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  1. Fulltext (+)-Kunstlerone, a new antioxidant neolignan from the Leaves of Beilschmiedia kunstleri gamble
    Mollataghi A, Hadi AH, Awang K, Mohamad J, Litaudon M, Mukhtar MR
    Molecules, 2011 Aug 04;16(8):6582-90.
    PMID: 21818061 DOI: 10.3390/molecules16086582
    A new neolignan, 3,4-dimethoxy-3',4'-methylenedioxy-2,9-epoxy-6,7-cyclo-1,8-neolign-11-en-5(5H)-one, which has been named (+)-kunstlerone (1), together with six known alkaloids: (+)-norboldine (2), (+)-N-methylisococlaurine (3), (+)-cassythicine (4), (+)-laurotetanine (5), (+)-boldine (6) and (-)-pallidine (7), were isolated from the leaves of Beilschmiedia kunstleri. The structures were established through various spectroscopic methods notably 1D- and 2D-NMR, UV, IR and LCMS-IT-TOF. (+)- Kunstlerone (1) showed a strong antioxidant activity, with an SC(50) of 20.0 µg/mL.
    Matched MeSH terms: Biphenyl Compounds/antagonists & inhibitors; Free Radicals/antagonists & inhibitors; Picrates/antagonists & inhibitors
  2. Fulltext (R)-(+)-α-lipoic acid protected NG108-15 cells against H₂O₂-induced cell death through PI3K-Akt/GSK-3β pathway and suppression of NF-κβ-cytokines
    Kamarudin MN, Mohd Raflee NA, Hussein SS, Lo JY, Supriady H, Abdul Kadir H
    Drug Des Devel Ther, 2014;8:1765-80.
    PMID: 25336920 DOI: 10.2147/DDDT.S67980
    Alpha-lipoic acid, a potent antioxidant with multifarious pharmacological benefits has been reported to be neuroprotective in several neuronal models and used to treat neurological disorders such as Alzheimer's disease. Nonetheless, conclusive mechanisms of alpha-lipoic acid for its protective effects particularly in NG108-15 cells have never been investigated. In this study, the intricate neuroprotective molecular mechanisms by (R)-(+)-alpha-lipoic acid (R-LA) against H2O2-induced cell death in an in vitro model of neurodegeneration were elucidated. Pretreatment with R-LA (2 hours) significantly increased NG108-15 cell viability as compared to H2O2-treated cells and mitigated the induction of apoptosis as evidenced by Hoechst 33342/propidium iodide staining. R-LA (12.5-50 μM) aggrandized the reduced glutathione over glutathione disulfide ratio followed by a reduction in the intracellular reactive oxygen species level and an increase in mitochondrial membrane potential following H2O2 exposure. Moreover, pretreatment with R-LA stimulated the activation of PI3K-Akt through mTORC1 and mTORC2 components (mTOR, rictor and raptor) and production of antiinflammatory cytokine, IL-10 which led to the inactivation of glycogen synthase kinase-3β (GSK-3β) and reduction of both Bax/Bcl2 and Bax/Bcl-xL ratios, accompanied by inhibition of the cleaved caspase-3. Additionally, this observation was preceded by the suppression of NF-κβ p65 translocation and production of proinflammatory cytokines (IL-6 and TNF-α). The current findings accentuate new mechanistic insight of R-LA against apoptogenic and brain inflammatory factors in a neuronal model. These results further advocate the therapeutic potential of R-LA for the treatment of neurodegenerative diseases.
    Matched MeSH terms: Hydrogen Peroxide/antagonists & inhibitors*; Cytokines/antagonists & inhibitors*; NF-kappa B/antagonists & inhibitors*
  3. 1 H-NMR metabolomics for evaluating the protective effect of Clinacanthus nutans (Burm. f) Lindau water extract against nitric oxide production in LPS-IFN-γ activated RAW 264.7 macrophages
    Khoo LW, Kow ASF, Maulidiani M, Ang MY, Chew WY, Lee MT, et al.
    Phytochem Anal, 2019 Jan;30(1):46-61.
    PMID: 30183131 DOI: 10.1002/pca.2789
    INTRODUCTION: Clinacanthus nutans, a small shrub that is native to Southeast Asia, is commonly used in traditional herbal medicine and as a food source. Its anti-inflammation properties is influenced by the metabolites composition, which can be determined by different binary extraction solvent ratio and extraction methods used during plant post-harvesting stage.

