scholarly journals The Ovistatic Effect of Saprotrophic Soil Fungi on Ascaris suum Eggs

2019 ◽  
Vol 67 (3) ◽  
pp. 109-118
Author(s):  
Lidia Kołodziejczyk ◽  
Kinga Mazurkiewicz-Zapałowicz ◽  
Magdalena Twarużek ◽  
Jan Grajewski ◽  
Łukasz Łopusiewicz ◽  
...  
Keyword(s):  
Mtt Assay ◽  
Soil Fungi ◽  
Developmental Stages ◽  
Ascaris Suum ◽  
Hydrolytic Activity ◽  
Inhibitory Effect ◽  
Penicillium Expansum ◽  
Fungal Enzymes ◽  
Low Cytotoxicity ◽  
High Cytotoxicity

The aim of the study was to evaluate the potential use of selected species of soil fungi (Fusarium oxysporum, F. sulphureum, F. verticillioides, and Penicillium expansum) for the bioregulation of the dispersive stages of a parasitic nematode – the large roundworm of pig (Ascaris suum). Experimental cultures containing A. suum eggs with soil fungi and control cultures without fungi were incubated at 26°C for 28 days. Microscopic observations of the developmental stages of the A. suum eggs (zygote, 2-8 blastomeres, morula/blastula, gastrula, and larva) were performed at 7, 14, 21, and 28 days. The API-ZYM test was used to semi-quantitatively determine the activity of 19 hydrolytic fungal enzymes. The cytotoxicity of the fungi was determined with a tetrazole salt MTT assay. Microscopic observations of A. suum eggs incubated in the presence of fungi up to day 28 did not show any signs of destruction to egg shells and/or penetration of the fungi into the eggs. The ovistatic effect of all tested fungi (F. sulphureum, P. expansum, F. verticillioides, and F. oxysporum; p<0.05) was seen only on the 7th day of incubation, whereas on the 14th day, only F. verticillioides and F. oxysporum showed an inhibitory effect on the embryogenesis of A. suum, and by the 28th day, only P. expansum. The API-ZYM test showed differences in the hydrolytic activity of the tested strains, while the MTT assay showed the high cytotoxicity of F. sulphureum, the moderate cytotoxicity of F. verticillioides and P. expansum, and the low cytotoxicity of F. oxysporum. Among the fungal strains studied, F. sulphureum showed the highest ovistatic effect, which may be related to its enzymatic activity and cytotoxicity.

Inhibitory Effect of New Semisynthetic Usnic Acid Derivatives on Human Tyrosyl-DNA Phosphodiesterase 1

Planta Medica ◽  
2018 ◽  
Vol 85 (02) ◽  
pp. 103-111 ◽  
Author(s):  
Nadezhda Dyrkheeva ◽  
Olga Luzina ◽  
Aleksandr Filimonov ◽  
Olga Zakharova ◽  
Ekaterina Ilina ◽  
...  
Keyword(s):  
Biological Activity ◽  
Usnic Acid ◽  
Inhibitory Effect ◽  
Repair Enzyme ◽  
Topoisomerase 1 ◽  
Anticancer Properties ◽  
Human Dna ◽  
Whole Number ◽  
Ic50 Values ◽  
Low Cytotoxicity

AbstractUsnic acid, a lichen secondary metabolite produced by a whole number of lichens, has attracted the interest of researchers owing to its broad range of biological activity, including antiviral, antibiotic, anticancer properties, and it possessing a certain toxicity. The synthesis of new usnic acid derivatives and the investigation of their biological activity may lead to the discovery of compounds with better pharmacological and toxicity profiles. In this context, a series of new usnic acid derivatives comprising a terpenoid moiety were synthesized, and their ability to inhibit the catalytic activity of the human DNA repair enzyme tyrosyl-DNA phosphodiesterase 1 was investigated. The most potent compounds (15a, 15b, 15g, and 16a, 16b, 16g) had IC50 values in the range of 0.33 – 2.7 µM. The inhibitory properties were mainly dependent on the flexibility and length of the terpenoid moiety, but not strongly dependent on the configuration of the asymmetric centers. The synthesized derivatives showed low cytotoxicity against human cell lines in an MTT assay. They could be used as a basis for the development of more effective anticancer therapies when combined with topoisomerase 1 inhibitors.

scholarly journals Shenqi Fuzheng Injection (SFI) Enhances IFN-α Inhibitory Effect on Hepatocellular Carcinoma Cells by Reducing VEGF Expression: Validation by Gene Silencing Technique

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Xiaoheng Chen ◽  
Shuo Qi ◽  
Zhe Li ◽  
Bei He ◽  
Hui long Li ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Mtt Assay ◽  
Synergistic Effects ◽  
Inhibitory Effect ◽  
Vascular Endothelial ◽  
Vegf Gene ◽  
Anticancer Properties ◽  
L Cells ◽  
Shenqi Fuzheng Injection ◽  
Endothelial Growth Factor

