pyroptosis in macrophages and ameliorates liver injury. Our work links lactate to the exquisite regulation of the non-canonical inflammasome, and provides a basis for targeting lactylation signaling to combat Caspase-11-mediated non-canonical pyroptosis and acetaminophen-induced liver injury.

The Role and Mechanism of Pyroptosis and Potential Therapeutic Targets in Sepsis: A Review.

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Recently was been found that pyroptosis is a unique form of proinflammatory programmed death, that is different from apoptosis. A growing number of studies have investigated pyroptosis and its relationship with sepsis, including the mechanisms, role, and relevant targets of pyroptosis in sepsis. While moderate pyroptosis in sepsis can control pathogen infection, excessive pyroptosis can lead to a dysregulated host immune response and even organ dysfunction. This review provides an overview of the mechanisms and potential therapeutic targets underlying pyroptosis in sepsis identified in recent decades, looking forward to the future direction of treatment for sepsis.