    OBJECTIVE: Evaluate the relationship between the chemical composition of C. nutans and its anti-inflammatory properties using nuclear magnetic resonance (NMR) metabolomics approach.

    METHODOLOGY: The anti-inflammatory effect of C. nutans air-dried leaves extracted using five different binary extraction solvent ratio and two extraction methods was determined based on their nitric oxide (NO) inhibition effect in lipopolysaccharide-interferon-gamma (LPS-IFN-γ) activated RAW 264.7 macrophages. The relationship between extract bioactivity and metabolite profiles and quantifications were established using 1 H-NMR metabolomics and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The possible metabolite biosynthesis pathway was constructed to further strengthen the findings.

    RESULTS: Water and sonication prepared air-dried leaves possessed the highest NO inhibition activity (IC50  = 190.43 ± 12.26 μg/mL, P 

    Matched MeSH terms: Nitric Oxide/antagonists & inhibitors
  4. 1'S-1'-acetoxyeugenol acetate: a novel phenylpropanoid from Alpinia conchigera enhances the apoptotic effects of paclitaxel in MCF-7 cells through NF-κB inactivation
    In LL, Azmi MN, Ibrahim H, Awang K, Nagoor NH
    Anticancer Drugs, 2011 Jun;22(5):424-34.
    PMID: 21346553 DOI: 10.1097/CAD.0b013e328343cbe6
    In this study, the apoptotic mechanism and combinatorial chemotherapeutic effects of the cytotoxic phenylpropanoid compound 1'S-1'-acetoxyeugenol acetate (AEA), extracted from rhizomes of the Malaysian ethnomedicinal plant Alpinia conchigera Griff. (Zingiberaceae), on MCF-7 human breast cancer cells were investigated for the first time. Data from cytotoxic and apoptotic assays such as live and dead and poly-(ADP-ribose) polymerase cleavage assays indicated that AEA was able to induce apoptosis in MCF-7 cells, but not in normal human mammary epithelial cells. A microarray global gene expression analysis of MCF-7 cells, treated with AEA, suggested that the induction of tumor cell death through apoptosis was modulated through dysregulation of the nuclear factor-kappaB (NF-κB) pathway, as shown by the reduced expression of various κB-regulated gene targets. Consequent to this, western blot analysis of proteins corresponding to the NF-κB pathway indicated that AEA inhibited phosphorylation levels of the inhibitor of κB-kinase complex, resulting in the elimination of apoptotic resistance originating from NF-κB activation. This AEA-based apoptotic modulation was elucidated for the first time in this study, and gave rise to the proposal of an NF-κB model termed the 'Switching/Alternating Model.' In addition to this, AEA was also found to synergistically enhance the proapoptotic effects of paclitaxel, when used in combination with MCF-7 cells, presumably by a chemosensitizing role. Therefore, it was concluded that AEA isolated from the Malaysian tropical ginger (A. conchigera) served as a very promising candidate for further in-vivo development in animal models and in subsequent clinical trials involving patients with breast-related malignancies.
    Matched MeSH terms: NF-kappa B/antagonists & inhibitors*; I-kappa B Kinase/antagonists & inhibitors
  5. 2'-Aryl and 4'-arylidene substituted pyrazolones: As potential α-amylase inhibitors
    Yousuf S, Khan KM, Salar U, Chigurupati S, Muhammad MT, Wadood A, et al.
    Eur J Med Chem, 2018 Nov 05;159:47-58.
    PMID: 30268823 DOI: 10.1016/j.ejmech.2018.09.052
    Acarbose and voglibose are well-known α-amylase inhibitors used for the management of type-II diabetes mellitus. Unfortunately, these well-known and clinically used inhibitors are also associated with several adverse effects. Therefore, there is still need to develop the safer therapy. Despite of a broad spectrum of biological significances of pyrazolone, it is infrequently evaluated for α-amylase inhibition. Current study deals with the synthesis and biological screening of aryl and arylidene substituted pyrazolones 1-18 for their potential α-amylase inhibitory activity. Structures of synthetic derivatives 1-18 were identified by different spectroscopic techniques. All compounds 1-18 (IC50 = 1.61 ± 0.16 μM to 2.38 ± 0.09 μM) exhibited significant to moderate inhibitory potential when compared to standard acarbose (IC50 = 1.46 ± 0.26 μM). A number of derivatives including 8-12 (IC50 = 1.68 ± 0.1 μM to 1.97 ± 0.07 μM) and 14-16 (IC50 = 1.61 ± 0.16 μM to 1.93 ± 0.07 μM) were found to be significantly active. Limited SAR suggested that different substitutions on compounds do not have any significant effect on the inhibitory potential. Compounds were found to be mixed-type inhibitors revealed by kinetic studies. However, in silico study was identified a number of key features participating in the interaction with the binding site of α-amylase enzyme.
