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  1. Fulltext Alkyl-Resorcinol Derivatives as Inhibitors of GDP-Mannose Pyrophosphorylase with Antileishmanial Activities
    Levaique H, Pamlard O, Apel C, Bignon J, Arriola M, Kuhner R, et al.
    Molecules, 2021 Mar 11;26(6).
    PMID: 33799883 DOI: 10.3390/molecules26061551
    Leishmaniasis is a vector-borne disease caused by the protozoan parasite Leishmania found in tropical and sub-tropical areas, affecting 12 million people around the world. Only few treatments are available against this disease and all of them present issues of toxicity and/or resistance. In this context, the development of new antileishmanial drugs specifically directed against a therapeutic target appears to be a promising strategy. The GDP-Mannose Pyrophosphorylase (GDP-MP) has been previously shown to be an attractive therapeutic target in Leishmania. In this study, a chemical library of 5000 compounds was screened on both L. infantum (LiGDP-MP) and human (hGDP-MP) GDP-MPs. From this screening, oncostemonol D was found to be active on both GDP-MPs at the micromolar level. Ten alkyl-resorcinol derivatives, of which oncostemonols E and J (2 and 3) were described for the first time from nature, were then evaluated on both enzymes as well as on L. infantum axenic and intramacrophage amastigotes. From this evaluation, compounds 1 and 3 inhibited both GDP-MPs at the micromolar level, and compound 9 displayed a three-times lower IC50 on LiGDP-MP, at 11 µM, than on hGDP-MP. As they displayed mild activities on the parasite, these compounds need to be further pharmacomodulated in order to improve their affinity and specificity to the target as well as their antileishmanial activity.
    Matched MeSH terms: RAW 264.7 Cells
  2. Fulltext Molecular phylogenetics of a recently isolated goat pox virus from Vietnam
    Pham TH, Rahaman NYA, Lila MAM, Lai HLT, Nguyen LT, Van Nguyen G, et al.
    BMC Vet Res, 2021 Mar 08;17(1):115.
    PMID: 33685458 DOI: 10.1186/s12917-021-02777-1
    BACKGROUND: After a decade of silence, an outbreak of the contagious and Asian endemic disease, goat pox re-emerged in North Vietnam affecting more than 1800 heads with a mortality rate of 6.5%. The inevitable impact of goat pox on hide quality, breeding, chevon and milk production has resulted in a significant economic losses to the developing goat industry of Vietnam. In the act of establishing an effective control of this devastating disease, tracing the source of re-emergence via a phylogenetic study was carried out to reveal their genetic relatedness. Either skin scab or papule from the six affected provinces were collected, cultured into Vero cells followed by restricted enzyme digestion of targeted P32 gene DNA encoding. The P32 gene was then cloned and transformed into E.coli competent cells for further sequencing.

    RESULTS: The isolated sequence is deposited into GenBank under Accession No. MN317561/VNUAGTP1. The phylogenetic tree revealed high similarity of nucleotide and amino acid sequences to references goat pox strains accounting for 99.6 and 99.3, respectively. The Vietnamese strain is clustered together with currently circulating goat pox virus in China, India and Pakistan which suggested the origin of South China.

    CONCLUSIONS: This Vietnam isolate is clustered together with other Asian goat pox strains indicating the dissemination of a common goat pox virus within this continent.

