Inflammatory Response In RAW264 Research Articles

Inhibition of LPS-induced inflammatory response in RAW264.7 cells by natural Chlorogenic acid isomers involved with AKR1B1 inhibition

Inflammation is the physiological response of the immune system to injury or infection, typically manifested by local tissue congestion, swelling, heat, and pain. Prolonged or excessive inflammation can lead to tissue damage and the development of many diseases. The anti-inflammatory effects of natural ingredients have been extensively researched and confirmed. This study investigated the effects of Chlorogenic acid (CGA) isomers —— 3-Caffeolyquninic acid (3-CQA), 4-Caffeolyquninic acid (4-CQA), and 5-Caffeolyquninic acid (5-CQA) —— on the inflammatory response and oxidative stress reaction induced by LPS in RAW264.7 cells. Overall, 3-CQA exhibited the most significant reduction in levels of TNF-α, IL-6, NO, and ROS. 4-CQA showed superior inhibition of TNF-α compared to 5-CQA (p < 0.05), while no significant difference in other parameters. We further used DARTS and CETSA to demonstrate that CGA isomers have stable affinity with AKR1B1. As a positive control, the AKR1B1 antagonist epalrestat exhibited similar effects to the CGA isomers. 3-CQA having the smallest half-inhibitory concentration (IC50) for AKR1B1, while 4-CQA and 5-CQA have similar values. AutoDock simulations of the docking conformations revealed minimal differences in the average binding energies of the CGA isomers. The main differences were that VAL47 formed a hydrogen bond with 3-CQA, whereas GLN49 formed hydrogen bonds with 4-CQA and 5-CQA. Additionally, the number of hydrophobic bonds involving PHE122 and LEU300 varies. Our conclusion is that differences in non-covalent interactions result in the varying inhibitory abilities of CGA isomers on AKR1B1, which further affect the anti-inflammatory and antioxidant effects of CGA isomers.

QSOX1 exerts anti-inflammatory effects in sepsis-induced acute lung injury: Regulation involving EGFR phosphorylation mediated M1 polarization of macrophages

Sepsis is a systemic inflammatory response caused by an infection, which can easily lead to acute lung injury. Quiescin Q6 sulfhydryl oxidase 1 (QSOX1) is a sulfhydryl oxidase involved in oxidative stress and the inflammatory response. However, there are few reports on the role of QSOX1 in sepsis-induced acute lung injury (SALI). In this study, mice model of SALI was constructed by intraperitoneal injection with lipopolysaccharide (LPS). The increased inflammatory response and lactate dehydrogenase activity in bronchoalveolar lavage fluid (BALF) indicated successful modeling. Increased QSOX1 expression was both observed in lung tissues and lung macrophages of sepsis mice accompanied by increased polarization of M1-type macrophages. To explore the role of QSOX1 in the SALI, lentivirus containing QSOX1-specific overexpression or knockdown vectors were used to change QSOX1 expression in LPS-treated RAW264.7 cells. QSOX1 suppressed LPS-induced M1 polarization and further inhibited inflammatory response in RAW264.7 cells. Interestingly, the phosphorylation of epidermal growth factor receptor (EGFR), the promoter of M1 polarization in macrophages, was found to be downregulated upon QSOX1 overexpression in RAW264.7 cells. Mechanically, the binding of QSOX1 to EGFR protein promoted EGFR ubiquitination and degradation, thereby down-regulating EGFR phosphorylation. Moreover, inhibiting EGFR expression or its phosphorylation restored the impact of QSOX1 silencing on M1 polarization and inflammation in the LPS-treated RAW264.7 cells. In summary, QSOX1 may exert anti-inflammatory effects in SALI by inhibiting EGFR phosphorylation-mediated M1 macrophage polarization. This presented a potential target for the treatment and prevention of SALI.

Nobiletin Regulates Polyinosinic-polycytidylic Acid-induced Inflammation in Macrophages Partially via the PPAR-γ Signaling Pathway.

