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1.
Phytother Res ; 35(12): 6963-6973, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34697842

ABSTRACT

Symptoms and complications associated with severe SARS-CoV-2 infection such as acute respiratory distress syndrome (ARDS) and organ damage have been linked to SARS-CoV-2 spike protein S1-induced increased production of pro-inflammatory cytokines by immune cells. In this study, the effects of an extract of Garcinia kola seeds and garcinoic acid were investigated in SARS-CoV-2 spike protein S1-stimulated human PBMCs. Results of ELISA experiments revealed that Garcinia kola extract (6.25, 12.5, and 25 µg/ml) and garcinoic acid (1.25, 2.5, and 5 µM) significantly reduced SARS-CoV-2 spike protein S1-induced secretion of TNFα, IL-6, IL-1ß, and IL-8 in PBMCs. In-cell western assays showed that pre-treatment with Garcinia kola extract and garcinoic acid reduced expressions of both phospho-p65 and phospho-IκBα proteins, as well as NF-κB DNA binding capacity and NF-κB-driven luciferase expression following stimulation of PBMCs with spike protein S1. Furthermore, pre-treatment of PBMCs with Garcinia kola extract prior to stimulation with SARS-CoV-2 spike protein S1 resulted in reduced damage to adjacent A549 lung epithelial cells. These results suggest that the seed of Garcinia kola and garcinoic acid are natural products which may possess pharmacological/therapeutic benefits in reducing cytokine storm in severe SARS-CoV-2 and other coronavirus infections.


Subject(s)
Benzopyrans/pharmacology , Garcinia kola , Leukocytes, Mononuclear/virology , NF-kappa B , SARS-CoV-2/drug effects , Spike Glycoprotein, Coronavirus/immunology , COVID-19 , Cells, Cultured , Garcinia kola/chemistry , Humans , Inflammation/drug therapy
2.
Preprint in English | bioRxiv | ID: ppbiorxiv-444690

ABSTRACT

Symptoms and complications associated with severe SARS-CoV-2 infection such as acute respiratory distress syndrome (ARDS) and organ damage have been linked to SARS-CoV-2 spike glycoprotein S1-induced increased production of pro-inflammatory cytokines by immune cells. In this study, the effects of an extract of Garcinia kola seeds and garcinoic acid were investigated in SARS-CoV-2 spike glycoprotein S1-stimulated human PBMCs. Results of ELISA experiments revealed that Garcinia kola extract (6.25, 12.5 and 25 g/mL) and garcinoic acid (1.25, 2.5 and 5 M) significantly reduced SARS-CoV-2 spike glycoprotein S1-induced increased secretion of TNF, IL-6, IL-1{beta} and IL-8 in PBMCs. In-cell western assays showed that pre-treatment with Garcinia kola extract and garcinoic acid reduced elevated expressions of both phospho-p65 and phospho-{kappa}B proteins, as well as NF-{kappa}B DNA binding capacity and NF-{kappa}B-driven luciferase expression following stimulation of PBMCs with spike glycoprotein S1. Furthermore, pre-treatment of PBMCs with Garcinia kola extract prior to stimulation with SARS-CoV-2 spike glycoprotein S1 resulted in reduced damage to adjacent A549 lung epithelial cells. Gas Chromatography-Mass Spectrometry (GCMS) and HPLC-PDA confirmed the presence of garcinoic acid in the Garcinia kola extract used in this study. These results suggest that the seed of Garcinia kola and garcinoic acid are natural products which may possess pharmacological/therapeutic benefits in reducing cytokine storm during the late stage of severe SARS-CoV-2 and other coronavirus infections.