    Matched MeSH terms: Vero Cells
  3. The effect of TGF-beta1 and beta-estradiol on glycosaminoglycan and type II collagen distribution in articular chondrocyte cultures
    Ab-Rahim S, Selvaratnam L, Kamarul T
    Cell Biol Int, 2008 Jul;32(7):841-7.
    PMID: 18479947 DOI: 10.1016/j.cellbi.2008.03.016
    Articular cartilage extracellular matrix (ECM) plays a crucial role in regulating chondrocyte functions via cell-matrix interaction, cytoskeletal organization and integrin-mediated signaling. Factors such as interleukins, basic fibroblast growth factor (bFGF), bone morphogenic proteins (BMPs) and insulin-like growth factor (IGF) have been shown to modulate the synthesis of extracellular matrix in vitro. However, the effects of TGF-beta1 and beta-estradiol in ECM regulation require further investigation, although there have been suggestions that these factors do play a positive role. To establish the role of these factors on chondrocytes derived from articular joints, a study was conducted to investigate the effects of TGF-beta1 and beta-estradiol on glycosaminoglycan secretion and type II collagen distribution (two major component of cartilage ECM in vivo). Thus, chondrocyte cultures initiated from rabbit articular cartilage were treated with 10ng/ml of TGF-beta1, 10nM of beta-estradiol or with a combination of both factors. Sulphated glycosaminoglycan (GAG) and type II collagen levels were then measured in both these culture systems. The results revealed that the synthesis of GAG and type II collagen was shown to be enhanced in the TGF-beta1 treated cultures. This increase was also noted when TGF-beta1 and beta-estradiol were both used as culture supplements. However, beta-estradiol alone did not appear to affect GAG or type II collagen deposition. There was also no difference between the amount of collagen type II and GAG being expressed when chondrocyte cultures were treated with TGF-beta1 when compared with cultures treated with combined factors. From this, we conclude that although TGF-beta1 appears to stimulate chondrocyte ECM synthesis, beta-estradiol fails to produce similar effects. The findings of this study confirm that contrary to previous claims, beta-estradiol has little or no effect on chondrocyte ECM synthesis. Furthermore, the use of TGF-beta1 may be useful in future studies looking into biological mechanisms by which ECM synthesis in chondrocyte cultures can be augmented, particularly for clinical application.
    Matched MeSH terms: Cells, Cultured
  4. Synthetic Dihydropyridines as Novel Antiacanthamoebic Agents
    Anwar A, Siddiqui R, Hameed A, Shah MR, Khan NA
    Med Chem, 2020;16(7):841-847.
    PMID: 31544702 DOI: 10.2174/1573406415666190722113412
    BACKGROUND: Acanthamoeba is an opportunistic pathogen widely spread in the environment. Acanthamoeba causes excruciating keratitis which can lead to blindness. The lack of effective drugs and its ability to form highly resistant cyst are one of the foremost limitations against successful prognosis. Current treatment involves mixture of drugs at high doses but still recurrence of infection can occur due to ineffectiveness of drugs against the cyst form. Pyridine and its natural and synthetic derivatives are potential chemotherapeutic agents due to their diverse biological activities.

    OBJECTIVE: To study the antiamoebic effects of four novel synthetic dihydropyridine (DHP) compounds against Acanthamoeba castellanii belonging to the T4 genotype. Furthermore, to evaluate their activity against amoeba-mediated host cells cytopathogenicity as well as their cytotoxicity against human cells.

    METHODS: Dihydropyridines were synthesized by cyclic dimerization of alkylidene malononitrile derivatives. Four analogues of functionally diverse DHPs were tested against Acanthamoeba castellanii by using amoebicidal, encystation and excystation assays. Moreover, Lactate dehydrogenase assays were carried out to study cytopathogenicity and cytotoxicity against human cells.

    RESULTS: These compounds showed significant amoebicidal and cysticidal effects at 50 μM concentration, whereas, two of the DHP derivatives also significantly reduced Acanthamoebamediated host cell cytotoxicity. Moreover, these DHPs were found to have low cytotoxicity against human cells suggesting a good safety profile.

    CONCLUSION: The results suggest that DHPs have potential against Acanthamoeba especially against the more resistant cyst stage and can be assessed further for drug development.

