OBJECTIVES: Psoriasis is associated with lipid metabolism disorders, but the underlying mechanisms remain unclear. This study aims to investigate the role of trimethylamine N-oxide (TMAO) in lipid metabolism dysregulation in psoriasis. METHODS: An imiquimod (IMQ)-induced psoriasis-like mouse model was used to assess lipid metabolism parameters, TMAO levels, and liver flavin monooxygenase 3 (FMO3) mRNA expression. Blood samples from healthy individuals and psoriatic patients were collected to measure serum TMAO levels and lipid profiles. To clarify the role of TMAO in the lipid metabolism disorder of mice with psoriasis model, exogenous TMAO, choline, or 3,3-dimethyl-1-butanol (DMB) were administered via intraperitoneal injections or diet in IMQ-treated mice. Liver tissues from the mouse models were subjected to RNA sequencing to identify TMAO-regulated signaling pathways. RESULTS: IMQ-induced psoriatic mice exhibited abnormal glucose, insulin, and lipid levels. IMQ treatment also downregulated the hepatic mRNA expression of glucose transporter 2 (Glut2) and silence information regulator 1 (Sirt1), while upregulating glucose transporter 4 (Glut4) and peroxisome proliferator-activated receptor gamma (PPARγ). Elevated serum TMAO levels were observed in both psoriatic patients and IMQ-treated mice. Additionally, liver FMO3 mRNA expression was increased in the psoriatic mouse model. In patients, TMAO levels positively correlated with Psoriasis Area and Severity Index (PASI) scores, serum triglyceride (TG), and total cholesterol (TC) levels. The intraperitoneal injection of TMAO exacerbated lipid dysregulation in IMQ-treated mice. A choline-rich diet further aggravated lipid abnormalities and liver injury in psoriatic mice, whereas DMB treatment alleviated these effects. RNA-Seq analysis demonstrated that TMAO upregulated hepatic microRNA-122 (miR-122), which may suppress the expression of gremlin 2 (GREM2), thus contributing to lipid metabolism disorder. CONCLUSIONS TMAO may promote lipid metabolism dysregulation in psoriasis by modulating the hepatic miR-122/GREM2 pathway.
Animals ; Methylamines/blood* ; Mice ; Psoriasis/chemically induced* ; Lipid Metabolism/drug effects* ; Humans ; Male ; Liver/metabolism* ; Female ; Oxygenases/genetics* ; Disease Models, Animal ; Lipid Metabolism Disorders/etiology* ; Adult ; Mice, Inbred C57BL

OBJECTIVES: Psoriasis is a chronic inflammatory skin disease often accompanied by comorbidities such as hyperglycemia, insulin resistance, and obesity. Acitretin, as a second-generation retinoid, is used in the treatment of psoriasis. This study aims to explore the role of acitretin on glucose and lipid metabolism in psoriasis. METHODS: HepG2 cells were treated with acitretin under high- or low-glucose conditions. mRNA and protein expression levels of glucose transport-related genes were evaluated using real-time reverse transcription PCR (real-time RT-PCR) and Western blotting. Glucose uptake was analyzed by flow cytometry, and intracellular lipid droplet formation was assessed via Oil Red O staining. Healthy adult female BALB/C mice were randomly divided into 3 groups: a control group, an imiquimod (IMQ)-induced psoriasis model group (IMQ group), and an acitretin treatment group. Skin lesions and inflammatory markers were examined, along with changes in body weight, plasma glucose/lipid levels, and transcription of metabolic genes. Islets were isolated from normal and psoriasis-induced mice, and the effect of acitretin on insulin secretion was evaluated in vitro. RESULTS: Acitretin treatment increased glucose uptake and lipid droplet synthesis of HepG2 in high-glucose environment, with elevated transcription levels of glucose transport-related genes GLUT1 and GLUT4. Transcription of gluconeogenesis-related gene G6pase decreased, while transcription levels of glycogen synthesis-related genes AKT1 and GSY2 increased (all P<0.05), while acitretin inhibits glucose uptake and promotes gluconeogenesis in low-glucose environment. In vivo experiments revealed that compared with the control group, the blood glucose level in the IMQ group was significantly decreased (P<0.05), while acitretin treatment partially restored glucose homeostasis and alleviated weight loss. Ex vivo culture of islets from psoriatic mice revealed that acitretin reduced elevated insulin secretion and downregulated PDX-1 expression, while upregulating glucose homeostasis gene SIRT1 and insulin sensitivity gene PPARγ (all P<0.05). These findings suggest that acitretin plays a critical role in improving islet function and restoring islet homeostasis. CONCLUSIONS Acitretin helps maintain the balance between hepatic glycogenesis and gluconeogenesis, enhances insulin sensitivity, and improves pancreatic islet function, thereby promoting systemic and cellular glucose homeostasis.
