Displaying all 12 publications

Abstract:
Sort:
  1. Anti-inflammatory effect of mushrooms in dengue-infected human monocytes
    Ellan K, Thayan R, Phan CW, Sabaratnam V
    Trop Biomed, 2019 Dec 01;36(4):1087-1098.
    PMID: 33597478
    Pathogenesis of dengue fever has been associated with the activation of the cytokine cascade that triggered inflammatory responses. The inflammatory reactions in dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS) are the main cause of haemorrhagic manifestations, coagulation disorders, vascular permeability, hypotension and shock which could exacerbate the condition of the disease. In an earlier study, extracts belonging to Lignosus rhinocerotis, Pleurotus giganteus, Hericium erinaceus, Schizophyllum commune and Ganoderma lucidium mushrooms were screened for antidengue virus activities. We found that hot aqueous extract (HAE) and aqueous soluble separated from ethanol extract (ASE) exhibited their potential to reduce dengue viral load which were observed in plaque reduction assay and real-time RT-PCR. In continuation of our previous findings, this study was initiated to further investigate the other aspect; the anti-inflammatory activities of HAE and ASE of L. rhinocerotis, P. giganteus, H. erinaceus, S. commune and G. lucidium on human monocytes infected with dengue virus-2 (DENV-2) New guinea C strain. Human monocytes infected with DENV-2 were treated with mushroom extracts for 48 hours. The cytokine profile coincides with dengue infection, i.e. IFN-γ, TNF-α, IL-1β, IL-6, IL-8, and IL-10 were measured by BD OptEIATM Elisa Kit. The expression of these cytokines was significantly elevated in untreated infected cells two days after infection. However, after treated with mushroom extracts prominent anti-inflammatory effect were detected towards IFN-γ, IL-10, TNF-α, IL-6, and IL-1β. The most significant anti-inflammatory effects were detected in HAE of G. lucidium, S. commune, P. giganteus and ASE of L. rhinocerotis and the effects were comparable with dexamethasone, the reference inhibitor. These results demonstrated that mushroom HAE or ASE could successfully have suppressed cytokine production in dengue-infected monocytes and has a great potential to develop an antiinflammatory agent from mushroom extract for the treatment of dengue infection.
    Matched MeSH terms: Monocytes/drug effects*
  2. Effects of R-salbutamol on the inflammatory response and acute lung injury in endotoxemic mice
    Beng H, Hu J, Wang S, Liang X, Qin H, Tan W
    Int Immunopharmacol, 2023 Aug;121:110482.
    PMID: 37364330 DOI: 10.1016/j.intimp.2023.110482
    Salbutamol, which consists of an R-isomer and S-isomer, is an effective and widely used β2 adrenoreceptor agonist that may possess anti-inflammatory properties in addition to its bronchodilator activity. Whether the salbutamol R-isomer has advantages over its racemic mixture and effectiveness in treating endotoxemia and endotoxin-induced lung injury has not been well studied. In this study, we investigated the preventive and therapeutic effects of R-salbutamol (R-sal), S-salbutamol (S-sal), and their racemic mixture (Rac-sal) on a mouse model of lipopolysaccharide (LPS)-induced endotoxemia. Dexamethasone (Dex) was used for comparison. The results showed that R-sal markedly improved the 7-day survival rate of endotoxic mice when administered before and after LPS treatment. Dex was toxic and accelerated the death of endotoxic mice when administered before LPS injection. Histological examination of the lungs revealed that the LPS challenge resulted in acute lung damage, including inflammatory cell infiltration, thickened alveolar septa, and congestion. R-sal pre-treatment effectively inhibited these changes, accompanied by markedly reduced lung myeloperoxidase levels, serum cytokine levels, and lactate release, significant restoration of lymphocyte count, and reduction of monocyte count. This may have occurred through inhibition of M1 macrophage inflammatory responses by enhancement of β-arrestin2 expression and suppression of NF-κB activation. Rac-sal exhibited diminished effects compared to that of R-sal, while S-sal showed enhanced release of some inflammatory cytokines. In addition, R-sal pre-treatment showed a better improvement in prognostic pulmonary function on day 4 compared to that by Rac-sal. Collectively, our results indicate the potential benefits of R-sal in regulating inflammatory responses to endotoxemia and endotoxin-induced lung injury.
