scholarly journals Synthetic bovine lactoferrin peptide Lfampin kills Entamoeba histolytica trophozoites by necrosis and resolves amoebic intracecal infection in mice

2019 ◽  
Vol 39 (1) ◽  
Author(s):  
César Díaz-Godínez ◽  
Ximena González-Galindo ◽  
Thuluz Meza-Menchaca ◽  
Raúl J. Bobes ◽  
Mireya de la Garza ◽  
...  

AbstractAmoebiasis caused by the protozoan parasite Entamoeba histolytica remains a public health problem in developing countries, making the identification of new anti-amoebic compounds a continuing priority. Previously, we have shown that lactoferrin (Lf) and several Lf-derived peptides exhibit in vitro anti-amoebic activity independently of their iron-binding activity. Here, we evaluated the amoebicidal effect of synthetic Lf-derived peptides Lfcin-B, Lfcin 17-30, and Lfampin, analyzed the mechanism of death induced by the peptides and determined their therapeutic effects on murine intestinal amoebiasis. MTT assays in trophozoite cultures of E. histolytica exposed to each peptide (1–1000 μM) showed that Lfampin is far more amoebicidal than Lfcins. Lfampin killed 80% of trophozoites at doses higher than 100 μM in 24 h, and FACs analysis using Annexin V/propidium iodide showed that death occurred mainly by necrosis. In contrast, Lfcin-B and Lfcin 17-30 appeared to have no significant effect on amoebic viability. FACs and confocal microscopy analysis using FITC-labeled peptides showed that all three peptides are internalized by the amoeba mainly using receptor (PI3K signaling) and actin-dependent pathways but independent of clathrin. Docking studies identified cholesterol in the amoeba’s plasma membrane as a possible target of Lfampin. Oral treatment of intracecally infected mice with the abovementioned peptides at 10 mg/kg for 4 days showed that Lfampin resolved 100% of the cases of intestinal amoebiasis, whereas Lfcin 17-30 and Lfcin-B were effective in resolving infection in 80 and 70% of cases, respectively. These data show that although synthetic bovine Lf-derived peptides exhibit varying amoebicidal potentials in vitro, they do resolve murine intestinal amoebiasis efficiently, suggesting that they may be useful as a therapeutic treatment.

2021 ◽  
Vol 23 (Supplement_2) ◽  
pp. ii34-ii34
Author(s):  
S G Schwab ◽  
K Sarnow ◽  
E Alme ◽  
R Goldbrunner ◽  
H Bjørsvik ◽  
...  

Abstract BACKGROUND Although withdrawn from the market due to cardiotoxicity, we have shown that the antipsychotic drug Thioridazine shows chemosensitizing effects in combination with Temozolomide (TMZ) for the treatment of glioblastoma multiforme (GBM). Based on our prior observations, the aim of the presented project was through medicinal chemistry, to design and synthesize new compounds based on Thioridazines tricyclic structure, and to determine their therapeutic potential. MATERIAL AND METHODS Fourteen compounds were synthesized where variations were made within the tricyclic side chains. The newly synthesized compounds were screened for therapeutic efficacy with or without TMZ using a WST-1 cell viability assay as well as a real-time imaging system (IncuCyte). Tests were performed on both monolayer cell cultures, as well as on glioma stem cell spheroids (GSC). The therapeutic effects were also studied on human astrocytes (NHA) as well as on rat brain organoids (BO). Annexin V/propidium iodide (PI) double staining followed by flow cytometric analysis was performed after 48 hours of treatment. RESULTS Following an extensive screening, we identified two novel compounds (EA01 and EA02) that at concentrations of 4 and 9.5 µM showed a strong cytotoxicity on GBM cell lines (U-87 MG p<0,0001, U251 p<0,0001, LN18 p=0,0004) as well as on glioma stem cells (GSC) (P3 p<0,0001) compared to NHA and BOs respectively. Also, when BOs were confronted with GSC spheres in an invasion assay, a selective cytotoxicity was observed in the GSCs. Mechanistically, we show that both compounds induce apoptosis in the GBM cells. Moreover, intravenous delivery of increasing concentrations of EA01 and EA02 revealed no toxicity in animals at concentrations up to 21 mg/kg. CONCLUSION We have developed two new tricyclic therapeutic compounds that show a strong selective cytotoxicity in GBM cells with limited systemic toxicity in animals. Ongoing studies are investigating the therapeutic potential of EA01 and EA02 in orthotopic xenografts in vivo.


Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2464
Author(s):  
Ramiro Quintanilla-Licea ◽  
Javier Vargas-Villarreal ◽  
María Julia Verde-Star ◽  
Verónica Mayela Rivas-Galindo ◽  
Ángel David Torres-Hernández

Amebiasis caused by Entamoeba histolytica is nowadays a serious public health problem worldwide, especially in developing countries. Annually, up to 100,000 deaths occur across the world. Due to the resistance that pathogenic protozoa exhibit against commercial antiprotozoal drugs, a growing emphasis has been placed on plants used in traditional medicine to discover new antiparasitics. Previously, we reported the in vitro antiamoebic activity of a methanolic extract of Lippia graveolens Kunth (Mexican oregano). In this study, we outline the isolation and structure elucidation of antiamoebic compounds occurring in this plant. The subsequent work-up of this methanol extract by bioguided isolation using several chromatographic techniques yielded the flavonoids pinocembrin (1), sakuranetin (2), cirsimaritin (3), and naringenin (4). Structural elucidation of the isolated compounds was achieved by spectroscopic/spectrometric analyses and comparing literature data. These compounds revealed significant antiprotozoal activity against E. histolytica trophozoites using in vitro tests, showing a 50% inhibitory concentration (IC50) ranging from 28 to 154 µg/mL. Amebicide activity of sakuranetin and cirsimaritin is reported for the first time in this study. These research data may help to corroborate the use of this plant in traditional Mexican medicine for the treatment of dyspepsia.


2020 ◽  
Vol 21 (5) ◽  
pp. 1817 ◽  
Author(s):  
Ming-Yu Song ◽  
Qiu-Rui He ◽  
Yi-Lin Wang ◽  
Hao-Ran Wang ◽  
Tian-Cheng Jiang ◽  
...  

Combretastatin-4 (CA-4) as a tubulin polymerization inhibitor draws extensive attentions. However, due to its weak stability of cis-olefin and poor metabolic stability, structure modifications on cis-configuration are being performed. In this work, we constructed a series of novel CA-4 analogues with linkers on olefin containing diphenylethanone, cis-locked dihydrofuran, α-substituted diphenylethanone, cyclobutane and cyclohexane on its cis-olefin. Cytotoxic activity of all analogues was measured by an SRB assay. Among them, compound 6b, a by-product in the preparation of diphenylethanone analogues, was found to be the most potent cytotoxic agents against HepG2 cells with IC50 values of less than 0.5 μM. The two isomers of 6b induced cellular apoptosis tested by Annexin V-FITC and propidium iodide (PI) double staining, arrested cells in the G2/M phase by PI staining analysis, and disrupted microtubule network by immunohistochemistry study in HepG2 cells. Moreover, 6b-(E) displayed a dose-dependent inhibition effect for tubulin assembly in in vitro tubulin polymerization assay. In addition, molecular docking studies showed that two isomers of 6b could bind efficiently at colchicine binding site of tubulin similar to CA-4.


2018 ◽  
Vol 36 (5_suppl) ◽  
pp. 32-32
Author(s):  
Yaya Chu ◽  
Nang Kham Su ◽  
Sarah Alter ◽  
Emily Jeng ◽  
Peter R. Rhode ◽  
...  

32 Background: Patients retreated with rituximab often relapse which limit patient treatment options (Goldman/Cairo, Leukemia, 2013). Our group has successfully expanded functional and active peripheral blood NK cells (exPBNK) to target BL (Chu/Cairo, et al, Can Imm Res, 2015). 2B8T2M was generated by fusing ALT-803, an IL-15 superagonist, to four single-chains of rituximab (Liu/Wong, et al, JBC, 2016). 2B8T2M displayed tri-specific CD20 binding activity, activated NK cells to enhance antibody-dependent cellular cytotoxicity, and induced apoptosis of B-lymphoma cells (Liu/Wong, et al, JBC, 2016). Methods: ALT-803 and 2B8T2M were generously provided by Altor BioScience Corporation. NK expansion, NK receptors expression and cytotoxicity were examined as we previous described (Chu/Cairo, et al, Can Imm Res 2015). IFNg and granzyme B levels were examined by ELISA assays. Equal doses of IgG, Rituximab, ALT-803, Rituximab+ALT-803, obinutuzumab (obinu, generously provided by Christian Klein, PhD from Roche) were used for comparison. Results: 2B8T2M significantly enhanced exPBNK cytotoxicity against rituximab-sensitive Raji cells compared to the controls IgG, Rituximab, ALT-803, Rituximab+ALT-803, obinu (p < 0.001, E:T = 1:1). 2B8T2M also significantly enhanced exPBNK cytotoxicity against rituximab-resistant Raji-2R cells (p < 0.001, E:T = 1:1) and resistant Raji-4RH cells (p < 0.001, E:T = 1:1). Furthermore, 2B8T2M significantly enhanced IFN-g and granzyme B production from exPBNK against Raji, Raji-2R and Raji-4RH compared to IgG (p < 0.001), rituximab (p < 0.001), ALT-803 (p < 0.001), Rituximab+ALT-803 (p < 0.001), and obinutuzumab (p < 0.001). Conclusions: 2B8T2M compared to rituximab, ALT-803 or obinutuzumab significantly enhanced exPBNK in vitro cytotoxicity against rituximab-sensitive and –resistant BL cells. The in vivo functions of 2B8T2M with exPBNK using humanized NSG models are under investigation.


