Displaying publications 1 - 20 of 69 in total

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  1. Chee Wezen X, Chandran A, Eapen RS, Waters E, Bricio-Moreno L, Tosi T, et al.
    J Chem Inf Model, 2022 May 23;62(10):2586-2599.
    PMID: 35533315 DOI: 10.1021/acs.jcim.2c00300
    Lipoteichoic acid synthase (LtaS) is a key enzyme for the cell wall biosynthesis of Gram-positive bacteria. Gram-positive bacteria that lack lipoteichoic acid (LTA) exhibit impaired cell division and growth defects. Thus, LtaS appears to be an attractive antimicrobial target. The pharmacology around LtaS remains largely unexplored with only two small-molecule LtaS inhibitors reported, namely "compound 1771" and the Congo red dye. Structure-based drug discovery efforts against LtaS remain unattempted due to the lack of an inhibitor-bound structure of LtaS. To address this, we combined the use of a molecular docking technique with molecular dynamics (MD) simulations to model a plausible binding mode of compound 1771 to the extracellular catalytic domain of LtaS (eLtaS). The model was validated using alanine mutagenesis studies combined with isothermal titration calorimetry. Additionally, lead optimization driven by our computational model resulted in an improved version of compound 1771, namely, compound 4 which showed greater affinity for binding to eLtaS than compound 1771 in biophysical assays. Compound 4 reduced LTA production in S. aureus dose-dependently, induced aberrant morphology as seen for LTA-deficient bacteria, and significantly reduced bacteria titers in the lung of mice infected with S. aureus. Analysis of our MD simulation trajectories revealed the possible formation of a transient cryptic pocket in eLtaS. Virtual screening (VS) against the cryptic pocket led to the identification of a new class of inhibitors that could potentiate β-lactams against methicillin-resistant S. aureus. Our overall workflow and data should encourage further drug design campaign against LtaS. Finally, our work reinforces the importance of considering protein conformational flexibility to a successful VS endeavor.
    Matched MeSH terms: Lipopolysaccharides/pharmacology
  2. Sarmiento ME, Chin KL, Lau NS, Aziah I, Ismail N, Norazmi MN, et al.
    Fish Shellfish Immunol, 2021 Oct;117:148-156.
    PMID: 34358702 DOI: 10.1016/j.fsi.2021.08.001
    Horseshoe crabs (HSCs) are living fossil species of marine arthropods with a long evolutionary history spanning approximately 500 million years. Their survival is helped by their innate immune system that comprises cellular and humoral immune components to protect them against invading pathogens. To help understand the genetic mechanisms involved, the present study utilised the Illumina HiSeq platform to perform transcriptomic analysis of hemocytes from the HSC, Tachypleus gigas, that were challenged with lipopolysaccharides (LPS). The high-throughput sequencing resulted in 352,077,208 and 386,749,136 raw reads corresponding to 282,490,910 and 305,709,830 high-quality mappable reads for the control and LPS-treated hemocyte samples, respectively. Based on the log-fold change of > 0.3 or 
    Matched MeSH terms: Lipopolysaccharides/pharmacology*
  3. Hambali A, Jusril NA, Md Hashim NF, Abd Manan N, Adam SK, Mehat MZ, et al.
    J Alzheimers Dis, 2024;99(s1):S119-S138.
    PMID: 38250772 DOI: 10.3233/JAD-230875
    BACKGROUND: Neuroinflammation and oxidative stress can aggravate the progression of Alzheimer's disease (AD). Centella asiatica has been traditionally consumed for memory and cognition. The triterpenes (asiaticoside, madecassoside, asiatic acid, madecassic acid) have been standardized in the ethanolic extract of Centella asiatica (SECA). The bioactivity of the triterpenes in different solvent polarities of SECA is still unknown.

    OBJECTIVE: In this study, the antioxidative and anti-neuroinflammatory effects of SECA and its fractions were explored on lipopolysaccharides (LPS)-induced microglial cells.

    METHODS: HPLC measured the four triterpenes in SECA and its fractions. SECA and its fractions were tested for cytotoxicity on microglial cells using MTT assay. NO, pro-inflammatory cytokines (TNF-α, IL-6, IL-1β), ROS, and MDA (lipid peroxidation) produced by LPS-induced microglial cells were measured by colorimetric assays and ELISA. Nrf2 and HO-1 protein expressions were measured using western blotting.

