scholarly journals A Sphingolipid Inhibitor Induces a Cytokinesis Arrest and Blocks Stage Differentiation in Giardia lamblia

2007 ◽  
Vol 52 (2) ◽  
pp. 563-569 ◽  
Author(s):  
Sabrina Sonda ◽  
Saša Štefanić ◽  
Adrian B. Hehl
Keyword(s):  
Giardia Lamblia ◽  
Cell Metabolism ◽  
Microscopic Analysis ◽  
Dependent Manner ◽  
Promising Target ◽  
Proliferation And Differentiation ◽  
Parasite Stage ◽  
Specific Stage ◽  
Parasite Replication

ABSTRACT Sphingolipid biosynthesis pathways have recently emerged as a promising target for therapeutic intervention against pathogens, including parasites. A key step in the synthesis of complex sphingolipids is the glucosylation of ceramide, mediated by glucosylceramide (GlcCer) synthase, whose activity can be inhibited by PPMP (1-phenyl-2-palmitoylamino-3-morpholino-1-propanol). In this study, we investigated whether PPMP inhibits the proliferation and differentiation of the pathogenic parasite Giardia lamblia, the major cause of parasite-induced diarrhea worldwide. PPMP was found to block in vitro parasite replication in a dose-dependent manner, with a 50% inhibitory concentration of 3.5 μM. The inhibition of parasite replication was irreversible at 10 μM PPMP, a concentration that did not affect mammalian cell metabolism. Importantly, PPMP inhibited the completion of cell division at a specific stage in late cytokinesis. Microscopic analysis of cells incubated with PPMP revealed the aberrant accumulation of cellular membranes belonging to the endoplasmic reticulum network in the caudal area of the parasites. Finally, PPMP induced a 90% reduction in G. lamblia differentiation into cysts, the parasite stage responsible for the transmission of the disease. These results show that PPMP is a powerful inhibitor of G. lamblia in vitro and that as-yet-uncharacterized sphingolipid biosynthetic pathways are potential targets for the development of anti-G. lamblia agents.

scholarly journals Antiobesity Effects of Extract from Spergularia marina Griseb in Adipocytes and High-Fat Diet-Induced Obese Rats

Nutrients ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 336 ◽  
Author(s):  
Yong-Hyun Park ◽  
Jae-Joon Lee ◽  
Hee-Kyoung Son ◽  
Bok-Hee Kim ◽  
Jaemin Byun ◽  
...  
Keyword(s):  
Ethanol Extract ◽  
Health Concern ◽  
Dependent Manner ◽  
High Fat ◽  
Proliferation And Differentiation ◽  
Obese Rats ◽  
Spergularia Marina ◽  
Natural Herb

Obesity has recently risen and become a serious health concern in Korea according to the westernized diet and altered lifestyle. Hence, there is a growing interest in the supplementation of phytochemicals to find a safe and effective functional ingredient to treat obesity. Spergularia marina Griseb (SM) has traditionally been used as a natural herb against chronic diseases in Korea. In this study, we investigated the antiobesity effects of SM in vitro and in vivo. SM ethanol extract (SME) inhibited proliferation and differentiation in murine adipocytes and primary porcine pre-adipocytes in a dose-dependent manner. In the in vivo study, supplementation of SM powder (SMP) remarkably attenuated fat accumulation in HFD-induced obese rats. In addition, SMP supplementation improved lipid profiles in the serum and tissues of high-fat induced obese rats. Collectively, these data indicated that SME exhibited antiobesity effects by modulating adipogenesis and lipolysis. Furthermore, SMP could be developed as an obesity-induced metabolic syndrome treatment.

scholarly journals Motility patterns of Trypanosoma cruzi trypomastigotes correlate with the efficiency of parasite invasion in vitro