    Matched MeSH terms: HeLa Cells
  5. Fulltext Production and purification of polymerization-competent HIV-1 capsid protein p24 (CA) in NiCo21(DE3) Escherichia coli
    Teow SY, Mualif SA, Omar TC, Wei CY, Yusoff NM, Ali SA
    BMC Biotechnol, 2013;13:107.
    PMID: 24304876 DOI: 10.1186/1472-6750-13-107
    HIV genome is packaged and organized in a conical capsid, which is made up of ~1,500 copies of the viral capsid protein p24 (CA). Being a primary structural component and due to its critical roles in both late and early stages of the HIV replication cycle, CA has attracted increased interest as a drug discovery target in recent years. Drug discovery studies require large amounts of highly pure and biologically active protein. It is therefore desirable to establish a simple and reproducible process for efficient production of HIV-1 CA.
    Matched MeSH terms: HEK293 Cells
  6. Extraction, anti-tyrosinase, and antioxidant activities of the collagen hydrolysate derived from Rhopilema hispidum
    Ab Aziz NA, Salim N, Zarei M, Saari N, Yusoff FM
    Prep Biochem Biotechnol, 2021;51(1):44-53.
    PMID: 32701046 DOI: 10.1080/10826068.2020.1789991
    The study was conducted to determine anti-tyrosinase and antioxidant activities of the extracted collagen hydrolysate (CH) derived from Malaysian jellyfish, Rhopilema hispidum. Collagen was extracted using 1:1 (w:v) 0.1 M NaOH solution at temperature 25 °C for 48 hr followed by treatment of 1:2 (w:v) distilled water for another 24 hr and freeze-dried. The extracted collagen was hydrolyzed using papain at optimum temperature, pH and enzyme/substrate ratio [E/S] of 60 °C, 7.0 and 1:50, respectively. CH was found to exhibit tyrosinase inhibitory activity, DPPH radical scavenging and metal ion-chelating assays up to 64, 28, and 83%, respectively, after 8 hr of hydrolysis process. The molecular weight of CH was found <10 kDa consisting of mainly Gly (19.219%), Glu (10.428%), and Arg (8.848%). The UV-visible spectrum analysis showed a major and minor peak at 218 and 276 nm, accordingly. The FTIR spectroscopy confirmed the amide groups in CH. The SEM images demonstrated spongy and porous structure of CH. In the cytotoxicity study, CH has no cytotoxicity against mouse embryonic 3T3 fibroblast cell line with IC50 value >500 µg/ml. Results revealed that the CH generated from this study has a potential to be developed as active ingredient in cosmeceutical application.
    Matched MeSH terms: 3T3 Cells
  7. Fulltext Molecular Action of Hydroxytyrosol in Attenuation of Intimal Hyperplasia: A Scoping Review
    Vijakumaran U, Yazid MD, Hj Idrus RB, Abdul Rahman MR, Sulaiman N
    Front Pharmacol, 2021;12:663266.
    PMID: 34093194 DOI: 10.3389/fphar.2021.663266
    Objective: Hydroxytyrosol (HT), a polyphenol of olive plant is well known for its antioxidant, anti-inflammatory and anti-atherogenic properties. The aim of this systematic search is to highlight the scientific evidence evaluating molecular efficiency of HT in halting the progression of intimal hyperplasia (IH), which is a clinical condition arises from endothelial inflammation. Methods: A systematic search was performed through PubMed, Web of Science and Scopus, based on pre-set keywords which are Hydroxytyrosol OR 3,4-dihydroxyphenylethanol, AND Intimal hyperplasia OR Neointimal hyperplasia OR Endothelial OR Smooth muscles. Eighteen in vitro and three in vitro and in vivo studies were selected based on a pre-set inclusion and exclusion criteria. Results: Based on evidence gathered, HT was found to upregulate PI3K/AKT/mTOR pathways and supresses inflammatory factors and mediators such as IL-1β, IL-6, E-selectin, P-selectin, VCAM-1, and ICAM-1 in endothelial vascularization and functioning. Two studies revealed HT disrupted vascular smooth muscle cells (SMC) cell cycle by dephosphorylating ERK1/2 and AKT pathways. Therefore, HT was proven to promote endothelization and inhibit vascular SMCs migration thus hampering IH development. However, none of these studies described the effect of HT collectively in both vascular endothelial cells (EC) and SMCs in IH ex vivo model. Conclusions: Evidence from this concise review provides an insight on HT regulation of molecular pathways in reendothelization and inhibition of VSMCs migration. Henceforth, we propose effect of HT on IH prevention could be further elucidated through in vivo and ex vivo model.
    Matched MeSH terms: Endothelial Cells
  8. Fulltext Over-expression of Nicotinamide phosphoribosyltransferase in mouse cells confers protective effect against oxidative and ER stress-induced premature senescence
    Nuriliani A, Nakahata Y, Ahmed R, Khaidizar FD, Matsui T, Bessho Y
    Genes Cells, 2020 Aug;25(8):593-602.
    PMID: 32533606 DOI: 10.1111/gtc.12794