    RESULTS: The SECA and its fractions were non-toxic to BV2 microglial cells at tested concentrations. The levels of NO, TNF-α, IL-6, ROS, and lipid peroxidation in LPS-induced BV2 microglial cells were significantly reduced (p 

    Matched MeSH terms: Lipopolysaccharides/pharmacology
  4. Jalil J, Sabandar CW, Ahmat N, Jamal JA, Jantan I, Aladdin NA, et al.
    Molecules, 2015 Feb 16;20(2):3206-20.
    PMID: 25690285 DOI: 10.3390/molecules20023206
    The crude methanol extracts and fractions of the root and stem barks of Dillenia serrata Thunb. showed 64% to 73% inhibition on the production of prostaglandin E2 (PGE2) in lipopolysaccharide-induced human whole blood using a radioimmunoassay technique. Three triterpenoids isolated from the root bark of the plant, koetjapic (1), 3-oxoolean-12-en-30-oic (2), and betulinic (3) acids, exhibited significant concentration-dependent inhibitory effects on PGE2 production with IC50 values of 1.05, 1.54, and 2.59 μM, respectively, as compared with the positive control, indomethacin (IC50 = 0.45 μM). Quantification of compounds 1 and 3 in the methanol extracts and fractions were carried out by using a validated reversed-phase high performance liquid chromatography (RP-HPLC) method. The ethyl acetate fraction of the stem bark showed the highest content of both compound 1 (15.1%) and compound 3 (52.8%). The strong inhibition of the extracts and fractions on cyclooxygenase-2 (COX-2) enzymatic activity was due to the presence of their major constituents, especially koetjapic and betulinic acids.
    Matched MeSH terms: Lipopolysaccharides/pharmacology
  5. Abdo Qaid EY, Abdullah Z, Zakaria R, Long I
    Int J Mol Sci, 2022 Nov 03;23(21).
    PMID: 36362262 DOI: 10.3390/ijms232113474
    Neuroinflammation following lipopolysaccharide (LPS) administration induces locomotor deficits and anxiety-like behaviour. In this study, minocycline was compared to memantine, an NMDA receptor antagonist, for its effects on LPS-induced locomotor deficits and anxiety-like behaviour in rats. Adult male Sprague Dawley rats were administered either two different doses of minocycline (25 or 50 mg/kg/day, i.p.) or 10 mg/kg/day of memantine (i.p.) for 14 days four days prior to an LPS (5 mg/kg, i.p.) injection. Locomotor activity and anxiety-like behaviour were assessed using the open-field test (OFT). The phosphorylated tau protein level was measured using ELISA, while the expression and density of brain-derived neurotrophic factor (BDNF) and cAMP response element-binding (CREB) protein in the medial prefrontal cortex (mPFC) were measured using immunohistochemistry and Western blot, respectively. Minocycline treatment reduced locomotor deficits and anxiety-like behaviour associated with reduced phosphorylated tau protein levels, but it upregulated BDNF/CREB protein expressions in the mPFC in a comparable manner to memantine, with a higher dose of minocycline having better benefits. Minocycline treatment attenuated LPS-induced locomotor deficits and anxiety-like behaviour in rats and decreased phosphorylated tau protein levels, but it increased the expressions of the BDNF/CREB proteins in the mPFC.
    Matched MeSH terms: Lipopolysaccharides/pharmacology
  6. Sangaran PG, Ibrahim ZA, Chik Z, Mohamed Z, Ahmadiani A
    Mol Neurobiol, 2021 May;58(5):2407-2422.
    PMID: 33421016 DOI: 10.1007/s12035-020-02227-3
    Neuroinflammation, an inflammatory response within the nervous system, has been shown to be implicated in the progression of various neurodegenerative diseases. Recent in vivo studies showed that lipopolysaccharide (LPS) preconditioning provides neuroprotection by activating Toll-like receptor 4 (TLR4), one of the members for pattern recognition receptor (PRR) family that play critical role in host response to tissue injury, infection, and inflammation. Pre-exposure to low dose of LPS could confer a protective state against cellular apoptosis following subsequent stimulation with LPS at higher concentration, suggesting a role for TLR4 pre-activation in the signaling pathway of LPS-induced neuroprotection. However, the precise molecular mechanism associated with this protective effect is not well understood. In this article, we provide an overall review of the current state of our knowledge about LPS preconditioning in attenuating apoptosis mechanism and conferring neuroprotection via TLR4 signaling pathway.
    Matched MeSH terms: Lipopolysaccharides/pharmacology*
  7. Bindal P, Bindal U, Lin CW, Kasim NHA, Ramasamy TSAP, Dabbagh A, et al.
    Technol Health Care, 2017 Dec 04;25(6):1041-1051.
    PMID: 28800347 DOI: 10.3233/THC-170922
    Dental stem cells isolated for human dental pulp are an excellent source for regenerative medicine and dentistry. Simulation of clinical scenario is one of the crucial challenges for evaluation of the efficacy of DPSCs in various regenerative therapies. In this study we evaluated the viability of DPSCs after treatment with artificial bacterial lipopolysaccharides (LPS) as the main component responsible for inducing inflammatory response in majority of the inflammatory conditions in clinical scenario. Although a number of studies have previously treated stem cells with LPS from bacteria, however the accuracy level of the outcome was not established. Here we have analyzed the outcome using adaptive neuro-fuzzy inferences system (ANFIS) to predict the viability of human DPSCs after treatment with bacterial LPS.
    Matched MeSH terms: Lipopolysaccharides/pharmacology*
  8. Pang KL, Chin KY, Nirwana SI
    PMID: 36597600 DOI: 10.2174/1871530323666230103153134
    BACKGROUND: The immunomodulatory effects of plants have been utilised to enhance the immunity of humans against infections. However, evidence of such effects of agarwood leaves is very limited despite the long tradition of consuming the leaves as tea.

