scholarly journals Neurymenolide A, a Novel Mitotic Spindle Poison from the New Caledonian Rhodophyta Phacelocarpus neurymenioides

Marine Drugs ◽  
2019 ◽  
Vol 17 (2) ◽  
pp. 93 ◽  
Author(s):  
Sofia-Eléna Motuhi ◽  
Omid Feizbakhsh ◽  
Béatrice Foll-Josselin ◽  
Blandine Baratte ◽  
Claire Delehouzé ◽  
...  
Keyword(s):  
Total Synthesis ◽  
Cell Lines ◽  
Mitotic Spindle ◽  
Hematological Malignancies ◽  
Mitotic Catastrophe ◽  
Antibiotic Resistant ◽  
Resistant Strains ◽  
Stereogenic Center ◽  
First Time

The marine α-pyrone macrolide neurymenolide A was previously isolated from the Fijian red macroalga, Neurymenia fraxinifolia, and characterized as an antibacterial agent against antibiotic-resistant strains that also exhibited moderate cytotoxicity in vitro against cancer cell lines. This compound was also shown to exhibit allelopathic effects on Scleractinian corals. However, to date no mechanism of action has been described in the literature. The present study showed, for the first time, the isolation of neurymenolide A from the New Caledonian Rhodophyta, Phacelocarpus neurymenioides. We confirmed the compound’s moderate cytotoxicity in vitro against several human cell lines, including solid and hematological malignancies. Furthermore, we combined fluorescence microscopy and flow cytometry to demonstrate that treatment of U-2 OS osteosarcoma human cells with neurymenolide A could block cell division in prometaphase by inhibiting the correct formation of the mitotic spindle, which induced a mitotic catastrophe that led to necrosis and apoptosis. Absolute configuration of the stereogenic center C-17 of neurymenolide A was deduced by comparison of the experimental and theoretical circular dichroism spectra. Since the total synthesis of this compound has already been described, our findings open new avenues in cancer treatment for this class of marine molecules, including a new source for the natural product.

Mechanisms involved in effects of antimicrobial peptides, bactenectins ChBac3.4, ChBac5, and mini-ChBac7.5Nb, on bacterial cells

2017 ◽  
pp. 43-50
Author(s):  
О.В. Шамова ◽  
М.С. Жаркова ◽  
П.М. Копейкин ◽  
Д.С. Орлов ◽  
Е.А. Корнева
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Activity ◽  
Innate Immunity ◽  
Infectious Diseases ◽  
Metabolic Activity ◽  
Capra Hircus ◽  
Bacterial Cells ◽  
Antibiotic Resistant ◽  
Resistant Strains