3.
J Pharm Pharmacol ; 73(1): 118-134, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33791805

ABSTRACT

OBJECTIVES: The effects of a root extract of Zanthoxylum zanthoxyloides on neuroinflammation in BV-2 microglia stimulated with LPS and hemozoin were investigated. METHODS: ELISA, enzyme immunoassay and Griess assay were used to evaluate levels of cytokines, PGE2 and NO in culture supernatants, respectively. Microglia-mediated neurotoxicity was evaluated using a BV-2 microglia-HT-22 neuron transwell co-culture. KEY FINDINGS: Treatment with Z. zanthoxyloides caused reduced elevated levels of TNFα, IL-6, IL-1ß, NO and PGE2, while increasing the levels of IL-10. In addition, there were reduced levels of iNOS and COX-2 proteins. This was accompanied by a prevention of microglia-mediated damage to HT-22 mouse hippocampal neurons. Z. zanthoxyloides reduced elevated levels of phospho-IκB and phospho-p65, while preventing degradation of IκB protein and DNA binding of p65. Further mechanistic studies revealed that Z. zanthoxyloides reduced the levels of pro-IL-1ß and IL-1ß in hemozoin-activated BV-2 microglia. This was accompanied by a reduction in caspase-1 activity and NLRP3 protein expression. Bioassay-guided fractionation resulted in the isolation of skimmianine as an anti-inflammatory compound in Z. zanthoxyloides. CONCLUSION: This is the first report showing the inhibition of neuroinflammation in LPS- and hemozoin-activated BV-2 microglia by the root extract of Z. zanthoxyloides by targeting the activation of both NF-κB and NLRP3 inflammasome.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Inflammation/metabolism , Microglia/drug effects , NF-kappa B/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Quinolines/pharmacology , Zanthoxylum/chemistry , Animals , Anti-Inflammatory Agents/isolation & purification , Anti-Inflammatory Agents/therapeutic use , Caspase 1/metabolism , Cell Line , Cyclooxygenase 2 Inhibitors/isolation & purification , Cyclooxygenase 2 Inhibitors/pharmacology , Cyclooxygenase 2 Inhibitors/therapeutic use , Cytokines/metabolism , Hemeproteins , Inflammasomes/metabolism , Inflammation/chemically induced , Inflammation/prevention & control , Interleukin-1beta/metabolism , Lipopolysaccharides , Mice , Microglia/metabolism , Microglia/pathology , Nitric Oxide Synthase Type II/metabolism , Phytotherapy , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Plant Roots , Quinolines/isolation & purification , Quinolines/therapeutic use , Tumor Necrosis Factor-alpha/metabolism
4.
J Ethnopharmacol ; 273: 113981, 2021 Jun 12.
Article in English | MEDLINE | ID: mdl-33647425

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Combretum species are used traditionally for the treatment of diarrhoea, hookworm, fever, inflammation, pain and infectious diseases. Infections are commonly caused by the intake of food contaminated with foodborne pathogens. These are a significant concern in the food industry owing to their ability to form biofilms and cause food spoilage, despite the availability of modern food preservation techniques. Combretum elaeagnoides Klotzsch (Combretaceae) is used in southern African traditional medicine against infections and diarrhoea. AIM OF THE STUDY: This study evaluated the antimicrobial ability of C. elaeagnoides leaf fractions and the isolated compound quercetin-3-O-rhamnoside against a panel of foodborne pathogens, and biofilms formed by them. The samples were also assessed for their antioxidant activity and cytotoxicity. MATERIALS AND METHODS: Fractions prepared from the methanol extract of the leaves, and a bioactive compound (quercetin-3-O-rhamnoside) isolated from the ethyl acetate fraction were investigated for activity against nine reference and clinical strains of foodborne pathogens. The microdilution method was used to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of the fractions and compound. The inhibition of biofilm formation and the crystal violet staining assays were used to determine the antibiofilm efficacy. The DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay and the 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) electron reduction assay were used to determine the antioxidant potential of the fractions and compound. The cytotoxicity was assessed using the 3-(4, 5-dimethylthiazolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay against Vero African monkey kidney cells. RESULTS: The fractions were active against all tested organisms, with MIC values ranging from 0.03 to 1.25 mg/mL. The best MBC was 0.63 mg/mL. All the fractions and the purified compound inhibited biofilm formation of Staphylococcus aureus and Salmonella Typhimurium, with percentage inhibition values greater than 50% at 1 mg/mL. The compound had very promising antibiofilm activity against Escherichia coli 1 (ATCC 25922) with percentage inhibition of >150%. The compound and fractions had good radical scavenging potential against the DPPH and ABTS radicals. Quercetin-3-O-rhamnoside and the fractions were relatively non-cytotoxic. CONCLUSION: The ability of the fractions and compound to reduce and inhibit biofilm biomass and their promising antioxidant potential provide motivation to further investigate the use of plants to protect food products from contamination, as well as to treat infections characterized by bacterial biofilms.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Combretum/chemistry , Food Microbiology , Plant Extracts/pharmacology , Plant Leaves/chemistry , Anti-Bacterial Agents/chemistry , Plant Extracts/chemistry
5.
Med J Malaysia ; 75(6): 685-690, 2020 11.
Article in English | MEDLINE | ID: mdl-33219178

ABSTRACT

OBJECTIVES: To design and develop a simple vision test algorithm for mobile application and perform a pilot study to determine its validity and reliability as a tool for vision test in the community. METHODS: A simple visual acuity test algorithm in the form of a single letter E display was designed as the optotype for development of a mobile application. The standardised optotype is presented at random to test visual acuity for corresponding level of 3/60, 6/60, 6/18, and 6/12. The final result is auto-generated based on the classification of the WHO for visual impairment and blindness. The Snellen chart was used as the gold standard to determine its validity while five different users were involved to determine its inter-rater reliability. A pilot study was performed between April till November 2019, in the Universiti Sultan Zainal Abidin Medical Centre (UMC) at Kuala Nerus and Mooris Optometrist Centre at Marang, Terengganu. A total of 279 participants aged four years old and above were involved in this study. RESULTS: The highest sensitivity was found at the vision level cut-off point of 6/12 with the percentage of 92.7% and 86.8% for the right and left eye, respectively. The specificity was more than 89% for all vision levels in both eyes. The Krippendorff's alpha value for the inter-rater reliability was 0.87 and 0.83. CONCLUSION: The relatively high level of validity and reliability obtained indicate the feasibility of using the designed optotype to develop a valid and reliable mobile app for vision test. The app can be used to screen vision by nonmedical persons, at anytime and anywhere to help improve public awareness and capability to correctly determine their visual status.