    OBJECTIVE: This study aimed to investigate the immuno-modulatory effects of agarwood leaf extract (ALE) derived from Aquilaria malaccensis using RAW264.7 murine macrophages.

    METHODS: In this study, RAW264.7 macrophages were incubated with ALE alone for 26 hours or ALE for 2 hours, followed by bacterial lipopolysaccharide for 24 hours. The nitrite and cytokine production (tumour necrosis factor-alpha (TNFα), interleukin (IL)-1β, IL-6, and IL-10), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX2) expression in the macrophages were assayed.

    RESULTS: The study showed that ALE alone was immunostimulatory on the macrophages by increasing the nitrite, TNFα, and IL-6 production and COX2 expression (p<0.05 vs. untreated unstimulated cells). Pre-treatment of ALE suppressed nitrite level and iNOS expression but enhanced TNFα and IL-6 production and COX2 expression (p<0.05 vs. untreated lipopolysaccharides (LPS)-stimulated cells). ALE also increased IL-10 production regardless of LPS stimulation (p<0.05 vs. untreated cells).

    CONCLUSION: ALE was able to promote the immune response of macrophages by upregulating pro-inflammatory cytokine levels and COX2 expression. It also regulated the extent of the inflammation by reducing iNOS expression and increasing IL-10 levels. Thus, ALE may have a role in enhancing the innate immune system against infection; however, its validation from in vivo studies is still pending.

    Matched MeSH terms: Lipopolysaccharides/pharmacology
  9. Hasan MM, Madhavan P, Ahmad Noruddin NA, Lau WK, Ahmed QU, Arya A, et al.
    Pharm Biol, 2023 Dec;61(1):1135-1151.
    PMID: 37497554 DOI: 10.1080/13880209.2023.2230251
    CONTEXT: Arjunolic acid (AA) is a triterpenoid saponin found in Terminalia arjuna (Roxb.) Wight & Arn. (Combretaceae). It exerts cardiovascular protective effects as a phytomedicine. However, it is unclear how AA exerts the effects at the molecular level.

    OBJECTIVE: This study investigates the cardioprotective effects of arjunolic acid (AA) via MyD88-dependant TLR4 downstream signaling marker expression.