Антимикробные пептиды (АМП) системы врожденного иммунитета - соединения, играющие важную роль в патогенезе инфекционных заболеваний, так как обладают свойством инактивировать широкий спектр патогенных бактерий, обеспечивая противомикробную защиту живых организмов. В настоящее время АМП рассматриваются как потенциальные соединения-корректоры инфекционной патологии, вызываемой антибиотикорезистентными бактериями (АБР). Цель данной работы состояла в изученим механизмов антибактериального действия трех пептидов, принадлежащих к семейству бактенецинов - ChBac3.4, ChBac5 и mini-ChBac7.5Nb. Эти химически синтезированные пептиды являются аналогами природных пролин-богатых АМП, обнаруженных в лейкоцитах домашней козы Capra hircus и проявляющих высокую антимикробную активность, в том числе и в отношении грамотрицательных АБР. Методы. Минимальные ингибирующие и минимальные бактерицидные концентрации пептидов (МИК и МБК) определяли методом серийных разведений в жидкой питательной среде с последующим высевом на плотную питательную среду. Эффекты пептидов на проницаемость цитоплазматической мембраны бактерий для хромогенного маркера исследовали с использованием генетически модифицированного штамма Escherichia coli ML35p. Действие бактенецинов на метаболическую активность бактерий изучали с применением маркера резазурина. Результаты. Показано, что все исследованные пептиды проявляют высокую антимикробную активность в отношении Escherichia coli ML35p и антибиотикоустойчивых штаммов Escherichia coli ESBL и Acinetobacter baumannii in vitro, но их действие на бактериальные клетки разное. Использован комплекс методик, позволяющих наблюдать в режиме реального времени динамику действия бактенецинов в различных концентрациях (включая их МИК и МБК) на барьерную функцию цитоплазматической мембраны и на интенсивность метаболизма бактериальных клеток, что дало возможность выявить различия в характере воздействия бактенецинов, отличающихся по структуре молекулы, на исследуемые микроорганизмы. Установлено, что действие каждого из трех исследованных бактенецинов в бактерицидных концентрациях отличается по эффективности нарушения целостности бактериальных мембран и в скорости подавления метаболизма клеток. Заключение. Полученная информация дополнит существующие фундаментальные представления о механизмах действия пролин-богатых пептидов врожденного иммунитета, а также послужит основой для биотехнологических исследований, направленных на разработку на базе этих соединений новых антибиотических препаратов для коррекции инфекционных заболеваний, вызываемых АБР и являющимися причинами тяжелых внутрибольничных инфекций. Antimicrobial peptides (AMPs) of the innate immunity are compounds that play an important role in pathogenesis of infectious diseases due to their ability to inactivate a broad array of pathogenic bacteria, thereby providing anti-microbial host defense. AMPs are currently considered promising compounds for treatment of infectious diseases caused by antibiotic-resistant bacteria. The aim of this study was to investigate molecular mechanisms of the antibacterial action of three peptides from the bactenecin family, ChBac3.4, ChBac5, and mini-ChBac7.5Nb. These chemically synthesized peptides are analogues of natural proline-rich AMPs previously discovered by the authors of the present study in leukocytes of the domestic goat, Capra hircus. These peptides exhibit a high antimicrobial activity, in particular, against antibiotic-resistant gram-negative bacteria. Methods. Minimum inhibitory and minimum bactericidal concentrations of the peptides (MIC and MBC) were determined using the broth microdilution assay followed by subculturing on agar plates. Effects of the AMPs on bacterial cytoplasmic membrane permeability for a chromogenic marker were explored using a genetically modified strain, Escherichia coli ML35p. The effect of bactenecins on bacterial metabolic activity was studied using a resazurin marker. Results. All the studied peptides showed a high in vitro antimicrobial activity against Escherichia coli ML35p and antibiotic-resistant strains, Escherichia coli ESBL and Acinetobacter baumannii, but differed in features of their action on bacterial cells. The used combination of techniques allowed the real-time monitoring of effects of bactenecin at different concentrations (including their MIC and MBC) on the cell membrane barrier function and metabolic activity of bacteria. The differences in effects of these three structurally different bactenecins on the studied microorganisms implied that these peptides at bactericidal concentrations differed in their capability for disintegrating bacterial cell membranes and rate of inhibiting bacterial metabolism. Conclusion. The obtained information will supplement the existing basic concepts on mechanisms involved in effects of proline-rich peptides of the innate immunity. This information will also stimulate biotechnological research aimed at development of new antibiotics for treatment of infectious diseases, such as severe in-hospital infections, caused by antibiotic-resistant strains.

The Cellular Substrate: A Very Important Requirement for Baculovirus in vitro Replication

1984 ◽  
Vol 39 (9-10) ◽  
pp. 993-1002 ◽  
Author(s):  
Herbert G. Miltenburger ◽  
Werner L. Naser ◽  
Jeanne P. Harvey ◽  
Jürg Huber ◽  
Alois M. Huger
Keyword(s):  
Cell Line ◽  
Cell Lines ◽  
Cydia Pomonella ◽  
Codling Moth ◽  
Primary Cell ◽  
Insect Species ◽  
In Vitro Replication ◽  
Primary Cell Lines ◽  
First Time

Abstract We established more than 200 primary cell lines of Cydia pomonella (codling moth). 81 of them were selected and screened for replication of two baculoviruses (from two different subgroups): the Choristoneura murinana NPV and the Cydia pomonella GV. Although all these cell lines had been derived from the same insect species, they varied largely in their response to challenge with the NPV. Most of them showed CPE or produced different amounts of poly-hedra. Interestingly, we also found a few cell lines that were permissive for GV replication. To our knowledge this is the first time that GV replication in cell lines has been obtained. Our results show that cell line properties are most important for baculovirus in vitro replication.