    Matched MeSH terms: alpha-Amylases/antagonists & inhibitors*
  6. 2-Aryl benzimidazoles: Synthesis, In vitro α-amylase inhibitory activity, and molecular docking study
    Adegboye AA, Khan KM, Salar U, Aboaba SA, Kanwal, Chigurupati S, et al.
    Eur J Med Chem, 2018 Apr 25;150:248-260.
    PMID: 29533872 DOI: 10.1016/j.ejmech.2018.03.011
    Despite of many diverse biological activities exhibited by benzimidazole scaffold, it is rarely explored for the α-amylase inhibitory activity. For that purpose, 2-aryl benzimidazole derivatives 1-45 were synthesized and screened for in vitro α-amylase inhibitory activity. Structures of all synthetic compounds were deduced by various spectroscopic techniques. All compounds revealed inhibition potential with IC50 values of 1.48 ± 0.38-2.99 ± 0.14 μM, when compared to the standard acarbose (IC50 = 1.46 ± 0.26 μM). Limited SAR suggested that the variation in the inhibitory activities of the compounds are the result of different substitutions on aryl ring. In order to rationalize the binding interactions of most active compounds with the active site of α-amylase enzyme, in silico study was conducted.
    Matched MeSH terms: alpha-Amylases/antagonists & inhibitors*
  7. 3,4-Dimethoxybenzohydrazide derivatives as antiulcer: Molecular modeling and density functional studies
    Taha M, Ismail NH, Zaki HM, Wadood A, Anouar EH, Imran S, et al.
    Bioorg Chem, 2017 12;75:235-241.
    PMID: 29031169 DOI: 10.1016/j.bioorg.2017.10.004
    3,4-Dimethoxybenzohydrazide derivatives (1-25) have been synthesized and evaluated for their urease inhibitory potential. Among the series, compounds 2, 3, 4 and 5 with IC50 values 12.61 ± 0.07, 18.24 ± 0.14, 19.22 ± 0.21, and 8.40 ± 0.05 µM, respectively, showed excellent urease inhibitory potentials when compared with standard thiourea (IC50 value 21.40 ± 0.21 µM). Compounds 1, 6, 8, 18, 19 and 20 also showed good to moderate inhibition, while the remaining compounds were found to be completely inactive. The structures of compounds 6 and 25 were confirmed through X-ray crystallography while the structures of remaining compounds were confirmed through ESI-MS and 1H NMR. Molecular docking studies were performed understand the binding interactions with enzyme active site. The synthesized compounds were evaluated for cytotoxicity and found to be nontoxic.
    Matched MeSH terms: Urease/antagonists & inhibitors*
  8. 5-Bromo-2-aryl benzimidazole derivatives as non-cytotoxic potential dual inhibitors of α-glucosidase and urease enzymes
    Arshad T, Khan KM, Rasool N, Salar U, Hussain S, Asghar H, et al.
    Bioorg Chem, 2017 06;72:21-31.
    PMID: 28346872 DOI: 10.1016/j.bioorg.2017.03.007
    On the basis of previous report on promising α-glucosidase inhibitory activity of 5-bromo-2-aryl benzimidazole derivatives, these derivatives were further screened for urease inhibitory and cytotoxicity activity in order to get more potent and non-cytotoxic potential dual inhibitor for the patients suffering from diabetes as well as peptic ulcer. In this study, all compounds showed varying degree of potency in the range of (IC50=8.15±0.03-354.67±0.19μM) as compared to standard thiourea (IC50=21.25±0.15μM). It is worth mentioning that derivatives 7 (IC50=12.07±0.05μM), 8 (IC50=10.57±0.12μM), 11 (IC50=13.76±0.02μM), 14 (IC50=15.70±0.12μM) and 22 (IC50=8.15±0.03μM) were found to be more potent inhibitors than standard. All compounds were also evaluated for cytotoxicity towards 3T3 mouse fibroblast cell line and found to be completely non-toxic. Previously benzimidazole 1-25 were also showed α-glucosidase inhibitory potential. In silico studies were performed on the lead molecules i.e.2, 7, 8, 11, 14, and 22, in order to rationalize the binding interaction of compounds with the active site of urease enzyme.
