Displaying publications 1 - 20 of 55 in total

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  1. Nam HY, Pingguan-Murphy B, Abbas AA, Merican AM, Kamarul T
    Stem Cells Int, 2019;2019:9723025.
    PMID: 30918524 DOI: 10.1155/2019/9723025
    The present study was conducted to establish the amount of mechanical strain (uniaxial cyclic stretching) required to provide optimal tenogenic differentiation expression in human mesenchymal stromal cells (hMSCs) in vitro, in view of its potential application for tendon maintenance and regeneration. Methods. In the present study, hMSCs were subjected to 1 Hz uniaxial cyclic stretching for 6, 24, 48, and 72 hours; and were compared to unstretched cells. Changes in cell morphology were observed under light and atomic force microscopy. The tenogenic, osteogenic, adipogenic, and chondrogenic differentiation potential of hMSCs were evaluated using biochemical assays, extracellular matrix expressions, and selected mesenchyme gene expression markers; and were compared to primary tenocytes. Results. Cells subjected to loading displayed cytoskeletal coarsening, longer actin stress fiber, and higher cell stiffness as early as 6 hours. At 8% and 12% strains, an increase in collagen I, collagen III, fibronectin, and N-cadherin production was observed. Tenogenic gene expressions were highly expressed (p < 0.05) at 8% (highest) and 12%, both comparable to tenocytes. In contrast, the osteoblastic, chondrogenic, and adipogenic marker genes appeared to be downregulated. Conclusion. Our study suggests that mechanical loading at 8% strain and 1 Hz provides exclusive tenogenic differentiation; and produced comparable protein and gene expression to primary tenocytes.
    Matched MeSH terms: Actins
  2. Tan JJ, Azmi SM, Yong YK, Cheah HL, Lim V, Sandai D, et al.
    PLoS One, 2014;9(5):e96800.
    PMID: 24802273 DOI: 10.1371/journal.pone.0096800
    Stem cells with enhanced resistance to oxidative stress after in vitro expansion have been shown to have improved engraftment and regenerative capacities. Such cells can be generated by preconditioning them with exposure to an antioxidant. In this study we evaluated the effects of Tualang honey (TH), an antioxidant-containing honey, on human corneal epithelial progenitor (HCEP) cells in culture. Cytotoxicity, gene expression, migration, and cellular resistance to oxidative stress were evaluated. Immunofluorescence staining revealed that HCEP cells were holoclonal and expressed epithelial stem cell marker p63 without corneal cytokeratin 3. Cell viability remained unchanged after cells were cultured with 0.004, 0.04, and 0.4% TH in the medium, but it was significantly reduced when the concentration was increased to 3.33%. Cell migration, tested using scratch migration assay, was significantly enhanced when cells were cultured with TH at 0.04% and 0.4%. We also found that TH has hydrogen peroxide (H2O2) scavenging ability, although a trace level of H2O2 was detected in the honey in its native form. Preconditioning HCEP cells with 0.4% TH for 48 h showed better survival following H2O2-induced oxidative stress at 50 µM than untreated group, with a significantly lower number of dead cells (15.3 ± 0.4%) were observed compared to the untreated population (20.5 ± 0.9%, p<0.01). Both TH and ascorbic acid improved HCEP viability following induction of 100 µM H2O2, but the benefit was greater with TH treatment than with ascorbic acid. However, no significant advantage was demonstrated using 5-hydroxymethyl-2-furancarboxaldehyde, a compound that was found abundant in TH using GC/MS analysis. This suggests that the cellular anti-oxidative capacity in HCEP cells was augmented by native TH and was attributed to its antioxidant properties. In conclusion, TH possesses antioxidant properties and can improve cell migration and cellular resistance to oxidative stress in HCEP cells in vitro.
    Matched MeSH terms: Actins/genetics; Actins/metabolism
  3. Sadat Mohajer F, Parvizpour S, Razmara J, Shahir Shamsir M
    J Biomol Struct Dyn, 2019 Feb;37(2):372-382.
    PMID: 29338614 DOI: 10.1080/07391102.2018.1427630