Macrophage dysregulation is a common pathogenic feature of viruses that provides extensive targets for antiviral therapy. Nobiletin, a polymethoxylated flavonoid found in citrus fruits, has a multitude of effects. We investigated the effect of nobiletin on polyinosinic-polycytidylic acid (poly(I:C))-induced inflammation in RAW264.7 cells. Nobiletin inhibited the production of poly(I:C)-induced inflammatory factors, including tumor necrosis factor (TNF)-α, interleukin (IL)-6, and CXCL10. High-throughput sequencing revealed that nobiletin inhibited the expression of TNF-α, IL-6, and CXCL10 and promoted the expression of CD206, Chil3, and Vcam1. In the Kyoto Encyclopedia of Genes and Genomes enrichment analyses, the upregulated differential genes were significantly enriched in the peroxisome proliferator-activated receptor (PPAR) signaling pathway. The PPAR-γ inhibitor T0070907 significantly reversed the inhibitory effects of nobiletin on IL-6 and CXCL10 but had no significant effect on TNF-α secretion. Thus, nobiletin regulated poly(I:C)-induced inflammatory responses in RAW264.7 cells partially via the PPAR-γ signaling pathway.

Chloroquine regulates the lipopolysaccharide-induced inflammatory response in RAW264.7 cells.

Macrophage-induced inflammation plays a key role in defense against injury and harmful pathogens. Autophagy and the inflammatory response are associated; however, the relationship between the autophagy pathway and lipopolysaccharide (LPS)- induced inflammatory responses remains unknown. We aimed to determine the effect of autophagy on the LPS-induced myeloid differentiation factor 88 (MyD88)/nuclear transcription factor kB (NF-kB) pathway-mediated inflammatory response in RAW264.7 cells. To determine the effect of autophagy on the LPS-induced inflammatory response, using various in vitro assays, we determined the effect of autophagy inhibitors and inducers on the inflammatory response in RAW264.7 cells. Chloroquine (CQ), an autophagy inhibitor, suppressed pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNFα) in LPS-stimulated RAW264.7 cells. CQ also affected inflammatory mediators such as myeloid differentiation factor 88 and NF-kB in LPS-stimulated RAW264.7 cells. This study demonstrated that CQ regulates the LPS-induced inflammatory response in RAW264.7 cells. We propose that targeting the regulation of pro-inflammatory cytokine levels and inflammatory mediators using CQ is a promising therapeutic approach for preventing inflammatory injury. CQ serves as a potential therapeutic target for treating various inflammatory diseases.

Purine-rich Element-binding Protein B Mediates Ferroptosis in Lipopolysaccharide-induced Raw264.7 Macrophage Inflammation.

Lipopolysaccharide (LPS) plays an important role in Raw264.7 macrophage ferroptosis and inflammation. Purine-rich element-binding protein B (Purb) influences cellular processes by regulating gene expression as a transcription factor. However, the effect and molecular mechanism of Purb in regulating Raw264.7 macrophage ferroptosis is still unknown. In this study, we used malondialdehyde, glutathione (GSH) assays, Fe 2+ fluorescence, reactive oxygen species staining, and western blotting to determine the effect of Purb on LPS-induced Raw264.7 macrophage ferroptosis. Pharmacological inhibitor of ferroptosis was utilized to explore its potential effects for inflammation by reverse transcription-quantitative polymerase chain reaction analysis. Meanwhile, chromatin immunoprecipitation was performed to verify the binding of Purb and the GSH-dependent peroxidase 4 (Gpx4). The results showed that LPS-induced inflammation in Raw264.7 macrophages was inhibited by ferroptosis inhibitor Fer-1 treatment. LPS inhibited the expression of Purb in Raw264.7 macrophages. In addition, Purb overexpression relieved the ferroptosis, and inflammatory response of Raw264.7 macrophages induced by LPS. Mechanistically, the binding of Purb to the Gpx4 promoter was decreased after LPS stimulation. Therefore, we concluded for the first time that Purb played a critical role in LPS-induced ferroptosis and inflammatory response by regulating the transcription of Gpx4. These results provide a theoretical basis for further research on the macrophage ferroptosis and inflammation.

