Displaying publications 2221 - 2240 of 3312 in total

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  1. Long term maintenance of Toxoplasma gondii (Rh strain) in Vero cell line and use of harvested antigens for immunodiagnosis
    Suresh K, Mak JW, Yong HS
    Southeast Asian J Trop Med Public Health, 1991 Dec;22 Suppl:124-8.
    PMID: 1822869
    Thirty in vitro serial passages of Toxoplasman gondii cultures in Vero cell line performed once in every five days had a mean increase in parasite count of 74.4 +/- 14.8 times from that of initial counts. Long term cultures in Vero cell line did not alter the virulence of the parasite. The good correlation (r = 0.99) between the IFA titer and ELISA OD values using the parasite antigens from in vitro sources indicates that long term maintenance of T. gondii in culture does not affect significantly the ability to recognize antibodies to surface and soluble antigens. The results also show that soluble antigens containing host cells can be directly used for immunodiagnostic purposes without purification. The in vitro maintenance of T. gondii is safer and cheaper when compared to the in vivo method.
    Matched MeSH terms: Vero Cells
  2. Isolation and Characterization of Antimicrobial Peptides Isolated from Brevibacillus halotolerans 7WMA2 for the Activity Against Multidrug-Resistant Pathogens
    Le Han H, Pham PTV, Kim SG, Chan SS, Khoo KS, Chew KW, et al.
    Mol Biotechnol, 2024 Dec;66(12):3618-3627.
    PMID: 38042757 DOI: 10.1007/s12033-023-00963-0
    Multidrug resistance to pathogens has posed a severe threat to public health. The threat could be addressed by antimicrobial peptides (AMPs) with broad-spectrum suppression. In this study, Brevibacillus halotolerans 7WMA2, isolated from marine sediment, produced AMPs against Gram-positive and Gram-negative bacteria. The AMPs were precipitated by ammonium sulfate 30% (w/v) from culture broth and dialyzed by a 1 kDa membrane. Tryptone Soy Agar (TSA) was used for the cultivation and resulted in the largest bacteria-inhibiting zones under aerobic conditions at 25 °C, 48 h. An SDS-PAGE gel overlay test revealed that strain 7WMA2 could produce AMPs of 5-10 kDa and showed no degradation when held at 121 °C for 30 min at a wide pH 2-12 range. The AMPs did not cause toxicity to HeLa cells with concentrations up to 500 µg/mL while increasing the arbitrary unit up to eight times. The study showed that the AMPs produced were unique, with broad-spectrum antimicrobial ability.
    Matched MeSH terms: HeLa Cells
  3. Intrapericardial Administration of Human Pericardial Fluid Cells Improves Cardiac Functions in Rats with Heart Failure
    Xu Y, Zhang X, Fu Z, Dong Y, Yu Y, Liu Y, et al.
    Stem Cells Dev, 2024 Nov;33(21-22):616-629.
    PMID: 39155804 DOI: 10.1089/scd.2024.0072
    Heart failure (HF) is still the main cause of mortality worldwide. This study investigated the characteristics of human pericardial fluid-derived cells (hPFCs) and their effects in treating doxorubicin (DOX)-induced HF rats through intrapericardial injection. hPFCs were isolated from patients who underwent heart transplantation (N = 5). These cells that primarily expressed SCA-1, NANOG, and mesenchymal markers, CD90, CD105, and CD73, were able to form adipocytes, osteoblasts, and cardiomyocytes in vitro. Passage 3 hPFCs (2.5 × 105 cells/heart) were injected into the pericardial cavity of the DOX-injured rat hearts, significantly improving cardiac functions after 4 weeks. The tracked and engrafted red fluorescent protein-tagged hPFCs coexpressed cardiac troponin T and connexin 43 after 4 weeks in the host myocardium. This observation was also coupled with a significant reduction in cardiac fibrosis following hPFC treatment (P < 0.0001 vs. untreated). The elevated inflammatory cytokines interleukin (IL)-6, IL-10, and tumor necrosis factor-α in the DOX-treated hearts were found to be significantly reduced (P < 0.001 vs. untreated), while the regional proangiogenic vascular endothelial growth factor A (VEGFA) level was increased in the hPFC-treated group after 4 weeks (P < 0.05 vs. untreated). hPFCs possess stem cell characteristics and can improve the cardiac functions of DOX-induced HF rats after 4 weeks through pericardial administration. The improvements were attributed to a significant reduction in cardiac fibrosis, inflammation, and elevated regional proangiogenesis factor VEGFA, with evidence of cellular engraftment and differentiation in the host myocardium.