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jorge A. Arias-del-Angel ◽  
Jesús Santana-Solano ◽  
Moisés Santillán ◽  
Rebeca G. Manning-Cela
Keyword(s):  
Trypanosoma Cruzi ◽  
Cell Line ◽  
Mammalian Cells ◽  
Dependent Manner ◽  
Parasite Invasion ◽  
Mammalian Cell Cultures ◽  
A Cell ◽  
Parasite Replication ◽  
Parasite Motility

Abstract Numerous works have demonstrated that trypanosomatid motility is relevant for parasite replication and sensitivity. Nonetheless, although some findings indirectly suggest that motility also plays an important role during infection, this has not been extensively investigated. This work is aimed at partially filling this void for the case of Trypanosoma cruzi. After recording swimming T. cruzi trypomastigotes (CL Brener strain) and recovering their individual trajectories, we statistically analyzed parasite motility patterns. We did this with parasites that swim alone or above monolayer cultures of different cell lines. Our results indicate that T. cruzi trypomastigotes change their motility patterns when they are in the presence of mammalian cells, in a cell-line dependent manner. We further performed infection experiments in which each of the mammalian cell cultures were incubated for 2 h together with trypomastigotes, and measured the corresponding invasion efficiency. Not only this parameter varied from cell line to cell line, but it resulted to be positively correlated with the corresponding intensity of the motility pattern changes. Together, these results suggest that T. cruzi trypomastigotes are capable of sensing the presence of mammalian cells and of changing their motility patterns accordingly, and that this might increase their invasion efficiency.

scholarly journals Giardial Triosephosphate Isomerase as Possible Target of the Cytotoxic Effect of Omeprazole in Giardia lamblia

2014 ◽  
Vol 58 (12) ◽  
pp. 7072-7082 ◽  
Author(s):  
Horacio Reyes-Vivas ◽  
Ignacio de la Mora-de la Mora ◽  
Adriana Castillo-Villanueva ◽  
Lilian Yépez-Mulia ◽  
Gloria Hernández-Alcántara ◽  
...  
Keyword(s):  
Giardia Lamblia ◽  
Cytotoxic Effect ◽  
Triosephosphate Isomerase ◽  
Glycolytic Enzyme ◽  
Cysteine Residue ◽  
Enzyme Inactivation ◽  
Dependent Manner ◽  
Drug Resistant ◽  
Content Type

ABSTRACTGiardiasis is highly prevalent in the developing world, and treatment failures with the standard drugs are common. This work deals with the proposal of omeprazole as a novel antigiardial drug, focusing on a giardial glycolytic enzyme used to follow the cytotoxic effect at the molecular level. We used recombinant technology and enzyme inactivation to demonstrate the capacity of omeprazole to inactivate giardial triosephosphate isomerase, with no adverse effects on its human counterpart. To establish the specific target in the enzyme, we used single mutants of every cysteine residue in triosephosphate isomerase. The effect on cellular triosephosphate isomerase was evaluated by following the remnant enzyme activity on trophozoites treated with omeprazole. The interaction of omeprazole with giardial proteins was analyzed by fluorescence spectroscopy. The susceptibility to omeprazole of drug-susceptible and drug-resistant strains ofGiardia lambliawas evaluated to demonstrate its potential as a novel antigiardial drug. Our results demonstrate that omeprazole inhibits giardial triosephosphate isomerase in a species-specific manner through interaction with cysteine at position 222. Omeprazole enters the cytoplasmic compartment of the trophozoites and inhibits cellular triosephosphate isomerase activity in a dose-dependent manner. Such inhibition takes place concomitantly with the cytotoxic effect caused by omeprazole on trophozoites.G. lambliatriosephosphate isomerase (GlTIM) is a cytoplasmic protein which can help analyses of how omeprazole works against the proteins of this parasite and in the effort to understand its mechanism of cytotoxicity. Our results demonstrate the mechanism of giardial triosephosphate isomerase inhibition by omeprazole and show that this drug is effectivein vitroagainst drug-resistant and drug-susceptible strains ofG. lamblia.

