Inhibition Of Interleukin-6 Production Research Articles

Structure-Activity Relationship Analysis of Fluoxetine for Suppression of Inflammatory Cytokine Production.

There is accumulating evidence that selective serotonin reuptake inhibitors (SSRIs), clinically used as antidepressants, have a beneficial effect on inflammatory diseases such as coronavirus disease 2019 (COVID-19). We previously compared the inhibitory effects of five U.S. Food and Drug Administration (FDA)-approved SSRIs on the production of an inflammatory cytokine, interleukin-6 (IL-6), and concluded that fluoxetine (FLX) showed the most potent anti-inflammatory activity. Here, we investigated the structure-activity relationship of FLX for anti-inflammatory activity towards J774.1 murine macrophages. FLX suppressed IL-6 production induced by the TLR3 agonist polyinosinic-polycytidylic acid (poly(I : C)) with an IC50 of 4.76 µM. A derivative of FLX containing chlorine instead of the methylamino group lacked activity, suggesting that the methylamino group is important for the anti-inflammatory activity. FLX derivatives bearing an N-propyl or N-(pyridin-3-yl)methyl group in place of the N-methyl group exhibited almost the same activity as FLX. Other derivatives showed weaker activity, and the N-phenyl and N-(4-trifluoromethyl)benzyl derivatives were inactive. The chlorine-containing derivative also lacked inhibitory activity against TLR9- or TLR4-mediated IL-6 production. These derivatives showed similar structure-activity relationships for TLR3- and TLR9-mediated inflammatory responses. However, the activities of all amino group-containing derivatives against the TLR4-mediated inflammatory response were equal to or higher than the activity of FLX. These results indicate that the substituent at the nitrogen atom in FLX strongly influences the anti-inflammatory effect.

Induction of Lipopolysaccharide During Pregnancy Will Suppress IL-6 Production but not Activin B

Purpose: The purpose of this study was to investigate the response of interleukin-6 (IL-6) and activin B in pregnant mice following induction with lipopolysaccharide (LPS). Given the known role of proinflammatory cytokines such as IL-6 and activin B in inflammation, and the potential modulation of their production by estradiol, which is elevated during pregnancy, this research aimed to understand the impact of pregnancy on the inflammatory response in mice. Methods: The study involved two groups of mice: one group consisted of 8 non-pregnant mice, while the other comprised 13 pregnant mice in the second week of gestation. Inflammation was induced in the mice through intraperitoneal injection of LPS from Escherichia coli serotype O111:B4. After 4 hours of treatment, serum samples were collected from the mice's intracardiac blood to measure levels of estradiol, IL-6, and activin B using enzyme-linked immunosorbent assay (ELISA). Results and Discussion: The results showed that pregnancy significantly reduced IL-6 levels (P=0.015), indicating a suppression of proinflammatory cytokine production during gestation. However, there was no significant difference in estradiol (P=0.169) and activin B (P=0.583) levels between pregnant and non-pregnant mice following LPS induction. Additionally, no significant association was found between estradiol and IL-6 (P=0.637) or activin B (P=0.306). These findings suggest that while pregnancy influences the inflammatory response, particularly affecting IL-6 levels, it may not directly modulate estradiol and activin B production in the context of acute inflammation induced by LPS. Implications of the Research: The observed reduction in IL-6 levels during pregnancy following LPS induction highlights the complex interplay between pregnancy and the immune system. Understanding how pregnancy influences inflammatory responses can have implications for managing inflammatory conditions in pregnant individuals and developing targeted interventions to mitigate potential risks associated with altered immune function during gestation. Originality/Value: This research contributes to the existing knowledge by elucidating the specific effects of pregnancy on the production of IL-6 and activin B in response to inflammatory stimuli. By focusing on a murine model and employing ELISA to quantify cytokine levels, this study provides valuable insights into the immunomodulatory effects of pregnancy, shedding light on the mechanisms underlying altered inflammatory responses during gestation.

Synthesis of secretory leukocyte protease inhibitor using cell-free protein synthesis system.