    MATERIALS AND METHODS: The MTT viability assay was used to assess the cytotoxicity of AA. LPS induced in vitro cardiovascular disease model was developed in H9C2 and C2C12 myotubes. The treatment groups were designed such as control (untreated), LPS control, positive control (LPS + pyrrolidine dithiocarbamate (PDTC)-25 µM), and treatment groups were co-treated with LPS and three concentrations of AA (50, 75, and 100 µM) for 24 h. The changes in the expression of TLR4 downstream signaling markers were evaluated through High Content Screening (HCS) and Western Blot (WB) analysis.

    RESULTS: After 24 h of co-treatment, the expression of TLR4, MyD88, MAPK, JNK, and NF-κB markers were upregulated significantly (2-6 times) in the LPS-treated groups compared to the untreated control in both HCS and WB experiments. Evidently, the HCS analysis revealed that MyD88, NF-κB, p38, and JNK were significantly downregulated in the H9C2 myotube in the AA treated groups. In HCS, the expression of NF-κB was downregulated in C2C12. Additionally, TLR4 expression was downregulated in both H9C2 and C2C12 myotubes in the WB experiment.

    DISCUSSION AND CONCLUSIONS: TLR4 marker expression in H9C2 and C2C12 myotubes was subsequently decreased by AA treatment, suggesting possible cardioprotective effects of AA.

    Matched MeSH terms: Lipopolysaccharides/pharmacology
  10. Dewi IP, Dachriyanus, Aldi Y, Ismail NH, Hefni D, Susanti M, et al.
    J Ethnopharmacol, 2024 Feb 10;320:117381.
    PMID: 37967776 DOI: 10.1016/j.jep.2023.117381
    ETHNOPHARMACOLOGICAL RELEVANCE: Garcinia cowa Roxb. is called asam kandis in West Sumatra. This plant contains several quinone compounds, including tetraprenyltoluquinone (TPTQ). The bioactivity of this compound has been tested as an anticancer agent. However, reports regarding its anti-inflammatory effects are still limited, especially against coronavirus disease (Covid-19).

    AIM OF THE STUDY: This study explores the anti-inflammatory effect of TPTQ in silico, in vitro, and in vivo.

    MATERIALS AND METHODS: In silico testing used the Gnina application, opened via Google Colab. The TPTQ structure was docked with the nuclear factor kappa B (NF-ĸB) protein (PDB: 2RAM). In vitro testing began with testing the cytotoxicity of TPTQ against Raw 264.7 cells, using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) method. A phagocytic activity test was carried out using the neutral red uptake method, and interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) secretion tests were carried out using the enzyme-linked immunosorbent assay (ELISA) method. In vivo, tests were carried out on mice by determining cluster of differentiation 8+ (CD8+), natural killer cell (NK cell), and IL-6 parameters, using the ELISA method.

    RESULTS: TPTQ has a lower binding energy than the native ligand and occupies the same active site as the native ligand. TPTQ decreased the phagocytosis index and secretion of IL-6 and TNF-α experimentally in vitro. TPTQ showed significant downregulation of CD8+ and slightly decreased NK cells and IL-6 secretion in vivo.

    CONCLUSION: The potent inhibitory effect of TPTQ on the immune response suggests that TPTQ can be developed as an anti-inflammatory agent, especially in the treatment of Covid-19.