    Matched MeSH terms: Cells, Cultured
  4. Fulltext Colonic targeting insulin-loaded trimethyl chitosan nanoparticles coated pectin for oral delivery: In vitro and In vivo studies
    Seyam S, Choukaife H, Al Rahal O, Alfatama M
    Int J Biol Macromol, 2024 Nov;281(Pt 4):136549.
    PMID: 39401622 DOI: 10.1016/j.ijbiomac.2024.136549
    Colon-targeted delivery offers several benefits for oral protein delivery, such as low proteolytic enzyme activity, a natural pH environment, and extended residence time, which improve the bioavailability of the encapsulated protein. Therefore, we hypothesize that developing a novel colonic nanocarrier system, featuring modified chitosan that is soluble at physiological pH and coated with a colon-degradable polymer, will provide an effective delivery system for oral insulin. This study aims to synthesize insulin-loaded pectin-trimethyl chitosan nanoparticles (Ins-P-TMC-NPs) as an oral insulin delivery system and to evaluate its efficacy both in vitro and in vivo. N-trimethyl chitosan (TMC), synthesized via a methylation method, was used to prepare insulin-TMC nanoparticles coated with pectin via the ionic gelation method. The nanoparticles were characterized for their physicochemical properties, cumulative release profile, and surface morphology. The in vitro biological cytotoxicity and cellular uptake of the nanoparticles were evaluated against HT-29 cells. The in vivo blood glucose-lowering effect and histological toxicity were assessed in diabetic male Sprague-Dawley rats. The results showed that Ins-P-TMC-NPs were spherical, with an average size of 379.40 ± 40.26 nm, a polydispersity index of 24.10 ± 1.03 %, a zeta potential of +17.20 ± 0.52 mV, and a loading efficiency of 83.21 ± 1.23 %. Compared to uncoated TMC nanoparticles, Ins-P-TMC-NPs reduced insulin loss in simulated gastrointestinal fluid by approximately 67.23 ± 0.97 % and provided controlled insulin release in simulated colonic fluid. In vitro bioactivity studies revealed that Ins-P-TMC-NPs were non-toxic, with cell viability of 91.12 ± 0.91 % after 24 h of treatment, and exhibited high cellular uptake in the HT-29 cell line with a fluorescence intensity of 37.80 ± 2.40 after 4 h of incubation. Furthermore, the in vivo study demonstrated a sustained reduction in blood glucose levels after oral administration of Ins-P-TMC-NPs, peaking after 8 h with a blood glucose reduction of 87 ± 1.03 %. Histological sections showed no signs of toxicity when compared to those of healthy rats. Overall, the developed colon-targeted oral insulin delivery system exhibits strong potential as a candidate for effective oral insulin administration.
    Matched MeSH terms: HT29 Cells
  5. Antiviral activity of povidone-iodine gargle and mouthwash solution against Enterovirus A71, Coxsackieviruses A16, A10 and A6
    Ang WX, Tan SH, Wong KT, Perera D, Kuppusamy UR, Ong KC
    Trop Biomed, 2024 Sep 01;41(3):241-250.
    PMID: 39548776 DOI: 10.47665/tb.41.3.002
    Hand, Foot and Mouth Disease (HFMD), a highly contagious viral disease common among infants and young children, is primarily caused by Enterovirus A71 (EV-A71) and Coxsackievirus A16 (CVA16). Nonetheless, emerging enteroviruses, such as CV-A10 and CV-A6, have also caused widespread outbreaks globally, in part due to the absence of effective antiviral therapies, and the high personto-person transmission rate. Person-to-person transmission is usually through fecal-oral or oral-oral routes, and sometimes via droplets. As the oral cavity is a primary site for early virus infection and replication, controlling oral viral shedding can mitigate the risk of transmission through this route. Povidone-iodine (PVP-I), a widely used antiseptic, has shown broad-spectrum antimicrobial properties but antiviral studies against HFMD-causing enteroviruses are limited, especially for CV-A10 and CVA6. Our study demonstrated that a 1% PVP-I solution (final concentration of 0.5%) exhibited virucidal activity against EV-A71, CV-A16, CV-A10, and CV-A6. All seven EV-A71 isolates and five CV-A16 isolates showed a significant virus titer reduction after a 1-minute incubation, while five CV-A10 isolates and two CV-A6 isolates required a 5-minute incubation to achieve this. The virucidal activity was confirmed through the EN14476:2013+A2:2019 virucidal quantitative suspension test, wherein all four viruses were completely inactivated after a 30-minute incubation with PVP-I at 37°C under both clean and dirty conditions. Western blot analysis suggested that PVP-I could affect the VP1 structural proteins of EV-A71. Our results suggest that PVP-I could serve as a potential virucidal agent to reduce the risk of person-to-person transmission of HFMD.