Subject(s)
Mobile Applications , Vision Screening , Algorithms , Child, Preschool , Humans , Pilot Projects , Reproducibility of Results
6.
Phytother Res ; 32(10): 1957-1966, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29786910

ABSTRACT

Agathisflavone is a bioactive compound in Anacardium occidentale. In this study, we investigated inhibition neuroinflammation in BV2 microglia by agathisflavone. Neuroprotective activity of the compound was investigated in differentiated SH-SY5Y cells. Experiments in lipopolysaccharide (LPS)-activated BV2 microglia showed that pretreatment with agathisflavone (5-20 µM) produced significant reduction in the release of tumour necrosis factor-α, interleukin-6, interleukin-1ß, NO, and PGE2 from the cells. Immunoblotting experiments also revealed that agathisflavone reduced levels of iNOS and COX-2 protein. Further studies revealed that agathisflavone reduced neuroinflammation by targeting critical steps in NF-κB signalling in BV2 microglia. Treatment of SH-SY5Y cells with conditioned medium from LPS-activated BV2 microglia produced a significant reduction in neuronal viability. However, conditioned medium from BV2 cells that were stimulated with LPS in the presence of agathisflavone did not induce neurotoxicity. Agathisflavone also produced neuroprotection in APPSwe plasmid-transfected SH-SY5Y neurons. The compound further attenuated LPS-induced and APPSwe plasmid-induced reduction in SIRT1 in BV2 microglia and SH-SY5Y, respectively. In the presence of EX527, agathisflavone lost its anti-inflammatory and neuroprotective activities. Our results suggest that agathisflavone inhibits neuroinflammation in BV2 microglia by targeting NF-κB signalling pathway. The compound also reduces neurotoxicity through mechanisms that are possibly linked to SIRT1 in the microglia and neurons.


Subject(s)
Anacardium/chemistry , Anti-Inflammatory Agents/pharmacology , Biflavonoids/pharmacology , Inflammation/metabolism , Microglia/drug effects , Animals , Cell Line, Tumor , Cyclooxygenase 2/metabolism , Dinoprostone/metabolism , Humans , Inflammation/drug therapy , Interleukin-1beta/metabolism , Interleukin-6/metabolism , Lipopolysaccharides/pharmacology , Mice , Microglia/metabolism , NF-kappa B/metabolism , Nitric Oxide/metabolism , Signal Transduction/drug effects , Sirtuin 1/metabolism , Tumor Necrosis Factor-alpha/metabolism
7.
Molecules ; 18(10): 12633-44, 2013 Oct 11.
Article in English | MEDLINE | ID: mdl-24126380

ABSTRACT

Croton species are used in folk medicine in the management of infections, inflammation and oxidative stress-related diseases. In order to isolate, characterize and evaluate the bioactive constituents of Croton menyharthii Pax leaf extracts, repeated column fractionation of the ethyl acetate fraction from a 20% aqueous methanol crude extract afforded three flavonols identified by NMR (1D and 2D) spectroscopic methods as myricetrin-3-O-rhamnoside (myricetrin, 1), quercetin-3-O-rhamnoside (2) and quercetin (3) along with an indole alkaloid, (E)-N-(4-hydroxycinnamoyl)-5-hydroxytryptamine, [trans-N-(p-coumaroyl) serotonin, 4]. All the compounds are reported from the leaf extract of this plant for the first time. The crude extracts, four solvent fractions (hexane, DCM, ethyl acetate and butanol) and isolated compounds obtained from the leaves were evaluated for their inhibitory effects on selected bacteria, a fungus (Candida albicans), cyclooxygenase (COX-2), α-glucosidase and acetylcholinesterase (AChE). Amongst the compounds, quercetin (3) was the most active against Bacillus subtilis and Candida albicans while myricetrin-3-O-rhamnoside (1) and trans-N-(p-coumaroyl) serotonin (4) were the most active compounds against Escherichia coli, Klebsiella pneumonia and Staphylococcus aureus. The inhibitory activity of myricetrin-3-O-rhamnoside (1) against COX-2 was insignificant while that of the other three compounds 2-4 was low. The AChE inhibitory activity of the alkaloid, trans-N-(p-coumaroyl) serotonin was high, with a percentage inhibitory activity of 72.6% and an IC50 value of 15.0 µg/mL. The rest of the compounds only had moderate activity. Croton menyharthii leaf extracts and isolated compounds inhibit α-glucosidase at very low IC50 values compared to the synthetic drug acarbose. Structure activity relationship of the isolated flavonols 1-3 is briefly outlined. Compounds 1-4 and the leaf extracts exhibited a broad spectrum of activities. This validates the ethnomedicinal use of the plant in folk medicine.