    Matched MeSH terms: Lipopolysaccharides/pharmacology
  11. Lian J, Zhu X, Du J, Huang B, Zhao F, Ma C, et al.
    Mol Ther, 2023 May 03;31(5):1365-1382.
    PMID: 36733250 DOI: 10.1016/j.ymthe.2023.01.025
    Mesenchymal stem cells regulate remote intercellular signaling communication via their secreted extracellular vesicles. Here, we report that menstrual blood-derived stem cells alleviate acute lung inflammation and injury via their extracellular vesicle-transmitted miR-671-5p. Disruption of this abundantly expressed miR-671-5p dramatically reduced the ameliorative effect of extracellular vesicles released by menstrual blood-derived stem cells on lipopolysaccharide (LPS)-induced pulmonary inflammatory injury. Mechanistically, miR-671-5p directly targets the kinase AAK1 for post-transcriptional degradation. AAK1 is found to positively regulate the activation of nuclear factor κB (NF-κB) signaling by controlling the stability of the inhibitory protein IκBα. This study identifies a potential molecular basis of how extracellular vesicles derived from mesenchymal stem cells improve pulmonary inflammatory injury and highlights the functional importance of the miR-671-5p/AAK1 axis in the progression of pulmonary inflammatory diseases. More importantly, this study provides a promising cell-based approach for the treatment of pulmonary inflammatory disorders through an extracellular vesicle-dependent pathway.
    Matched MeSH terms: Lipopolysaccharides/pharmacology
  12. Susanto H, Sudiana K, Nandika D, Karlinasari L, Arinana A, Karim SA, et al.
    Open Vet J, 2024 Sep;14(9):2269-2279.
    PMID: 39553755 DOI: 10.5455/OVJ.2024.v14.i9.15
    BACKGROUND: The fungus comb is a unique structure inside termites' nests that facilitates the growth of Termitomyces sp. as a nutrient source for the termites. It is known to possess immunomodulatory properties that boost the immune system.

    AIM: The objective of this study was to assess the impact of ethyl acetate extract of fungus comb (EAEFC) on the inflammatory reaction in the spleen of mice induced by intraperitoneal injection of lipopolysaccharide (LPS).

    METHODS: An experimental study was conducted using a post-test-only control group design with male BALB/C mice (n = 24). The mice were divided randomly into four groups, each comprising six mice, and administered substances via gavage. Groups I and III were administered a solution of 5% dimethyl sulfoxide (DMSO) in distilled water, while Groups II and IV were given 500 mg/kg BW EAEFC dissolved in 5% DMSO. On the fifteenth day, Groups I and II received intraperitoneal injections of 5 ml/kg BW saline, while Groups III and IV were injected with 10 mg/kg BW LPS dissolved in saline. After three hours, the mice were euthanized and splenic immunohistology was examined under a light microscope. The results were expressed as mean ± standard deviation, while the group differences were assessed statistically.

    RESULTS: The expression of interleukin (IL)-1, furin, and activated NK cell was significantly higher in the inflamed model after EAEFC supplementation, while the extract suppressed IL-10.

    CONCLUSION: EAEFC was found to alter cytokine expression in the spleen in response to inflammation.