Type I Cystatin Derived from Cysticercus pisiformis-Stefins, Suppresses LPS-Mediated Inflammatory Response in RAW264.7 Cells.

Cysticercus pisiformis is a kind of tapeworm larvae of Taenia pisiformis, which parasitizes the liver envelope, omentum, mesentery, and rectum of rodents such as rabbits. Cysteine protease inhibitors derived from helminth were immunoregulatory molecules of intermediate hosts and had an immunomodulatory function that regulates the production of inflammatory factors. Thus, in the present research, the recombinant Stefin of C. pisiformis was confirmed to have the potential to fight inflammation in LPS-Mediated RAW264.7 murine macrophages. CCK8 test showed that rCpStefin below 50 μg/mL concentration did not affect cellular viability. Moreover, the NO production level determined by the Griess test was decreased. In addition, the secretion levels of IL-1β, IL-6, and TNF-α as measured by ELISA were decreased. Furthermore, it exerted anti-inflammatory activity by decreasing the production of proinflammatory cytokines and proinflammatory mediators, including IL-1β, IL-6, TNF-α, iNOS, and COX-2 at the gene transcription level, as measured by qRT-PCR. Therefore, Type I cystatin derived from C. pisiformis suppresses the LPS-Mediated inflammatory response of the intermediate host and is a potential candidate for the treatment of inflammatory diseases.

Exploring the chemical diversity of sesquiterpenes from the rarely studied south China sea soft coral Sinularia tumulosa assisted by molecular networking strategy

Molecular networking strategy-based prioritization of the isolation of the rarely studied soft coral Sinularia tumulosa yielded 14 sesquiterpenes. These isolated constituents consisted of nine different types of carbon frameworks, namely asteriscane, humulane, capillosane, seco-asteriscane, guaiane, dumortane, cadinane, farnesane, and benzofarnesane. Among them, situmulosaols A–C (1, 3 and 4) were previously undescribed ones, whose structures with absolute configurations were established by the combination of extensive spectral data analyses, quantum mechanical-nuclear magnetic resonance and time-dependent density functional theory electronic circular dichroism calculations, the Snatzke's method, and the modified Mosher's method. Notably, situmulosaol C (4) was the second member of capillosane-type sesquiterpenes. The plausible biogenetic relationships of these skeletally different sesquiterpenes were proposed. All sesquiterpenoids were evaluated for their antibacterial, cytotoxic and anti-inflammatory effects. The bioassay results showed compound 14 exhibited significant antibacterial activities against a variety of fish and human pathogenic bacteria with MIC90 values ranging from 3.6 to 33.8 μg/mL. Moreover, moderate cytotoxic effects against HEL cells for components 13 and 14 and moderate inhibitory effect on lipopolysaccharide-induced inflammatory responses in RAW264.7 cells for substance 13 were also observed.

A potential virulence factor: Brucella flagellin FliK does not affect the main biological properties but inhibits the inflammatory response in RAW264.7 cells

The bacterial flagellum is an elongated filament that protrudes from the cell and is responsible for bacterial motility. It can also be a pathogen-associated molecular pattern (PAMP) that regulates the host immune response and is involved in bacterial pathogenicity. In contrast to motile bacteria, the Brucella flagellum does not serve a motile purpose. Instead, it plays a role in regulating Brucella virulence and the host‘s immune response, similar to other non-motile bacteria. The flagellin protein, FliK, plays a key role in assembly of the flagellum and also as a potential virulence factor involved in the regulation of bacterial virulence and pathogenicity. In this study, we generated a Brucella suis S2 flik gene deletion strain and its complemented strain and found that deletion of the flik gene has no significant effect on the main biological properties of Brucella, but significantly enhanced the inflammatory response induced by Brucella infection of RAW264.7 macrophages. Further experiments demonstrated that the FliK protein was able to inhibit LPS-induced cellular inflammatory responses by down-regulating the expression of MyD88 and NF-κB, and by decreasing p65 phosphorylation in the NF-κB pathway; it also inhibited the expression of NLRP3 and caspase-1 in the NLRP3 inflammasome pathway. In conclusion, our study suggests that Brucella FliK may act as a virulence factor involved in the regulation of Brucella pathogenicity and modulation of the host immune response.

