LPS-induced Cell Model Research Articles

B-lymphocyte-induced maturation protein-1 inhibits inflammation and pyroptosis to alleviate sepsis injury.

Liver and lung tissue damage caused by sepsis is still one of the causes of death. B-lymphocyte-induced maturation protein-1 (Blimp-1) has a protective role in inflammation-related disease. However, whether Blimp-1 can regulate cell pyroptosis and affect disease progression in sepsis is still unclear. Animal and cell models were established by the cecal ligation and puncture method and lipopolysaccharides (LPS)-induced RAW 264.7 cells, respectively, and the role of Blimp-1 in regulation inflammatory response and pyroptosis was verified. The changes of inflammation and pyroptosis in liver and lung tissues of septic mice were determined by the addition of TAK-242 (TLR4 inhibitor). Cell pyroptosis and the level of inflammation was detected after Blimp-1 knockdown and TAK-242 treatment in the cell model. The expression of Blimp-1 was continuously increased in a septic mice model. After treatment with TAK-242, the expression of Blimp-1, pyroptosis and inflammatory levels were reduced in mice. In the LPS-induced cell model, cell injury by knockout Blimp-1 was increased, and cell activity was restored after TAK-242 intervention. Overexpression of Blimp-1 relieved LPS-induced cellular inflammatory damage and pyroptosis. Our study had shown that Blimp-1 could improve septic damage by regulating the level of cellular inflammation and pyroptosis in sepsis.

Catalpol Alleviates Depression by Inhibiting NLRP3 Inflammasome via TLR4/MAPK/NF-Kb Pathway.

We aimed to explore catalpol and NF-k. The role of antidepressant and anti-inflammatory effects of b inhibitor in depression induced by chronic unpredictable mild stress (CUMS). Under the guidance of Qiqihar Medical University, from January 2020 to January 2021, the weight, sucrose consumption and rest time of mice during swimming were monitored, the neurobehavioral changes of rats under CUMS were used to determine the experimental model; ELISA detection of iNOS, ROS, caspase-1, IL-1 β And IL-18 expression level; Western blotting detection of TLR4, MAPK and NF-κB expression level; LPS-induced cell model. INOS, NLRP3, caspase-1, IL-1 in RT-qPCR and ELISA detection models β And IL-18 expression level; the TLR4, MAPK and NF-κB level were detected by Western blotting. CUMS can make rats lose weight, reduce sucrose consumption rate and prolong rest time. Catapol can enhance this effect; In the depression model, ROS, NLRP3, NF-κ B and iNOS were up-regulated Catalpol group MAPK, NF-κ Reduced expression of B and TLR4; ROS, caspase-1, IL-1β, IL-18 and iNOS protein increased. Cell model group TLR4, MAPK and NF-κ. The high protein content of B decreased in catalpol group. Catalpol acts as anti-depressant and anti-inflammatory molecule indepression induced by CUMS. Combination of catalpol with NF-κB inhibitor might play a role in the treatment of depression through regulating the neuroinflammation.

MALAT1-mediated EZH2 Recruitment to the GFER Promoter Region Curbs Normal Hepatocyte Proliferation in Acute Liver Injury.

The goal of this study was to investigate the mechanism by which the long noncoding RNA MALAT1 inhibited hepatocyte proliferation in acute liver injury (ALI). Lipopolysaccharide (LPS) was used to induce an ALI cellular model in HL7702 cells, in which lentivirus vectors containing MALAT1/EZH2/GFER overexpression or knockdown were introduced. A series of experiments were performed to determine their roles in liver injury, oxidative stress injury, and cell biological processes. The interaction of MALAT1 with EZH2 and enrichment of EZH2 and H3K27me3 in the GFER promoter region were identified. Rats were treated with MALAT1 knockdown or GFER overexpression before LPS induction to verify the results derived from the in vitro assay. MALAT1 levels were elevated and GFER levels were reduced in ALI patients and the LPS-induced cell model. MALAT1 knockdown or GFER overexpression suppressed cell apoptosis and oxidative stress injury induced cell proliferation, and reduced ALI. Functionally, MALAT1 interacted directly with EZH2 and increased the enrichment of EZH2 and H3K27me3 in the GFER promoter region to reduce GFER expression. Moreover, MALAT1/EZH2/GFER was activated the AMPK/mTOR signaling pathway. Our study highlighted the inhibitory role of reduced MALAT1 in ALI through the modulation of EZH2-mediated GFER.

FBXO10 prevents chronic unpredictable stress-induced behavioral despair and cognitive impairment through promoting RAGE degradation.