    Matched MeSH terms: Vero Cells
  6. Fulltext Construction of an infectious cDNA clone of Enterovirus 71: insights into the factors ensuring experimental success
    Lazouskaya NV, Palombo EA, Poh CL, Barton PA
    J Virol Methods, 2014 Mar;197:67-76.
    PMID: 24361875 DOI: 10.1016/j.jviromet.2013.12.005
    Enterovirus 71 (EV 71) is a causative agent of mild Hand Foot and Mouth Disease but is capable of causing severe complications in the CNS in young children. Reverse genetics technology is currently widely used to study the pathogenesis of the virus. The aim of this work was to determine and evaluate the factors which can contribute to infectivity of EV 71 RNA transcripts in vitro. Two strategies, overlapping RT-PCR and long distance RT-PCR, were employed to obtain the full-length genome cDNA clones of the virus. The length of the poly(A) tail and the presence of non-viral 3'-terminal sequences were studied in regard to their effects on infectivity of the in vitro RNA transcripts of EV 71 in cell culture. The data revealed that only cDNA clones obtained after long distance RT-PCR were infectious. No differences were observed in virus titres after transfection with in vitro RNA harbouring a poly(A) tail of 18 or 30 adenines in length, irrespective of the non-viral sequences at the 3'-terminus.
    Matched MeSH terms: Vero Cells
  7. Infectivity titration of the fast-replicating and cytopathic hepatitis A virus strain HM175A.2 by an in situ enzyme immunoassay
    Yap KL, Lam SK
    J Virol Methods, 1994 Apr;47(1-2):217-26.
    PMID: 8051228
    A simple, rapid and objective infectivity assay based on an in situ enzyme immunoassay (EIA) was developed for the fast-growing and cytopathic cell culture-adapted hepatitis A virus (HAV) strain HM175A.2. Infectivity titration by EIA correlated well with titration by cytopathic effects. The reliability of this assay was demonstrated by close agreement in virus infectivity titers among different assays of the same virus aliquot and between assays of different virus aliquots. HAV infected cell cultures after fixation could be stored for up to 1 week before testing without decline in virus titer.
    Matched MeSH terms: Cells, Cultured
  8. Mechanisms of S-phase arrest and mitochondrial dysfunction in complex III by DHODH inhibitors in tumorigenic TNBC cells
    Shahhiran MAA, Abdul Kadir MF, Nor Rashid N, Abdul-Rahman PS, Othman S
    Histochem Cell Biol, 2024 Nov 18;163(1):3.
    PMID: 39557682 DOI: 10.1007/s00418-024-02339-0
    Dihydroorotate dehydrogenase (DHODH) inhibitors have recently gained increasing research interest owing to their potential for treating breast cancers. We explored their effects in different breast cancer subtypes, focusing on mitochondrial dysfunction. The sensitivity of different subtypes to the inhibitors was investigated with respect to DHODH expression, tumorigenic, and receptor status. Analysis of respiratory complexes, cell cycle, reactive oxygen species (ROS), and cell differentiation were performed. Four cell lines with different receptor status were included, namely MCF-7, MDAMB-231, SKBR-3, and MCF-10A. We showed that MCF-7 and MDAMB-231 cells of the subtypes (ER+/PR+/HER2-) and (ER-/PR-/HER2-), respectively, were responsive to brequinar. Brequinar (BQR) caused cell cycle arrest in the S-phase in sensitive subtypes of breast cells but induced cell differentiation only in poorly differentiated breast cells. All cell subtypes showed increased generation of ROS, both intracellular and mitochondrial ROS with a greater increase seen in mitochondrial ROS in response to DHODH inhibitor, subsequently contributing to mitochondrial dysfunction. BQR also disrupts the function of complex III in ER+/PR+ and triple negative breast cancer (TNBC) subtypes. Collectively, we have found that MDAMB-231 TNBC cell was the most affected by DHODH inhibition in terms of sensitivity, cell cycle arrest, induction of cell differentiation, production of ROS, and mitochondrial complexes disruption. In conclusion, these findings suggest that DHODH inhibitors can potentially become a valuable targeted therapy for TNBC subtype and further consolidates its therapeutic potential as part of the combinatorial therapy against this resilient breast cancer subtype.
    Matched MeSH terms: Tumor Cells, Cultured
  9. Fulltext Centella asiatica (L.) Urban. Attenuates Cell Damage in Hydrogen Peroxide-Induced Oxidative Stress in Transgenic Murine Embryonic Stem Cell Line-Derived Neural-Like Cells: A Preliminary Study for Potential Treatment of Alzheimer's Disease
    Mansor NI, Ling KH, Rosli R, Hassan Z, Adenan MI, Nordin N
    J Alzheimers Dis, 2023;94(s1):S21-S44.