Secretory leukocyte protease inhibitor (SLPI) functions as a protease inhibitor that modulates excessive proteolysis in the body, exhibits broad-spectrum antimicrobial activity, regulates inflammatory responses, and plays an important role in the innate immunity. The purpose of the study was to artificially synthesize a SLPI, an antimicrobial peptide, and investigate its effect on antimicrobial activity against Porphyromonas gingivalis and interleukin-6 (IL-6) production. SLPI protein with a molecular weight of approximately 13kDa was artificially synthesized using a cell-free protein synthesis (CFPS) system and investigated by western blotting and enzyme-linked immunosorbent assay (ELISA). Disulfide bond isomerase in the protein synthesis mixture increased the amount of SLPI synthesized. The synthesized SLPI (sSLPI) protein was purified and its antimicrobial activity was investigated based on the growth of Porphyromonas gingivalis and bacterial adhesion to oral epithelial cells. The effect of sSLPI on IL-6 production in human periodontal ligament fibroblasts (HPLFs) was examined by ELISA. Our results showed that sSLPI significantly inhibited the growth of Porphyromonas gingivalis and bacterial adhesion to oral epithelial cells and further inhibited IL-6 production by HPLFs. These results suggested that SLPI artificially synthesized using the CFPS system may play a role in the prevention of periodontal diseases through its antimicrobial and anti-inflammatory effects.

Naphthoquinone derivatives as potential immunomodulators: prospective for COVID-19 treatment.

Inflammation plays a crucial role in COVID-19, and when it becomes dysregulated, it can lead to severe outcomes, including death. Naphthoquinones, a class of cyclic organic compounds widely distributed in nature, have attracted significant interest due to their potential biological benefits. One such naphthoquinone is 3,5,8-trihydroxy-6-methoxy-2-(5-oxohexa-1,3-dienyl)-naphthanthene-1,4-dione (3,5,8-TMON), a compound produced by fungi. Despite its structural similarity to shikonin, limited research has been conducted to investigate its biological properties. Therefore, the objective of this study was to evaluate the effects of 3,5,8-TMON and its synthetic derivatives in the context of inflammation induced by lipopolysaccharide (LPS) and SARS-CoV-2 infection in vitro using cell cultures. 3,5,8-TMON was obtained by acid treatment of crude extracts of fermentation medium from Cordyceps sp., and two derivatives were accessed by reaction with phenylhydrazine under different conditions. The results revealed that the crude extract of the fungi (C. Ex) inhibited the activity of transcription factor NF-kB, as well as the production of nitric oxide (NO) and interleukin-6 (IL-6) when LPS induced it in RAW 264.7 cells. This inhibitory effect was observed at effective concentrations of 12.5 and 3.12 μg mL-1. In parallel, 3,5,8-TMON and the new derivatives 3 and 4 demonstrated the ability to decrease IL-6 production while increasing TNF, with a specific effect depending on the concentration. These concentration-dependent agonist and antagonist effects were observed in THP-1 cells. Furthermore, 3,5,8-TMON inhibited IL-6 production at concentrations of 12.5 and 3.12 μg mL-1 in Calu-3 cells during SARS-CoV-2 viral infection. These findings present promising opportunities for further research into the therapeutic potential of this class of naphthoquinone in the management of inflammation and viral infections.

Gold(III) complexes with thiosemicarbazone ligands: insights into their cytotoxic effects on lung cancer cells

Cancer continues to pose a global threat, underscoring the urgent need for more effective and safer treatment options. Gold-based compounds have recently emerged as promising candidates due to their diverse range of biological activities. In this study, three gold(III) complexes derived from thiosemicarbazone ligands have been synthesized, fully characterized, including their X-ray crystal structures. We conducted initial mode-of-action studies on DNA and BSA, followed by a comprehensive investigation into the cytotoxic effects of these novel gold(III) complexes on lung cancer cells (A549, H2052, and H28). The results demonstrated a concentration-dependent cytotoxic response, with H28 cells exhibiting the highest sensitivity to the treatment. Furthermore, the analysis of the cell cycle revealed that these compounds induce cell cycle arrest and promote apoptosis as a response to treatment. We also observed distinct morphological changes and increased oxidative stress, contributing significantly to cell death. Notably, these complexes exhibited the ability to suppress interleukin-6 production in mesothelioma cell lines, and this highlights their anti-inflammatory potential. To gain an initial understanding of cytotoxicity on healthy cells, hemolysis tests were conducted against human blood cells, with no evidence of hemolysis. Furthermore, a toxicity assessment through the in vivo Galleria mellonella model underscored the absence of detectable toxicity. These findings prove that these complexes are promising novel therapeutic agents for lung cancer.