Shenqi Fuzheng Injection (SFI) is a traditional Chinese medicine injection with anticancer properties and is mainly composed of ginseng and astragalus. Its efficacy has been confirmed in clinical trials, but the mechanism remains unclear. We investigated the effect of SFI on vascular endothelial growth factor (VEGF) gene expression in hepatocellular carcinoma (HCC) cells and identified its possible mechanism of synergistic effects when combined with the chemotherapeutic drug interferon (IFN-) α. An MTT assay was used to measure the inhibition effects of low-dose IFN-α (6000 IU) with or without SFI (0.5 g/L) on the HCC cell line MHCC97. VEGF-silenced MHCC97L-mir200 cell lines were prepared using lentiviral vectors and evaluated by real-time PCR to determine the inhibition effect. We examined MHCC97L-mir200 and MHCC97L cells by MTT assay, using IFN-α alone or in combination with SFI. The inhibition ratio of IFN-α (6000 IU) was -29.5%, while that for IFN-α (6000 IU) + SFI (0.5 g/L) was 17.0%, which was significantly higher than that for the IFN-α group (P < 0.01). The VEGF gene was silenced successfully in MHCC97-L cells. After interference of VEGF, the inhibition by SFI and IFN-α in MHCC97L-mir200 did not differ from that in MHCC97-L cells (P > 0.05). SFI can reduce the expression of VEGF in HCC, which can increase the efficacy of IFN-α, providing a theoretical basis for clinical application.

scholarly journals The Inhibitory Effect of Celangulin V on the ATP Hydrolytic Activity of the Complex of V-ATPase Subunits A and B in the Midgut of Mythimna separata

Toxins ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 130
Author(s):  
Liwen Ding ◽  
Zongxin Guo ◽  
Hang Xu ◽  
Tie Li ◽  
Yuanyuan Wang ◽  
...  
Keyword(s):  
Atp Hydrolysis ◽  
Insect Pests ◽  
Feedback Inhibition ◽  
Hydrolytic Activity ◽  
Inhibitory Effect ◽  
Toxic Activity ◽  
Atp Binding Site ◽  
Insecticidal Effect ◽  
Atpase Subunits ◽  
Mechanism Of Interaction

Celangulin V (CV) is a compound isolated from Celastrus angulatus Max that has a toxic activity against agricultural insect pests. CV can bind to subunits a, H, and B of the vacuolar ATPase (V-ATPase) in the midgut epithelial cells of insects. However, the mechanism of action of CV is still unclear. In this study, the soluble complex of the V-ATPase A subunit mutant TSCA which avoids the feedback inhibition by the hydrolysate ADP and V-ATPase B subunit were obtained and then purified using affinity chromatography. The H+K+-ATPase activity of the complex and the inhibitory activity of CV on ATP hydrolysis were determined. The results suggest that CV inhibits the ATP hydrolysis, resulting in an insecticidal effect. Additionally, the homology modeling of the AB complex and molecular docking results indicate that CV can competitively bind to the AB complex at the ATP binding site, which inhibits ATP hydrolysis. These findings suggest that the AB subunits complex is one of the potential targets for CV and is important for understanding the mechanism of interaction between CV and V-ATPase.

scholarly journals Antiviral Effect of Caulerpin Against Chikungunya

2019 ◽  
Vol 14 (10) ◽  
pp. 1934578X1987829 ◽  
Author(s):  
Priscilla O. Esteves ◽  
Mariana C. de Oliveira ◽  
Caroline de Souza Barros ◽  
Claudio C. Cirne-Santos ◽  
Valeria T. Laneuvlille ◽  
...  
Keyword(s):  
Green Alga ◽  
Biological Activities ◽  
Antiviral Effect ◽  
Vero Cells ◽  
Inhibitory Effect ◽  
Marine Products ◽  
Low Cytotoxicity ◽  
Inhibitory Potential ◽  
Isolated Compound ◽  
Therapy Studies

The discovery of new substances that present innumerable biological activities for the development of drugs is increasingly difficult. Natural marine products are a source of substances with a diversified chemical structure, a broad spectrum of biological activities and low cytotoxicity, which are the essential characteristics for the development of a new drug. An increasing number of reports of Chikungunya virus (CHIKV) infections, in addition to the lack of specific antiviral therapy or vaccines, emphasizes the importance of searching for effective therapy. Studies with the marine green alga Caulerpa racemosa showed antiviral potential. Hence, the aim of this work was to evaluate the anti-CHIKV activity of a marine alkaloid isolated from green alga C. racemosa. Vero cells were used in antiviral assays, submitted to CHIKV, and treated with different concentrations of caulerpin. In the antiviral activity, we observed that the isolated compound showed a much significant and promising EC50 inhibitory effect of 0.8 µM. When evaluating the virucidal activity, we observed that caulerpin was very efficient against CHIKV, being able to inhibit around 90% of the viral infectivity when treated with 5 μM of the compound. We observed that caulerpin added at times 0, 1, 2, and 3 postinfection still maintains a 100% inhibitory potential of viral replication for CHIKV. These studies suggest that the said compounds might be potentially studied for use in the prevention and treatment of CHIKV infections. Derivatives can be considered as a promising new anti-CHIKV drug and can be used for clinical testing.