Acitretin/therapeutic use* ; Psoriasis/drug therapy* ; Animals ; Imiquimod ; Humans ; Glucose/metabolism* ; Homeostasis/drug effects* ; Mice ; Lipid Metabolism/drug effects* ; Mice, Inbred BALB C ; Female ; Hep G2 Cells ; Disease Models, Animal

OBJECTIVES: Lymph node metastasis in papillary thyroid cancer (PTC) is closely associated with tumor recurrence and patient survival. However, current technologies have limited sensitivity in detecting occult cervical lymph node metastases. Identifying accurate molecular markers for predicting PTC metastasis holds significant clinical value. This study aims to analyze WNT10A expression in PTC and its clinical significance, and to explore the role of WNT10A gene knockdown in PTC cell proliferation, invasion, and metastasis. METHODS: The expression of WNT10A in thyroid carcinoma was analyzed using the Gene Expression Profiling Interactive Analysis (GEPIA) and University of Alabama at Birminghara Cancer data analysis Portal (UALCAN) databases. Real-time RT-PCR was used to measure WNT10A mRNA levels in tumor and adjacent normal tissues from 32 PTC patients. Immunohistochemistry was conducted on 158 PTC specimens to assess WNT10A protein expression and its correlation with clinicopathological features. In vitro experiments were performed using K1 and TPC-1 cell lines. Cell proliferation was assessed using the Celigo system and methyl thiazolyl tetrazolium (MTT) assays; apoptosis was measured via flow cytometry; invasion and metastasis were evaluated using scratch and Transwell assays. A xenograft model was established in nude mice to observe tumor growth, and tumor weight and volume were compared between cell lines. Differentially expressed genes regulated by WNT10A were identified via mRNA sequencing, followed by Gene Ontology (GO) and ingenuity pathway analysis (IPA). Real-time PCR and Western blotting were used to validate the effects of WNT10A on key downstream mRNA and protein in the Tec kinase signaling pathway. RESULTS: WNT10A mRNA expression was significantly higher in thyroid cancer tissues compared to adjacent normal tissues according to GEPIA and UALCAN (both P<0.01). The real-time RT-PCR result showed that WNT10A mRNA expression in PTC tissues was high than that in adjacent tissues (P<0.01). Immunohistochemistry revealed significantly higher WNT10A protein expression in PTC tissues compared to adjacent tissues (P<0.01), and its expression correlated with multifocality, extrathyroidal invasion, and lymph node metastasis. WNT10A knockdown significantly inhibited proliferation, altered cell cycle distribution, and increased apoptosis in K1 and TPC-1 cells (all P<0.01). WNT10A silencing also reduced migration and invasion abilities in both cell lines. In vivo, WNT10A knockdown in TPC-1 cells suppressed tumor formation in nude mice. GO analysis and IPA suggested that the Tec kinase signaling pathway was a key downstream target of WNT10A. RT-PCR and Western blotting confirmed that WNT10A knockdown downregulated the expression of key genes (STAT3, MAPK8, TNFRSF21, and AKT2) in this pathway. CONCLUSIONS WNT10A is highly expressed in PTC and is associated with tumor proliferation, invasion, and metastasis. Its tumor-promoting effects may be mediated through suppression of the Tec kinase signaling pathway.