    PMID: 37334592 DOI: 10.3233/JAD-221233
    BACKGROUND: Centella asiatica (L.) (C. asiatica) is commonly known in South East and South East Asia communities for its nutritional and medicinal benefits. Besides being traditionally used to enhance memory and accelerate wound healing, its phytochemicals have been extensively documented for their neuroprotective, neuroregenerative, and antioxidant properties.

    OBJECTIVE: The present study aims to investigate the effects of a standardized raw extract of C. asiatica (RECA) on hydrogen peroxide (H2O2)-induced oxidative stress and apoptotic death in neural-like cells derived from mouse embryonic stem (ES) cell line.

    METHODS: A transgenic mouse ES cell (46C) was differentiated into neural-like cells using 4-/4+ protocol with addition of all-trans retinoic acid. These cells were then exposed to H2O2 for 24 h. The effects of RECA on H2O2-induced neural-like cells were assessed through cell viability, apoptosis, and reactive oxygen species (ROS) assays, as well as neurite length measurement. The gene expression levels of neuronal-specific and antioxidant markers were assessed by RT-qPCR analysis.

    RESULTS: Pre-treatment with H2O2 for 24 hours, in a dose-dependent manner, damaged neural-like cells as marked by a decrease in cell viability, substantial increase in intracellular ROS accumulation, and increase in apoptotic rate compared to untreated cells. These cells were used to treat with RECA. Treatment with RECA for 48 h remarkably restored cell survival and promoted neurite outgrowth in the H2O2- damaged neurons by increasing cell viability and decreasing ROS activity. RT-qPCR analysis revealed that RECA upregulated the level of antioxidant genes such as thioredoxin-1 (Trx-1) and heme oxygenase-1 (HO-1) of treated cells, as well as the expression level of neuronal-specific markers such as Tuj1 and MAP2 genes, suggesting their contribution in neuritogenic effect.

    CONCLUSION: Our findings indicate that RECA promotes neuroregenerative effects and exhibits antioxidant properties, suggesting a valuable synergistic activity of its phytochemical constituents, thus, making the extract a promising candidate in preventing or treating oxidative stress-associated Alzheimer's disease.

    Matched MeSH terms: Embryonic Stem Cells
  10. Biopolymer collagen-chitosan scaffold containing Aloe vera for chondrogenic efficacy on cartilage tissue engineering
    Jithendra P, Mohamed JMM, Annamalai D, Al-Serwi RH, Ibrahim AM, El-Sherbiny M, et al.
    Int J Biol Macromol, 2023 Sep 01;248:125948.
    PMID: 37482169 DOI: 10.1016/j.ijbiomac.2023.125948
    The chondrogenic efficacy of aloe vera blended collagen-chitosan (COL-CS-AV) porous scaffold was investigated using articular chondrocytes in a standard condition. Cytocompatibility was analyzed using fluorescent dyes (calcein AM/ethidium bromide) and the viable cells were quantified by MTT assay. Glycosaminoglycan (GAG) content of ECM was estimated by using 1, 9-Dimethyl methylene Blue (DMMB). The total RNA content was quantified and the cartilage specific genes (col2a1, Acan) were amplified by reverse transcription-PCR from the cell lysate of the scaffolds. Histological examination was made using Haematoxylin and Eosin (H&E), safranin-O, masson's trichrome, alcian blue, and alizarin red to stain the specific component of ECM secreted on the construct. The cartilage specific collagen type II was estimated by immunohistochemistry using monoclonal type II collagen antibody. The results of these studies proved that COL-CS-AV scaffold has more chondrogenic efficacy than COL-CS, thus the aloe vera blend COL-CS-AV scaffold might be used as suitable candidate for cartilage tissue engineering.
    Matched MeSH terms: Cells, Cultured
  11. A reappraisal of the role of Zn2+ in TGF-beta1-induced apoptosis in primary hepatocytes
    Inayat-Hussain SH, Cohen GM, Cain K
    Cell Biol Toxicol, 1999;15(6):381-7.
    PMID: 10811533
    There is now a wealth of information regarding the apoptotic mode of cell death and its importance in toxicological studies in many mammalian organs including the liver. In this study, we investigated the modulatory effects of the heavy metal Zn2+ on transforming growth factor-beta1 (TGF-beta1)-induced apoptosis in primary rat hepatocytes. Apoptosis induced by TGF-beta1 (1 ng/ml) in hepatocytes was accompanied by nuclear condensation as assessed morphologically by staining with Hoechst 33258 and DNA cleavage as detected biochemically by in situ end-labeling, field inversion and conventional gel electrophoresis. Pretreatment with 100 micromol/L Zn2+ abrogated the nuclear condensation, in situ end-labeling, and DNA laddering in TGF-beta1-treated hepatocytes. Surprisingly, Zn2+ did not inhibit the formation of high-molecular-weight DNA fragments (30-50 kbp to 250-300 kbp). These data provide evidence that Zn2+ exerts its effects on the endonucleases that act downstream in the execution phase of TGF-beta1-induced apoptosis in hepatocytes.