    A main feature of aged organisms is the accumulation of senescent cells. Accumulated senescent cells, especially stress-induced premature senescent cells, in aged organisms lead to the decline of the regenerative potential and function of tissues. We recently reported that the over-expression of NAMPT, which is the rate-limiting enzyme in mammalian NAD+ salvage pathway, delays replicative senescence in vitro. However, whether Nampt-overexpressing cells are tolerant of stress-induced premature senescence remains unknown. Here, we show that primary mouse embryonic fibroblasts derived from Nampt-overexpressing transgenic mice (Nampt Tg-MEF cells) possess resistance against stress-induced premature senescence in vitro. We found that higher oxidative or endoplasmic reticulum (ER) stress is required to induce premature senescence in Nampt Tg-MEF cells compared to wild-type cells. Moreover, we found that Nampt Tg-MEF cells show acute expression of unfolded protein response (UPR)-related genes, which in turn would have helped to restore proteostasis and avoid cellular senescence. Our results demonstrate that NAMPT/NAD+ axis functions to protect cells not only from replicative senescence, but also from stress-induced premature senescence in vitro. We anticipate that in vivo activation of NAMPT activity or increment of NAD+ would protect tissues from the accumulation of premature senescent cells, thereby maintaining healthy aging.
    Matched MeSH terms: Cells, Cultured
  9. Comparative Neuroprotective, Anti-Inflammatory and Neurite Outgrowth Activities of Extracts of King Oyster Mushroom, Pleurotus eryngii (Agaricomycetes)
    Kushairi N, Phan CW, Sabaratnam V, Vidyadaran S, Naidu M, David P
    Int J Med Mushrooms, 2020;22(12):1171-1181.
    PMID: 33463934 DOI: 10.1615/IntJMedMushrooms.2020036938
    Pleurotus eryngii (king oyster mushroom) is a renowned culinary mushroom with various medicinal properties that may be beneficial for health maintenance and disease prevention. However, its effect on the nervous system remains elusive. In this study, hot water (PE-HWA) and ethanol (PE-ETH) extracts of P. eryngii were investigated and compared for their neuroprotective, anti-inflammatory, and neurite outgrowth activities in vitro. Based on the results, both extracts up to 400 μg/mL were nontoxic to PC12 cells and BV2 microglia (p > 0.05). Treatment with 250 μM hydrogen peroxide (H2O2) markedly (p < 0.0001) reduced the PC12 cell viability to 67.74 ± 6.47%. Coincubation with 200 μg/mL and 400 μg/mL of PE-ETH dose-dependently increased the cell viability to 85.34 ± 1.91% (p < 0.001) and 98.37 ± 6.42% (p < 0.0001) respectively, while PE-HWA showed no activity. Nitric oxide (NO) released by BV2 microglia was notably (p < 0.0001) increased by 1 μg/mL lipopolysaccharides (LPS) from 7.46 ± 0.73 μM to 80.00 ± 3.78 μM indicating an inflammatory reaction. However, coincubation with 200 and 400 μg/mL of PE-ETH significantly (p < 0.0001) reduced the NO level to 58.57 ± 6.19 μM and 52.86 ± 3.43 μM respectively, while PE-HWA was noneffective. PE-ETH and PE-HWA at 40 μg/mL significantly increased the neurite-bearing cells from 4.70 ± 3.36% to 13.12 ± 2.82% (p < 0.01) and 20.93 ± 5.37% (p < 0.0001) respectively. Pleurotus eryngii, particularly the ethanol extract (PE-ETH) and its potentially bioactive compounds, could be explored as a neurohealth promoting agent, due to its collective neuroprotective, anti-inflammatory, and neurite outgrowth activities.
    Matched MeSH terms: PC12 Cells
  10. Diversity of influenza A viruses retrieved from respiratory disease outbreaks and subclinically infected herds in Spain (2017-2019)
    Sosa Portugal S, Cortey M, Tello M, Casanovas C, Mesonero-Escuredo S, Barrabés S, et al.
    Transbound Emerg Dis, 2021 Mar;68(2):519-530.
    PMID: 32619306 DOI: 10.1111/tbed.13709
    The present study was aimed to assess the diversity of influenza A viruses (IAV) circulating in pig farms in the Iberian Peninsula. The study included two different situations: farms suffering respiratory disease outbreaks compatible with IAV (n = 211) and randomly selected farms without overt respiratory disease (n = 19). Initially, the presence of IAV and lineage determination was assessed by qRT-PCR using nasal swabs. IAV was confirmed in 145 outbreaks (68.7%), mostly in nurseries (53/145; 36.5%). Subtyping by RT-qPCR was possible in 94 of those cases being H1avN2hu (33.6%), H1avN1av (24.3%) and H1huN2hu (18.7%), the most common lineages. H3huN2hu and H1pdmN1pdm represented 7.5% and 6.5% of the cases, respectively. As for the randomly selected farms, 15/19 (78.9%) were positive for IAV. Again, the virus was mostly found in nurseries and H1avN2hu was the predominant lineage. Virus isolation in MDCK cells was attempted from positive cases. Sixty of the isolates were fully sequenced with Illumina MiSeq®. Within those 60 isolates, the most frequent genotypes had internal genes of avian origin, and these were D (19/60; 31.7%) and A (11/60; 18.3%), H1avN2hu and H1avN1av, respectively. In addition, seven previously unreported genotypes were identified. In two samples, more than one H or N were found and it was not possible to precisely establish their genotypes. A great diversity was observed in the phylogenetic analysis. Notably, four H3 sequences clustered with human isolates from 2004-05 (Malaysia and Denmark) that were considered uncommon in pigs. Overall, this study indicates that IAV is a very common agent in respiratory disease outbreaks in Spanish pig farms. The genetic diversity of this virus is continuously expanding with clear changes in the predominant subtypes and lineages in relatively short periods of time. The current genotyping scheme has to be enlarged to include the new genotypes that could be found in the future.