Humans ; Cell Proliferation ; Thyroid Cancer, Papillary/pathology* ; Thyroid Neoplasms/metabolism* ; Animals ; Wnt Proteins/metabolism* ; Neoplasm Invasiveness ; Mice ; Cell Line, Tumor ; Female ; Male ; Mice, Nude ; Apoptosis ; Lymphatic Metastasis ; Middle Aged ; Cell Movement ; Adult

OBJECTIVES: Metastasis is the primary cause of death in osteosarcoma, and current clinical treatments remain limited. BRD4, a key epigenetic regulator, has shown therapeutic promise in various cancers through its inhibition. However, the mechanistic role of BRD4 in osteosarcoma remains poorly understood. This study aims to elucidate the molecular mechanisms by which BRD4 regulate osteosarcoma progression and to explore novel therapeutic strategies. METHODS: Immunofluorescence was used to assess BRD4 expression levels in a tissue microarray containing 80 osteosarcoma samples from different patients. The Gene Expression Omnibus (GEO) dataset (GSE42352, containing survival data from 88 osteosarcoma patients) was downloaded to perform Kaplan-Meier survival analysis based on BRD4 gene expression levels. In vivo, an orthotopic intramedullary osteosarcoma model was established using HOS cells in C57 mice, followed by treatment with varying doses of the BRD4 inhibitor (+)-JQ1. Micro-CT, 3D reconstruction of bone tissue, and HE staining were employed to evaluate pathological changes in bone and intestinal lymph nodes. In vitro, cell viability was measured using the methyl thiazolyl tetrazolium (MTT) assay, while colony formation and Transwell assays assessed proliferative and invasive capacities. Chromatin-bound BRD4 was analyzed via co-immunoprecipitation combined with mass spectrometry (Co-IP/MS), and O-GlcNAc glycosylation sites and glycan chains of BRD4 were identified using Co-IP with Nano-LC MS/MS. Real-time PCR and Western blotting were used to analyze the relative mRNA and protein expression levels of target genes, respectively. RESULTS: BRD4 was positively expressed in 61.25% (49/80) of osteosarcoma tissues. Patients with high BRD4 expression exhibited significantly shorter survival times (P<0.05). In the orthotopic mouse model, intervention with (+)-JQ1, a potent and commonly used BETi, significantly inhibited tumor growth in vivo and reduced bone destruction (P<0.05). (+)-JQ1 treatment significantly suppressed the proliferation (P<0.001), invasion (P<0.001), and migration (P<0.05) of HOS cells. In osteosarcoma cells, BRD4 exhibited O-GlcNAc modifications at both N- and C- C-termini, particularly at Thr73, which is essential for protein stability. This modification also contributed to the activation of the EGFR tyrosine kinase inhibitor resistance pathway (KEGG Pathway: hsa01521). (+)-JQ1 treatment displaced BRD4 from enhancers and downregulated the transcription of pathway-related genes, such as EGFR and PDGFC, thereby suppressing the malignant behavior of osteosarcoma cells. CONCLUSIONS BRD4 promotes osteosarcoma progression via O-GlcNAc modification at Thr73 and plays a crucial role in tumor growth and metastasis.
Osteosarcoma/drug therapy* ; Humans ; Transcription Factors/metabolism* ; Animals ; Cell Cycle Proteins ; Mice ; Bone Neoplasms/drug therapy* ; Azepines/pharmacology* ; Cell Line, Tumor ; Cell Proliferation/drug effects* ; Triazoles/pharmacology* ; Mice, Inbred C57BL ; Nuclear Proteins/metabolism* ; Gene Expression Regulation, Neoplastic ; Male ; Bromodomain Containing Proteins

OBJECTIVES: Osteoarthritis (OA) and sarcopenia are significant health concerns in the elderly, substantially impacting their daily activities and quality of life. However, the relationship between them remains poorly understood. This study aims to uncover common biomarkers and pathways associated with both OA and sarcopenia. METHODS: Gene expression profiles related to OA and sarcopenia were retrieved from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between disease and control groups were identified using R software. Common DEGs were extracted via Venn diagram analysis. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted to identify biological processes and pathways associated with shared DEGs. Protein-protein interaction (PPI) networks were constructed, and candidate hub genes were ranked using the maximal clique centrality (MCC) algorithm. Further validation of hub gene expression was performed using 2 independent datasets. Receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive value of key genes for OA and sarcopenia. Mouse models of OA and sarcopenia were established. Hematoxylin-eosin and Safranin O/Fast Green staining were used to validate the OA model. The sarcopenia model was validated via rotarod testing and quadriceps muscle mass measurement. Real-time reverse transcription PCR (real-time RT-PCR) was employed to assess the mRNA expression levels of candidate key genes in both models. Gene set enrichment analysis (GSEA) was conducted to identify pathways associated with the selected shared key genes in both diseases. RESULTS: A total of 89 common DEGs were identified in the gene expression profiles of OA and sarcopenia, including 76 upregulated and 13 downregulated genes. These 89 DEGs were significantly enriched in protein digestion and absorption, the PI3K-Akt signaling pathway, and extracellular matrix-receptor interaction. PPI network analysis and MCC algorithm analysis of the 89 common DEGs identified the top 17 candidate hub genes. Based on the differential expression analysis of these 17 candidate hub genes in the validation datasets, AEBP1 and COL8A2 were ultimately selected as the common key genes for both diseases, both of which showed a significant upregulation trend in the disease groups (all P<0.05). The value of area under the curve (AUC) for AEBP1 and COL8A2 in the OA and sarcopenia datasets were all greater than 0.7, indicating that both genes have potential value in predicting OA and sarcopenia. Real-time RT-PCR results showed that the mRNA expression levels of AEBP1 and COL8A2 were significantly upregulated in the disease groups (all P<0.05), consistent with the results observed in the bioinformatics analysis. GSEA revealed that AEBP1 and COL8A2 were closely related to extracellular matrix-receptor interaction, ribosome, and oxidative phosphorylation in OA and sarcopenia. CONCLUSIONS AEBP1 and COL8A2 have the potential to serve as common biomarkers for OA and sarcopenia. The extracellular matrix-receptor interaction pathway may represent a potential target for the prevention and treatment of both OA and sarcopenia.
Sarcopenia/genetics* ; Osteoarthritis/genetics* ; Computational Biology/methods* ; Humans ; Protein Interaction Maps/genetics* ; Animals ; Mice ; Gene Expression Profiling ; Gene Ontology ; Transcriptome ; Male ; Signal Transduction/genetics* ; Gene Regulatory Networks

OBJECTIVES: Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects women's health. This study aims to investigate gene and transcription factor (TF) expression differences between PCOS patients and healthy individuals using bioinformatics approaches, and to verify the function of key transcription factors, with the goal of providing new insights into the pathogenesis of PCOS. METHODS: Differentially expressed genes (DEGs) and differentially expressed transcription factors (DETFs) between PCOS patients and controls were identified from the RNA sequencing dataset GSE168404 using bioinformatics methods. Functional enrichment analysis was performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. The expression and function of core transcription factors were further validated in ovarian tissues of PCOS model mice and control mice using Western blotting and reverse transcription quantitative polymerase chain reaction (RT-qPCR). RESULTS: A total of 332 DEGs were identified between PCOS patients and controls, including 259 upregulated and 73 downregulated genes in the PCOS group. 19 DETFs were further screened, of which 16 were upregulated and 3 were downregulated in PCOS. The upregulated DETFs (including TFCP2L1, DACH1, ESR2, AFF3, SMAD9, ZNF331, HOPX,ATOH8, HIF3α, DPF3, HOXC4, HES1, ID1, JDP2, SOX4, and ID3) were primarily associated with lipid metabolism, development, and cell adhesion. Protein and mRNA expression analysis in PCOS model mice revealed significantly decreased levels of hypoxia-inducible factor (HIF) 1α and HIF2α, and significantly increased expression of HIF3α compared to control mice (all P<0.001). CONCLUSIONS Significant differences in gene and TF expression exist between PCOS patients and healthy individuals. HIF-3α may play a crucial role in PCOS and could serve as a novel biomarker for diagnosis and a potential therapeutic target.