    Congenital myopathy is a broad category of muscular diseases with symptoms appearing at the time of birth. One type of congenital myopathy is Congenital Fiber Type Disproportion (CFTD), a severely debilitating disease. The G48D and G48C mutations in the D-loop and the actin-myosin interface are the two causes of CFTD. These mutations have been shown to significantly affect the structure and function of muscle fibers. To the author's knowledge, the effects of these mutations have not yet been studied. In this work, the power stroke structure of the head domain of myosin and the wild and mutated types of actin were modeled. Then, a MD simulation was run for the modeled structures to study the effects of these mutations on the structure, function, and molecular dynamics of actin. The wild and mutated actins docked with myosin showed differences in hydrogen bonding patterns, free binding energies, and hydrogen bond occupation frequencies. The G48D and G48C mutations significantly impacted the conformation of D-loops because of their larger size compared to Glycine and their ability to interfere with the polarity or hydrophobicity of this neutralized and hydrophobic loop. Therefore, the mutated loops were unable to fit properly into the hydrophobic groove of the adjacent G-actin. The abnormal structure of D-loops seems to result in the abnormal assembly of F-actins, giving rise to the symptoms of CFTD. It was also noted that G48C and G48D did not form hydrogen bonds with myosin in the residue 48 location. Nevertheless, in this case, muscles are unable to contract properly due to muscle atrophy.
    Matched MeSH terms: Actins/genetics*; Actins/chemistry*
  4. Choo KK, Chong PP, Ho AS, Yong PV
    Eur J Clin Microbiol Infect Dis, 2015 Dec;34(12):2421-7.
    PMID: 26463450 DOI: 10.1007/s10096-015-2497-4
    The purpose of this investigation was to characterise the interactions of Cryptococcus neoformans with mammalian host alveolar epithelial cells and alveolar macrophages, with emphasis on the roles of the cryptococcal capsule and the host cell cytoskeletons. The adherence and internalisation of C. neoformans into mammalian lung cells and the roles of host cell cytoskeletons in host-pathogen interactions were studied using in vitro models coupled with a differential fluorescence assay, fluorescence staining, immunofluorescence and drug inhibition of actin and microtubule polymerisation. Under conditions devoid of opsonin and macrophage activation, C. neoformans has a high affinity towards MH-S alveolar macrophages, yet associated poorly to A549 alveolar epithelial cells. Acapsular C. neoformans adhered to and internalised into the mammalian cells more effectively compared to encapsulated cryptococci. Acapsular C. neoformans induced prominent actin reorganisation at the host-pathogen interface in MH-S alveolar macrophages, but minimally affected actin reorganisation in A549 alveolar epithelial cells. Acapsular C. neoformans also induced localisation of microtubules to internalised cryptococci in MH-S cells. Drug inhibition of actin and microtubule polymerisation both reduced the association of acapsular C. neoformans to alveolar macrophages. The current study visualises and confirms the interactions of C. neoformans with mammalian alveolar cells during the establishment of infection in the lungs. The acapsular form of C. neoformans effectively adhered to and internalised into alveolar macrophages by inducing localised actin reorganisation, relying on the host's actin and microtubule activities.
    Matched MeSH terms: Actins
  5. Paramanantham Y, B M Said NA, Mun KS
    Malays J Pathol, 2023 Apr;45(1):19-29.
    PMID: 37119243
    INTRODUCTION: Although epithelial-mesenchymal transition (EMT) and p53 have been established to play a pivotal role in the aggressiveness of muscle-invasive bladder cancer (MIBC), its pathological correlation to cisplatin treatment in the Malaysian patient cohort is lacking. This study aimed to evaluate the association of EMT markers, e-cadherin, vimentin and actin, as well as tumour suppressor gene, p53, in cisplatin-receiving MIBC patients.