Subject(s)
Alkaloids/pharmacology , Anti-Bacterial Agents/pharmacology , Antifungal Agents/pharmacology , Croton/chemistry , Flavonols/pharmacology , Indoles/pharmacology , Plant Leaves/chemistry , Acetylcholinesterase/chemistry , Alkaloids/chemistry , Alkaloids/isolation & purification , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Antifungal Agents/chemistry , Antifungal Agents/isolation & purification , Bacillus subtilis/drug effects , Candida albicans/drug effects , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/isolation & purification , Cholinesterase Inhibitors/pharmacology , Cyclooxygenase 2/chemistry , Cyclooxygenase 2 Inhibitors/chemistry , Cyclooxygenase 2 Inhibitors/isolation & purification , Cyclooxygenase 2 Inhibitors/pharmacology , Electrophorus , Escherichia coli/drug effects , Fish Proteins/chemistry , Flavonols/chemistry , Flavonols/isolation & purification , Humans , Indoles/chemistry , Indoles/isolation & purification , Inhibitory Concentration 50 , Microbial Sensitivity Tests , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Staphylococcus aureus/drug effects
8.
J Ethnopharmacol ; 150(2): 609-13, 2013 Nov 25.
Article in English | MEDLINE | ID: mdl-24060408

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Searsia chirindensis is used in South African traditional medicine for management of bacterial infections such as diarrhoea. Aim of the study was to examine the phytochemical composition from the leaves of Searsia chirindensis that is responsible for the ethnomedicinal use of this plant. MATERIALS AND METHODS: The crude extract (80% methanol) was extracted sequentially with dichloromethane (DCM), ethyl acetate (EtOAc) and n-butanol. The extracts and isolated compounds were tested for their antibacterial activity against Gram-negative (Campylobacter jejuni, Escherichia coli and Shigella flexneri) and Gram-positive (Staphylococcus aureus) bacterial strains using the microdilution method. Bioguided fractionation of EtOAc fraction afforded five phenolic compounds. Structural elucidation was carried out using NMR (1D and 2D) spectroscopic analyses. RESULTS: Of the three fractions obtained from the crude extract, EtOAc was the most active and its fractionation afforded methyl gallate (1), and four flavonol glycosides: myricetin-3-O-arabinopyranoside (2), myricetrin-3-O-rhamnoside (3), kaempferol-3-O-rhamnoside (4) and quercetin-3-O-arabinofuranoside (5). These compounds are reported from Searsia chirindensis for the first time. All the compounds showed good antibacterial activity against all bacterial strains tested. Their minimum inhibitory concentrations ranged from 30 to 250 µg/mL. CONCLUSIONS: Antibacterial activity demonstrated by the extracts and isolated compounds provides credence to the ethnomedicinal use of Searsia chirindensis against diarrhoea.


Subject(s)
Anacardiaceae , Anti-Bacterial Agents/pharmacology , Gram-Negative Bacteria/drug effects , Plant Extracts/pharmacology , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/isolation & purification , Gallic Acid/analogs & derivatives , Gallic Acid/isolation & purification , Gallic Acid/pharmacology , Glycosides/isolation & purification , Glycosides/pharmacology , Microbial Sensitivity Tests , Plant Extracts/chemistry , Plant Leaves
9.
Food Chem ; 141(2): 1412-5, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-23790932

ABSTRACT

Alpha-glucosidase inhibitors play a potential role in the treatment of type 2 diabetes by delaying glucose absorption in the small intestine. Ecklonia maxima, a brown alga which grows abundantly on the west coast of South Africa, is used to produce alginate, animal feed, nutritional supplements and fertilizer. The crude aqueous methanol extract, four solvent fractions and three phlorotannins: 1,3,5-trihydroxybenezene (phloroglucinol) (1), dibenzo [1,4] dioxine-2,4,7,9-tetraol (2) and hexahydroxyphenoxydibenzo [1,4] dioxine (eckol) (3) isolated from E. maxima were evaluated for antiradical and alpha-glucosidase inhibitory activities. All the phlorotannins tested had strong antioxidant activities on DPPH free radicals with EC50 values ranging from 0.008 to 0.128µM. Compounds 2 and 3 demonstrated stronger antioxidant activity and an alpha-glucosidase inhibitory property than positive controls. These results suggest that E. maxima could be a natural source of potent antioxidants and alpha-glucosidase inhibitors. This study could facilitate effective utilization of E. maxima as an oral antidiabetic drug or functional food ingredient with a promising role in the formulation of medicines and nutrition supplements.