Polycystic Ovary Syndrome/metabolism* ; Female ; Humans ; Animals ; Mice ; Transcription Factors/metabolism* ; Computational Biology ; Gene Expression Profiling ; Adult

OBJECTIVES: Acute lung injury (ALI) is an acute respiratory failure syndrome characterized by impaired gas exchange. Due to the lack of effective targeted drugs, it is associated with high mortality and poor prognosis. Tripterygium wilfordii (TW) has demonstrated anti-inflammatory activity in the treatment of various diseases. This study aims to investigate the effects and underlying mechanisms of TW on myeloid-derived suppressor cells (MDSCs) in ALI, providing experimental evidence for TW as a potential adjuvant therapy for ALI. METHODS: Eighteen specific pathogen-free (SPF) C57BL/6 mice were randomly divided into normal control (NC; intranasal saline), lipopolysaccharide (LPS; 5 mg/kg intranasally to induce ALI), and LPS+TW (50 mg/kg TW by gavage on the first day of modeling, followed by 5 mg/kg LPS intranasally to induce ALI) groups (n=6 each). Lung injury and edema were assessed by histopathological scoring and wet-to-dry weight ratio. Cytokine levels [interleukin (IL)-1β, IL-6, IL-18, tumor necrosis factor-α (TNF-α)] in lung tissue lavage fluid were measured by enzyme-linked immunosorbent assay (ELISA). Flow cytometry was used to assess the proportions of MDSCs, polymorphonuclear MDSCs (PMN-MDSCs), and monocytic MDSCs (M-MDSCs) in bone marrow, spleen, peripheral blood, and lung tissue, as well as reactive oxygen species (ROS) levels in lung tissues. Messenger RNA (mRNA) expression levels of inducible nitric oxide synthase (iNOS) and arginase-1 (ARG-1) in lung tissues were determined by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). PMN-MDSCs sorted from the lungs of LPS-treated mice were co-cultured with splenic CD3⁺ T cells and divided into NC, triptolide (TPL)-L, and TPL-H groups, with bovine serum albumin, 25 nmol/L TPL, and 50 nmol/L TPL, respectively. Flow cytometry was used to detect the effect of PMN-MDSCs on T-cell proliferation, and RT-qPCR was used to measure iNOS and ARG-1 mRNA expression. RESULTS: Compared with the NC group, the LPS group showed marked lung pathology with significantly increased histopathological scores and wet-to-dry ratios (both P<0.001). TW treatment significantly alleviated lung injury and reduced both indices compared with the LPS group (both P<0.05). Cytokine levels were significantly decreased in the LPS+TW group compared with the LPS group (all P<0.001). The proportions of MDSCs in CD45⁺ cells from spleen, bone marrow, peripheral blood, and lung, as well as PMN-MDSCs from spleen, peripheral blood, and lung, were significantly reduced in the LPS+TW group compared with the LPS group (all P<0.05), accompanied by reduced ROS levels in lung tissues (P<0.001). iNOS and ARG-1 mRNA expression in lung tissues was significantly lower in the LPS+TW group than in the LPS group (both P<0.001). In vitro, compared with the TPL-L group, the TPL-H group showed significantly increased CD3⁺ T-cell proliferation (P<0.001), and decreased iNOS and ARG-1 mRNA expression (all P<0.05). CONCLUSIONS TW alleviates the progression of LPS-induced ALI in mice, potentially by reducing the proportion of MDSCs in lung tissues and attenuating the immunosuppressive function of PMN-MDSCs.