Antinociceptive and anti-inflammatory properties of α-D-mannan from the yeast Kluyveromyces marxianus: evidence for a role in interleukin-6 inhibition.

The management of inflammatory states typically involves non-steroidal anti-inflammatory drugs (NSAIDs) and opiates. Understanding the mechanisms underlying the processing of nociceptive information from potential alternatives such as some polysaccharides may enable new and meaningful therapeutic approaches. In this study, α-D-mannan isolated from the Kluyveromyces marxianus cell wall produced antinociceptive effects in models of inflammatory pain (formalin and complete Freund's adjuvant tests). Furthermore, α-D-mannan reduced paw edema and interleukin-6 (IL-6) production after carrageenan-induced inflammation. The polysaccharide α-D-mannan was characterized by gas chromatography-mass spectrometry, methylation analysis, and spectroscopic techniques. Moreover, the Doehlert experimental design was applied to find the optimal conditions for biomass production, with the best conditions being 10.8g/L and 117h for the glucose concentration and the fermentation time, respectively. These results indicate that α-D-mannan from K. marxianus exerts anti-inflammatory and antinociceptive effects in mice, possibly via a mechanism dependent on the inhibition of IL-6 production.

Anti-inflammatory effects of cold atmospheric plasma irradiation on the THP-1 human acute monocytic leukemia cell line.

Cold atmospheric plasma (CAP) has been studied and clinically applied to treat chronic wounds, cancer, periodontitis, and other diseases. CAP exerts cytotoxic, bactericidal, cell-proliferative, and anti-inflammatory effects on living tissues by generating reactive species. Therefore, CAP holds promise as a treatment for diseases involving chronic inflammation and bacterial infections. However, the cellular mechanisms underlying these anti-inflammatory effects of CAP are still unclear. Thus, this study aimed to elucidate the anti-inflammatory mechanisms of CAP in vitro. The human acute monocytic leukemia cell line, THP-1, was stimulated with lipopolysaccharide and irradiated with CAP, and the cytotoxic effects of CAP were evaluated. Time-course differentiation of gene expression was analyzed, and key transcription factors were identified via transcriptome analysis. Additionally, the nuclear localization of the CAP-induced transcription factor was examined using western blotting. The results indicated that CAP showed no cytotoxic effects after less than 70 s of irradiation and significantly inhibited interleukin 6 (IL6) expression after more than 40 s of irradiation. Transcriptome analysis revealed many differentially expressed genes (DEGs) following CAP irradiation at all time points. Cluster analysis classified the DEGs into four distinct groups, each with time-dependent characteristics. Gene ontology and gene set enrichment analyses revealed CAP-induced suppression of IL6 production, other inflammatory responses, and the expression of genes related to major histocompatibility complex (MHC) class II. Transcription factor analysis suggested that nuclear factor erythroid 2-related factor 2 (NRF2), which suppresses intracellular oxidative stress, is the most activated transcription factor. Contrarily, regulatory factor X5, which regulates MHC class II expression, is the most suppressed transcription factor. Western blotting revealed the nuclear localization of NRF2 following CAP irradiation. These data suggest that CAP suppresses the inflammatory response, possibly by promoting NRF2 nuclear translocation.