    Matched MeSH terms: Madin Darby Canine Kidney Cells
  11. Identification of a target protein of Hydra actinoporin-like toxin-1 (HALT-1) using GST affinity purification and SILAC-based quantitative proteomics
    Ameirika, Sha HX, Hwang JS
    Toxicon, 2017 Jul;133:153-161.
    PMID: 28478056 DOI: 10.1016/j.toxicon.2017.05.007
    Hydra actinoporin-like toxin-1 (HALT-1) is a 20.8 kDa pore-forming toxin isolated from Hydra magnipapillata. HALT-1 shares structural similarity with actinoporins, a family that is well known for its haemolytic and cytolytic activity. However, the precise pore-forming mechanism of HALT-1 remains an open question since little is known about the specific target binding for HALT-1. For this reason, a comprehensive proteomic analysis was performed using affinity purification and SILAC-based mass spectrometry to identify potential protein-protein interactions between mammalian HeLa cell surface proteins and HALT-1. A total of 4 mammalian proteins was identified, of which only folate receptor alpha was further verified by ELISA. Our preliminary results highlight an alternative-binding mode of HALT-1 to the human plasma membrane. This is the first evidence showing that HALT-1, an actinoporin-like protein, binds to a membrane protein, the folate receptor alpha. This study would advance our understanding of the molecular basis of toxicity of pore-forming toxins and provide new insights in the production of more potent inhibitors for the toxin-membrane receptor interactions.
    Matched MeSH terms: HeLa Cells
  12. Fulltext Gold Nanoparticle-Conjugated Cinnamic Acid Exhibits Antiacanthamoebic and Antibacterial Properties
    Anwar A, Siddiqui R, Shah MR, Khan NA
    Antimicrob Agents Chemother, 2018 09;62(9).
    PMID: 29967024 DOI: 10.1128/AAC.00630-18
    trans-Cinnamic acid (CA) is a natural organic compound. Using amoebicidal assays, for the first time we showed that CA affected the viability of the protist pathogen Acanthamoeba castellanii Conjugation with gold nanoparticles (AuNPs) enhanced the antiamoebic effects of CA. CA-coated AuNPs (CA-AuNPs) also exhibited significant excystation and encystation activity, compared to CA and AuNPs alone. Pretreatment of amoebae with CA-AuNPs inhibited A. castellanii-mediated host cell cytotoxicity. Moreover, CA-AuNPs exhibited potent effects against methicillin-resistant Staphylococcus aureus and neuropathogenic Escherichia coli K1 and protected host cells against bacteria-mediated host cell death.
    Matched MeSH terms: HeLa Cells
  13. Potential anticancer activity of protocatechuic acid loaded in montmorillonite/Fe3O4 nanocomposites stabilized by seaweed Kappaphycus alvarezii
    Yew YP, Shameli K, Mohamad SEB, Nagao Y, Teow SY, Lee KX, et al.
    Int J Pharm, 2019 Dec 15;572:118743.
    PMID: 31705969 DOI: 10.1016/j.ijpharm.2019.118743
    Superparamagnetic magnetite nanocomposites (Fe3O4-NCs) were successfully synthesized, which comprised of montmorillonite (MMT) as matrix support, Kappaphycus alvarezii (SW) as bio-stabilizer and Fe3O4 as filler in the composites to form MMT/SW/Fe3O4-NCs. Nanocomposite with 0.5 g Fe3O4 (MMT/SW/0.5Fe3O4) was selected for anticancer activity study because it revealed high crystallinity, particle size of 7.2 ± 1.7 nm with majority of spherical shape, and Ms = 5.85 emu/g with negligible coercivity. Drug loading and release studies were carried out using protocatechuic acid (PCA) as the model for anticancer drug, which showed 19% and 87% of PCA release in pH 7.4 and 4.8, respectively. Monolayer anticancer assay showed that PCA-loaded MMT/SW/Fe3O4 (MMT/SW/Fe3O4-PCA) had selectivity towards HCT116 (colorectal cancer cell line). Although MMT/SW/Fe3O4-PCA (0.64 mg/mL) showed higher IC50 than PCA (0.148 mg/mL) and MMT/SW/Fe3O4 (0.306 mg/mL, MMT/SW/Fe3O4-PCA showed more effective killing towards tumour spheroid model generated from HCT116. The IC50 for MMT/SW/Fe3O4-PCA, MMT/SW/Fe3O4 and PCA were 0.132, 0.23 and 0.55 mg/mL, respectively. This suggests the improved penetration efficiency and drug release of MMT/SW/Fe3O4-PCA towards HCT116 spheroids. Moreover, concentration that lower than 2 mg/mL MMT/SW/Fe3O4-PCA did not result any hemolysis in human blood, which suggests them to be ideal for intravenous injection. This study highlights the potential of MMT/SW/Fe3O4-NCs as drug delivery agent.
    Matched MeSH terms: HCT116 Cells
  14. Evaluation of metabolomics behavior of human colon cancer HT29 cell lines treated with ionic liquid graviola fruit pulp extract
    Daddiouaissa D, Amid A, Abdullah Sani MS, Elnour AAM
    J Ethnopharmacol, 2021 Apr 24;270:113813.
    PMID: 33444719 DOI: 10.1016/j.jep.2021.113813
    ETHNOPHARMACOLOGICAL RELEVANCE: Medicinal plants have been used by indigenous people across the world for centuries to help individuals preserve their wellbeing and cure diseases. Annona muricata L. (Graviola) which is belonging to the Annonaceae family has been traditionally used due to its medicinal abilities including antimicrobial, anti-inflammatory, antioxidant and cancer cell growth inhibition. Graviola is claimed to be a potential antitumor due to its selective cytotoxicity against several cancer cell lines. However, the metabolic mechanism information underlying the anticancer activity remains limited.