Animals ; Acute Lung Injury/chemically induced* ; Myeloid-Derived Suppressor Cells/cytology* ; Tripterygium/chemistry* ; Mice, Inbred C57BL ; Mice ; Cell Differentiation/drug effects* ; Male ; Lipopolysaccharides ; Nitric Oxide Synthase Type II/genetics* ; Cytokines/metabolism* ; Reactive Oxygen Species/metabolism* ; Diterpenes/pharmacology* ; Epoxy Compounds ; Phenanthrenes

OBJECTIVES: Osteoarthritis (OA) is one of the most common chronic degenerative diseases, with chondrocyte apoptosis and extracellular matrix (ECM) degradation as the major pathological changes. The mechanical stimulation can attenuate chondrocyte apoptosis and promote ECM synthesis, but the underlying molecular mechanisms remain unclear. This study aims to investigate the role of primary cilia (PC) in mediating the effects of mechanical stimulation on OA progression. METHODS: In vivo, conditional knockout mice lacking intraflagellar transport 88 (IFT88^flox/flox IFT88 knockout; i.e., primary cilia-deficient mice) were generated, with wild-type mice as controls. OA models were established via anterior cruciate ligament transection combined with destabilization of the medial meniscus, followed by treadmill exercise intervention. OA progression was evaluated by hematoxylin-eosin staining, safranin O-fast green staining, and immunohistochemistry; apoptosis was assessed by TUNEL staining; and limb function by rotarod testing. In vitro, primary articular chondrocytes were isolated from mice and transfected with lentiviral vectors to suppress IFT88 expression, thereby constructing a primary cilia-deficient cell model. Interleukin-1β (IL-1β) was used to induce an inflammatory environment, while cyclic tensile strain (CTS) was applied via a cell stretcher to mimic mechanical loading on chondrocytes. Immunofluorescence and Western blotting were used to detect the protein expression levels of type II collagen α1 chain (COL2A1), primary cilia, IFT88, and caspase-12; reverse transcription polymerase chain reaction was performed to assess COL2A1 mRNA levels; and flow cytometry was used to evaluate apoptosis. RESULTS: In vivo, treadmill exercise significantly reduced Osteoarthritis Research Society International (OARSI) scores and apoptotic cell rates, and improved balance ability in wild-type OA mice, whereas IFT88-deficient OA mice showed no significant improvement. In vitro, CTS inhibited IL-1β-induced ECM degradation and apoptosis in primary chondrocytes; however, this protective effect was abolished in cells with suppressed primary cilia expression. CONCLUSIONS Mechanical stimulation delays OA progression by mediating signal transduction through primary cilia, thereby inhibiting cartilage degeneration and chondrocyte apoptosis.
Animals ; Chondrocytes/cytology* ; Apoptosis/physiology* ; Mice ; Cilia/metabolism* ; Osteoarthritis/pathology* ; Extracellular Matrix/metabolism* ; Mice, Knockout ; Disease Progression ; Interleukin-1beta ; Male ; Cells, Cultured

OBJECTIVES: The neurotoxicity of carbon monoxide (CO) to the central nervous system is a key pathogenesis of delayed encephalopathy after acute carbon monoxide poisoning (DEACMP). Our previous study found that retinoic acid (RA) can suppress the neurotoxic effects of CO. This study further explores, in vivo and in vitro, the molecular mechanisms by which RA alleviates CO-induced central nervous system damage. METHODS: A cytotoxic model was established using the mouse hippocampal neuronal cell line HT22 and primary oligodendrocytes exposed to CO, and a DEACMP animal model was established in adult Kunming mice. Cell viability and apoptosis of hippocampal neurons and oligodendrocytes were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Annexin V/propidium iodide (PI) double staining. The transcriptional and protein expression of each gene was detected using real-time fluorescence quantitative PCR (RT-qPCR) and Western blotting. Long noncoding RNA (lncRNA) SNHG15 and LINGO-1 were knocked down or overexpressed to observe changes in neurons and oligodendrocytes. In DEACMP mice, SNHG15 or LINGO-1 were knocked down to assess changes in central nervous tissue and downstream protein expression. RESULTS: RA at 10 and 20 μmol/L significantly reversed CO-induced apoptosis of hippocampal neurons and oligodendrocytes, downregulation of SNHG15 and LINGO-1, and upregulation of brain-derived neurotrophic factor (BDNF) and tyrosine kinase receptor B (TrkB) (all P<0.05). Overexpression of SNHG15 or LINGO-1 weakened the protective effect of RA against CO-induced cytotoxicity (all P<0.05). Knockdown of SNHG15 or LINGO-1 alleviated CO-induced apoptosis of hippocampal neurons and oligodendrocytes and upregulated BDNF and TrkB expression levels (all P<0.05). Experiments in DEACMP model mice showed that knockdown of SNHG15 or LINGO-1 mitigated central nervous system injury in DEACMP (all P<0.05). CONCLUSIONS RA alleviates CO-induced apoptosis of hippocampal neurons and oligodendrocytes, thereby reducing central nervous system injury and exerting neuroprotective effects. LncRNA SNHG15 and LINGO-1 are key molecules mediating RA-induced inhibition of neuronal apoptosis and are associated with the BDNF/TrkB pathway. These findings provide a theoretical framework for optimizing the clinical treatment of DEACMP and lay an experimental foundation for elucidating its molecular mechanisms.