Carvacrol protects mice against LPS-induced sepsis and attenuates inflammatory response in macrophages by modulating the ERK1/2 pathway

Macrophages play an important role in the development of life-threatening sepsis, which is characterized by multiorgan dysfunction, through their ability to produce inflammatory cytokines. Carvacrol is a phenolic compound that has been confirmed to possess strong anti‑inflammatory activity. In this study, we mainly investigated the effect of carvacrol on lipopolysaccharide (LPS)-induced macrophage proinflammatory responses and endotoxic shock. The results showed that carvacrol significantly reduced mouse body weight loss and ameliorated pathological damage to the liver, lung, and heart under LPS-induced sepsis. Carvacrol attenuated inflammatory responses by inhibiting the LPS-induced production of inflammatory cytokine interleukin-6 (IL-6) in vivo and in vitro. Mechanistically, carvacrol inhibited IL-6 production mainly through the ERK1/2 signalling pathway in macrophages. Furthermore, carvacrol improved the survival of septic mice. This study sheds light on the role of carvacrol in the pathogenesis of LPS-induced sepsis, and thus, its potential in treating sepsis patients may be considered.

GARCINIA COWA ROXB. ETHANOL EXTRACT INHIBITS INFLAMMATION IN LPS-INDUCED RAW 264.7 MACROPHAGES

Objective: The purpose of this study was to examine the effect of Garcinia cowa Roxb. Ethanol (EGC) extract in LPS-induced Raw 264.7 macrophages by observing the release of Tumor Necrosis Factor (TNF) and Interleukin-6 (IL-6).
 Methods: Using the MTT method, a cell viability assay was performed to observe the cytotoxic effect on Raw 264.7 macrophages. For 24 h, Raw 264.7 macrophages were incubated with various EGC concentrations (100, 50, 10, 1 and 0.1 µg/ml). The medium was taken out after 48 h of incubation, and 100 µl of MTT 0.5 mg/ml was then added. 100 µl DMSO was used to dissolve the crystals and absorbance was measured using a microplate reader. To investigate the activity of EGC to LPS-induced Raw 264.7 macrophages, the ELISA method was used. Supernatant was obtained after treating Raw 264.7 macrophages with complete medium, EGC samples, and LPS (10 g/ml) for 24 h. IL-6 and TNF-α levels were assessed using supernatants with ELISA kit.
 Results: Cytotoxic effect of EGC to Raw 264.7 macrophages occurred at a concentration of 100 µg/ml with the cell viability value of 59.5%. At a concentration of 50 µg/ml, no cytotoxic effect occurred and the cell viability value was 105.5%. So, the higher concentration of EGC used for further investigation is 50 µg/ml. It was shown that the production of IL 6 was suppressed by EGC at a concentration of 12.5 µg/ml. The inhibition of TNF-α production was only seen at the concentration of 12.5, 25 and 50 µg/ml; there was an increase of TNF-α production.
 Conclusion: It can be concluded that EGC can be developed as a natural immunomodulator that can inhibit inflammation by suppressing IL-6 production to prevent immune system disorders.

The ketone body β-hydroxybutyrate mitigates ILC2-driven airway inflammation by regulating mast cell function.

Ketone bodies are increasingly understood to have regulatory effects on immune cell function, with β-hydroxybutyrate (BHB) exerting a predominantly anti-inflammatory response. Dietary strategies to increase endogenous ketone body availability such as the ketogenic diet (KD) have recently been shown to alleviate inflammation of the respiratory tract. However, the role of BHB has not been addressed. Here, we observe that BHB suppresses group 2 innate lymphoid cell (ILC2)-mediated airway inflammation. Central to this are mast cells, which support ILC2 proliferation through interleukin-2 (IL-2). Suppression of the mast cell/IL-2 axis by BHB attenuates ILC2 proliferation and the ensuing type 2 cytokine response and immunopathology. Mechanistically, BHB directly inhibits mast cell function in part through GPR109A activation. Similar effects are achieved with either the KD or 1,3-butanediol. Our data reveal the protective role of BHB in ILC2-driven airway inflammation, which underscores the potential therapeutic value of ketone body supplementation for the management of asthma.