    MATERIALS AND METHODS: Formalin-fixed paraffinembedded (FFPE) blocks of muscle-invasive bladder cancer patients receiving cisplatin-based chemotherapy between January 2010 to December 2020 were traced. Immunohistochemistry staining was performed on traced blocks using antibodies to e-cadherin, vimentin and actin, and p53.

    RESULTS: p53 and e-cadherin were stained positive in most cases (p=0.515 and 0.242 respectively), although e-cadherin showed stronger positive expression in pre-cisplatin receiving MIBC cases. All the cases stained negative for actin and vimentin except for faint staining observed in one pre-cisplatin case.

    CONCLUSION: Although this study does not show a significant correlation between EMT markers and p53 with cisplatin-responsiveness in MIBC patients, the results serve as preliminary findings on the heterogeneous outcomes of molecular staining in the Malaysian MIBC patient cohort.

    Matched MeSH terms: Actins/metabolism
  6. Dugina VB, Shagieva GS, Shakhov AS, Alieva IB
    Int J Mol Sci, 2021 Jul 22;22(15).
    PMID: 34360602 DOI: 10.3390/ijms22157836
    The primary function of the endothelial cells (EC) lining the inner surface of all vessels is to regulate permeability of vascular walls and to control exchange between circulating blood and tissue fluids of organs. The EC actin cytoskeleton plays a crucial role in maintaining endothelial barrier function. Actin cytoskeleton reorganization result in EC contraction and provides a structural basis for the increase in vascular permeability, which is typical for many diseases. Actin cytoskeleton in non-muscle cells presented two actin isoforms: non-muscle β-cytoplasmic and γ-cytoplasmic actins (β-actins and γ-actins), which are encoded by ACTB and ACTG1 genes, respectively. They are ubiquitously expressed in the different cells in vivo and in vitro and the β/γ-actin ratio depends on the cell type. Both cytoplasmic actins are essential for cell survival, but they perform various functions in the interphase and cell division and play different roles in neoplastic transformation. In this review, we briefly summarize the research results of recent years and consider the features of the cytoplasmic actins: The spatial organization in close connection with their functional activity in different cell types by focusing on endothelial cells.
    Matched MeSH terms: Actins/metabolism*
  7. Zhou C, Wu X, Pan D, Xia Q, Sun Y, Geng F, et al.
    Food Chem, 2024 Mar 15;436:137711.
    PMID: 37839122 DOI: 10.1016/j.foodchem.2023.137711
    To understand the mechanism of co-inoculation of Staphylococcus xylosus and Staphylococcus vitulinus (SX & SV) on structural protein degradation and taste enhancement of dry-cured bacon, protease activities, protein degradation, surface morphology of proteins and taste parameters of dry-cured bacon with Staphylococcus inoculation were investigated. The dry-cured bacon with co-inoculation of Staphylococcus xylosus and Staphylococcus vitulinus showed the best taste attributes. High residual activities in cathepsin B + L (more than 1.6-fold) and alanyl aminopeptidase (more than 1.4-fold) accelerated structural protein degradation in SX & SV. 32 down-regulated proteins were identified in SX & SV by TMT-labeled quantitative proteomic compared with control group; myosin and actin showed the most intense response to the accumulation of sweet and umami amino acids, and atomic force microscopy confirmed structural proteins breakdown by morphological changes. The accumulation of glutamic acid, alanine and lysine was mainly responsible for taste improvement of dry-cured bacon with Staphylococcus co-inoculation.
    Matched MeSH terms: Actins
  8. Vadivelu J, Vellasamy KM, Thimma J, Mariappan V, Kang WT, Choh LC, et al.
    PLoS Negl Trop Dis, 2017 01;11(1):e0005241.
    PMID: 28045926 DOI: 10.1371/journal.pntd.0005241
    BACKGROUND: During infection, successful bacterial clearance is achieved via the host immune system acting in conjunction with appropriate antibiotic therapy. However, it still remains a tip of the iceberg as to where persistent pathogens namely, Burkholderia pseudomallei (B. pseudomallei) reside/hide to escape from host immune sensors and antimicrobial pressure.

    METHODS: We used transmission electron microscopy (TEM) to investigate post-mortem tissue sections of patients with clinical melioidosis to identify the localisation of a recently identified gut microbiome, B. pseudomallei within host cells. The intranuclear presence of B. pseudomallei was confirmed using transmission electron microscopy (TEM) of experimentally infected guinea pig spleen tissues and Live Z-stack, and ImageJ analysis of fluorescence microscopy analysis of in vitro infection of A549 human lung epithelial cells.

    RESULTS: TEM investigations revealed intranuclear localization of B. pseudomallei in cells of infected human lung and guinea pig spleen tissues. We also found that B. pseudomallei induced actin polymerization following infection of A549 human lung epithelial cells. Infected A549 lung epithelial cells using 3D-Laser scanning confocal microscopy (LSCM) and immunofluorescence microscopy confirmed the intranuclear localization of B. pseudomallei.