scholarly journals CD33 (Siglec-3) Inhibitory Function: Role in the NKG2D/DAP10 Activating Pathway

2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Trinidad Hernández-Caselles ◽  
Rubén Corral-San Miguel ◽  
Antonio José Ruiz-Alcaraz ◽  
Pilar García-Peñarrubia
Keyword(s):  
Nk Cells ◽  
Innate Immune ◽  
Inhibitory Receptor ◽  
Inhibitory Function ◽  
Activating Receptors ◽  
Self Tolerance ◽  
Lower Extent ◽  
Low Cytotoxicity ◽  
High Cytotoxicity

CD33 (siglec-3), a well-known target in leukemia therapy, is an inhibitory sialoadhesin expressed in human leukocytes of the myeloid lineage and some lymphoid subsets, including NK cells. It may constitute a control mechanism of the innate immune system; nevertheless, its role as an inhibitory receptor remains elusive. Using human NK cells as a cellular model, we analyzed CD33 inhibitory function upon different activating receptors. In high-cytotoxicity NKL cells, CD33 displayed a prominent inhibition on cytotoxicity triggered by the activating receptors NKG2D and, in a lower extent, 2B4, whereas it did not inhibit NKp46-induced cytotoxicity. NKp46 was partially inhibited by CD33 only when low-cytotoxicity NKL cells were tested. CD33 triggering did not inhibit IFN-γsecretion, contrasting with ILT-2 and CD94/NKG2A inhibitory receptors that inhibited cytotoxicity and IFN-γsecretion induced by all activating receptors tested. CD33-mediated inhibition of NKG2D-induced triggering involved Vav1 dephosphorylation. Our results support the role of CD33 as an inhibitory receptor preferentially regulating the NKG2D/DAP10 cytotoxic signaling pathway, which could be involved in self-tolerance and tumor and infected cell recognition.

scholarly journals Inhibitory effect of Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum

2010 ◽  
Vol 40 (No. 4) ◽  
pp. 128-134 ◽  
Author(s):  
H. Bryk ◽  
B. Dyki ◽  
P. Sobiczewski
Keyword(s):  
Botrytis Cinerea ◽  
Spore Germination ◽  
Germ Tube ◽  
Inhibitory Effect ◽  
Penicillium Expansum ◽  
Bacterial Strains ◽  
Liquid Cultures ◽  
Pseudomonas Spp ◽  
Apple Leaves ◽  
Germ Tube Elongation

The influence of antagonistic Pseudomonas spp. on the development of Botrytis cinerea and Penicillium expansum was studied in liquid cultures. Two strains of Pseudomonas spp. (B194 and B224), originally isolated from apple leaves and fruits, respectively, inhibited spore germination and germ tube elongation of B. cinerea or P. expansum. The inhibitory effect depended on the concentration of bacteria in the cultures. After a prolonged time of incubation (48&ndash;76 h) lysis and fragmentation of hyphae of both fungi was observed. In some cases the hyphae of B. cinerea developed abnormally if the bacterial strains were present &ndash; the hyphal tips were swollen and ball-shaped spore-like structures aggregated in chains were formed.

scholarly journals Rhynchophylline Protects Cultured Rat Neurons against Methamphetamine Cytotoxicity

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Dan Dan Xu ◽  
Robin Hoeven ◽  
Rong Rong ◽  
William Chi-Shing Cho
Keyword(s):  
Mtt Assay ◽  
Neuronal Death ◽  
Time Course ◽  
Inhibitory Effect ◽  
Neuroprotective Activity ◽  
Free Calcium ◽  
Neuronal Cultures ◽  
Death Time ◽  
Free Calcium Concentration

Rhynchophylline (Rhy) is an active component isolated from species of the genusUncariawhich has been used for the treatment of ailments to the central nervous system in traditional Chinese medicine. Besides acting as a calcium channel blocker, Rhy was also reported to be able to protect against glutamate-induced neuronal death. We thus hypothesize that Rhy may have neuroprotective activity against methamphetamine (MA). The primary neurons were cultured directly from the cerebral cortex of neonatal rats, acting asin vitromodel in the present study. The neurotoxicity of MA and the protective effect of Rhy were evaluated by MTT assay. The effects of MA, Rhy or their combination on intracellular free calcium concentration ([Ca2+]i) were determined in individual neocortical neurons by the Fluo-3/AM tracing method. The MTT assay demonstrated that MA has a dose-dependent neurotoxicity in neuronal cultures. The addition of Rhy prior to the exposure to MA prevented neuronal death. Time course studies with the Fluo-3/AM probe showed that Rhy significantly decreased neuronal [Ca2+]iwhich was elevated by the exposure to MA. Our results suggested that Rhy can protect the neuronal cultures against MA exposure and promptly attenuate intracellular calcium overload triggered by MA challenge. This is the first report demonstrating an inhibitory effect of Rhy against MA impairment in cultured neuronsin vitro.

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