    Matched MeSH terms: Monocytes/drug effects
  3. Fulltext Primary human monocyte differentiation regulated by Nigella sativa pressed oil
    Mat MC, Mohamed AS, Hamid SS
    Lipids Health Dis, 2011;10:216.
    PMID: 22104447 DOI: 10.1186/1476-511X-10-216
    Oxidized low density lipoprotein plays an important role in development of foam cells in atherosclerosis. The study was focused on regulation of primary human monocyte growth and CD11b expression in presence of Nigella sativa oil.
    Matched MeSH terms: Monocytes/drug effects
  4. Fulltext Generation of dendritic cells from acute myeloid leukaemia cells and monocytes: our local experience
    Lim MN, Leong CF, Cheong SK, Seow HF
    Malays J Pathol, 2003 Dec;25(2):107-12.
    PMID: 16196366
    Dendritic cells (DC) are efficient and potent antigen-presenting cells. Pilot clinical trials indicated that DC loaded with tumour antigen could induce tumour-specific immune responses in various cancers including B-cell lymphoma, melanoma and prostate cancer. Owing to extensively low number of DC in the blood circulation, a variety of sources have been used to generate DC including monocytes, CD34+ stem cells and even with leukaemic blast cells. We demonstrate here a simple method to generate DC from acute myeloid leukaemia (AML) cells and monocytes from healthy donor or remission samples. AML cells or monocytes were cultured in RPMI 1640 media supplemented with foetal bovine serum or autologous serum where possible and different combinations of cytokines GM-CSF, IL-4 and TNF-alpha. The generated DC were evaluated for their morphology by phase contrast microscopy and May Grunwald Giemsa staining. Viability of cells was determined by trypan blue dye exclusion. Percentage of yields and immunophenotypes were carried out by flow cytometry. We found that cultured AML cells and monocytes developed morphological and immuno-phenotypic characteristics of DC. Monocytes are better than AML blast in generating DC and serve as a ready source for dendritic cell vaccine development.
    Matched MeSH terms: Monocytes/drug effects
  5. In vitro evaluation of the involvement of Nrf2 in maslinic acid-mediated anti-inflammatory effects in atheroma pathogenesis
    Ooi BK, Phang SW, Yong PVC, Chellappan DK, Dua K, Khaw KY, et al.
    Life Sci, 2021 Aug 01;278:119658.
    PMID: 34048809 DOI: 10.1016/j.lfs.2021.119658
    AIMS: Maslinic acid (MA) is a naturally occurring pentacyclic triterpene known to exert cardioprotective effects. This study aims to investigate the involvement of nuclear factor erythroid 2-related factor 2 (Nrf2) for MA-mediated anti-inflammatory effects in atheroma pathogenesis in vitro, including evaluation of tumor necrosis factor-alpha (TNF-α)-induced monocyte recruitment, oxidized low-density lipoprotein (oxLDL)-induced scavenger receptors expression, and nuclear factor-kappa B (NF-ĸB) activity in human umbilical vein endothelial cells (HUVECS) and human acute monocytic leukemia cell line (THP-1) macrophages.

    MATERIALS AND METHODS: An in vitro monocyte recruitment model utilizing THP-1 and HUVECs was developed to evaluate TNF-α-induced monocyte adhesion and trans-endothelial migration. To study the role of Nrf2 for MA-mediated anti-inflammatory effects, Nrf2 inhibitor ML385 was used as the pharmacological inhibitor. The expression of Nrf2, monocyte chemoattractant protein-1 (MCP-1), vascular cell adhesion molecule 1 (VCAM-1), cluster of differentiation 36 (CD36), and scavenger receptor type A (SR-A) in HUVECs and THP-1 macrophages were investigated using RT-qPCR and Western blotting. The NF-κB activity was determined using NF-κB (p65) Transcription Factor Assay Kit.