    AIM OF THE STUDY: This study aimed to investigate the effect of ionic liquid-Graviola fruit pulp extract (IL-GPE) on the metabolomics behavior of colon cancer (HT29) by using an untargeted GC-TOFMS-based metabolic profiling.

    MATERIALS AND METHODS: Multivariate data analysis was used to determine the metabolic profiling, and the ingenuity pathway analysis (IPA) was used to predict the altered canonical pathways after treating the HT29 cells with crude IL-GPE and Taxol (positive control).

    RESULTS: The principal components analysis (PCA) identified 44 metabolites with the most reliable factor loading, and the cluster analysis (CA) separated three groups of metabolites: metabolites specific to the non-treated HT29 cells, metabolites specific to the treated HT29 cells with the crude IL-GPE and metabolites specific to Taxol treatment. Pathway analysis of metabolomic profiles revealed an alteration of many metabolic pathways, including amino acid metabolism, aerobic glycolysis, urea cycle and ketone bodies metabolism that contribute to energy metabolism and cancer cell proliferation.

    CONCLUSION: The crude IL-GPE can be one of the promising anticancer agents due to its selective inhibition of energy metabolism and cancer cell proliferation.

    Matched MeSH terms: HT29 Cells
  15. Fulltext In vitro Anticancer Effects of Vernonia amygdalina Leaf Extract and Green-Synthesised Silver Nanoparticles
    Joseph J, Khor KZ, Moses EJ, Lim V, Aziz MY, Abdul Samad N
    Int J Nanomedicine, 2021;16:3599-3612.
    PMID: 34079252 DOI: 10.2147/IJN.S303921
    Purpose: Vernonia amygdalina (VA) is a traditional African herbal medicine that has been reported to possess anticancer properties. However, the anticancer properties of VA silver nanoparticles have not been studied. The aim of the study was to examine and evaluate the anticancer activities of VA leaf extracts and VA silver nanoparticles on the human breast cancer cell line, MCF-7.

    Methods: VA leaves were extracted using sequential extraction assisted with ultrasound using three different solvents: ethanol, 50% ethanol, and deionized water. The silver nanoparticles were synthesised with VA aqueous extract.

    Results: The ethanol extract and VA silver nanoparticles inhibit MCF-7 cell proliferation with an average half-maximal inhibitory concentration (IC50) value of 67µg/mL and 6.11µg/mL, respectively, after 72 hours of treatment. The ethanol extract and VA silver nanoparticles also caused G1 phase cell cycle arrest, induced apoptosis and nuclear fragmentation in MCF-7 cells.

    Conclusion: VA ethanol extracts and VA silver nanoparticles decreased the cell viability in MCF-7 cells in a time and dose-dependent manner by inducing apoptosis and causing DNA damage. Further research is needed to elucidate the mechanism of action of VA leaf extracts and VA silver nanoparticles. This study is the first to report on the anticancer activity of VA silver nanoparticles in MCF-7 cells.