    Matched MeSH terms: Lipopolysaccharides/pharmacology
  13. Salim E, Kumolosasi E, Jantan I
    J Nat Med, 2014 Jul;68(3):647-53.
    PMID: 24799081 DOI: 10.1007/s11418-014-0841-0
    The inhibitory activities of the methanol extracts from 20 selected medicinal plants on the release of pro-inflammatory cytokines in human peripheral blood mononuclear cells (PBMCs) were evaluated. The major compound from the most active plant extract was also investigated. The inhibitory effect of the methanol extracts on the release of pro-inflammatory cytokines was tested by incubating PBMCs with the sample and then stimulating by lipopolysaccharide at 0.1 μg/ml. The level of cytokines was determined using enzyme-linked immunosorbent assay. Among the extracts tested, Andrographis paniculata extract demonstrated the strongest inhibition of interleukin (IL)-1β, IL-1α, and IL-6 release, with IC50 values of 1.54, 1.06, and 0.74 μg/ml, respectively. The IC50 value of A. paniculata extract was significantly higher than that of andrographolide on IL-1α, IL-1β, and IL-6 (p 
    Matched MeSH terms: Lipopolysaccharides/pharmacology
  14. Najmuldeen IA, Hadi AH, Awang K, Mohamad K, Ketuly KA, Mukhtar MR, et al.
    J Nat Prod, 2011 May 27;74(5):1313-7.
    PMID: 21428417 DOI: 10.1021/np200013g
    Three new limonoids, chisomicines A-C (1-3), have been isolated from the bark of Chisocheton ceramicus. Their structures were determined by 2D NMR, CD spectroscopic methods, and X-ray analysis. Chisomicine A (1) exhibited NO production inhibitory activity in J774.1 cells stimulated by LPS dose-dependently at high cell viability.
    Matched MeSH terms: Lipopolysaccharides/pharmacology
  15. Vidyadaran S, Ooi YY, Subramaiam H, Badiei A, Abdullah M, Ramasamy R, et al.
    Cell Immunol, 2009;259(1):105-10.
    PMID: 19577228 DOI: 10.1016/j.cellimm.2009.06.005
    A challenge for studies involving microglia cultures is obtaining sufficient cells for downstream experiments. Macrophage colony-stimulating factor (M-CSF) has been used to improve yield of microglia in culture. However, the effects of M-CSF on activation profiles of microglia cultures are still unclear. Microglia activation is characterised by upregulation of co-stimulatory molecules and an inflammatory phenotype. The aim of this study is to demonstrate whether M-CSF supplementation alters microglial responses in resting and activated conditions. Microglia derived from mixed glia cultures and the BV-2 microglia cell line were cultivated with/without M-CSF and activated with lipopolysaccharide (LPS) and beta amyloid (Abeta). We show M-CSF expands primary microglia without affecting microglial responses to LPS and Abeta, as shown by the comparable expression of MHC class II and CD40 to microglia grown without this growth factor. M-CSF supplementation in BV-2 cells had no effect on nitric oxide (NO) production. Therefore, M-CSF can be considered for improving microglia yield in culture without introducing activation artefacts.
    Matched MeSH terms: Lipopolysaccharides/pharmacology*
  16. Loh LC, Lo WH, Kanabar V, O'Connor BJ
    Asian Pac J Allergy Immunol, 2006 Jun-Sep;24(2-3):153-60.
    PMID: 17136881
    To study the nature of endotoxin or lipopolysaccharide (LPS) induced inflammation, we developed a method of quantifying intracellular human neutrophil elastase (HNE) in lysed sputum polymorphs as a means to study the degranulation status of LPS-recruited neutrophils. Induced sputum, blood and exhaled nitric oxide (NO) were collected from 10 healthy non-atopic human subjects after inhaling a single 15 microg dose of Escherichia coil LPS in an open study. At 6 hours, LPS inhalation caused significant increase of sputum and blood neutrophils but without parallel increase in myeloperoxidase, HNE or interleukin-8 (IL-8) in sputum sol and blood, or exhaled NO. Intracellular HNE in lysed sputum polymorphs or purified blood neutrophils did not show any significant changes between inhaled LPS and saline, nor was there any appreciable change in percentage HNE release induced by N-Formyl-Met-Leu-Phe (fMLP) in vitro. We concluded that in healthy humans, the transient neutrophilic inflammation induced by a single dose of inhaled 15 microg LPS is mainly characterized by cell recruitment, not enhanced secretion of granular mediators or increased exhaled NO based on our experimental conditions.
    Matched MeSH terms: Lipopolysaccharides/pharmacology
  17. Lew LC, Liong MT
    J Appl Microbiol, 2013 May;114(5):1241-53.
    PMID: 23311666 DOI: 10.1111/jam.12137