Silkworm pupa protein-derived peptides alleviate LPS-induced inflammatory response in RAW264.7 macrophage cells through the NF-κB/MAPK/PI3K-AKT signaling pathway

A plethora of studies have indicated that protein or peptides derived from food sources possess potential anti-inflammatory activity. In our previous research, we discovered peptides from silkworm pupae (Bombyx mori) exhibited promising anti-inflammatory effects in mice. However, the anti-inflammatory activity of silkworm pupae protein peptides (SPP) has yet to be validated at the cellular level, and its underlying anti-inflammatory mechanisms remain unclear. Therefore, the aim of this study was to explore the anti-inflammatory potential of SPP in lipopolysaccharide (LPS)-induced RAW264.7 inflammation model. Our research findings demonstrated that SPP significantly reduced LPS-induced inflammation in RAW264.7 cells in a dose-dependent manner, including decreased levels of inflammatory mediators (NO, MCP-1, and PEG2) and cytokines (TNF-α, IL-6, and IL-1β). Furthermore, we observed significant downregulation of mRNA and protein expression of iNOS and COX-2 by SPP (p < 0.05). Additionally, SPP exerted its anti-inflammatory effects by inhibiting the NF-κB/MAPK/PI3K signaling pathway. These results suggested that SPP may serve as a novel functional food ingredient for the prevention or treatment of inflammation-related diseases.

Microarray analysis of tRNA-derived small RNA (tsRNA) in LPS-challenged macrophages treated with metformin

Metformin, a widely used anti-diabetic drug, has demonstrated its efficacy in addressing various inflammatory conditions. tRNA-derived small RNA (tsRNA), a novel type of small non-coding RNA, exhibits diverse regulatory functions and holds promise as both a diagnostic biomarker and a therapeutic target for various diseases. The purpose of this study is to investigate whether the abundance of tsRNAs changed in LPS versus LPS + metformin-treated cells, utilizing microarray technology. Firstly, we established an in vitro lipopolysaccharide (LPS)-induced inflammation model using RAW264.7 macrophages and assessed the protective effects of metformin against inflammatory damage. Subsequently, we extracted total RNA from both LPS-treated and metformin + LPS-treated cell samples for microarray analysis to identify differentially abundant tsRNAs (DA-tsRNAs). Furthermore, we conducted bioinformatics analysis to predict target genes for validated DA-tsRNAs and explore the biological functions and signaling pathways associated with DA-tsRNAs. Notably, metformin was found to inhibit the inflammatory response in RAW264.7 macrophages. The microarray results revealed a total of 247 DA-tsRNAs, with 58 upregulated and 189 downregulated tsRNAs in the Met + LPS group compared to the LPS group. The tsRNA-mRNA network was visualized, shedding light on potential interactions. The results of bioinformatics analysis suggested that these potential targets of specific tsRNAs were mainly related to inflammation and immunity. Our study provides compelling evidence that metformin exerts anti-inflammatory effects and modulates the abundance of tsRNAs in LPS-treated RAW264.7 macrophages. These findings establish a valuable foundation for using tsRNAs as potential biomarkers for metformin in the treatment of inflammatory conditions.

Isolation and anti‐inflammatory evaluation of diterpene lactones from Andrographis paniculata collected in Bac Giang province, Vietnam

AbstractPhytochemical components of the aerial parts of Andrographis paniculata collected in Bac Giang province was investigated. Fourteen compounds, including seven labdane diterpene lactones [andrographolide (1), 3,19‐isopropylidene‐andrographolide (2), andropanolide (4), 14‐deoxy‐12‐hydroxyandrographolide (5), 14‐dehydroxyandrographolide‐12‐sulfonic acid (6), 14‐deoxy‐11,12‐didehydroandrographolide (8), 14‐deoxy‐14,15‐didehydroandrographolide (11)], together with four diterpene glycosides [andrographiside (3), neoandrographolide (7), andropanoside (9), 14‐deoxy‐11,12‐didehydroandrographiside (10)], and three iridoid glycosides [harpagide (12), 6‐epi‐8‐O‐acetyl‐harpagide (13), procumbide (14)] were isolated. Among these, 14‐dehydroxyandrographolide‐12‐sulfonic acid (6) was isolated for the first time from natural resource, and for the first‐time harpagide (12) was isolated from Andrographis paniculata species. The detailed structures of isolated compounds were elucidated by analyses of 1D and 2D NMR spectra and compared to the published data. Diterpene lactones, 1–2, 5 and 10–11, were evaluated for their anti‐inflammatory inhibition on LPS‐triggered inflammatory responses in RAW 264.7 cells, in which 1 and 2 showed significantly potent inhibition on NO production with IC50 values of 1.3 and 0.34 µm, respectively.