    Matched MeSH terms: Urease/antagonists & inhibitors*
  9. A Dimeric sesquiterpenoid from a Malaysian Meiogyne as a new inhibitor of Bcl-xL/BakBH3 domain peptide interaction
    Litaudon M, Bousserouel H, Awang K, Nosjean O, Martin MT, Dau ME, et al.
    J Nat Prod, 2009 Mar 27;72(3):480-3.
    PMID: 19161318 DOI: 10.1021/np8006292
    In an effort to find potent inhibitors of the antiapoptotic protein Bcl-xL, a systematic in vitro evaluation was undertaken on 1470 Malaysian plant extracts. The ethyl acetate extract obtained from the bark of Meiogyne cylindrocarpa was selected for its interaction with the Bcl-xL/Bak association. Bioassay-guided purification of this species led to the isolation of two new dimeric sesquiterpenoids (1 and 2) possessing an unprecedented substituted cis-decalin carbon skeleton. Meiogynin A (1) showed the strongest activity with a K(i) of 10.8 +/- 3.1 microM.
    Matched MeSH terms: Proto-Oncogene Proteins c-bcl-2/antagonists & inhibitors*
  10. Fulltext A Kinetic Approach of DPPH Free Radical Assay of Ferulate-Based Protic Ionic Liquids (PILs)
    Ahmad NA, Jumbri K, Ramli A, Abd Ghani N, Ahmad H, Lim JW
    Molecules, 2018 Dec 05;23(12).
    PMID: 30563037 DOI: 10.3390/molecules23123201
    The antiradical efficiency (AE) and kinetic behavior of a new ferulate-based protic ionic liquids (PILs) were described using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. The reduction of the DPPH free radical (DPPH•) was investigated by measuring the decrease in absorbance at 517 nm. The time to reach steady state for the reaction of parent acid (ferulic acid) and synthesized PILs with DPPH• was continuously recorded for 1 h. Results revealed that the AE of 2-butylaminoethanol ferulate (2BAEF), 3-dimethylaminopropanol ferulate (3DMAPF) and 3-diethylaminopropanol ferulate (3DEAPF) PILs have improved compared to ferulic acid (FA) as the reaction class changes from low to medium. This attributed to the strong hydrogen abstraction occurred in the PILs. Furthermore, these PILs were found to have a good kinetic behavior compared to FA due to the high rate constant (k₂) (164.17, 242.84 and 244.73 M-1 s-1, respectively). The alkyl chain length and more alkyl substituents on the nitrogen atom of cation were believed to reduce the cation-anion interaction and speed up the hydrogen atom transfer (HAT) and electron transfer (ET) mechanisms; hence, increased rate constant was observed leading to a strong antioxidant activity of the synthesized PILs.
    Matched MeSH terms: Biphenyl Compounds/antagonists & inhibitors; Picrates/antagonists & inhibitors
  11. Fulltext A Pharmacological Examination of the Cardiovascular Effects of Malayan Krait (Bungarus candidus) Venoms
    Chaisakul J, Rusmili MR, Hodgson WC, Hatthachote P, Suwan K, Inchan A, et al.
    Toxins (Basel), 2017 03 29;9(4).