Subject(s)
Antioxidants/analysis , Enzyme Inhibitors/analysis , Fungal Proteins/antagonists & inhibitors , Glycoside Hydrolase Inhibitors , Phaeophyceae/chemistry , Vegetables/chemistry , Antioxidants/isolation & purification , Enzyme Inhibitors/isolation & purification , Fungal Proteins/analysis , Yeasts/enzymology , alpha-Glucosidases/analysis
10.
Molecules ; 18(2): 1916-32, 2013 Feb 01.
Article in English | MEDLINE | ID: mdl-23377133

ABSTRACT

A comparative evaluation of the antioxidant and acetylcholinesterase inhibitory activity of the leaf extracts of Croton gratissimus and Croton zambesicus (subgratissimus) and compounds isolated from the extracts was carried out to determine their potential and suitability or otherwise as a substitute for each other in the management of oxidative and neurodegenerative conditions. Different antioxidant assays (DPPH, FRAP, ß-carotene-linoleic and the lipid peroxidation models) and the microplate assay for acetylcholinesterase (AChE) inhibition were carried out separately to study the activities of the crude leaf extracts and four solvent fractions from each of the two Croton species. Bioassay guided fractionation was used to target antioxidant constituents of the crude extracts and ethyl acetate fractions of 20% aqueous methanol extract of C. gratissimus on silica gel and Sephadex LH-20 columns resulted in the isolation of kaempferol-3-O-ß-6''(p-coumaroyl) glucopyranoside (tiliroside, 2), apigenin-6-C-glucoside (isovitexin, 3) and kampferol (4). The extract of C. zambesicus yielded quercetin-3-O-ß-6''(p-coumaroyl) glucopyranoside-3'-methyl ether (helichrysoside- 3'-methyl ether, 1), kaempferol-3-O-ß-6''(p-coumaroyl) glucopyranoside (tiliroside, 2) and apigenin-6-C-glucoside (isovitexin, 3). Three of the isolated compounds and their different combinations were also included in the bioassays. In all the assays performed, the antioxidant capacity and AChE inhibitory effects of C. zambesicus extracts were weaker than those of C. gratissimus. This suggests that C. gratissimus may not be substituted by C. zambesicus, despite the similarity in some of their constituents. Generally, the combinations made from the isolated compounds showed better activities in most of the assays compared to the individual isolated compounds. This suggests mechanisms such as synergism and/or additive effects to be taking place. This study established low, moderate and high antioxidant activities as well as AChE inhibitory effects by the crude extracts, fractions, compounds and compound combinations. This means some of the extracts, isolated compounds and compound combinations could be useful in the management of neurodegenerative conditions and serve as sources of natural neurodegenerative agents.


Subject(s)
Antioxidants/pharmacology , Biological Products/isolation & purification , Biological Products/pharmacology , Cholinesterase Inhibitors/pharmacology , Croton/chemistry , Plant Extracts/pharmacology , Plant Leaves/chemistry , Antioxidants/chemistry , Biological Assay , Biological Products/chemistry , Biphenyl Compounds/metabolism , Cholinesterase Inhibitors/chemistry , Free Radical Scavengers/pharmacology , Iron/metabolism , Linoleic Acid/metabolism , Lipid Peroxidation/drug effects , Malondialdehyde/metabolism , Models, Biological , Oxidation-Reduction/drug effects , Phospholipids/metabolism , Picrates/metabolism , Thiobarbituric Acid Reactive Substances/metabolism , beta Carotene/metabolism
11.
Epidemiol Infect ; 141(7): 1481-7, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23414617

ABSTRACT

A cross-sectional study was conducted from 10 January to 9 April 2012, to determine the seroprevalence of tuberculosis (TB) of all captive Asian elephants and their handlers in six locations in Peninsular Malaysia. In addition, trunk-wash samples were examined for tubercle bacillus by culture and polymerase chain reaction (PCR). For 63 elephants and 149 elephant handlers, TB seroprevalence was estimated at 20.4% and 24.8%, respectively. From 151 trunkwash samples, 24 acid-fast isolates were obtained, 23 of which were identified by hsp65-based sequencing as non-tuberculous mycobacteria. The Mycobacterium tuberculosis-specific PCR was positive in the trunk-wash samples from three elephants which were also seropositive. Conversely, the trunk wash from seven seropositive elephants were PCR negative. Hence, there was evidence of active and latent TB in the elephants and the high seroprevalence in the elephants and their handlers suggests frequent, close contact, two-way transmission between animals and humans within confined workplaces.