    KEY FINDINGS: The results showed opposing effects of MA on Nrf2 expression in HUVECs and THP-1 macrophages. MA suppressed TNF-α-induced Nrf2 expression in HUVECs, but enhanced its expression in THP-1 macrophages. Combined effects of MA and ML385 suppressed MCP-1, VCAM-1, and SR-A expressions. Intriguingly, at the protein level, ML385 selectively inhibited SR-A but enhanced CD36 expression. Meanwhile, ML385 further enhanced MA-mediated inhibition of NF-κB activity in HUVECs. This effect, however, was not observed in THP-1 macrophages.

    SIGNIFICANCE: MA attenuated foam cell formation by suppressing VCAM-1, MCP-1, and SR-A expression, as well as NF-κB activity, possibly through Nrf2 inhibition. The involvement of Nrf2 for MA-mediated anti-inflammatory effects however differs between HUVECs and macrophages. Future investigations are warranted for a detailed evaluation of the contributing roles of Nrf2 in foam cells formation.

    Matched MeSH terms: Monocytes/drug effects
  6. Inhibition of Human Group IIA-Secreted Phospholipase A2 and THP-1 Monocyte Recruitment by Maslinic Acid
    Yap WH, Ahmed N, Lim YM
    Lipids, 2016 10;51(10):1153-1159.
    PMID: 27540737 DOI: 10.1007/s11745-016-4186-1
    Maslinic acid is a natural pentacyclic triterpenoid which has anti-inflammatory properties. A recent study showed that secretory phospholipase A2 (sPLA2) may be a potential binding target of maslinic acid. The human group IIA (hGIIA)-sPLA2 is found in human sera and their levels are correlated with severity of inflammation. This study aims to determine whether maslinic acid interacts with hGIIA-sPLA2 and inhibits inflammatory response induced by this enzyme. It is shown that maslinic acid enhanced intrinsic fluorescence of hGIIA-sPLA2 and inhibited its enzyme activity in a concentration-dependent manner. Molecular docking revealed that maslinic acid binds to calcium binding and interfacial phospholipid binding site, suggesting that it inhibit access of catalytic calcium ion for enzymatic reaction and block binding of the enzyme to membrane phospholipid. The hGIIA-sPLA2 enzyme is also responsible in mediating monocyte recruitment and differentiation. Results showed that maslinic acid inhibit hGIIA-sPLA2-induced THP-1 cell differentiation and migration, and the effect observed is specific to hGIIA-sPLA2 as cells treated with maslinic acid alone did not significantly affect the number of adherent and migrated cells. Considering that hGIIA-sPLA2 enzyme is known to hydrolyze glyceroacylphospholipids present in lipoproteins and cell membranes, maslinic acid may bind and inhibit hGIIA-sPLA2 enzymatic activity, thereby reduces the release of fatty acids and lysophospholipids which stimulates monocyte migration and differentiation. This study is the first to report on the molecular interaction between maslinic acid and inflammatory target hGIIA-sPLA2 as well as its effect towards hGIIA-sPLA2-induced THP-1 monocyte adhesive and migratory capabilities, an important immune-inflammation process in atherosclerosis.
    Matched MeSH terms: Monocytes/drug effects
  7. Fulltext Alpha-1 antitrypsin augmentation therapy decreases miR-199a-5p, miR-598 and miR-320a expression in monocytes via inhibition of NFκB
    Hassan T, de Santi C, Mooney C, McElvaney NG, Greene CM
    Sci Rep, 2017 10 23;7(1):13803.