AimsDepression is one of the leading causes of disability worldwide. The receptor for advanced glycosylation end products (RAGE) is closely related to chronic stress and is a target of F‐box protein O10 (FBXO10) which promotes the degradation of RAGE by ubiquitination. Here, we explored the role of FBXO10 and RAGE in chronic unpredictable stress (CUS)‐induced behavioral despair, cognitive impairment, neuroinflammation, and the polarization microglia.MethodsMale C57BL/6 mice with or without infusion of viral in the medial prefrontal cortex (PFC) were subjected to CUS. Then the mice were exposed to forced swim test, sucrose consumption test, novelty‐suppressed feeding test, and temporal object recognition task to assess the behavioral despair and cognitive impairment. Inflammatory cytokines and the neurotrophic factor brain‐derived neurotrophic factor (BDNF) levels in PFC were assessed by enzyme‐linked immunosorbent assay. Immunofluorescence and immunohistochemistry staining were performed to observe the activation and phenotypic transformation of microglia in PFC. LPS‐induced cell model was constructed to explore the effect of FBXO10/RAGE axis in the polarization of microglia in vitro.ResultsFBXO10 promoted RAGE degradation by ubiquitination in BV2 cells. FBXO10 protein levels were reduced whereas RAGE protein levels were enhanced in CUS mice. FBXO10 overexpression or RAGE knockdown inhibited proinflammatory cytokine release, promoted BDNF expression, mitigated the depressive‐like and cognitive impairment behaviors, and affected the polarization of microglia induced by CUS exposure. FBXO10/RAGE axis promoted the polarization of microglia from the M1 to the M2 phenotype in vitro. Moreover, p38 MAPK and NF‐κΒ were identified to be the downstream effect factors for FBXO10/RAGE axis.ConclusionsFBXO10 administration prevents CUS‐induced behavioral despair, cognitive impairment, neuroinflammation, and the polarization of microglia through decreasing the accumulation of RAGE, p38 MAPK, and NF‐κΒ, suggesting potential therapeutic strategies for the prevention and treatment of depression.

Itraconazole Promotes Macrophage M1 Polarization and Phagocytic Capacity of Macrophage to Candida Albicans

Abstract Objective: The present study was designed to evaluate whether and how itraconazole affects the macrophage polarization and its reactivity to Candida albicans. Methods: Cell toxicity of itraconazole was measured using cell counting kit-8 assay in RAW264.7 cells. The cell models were induced by lipopolysaccharide (LPS), interleukin (IL)-4, or Candida albicans. Levels of cytokines secreted by RAW246.7 treated with itraconazole were detected by Luminex or Cytometric Bead Array compared to the controls without itraconazole treatment, and the expressions of inducible nitric oxide synthase and arginase (Arg) were determined by Western blot. Phagocytosis ability was measured by both flow cytometry and fluorescence microscope. The Student's t test and one-way analysis of variance were used to calculate the differences between groups. Results: In comparison to the control, itraconazole inhibited the growth of the cells in both a time- and a dose-dependent manner. Increased secretion of IL-6 (0.25 μmol/L ITZ [538.03 ± 60.23 pg/mL, P < 0.05], 0.5 μmol/L [550.32 ± 47.87 pg/mL, P < 0.05] and 1 μmol/L [626.95 ± 75.24 pg/mL, P < 0.01] vs. control [370.43 ± 33.98 pg/mL]) and tumor necrosis factor-alpha (TNF-α) (1 μmol/L ITZ vs. control: 2521.51 ± 444.06 pg/mL vs. 1617.85 ± 94.57 pg/mL, P < 0.05) were detected in the LPS-induced cell model with itraconazole treatment. In the cells induced by IL-4, itraconazole increased the secretion of IL-6 (1 μmol/L ITZ vs. control: 528.33 ± 11.60 pg/mL vs. 466.99 ± 28.32 pg/mL, P < 0.05), TNF-α (1 μmol/L ITZ vs. control: 4.85 ± 0.32 pg/mL vs. 4.30 ± 0.19 pg/mL, P < 0.05), and IL-1β (0.25 μmol/L [325.95 ± 13.97 pg/mL, P < 0.05], 0.5 μmol/L [332.38 ± 11.97 pg/mL, P < 0.05] and 1 μmol/L [334.35 ± 16.23 pg/mL, P < 0.05] vs. control [291.62 ± 17.03 pg/mL]), and reduced the secretion of IL-10 (1 μmol/L ITZ vs. control: 7.21 ± 0.68 pg/mL vs. 9.11 ± 0.14 pg/mL, P < 0.05). The secretion of IL-6 (1 μmol/L ITZ vs. control: 38.34 ± 1.36 pg/mL vs. 32.32 ± 0.84 pg/mL, P < 0.05) and TNF-α (1 μmol/L ITZ vs. control: 1060.17 ± 80.16 pg/mL vs. 890.84 ± 52.82 pg/mL, P < 0.01) was improved in Candida albicans-stimulated RAW264.7 cells under the treatment of itraconazole, while the secretion of IL-4 (0.5 μmol/L [2.86 ± 0.20 pg/mL, P < 0.05] and 1 μmol/L [2.24 ± 0.33 pg/mL, P < 0.001] vs. control [3.91 ± 0.23 pg/mL]) and IL-10 (1 μmol/L ITZ vs. control: 19.46 ± 2.05 pg/mL vs. 25.67 ± 1.95pg/mL, P < 0.05) decreased. In all three activated patterns, itraconazole enhanced the expression of inducible nitric oxide synthase (P < 0.01) and slightly inhibited the Arg-1 expression (P < 0.05). Phagocytosis ability of RAW264.7 cells at 1 μmol/L ITZ treatment was increased by 7.53% ± 2.21% (P < 0.01) and 9.73% ± 2.03% (P < 0.01) at the ratio of cells: yeast of 1:4 and 1:8, respectively, in comparison to the control group. Conclusion: Itraconazole improved M1 polarization of RAW264.7 cells and enhanced the phagocytic capacity of RAW264.7 to Candida albicans, indicating a significant immunological enhancement. The study improves the understanding of undergoing mechanisms related to the anti-tumor and anti-infection effects of itraconazole.