Subject(s)
Animals, Zoo , Elephants , Tuberculosis/veterinary , Zoonoses/epidemiology , Animals , Antigens, Bacterial/blood , Biomarkers/blood , Cross-Sectional Studies , DNA, Bacterial/analysis , Humans , Interferon-gamma Release Tests , Malaysia/epidemiology , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/immunology , Mycobacterium tuberculosis/isolation & purification , Polymerase Chain Reaction , Prevalence , Risk , Seroepidemiologic Studies , Tuberculosis/diagnosis , Tuberculosis/epidemiology , Tuberculosis/transmission , Zoonoses/transmission
12.
J Ethnopharmacol ; 145(1): 42-9, 2013 Jan 09.
Article in English | MEDLINE | ID: mdl-23142196

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Anacardium occidentale is used in traditional African medicine for the treatment of arthritis, fever, aches, pains, and inflammation of the extremities. AIM OF THE STUDY: In this study, we investigated the molecular mechanisms responsible for anti-inflammatory effects of a stem bark extract of A. occidentale (ANE) in LPS-stimulated microglia. MATERIALS AND METHODS: Nitric oxide (NO), prostaglandin E(2) and cytokine (TNFα and IL-6) production were evaluated in supernatants from LPS-stimulated BV-2 cells. Cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS) and microsomal prostaglandin E2 synthase (mPGES-1) protein expressions in rat primary microglia were measured using western blot. The effects of ANE on NF-κB activation and nuclear translocation were evaluated in the luciferase reporter gene assay and ELISA, while ability of ANE to influence IκB phosphorylation was determined using ELISA specific for phospho-IκB. The involvement of MAPK phosphorylation in the anti-inflammatory actions of ANE was evaluated using specific ELISA for phospho-p38, phospho-p42/44 and phospho-JNK. The MTT assay was used to determine the effect of ANE on BV-2 microglia viability. RESULTS: ANE (25-100 µg/ml) produced significant (p<0.05) reduction in the production of NO, PGE(2), TNFα and IL-6 in BV-2 microglia stimulated with LPS for 24h. Pre-treatment with ANE caused a significant (p<0.05) inhibition of COX-2, iNOS and mPGES-1 protein expressions in the rat primary microglia. Further experiments showed that ANE inhibited COX-2 and iNOS protein expression via IκB-mediated nuclear translocation and transactivation of NF-κB. Our studies also revealed that ANE produced significant (p<0.05) and dose-dependent inhibition of p38, p42/44 and JNK MAPK phosphorylation in LPS-activated BV-2 microglia. CONCLUSIONS: We conclude that ANE has an anti-inflammatory property related to inhibition of inflammation-associated cytokine production as well as iNOS and COX-2 gene expression by blocking NF-κB and MAPK pathways in the microglia. It is also suggested that mPGES-1 inhibition contributes to the effect of ANE on PGE(2) production in the microglia.


Subject(s)
Anti-Inflammatory Agents/pharmacology , MAP Kinase Signaling System/drug effects , Microglia/drug effects , NF-kappa B/metabolism , Anacardium/chemistry , Animals , Cell Survival/drug effects , Cells, Cultured , Cyclooxygenase 2/metabolism , Cytokines/metabolism , Dinoprostone/metabolism , Humans , Mice , Microglia/metabolism , Mitogen-Activated Protein Kinases/metabolism , Nitric Oxide/metabolism , Plant Bark/chemistry , Plant Extracts/pharmacology , Signal Transduction/drug effects
13.
Article in English | MEDLINE | ID: mdl-23320030

ABSTRACT

Bridelia ferruginea is commonly used in traditional African medicine (TAM) for treating various inflammatory conditions. Extracts from the plant have been shown to exhibit anti-inflammatory property in a number of in vivo models. In this study the influence of B. ferruginea (BFE) on the production of PGE(2), nitrite, and proinflammatory cytokines from LPS-stimulated BV-2 microglia was investigated. The effects of BFE on cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) protein expressions were evaluated in LPS-activated rat primary microglia. The roles of NF-κB and MAPK signalling in the actions of BFE were also investigated. BFE (25-200 µg) inhibited the production of PGE(2), nitrite, tumour necrosis factor-α (TNFα), and interleukin-6 (IL-6) as well as COX-2 and iNOS protein expressions in LPS-activated microglial cells. Further studies to elucidate the mechanism of anti-inflammatory action of BFE revealed interference with nuclear translocation of NF-κBp65 through mechanisms involving inhibition of IκB degradation. BFE prevented phosphorylation of p38, but not p42/44 or JNK MAPK. It is suggested that Bridelia ferruginea produces anti-inflammatory action through mechanisms involving p38 MAPK and NF-κB signalling.