    PMID: 29062067 DOI: 10.1038/s41598-017-14310-2
    Alpha-1 antitrypsin (AAT) augmentation therapy involves infusion of plasma-purified AAT to AAT deficient individuals. Whether treatment affects microRNA expression has not been investigated. This study's objectives were to evaluate the effect of AAT augmentation therapy on altered miRNA expression in monocytes and investigate the mechanism. Monocytes were isolated from non-AAT deficient (MM) and AAT deficient (ZZ) individuals, and ZZs receiving AAT. mRNA (qRT-PCR, microarray), miRNA (miRNA profiling, qRT-PCR), and protein (western blotting) analyses were performed. Twenty one miRNAs were differentially expressed 3-fold between ZZs and MMs. miRNA validation studies demonstrated that in ZZ monocytes receiving AAT levels of miR-199a-5p, miR-598 and miR-320a, which are predicted to be regulated by NFκB, were restored to levels similar to MMs. Validated targets co-regulated by these miRNAs were reciprocally increased in ZZs receiving AAT in vivo and in vitro. Expression of these miRNAs could be increased in ZZ monocytes treated ex vivo with an NFκB agonist and decreased by NFκB inhibition. p50 and p65 mRNA and protein were significantly lower in ZZs receiving AAT than untreated ZZs. AAT augmentation therapy inhibits NFκB and decreases miR-199a-5p, miR-598 and miR-320a in ZZ monocytes. These NFκB-inhibitory properties may contribute to the anti-inflammatory effects of AAT augmentation therapy.
    Matched MeSH terms: Monocytes/drug effects
  8. The synthetic curcuminoid BHMC restores endotoxin-stimulated HUVEC dysfunction:Specific disruption on enzymatic activity of p38 MAPK
    Tham CL, Hazeera Harith H, Wai Lam K, Joong Chong Y, Singh Cheema M, Roslan Sulaiman M, et al.
    Eur J Pharmacol, 2015 Feb 15;749:1-11.
    PMID: 25560198 DOI: 10.1016/j.ejphar.2014.12.015
    2,6-bis-(4-hydroxyl-3-methoxybenzylidine)cyclohexanone (BHMC) has been proven to selectively inhibit the synthesis of proinflammatory mediators in lipopolysaccharide-induced U937 monocytes through specific interruption of p38 Mitogen-Activated Protein Kinase enzymatic activity and improves the survival rate in a murine lethal sepsis model. The present study addressed the effects of BHMC upon lipopolysaccharide-induced endothelial dysfunction in human umbilical vein endothelial cells to determine the underlying mechanisms. The cytotoxicity effect of BHMC on HUVEC were determined by MTT assay. The effects of BHMC on endothelial dysfunction induced by lipopolysaccharide such as endothelial hyperpermeability, monocyte-endothelial adhesion, transendothelial migration, up-regulation of adhesion molecules and chemokines were evaluated. The effects of BHMC at transcriptional and post-translational levels were determined by Reverse Transcriptase-Polymerase Chain Reaction and Western Blots. The mode of action of BHMC was dissected by looking into the activation of Nuclear Factor-kappa B and Mitogen-Activated Protein Kinases. BHMC concentration-dependently reduced endothelial hyperpermeability, leukocyte-endothelial cell adhesion and monocyte transendothelial migration through inhibition of the protein expression of adhesion molecules (Intercellular Adhesion Molecule-1 and Vascular Cell Adhesion Molecule-1) and secretion of chemokines (Monocyte Chemotactic Protein-1) at the transcriptional level. BHMC restored endothelial dysfunction via selective inhibition of p38 Mitogen-Activated Protein Kinase enzymatic activity which indirectly prevents the activation of Nuclear Factor-kappaB and Activator Protein-1 transcription factors. These findings further support earlier observations on the inhibition of BHMC on inflammatory events through specific disruption of p38 Mitogen-Activated Protein Kinase enzymatic activity and provide new insights into the inhibitory effects of BHMC on lipopolysaccharide-induced endothelial dysfunction.