    Probiotics have been extensively reviewed for decades, emphasizing on improving general gut health. Recently, more studies showed that probiotics may exert other health-promoting effects beyond gut well-being, attributed to the rise of the gut-brain axis correlations. Some of these new benefits include skin health such as improving atopic eczema, atopic dermatitis, healing of burn and scars, skin-rejuvenating properties and improving skin innate immunity. Increasing evidence has also showed that bacterial compounds such as cell wall fragments, their metabolites and dead bacteria can elicit certain immune responses on the skin and improve skin barrier functions. This review aimed to underline the mechanisms or the exact compounds underlying the benefits of bacterial extract on the skin based on evidences from in vivo and in vitro studies. This review could be of help in screening of probiotic strains with potential dermal enhancing properties for topical applications.
    Matched MeSH terms: Lipopolysaccharides/pharmacology
  18. Fazalul Rahiman SS, Morgan M, Gray P, Shaw PN, Cabot PJ
    PLoS One, 2016;11(4):e0153005.
    PMID: 27055013 DOI: 10.1371/journal.pone.0153005
    Dynorphin 1-17, (DYN 1-17) opioid peptide produces antinociception following binding to the kappa-opioid peptide (KOP) receptor. Upon synthesis and release in inflamed tissues by immune cells, DYN 1-17 undergoes rapid biotransformation and yields a unique set of opioid and non-opioid fragments. Some of these major fragments possess a role in immunomodulation, suggesting that opioid-targeted therapeutics may be effective in diminishing the severity of inflammatory disorders. This study aimed to examine the immunomodulatory effects of DYN 1-17 and major N-terminal fragments found in the inflammatory environment on nuclear factor-kappaB/p65 (NF-κB/p65) nuclear translocation and the release of interleukin-1beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) from lipopolysaccharide (LPS)-stimulated, differentiated THP-1 cells. The results demonstrate that NF-κB/p65 nuclear translocation was significantly attenuated following treatment with DYN 1-17 and a specific range of fragments, with the greatest reduction observed with DYN 1-7 at a low concentration (10 nM). Antagonism with a selective KOP receptor antagonist, ML-190, significantly reversed the inhibitory effects of DYN 1-17, DYN 1-6, DYN 1-7 and DYN 1-9, but not other DYN 1-17 N-terminal fragments (DYN 1-10 and 1-11) on NF-κB/p65 nuclear translocation. DYN 1-17 and selected fragments demonstrated differential modulation on the release of IL-1β and TNF-α with significant inhibition observed with DYN 1-7 at low concentrations (1 nM and 10 pM). These effects were blocked by ML-190, suggesting a KOP receptor-mediated pathway. The results demonstrate that DYN 1-17 and certain N-terminal fragments, produced in an inflamed environment, play an anti-inflammatory role by inhibiting NF-κB/p65 translocation and the subsequent cytokine release through KOP receptor-dependent and independent pathways.
    Matched MeSH terms: Lipopolysaccharides/pharmacology*
  19. Ooi TC, Chan KM, Sharif R
    Biol Trace Elem Res, 2016 Aug;172(2):458-464.
    PMID: 26749414 DOI: 10.1007/s12011-015-0615-x
    This study aimed to investigate the role of the mitogen-activated protein kinases (MAPKs) signaling pathway in the anti-inflammatory effects of zinc carnosine (ZnC) in lipopolysaccharide (LPS)-induced RAW 264.7 cells. Cells were pretreated with ZnC (0-100 μM) for 2 h prior to the addition of LPS (1 μg/ml). Following 24 h of treatment, ZnC was found not to be cytotoxic to RAW 264.7 cells up to the concentration of 100 μM. Our current findings showed that ZnC did not protect RAW 264.7 cells from LPS-induced "respiratory burst". Significant increment in intracellular glutathione (GSH) level and reduction in thiobarbituric acid reactive substances (TBARS) concentration can only be observed in cell pretreated with high doses of ZnC only (50 and 100 μM for GSH and 100 μM only for TBARS). On the other hand, pretreatment of cells with ZnC was able to inhibit LPS-induced inducible nitric oxide synthase and cyclooxygenase-2 expression significantly. Furthermore, results from immunoblotting showed that ZnC was able to suppress nuclear factor-kappaB (NF-κB) activation, and highest suppression can be observed at 100 μM of ZnC pretreatment. However, pretreatment of ZnC did not inhibit the early activation of MAPKs. In conclusion, pretreatment with ZnC was able to inhibit the expression of inflammatory mediators in LPS-induced RAW 264.7 cells, mainly via suppression of NF-κB activation, and is independent of the MAPKs signaling pathway.
    Matched MeSH terms: Lipopolysaccharides/pharmacology
  20. Phan CS, Ng SY, Kim EA, Jeon YJ, Palaniveloo K, Vairappan CS
    Mar Drugs, 2015 May;13(5):3103-15.
    PMID: 25996100 DOI: 10.3390/md13053103
    Two new bicyclogermacrenes, capgermacrenes A (1) and B (2), were isolated with two known compounds, palustrol (3) and litseagermacrane (4), from a population of Bornean soft coral Capnella sp. The structures of these metabolites were elucidated based on spectroscopic data. Compound 1 was found to inhibit the accumulation of the LPS-induced pro-inflammatory IL-1b and NO production by down-regulating the expression of iNOS protein in RAW 264.7 macrophages.
    Matched MeSH terms: Lipopolysaccharides/pharmacology
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