    PMID: 28353659 DOI: 10.3390/toxins9040122
    Cardiovascular effects (e.g., tachycardia, hypo- and/or hypertension) are often clinical outcomes of snake envenoming. Malayan krait (Bungarus candidus) envenoming has been reported to cause cardiovascular effects that may be related to abnormalities in parasympathetic activity. However, the exact mechanism for this effect has yet to be determined. In the present study, we investigated thein vivoandin vitrocardiovascular effects ofB. candidusvenoms from Southern (BC-S) and Northeastern (BC-NE) Thailand. SDS-PAGE analysis of venoms showed some differences in the protein profile of the venoms.B. candidusvenoms (50 µg/kg-100 µg/kg, i.v.) caused dose-dependent hypotension in anaesthetised rats. The highest dose caused sudden hypotension (phase I) followed by a return of mean arterial pressure to baseline levels and a decrease in heart rate with transient hypertension (phase II) prior to a small decrease in blood pressure (phase III). Prior administration of monovalent antivenom significantly attenuated the hypotension induced by venoms (100 µg/kg, i.v.). The sudden hypotensive effect of BC-NE venom was abolished by prior administration of hexamethonium (10 mg/kg, i.v.) or atropine (5 mg/kg, i.v.). BC-S and BC-NE venoms (0.1 µg/kg-100 µg/ml) induced concentration-dependent relaxation (EC50= 8 ± 1 and 13 ± 3 µg/mL, respectively) in endothelium-intact aorta. The concentration-response curves were markedly shifted to the right by pre-incubation with L-NAME (0.2 mM), or removal of the endothelium, suggesting that endothelium-derived nitric oxide (NO) is likely to be responsible for venom-induced aortic relaxation. Our data indicate that the cardiovascular effects caused byB. candidusvenoms may be due to a combination of vascular mediators (i.e., NO) and autonomic adaptation via nicotinic and muscarinic acetylcholine receptors.
    Matched MeSH terms: Nitric Oxide Synthase/antagonists & inhibitors
  12. A Randomized, Placebo-Controlled Phase 2 Trial of CNTO 6785 in Chronic Obstructive Pulmonary Disease
    Eich A, Urban V, Jutel M, Vlcek J, Shim JJ, Trofimov VI, et al.
    COPD, 2017 Oct;14(5):476-483.
    PMID: 28753067 DOI: 10.1080/15412555.2017.1335697
    Interleukin (IL)-17A may be an underlying factor in the pathophysiology of chronic obstructive pulmonary disease (COPD). Anti-IL-17 monoclonal antibodies have been used successfully in treating several immune-mediated inflammatory diseases. This phase 2, randomized, placebo-controlled, double-blind, parallel-group, proof-of-concept study is the first clinical study evaluating the efficacy and safety of the anti-IL-17A monoclonal antibody CNTO 6785 in patients with symptomatic moderate-to-severe COPD. Patients were treated with CNTO 6785 (n = 93) or placebo (n = 94) intravenously at Weeks 0, 2, and 4 (induction), then Weeks 8 and 12, and followed till Week 24. The primary efficacy endpoint was the change from baseline in pre-bronchodilator percent-predicted forced expiratory volume in 1 second at Week 16. Samples were collected at all visits for pharmacokinetic (PK) evaluation, and standard safety assessments were performed. The mean difference in the primary efficacy endpoint between CNTO 6785 and placebo was not statistically significant (-0.49%; p = 0.599). No other efficacy endpoints demonstrated clinically or statistically significant differences with CNTO 6785 compared with placebo. CNTO 6785 was generally well tolerated; no major safety signals were detected. The most frequently reported treatment-emergent adverse events were infections and infestations; however, no notable differences were observed between CNTO 6785 and placebo in terms of rates of infections. PK results suggested that the steady state of serum CNTO 6785 concentration was reached within 16 weeks. These results suggest that IL-17A is unlikely to be a dominant driver in the pathology of, or a viable therapeutic target for, COPD. ClinicalTrials.gov Identifier: NCT01966549; EudraCT Identifier: 2012-003607-36.
    Matched MeSH terms: Interleukin-17/antagonists & inhibitors*
  13. A molecular approach in drug development for Alzheimer's disease
    Agatonovic-Kustrin S, Kettle C, Morton DW
    Biomed Pharmacother, 2018 Oct;106:553-565.