Animals ; RNA, Long Noncoding/physiology* ; Brain-Derived Neurotrophic Factor/genetics* ; Carbon Monoxide Poisoning/complications* ; Mice ; Tretinoin/pharmacology* ; Nerve Tissue Proteins/metabolism* ; Membrane Proteins/metabolism* ; Apoptosis/drug effects* ; Hippocampus/cytology* ; Receptor, trkB/metabolism* ; Neurons/drug effects* ; Male ; Brain Diseases/etiology* ; Oligodendroglia/drug effects* ; Signal Transduction ; Cell Line

OBJECTIVES: Sepsis-associated acute lung injury (S-ALI) is one of the major causes of death in intensive care unit (ICU) patients, yet its mechanisms remain incompletely understood and effective therapies are lacking. Lytic cell death of macrophages is a key driver of the inflammatory cascade in S-ALI. PANoptosis, a newly recognized form of lytic cell death characterized by PANoptosome assembly and activation, involves plasma membrane rupture (PMR) mediated by ninjurin-1 (NINJ1), a recently identified pore-forming protein. Itaconic acid is known for its anti-inflammatory effects, but its role in macrophage PANoptosis during S-ALI is unclear. This study aims to investigate the protective effect of itaconic acid on macrophage PANoptosis in S-ALI to provide new therapeutic insights. METHODS: Male specific-pathogen-free C57BL/6J mice (6-8 weeks, 18-20 g) received intraperitoneal lipopolysaccharide (LPS) to establish a classical S-ALI model. Western blotting was used to assess PANoptosome-related proteins and enzymes involved in the itaconic acid metabolic pathway, while real-time reverse transcription polymerase chain reaction and metabolomics quantified itaconic acid levels. Primary peritoneal macrophages (PMs) were pretreated with the itaconate derivative 4-octyl itaconate (4-OI) and then exposed to tumor necrosis factor alpha (TNF-α) plus interferon gamma (IFN-γ) to induce PANoptosis. Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. Western blotting was employed to quantify enzymes of the itaconate-metabolic pathway in PANoptotic macrophages, to evaluate the impact of 4-OI on PANoptosome-associated proteins, and to determine NINJ1 abundance in lung tissues from S-ALI mice and in PANoptotic macrophages. Fluorescent dye FM_4-64 was used to visualize 4-OI-mediated changes in PMR, whereas immunofluorescence staining mapped the effect of 4-OI on both the expression level and membrane localization of NINJ1 in PANoptotic macrophages. The effect of 4-OI on lactate dehydrogenase (LDH) release in culture supernatants and peripheal blood serum was assessed using a LDH assay kit, and non-denataring polyacylamide gel electrophoresis was used to assess the expression of NINJ1 in S-ALI mouse lung tissues and the impact of 4-OI on the expression of PANoptosis-associated NINJ1 multimeric reflected protein in macropahges. RESULTS: In S-ALI mouse lungs, PANoptosome components [NOD-like receptor thermal protein domain associated protein 3 (NLRP3), Gasdermin D (GSDMD), Caspase-1, Z-DNA binding protein (ZBP1), and Caspase-3] and phosphorylated mixed lineage kinase domain-like protein (MLKL) S345 were significantly upregulated (all P<0.05), while metabolomics showed compensatory increases in itaconic acid and its key enzymes [aconitate decarboxylase 1 (ACOD1)/immunoresponsive gene 1 (IRG1)]. In macrophages, 4-OI obviously suppressed PANoptosome protein expression, reduced LDH release, restored plasma membrane integrity, and inhibited NINJ1 expression and oligomerization at the membrane (P<0.05). CONCLUSIONS Itaconic acid may alleviate macrophage PANoptosis in S-ALI by inhibiting NINJ1-mediated plasma membrane rupture. Targeting NINJ1 or enhancing itaconate pathways may offer a novel therapeutic strategy for S-ALI.
Animals ; Acute Lung Injury/pathology* ; Succinates/pharmacology* ; Sepsis/complications* ; Mice, Inbred C57BL ; Male ; Mice ; Macrophages/pathology* ; Cell Membrane/metabolism* ; Lipopolysaccharides ; Hydro-Lyases