    Matched MeSH terms: Cells, Cultured
  12. Fulltext Effectiveness of imatinib mesylate over etoposide in the treatment of sensitive and resistant chronic myeloid leukaemia cells in vitro
    Husaini R, Ahmad M, Zakaria Z
    Exp Ther Med, 2017 Jun;13(6):3209-3216.
    PMID: 28587395 DOI: 10.3892/etm.2017.4443
    Chronic myeloid leukaemia (CML) is a form of leukaemia derived from the myeloid cell lineage. Imatinib mesylate, the breakpoint cluster region-abelson murine leukeamia kinase inhibitor, is a specific reagent used in the clinical treatment of CML. The DNA topoisomerase II inhibitor, etoposide, is also employed as a therapeutic, though it is used to a lesser extent. The present study aims to evaluate the effects of CML-targeted therapy, utilising imatinib mesylate and etoposide in the in vitro treatment of parental sensitive and adriamycin-resistant CML in the K562 and K562/ADM cell lines, respectively. Preliminary work involved the screening of multidrug resistant (MDR) gene expression, including MDR1, MRP1 and B-cell lymphoma 2 (BCL-2) at the mRNA levels. The sensitive and resistant CML cell lines expressed the MRP1 gene, though the sensitive K562 cells expressed low, almost undetectable levels of MDR1 and BCL-2 genes relative to the K562/ADM cells. Following treatment with imatinib mesylate or etoposide, the IC50 for imatinib mesylate did not differ between the sensitive and resistant cell lines (0.492±0.024 and 0.378±0.029, respectively), indicating that imatinib mesylate is effective in the treatment of CML regardless of cell chemosensitivity. However, the IC50 for etoposide in sensitive K562 cells was markedly lower than that of K562/ADM cells (50.6±16.5 and 194±8.46 µM, respectively), suggesting that the higher expression levels of MDR1 and/or BCL-2 mRNA in resistant cells may be partially responsible for this effect. This is supported by terminal deoxynucleotidyl transferase dUTP nick-end labeling data, whereby a higher percentage of apoptotic cells were found in the sensitive and resistant K562 cells treated with imatinib mesylate (29.3±0.2 and 31.9±16.7%, respectively), whereas etoposide caused significant apoptosis of sensitive K562 cells (18.3±8.35%) relative to K562/ADM cells (5.17±3.3%). In addition, the MDR genes in K562/ADM cells were knocked down by short interfering RNAs. The percentage knockdowns were 15.4% for MRP1, 17.8% for MDR and 30.7% for BCL-2, which resulted in a non-significant difference in the half maximal inhibitory concentration value of K562/ADM cells relative to K562 cells upon treatment with etoposide.
    Matched MeSH terms: K562 Cells
  13. Fulltext Melatonin promotes Schwann cell dedifferentiation and proliferation through the Ras/Raf/ERK and MAPK pathways, and glial cell-derived neurotrophic factor expression
    Tiong YL, Ng KY, Koh RY, Ponnudurai G, Chye SM
    Exp Ther Med, 2020 Nov;20(5):16.
    PMID: 32934681 DOI: 10.3892/etm.2020.9143
    Upon peripheral nerve injury (PNI), continuous proliferation of Schwann cells is critical for axon regeneration and tubular reconstruction for nerve regeneration. Melatonin is a hormone that is able to induce proliferation in various cell types. In the present study, the effects of melatonin on promoting Schwann cell proliferation and the molecular mechanism involved were investigated. The present results showed that melatonin enhanced the melatonin receptors (MT1 and MT2) expression in Schwann cells. Melatonin induced Schwann cell dedifferentiation into progenitor-like Schwann cells, as observed by immunofluorescence staining, which showed Sox2 marker expression. In addition, melatonin enhanced Schwann cell proliferation, mediated by the upregulation of glial cell-derived neurotropic factor (GNDF) and protein kinase C (PKC). Furthermore, the Ras/Raf/ERK and MAPK signaling pathways were also involved in Schwann cell dedifferentiation and proliferation. In conclusion, melatonin induced Schwann cell dedifferentiation and proliferation via the Ras/Raf/ERK, MAPK and GDNF/PKC pathways. The present results suggested that melatonin could be used to enhance the recovery of PNI.