Sasanquasaponin from Camellia oleifera Abel Exerts an Anti-Inflammatory Effect in RAW 264.7 Cells via Inhibition of the NF-κB/MAPK Signaling Pathways.

Sasanquasaponin (SQS), a secondary metabolite that is derived from Camellia seeds, reportedly possesses notable biological properties. However, the anti-inflammatory effects of SQS and its underlying mechanisms remain poorly explored. Herein, we aimed to investigate the anti-inflammatory properties of SQS against lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 cells, focusing on the nuclear factor-κB (NF-κB) and MAPK signaling pathways. SQS was isolated using a deep eutectic solvent and D101 macroporous adsorption resin and analyzed using high-performance liquid chromatography. The viability of LPS-stimulated RAW264.7 was assessed using the CCK-8 assay. The presence of reactive oxygen species (ROS) was evaluated using 2',7'-dichlorofluorescein-diacetate. The expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) were detected using reverse transcription-quantitative PCR and ELISA. Western blot was performed to analyze the protein expression of LPS-induced RAW264.7 cells. Herein, SQS exhibited anti-inflammatory activity: 30 μg/mL of SQS significantly reduced ROS generation, inhibited the LPS-induced expression of iNOS and COX-2, and attenuated the production of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α. The anti-inflammatory activity was potentially mediated by inhibiting the phosphorylation of IκBα and p65 in the NF-κB signaling pathway and the phosphorylation of ERK and JNK in the MAPK signaling pathway. Accordingly, SQS could inhibit inflammation in LPS-induced RAW264.7 cells by suppressing the NF-κB and MAPK signaling pathways. This study demonstrated the potential application of SQS as an anti-inflammatory agent.

Development of new dehydrocostuslactone derivatives for treatment of atopic dermatitis via inhibition of the NF-κB signaling pathway.

Atopic dermatitis (AD), a recurrent inflammatory systemic skin disease, is difficult to cure. In the present study, several ethylenediamine-derived dehydrocostuslactone (DHCL) derivatives were prepared to assess their in vitro and in vivo anti-inflammatory activities. The results indicated that DHCL derivatives inhibited NO generation with low cytotoxicity. In particular, compound 5d exhibited the best anti-inflammatory activity. Subsequent experiments revealed that 5d not only inhibited the LPS-induced inflammatory response in RAW264.7 cells via the MAPK-NF-κB signaling pathway inhibition but also significantly decreased Th2-type cytokine levels and inhibited the NF-κB signaling pathway activation in mice with MC903-induced AD. Therefore, DHCL derivatives may be considered as new agents for the treatment of AD.

Six Undescribed Capnosane-Type Macrocyclic Diterpenoids from South China Sea Soft Coral Sarcophyton crassocaule: Structural Determination and Biological Evaluation.

Six undescribed capnosane-type macrocyclic diterpenes sarcocrassolins A-F (1-6) and one related known analog pavidolide D (7) were isolated from Sarcophyton crassocaule, a soft coral collected off the Nansha Islands, in the South China Sea. Their complete structures, relative configurations and absolute configurations were established through comprehensive spectroscopic analysis, quantum mechanical nuclear magnetic resonance (QM-NMR) and single-crystal X-ray diffraction. Sarcocrassolins D (4) and E (5) showed inhibitory activity against lipopolysaccharide (LPS)-stimulated inflammatory responses in RAW264.7 cells with IC50 values of 76.8 ± 8.0 μM and 93.0 ± 3.8 μM, respectively.