    Matched MeSH terms: MCF-7 Cells
  16. Genes associated with amyloid-beta-induced inflammasome-mediated neuronal death identified using functional gene trap mutagenesis approach
    Yap JKY, Pickard BS, Gan SY, Chan EWL
    Int J Biochem Cell Biol, 2021 07;136:106014.
    PMID: 34022435 DOI: 10.1016/j.biocel.2021.106014
    Alzheimer's disease is an irreversible neurodegenerative disease, which accounts for most dementia cases. Neuroinflammation is increasingly recognised for its roles in Alzheimer's disease pathogenesis which, in part, links amyloid-beta to neuronal death. Neuroinflammatory signalling can be exhibited by neurons themselves, potentially leading to widespread neuronal cell death, although neuroinflammation is commonly associated with glial cells. The presence of the inflammasomes such as nucleotide-binding leucine-rich repeat receptors protein 1 in neurons accelerates amyloid-beta -induced neuroinflammation and has been shown to trigger neuronal pyroptosis in murine Alzheimer's disease models. However, the pathways involved in amyloid-beta activation of inflammasomes have yet to be elucidated. In this study, a gene trap mutagenesis approach was utilised to resolve the genes functionally involved in inflammasome signalling within neurons, and the mechanism behind amyloid-beta-induced neuronal death. The results indicate that amyloid-beta significantly accelerated neuroinflammatory cell death in the presence of a primed inflammasome (the NLR family pyrin domain-containing 1). The mutagenesis screen discovered the atypical mitochondrial Ras homolog family member T1 as a significant contributor to amyloid-beta-induced inflammasome -mediated neuronal death. The mutagenesis screen also identified two genes involved in transforming growth factor beta signalling, namely Transforming Growth Factor Beta Receptor 1 and SNW domain containing 1. Additionally, a gene associated with cytoskeletal reorganisation, SLIT-ROBO Rho GTPase Activating Protein 3 was found to be neuroprotective. In conclusion, these genes could play important roles in inflammasome signalling in neurons, which makes them promising therapeutic targets for future drug development against neuroinflammation in Alzheimer's disease.
    Matched MeSH terms: Tumor Cells, Cultured
  17. Fulltext Experimental Phage Therapy for Burkholderia pseudomallei Infection
    Guang-Han O, Leang-Chung C, Vellasamy KM, Mariappan V, Li-Yen C, Vadivelu J
    PLoS One, 2016;11(7):e0158213.
    PMID: 27387381 DOI: 10.1371/journal.pone.0158213
    Burkholderia pseudomallei is an intracellular Gram-negative bacterial pathogen intrinsically resistant to a variety of antibiotics. Phages have been developed for use as an alternative treatment therapy, particularly for bacterial infections that do not respond to conventional antibiotics. In this study, we investigated the use of phages to treat cells infected with B. pseudomallei. Phage C34 isolated from seawater was purified and characterised on the basis of its host range and morphology using transmission electron microscopy (TEM). Phage C34 was able to lyse 39.5% of B. pseudomallei clinical strains. Due to the presence of contractile tail, phage C34 is classified as a member of the family Myoviridae, a tailed double-stranded DNA virus. When 2 × 105 A549 cells were exposed to 2 × 107 PFU of phage C34, 24 hours prior to infection with 2 × 106 CFU of B. pseudomallei, it was found that the survivability of the cells increased to 41.6 ± 6.8% as compared to 22.8 ± 6.0% in untreated control. Additionally, application of phage successfully rescued 33.3% of mice infected with B. pseudomallei and significantly reduced the bacterial load in the spleen of the phage-treated mice. These findings indicate that phage can be a potential antimicrobial agent for B. pseudomallei infections.
    Matched MeSH terms: A549 Cells
  18. Fulltext Studying neuroprotective effect of Atorvastatin as a small molecule drug on high glucose-induced neurotoxicity in undifferentiated PC12 cells: role of NADPH oxidase
    Rayegan S, Dehpour AR, Sharifi AM
    Metab Brain Dis, 2017 02;32(1):41-49.
    PMID: 27476541 DOI: 10.1007/s11011-016-9883-1