    Matched MeSH terms: Schwann Cells
  14. IFN-γ and IL-18 in conditioned media of parasite-infected host and IL-21-silenced colorectal cancer cells
    Ge P, Ong CY, Abdalkareem AE, Khoo BY, Yuan B
    Exp Ther Med, 2021 Feb;21(2):103.
    PMID: 33335566 DOI: 10.3892/etm.2020.9535
    The presence of certain soluble factors may provide a possible selective advantage for a parasite to gradually modify cell proliferation in neighbouring cells, which may result in chronic diseases. These soluble factors present in the conditioned medium also allow the parasite to invade rapidly into more host cells. The present study aimed to determine the levels of a group of type 1 T helper (Th1) cytokines in the conditioned media of host cells infected with parasites and in IL-21-silenced colorectal cancer cells. The conditioned media of human foreskin fibroblasts (HFFs) parasitized with the RH and ME49 strains of Toxoplasma gondii for 10 days were prepared, and subsequently the levels of the Th1 cytokines in the conditioned media were determined by ELISA. HFFs were incubated with the growth media containing selected soluble factors, and cell proliferation markers were subsequently analysed by reverse transcription-quantitative PCR. The mRNA expression level of cell proliferation markers was also examined in IL-21-silenced HCT116 cells, where the levels of soluble factors in the conditioned media were also determined as aforementioned. The results of the present study demonstrated that HFFs parasitized with ME49 released elevated levels of IFN-γ and lower levels of IL-18 into the conditioned medium compared with the controls. These phenomena were not observed in the conditioned medium of HFFs parasitized with RH. Similar levels of these soluble factors were also detected in the conditioned medium of IL-21-silenced HCT116 cells. The results of the present study also revealed that Ki67 and proliferating cell nuclear antigen mRNA expression was altered in host cells incubated with various levels of IFN-γ and IL-18, as well as in IL-21-silenced HCT116 cells compared with the respective controls. In conclusion, the current study provided preliminary evidence on the fundamental molecular mechanisms of host-parasite interactions that result in chronic diseases, which may aid in the treatment of these diseases in the relevant endemic regions.
    Matched MeSH terms: HCT116 Cells
  15. Mechanisms of the In Vivo Antitumor Activity of Polyalthia longifolia Leaf Extract Against HeLa Cell Xenograft Tumor: A Microscopic-Based Histological and Immunohistochemical Microanalyses
    Cilwyn-Shalitha B, Sasidharan S
    Microsc Microanal, 2023 Jun 09;29(3):1153-1167.
    PMID: 37749670 DOI: 10.1093/micmic/ozad023
    The present study investigated the effects of Polyalthia longifolia leaf extract against the growth of HeLa cell xenograft tumor in nude mice and its underlying mechanism. The nude mice xenografted with HeLa cells were treated with 5% DMSO (vehicle control), 20 mg/kg/body weight of etoposide (positive control), and 500 and 1000 mg/kg/body weight of leaf extract, respectively. Antitumor activity was evaluated with apoptosis, proliferation, and angiogenesis using microscopic-based histological and immunohistochemical microanalyses. The tumor tissue histological and immunohistochemical analyses showed that the HeLa tumor cell death was associated with apoptosis and decreased (p < 0.05) expression of Ki-67 in tumor tissues. The extract also inhibits tumor angiogenesis by downregulating (p < 0.05) the expression of VEGF and CD31 in tumor tissues after treatment for 35 days. Conclusively, the P. longifolia leaf extract effectively inhibited HeLa cell xenograft growth in nude mice. The possible mechanism was related to induction of apoptosis, inhibition of tumor HeLa cell proliferation by decreasing the Ki-67 protein expression, and prevention of tumor angiogenesis by reducing VEGF and CD31 protein expression in HeLa cells.
    Matched MeSH terms: HeLa Cells
  16. Effect of supplementation of dermal fibroblasts conditioned medium on expansion of keratinocytes through enhancing attachment
    Chowdhury SR, Aminuddin BS, Ruszymah BH
    Indian J Exp Biol, 2012 May;50(5):332-9.