    CONCLUSION: B. pseudomallei was found within the nuclear compartment of host cells. The nucleus may play a role as an occult or transient niche for persistence of intracellular pathogens, potentially leading to recurrrent episodes or recrudescence of infection.

    Matched MeSH terms: Actins/metabolism
  9. Noor Liza Ishak, Primuharsa Putra Sabir Athar Husin, Suria Hayati Md Pauzi, Isa Mohd Rose, Mohd Razif Mohamad Yunus
    MyJurnal
    Solitary fibrous tumours of the head and neck region are
    extremely rare. The clinical diagnosis is often difficult to
    establish, and this lesion may be indistinguishable from other
    soft tissue neoplasms. An 18-year old Chinese gentleman
    presented with a painless right submandibular swelling which
    was increasing in size for eight months. A computed
    tomography scan showed a well-defined solid mass measuring
    about 2.0 x 2.96 cm in the submandibular region. The tumour
    was resected and was confined within its capsule.
    Immunohistochemical staining was strongly positive for CD34,
    CD 99, and vimentin and negative for desmin, smooth muscle
    actin (SMA), cytokeratin, S100 and CD68. The microscopic and
    immunohistochemical profile were compatible with solitary
    fibrous tumour. Distinguishing solitary fibrous tumours from
    various spindle neoplasms can be difficult. In view of the
    resemblance, immunohistochemical staining can help
    differentiate solitary fibrous tumour from spindle neoplasm.
    Matched MeSH terms: Actins
  10. Gholami K, Loh SY, Salleh N, Lam SK, Hoe SZ
    PLoS One, 2017;12(6):e0176368.
    PMID: 28591185 DOI: 10.1371/journal.pone.0176368
    Real-time quantitative PCR (qPCR) is the most reliable and accurate technique for analyses of gene expression. Endogenous reference genes are being used to normalize qPCR data even though their expression may vary under different conditions and in different tissues. Nonetheless, verification of expression of reference genes in selected studied tissue is essential in order to accurately assess the level of expression of target genes of interest. Therefore, in this study, we attempted to examine six commonly used reference genes in order to identify the gene being expressed most constantly under the influence of testosterone in the kidneys and hypothalamus. The reference genes include glyceraldehyde-3-phosphate dehydrogenase (GAPDH), actin beta (ACTB), beta-2 microglobulin (B2m), hypoxanthine phosphoribosyltransferase 1 (HPRT), peptidylprolylisomerase A (Ppia) and hydroxymethylbilane synthase (Hmbs). The cycle threshold (Ct) value for each gene was determined and data obtained were analyzed using the software programs NormFinder, geNorm, BestKeeper, and rank aggregation. Results showed that Hmbs and Ppia genes were the most stably expressed in the hypothalamus. Meanwhile, in kidneys, Hmbs and GAPDH appeared to be the most constant genes. In conclusion, variations in expression levels of reference genes occur in kidneys and hypothalamus under similar conditions; thus, it is important to verify reference gene levels in these tissues prior to commencing any studies.
    Matched MeSH terms: Actins/biosynthesis
  11. Liew JWK, Fong MY, Lau YL
    PeerJ, 2017;5:e3577.
    PMID: 28761783 DOI: 10.7717/peerj.3577
    Quantitative reverse transcription PCR (qRT-PCR) has been an integral part of characterizing the immunity of Anopheles mosquitoes towards Plasmodium invasion. Two anti-Plasmodium factors of Anopheles, thioester-containing protein 1 (TEP1) and nitric oxide synthase (NOS), play a role in the refractoriness of Anopheles towards Plasmodium infection and are generally expressed during infection. However, these are less studied in Anopheles dirus, a dominant malaria vector in Southeast Asia. Furthermore, most studies used a single reference gene for normalization during gene expression analysis without proper validation. This may lead to erroneous quantification of expression levels. Therefore, the present study characterized and investigated the expression profiles of TEP1 and NOS of Anopheles dirus during P. berghei infection. Prior to that, the elongation factor 1-alpha (EF1), actin 1 (Act) and ribosomal protein S7 (S7) genes were validated for their suitability as a set of reference genes. TEP1 and NOS expressions in An. dirus were found to be significantly induced after P. berghei infection.
    Matched MeSH terms: Actins
  12. Khairul Osman, Norashikin Md.Saad, Ezlan Elias, Siti Fatimah Ibrahim, Jamaludin Mohamed, Proomwichit, Proom
    MyJurnal
    A study was conducted to determine the radioprotective effects of Citrullus vulgaris on the lymphocyte sub-membrane particularly the actin layer. A total of 30 adult male Sprague-Dawley rats were divided into three equal groups of positive control, negative control and treatment. The positive and negative control groups were force fed with 40 ml/kg body weight of normal saline while the treatment group received 40 g/kg body weight of fresh juice of C. vulgaris daily. After a week the positive control and treatment groups were irradiated with 90 rad gamma radiation. Viable lymphocytes were determined using propidium iodine and acridine orange stain and observed under a fluorescent microscope. The percentage of viable lymphocytes of the treatment group (71.0%; p = 0.03) was significantly higher than the positive control group. The results showed that C. vulgaris possessed radioprotective effects because the lymphocyte actin was not damaged. The radioprotection effects could be due to the presence of antioxidants in C. vulgaris.
    Matched MeSH terms: Actins
  13. Thent ZC, Froemming GRA, Ismail ABM, Fuad SBSA, Muid S
    Iran J Basic Med Sci, 2020 Sep;23(9):1155-1163.
    PMID: 32963737 DOI: 10.22038/ijbms.2020.45296.10545
    Objectives: Since bisphenol A (BPA) induces bone loss and phytoestrogens enhance the osteoblastogenesis by binding to the non-classical and classical oestrogen receptors, respectively, the present study was aimed to observe the osteoprotective effect of phytoestrogens on BPA-induced osteoblasts in hFOB 1.19 cells.