2010 ◽  
Vol 29 (3) ◽  
pp. 199-212 ◽  
Author(s):  
DM de Oliveira ◽  
BPS Pitanga ◽  
MS Grangeiro ◽  
RMF Lima ◽  
MFD Costa ◽  
...  

The exposure to benzene is a public health problem. Although the most well-known effect of benzene is hematopoietic toxicity, there is little information about the benzene and its metabolites effects on the central nervous system (CNS). This study examined the toxic effects of 1,2-dihydroxybenzene (catechol), a benzene metabolite, to human glioblastoma GL-15 cells. GL-15 cell cultures were used as a model to provide more information about the toxic effects of aromatic compounds to the CNS. Catechol induced time- and concentration-dependent cytotoxic effects. Morphological changes, such as the retraction of the cytoplasm and chromatin clumping, were seen in cells exposed to 200 μM catechol for 48 hours. In cells exposed to 600 μM catechol for 48 hours, 78.0% of them presented condensed nuclei, and the Comet assay showed DNA damage. The percentage of cells labeled with annexin V (apoptotic cells) was greater in the group exposed to catechol (20.7%) than in control cells (0.4%). Exposure to catechol at concentrations greater than 100 μM enhanced Bax levels, and a decrease in Bcl-2 level was observed after the exposure to 600 μM catechol for 48 hours. Furthermore, catechol depleted reduced glutathione. Hence, catechol induced cell death mainly by apoptosis.


2018 ◽  
Vol 48 (2) ◽  
pp. 765-772 ◽  
Author(s):  
Juan Jin ◽  
Kang Hu ◽  
Meiyu Ye ◽  
Diandian Wu ◽  
Qiang  He

Background/Aims: The purpose of this study was to investigate the impact of rapamycin (RAP) on autophagy in podocytes and the therapeutic effects of RAP on idiopathic membranous nephropathy (IMN). Methods: We established an in vitro model of IMN by preconditioning mouse podocytes with puromycin aminonucleoside (PAN). A Cell Counting Kit-8 was used to detect the proliferation of each group of podocytes. Podocyte apoptosis was analyzed by flow cytometry via annexin V/propidium iodide dual staining. Subsequently, we observed the number of autophagosomes by transmission electron microscopy. Western blotting was used to detect the levels of LC3, mTOR, p-mTOR, 4EBP1, p-4EBP1, P70S6K, and p-P70S6K in each group. Results: The number of podocytes in the PAN + 100 ng/mL RAP group, PAN + 200 ng/mL RAP group, and PAN + 300 ng/mL RAP group was significantly increased (P < 0.01). The apoptotic rate of podocytes was significantly different between the PAN group and the PAN + RAP group (P < 0.001). There were fewer autophagic corpuscles in the PAN group and more autophagosomes were observed in the PAN + RAP group. LC3 protein expression was down-regulated in the PAN group, while its expression was up-regulated in the PAN + RAP group. In the PAN group, the levels of phosphorylated mTOR, 4EBP1, and P70S6K were increased, while in the PAN + RAP group, protein phosphorylation was reduced. Conclusions: RAP can effectively inhibit the mTOR/P70S6K/4EBP1 signaling pathway, and activate podocyte autophagy, consequently reducing podocyte apoptosis. Therefore, RAP could be used for the treatment of idiopathic membranous nephropathy.


2012 ◽  
Vol 90 (3) ◽  
pp. 435-441 ◽  
Author(s):  
Nidia León-Sicairos ◽  
Leonardo Martínez-Pardo ◽  
Beatriz Sánchez-Hernández ◽  
Mireya de la Garza ◽  
Julio César Carrero

Entamoeba histolytica is a protozoan parasite that causes amoebiasis, an illness that affects many people around the world. We have previously reported that lactoferrin is able to kill E. histolytica in in vitro cultures. The aim of the present study was to evaluate the therapeutic effect of orally administered bovine lactoferrin in the control of intestinal amoebiasis of susceptible C3H/HeJ mice. The results showed that 20 mg lactoferrin/kg orally administered each day for 1 week was able to eliminate the infection in 63% of the mice, since neither trophozoites nor evidence of epithelial damage and (or) swelling were found in tissue sections of the cecum. The rest of the treated animals (37%) showed a decrease in trophozoite numbers and mucus secreted to the lumen, as compared with untreated and infected mice (p < 0.05). By immunohistochemistry, the profile of secreted cytokines in the cecum revealed that infected but untreated animals showed a mixed Th1/regulatory cytokines profile, whereas the cecum of mice treated (cured) showed a Th2 cytokine profile (IL-4) and expression of the multifunctional IL-6. In addition, cytokines and increasing cecal production of total IgA antibodies were found associated with little inflammation and disease control observed in the cecum of lactoferrin-treated animals. These results suggest that oral administration of lactoferrin can control intestinal amoebic infection probably by killing amoebas or favoring their removal and reestablish the antiinflammatory intestinal environment.