    PMID: 22803323
    In the present study in vitro expansion of human keratinocytes by supplementing dermal fibroblasts conditioned medium (DFCM) has been reported. Effect of two different DFCM acquired by culturing fibroblasts in keratinocyte-specific medium (defined keratinocytes serum free medium, DFCM-DKSFM) and fibroblast-specific serum free medium (F12: DMEM nutrient mix, DFCM-FD) have been compared. Growth kinetics of keratinocytes in terms of efficiency of cell attachment, expansion index, apparent specific growth rate and growth potential at the end of culture was evaluated in culture supplemented with DFCM-DKSFM and DFCM-FD in comparison with control i.e. DKSFM only. Results indicated that supplementation of DFCM caused significant increase in keratinocyte attachment. Efficiency of keratinocyte attachment in culture supplemented with bFCM-DKSFM was significantly higher compared to those cultured in DFCM-FD and DKSFM. In addition, the expansion index of keratinocytes in cultures supplemented with DFCM-DKSFM and DFCM-FD were 3.7 and 2.2 times higher than that of control condition even though the apparent growth rate and proliferative potential was found significantly lower. These results suggested that supplementation of DFCM enhanced expansion of keratinocyte by increasing efficiency of cell attachment, and DFCM-DKSFM provided suitable condition for in vitro expansion of keratinocytes compared to DFCM-FD and control condition.
    Matched MeSH terms: Cells, Cultured
  17. Protective effect of myricetin derivatives from Syzygium malaccense against hydrogen peroxide-induced stress in ARPE-19 cells
    Arumugam B, Palanisamy UD, Chua KH, Kuppusamy UR
    Mol Vis, 2019;25:47-59.
    PMID: 30820141
    Purpose: Oxidative stress is implicated in the etiology of diabetes and its debilitating complications, such as diabetic retinopathy (DR). Various flavonoids have been reported to be useful in reducing DR progression. Myricetin derivatives (F2) isolated from leaf extract of Syzygium malaccense have the potential to serve as functional food as reported previously. The present study was performed with the aim of determining the antioxidant potential and protective effect of myricetin derivatives (F2) isolated from leaf extract of S. malaccense against glucose oxidase (GO)-induced hydrogen peroxide (H2O2) production that causes oxidative stress in ARPE-19 (RPE) cells.

    Methods: Antioxidant properties were assessed through various radical (DPPH, ABTS, and nitric oxide) scavenging assays and determination of total phenolic content and ferric reducing antioxidant power level. ARPE-19 cells were preincubated with samples before the addition of GO (to generate H2O2). Cell viability, change in intracellular reactive oxygen species (ROS), H2O2 levels in cell culture supernatant, and gene expression were assessed.

    Results: F2 showed higher antioxidant levels than the extract when assessed for radical scavenging activities and ferric reducing antioxidant power. F2 protected the ARPE-19 cells against GO-H2O2-induced oxidative stress by reducing the production of H2O2 and intracellular reactive oxygen species. This was achieved by the activation of nuclear factor erythroid 2-related factor 2 (Nrf2/NFE2L2) and superoxide dismutase (SOD2), as well as downregulation of nitric oxide producer (NOS2) at the transcriptional level.

    Conclusions: The results showed that myricetin derivatives from S. malaccense have the capacity to exert considerable exogenous antioxidant activities and stimulate endogenous antioxidant activities. Therefore, these derivatives have excellent potential to be developed as therapeutic agents for managing DR.

    Matched MeSH terms: Epithelial Cells/cytology; Epithelial Cells/drug effects*; Epithelial Cells/metabolism
  18. Synthesis, characterization and crystal structure of organotin(IV) N-butyl-N-phenyldithiocarbamate compounds and their cytotoxicity in human leukemia cell lines
    Kamaludin NF, Awang N, Baba I, Hamid A, Meng CK
    Pak J Biol Sci, 2013 Jan 01;16(1):12-21.
    PMID: 24199481
    Organotin complexes are recognized as the biologically active compounds in inducing cancerous cells death at very low doses. To date, organotin compounds currently appear among the most potent candidates in research related to the new anticancer drugs. In this study, new organotin(IV) N-butyl-N-phenyldithiocarbamate compounds have been successfully synthesized between the reaction of N-butylaniline amine with organotin(IV) chloride in 1:2/1:1 molar ratio. All compounds were characterized using the elemental analysis, FT-IR and NMR spectroscopy. The single crystal structure was determined by X-ray single crystal analysis. The elemental analysis showed good agreement with the suggested formula (C4H9)2Sn[S2CN(C4H9)(C6H5)]2 (Compound 1 and 2), (C6H5)2Sn[S2CN(C4H9)(C6H5)]2 (Compound 3) and (C6H5)3Sn[S2CN(C4H9)(C6H5)] (Compound 4). The important infrared absorbance peaks, v (C = N) and v(C = S) were detected in range between 1457-1489 cm(-1) and 951-996 cm(-1), respectively. The chemical shift of carbon in NCS2 group obtained from 13C NMR was found in range 198.86-203.53 ppm. The crystal structure of compound 4 showed that the dithiocarbamate ligand coordinates in a monodentate fashion. It crystallized in monoclinic P2(1)/n space group with the crystal cell parameter: a = 10.0488(1) angstroms, b = 18.0008(2) angstroms, c = 15.2054(2) angstroms, beta = 102.442(1) degrees and R = 0.044. The cytotoxicity (IC50) of these compounds against Jurkat E6.1 and K-562 leukemia cells were in the range between 0.4-0.8 and 1.8-5.3 microM, respectively as assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazholium bromide (MTT) assay. In conclusion, our study demonstrate that all compounds showed potent cytotoxicity towards both cell lines tested with the triphenyltin(IV) compound displayed the greatest effect.