    Materials and Methods: All groups of hFOB 1.19 cells were induced with 12.5 μg/ml of BPA except the control (Ctrl) group. Meanwhile, treated groups received phytoestrogens; Daidzein (Dz), Genistein (Gt), Equol (Eq) and 17β-oestradiol (Est) in different concentrations for 24 hr duration.

    Results: We found that the protein expression of non-classical oestrogen-related receptor (ERRG) was highly expressed in BPA group, whereas classical oestrogen receptor alpha (ERα) and oestrogen receptor beta (ERβ) were relatively increased with phytoestrogens treatment under BPA exposure. The dense actin cytoskeletal filaments were also observed. qRT-PCR showed up-regulation of mitogen-activated protein kinase 3 (MAPK3) and G protein-coupled receptor 30 (GPR30) expressions; significant down-regulation of ERRG and up-regulation of ERα and ERβ were observed in phytoestrogens-treated cells, which was supported by the increased expressions of oestrogen receptor 1 (ESR1) and oestrogen receptor 2 (ESR2).

    Conclusion: Phytoestrogens improved the deteriorative effect of BPA via down-regulation of ERRG in hFOB 1.19 cells. This study showed that the efficacy of consumption of phytoestrogens in rendering them as potential therapeutic strategy in combating the adverse bone effects of BPA.