In vitro anti-inflammatory and comparative cytotoxicity studies on methanolic extract of Enicostemma hyssopifolium

Enicostemma hyssopifolium is a perineal herb widely used as an antidiabetic agent in folklore medicine. The present work was focused on the assessment of its anti-inflammatory and cytotoxic properties. Its methanolic extract was evaluated for anti-inflammatory activity using murine monocytic macrophage RAW 264.7 cells, and screened for its cytotoxic property in different cancer cell lines. The methanolic extract was able to potentially inhibit the bacterial lipopolysaccharides-induced inflammatory response in RAW 264.7 cells. Results of the cytotoxicity studies revealed that the methanolic extract effectively induced the cytotoxicity at considerably lower concentration in MCF-7, A-549, and COLO-205 cell lines, while the viability of HeLa, CasKi, and HT-29 cells were inhibited at comparatively higher concentrations. Results thus indicated that E. hyssopifolium possessed potent anti-inflammatory and cytotoxic properties. This necessitates further exploration of bioactive phytochemical compounds responsible for these properties for therapeutic applications.

Citri Reticulatae Pericarpium Limits TLR-4-Triggered Inflammatory Response in Raw264.7 Macrophages by Activating RasGRP3.

Inflammation is an important immune response to pathogen invasion, but excessive inflammation leads to tissue injury and even cytokine storm. Therefore, proper response is needed depending on the intensity of the infection. Ras guanine nucleotide releasing protein 3 (RasGRP3) is a regulator of the TLR-mediated response. In low-intensity inflammation, it negatively regulates production of pro-inflammatory cytokines, especially IL-6. Citri Reticulatae Pericarpium, the peel of Citrus reticulata Blanco, is a major medicinal herb in Korean medicine. The present study aims to investigate whether the Citri Reticulatae Pericarpium extract (CRE) has immunomodulatory activity using the Raw264.7 macrophage. Also, we investigated the effect of CRE on RasGRP3 expression. In the present study, CRE reduced IL-6 production in the low-LPS environment (1 ng/mL) and did not in the high-LPS environment (100 ng/mL). The suppression of IL-6 production in the low-LPS environment (1 ng/mL) was abolished after the pretreatment of RasGRP3 siRNA. The reduced RasGRP3 protein content by 100 ng/mL LPS treatment was increased by CRE treatment. Additionally, nobiletin, a major component of CRE showed a suppressive effect on IL-6 production in the low-LPS environment (1 ng/mL). The present results suggest that CRE alleviates inflammatory response via activating RasGRP3 expression in low-intensity inflammation.

Genomic DNA Extracted from Lactiplantibacillus plantarum Attenuates Porphyromonas gingivalis Lipopolysaccharide (LPS)-Induced Inflammatory Responses via Suppression of Toll-Like Receptor (TLR)-Mediated Mitogen-Activated Protein Kinase (MAPK) and Nuclear Factor-κB (NF-κB) Signaling Pathways.

In the present study, we aimed to examine the inhibition of genomic DNA from Lactiplantibacillus plantarum (LpDNA) on Porphyromonas gingivalis lipopolysaccharide (PgLPS)-induced inflammatory responses in RAW264.7 cells. Pretreatment with LpDNA for 15 h significantly inhibited PgLPS-induced mRNA expression and protein secretion of interleukin (IL)-1β, IL-6, and monocyte chemoattractant protein-1. LpDNA pretreatment also reduced the mRNA expression of Toll-like receptor (TLR)2 and TLR4. Furthermore, LpDNA inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) and the activation of nuclear factor-κB (NF-κB) induced by PgLPS. Taken together, these findings demonstrate that LpDNA attenuates PgLPS-induced inflammatory responses by regulating MAPKs and NF-κB signaling pathways through the suppression of TLR2 and TLR4 expression.

Aspirin eugenol ester ameliorates LPS-induced inflammatory responses in RAW264.7 cells and mice.