14.
Trop Biomed ; 28(3): 497-505, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22433877

ABSTRACT

A simple and reliable tool for the early diagnosis of leptospirosis is urgently needed. We report the development of a lyophilized reagent-based polymerase chain reaction (PCR) assay targeting lipL32 gene, which is present only in pathogenic leptospires. To determine the effectiveness of the newly developed assay in the early diagnosis of leptospirosis, the sensitivity and specificity was evaluated. In simulated clinical samples, the assay was able to detect 10² and 10³ leptospires/ml in spiked urine and blood samples, respectively. In experimentally infected animals, leptospiral DNA could be detected in blood and lung samples as early as Day 1 post infection. This assay was also shown to be stable and remained sensitive for up to five months at ambient temperature. Hence, this lyophilized reagent-based PCR assay with high specificity, sensitivity and stability would provide a simple, rapid and reliable method in diagnosing acute leptospirosis, especially in the field of veterinary medicine.


Subject(s)
Bacteriological Techniques/methods , Freeze Drying , Leptospira/genetics , Leptospira/isolation & purification , Leptospirosis/diagnosis , Molecular Diagnostic Techniques/methods , Polymerase Chain Reaction/methods , Animals , Blood/microbiology , Cricetinae , Disease Models, Animal , Humans , Lung/microbiology , Mesocricetus , Reagent Kits, Diagnostic , Sensitivity and Specificity , Urine/microbiology
15.
Tropical Biomedicine ; : 497-505, 2011.
Article in English | WPRIM (Western Pacific) | ID: wpr-630078

ABSTRACT

A simple and reliable tool for the early diagnosis of leptospirosis is urgently needed. We report the development of a lyophilized reagent-based polymerase chain reaction (PCR) assay targeting lipL32 gene, which is present only in pathogenic leptospires. To determine the effectiveness of the newly developed assay in the early diagnosis of leptospirosis, the sensitivity and specificity was evaluated. In simulated clinical samples, the assay was able to detect 102 and 103 leptospires/ml in spiked urine and blood samples, respectively. In experimentally infected animals, leptospiral DNA could be detected in blood and lung samples as early as Day 1 post infection. This assay was also shown to be stable and remained sensitive for up to five months at ambient temperature. Hence, this lyophilized reagent-based PCR assay with high specificity, sensitivity and stability would provide a simple, rapid and reliable method in diagnosing acute leptospirosis, especially in the field of veterinary medicine

16.
Trop Biomed ; 27(1): 30-2, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20562810

ABSTRACT

One hundred and sixty eight rats were trapped from the National Service Training Centres (NSTC) in Kelantan and Terengganu from October 2008 to May 2009. Microscopic agglutination test (MAT) was performed to detect the presence of agglutinating antibodies to Leptospira among the rats caught. All the MAT positive rats were identified as Rattus tiomanicus. In Kelantan, 17.3 % (14/81) of the rats had leptospiral antibodies to serovars Icterohaemorrhagiae (12.3%), Canicola (2.5%), Ballum (1.2%), and Pyrogenes (1.2%). In Terengganu, 18.4% (16/87) of the rats had antibodies to serovars Icterohaemorrhagiae (15%), Canicola (1.1%), Pyrogenes (1.1%) and Hebdomadis (1.1%). This study indicated that Leptospira serovars were prevalent in the rat population in the study areas and could be a source of infection to humans. Therefore, control of the rat population in all NSTC is critical to prevent outbreaks of leptospirosis amongst the NSTC trainees.


Subject(s)
Leptospirosis/veterinary , Animals , Animals, Wild , Leptospira/classification , Leptospira/isolation & purification , Leptospirosis/blood , Leptospirosis/epidemiology , Malaysia/epidemiology , Rats , Seroepidemiologic Studies
17.
Trop Biomed ; 27(3): 632-8, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21399605

ABSTRACT

Leptospirosis is recognized as one of the important zoonotic diseases in the world including Malaysia. A total of 145 soil and water samples were collected from selected National Service Training Centres (NSTC) in Kelantan and Terengganu. The samples were inoculated into modified semisolid Ellinghausen McCullough Johnson Harris (EMJH) medium, incubated at room temperature for 1 month and examined under the dark-field microscope. Positive growth of the leptospiral isolates were then confirmed with 8-Azaguanine Test, Polymerase Chain Reaction (PCR) assay and Microscopic Agglutination Test (MAT). Fifteen cultures (10.34%) exhibited positive growths which were seen under dark field microscope whilst only 20% (3/15) were confirmed as pathogenic species. based on 8-Azaguanine Test and PCR. Serological identification of the isolates with MAT showed that hebdomadis was the dominant serovar in Terengganu. Pathogenic leptospires can be detected in Malaysian environment and this has the potential to cause an outbreak. Therefore, precautionary steps against leptospirosis should be taken by camp authorities to ensure the safety of trainees.