scholarly journals Novel Thienopyrimidine Derivative, RP-010, Induces β-Catenin Fragmentation and Is Efficacious against Prostate Cancer Cells

Cancers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 711 ◽  
Author(s):  
Haneen Amawi ◽  
Noor Hussein ◽  
Sai H. S. Boddu ◽  
Chandrabose Karthikeyan ◽  
Frederick E. Williams ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cancer Cells ◽  
Cell Lines ◽  
Nuclear Translocation ◽  
Wide Spectrum ◽  
Thiophene Ring ◽  
Mitotic Catastrophe ◽  
Prostate Cancer Cells

Thienopyrimidines containing a thiophene ring fused to pyrimidine are reported to have a wide-spectrum of anticancer efficacy in vitro. Here, we report for the first time that thieno[3,2-d]pyrimidine-based compounds, also known as the RP series, have efficacy in prostate cancer cells. The compound RP-010 was efficacious against both PC-3 and DU145 prostate cancer (PC) cells (IC50 < 1 µM). The cytotoxicity of RP-010 was significantly lower in non-PC, CHO, and CRL-1459 cell lines. RP-010 (0.5, 1, 2, and 4 µM) arrested prostate cancer cells in G2 phase of the cell cycle, and induced mitotic catastrophe and apoptosis in both PC cell lines. Mechanistic studies suggested that RP-010 (1 and 2 µM) affected the wingless-type MMTV (Wnt)/β-catenin signaling pathway, in association with β-catenin fragmentation, while also downregulating important proteins in the pathway, including LRP-6, DVL3, and c-Myc. Interestingly, RP-010 (1 and 2 µM) induced nuclear translocation of the negative feedback proteins, Naked 1 and Naked 2, in the Wnt pathway. In addition, RP-010 (0.5, 1, 2 and 4 µM) significantly decreased the migration of PC cells in vitro. Finally, RP-010 did not produce significant toxic effects in zebrafish at concentrations of up to 6 µM. In conclusion, RP-010 may be an efficacious and relatively nontoxic anticancer compound for prostate cancer. Future mechanistic and in vivo efficacy studies are needed to optimize the hit compound RP-010 for lead optimization and clinical use.

scholarly journals In vitro Antimicrobial Activity of Acne Drugs Against Skin-Associated Bacteria

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mark A. T. Blaskovich ◽  
Alysha G. Elliott ◽  
Angela M. Kavanagh ◽  
Soumya Ramu ◽  
Matthew A. Cooper
Keyword(s):  
Antimicrobial Activity ◽  
Resistant Bacteria ◽  
Microbial Infection ◽  
Antibiotic Resistant ◽  
Drug Resistant Bacteria ◽  
Cutibacterium Acnes ◽  
Common Skin ◽  
Sebum Production ◽  
Resistant Strains

Abstract Acne is a common skin affliction that involves excess sebum production and modified lipid composition, duct blockage, colonization by bacteria, and inflammation. Acne drugs target one or more of these steps, with antibiotics commonly used to treat the microbial infection for moderate to severe cases. Whilst a number of other acne therapies are purported to possess antimicrobial activity, this has been poorly documented in many cases. We conducted a comparative analysis of the activity of common topical acne drugs against the principal etiological agent associated with acne: the aerotolerant anaerobic Gram-positive organism Propionibacterium acnes (recently renamed as Cutibacterium acnes). We also assessed their impact on other bacteria that could also be affected by topical treatments, including both antibiotic-sensitive and antibiotic-resistant strains, using broth microdilution assay conditions. Drugs designated specifically as antibiotics had the greatest potency, but lost activity against resistant strains. The non-antibiotic acne agents did possess widespread antimicrobial activity, including against resistant strains, but at substantially higher concentrations. Hence, the antimicrobial activity of non-antibiotic acne agents may provide protection against a background of increased drug-resistant bacteria.

scholarly journals Comparative fitness analysis of D-cycloserine resistant mutants reveals both fitness-neutral and high-fitness cost genotypes

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Dimitrios Evangelopoulos ◽  
Gareth A. Prosser ◽  
Angela Rodgers ◽  
Belinda M. Dagg ◽  
Bhagwati Khatri ◽  
...  
Keyword(s):  
Biological Factor ◽  
Resistance Mutations ◽  
Compensatory Mechanisms ◽  
Medical Problems ◽  
Antibiotic Resistant ◽  
Clinical Resistance ◽  
Resistant Strains ◽  
Rate Of Emergence ◽  
Fitness Analysis