    Matched MeSH terms: Jurkat Cells
  19. Molecular docking and dynamics supported investigation of antiviral activity of Lichen metabolites of Roccella montagnei: an in silico and in vitro study
    Bhat NB, Das S, Sridevi BVS, H RC, Nayaka S, S N, et al.
    J Biomol Struct Dyn, 2023;41(21):11484-11497.
    PMID: 36803674 DOI: 10.1080/07391102.2023.2180666
    Lichens are symbiotic organisms that have been traditionally used for treating different kinds of ailments. As there are only a few reports on the antiviral activity of lichens, we thought of evaluating the anti-Herpes simplex virus-1 (HSV-1) activity of methanolic extract of Roccella montagnei and their isolated compounds. Fractionation of crude methanolic extract of Roccella montagnei by column chromatography isolated two pure compounds. Antiviral activity was assessed using a CPE inhibition assay at non-cytotoxic concentrations on Vero cells. Molecular docking and dynamics studies were carried out against Herpes simplex type-1 thymidine kinase to understand the binding interactions of the isolated compounds with reference to acyclovir. Isolated compounds were characterized as methyl orsellinate and montagnetol by spectral methods. Methanolic extract of Roccella montagnei exhibited an EC50 value of 56.51 µg/ml, while the compounds methyl orsellinate and montagnetol offered EC50 values of 13.50 µg/ml and 37.52 µg/ml, respectively, against HSV-1 viral infection on Vero cell lines. The selectively index (SI) of montagnetol (10.93) was found to be higher when compared to that of methyl orsellinate (5.55), indicating its better anti-HSV-1 activity. The docking and dynamics studies showed montagnetol was stable throughout the 100 ns, having better interactions and docking scores with HSV-1 thymidine kinase than methyl orsellinate, as well as the standard. To understand the mechanism of montagnetol's anti-HSV-1 activity, more research is required, and this could lead to the discovery of new and effective antiviral agents.Communicated by Ramaswamy H. Sarma.
    Matched MeSH terms: Vero Cells
  20. In-vitro and in-silico anti-HSV-1 activity of a marine steroid from the jellyfish Cassiopea andromeda venom
    Shamsian S, Nabipour I, Mohebbi G, Baghban N, Zare M, Zandi K, et al.
    Microb Pathog, 2024 Jan;186:106486.
    PMID: 38056601 DOI: 10.1016/j.micpath.2023.106486
    In this study, we investigated the potential in vitro anti-HSV-1 activities of the Cassiopea andromeda jellyfish tentacle extract (TE) and its fractions, as well as computational work on the thymidine kinase (TK) inhibitory activity of the identified secondary metabolites. The LD50, secondary metabolite identification, preparative and analytical chromatography, and in silico TK assessment were performed using the Spearman-Karber, GC-MS, silica gel column chromatography, RP-HPLC, LC-MS, and docking methods, respectively. The antiviral activity of TE and the two purified compounds Ca2 and Ca7 against HSV-1 in Vero cells was evaluated by MTT and RT-PCR assays. The LD50 (IV, mouse) values of TE, Ca2, and Ca7 were 104.0 ± 4, 5120 ± 14, and 197.0 ± 7 (μg/kg), respectively. They exhibited extremely effective antiviral activity against HSV-1. The CC50 and MNTD of TE, Ca2, and Ca7 were (125, 62.5), (25, 12.5), and (50, 3.125) μg/ml, respectively. GC-MS analysis of the tentacle extract revealed seven structurally distinct chemical compositions. Four of the seven compounds had a steroid structure. According to the docking results, all compounds showed binding affinity to the active sites of both thymidine kinase chains. Among them, the steroid compound Pregn-5-ene-3,11-dione, 17,20:20,21 bis [methylenebis(oxy)]-, cyclic 3-(1,2-ethane diyl acetal) (Ca2) exhibited the highest affinity for both enzyme chains, surpassing that of standard acyclovir. In silico data confirmed the experimental results. We conclude that the oxosteroid Ca2 may act as a potent agent against HSV-1.
    Matched MeSH terms: Vero Cells
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