2020 ◽  
Vol 20 (3) ◽  
pp. 182-191 ◽  
Author(s):  
Aldo S. de Oliveira ◽  
David L. Palomino-Salcedo ◽  
Eduardo Zapp ◽  
Daniela Brondani ◽  
Thaynara D. Hoppe ◽  
...  

Background: In general, fungal species are characterized by their opportunistic character and can trigger various infections in immunocompromised hosts. The emergence of infections associated with high mortality rates is due to the resistance mechanisms that these species develop. Methods: This phenomenon of resistance denotes the need for the development of new and effective therapeutic approaches. In this paper, we report the investigation of the antioxidant and antifungal behavior of dimeric naphthoquinones derived from lawsone whose antimicrobial and antioxidant potential has been reported in the literature. Results: Seven fungal strains were tested, and the antioxidant potential was tested using the combination of the methodologies: reducing power, total antioxidant capacity and cyclic voltammetry. Molecular docking studies (PDB ID 5V5Z and 1EA1) were conducted which allowed the derivation of structureactivity relationships (SAR). Compound 1-i, derived from 3-methylfuran-2-carbaldehyde showed the highest antifungal potential with an emphasis on the inhibition of Candida albicans species (MIC = 0.5 µg/mL) and the highest antioxidant potential. Conclusion: A combination of molecular modeling data and in vitro assays can help to find new solutions to this major public health problem.


2020 ◽  
Vol 11 ◽  
Author(s):  
Ya-yi Jiang ◽  
Jia-cheng Shui ◽  
Bo-xun Zhang ◽  
Jia-wei Chin ◽  
Ren-song Yue

Type 2 diabetes mellitus (T2DM) is a chronic disease that has become a global public health problem. Studies on T2DM prevention and treatment mostly focus on discovering therapeutic drugs. Artemisinin and its derivatives were originally used as antimalarial treatments. In recent years, the roles of artemisinins in T2DM have attracted much attention. Artemisinin treatments not only attenuate insulin resistance and restore islet ß-cell function in T2DM but also have potential therapeutic effects on diabetic complications, including diabetic kidney disease, cognitive impairment, diabetic retinopathy, and diabetic cardiovascular disease. Many in vitro and in vivo experiments have confirmed the therapeutic utility of artemisinin and its derivatives on T2DM, but no article has systematically demonstrated the specific role artemisinin plays in the treatment of T2DM. This review summarizes the potential therapeutic effects and mechanism of artemisinin and its derivatives in T2DM and associated complications, providing a reference for subsequent related research.


2021 ◽  
Author(s):  
Spencer B. Huggett ◽  
Jeffrey S. Hatfield ◽  
Joshua D. Walters ◽  
John E. McGeary ◽  
Justine W. Welsh ◽  
...  

ABSTRACTCocaine use presents a worldwide public health problem with high socioeconomic cost. Current treatments for cocaine use disorder (CUD) are suboptimal and rely primarily on behavioral interventions. To explore pharmaceutical treatments for CUD, we analyzed genome-wide gene expression data from publically availble human brain tissues (midbrain, hippocampus and prefrontal cortex neurons) from 71 individuals (mean age = 39.9, 100% male, 36 with CUD and 35 matched controls). We leveraged the L1000 database to investigate molecular associations between neuronal mRNA profiles from 825 repurposable compounds (e.g., FDA approved) with human CUD gene expression in the brain. We identified 16 compounds that were negatively associated with CUD gene expression patterns across all brain regions (padj < 0.05), all of which outperformed current targets undergoing clinical trials for CUD (all padj > 0.05). We tested the effectiveness of these compounds using independent transcriptome-wide in vitro (neuronal cocaine exposure; n=18) and in vivo (mouse cocaine self-administration; prefrontal cortex, hippocampus and midbrain; n = 12-15) datasets. Among these medications, Ibrutinib demonstrated negative associations with both neuronal cocaine exposure and mouse cocaine self-administration. To obtain experimental confirmation of therapeutic effects of Ibrutinib on CUD, we used the Drosophila melanogaster model, which enables highthroughput quantification of behavioral responses in defined genetic backgrounds and controlled environmental conditions. Ibrutinib altered cocaine-induced changes in startle response and reduced the occurrence of cocaine-induced seizures (n = 61-142 per group; sex: 51%female). Our results identify Ibrutinib, an FDA approved medication, as a potential therapeutic for cocaine neurotoxicity.


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