    PMID: 29990843 DOI: 10.1016/j.biopha.2018.06.147
    An increase in dementia numbers and global trends in population aging across the world prompts the need for new medications to treat the complex biological dysfunctions, such as neurodegeneration associated with dementia. Alzheimer's disease (AD) is the most common form of dementia. Cholinergic signaling, which is important in cognition, is slowly lost in AD, so the first line therapy is to treat symptoms with acetylcholinesterase inhibitors to increase levels of acetylcholine. Out of five available FDA-approved AD medications, donepezil, galantamine and rivastigmine are cholinesterase inhibitors while memantine, a N-methyl d-aspartate (NMDA) receptor antagonist, blocks the effects of high glutamate levels. The fifth medication consists of a combination of donepezil and memantine. Although these medications can reduce and temporarily slow down the symptoms of AD, they cannot stop the damage to the brain from progressing. For a superior therapeutic effect, multi-target drugs are required. Thus, a Multi-Target-Directed Ligand (MTDL) strategy has received more attention by scientists who are attempting to develop hybrid molecules that simultaneously modulate multiple biological targets. This review highlights recent examples of the MTDL approach and fragment based strategy in the rational design of new potential AD medications.
    Matched MeSH terms: Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors; GPI-Linked Proteins/antagonists & inhibitors
  14. A novel single-domain peptide, anti-LPS factor from prawn: synthesis of peptide, antimicrobial properties and complete molecular characterization
    Arockiaraj J, Kumaresan V, Bhatt P, Palanisamy R, Gnanam AJ, Pasupuleti M, et al.
    Peptides, 2014 Mar;53:79-88.
    PMID: 24269604 DOI: 10.1016/j.peptides.2013.11.008
    In this study, we reported a complete molecular characterization including bioinformatics features, gene expression, peptide synthesis and its antimicrobial activities of an anti-lipopolysaccharide (LPS) factor (ALF) cDNA identified from the established cDNA library of freshwater prawn Macrobrachium rosenbergii (named as MrALF). The mature protein has an estimated molecular weight of 11.240 kDa with an isoelectric point of 9.46. The bioinformatics analysis showed that the MrALF contains an antimicrobial peptide (AMP) region between T54 and P77 with two conserved cysteine residues (Cys55 and Cys76) which have an anti-parallel β-sheet confirmation. The β-sheet is predicted as cationic with hydrophobic nature containing a net charge of +5. The depicted AMP region is determined to be amphipathic with a predicted hydrophobic face 'FPVFI'. A highest MrALF gene expression was observed in hemocytes and is up-regulated with virus [white spot syndrome baculovirus (WSBV)], bacteria (Aeromonas hydrophila) and Escherichia coli LPS at various time points. The LPS binding region of MrALF peptide was synthesized to study the antimicrobial property, bactericidal efficiency and hemolytic capacity. The peptide showed antimicrobial activity against both the Gram-negative and Gram-positive bacteria. The bactericidal assay showed that the peptide recognized the LPS of bacterial cell walls and binding on its substrate and thereby efficiently distinguishing the pathogens. The hemolytic activity of MrALF peptide is functioning in a concentration dependant manner. In summary, the comprehensive analysis of MrALF showed it to be an effective antimicrobial peptide and thus it plays a crucial role in the defense mechanism of M. rosenbergii.
    Matched MeSH terms: Lipopolysaccharides/antagonists & inhibitors*
  15. A pilot experiment for production of Malayan krait antivenom: immunization of rabbits with Bungarus candidus venom
    Chanhome L, Puempunpanich S, Omori-Satoh T, Chaiyabutr N, Sitprija V
    J Nat Toxins, 2002 Dec;11(4):353-6.
    PMID: 12503879
    Immunization with Bungarus candidus venom was performed in four rabbits at high dose (initial dose, 75 microg/kg) and low dose (initial dose, 50 microg/kg). Each dose group consisted of two rabbits; one rabbit received the venom subcutaneously (s.c.) and the other intradermally (i.d.). The venom was injected as emulsified solutions with the same volume of Freund's complete adjuvant until the 4th immunization, thereafter as plain solutions. By stepwise increments of the immunizing dose, the higher dose group received a dose of 200 microg/kg and the lower dose group 150 microg/kg after the 5th immunization, respectively. Thereafter, seven additional immunizations were performed within six months. All rabbits were sacrificed two weeks after the last immunization (12th). Antilethal activity of the immunized antisera thus obtained was determined not only with the homologous venom but also with two heterologous venoms from Bungarus fasciatus and Bungarus flaviceps. Immunodiffusion analysis was also performed with these venoms. The results obtained in this pilot trial provided useful information for production of Malayan krait antivenom at Queen Saovabha Memorial Institute.