scholarly journals β-Chemokines Enhance Parasite Uptake and Promote Nitric Oxide-Dependent Microbiostatic Activity in Murine Inflammatory Macrophages Infected with Trypanosoma cruzi

1999 ◽  
Vol 67 (9) ◽  
pp. 4819-4826 ◽  
Author(s):  
Júlio C. S. Aliberti ◽  
Fabiana S. Machado ◽  
Janeusa T. Souto ◽  
Ana P. Campanelli ◽  
Mauro M. Teixeira ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Neutralizing Antibodies ◽  
Specific Inhibitor ◽  
No Production ◽  
Dependent Manner ◽  
Macrophage Infection ◽  
Parasite Replication ◽  
Ifn Γ

ABSTRACT In the present study, we describe the ability of Trypanosoma cruzi trypomastigotes to stimulate the synthesis of β-chemokines by macrophages. In vivo infection with T. cruzi led to MIP-1α, RANTES, and JE/MCP1 mRNA expression by cells from peritoneal inflammatory exudate. In addition, in vitro infection with T. cruzi resulted in expression of β-chemokine MIP-1α, MIP-1β, RANTES, and JE mRNA by macrophages. The expression of the β-chemokine MIP-1α, MIP-1β, RANTES, and JE proteins by murine macrophages cultured with trypomastigote forms ofT. cruzi was confirmed by immunocytochemistry. Interestingly, macrophage infection with T. cruzi also resulted in NO production, which we found to be mediated mainly by β-chemokines. Hence, treatment with anti-β-chemokine-specific neutralizing antibodies partially inhibited NO release by macrophages incubated with T. cruzi parasites. Further, the addition of the exogenous β-chemokines MIP-1α, MIP-1β, RANTES, and JE/MCP-1 induced an increased T. cruzi uptake, leading to enhanced NO production and control of parasite replication in a dose-dependent manner. l-NMMA, a specific inhibitor of thel-arginine–NO pathway, caused a decrease in NO production and parasite killing when added to cultures of macrophages stimulated with β-chemokines. Among the β-chemokines tested, JE was more potent in inhibiting parasite growth, although it was much less efficient than gamma interferon (IFN-γ). Nevertheless, JE potentiates parasite killing by macrophages incubated with low doses of IFN-γ. Together, these results suggest that in addition to their chemotactic activity, murine β-chemokines may also contribute to enhancing parasite uptake and promoting control of parasite replication in macrophages and may play a role in resistance to T. cruziinfection.

scholarly journals Perfluorooctane sulfonate affects proliferation and differentiation of pluripotent human teratocarcinoma cells

2016 ◽  
Author(s):  
Mina Popovic ◽  
Brett A Neilan ◽  
Francesco Pomati
Keyword(s):  
Stem Cell ◽  
Cell Model ◽  
Morphological Changes ◽  
Perfluorooctane Sulfonate ◽  
Stem Cell Marker ◽  
Marker Genes ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Proliferation And Differentiation

Perfluorinated compounds have raised concern due to their potential association with detrimental postnatal outcomes in animals and humans. We tested the effects of perfluorooctane sulfonate (PFOS) on a human pluripotent teratocarcinoma (known as NCCIT) cells as an in vitro prototype for developmental toxicity in mammals. NCCIT contains stem-cells able to differentiate into endoderm, mesoderm and ectoderm. We tested our cell model using a teratogenic compound, retinoic acid (RA), a cytotoxin, nocodazole (ND), and PFOS. We assayed cells proliferation, morphology and expression of stem cell and germ layer marker genes. PFOS reduced NCCIT cell proliferation in a concentration-dependent manner and induced morphological changes in cell cultures that resembled ectodermal phenotypes. A tendency towards a differentiated state in NCCIT was confirmed by real-time gene expression. PFOS triggered up-regulation of the gene nestin, indicative of ectodermal lineage differentiation, and interfered with the expression of the pluripotency stem-cell marker TERT. PFOS produced effects on both cells proliferation and differentiation, although not as severe as those observed for RA and ND, at levels that fall within the range of concentrations found in animal and human plasma. We discuss our findings in the context of possible interference of PFOS with the processes governing the early development of mammalian tissues.