Coronavirus infection and psoriasis: relationship and consequences

As numerous scientific data show, despite the fact that patients with severe psoriasis have a high risk of coronavirus infection, COVID-19 in this group proceeds quite easily. However, many specialists have encountered an unusual exacerbation of the psoriatic process already after the infection, the reasons for which may be several. On the one hand, the skin is one of the target organs for SARS-CoV-2, on the other hand, exacerbations may be caused by the immune system response to the infection. The influence of specific therapy on the course of the psoriatic process is also not excluded. But interleukin status of patients with psoriasis is of the greatest interest. It is known that interleukin-6 (IL-6) plays an active role in pathogenesis of COVID-19 and cytokine storm arising at infection. It is also regarded as an indicator of inflammatory activity in psoriasis. In addition, IL-6 is involved in lipid and hepatobiliary disorders in this group of patients. It is also associated with IL-17, the role of which has been well studied in psoriasis and autoimmune hepatitis. Patients with psoriasis often have changes in biochemical blood parameters, similar to those seen with COVID-19. Combinations of all these factors can lead to exacerbation of psoriasis with predominance of erythroderma and toxic component. In our opinion, in such cases it is necessary to include in the therapy a systemic hepatoprotective drug containing glycyrrhizic acid. It has a pronounced anti-inflammatory effect, inhibits IL-6 production and allows to achieve significant improvement of psoriatic process in a short time.

Profiling Differential Effects of 5 Selective Serotonin Reuptake Inhibitors on TLRs-Dependent and -Independent IL-6 Production in Immune Cells Identifies Fluoxetine as Preferred Anti-Inflammatory Drug Candidate

Excessive proinflammatory cytokine production induced by abnormal activation of Toll-like receptor (TLR) signaling, for example, by SARS-CoV-2 infection, can cause a fatal cytokine storm. The selective serotonin reuptake inhibitors (SSRIs) fluoxetine and fluvoxamine, used to treat depression, were recently reported to reduce the risk of severe disease in patients with coronavirus disease 2019 (COVID-19), but the mechanisms of the anti-inflammatory effects of SSRIs, and which SSRI would be most suitable as an anti-inflammatory drug, remain unclear. Here, we examined the inhibitory effects of 5 FDA-approved SSRIs, paroxetine, fluoxetine, fluvoxamine, sertraline and escitalopram, on the production of interleukin-6 (IL-6) induced by stimulation with multiple TLR agonists in murine macrophages and dendritic cells, and on the production of cytokines induced by concanavalin A in murine lymphocytes. In J774.1 murine macrophage cells, pretreatment with SSRIs significantly suppressed IL-6 release induced by TLR3 agonist poly(I:C), TLR4 agonist LPS or TLR9 agonist CpG ODN, but did not affect IL-6 release induced by TLR7 agonists imiquimod or resiquimod. In accordance with the results obtained in J774.1 cells, pretreatment with SSRIs also suppressed IL-6 release induced by a TLR3, TLR4 or TLR9 agonist in bone marrow-derived dendritic cells and peritoneal cells of C57BL/6 mice. On the other hand, interestingly, sertraline alone among the SSRIs amplified IL-6 production induced by TLR7 agonists in murine dendritic cells, though not in macrophages. Concanavalin A-induced production of IL-6 or IL-2 in murine lymphocytes was suppressed by SSRIs, suggesting that SSRIs also inhibit TLRs-independent IL-6 production. Since SSRIs suppressed both IL-6 production induced by multiple TLR agonists in macrophages or dendritic cells and TLR-independent IL-6 production in lymphocytes, they are promising candidates for treatment of patients with cytokine storm, which is mediated by overactivation of multiple TLRs in a complex manner, leading to the so-called IL-6 amplifier, an IL-6 overproduction loop. However, the 5 SSRIs examined here all showed different effects. Overall, our results suggest that fluoxetine may be the most promising candidate as an anti-inflammatory drug. An examination of the structural requirements indicated that the N-methyl group of fluoxetine has a critical role in the inhibition of IL-6 production.

Interaction Between CD34+ Fibrocytes and Airway Smooth Muscle Promotes IL-8 Production and Akt/PRAS40/mTOR Signaling in Asthma.