Abstract Drug resistant infections represent one of the most challenging medical problems of our time. D-cycloserine is an antibiotic used for six decades without significant appearance and dissemination of antibiotic resistant strains, making it an ideal model compound to understand what drives resistance evasion. We therefore investigated why Mycobacterium tuberculosis fails to become resistant to D-cycloserine. To address this question, we employed a combination of bacterial genetics, genomics, biochemistry and fitness analysis in vitro, in macrophages and in mice. Altogether, our results suggest that the ultra-low rate of emergence of D-cycloserine resistance mutations is the dominant biological factor delaying the appearance of clinical resistance to this antibiotic. Furthermore, we also identified potential compensatory mechanisms able to minimize the severe fitness costs of primary D-cycloserine resistance conferring mutations.

Combination of WEE1 and AURKA inhibition in HPV negative head and neck squamous cell carcinoma.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e14105-e14105
Author(s):  
Janaki Parameswaran ◽  
Jong Woo Lee ◽  
Teresa Sandoval-Schaefer ◽  
Jaseok P. Koo ◽  
Barbara Burtness
Keyword(s):  
Cell Death ◽  
Confocal Microscopy ◽  
Tumor Growth ◽  
Cell Lines ◽  
Aurora Kinase ◽  
Mitotic Catastrophe ◽  
Intrinsic Resistance ◽  
Mitotic Entry ◽  
Hnscc Cell

e14105 Background: Aurora Kinase A (AURKA) is overexpressed in HNSCC, and correlates with poor prognosis. It has been identified as a potential therapeutic target, yet the response rate for the AURKA inhibitor MLN8237 is only 9% in treatment refractory HNSCC. We hypothesized that although AURKA inhibitors lead to defective spindle assembly, they may also reduce mitotic entry, undermining cytotoxic effect. We predicted that adding a WEE1 inhibitor to an AURKA inhibitor would mitigate this effect and enhance cell death Methods: Cell viability assays were performed on FaDu ( p53 mut.), Detroit562 ( p53 mut.), and UNC7 ( p53 WT) HPV negative HNSCC cell lines treated with AZD1775 (AZD), MLN8237 (MLN), and combination of AZD+MLN. Oncosphere formation assays were used to confirm findings of cell death, and western blot analysis and confocal microscopy were used to investigate mechanism of synergy. The above drugs were also given at varying doses via oral gavage to FaDu xenografted nude mice. Results: There was clear synergy of AZD and MLN in-vitro. Combination Indices were determined by the Chou-Talalay method: FaDu 0.4, Detroit562 0.5, and UNC7 0.6 (synergy = < 0.8). Oncopshere assays showed inability of AZD+MLN treated cells to re-differentiate. FaDu cells treated with MLN had increased p-CDK1 and reduced phospho-histone H3 (pHH3), suggesting reduced mitotic entry. AZD+MLN treated cells had reduced p-CDK1 and increased pHH3, similar to AZD treated cells; they also had spindle disarray with poor chromatin organization on confocal microscopy indicating mitotic catastrophe. In mice, the combination of AZD+MLN inhibited tumor growth, with no apparent toxicity. Mice treated with either drug alone had tumor volumes over 1000mm3 and were sacrificed at day 21; those treated with AZD 90mg/kg and MLN 30mg/kg had tumors volumes around 300mm3 on day 28. Conclusions: AZD and MLN synergistically enhance cell death in HNSCC cell lines and significantly inhibit tumor growth in mouse xenograft models. The ability of AZD to overcome intrinsic resistance to MLN may underlie mechanism of synergy. We recommend further investigation of AURKA and WEE1 inhibition in other cancers with high AURKA expression, and in patients with HNSCC.

scholarly journals Chemical characterization and bioactive properties of Geranium molle L.: from the plant to the most active extract and its phytochemicals