Extracellular HMGB1 Enhances Proliferation, Differentiation and Migration of Human CD34+ Hematopoietic Stem Cells in Vitro

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 4744-4744
Author(s):  
Xingbing Wang ◽  
Xin Chen ◽  
Weihua Ren ◽  
Xiucai Xu ◽  
Kaidi Song ◽  
...  
Keyword(s):  
Stem Cells ◽  
Hematopoietic Stem Cells ◽  
Cord Blood ◽  
Dependent Manner ◽  
Hematopoietic Stem ◽  
Human Cd34 ◽  
Proliferation And Differentiation ◽  
Cord Blood Cd34 ◽  
And Migration

Abstract High-mobility group box 1 protein (HMGB1) is a chromatin protein and acts as a cytokine involved in inflammation, cell proliferation, differentiation, migration and stem cell recruitment. So far, little is known about its effect on hematopoietic stem cells (HSCs). In this study, we investigated whether receptors for HMGB1 are expressed on human CD34+ HSCs, and whether HMGB1 could affect HSCs proliferation, differentiation and migration in vitro. As examined by FACS analysis and RT-PCR, cord blood CD34+ HSCs express the HMGB1 receptors RAGE (receptor for advanced glycation end products), TLR2 (Toll-like receptor 2) and TLR4. To study the effects of HMGB1 on CD34+ HSCs proliferation and differentiation, freshly isolated cord blood CD34+ HSCs were cultured for 7 days in medium alone or in the presence of HMGB1. Flow cytometric analysis showed that HMGB1 (50ng/ml) can induce the differentiation of CD34+ HSCs along the granulo-monocytic (CD14+, CD13+) lineage and erythropoiesis (CD71+). In contrast, HMGB1 did not induce the expression of CD41, a marker for megakaryocyte lineage. The numbers of cells cultured in the presence of HMGB1 were always increased in comparison with controls. Furthermore, higher numbers of granulomonocytic progenitors (CFU-GM), erythroid progenitors (BFU-E), and CFU-MIX were confirmed by CFC assays in a HMGB1 dose dependent manner after 14-day culture. The results suggest that HMGB1 enhances CD34+ HSCs proliferation and differentiation. We next assessed the effects of HMGB1 on HSCs migration by chemotaxis assay using Boyden chambers. HMGB1 dose-dependently increased the chemotactic migration of CD34+ HSCs. A neutralizing anti-RAGE antibody significantly blocked the HMGB1-induced migration of HSCs, whereas neutralizing TLR2 and TLR4 antibodies did not significantly influence HMGB1-stimulated HSCs migration, suggesting that the migratory effect of HMGB1 on human HSCs is predominantly mediated by RAGE. In summary, our results provide the first report of HMGB1 receptors expression profile of human cord blood CD34+ HSCs and demonstrate that HMGB1 can increase the proliferation and migration of HSCs and directly induce of HSCs along myeloid differentiation and erythropoiesis in vitro. Further studies will be needed to clarify the mechanism of HMGB1 activation and the physiological function of HMGB1 in HSCs in vivo.

scholarly journals Human Papillomavirus E2 Regulates SRSF3 (SRp20) To Promote Capsid Protein Expression in Infected Differentiated Keratinocytes

2016 ◽  
Vol 90 (10) ◽  
pp. 5047-5058 ◽  
Author(s):  
T. Klymenko ◽  
H. Hernandez-Lopez ◽  
A. I. MacDonald ◽  
J. M. Bodily ◽  
S. V. Graham
Keyword(s):  
Human Papillomavirus ◽  
Life Cycle ◽  
Protein Expression ◽  
Capsid Protein ◽  
Drug Targets ◽  
Cell Metabolism ◽  
Dependent Manner ◽  
Control Activity