BackgroundThe circulating progenitor cells of fibroblasts (fibrocytes) have been shown to infiltrate the airway smooth muscle compartment of asthma patients; however, the pathological significance of this discovery has yet to be elucidated. This study established a co-culture model of airway smooth muscle cells (ASMCs) and fibrocytes from asthmatic or normal subjects to evaluate innate cytokine production, corticosteroid responses, and signaling in ASMCs.MethodsCD34+ fibrocytes were purified from peripheral blood of asthmatic (Global Initiative for Asthma treatment step 4–5) and normal subjects and cultured for 5∼7 days. In a transwell plate, ASMCs were co-cultured with fibrocytes at a ratio of 2:1, ASMCs were cultured alone (control condition), and fibrocytes were cultured alone for 48 h. Measurements were obtained of interleukin-8 (IL-8), IL-6, IL-17, thymic stromal lymphopoietin, and IL-33 levels in the supernatant and IL-33 levels in the cell lysate of the co-culture. Screening for intracellular signaling in the ASMCs after stimulation was performed using condition medium from the patients’ co-culture (PtCM) or IL-8. mRNA and western blot analysis were used to analyze AKT/mTOR signaling in ASMCs stimulated via treatment with PtCM or IL-8.ResultsCompared with ASMCs cultured alone, IL-8 levels in the supernatant and IL-33 levels in the ASMCs lysate were significantly higher in samples co-cultured from asthmatics, but not in those co-cultured from normal subjects. Corticosteroid-induced suppression of IL-8 production was less pronounced in ASMCs co-cultured with fibrocytes from asthma patients than in ASMCs co-cultured from normal subjects. ASMCs stimulated using PtCM and IL-8 presented elevating activated AKT substrate PRAS40. Treatment with IL-8 and PtCM increased mRNA expression of mTOR and P70S6 kinases in ASMCs. Treatment with IL-8 and PtCM also significantly increased phosphorylation of AKT and mTOR subtract S6 ribosomal protein in ASMCs.ConclusionThe interaction between ASMCs and fibrocytes from asthmatic patients was shown to increase IL-8 and IL-33 production and promote AKT/mTOR signaling in ASMCs. IL-8 production in the co-culture from asthmatic patients was less affected by corticosteroid than was that in the co-culture from normal subjects. Our results elucidate the novel role of fibrocytes and ASMCs in the pathogenesis of asthma.

Leukotriene B4 receptor-2 contributes to KRAS-driven lung tumor formation by promoting interleukin-6-mediated inflammation

Although lung cancer is the leading cause of cancer-related deaths worldwide and KRAS is the most frequently mutated oncogene in lung cancer cases, the mechanism by which KRAS mutation drives lung cancer has not been fully elucidated. Here, we report that the expression levels of leukotriene B4 receptor-2 (BLT2) and its ligand-producing enzymes (5-LOX, 12-LOX) were highly increased by mutant KRAS and that BLT2 or 5-/12-LOX blockade attenuated KRAS-driven lung cell proliferation and production of interleukin-6 (IL-6), a principal proinflammatory mediator of lung cancer development. Next, we explored the roles of BLT2 and 5-/12-LOX in transgenic mice with lung-specific expression of mutant KRAS (KrasG12D) and observed that BLT2 or 5-/12-LOX inhibition decreased IL-6 production and tumor formation. To further determine whether BLT2 is involved in KRAS-driven lung tumor formation, we established a KrasG12D/BLT2-KO double-mutant mouse model. In the double-mutant mice, we observed significantly suppressed IL-6 production and lung tumor formation. Additionally, we observed high BLT2 expression in tissue samples from patients with KrasG12D-expressing lung adenocarcinoma, supporting the contributory role of BLT2 in KRAS-driven human lung cancer. Collectively, our results suggest that BLT2 is a potential contributor to KRAS-driven lung cancer and identify an attractive therapeutic target for KRAS-driven lung cancer.

Trimebutine suppresses Toll-like receptor 2/4/7/8/9 signaling pathways in macrophages