    Matched MeSH terms: Monocytes/drug effects
  9. Cardamonin, inhibits pro-inflammatory mediators in activated RAW 264.7 cells and whole blood
    Ahmad S, Israf DA, Lajis NH, Shaari K, Mohamed H, Wahab AA, et al.
    Eur J Pharmacol, 2006 May 24;538(1-3):188-94.
    PMID: 16650843
    Some chalcones, such as hydroxychalcones have been reported previously to inhibit major pro-inflammatory mediators such as nitric oxide (NO), prostaglandin E(2) (PGE(2)), tumor necrosis factor-alpha (TNF-alpha) and reactive oxygen species production by suppressing inducible enzyme expression via inhibition of the mitogen-activated protein kinase (MAPK) pathway and nuclear translocation of critical transcription factors. In this report, the effects of cardamonin (2',4'-dihydroxy-6'-methoxychalcone), a chalcone that we have previously isolated from Alpinia rafflesiana, was evaluated upon two cellular systems that are repeatedly used in the analysis of anti-inflammatory bioactive compounds namely RAW 264.7 cells and whole blood. Cardamonin inhibited NO and PGE(2) production from lipopolysaccharide- and interferon-gamma-induced RAW cells and whole blood with IC(50) values of 11.4 microM and 26.8 microM, respectively. Analysis of thromboxane B(2) (TxB(2)) secretion from whole blood either stimulated via the COX-1 or COX-2 pathway revealed that cardamonin inhibits the generation of TxB(2) via both pathways with IC(50) values of 2.9 and 1.1 microM, respectively. Analysis of IC(50) ratios determined that cardamonin was more COX-2 selective in its inhibition of TxB(2) with a ratio of 0.39. Cardamonin also inhibited the generation of intracellular reactive oxygen species and secretion of TNF-alpha from RAW 264.7 cells in a dose responsive manner with IC(50) values of 12.8 microM and 4.6 microM, respectively. However, cardamonin was a moderate inhibitor of lipoxygenase activity when tested in an enzymatic assay system, in which not a single concentration tested was able to cause an inhibition of more than 50%. Our results suggest that cardamonin acts upon major pro-inflammatory mediators in a similar fashion as described by previous work on other closely related synthetic hydroxychalcones and strengthens the conclusion of the importance of the methoxyl moiety substitution on the 4' or 6' locations of the A benzene ring.
    Matched MeSH terms: Monocytes/drug effects
  10. Cryptotanshinone attenuates in vitro oxLDL-induced pre-lesional atherosclerotic events
    Ang KP, Tan HK, Selvaraja M, Kadir AA, Somchit MN, Akim AM, et al.
    Planta Med, 2011 Nov;77(16):1782-7.
    PMID: 21614753 DOI: 10.1055/s-0030-1271119
    Development of early stage atherosclerosis involves the activation of endothelial cells by oxidized low-density lipoprotein (oxLDL) with subsequent increases in endothelial permeability and expression of adhesion molecules favoring the adherence of monocytes to the endothelium. Cryptotanshinone (CTS), a major compound derived from the Chinese herb Salvia miltiorrhiza, is known for its protective effects against cardiovascular diseases. The aim of this study was to determine whether CTS could prevent the oxLDL-induced early atherosclerotic events. OxLDL (100 µg/mL) was used to increase endothelial permeability and induce monocyte-endothelial cell adhesion in human umbilical vein endothelial cells (HUVECs). Endothelial nitric oxide (NO) concentrations, a permeability-regulating molecule, and expressions of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were measured. Results show that a) endothelial hyperpermeability was suppressed by 94 % (p 
    Matched MeSH terms: Monocytes/drug effects
  11. 1'-Acetoxychavicol acetate inhibits NLRP3-dependent inflammasome activation via mitochondrial ROS suppression
    Sok SPM, Ori D, Wada A, Okude H, Kawasaki T, Momota M, et al.