ABSTRACTThe human papillomavirus (HPV) life cycle is tightly linked to differentiation of the infected epithelial cell, suggesting a sophisticated interplay between host cell metabolism and virus replication. Previously, we demonstrated in differentiated keratinocytesin vitroandin vivothat HPV type 16 (HPV16) infection caused increased levels of the cellular SR splicing factors (SRSFs) SRSF1 (ASF/SF2), SRSF2 (SC35), and SRSF3 (SRp20). Moreover, the viral E2 transcription and replication factor that is expressed at high levels in differentiating keratinocytes could bind and control activity of the SRSF1 gene promoter. Here, we show that the E2 proteins of HPV16 and HPV31 control the expression of SRSFs 1, 2, and 3 in a differentiation-dependent manner. E2 has the greatest transactivation effect on expression of SRSF3. Small interfering RNA depletion experiments in two different models of the HPV16 life cycle (W12E and NIKS16) and one model of the HPV31 life cycle (CIN612-9E) revealed that only SRSF3 contributed significantly to regulation of late events in the virus life cycle. Increased levels of SRSF3 are required for L1 mRNA and capsid protein expression. Capsid protein expression was regulated specifically by SRSF3 and appeared independent of other SRSFs. Taken together, these data suggest a significant role of the HPV E2 protein in regulating late events in the HPV life cycle through transcriptional regulation of SRSF3 expression.IMPORTANCEHuman papillomavirus replication is accomplished in concert with differentiation of the infected epithelium. Virus capsid protein expression is confined to the upper epithelial layers so as to avoid immune detection. In this study, we demonstrate that the viral E2 transcription factor activates the promoter of the cellular SRSF3 RNA processing factor. SRSF3 is required for expression of the E4^L1 mRNA and so controls expression of the HPV L1 capsid protein. Thus, we reveal a new dimension of virus-host interaction crucial for production of infectious virus. SRSF proteins are known drug targets. Therefore, this study provides an excellent basis for developing strategies to regulate capsid protein production in the infected epithelium and the production of new virions.

scholarly journals Cuprizone-Induced Neurotoxicity in Human Neural Cell Lines Is Mediated by a Reversible Mitochondrial Dysfunction: Relevance for Demyelination Models

2021 ◽  
Vol 11 (2) ◽  
pp. 272
Author(s):  
Eva Martínez-Pinilla ◽  
Núria Rubio-Sardón ◽  
Sandra Villar-Conde ◽  
Gemma Navarro ◽  
Eva del Valle ◽  
...  
Keyword(s):  
Cell Lines ◽  
Cell Metabolism ◽  
In Vitro Models ◽  
Demyelinating Diseases ◽  
New Drugs ◽  
Neural Cells ◽  
Dependent Manner ◽  
Human Neuroblastoma

Suitable in vivo and in vitro models are instrumental for the development of new drugs aimed at improving symptoms or progression of multiple sclerosis (MS). The cuprizone (CPZ)-induced murine model has gained momentum in recent decades, aiming to address the demyelination component of the disease. This work aims at assessing the differential cytotoxicity of CPZ in cells of different types and from different species: human oligodendroglial (HOG), human neuroblastoma (SH-SY5Y), human glioblastoma (T-98), and mouse microglial (N-9) cell lines. Moreover, the effect of CPZ was investigated in primary rat brain cells. Cell viability was assayed by oxygen rate consumption and by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide-based (MTT) method. Our results demonstrated that CPZ did not cause death in any of the assayed cell models but affected mitochondrial function and aerobic cell respiration, thus compromising cell metabolism in neural cells and neuron-glia co-cultures. In this sense, we found differential vulnerability between glial cells and neurons as is the case of the CPZ-induced mouse model of MS. In addition, our findings demonstrated that reduced viability was spontaneous reverted in a time-dependent manner by treatment discontinuation. This reversible cell-based model may help to further investigate the role of mitochondria in the disease, and study the molecular intricacies underlying the pathophysiology of the MS and other demyelinating diseases.