    Matched MeSH terms: Actins
  14. Abd Ghafar N, Chua KH, Wan Ngah WZ, Che Hamzah J, Othman F, Abd Rahman R, et al.
    Cell Tissue Bank, 2014 Mar;15(1):25-34.
    PMID: 23292197 DOI: 10.1007/s10561-012-9360-y
    The in vivo quiescent corneal stroma keratocytes need to be transformed to activated state in order to obtain sufficient number of cells either for monolayer evaluation or corneal stroma reconstruction. This study aimed to investigate the phenotypic characterization of corneal stromal cells during culture expansion from the limbal region of the cornea. Isolated corneal keratocytes from limbal tissue of New Zealand White Strain rabbits' corneas (n = 6) were culture expanded until three passages. Keratocytes morphology was examined daily with viability, growth rate, number of cell doubling and population doubling time were recorded at each passage. The expression of collagen type 1, aldehyde dehydrogenase (ALDH), lumican and alpha smooth muscle actin (α-SMA) were detected by RT-PCR. Immunocytochemistry was also used to detect ALDH, α-SMA, collagen type I and Cytokeratin-3 (CK3). Growth kinetic study revealed that the growth rate was low at the initial passage but increase to about two folds with concomitant reduction in population doubling time in later passages. Freshly isolated and cultured keratocytes expressed collagen type 1, ALDH and lumican but α-SMA expression was absent. However, α-SMA was expressed along with the other genes during culture expansion. Keratocytes at P1 expressed all the proteins except CK3. These results suggest that cultured keratocytes maintained most of the gene expression profile of native keratocytes while the emergence of α-SMA in serial passages showed a mix population of various phenotypes. The phenotypic characterization of monolayer keratocytes provides useful information before reconstruction of bioengineered tissue or in vitro pharmaceutical applications.
    Matched MeSH terms: Actins/biosynthesis
  15. Mahmodi F, Kadir JB, Nasehi A, Puteh A, Soleimani N
    Plant Dis, 2013 Nov;97(11):1507.
    PMID: 30708462 DOI: 10.1094/PDIS-03-13-0231-PDN
    At least nine Colletotrichum species, particularly Colletotrichum truncatum, have been recorded on legumes worldwide (1). In June 2010, samples of chickpea leaflets showing leaf spot disease symptoms were collected from experimental farms in Ladang Dua, Selangor state of Malaysia. Tan lesions with darker brown borders were observed on leaflets and were associated with premature leaf drop. Stem lesions initially appeared on the lower parts of stems and later progressed higher in the plant. Lesions often girdled the stem and caused severe dieback. Abundant acervuli developed in the lesions visible as black dots. Foliar lesions were removed, surface sterilized in 1% sodium hypochlorite for 2 min, rinsed twice with distilled water, dried on sterilized tissue paper, plated on PDA plates, and incubated at 25°C (3). Three isolates of the fungus were obtained and identified as C. truncatum on the basis of morphological characteristics (2). The isolates were deposited in the University Putra of Malaysia Culture Collection (UPMCC). Colony characteristics on PDA varied from greyish white to dark in color and exhibited mycelial growth with sparse acervuli. The isolates produced both sclerotia and setae in culture. Conidia (mean ± SD = 22 ± 0.83 × 3.6 ± 0.08 μm, L/W ratio = 6.1) produced in acervuli were falcate, hyaline, and aseptate, with tapering towards the acute and greatly curved apex. The conidial mass color varied from pale buff to saffron. Isolates produced simple to slightly lobed, mainly short clavate appressoria (mean ± SD = 9.60 ± 0.36 × 6.67 ± 0.29 μm, L/W ratio = 1.45). Amplification and sequence analysis of coding and none-coding regions of the ITS-rDNA (GenBank Accession JX971160), actin (JX975392), β-tubulin (KC109495), histone (KC109535), chitin synthase (KC109575), and glyceraldehyde-3-phosphate dehydrogenase (KC109615) obtained from the representative isolate, CTM37, aligned with deposited sequences from GenBank and revealed 99 to 100% sequence identity with C. truncatum strains (AJ301945, KC110827, GQ849442, GU228081, GU228359, and HM131501 from GenBank). Isolate CTM37 was used to test pathogenicity in the greenhouse. Five chickpea seeds of cultivar ILC-1929 were sown per pot in four replications. Ten days after seedling emergence, plants were inoculated with a spore suspension (concentration = 106 conidia ml-1) and check pots were sprayed with distilled water. After inoculation, the plants were covered with plastic bags for 48 h and kept at 28 to 33°C and >90% RH. After incubation, the plastic bags were removed and the plants were placed on greenhouse benches and monitored daily for symptom development (3). One week after inoculation, typical anthracnose symptoms developed on the leaves and stems of inoculated plants including acervuli formation, but not on the checks. A fungus with the same colony and conidial morphology as CTM37 was recovered from the lesions on the inoculated plants. The experiment was repeated twice. The ability to accurately diagnose Colletotrichum species is vital for the implementation of effective disease control and quarantine measures. We believe this is the first report of C. truncatum causing anthracnose on chickpea in Malaysia. References: (1) B. D. Gossen et al. Can. J. Plant Pathol. 31:65, 2009. (2) B. C. Sutton. The Genus Glomerella and its anamorph Colletotrichum. CAB International, Wallingford. UK. 1992. (3) P. P. Than et al. Plant Pathol. 57:562, 2008. ERRATUM: A correction was made to this Disease Note on May 19, 2014. The author N. Soleimani was added.
    Matched MeSH terms: Actins
  16. Thiagarajan S, Arapoc DJ, Husna Shafie N, Keong YY, Bahari H, Adam Z, et al.
    PMID: 30956678 DOI: 10.1155/2019/2821597
    Lung cancer is the leading cause of cancer related deaths worldwide with about 40% occurring in developing countries. The two varieties of Momordica charantia, which are Chinese and Indian bitter melon, have been subjected to antiproliferative activity in human non-small cell lung cells A549. The A549 cells were treated with hot and cold aqueous extraction for both the bitter melon varieties, and the antiproliferative activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The apoptotic mechanism of action on A549 human lung cancer cells was evaluated first morphologically using Hoechst 33358, and cytoskeleton staining using Filamentous-actin (F-actin) cytoskeleton FICT and DAPI followed by caspase-3/7, reactive oxygen species (ROS), and p53 activity. Chinese hot aqueous extraction (CHA) exhibited potent antiproliferative activity against A549 human lung cancer cells. The morphological analysis of mitochondria destruction and the derangement of cytoskeleton showed apoptosis-inducing activity. CHA increased the caspase-3/7 activity by 1.6-fold and the ROS activity by 5-fold. Flow cytometric analysis revealed 34.5% of apoptotic cells significantly (p<0.05) compared to cisplatin-treated A549 human cancer cells. CHA is suggested to induce apoptosis due to their rich bioactive chemical constituents. These findings suggest that the antiproliferative effect of CHA was due to apoptosis via ROS-mediated mitochondria injury.
    Matched MeSH terms: Actins
  17. Yap HYY, Tan NH, Ng ST, Tan CS, Fung SY
    PeerJ, 2018;6:e4940.
    PMID: 29888137 DOI: 10.7717/peerj.4940
    Background: The highly valued medicinal tiger milk mushroom (also known as Lignosus rhinocerus) has the ability to cure numerous ailments. Its anticancer activities are well explored, and recently a partially purified cytotoxic protein fraction termed F5 from the mushroom's sclerotial cold water extract consisting mainly of fungal serine proteases was found to exhibit potent selective cytotoxicity against a human breast adenocarcinoma cell line (MCF7) with IC50 value of 3.00 μg/ml. However, characterization of its cell death-inducing activity has yet to be established.