Because of the critical roles of Toll-like receptors (TLRs) and receptor for advanced glycation end-products (RAGE) in the pathophysiology of various acute and chronic inflammatory diseases, continuous efforts have been made to discover novel therapeutic inhibitors of TLRs and RAGE to treat inflammatory disorders. A recent study by our group has demonstrated that trimebutine, a spasmolytic drug, suppresses the high mobility group box 1‒RAGE signaling that is associated with triggering proinflammatory signaling pathways in macrophages. Our present work showed that trimebutine suppresses interleukin-6 (IL-6) production in lipopolysaccharide (LPS, a stimulant of TLR4)-stimulated macrophages of RAGE-knockout mice. In addition, trimebutine suppresses the LPS-induced production of various proinflammatory cytokines and chemokines in mouse macrophage-like RAW264.7 cells. Importantly, trimebutine suppresses IL-6 production induced by TLR2-and TLR7/8/9 stimulants. Furthermore, trimebutine greatly reduces mortality in a mouse model of LPS-induced sepsis. Studies exploring the action mechanism of trimebutine revealed that it inhibits the LPS-induced activation of IL-1 receptor-associated kinase 1 (IRAK1), and the subsequent activations of extracellular signal-related kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and nuclear factor-κB (NF-κB). These findings suggest that trimebutine exerts anti-inflammatory effects on TLR signaling by downregulating IRAK1‒ERK1/2‒JNK pathway and NF-κB activity, thereby indicating the therapeutic potential of trimebutine in inflammatory diseases. Therefore, trimebutine can be a novel anti-inflammatory drug-repositioning candidate and may provide an important scaffold for designing more effective dual anti-inflammatory drugs that target TLR/RAGE signaling.

A yeast-based screening system identified bakkenolide B contained in Petasites japonicus as an inhibitor of interleukin-2 production in a human T cell line.

Ca2+ signaling is related to various diseases such as allergies, diabetes, and cancer. We explored Ca2+ signaling inhibitors in natural resources using a yeast-based screening method and found bakkenolide B from the flower buds of edible wild plant, Petasites japonicus, using the YNS17 strain (zds1Δ erg3Δ pdr1/3Δ). Bakkenolide B exhibited growth-restoring activity against the YNS17 strain and induced Li+ sensitivity of wild-type yeast cells, suggesting that it inhibits the calcineurin pathway. Additionally, bakkenolide B inhibited interleukin-2 production at gene and protein levels in Jurkat cells, a human T cell line, but not the in vitro phosphatase activity of human recombinant calcineurin, an upstream regulator of interleukin-2 production. Furthermore, bakkenolide A showed weak activity in YNS17 and Jurkat cells compared with bakkenolide B. These findings revealed new biological effects and the structure-activity relationships of bakkenolides contained in P. japonicus as inhibitors of interleukin-2 production in human T cells.

Kaempferia parviflora extract inhibits TNF-α-induced release of MCP-1 in ovarian cancer cells through the suppression of NF-κB signaling

Ovarian clear cell carcinoma (OCCC) is an uncommon subtype of epithelial cell ovarian cancers (EOCs) that has poor response to conventional platinum-based therapy. Therefore, finding new potential therapeutic agents is required. Since inflammatory cytokine, tumor necrosis factor alpha (TNF-α), is strongly expressed in EOCs and associated with the level of tumor grade, disruption of this inflammation pathway may provide another potential target for OCCC treatment. We previously reported that Kaempferia parviflora (KP) extract decreased cell proliferation and induced apoptosis. However, the effects of KP on OCCC, especially the aspects related to inflammatory cytokines, have not been elucidated. Our current study demonstrated the effects of KP extract on cytokine production in TNF-α-induced OCCC TOV-21G cell line. This study showed that KP extract inhibited interleukin 6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) production at both transcription and translation levels via the suppression of nuclear factor-kappa B (NF-κB) signal transduction. In contrast, KP extract increased the expression of inhibitor kappa B (IκB) protein which may delay NF-κB translocation into the nucleus upon TNF-α activation. Moreover, the suppression of cytokines released from KP treated-TOV-21G reduced the migration of monocyte cell (THP-1). KP extract also exhibited the inhibition of IL-6 and MCP-1 production from THP-1 activated by lipopolysaccharides (LPS). Cells treated with KP extract exhibited a decrease in extracellular signal-regulated kinases (ERK1/2) and protein kinase B (AKT) phosphorylation and induced myeloid leukemia cell differentiation protein Mcl-1 (MCL-1) expression. Suppression of inflammatory cytokine and chemokine production and inhibition of tumor-associated macrophage (TAM) migration support the possibility of using KP for OCCC treatment.