    Matched MeSH terms: Elapid Venoms/antagonists & inhibitors*
  16. Fulltext A quaternary ammonium silane antimicrobial triggers bacterial membrane and biofilm destruction
    Daood U, Matinlinna JP, Pichika MR, Mak KK, Nagendrababu V, Fawzy AS
    Sci Rep, 2020 07 03;10(1):10970.
    PMID: 32620785 DOI: 10.1038/s41598-020-67616-z
    To study the antimicrobial effects of quaternary ammonium silane (QAS) exposure on Streptococcus mutans and Lactobacillus acidophilus bacterial biofilms at different concentrations. Streptococcus mutans and Lactobacillus acidophilus biofilms were cultured on dentine disks, and incubated for bacterial adhesion for 3-days. Disks were treated with disinfectant (experimental QAS or control) and returned to culture for four days. Small-molecule drug discovery-suite was used to analyze QAS/Sortase-A active site. Cleavage of a synthetic fluorescent peptide substrate, was used to analyze inhibition of Sortase-A. Raman spectroscopy was performed and biofilms stained for confocal laser scanning microscopy (CLSM). Dentine disks that contained treated dual-species biofilms were examined using scanning electron microscopy (SEM). Analysis of DAPI within biofilms was performed using CLSM. Fatty acids in bacterial membranes were assessed with succinic-dehydrogenase assay along with time-kill assay. Sortase-A protein underwent conformational change due to QAS molecule during simulation, showing fluctuating alpha and beta strands. Spectroscopy revealed low carbohydrate intensities in 1% and 2% QAS. SEM images demonstrated absence of bacterial colonies after treatment. DAPI staining decreased with 1% QAS (p 
    Matched MeSH terms: Bacterial Proteins/antagonists & inhibitors; Aminoacyltransferases/antagonists & inhibitors
  17. A review of the effects of ticagrelor on adenosine concentration and its clinical significance
    Akkaif MA, Ng ML, Sk Abdul Kader MA, Daud NAA, Sha'aban A, Ibrahim B
    Pharmacol Rep, 2021 Dec;73(6):1551-1564.
    PMID: 34283374 DOI: 10.1007/s43440-021-00309-0
    BACKGROUND: Ticagrelor is an oral antiplatelet drug that can reversibly bind to the platelet P2Y12 receptor. Ticagrelor is metabolized mainly by CYP3A4 and produces a rapid blood concentration-dependent platelet inhibitory effect. Unlike other P2Y12 receptor antagonists, many clinical features of ticagrelor are not related to P2Y12 receptor antagonism.

    PURPOSE: This review aims to gather existing literature on the clinical effects of ticagrelor after inhibiting adenosine uptake.

    METHODOLOGY: The current study reviewed literature related to the effects of ticagrelor on adenosine metabolism. The review also examined the drug's biological effects and clinical characteristics to see how it could be used in a clinical setting.

    RESULTS: Many studies have shown that ticagrelor can inhibit equilibrative nucleoside transporter 1 (ENT1). This inhibition leads to intracellular adenosine uptake, increased adenosine half-life and plasma concentration levels and an enhanced adenosine-mediated biological effect.

    CONCLUSIONS: Based on the studies reviewed, it was found that ticagrelor essentially inhibits adenosine absorption of adenosine into cells through ENT1, which increases the concentration in the blood and subsequently increases the protection of the heart muscle by adenosine. It also prevents platelet aggregation, and extends the biological effects of coronary arteries. Moreover, it leads to a lower mortality rate in acute coronary syndrome (ACS) patients.

    Matched MeSH terms: Equilibrative Nucleoside Transporter 1/antagonists & inhibitors
  18. A review on epidermal growth factor receptor's role in breast and non-small cell lung cancer
    Subramaniyan V, Fuloria S, Gupta G, Kumar DH, Sekar M, Sathasivam KV, et al.
    Chem Biol Interact, 2022 Jan 05;351:109735.