2016 ◽  
Vol 7 (5) ◽  
pp. 2204-2212 ◽  
Author(s):  
V. C. Graça ◽  
Lillian Barros ◽  
Ricardo C. Calhelha ◽  
Maria Inês Dias ◽  
Ana Maria Carvalho ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Cell Lines ◽  
Human Cancer ◽  
Chemical Characterization ◽  
Human Cancer Cell ◽  
Human Cancer Cell Lines ◽  
Bioactive Properties ◽  
First Time ◽  
Geranium Molle

The phytochemical characterization, antioxidant activity and in vitro cytotoxicity against human cancer cell lines of Geranium molle L. extracts are reported for the first time.

scholarly journals Deficient biosynthesis of N-acetylglucosaminyl-phosphatidylinositol, the first intermediate of glycosyl phosphatidylinositol anchor biosynthesis, in cell lines established from patients with paroxysmal nocturnal hemoglobinuria.

1993 ◽  
Vol 177 (2) ◽  
pp. 517-521 ◽  
Author(s):  
M Takahashi ◽  
J Takeda ◽  
S Hirose ◽  
R Hyman ◽  
N Inoue ◽  
...  
Keyword(s):  
Cell Lines ◽  
Paroxysmal Nocturnal Hemoglobinuria ◽  
Japanese Patients ◽  
Gpi Anchor ◽  
Cell Hybridization ◽  
Glycosyl Phosphatidylinositol ◽  
Class A ◽  
First Time ◽  
Lines Of Evidence

Paroxysmal nocturnal hemoglobinuria (PNH) is a hemolytic disorder caused by a deficiency of biosynthesis of the glycosyl phosphatidylinositol (GPI) anchor, but the biochemical defect is not completely understood. In the present study, we have analyzed affected cell lines established recently from two Japanese patients with PNH. Two lines of evidence indicate that these cells do not synthesize N-acetylglucosaminyl-phosphatidylinositol, the first intermediate in the GPI anchor biosynthesis. First, somatic cell hybridization analysis using Thy-1-deficient murine thymoma cell lines with known biochemical defects as fusion partners showed that the PNH cell lines belong to complementation class A, which is known not to synthesize N-acetylglucosaminyl-phosphatidylinositol. Second, analysis of in vitro glycolipid biosynthesis demonstrated that cell lysates of these PNH cell lines in fact did not support biosynthesis of N-acetylglucosaminyl-phosphatidylinositol. Thus, we have characterized for the first time the exact biochemical defect leading to PNH.

scholarly journals In Vitro Activity of 3 Commercial Bacteriophage Cocktails Against Salmonella and Shigella spp. Isolates of Human Origin

2018 ◽  
Vol 3 (1) ◽  
pp. 72 ◽  
Author(s):  
Odette J. Bernasconi ◽  
Valentina Donà ◽  
Regula Tinguely ◽  
Andrea Endimiani
Keyword(s):  
Multidrug Resistant ◽  
In Vivo Studies ◽  
Salmonella Spp ◽  
Salmonella Infections ◽  
Shigella Spp ◽  
Resistant Strains ◽  
Emergence Of Resistance ◽  
First Time

Background: Salmonella and Shigella spp. are 2 of the most frequent and deadly enteric bacterial pathogens recorded worldwide. In developing countries Salmonella infections are responsible for many deaths annually and these mortality rates are prone to increase due to the emergence of resistance to antibiotics. In this overall scenario new alternative therapeutic approaches are needed.Methods: For the first time, we investigated the activity of 3 commercial bacteriophage cocktails (INTESTI, Septaphage, PYO) against a collection of contemporary Salmonella spp. (n = 30) and Shigella spp. (n = 20) strains isolated in Switzerland. Phage susceptibility was determined by implementing the spot test.Results: The overall susceptibility of Salmonella spp. to INTESTI and Septaphage was 87% and 77%, respectively. With regard to Shigella spp., the overall susceptibility to INTESTI and Septaphage was 95% and 55%, respectively. PYOwas observed to be active against only 10% of Salmonella spp. but against 95% of Shigella spp.Conclusions: Our results seem promising, especially for the INTESTI biopreparation against Salmonella enterica infections. Nevertheless, such speculation should be supported by further in vivo studies to confirm efficacy and safety of the cocktails. We also emphasize the importance of large in vitro screening analyses aimed to assess the activity of such biopreparations against contemporary multidrug-resistant strains that are emerging worldwide.Keywords: commercial; bacteriophages; Salmonella; Shigella cocktails

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