Loss of PGRMC1 Delays the Progression of Hepatocellular Carcinoma via Suppression of Pro-Inflammatory Immune Responses.

Simple SummaryProgesterone receptor membrane component 1 (PGRMC1) and epidermal growth factor receptor (EGFR) are highly expressed in various cancers. Here, we first analyzed two sets of clinical data and found that the levels of PGRMC1 and EGFR in hepatocellular carcinomas (HCCs) were both inversely correlated with the survival of HCC patients. Accordingly, by using a carcinogen-induced mouse model of HCC, we found that Pgrmc1 knockout suppressed HCC development and extended the lifespan of HCC-bearing mice. In the acute setting of high-dose carcinogen administration, Pgrmc1 knockout was associated with increases in hepatic necrosis and decreases in the production of the pro-inflammatory cytokine IL-6. Indeed, silencing of Pgrmc1 in murine macrophages suppressed IL-6 production and NF-κB activity, and this process was significantly mediated by EGFR. Our study shows that Pgrmc1 affects the development of HCCs by regulating the EGFR-mediated inflammatory responses. Pgrmc1 may serve as a biomarker and a therapeutic target of HCC.Pgrmc1 is a non-canonical progesterone receptor related to the lethality of various types of cancer. PGRMC1 has been reported to exist in co-precipitated protein complexes with epidermal growth factor receptor (EGFR), which is considered a useful therapeutic target in hepatocellular carcinoma (HCC). Here, we investigated whether Pgrmc1 is involved in HCC progression. In clinical datasets, PGRMC1 transcription level was positively correlated with EGFR levels; importantly, PGRMC1 level was inversely correlated with the survival duration of HCC patients. In a diethylnitrosamine (DEN)-induced murine model of HCC, the global ablation of Pgrmc1 suppressed the development of HCC and prolonged the survival of HCC-bearing mice. We further found that increases in hepatocyte death and suppression of compensatory proliferation in the livers of DEN-injured Pgrmc1-null mice were concomitant with decreases in nuclear factor κB (NF-κB)-dependent production of interleukin-6 (IL-6). Indeed, silencing of Pgrmc1 in murine macrophages led to reductions in NF-κB activity and IL-6 production. We found that the anti-proinflammatory effect of Pgrmc1 loss was mediated by reductions in EGFR level and its effect was not observed after exposure of the EGFR inhibitor erlotinib. This study reveals a novel cooperative role of Pgrmc1 in supporting the EGFR-mediated development of hepatocellular carcinoma, implying that pharmacological suppression of Pgrmc1 may be a useful strategy in HCC treatment.

Suppressor of cytokine signalling 3 (SOCS3) expressed in podocytes attenuates glomerulonephritis and suppresses autoantibody production in an imiquimod-induced lupus model

ObjectiveRecently, podocytes have been recognised not only as a physical barrier to prevent urinary protein loss but also as producers of proinflammatory cytokines. However, the roles of podocytes in the...

Ellagitannins from Rosa roxburghii suppress poly(I:C)-induced IL-8 production in human keratinocytes.

The anti-inflammatory effects of a 50% aqueous extract of Rosa roxburghii fruit (RRFE) and two ellagitannins (strictinin and casuarictin) isolated from the RRFE were evaluated in a cell model of skin inflammation induced by self-RNA released from epidermal cells damaged by UV ray (UVR) irradiation. The RRFE inhibited interleukin-8 (IL-8) mRNA expression in normal human epidermal keratinocytes (NHEKs) stimulated with polyinosinic:polycytidylic acid (poly(I:C)), a ligand of toll-like receptor-3 (TLR-3). The plant-derived anti-inflammatory agents, dipotassium glycyrrhizinate (GK2) and allantoin, had no influence on the IL-8 expression. The purified compounds, strictinin and casuarictin, inhibited the IL-8 mRNA expression and IL-8 release induced in NHEKs by poly(I:C). These ellagitannins were thus found to be responsible for the biological activity exhibited by the RRFE. This study demonstrates that RRFE and isolated RRFE compounds show promise as ingredients for products formulated to improve skin disorders induced by UVR irradiation.