scholarly journals Evaluation of the In Vitro Efficacy of Artemisia annua, Rumex abyssinicus, and Catha edulis Forsk Extracts in Cancer and Trypanosoma brucei Cells

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Netsanet Worku ◽  
Andualem Mossie ◽  
August Stich ◽  
Arwid Daugschies ◽  
Susanne Trettner ◽  
...  
Keyword(s):  
Trypanosoma Brucei ◽  
Artemisia Annua ◽  
Microscopic Analysis ◽  
Growth Inhibitor ◽  
Cell Counting ◽  
Common Mechanism ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Catha Edulis

The current drugs against sleeping sickness are derived from cancer chemotherapeutic approaches. Herein, we aimed at evaluating the in vitro effect of alcoholic extracts of Artemisia annua (AMR), Rumex abyssinicus (RMA), and Catha edulis Forsk (CEF) on proliferation/viability of 1321N1 astrocytoma, MCF-7 breast cancer, THP-1 leukemia, and LNCaP, Du-145, and PC-3 prostate cancer cells and on Trypanosoma brucei cells. Proliferation of tumor cells was evaluated by WST-1 assay and viability/behaviour of T. brucei by cell counting and light microscopy. CEF was the most efficient growth inhibitor in comparison to AMR and RMA. Nevertheless, in LNCaP and THP-1 cells, all extracts significantly inhibited tumor growth at 3 μg/mL. All extracts inhibited proliferation of T. brucei cells in a concentration-dependent manner. Microscopic analysis revealed that 95% of the T. brucei cells died when exposed to 33 μg/mL CEF for 3 hrs. Similar results were obtained using 33 μg/mL AMR for 6 hrs. In case of RMA, however, higher concentrations were necessary to obtain similar effects on T. brucei. This demonstrates the antitumor efficacy of these extracts as well as their ability to dampen viability and proliferation of T. brucei, suggesting a common mechanism of action on highly proliferative cells, most probably by targeting cell metabolism.

scholarly journals Septins promote macropinosome maturation and traffic to the lysosome by facilitating membrane fusion

2016 ◽  
Vol 214 (5) ◽  
pp. 517-527 ◽  
Author(s):  
Lee Dolat ◽  
Elias T. Spiliotis
Keyword(s):  
Cell Metabolism ◽  
Extracellular Fluid ◽  
Fluid Phase ◽  
Endocytic Pathway ◽  
Dependent Manner ◽  
Septin Gtpases ◽  
And Function ◽  
Large Clusters ◽  
Blocking Antibodies

Macropinocytosis, the internalization of extracellular fluid and material by plasma membrane ruffles, is critical for antigen presentation, cell metabolism, and signaling. Macropinosomes mature through homotypic and heterotypic fusion with endosomes and ultimately merge with lysosomes. The molecular underpinnings of this clathrin-independent endocytic pathway are largely unknown. Here, we show that the filamentous septin GTPases associate preferentially with maturing macropinosomes in a phosphatidylinositol 3,5-bisphosphate–dependent manner and localize to their contact/fusion sites with macropinosomes/endosomes. Septin knockdown results in large clusters of docked macropinosomes, which persist longer and exhibit fewer fusion events. Septin depletion and overexpression down-regulates and enhances, respectively, the delivery of fluid-phase cargo to lysosomes, without affecting Rab5 and Rab7 recruitment to macropinosomes/endosomes. In vitro reconstitution assays show that fusion of macropinosomes/endosomes is abrogated by septin immunodepletion and function-blocking antibodies and is induced by recombinant septins in the absence of cytosol and polymerized actin. Thus, septins regulate fluid-phase cargo traffic to lysosomes by promoting macropinosome maturation and fusion with endosomes/lysosomes.

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