    Int Immunol, 2021 06 18;33(7):373-386.
    PMID: 33830232 DOI: 10.1093/intimm/dxab016
    The nucleotide-binding oligomerization domain-like receptor (NLR) family pyrin domain containing (NLRP) 3 inflammasome is a multiprotein complex that triggers Caspase-1-mediated IL-1β production and pyroptosis, and its dysregulation is associated with the pathogenesis of inflammatory diseases. 1'-Acetoxychavicol acetate (ACA) is a natural compound in the rhizome of tropical ginger Alpinia species with anti-microbial, anti-allergic and anti-cancer properties. In this study, we found that ACA suppressed NLRP3 inflammasome activation in mouse bone marrow-derived macrophages and human THP-1 monocytes. ACA inhibited Caspase-1 activation and IL-1β production by NLRP3 agonists such as nigericin, monosodium urate (MSU) crystals, and ATP. Moreover, it suppressed oligomerization of the adapter molecule, apoptosis-associated speck-like protein containing a CARD (ASC), and Caspase-1-mediated cleavage of pyroptosis executor Gasdermin D. Mechanistically, ACA inhibited generation of mitochondrial reactive oxygen species (ROS) and prevented release of oxidized mitochondrial DNA, which trigger NLRP3 inflammasome activation. ACA also prevented NLRP3 inflammasome activation in vivo, as evidenced in the MSU crystal-induced peritonitis and dextran sodium sulfate-induced colitis mouse models accompanied by decreased Caspase-1 activation. Thus, ACA is a potent inhibitor of the NLRP3 inflammasome for prevention of NLRP3-associated inflammatory diseases.
    Matched MeSH terms: Monocytes/drug effects
  12. Barrier protective effects of 2,4,6-trihydroxy-3-geranyl acetophenone on lipopolysaccharides-stimulated inflammatory responses in human umbilical vein endothelial cells
    Chong YJ, Musa NF, Ng CH, Shaari K, Israf DA, Tham CL
    J Ethnopharmacol, 2016 Nov 04;192:248-255.
    PMID: 27404229 DOI: 10.1016/j.jep.2016.07.032
    PHARMOCOLOGICAL RELEVANCE: 2,4,6-trihydroxy-3-geranyl acetophenone (tHGA), is a phloroglucinol compound found naturally in Melicope ptelefolia. Melicope ptelefolia has been used traditionally for centuries as natural remedy for wound infections and inflammatory diseases.

    AIM OF THE STUDY: Endothelial barrier dysfunction is a pathological hallmark of many diseases and can be caused by lipopolysaccharides (LPS) stimulation. Therefore, this study aims to investigate the possible barrier protective effects of tHGA upon LPS-stimulated inflammatory responses in human umbilical vein endothelial cells (HUVECs).

    MATERIALS AND METHODS: HUVECs were pretreated with tHGA prior to LPS stimulation, where inflammatory parameters including permeability, monocyte adhesion and migration, and release of pro-inflammatory mediators were examined. Additionally, the effect of tHGA on F-actin rearrangement and adhesion protein expression of LPS-stimulated HUVECs was evaluated.

    RESULTS: It was found that pretreatment with tHGA inhibited monocyte adhesion and transendothelial migration, reduced endothelial hyperpermeability and secretion of prostaglandin E2 (PGE2). Additionally, tHGA inhibited cytoskeletal rearrangement and adhesion protein expression on LPS-stimulated HUVECs.

    CONCLUSION: As the regulation of endothelial barrier dysfunction can be one of the therapeutic strategies to improve the outcome of inflammation, tHGA may be able to preserve vascular barrier integrity of endothelial cells following LPS-stimulated dysfunction, thereby endorsing its potential usefulness in vascular inflammatory diseases.

    Matched MeSH terms: Monocytes/drug effects
Related Terms
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links