Introduction: Inflammation is a defensive response of the body and the pathological basis of many diseases. However, excessive inflammation and chronic inflammation impair the homeostasis of the organism. Arachidonic acid (AA) has a close relationship with inflammation and is the main mediator of the pro-inflammatory response. Based on the prodrug principle, the new pharmaceutical compound aspirin eugenol ester (AEE) was designed and synthesized. However, the effects of AEE on key enzymes, metabolites and inflammatory signaling pathways in the AA metabolic network have not been reported. Methods: In this study, the anti-inflammation effects of AEE were first investigated in mice and RAW264.7 cells in LPS induced inflammation model. Then, the changes of the key enzymes and AA metabolites were explored by RT-PCR and targeted metabolomics. Moreover, the regulatory effects on NF-kB and MAPKS signaling pathways were explored by Western Blotting. Results: Results indicated that AEE significantly reduced the number of leukocyte and increased the lymphocyte percentage. AEE decreased the expression levels of IL-1β, IL-6, IL-8 and TNF-α both in vivo and in vitro. In the liver of mice, AEE downregulated the levels of AA, prostaglandin D2 (PGD2) and upregulated 12- hydroxyeicosatetraenoic acid (12-HETE). However, the changes of PGE2, PGF2α, 6-keto-prostaglandin F1α (6-KETO-PGF1α), 9-hydroxy-octadecenoic acid (9- HODE), 13-HODE, 15-HETE, docosahexaenoic acid (DHA) and thromboxane B2 (TXB2) were not significant. Additionally, it was found that AEE decreased the relative mRNA expression levels of p65 and p38 and the ratio of p-p65/p65. Discussion: It was concluded that AEE might inhibit the LPS-induced inflammatory response through the regulation of AA metabolism. This study provides the theoretical foundation for the development of AEE as a medicinal anti-inflammatory drug.

Exosomal PPARγ derived from macrophages suppresses LPS-induced peritonitis by negative regulation of CD14/TLR4 axis.

Intercellular communication between macrophages and peritoneal mesothelial cells (PMCs) has been suggested as a key factor regulating peritonitis development. Here, we explored whether PPARγ (peroxisome proliferator-activated receptor gamma) can be packaged into macrophage exosomes to mediate intercellular communication and regulate peritonitis. Macrophage exosomes were isolated by ultracentrifugation and identified by nanoparticle tracking analysis and transmission electron microscopy. Proteomic analysis of macrophage-derived exosomes was performed using mass spectrometry. Co-culture models of supernatants or exosomes with PMCs, as well as a mouse peritonitis model induced by lipopolysaccharide (LPS), were employed. In this study, using stable Raw264.7 cells overexpressing GFP-FLAG-PPARγ (OE-PPARγ), we found that PPARγ inhibited LPS-induced inflammatory responses in Raw264.7 cells and that PPARγ was incorporated into macrophage exosomes during this process. Overexpression of PPARγ mainly regulated thesecretion ofdifferentiallyexpressed exosomal proteins involved in the biological processes of protein transport, lipid metabolic process, cell cycle, apoptotic process, DNA damage stimulus, as well as the KEGG pathway of salmonella infection. Using co-culture models and mouse peritonitis model, we showed that exosomes from Raw264.7 cells overexpressing PPARγ inhibited LPS-induced inflammation in co-cultured human PMCs and in mice through downregulating CD14 and TLR4, two key regulators of the salmonella infection pathway. Pretreatment of the PPARγ inhibitor GW9662 abolished the anti-inflammatory effect of exosomes from Raw264.7 OE-PPARγ cells on human PMCs. These results suggested that overexpression of PPARγ largely altered the proteomic profile of macrophage exosomes and that exosomal PPARγ from macrophages acted as a regulator of intercellular communication to suppress LPS-induced inflammatory responses in vitro and in vivo via negatively regulating the CD14/TLR4 axis.

Bojungikgi-tang Alleviates Lipopolysaccharide-Induced Inflammatory Responses in RAW264.7 Macrophages and C57BL/6 Mice

Bojungikgi-tang Alleviates Lipopolysaccharide-Induced Inflammatory Responses in RAW264.7 Macrophages and C57BL/6 Mice