    PMID: 34742684 DOI: 10.1016/j.cbi.2021.109735
    Epithelial growth factor receptor (EGFR) is a cell surface transmembrane receptor that mediates the tyrosine signaling pathway to carry the extracellular messages inside the cell and thereby alter the function of nucleus. This leads to the generation of various protein products to up or downregulate the cellular function. It is encoded by cell erythroblastosis virus oncogene B1, so called C-erb B1/ERBB2/HER-2 gene that acts as a proto-oncogene. It belongs to the HER-2 receptor-family in breast cancer and responds best with anti-Herceptin therapy (anti-tyrosine kinase monoclonal antibody). HER-2 positive breast cancer patient exhibits worse prognosis without Herceptin therapy. Similar incidence and prognosis are reported in other epithelial neoplasms like EGFR + lung non-small cell carcinoma and glioblastoma (grade IV brain glial tumor). Present study highlights the role and connectivity of EGF with various cancers via signaling pathways, cell surface receptors mechanism, macromolecules, mitochondrial genes and neoplasm. Present study describes the EGFR associated gene expression profiling (in breast cancer and NSCLC), relation between mitrochondrial genes and carcinoma, and several in vitro and in vivo models to screen the synergistic effect of various combination treatments. According to this study, although clinical studies including targeted treatments, immunotherapies, radiotherapy, TKi-EGFR combined targeted therapy have been carried out to investigate the synergism of combination therapy; however still there is a gap to apply the scenarios of experimental and clinical studies for further developments. This review will give an idea about the transition from experimental to most advanced clinical studies with different combination drug strategies to treat cancer.
    Matched MeSH terms: ErbB Receptors/antagonists & inhibitors
  19. Fulltext A ruthenium polypyridyl intercalator stalls DNA replication forks, radiosensitizes human cancer cells and is enhanced by Chk1 inhibition
    Gill MR, Harun SN, Halder S, Boghozian RA, Ramadan K, Ahmad H, et al.
    Sci Rep, 2016 08 25;6:31973.
    PMID: 27558808 DOI: 10.1038/srep31973
    Ruthenium(II) polypyridyl complexes can intercalate DNA with high affinity and prevent cell proliferation; however, the direct impact of ruthenium-based intercalation on cellular DNA replication remains unknown. Here we show the multi-intercalator [Ru(dppz)2(PIP)](2+) (dppz = dipyridophenazine, PIP = 2-(phenyl)imidazo[4,5-f][1,10]phenanthroline) immediately stalls replication fork progression in HeLa human cervical cancer cells. In response to this replication blockade, the DNA damage response (DDR) cell signalling network is activated, with checkpoint kinase 1 (Chk1) activation indicating prolonged replication-associated DNA damage, and cell proliferation is inhibited by G1-S cell-cycle arrest. Co-incubation with a Chk1 inhibitor achieves synergistic apoptosis in cancer cells, with a significant increase in phospho(Ser139) histone H2AX (γ-H2AX) levels and foci indicating increased conversion of stalled replication forks to double-strand breaks (DSBs). Normal human epithelial cells remain unaffected by this concurrent treatment. Furthermore, pre-treatment of HeLa cells with [Ru(dppz)2(PIP)](2+) before external beam ionising radiation results in a supra-additive decrease in cell survival accompanied by increased γ-H2AX expression, indicating the compound functions as a radiosensitizer. Together, these results indicate ruthenium-based intercalation can block replication fork progression and demonstrate how these DNA-binding agents may be combined with DDR inhibitors or ionising radiation to achieve more efficient cancer cell killing.
    Matched MeSH terms: Checkpoint Kinase 1/antagonists & inhibitors
  20. Fulltext A secondary mode of action of polymyxins against Gram-negative bacteria involves the inhibition of NADH-quinone oxidoreductase activity
    Deris ZZ, Akter J, Sivanesan S, Roberts KD, Thompson PE, Nation RL, et al.
    J Antibiot (Tokyo), 2014 Feb;67(2):147-51.
    PMID: 24169795 DOI: 10.1038/ja.2013.111
    Polymyxin B and colistin were examined for their ability to inhibit the type II NADH-quinone oxidoreductases (NDH-2) of three species of Gram-negative bacteria. Polymyxin B and colistin inhibited the NDH-2 activity in preparations from all of the isolates in a concentration-dependent manner. The mechanism of NDH-2 inhibition by polymyxin B was investigated in detail with Escherichia coli inner membrane preparations and conformed to a mixed inhibition model with respect to ubiquinone-1 and a non-competitive inhibition model with respect to NADH. These suggest that the inhibition of vital respiratory enzymes in the bacterial inner membrane represents one of the secondary modes of action for polymyxins.
    Matched MeSH terms: NAD/antagonists & inhibitors; Quinone Reductases/antagonists & inhibitors*; Ubiquinone/antagonists & inhibitors
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