    Methods: The mechanism involved in the cytotoxic activities of F5 against MCF7 cells was elucidated by flow cytometry-based apoptosis detection, caspases activity measurement, and expression profiling of apoptosis markers by western blotting. Molecular attributes of F5 were further mined from L. rhinocerus's published genome and transcriptome for future exploration.

    Results and Discussion: Apoptosis induction in MCF7 cells by F5 may involve a cross-talk between the extrinsic and intrinsic apoptotic pathways with upregulation of caspase-8 and -9 activities and a marked decrease of Bcl-2. On the other hand, the levels of pro-apoptotic Bax, BID, and cleaved BID were increased accompanied by observable actin cleavage. At gene level, F5 composed of three predicted non-synonymous single nucleotide polymorphisms (T > C) and an alternative 5' splice site.

    Conclusions: Findings from this study provide an advanced framework for further investigations on cancer therapeutics development from L. rhinocerus.

    Matched MeSH terms: Actins
  18. Siar CH, Rahman ZA, Tsujigiwa H, Mohamed Om Alblazi K, Nagatsuka H, Ng KH
    J Oral Pathol Med, 2016 Sep;45(8):591-8.
    PMID: 26752341 DOI: 10.1111/jop.12417
    BACKGROUND: Cell migration and invasion through interstitial tissues are dependent upon several specialized characteristics of the migratory cell notably generation of proteolytic membranous protrusions or invadopodia. Ameloblastoma is a benign odontogenic epithelial neoplasm with a locally infiltrative behaviour. Cortactin and MMT1-MMP are two invadopodia proteins implicated in its local invasiveness. Other invadopodia regulators, namely N-WASP, WIP and Src kinase remain unclarified. This study addresses their roles in ameloblastoma.

    MATERIALS AND METHOD: Eighty-seven paraffin-embedded ameloblastoma cases (20 unicystic, 47 solid/multicystic, 3 desmoplastic and 17 recurrent) were subjected to immunohistochemistry for expression of cortactin, N-WASP, WIP, Src kinase and F-actin, and findings correlated with clinicopathological parameters.