    Overproduction of reactive oxygen species (ROS) by NADPH oxidase (NOX) activation has been considered the essential mechanism induced by hyperglycemia in various tissues. However, there is no comprehensive study on the role of NOXs in high glucose (HG)-induced toxic effect in neural tissues. Recently, a therapeutic strategy in oxidative related pathologies has been introduced by blocking the undesirable actions of NOX enzymes by small molecules. The protective roles of Statins in ameliorating oxidative stress by NOX inhibition have been shown in some tissues except neural. We hypothesized then, that different NOXs may have role in HG-induced neural cell injury. Furthermore, we postulate that Atorvastatin as a small molecule may modulate this NOXs activity to protect neural cells. Undifferentiated PC12 cells were treated with HG (140 mM/24 h) in the presence and absence of Atorvastatin (1 μM/96 h). The cell viability was measured by MTT assay and the gene and protein expressions profile of NOX (1-4) were determined by RT-PCR and western blotting, respectively. Levels of ROS and malondialdehyde (MDA) were also evaluated. Gene and protein expression levels of NOX (1-4) and consequently ROS and MDA levels were elevated in HG-treated PC12 cells. Atorvastatin could significantly decrease HG-induced NOXs, ROS and MDA elevation and improve impaired cell viability. It can be concluded that HG could elevate NOXs activity, ROS and MDA levels in neural tissues and Atorvastatin as a small molecule NOX inhibitor drug may prevent and delay diabetic complications, particularly neuropathy.
    Matched MeSH terms: PC12 Cells
  19. Synthesis, in vitro α-glucosidase inhibitory activity and molecular docking studies of new thiazole derivatives
    Khan KM, Qurban S, Salar U, Taha M, Hussain S, Perveen S, et al.
    Bioorg Chem, 2016 10;68:245-58.
    PMID: 27592296 DOI: 10.1016/j.bioorg.2016.08.010
    Current study based on the synthesis of new thiazole derivatives via "one pot" multicomponent reaction, evaluation of their in vitro α-glucosidase inhibitory activities, and in silico studies. All synthetic compounds were fully characterized by (1)H NMR, (13)C NMR and EIMS. CHN analysis was also performed. These newly synthesized compounds showed activities in the range of IC50=9.06±0.10-82.50±1.70μM as compared to standard acarbose (IC50=38.25±0.12μM). It is worth mentioning that most of the compounds such as 1 (IC50=23.60±0.39μM), 2 (IC50=22.70±0.60μM), 3 (IC50=22.40±0.32μM), 4 (IC50=26.5±0.40μM), 6 (IC50=34.60±0.60μM), 7 (IC50=26.20±0.43μM), 8 (IC50=14.06±0.18μM), 9 (IC50=17.60±0.28μM), 10 (IC50=27.16±0.41μM), 11 (IC50=19.16±0.19μM), 12 (IC50=9.06±0.10μM), 13 (IC50=12.80±0.21μM), 14 (IC50=11.94±0.18μM), 15 (IC50=16.90±0.20μM), 16 (IC50=12.60±0.14μM), 17 (IC50=16.30±0.29μM), and 18 (IC50=32.60±0.61μM) exhibited potent inhibitory potential. Molecular docking study was performed in order to understand the molecular interactions between the molecule and enzyme. Newly identified α-glucosidase inhibitors except few were found to be completely non-toxic.
    Matched MeSH terms: 3T3 Cells
  20. Fulltext The immunologic properties of undifferentiated stem cells from human exfoliated deciduous teeth (SHED) and its potential application in bone regeneration
    Nurul, A.A., Tan, S.J., Asiah, A.B., Norliana, G., Nor Shamsuria, O., Nurul, A.S.
    International Medical Journal Malaysia, 2013;12(1):19-26.
    MyJurnal
    Introduction: Stem cells from human exfoliated deciduous teeth (SHED) are highly proliferative, clonogenic cells capable of differentiating into osteoblasts and inducing bone formation. It is a potential alternative for stem cell bone regeneration therapy. However, stem cell therapy carries the risk of immune rejection mediated by inflammatory cytokines of the human defense system. Objective: This preliminary research studies the interaction between SHED and the immune system by determining the inflammatory cytokines profile and osteogenic potential of SHED. Methods: Human fetal osteoblasts (hFOb) cell line and isolated SHED were cultured and total RNA was extracted, followed by reverse transcription cDNA synthesis. Semi-quantitative reverse transcription PCR and Multiplex PCR were performed to detect the expression levels of OPG/RANKL and TNF-α, IL-1β, IL-6, IL-8 and TGF-β in both cell types. Results: Analysis showed that SHED expressed significantly lower amounts of IL-1β, IL-6, and IL-8 compared to hFOB. IL-1β is a potent bone-resorbing factor, while IL-6 and IL-8 induce osteoclastogenesis and osteolysis respectively. SHED did not express TNF-α which stimulates osteoclastic activity. SHED demonstrated high OPG/RANKL ratio, in contrast with that of marrow stem cells described in previous studies. Our findings suggest that SHED may have improved immunomodulatory profile in terms of promoting relatively lower inflammatory reaction during transplant and enhancing bone regeneration. Conclusion: SHED has a potential to be a good source of osteoblasts for bone regeneration therapy. Further studies on the immunomodulatory properties of SHED-derived osteoblasts are necessary to enable stem cell therapy in immunocompetent hosts.
    Matched MeSH terms: Stem Cells
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