Subject(s)
Leptospira/isolation & purification , Soil Microbiology , Water Microbiology , Agglutination Tests , Animals , Antimetabolites/metabolism , Azaguanine/metabolism , Bacteriological Techniques , Culture Media/chemistry , Humans , Malaysia , Microscopy , Polymerase Chain Reaction , Serotyping
18.
Tropical Biomedicine ; : 30-2, 2010.
Article in English | WPRIM (Western Pacific) | ID: wpr-630016

ABSTRACT

One hundred and sixty eight rats were trapped from the National Service Training Centres (NSTC) in Kelantan and Terengganu from October 2008 to May 2009. Microscopic agglutination test (MAT) was performed to detect the presence of agglutinating antibodies to Leptospira among the rats caught. All the MAT positive rats were identified as Rattus tiomanicus. In Kelantan, 17.3 % (14/81) of the rats had leptospiral antibodies to serovars Icterohaemorrhagiae (12.3%), Canicola (2.5%), Ballum (1.2%), and Pyrogenes (1.2%). In Terengganu, 18.4% (16/87) of the rats had antibodies to serovars Icterohaemorrhagiae (15%), Canicola (1.1%), Pyrogenes (1.1%) and Hebdomadis (1.1%). This study indicated that Leptospira serovars were prevalent in the rat population in the study areas and could be a source of infection to humans. Therefore, control of the rat population in all NSTC is critical to prevent outbreaks of leptospirosis amongst the NSTC trainees.

19.
Med J Malaysia ; 59(2): 153-9, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15559163

ABSTRACT

A total of 157 stool samples were examined for Group A rotaviruses in diarrheic children admitted to 8 different major hospitals in Malaysia. The overall incidence rate in this study was 19.7% (31 of 157) with a variation of 9.5% to 39.1% in different locations. Majority of the infections detected were in those under 2 years of age and there were fewer admissions in the older age group. The stool samples were initially screened for rotavirus Group A by latex agglutination method and followed by RNA electrophoresis. The size and the characteristics wheel-shaped morphology of the viral preparations when examined by electron-microscopy further confirmed the presence of rotaviruses in the positive stool samples. Analysis of the RNA pattern showed that majority of the isolates, 51.6% (16 of 31) were Type IIC ('long' with comigration of RNA segments 7 and 8), 35.5% (11 of 31) with Type IIG ('long' with comigration of segments 7, 8, 9), 9.7% (3 of 31) with Type IG ('short' with comigration of RNA segments 7, 8, 9) and 3.2% (1 of 31) of mixed or atypical pattern. It appeared that over a 12 year interval, only one new or unusual rotavirus electropherotype was found. This is the first comprehensive report on the electropherotypes of rotaviruses covering eight different geographical locations in Malaysia and the data obtained is useful for understanding the geographic distribution and types of rotaviruses transmitting in Malaysia.


Subject(s)
Rotavirus Infections/epidemiology , Rotavirus/genetics , Age Factors , Child, Preschool , Electrophoresis, Polyacrylamide Gel , Feces/microbiology , Female , Humans , Incidence , Infant , Latex Fixation Tests , Malaysia/epidemiology , Male , Microscopy, Electron , RNA, Viral/genetics , Rotavirus Infections/virology
20.
J Ethnopharmacol ; 84(1): 1-4, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12499068

ABSTRACT

Crude ethanol and water extract of leaves and barks from Cassia alata were tested in vitro against fungi, (Aspergillus fumigatus and Microsporum canis), yeast (Candida albicans) and bacteria (Staphylococcus aereus and Escherichia coli). C. albicans showed concentration-dependent susceptibility towards both the ethanol and water extracts from the barks, but resistant towards the extracts of leaves. The degree of susceptibility varied, the water extract from barks showed bigger inhibition zone than the ethanol extracts (12-16 and 10-14 mm, diameter respectively). The growth of Aspergillus fumigatus and Microsporum canis were not affected by all types of the plant extracts. Results were comparable to standard antifungal drug Tioconazole (18 mm diameter) at equivalent concentration. The anti-bacterial activity of C. alata extracts on S. aureus was detected with only the leaves extracts using water and ethanol. The water extract exhibited higher antibacterial activity than the ethanol extract from leaves (inhibition zones of 11-14 and 9-11 mm, respectively). E. coli showed resistance to all types of extracts. Based on the current findings, it can be concluded that this plant has antimicrobial activity, which is as potent as standard antimicrobial drugs against certain microorganisms.


Subject(s)
Anti-Infective Agents/pharmacology , Cassia/chemistry , Plant Extracts/pharmacology , Anti-Bacterial Agents , Aspergillus fumigatus/drug effects , Escherichia coli/drug effects , Ethanol , Malaysia , Medicine, Traditional , Microsporum/drug effects , Plant Bark/chemistry , Plant Leaves/chemistry , Staphylococcus aureus/drug effects , Water
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