    RESULTS: Invadopodia proteins (except Src kinase) and F-actin were widely detected in ameloblastoma (cortactin: n = 73/87, 83.9%; N-WASP: n = 59/87; 67.8%; WIP: n = 77/87; 88.5%; and F-actin: n = 87/87, 100%). Protein localization was mainly cytoplasmic and/or membranous, and occasionally nuclear for F-actin. Cortactin, which functions as an actin-scaffolding protein, demonstrated significantly higher expression levels within ameloblastoma tumoral epithelium than in stroma (P < 0.05). N-WASP, which coordinates actin polymerization and invadopodia-mediated extracellular matrix degradation, was overexpressed in the solid/multicystic subtype (P < 0.05). WIP, an upstream regulator of N-WASP, and F-actin were significantly upregulated along the tumour invasive front compared to tumour centres (P < 0.05). Except for males with cortactin overexpression, other clinical parameters (age, ethnicity and anatomical site) showed no significant correlations.

    CONCLUSIONS: Present results suggest that local invasiveness of ameloblastoma is dependent upon the migratory potential of its tumour cells as defined by their distribution of cortactin, N-WASP and WIP in correlation with F-actin cytoskeletal dynamics.

    Matched MeSH terms: Actins/analysis; Actins/biosynthesis; Actins/physiology
  19. Hamad Ali Hamad, Cheah, Yoke Kqueen, Nur Fariesha MD Hashim
    MyJurnal
    High invasive cancer cells are thought to recruit specialised actin-rich protrusions for invasion in metastasis process. These protrusions are termed invadopodia. To study invadopodia formation, one of the first challenges faced by researchers has been to optimise the cell line passage number in order to be used for the invadopodia assay. Therefore, this study aims to investigate the effects of the passage number on invadopodia formation in MDA-MB-231 breast cancer cell line. Invadopodia assay was used to achieve the aim of the study. The results provided evidence that invadopodia formation is affected by the high passage number. The cells were also tested with dimethyloxalylglycine (DMOG) a hypoxic mimicking agent which is known to be an invadopodia inducer, the results showed that the cells in low passage number (P7) treated with DMOG increase the cells forming invadopodia, while the cells with high passage number (P35) showed that DMOG fails to stimulate the cells to form invadopodia. Furthermore, the cells with high passage number after passage 15 are starting to lose the ability to degrade the gelatin. In conclusion, this study suggests that only cells with a low passage number, less than passage 15 should be used in the study of invadopodia formation to obtain the results in the search for molecular targets and signaling at invadopodia.
    Matched MeSH terms: Actins
  20. Ng CT, Fong LY, Yong YK, Hakim MN, Ahmad Z
    Cytokine, 2018 11;111:541-550.
    PMID: 29909980 DOI: 10.1016/j.cyto.2018.06.010
    Endothelial barrier dysfunction leads to increased endothelial permeability and is an early step in the development of vascular inflammatory diseases such as atherosclerosis. Interferon-γ (IFN-γ), a proinflammatory cytokine, is known to cause increased endothelial permeability. However, the mechanisms by which IFN-γ disrupts the endothelial barrier have not been clarified. This study aimed to investigate how IFN-γ impairs the endothelial barrier integrity by specifically examining the roles of caldesmon, adherens junctions (AJs) and p38 mitogen-activated protein (MAP) kinase in IFN-γ-induced endothelial barrier dysfunction. IFN-γ exhibited a biphasic effect on caldesmon localization and both the structural organization and protein expression of AJs. In the early phase (4-8 h), IFN-γ induced the formation of peripheral caldesmon bands and discontinuous AJs, while AJ protein expression was unchanged. Interestingly, IFN-γ also stimulated caldesmon phosphorylation, resulting in actin dissociation from caldesmon at 8 h. Conversely, changes seen in the late phase (16-24 h) included cytoplasmic caldesmon dispersal, AJ linearization and junctional area reduction, which were associated with reduced membrane, cytoskeletal and total AJ protein expression. In addition, IFN-γ enhanced myosin binding to caldesmon at 12 h and persisted up to 24 h. Furthermore, inhibition of p38 MAP kinase by SB203580 did not reverse either the early or late phase changes observed. These data suggest that IFN-γ may activate signaling molecules other than p38 MAP kinase. In conclusion, our findings enhance the current understanding of how IFN-γ disrupts endothelial barrier function and reveal potential therapeutic targets, such as caldesmon and AJs, for the treatment of IFN-γ-associated vascular inflammatory diseases.
    Matched MeSH terms: Actins/metabolism
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