scholarly journals Steviol Glycosides Modulate Glucose Transport in Different Cell Types

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Benedetta Rizzo ◽  
Laura Zambonin ◽  
Cristina Angeloni ◽  
Emanuela Leoncini ◽  
Francesco Vieceli Dalla Sega ◽  
...  
Keyword(s):  
Glucose Uptake ◽  
Glucose Transport ◽  
Molecular Mechanisms ◽  
Neuroblastoma Cells ◽  
Stevia Rebaudiana ◽  
Cell Types ◽  
Akt Pathway ◽  
Steviol Glycosides ◽  
Human Neuroblastoma

Extracts fromStevia rebaudianaBertoni, a plant native to Central and South America, have been used as a sweetener since ancient times. Currently,Steviaextracts are largely used as a noncaloric high-potency biosweetener alternative to sugar, due to the growing incidence of type 2 diabetes mellitus, obesity, and metabolic disorders worldwide. Despite the large number of studies onSteviaand steviol glycosidesin vivo, little is reported concerning the cellular and molecular mechanisms underpinning the beneficial effects on human health. The effect of four commercialSteviaextracts on glucose transport activity was evaluated in HL-60 human leukaemia and in SH-SY5Y human neuroblastoma cells. The extracts were able to enhance glucose uptake in both cellular lines, as efficiently as insulin. Our data suggest that steviol glycosides could act by modulating GLUT translocation through the PI3K/Akt pathway since treatments with both insulin andSteviaextracts increased the phosphorylation of PI3K and Akt. Furthermore,Steviaextracts were able to revert the effect of the reduction of glucose uptake caused by methylglyoxal, an inhibitor of the insulin receptor/PI3K/Akt pathway. These results corroborate the hypothesis thatSteviaextracts could mimic insulin effects modulating PI3K/Akt pathway.

scholarly journals Neuron-specific activation of necroptosis signaling in multiple sclerosis cortical grey matter

2021 ◽  
Vol 141 (4) ◽  
pp. 585-604 ◽  
Author(s):  
Carmen Picon ◽  
Anusha Jayaraman ◽  
Rachel James ◽  
Catriona Beck ◽  
Patricia Gallego ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Signaling Pathway ◽  
Cortical Neurons ◽  
Grey Matter ◽  
Molecular Mechanisms ◽  
Fold Increase ◽  
Cell Types ◽  
Meningeal Inflammation ◽  
Cortical Grey Matter

AbstractSustained exposure to pro-inflammatory cytokines in the leptomeninges is thought to play a major role in the pathogenetic mechanisms leading to cortical pathology in multiple sclerosis (MS). Although the molecular mechanisms underlying neurodegeneration in the grey matter remain unclear, several lines of evidence suggest a prominent role for tumour necrosis factor (TNF). Using cortical grey matter tissue blocks from post-mortem brains from 28 secondary progressive MS subjects and ten non-neurological controls, we describe an increase in expression of multiple steps in the TNF/TNF receptor 1 signaling pathway leading to necroptosis, including the key proteins TNFR1, FADD, RIPK1, RIPK3 and MLKL. Activation of this pathway was indicated by the phosphorylation of RIPK3 and MLKL and the formation of protein oligomers characteristic of necrosomes. In contrast, caspase-8 dependent apoptotic signaling was decreased. Upregulation of necroptotic signaling occurred predominantly in macroneurons in cortical layers II–III, with little expression in other cell types. The presence of activated necroptotic proteins in neurons was increased in MS cases with prominent meningeal inflammation, with a 30-fold increase in phosphoMLKL+ neurons in layers I–III. The density of phosphoMLKL+ neurons correlated inversely with age at death, age at progression and disease duration. In vivo induction of chronically elevated TNF and INFγ levels in the CSF in a rat model via lentiviral transduction in the meninges, triggered inflammation and neurodegeneration in the underlying cortical grey matter that was associated with increased neuronal expression of TNFR1 and activated necroptotic signaling proteins. Exposure of cultured primary rat cortical neurons to TNF induced necroptosis when apoptosis was inhibited. Our data suggest that neurons in the MS cortex are dying via TNF/TNFR1 stimulated necroptosis rather than apoptosis, possibly initiated in part by chronic meningeal inflammation. Neuronal necroptosis represents a pathogenetic mechanism that is amenable to therapeutic intervention at several points in the signaling pathway.

scholarly journals Filopodyan: An open-source pipeline for the analysis of filopodia

2017 ◽  
Vol 216 (10) ◽  
pp. 3405-3422 ◽  
Author(s):  
Vasja Urbančič ◽  
Richard Butler ◽  
Benjamin Richier ◽  
Manuel Peter ◽  
Julia Mason ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Dynamic Properties ◽  
Cell Types ◽  
Molecular Heterogeneity ◽  
Interactive Editing ◽  
Motile Cells ◽  
Different Cell Types ◽  
Neuronal Growth Cones

Filopodia have important sensory and mechanical roles in motile cells. The recruitment of actin regulators, such as ENA/VASP proteins, to sites of protrusion underlies diverse molecular mechanisms of filopodia formation and extension. We developed Filopodyan (filopodia dynamics analysis) in Fiji and R to measure fluorescence in filopodia and at their tips and bases concurrently with their morphological and dynamic properties. Filopodyan supports high-throughput phenotype characterization as well as detailed interactive editing of filopodia reconstructions through an intuitive graphical user interface. Our highly customizable pipeline is widely applicable, capable of detecting filopodia in four different cell types in vitro and in vivo. We use Filopodyan to quantify the recruitment of ENA and VASP preceding filopodia formation in neuronal growth cones, and uncover a molecular heterogeneity whereby different filopodia display markedly different responses to changes in the accumulation of ENA and VASP fluorescence in their tips over time.

scholarly journals Assessment of phagocytic activity in live macrophages-tumor cells co-cultures by Confocal and Nomarski Microscopy

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Dalia Martinez-Marin ◽  
Courtney Jarvis ◽  
Thomas Nelius ◽  
Stéphanie Filleur
Keyword(s):  
Tumor Microenvironment ◽  
Tumor Cells ◽  
Phagocytic Activity ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Functional Assay ◽  
Loss Of Function ◽  
Multiple Cancer

Abstract Macrophages have been recognized as the main inflammatory component of the tumor microenvironment. Although often considered as beneficial for tumor growth and disease progression, tumor-associated macrophages have also been shown to be detrimental to the tumor depending on the tumor microenvironment. Therefore, understanding the molecular interactions between macrophages and tumor cells in relation to macrophages functional activities such as phagocytosis is critical for a better comprehension of their tumor-modulating action. Still, the characterization of these molecular mechanisms in vivo remains complicated due to the extraordinary complexity of the tumor microenvironment and the broad range of tumor-associated macrophage functions. Thus, there is an increasing demand for in vitro methodologies to study the role of cell–cell interactions in the tumor microenvironment. In the present study, we have developed live co-cultures of macrophages and human prostate tumor cells to assess the phagocytic activity of macrophages using a combination of Confocal and Nomarski Microscopy. Using this model, we have emphasized that this is a sensitive, measurable, and highly reproducible functional assay. We have also highlighted that this assay can be applied to multiple cancer cell types and used as a selection tool for a variety of different types of phagocytosis agonists. Finally, combining with other studies such as gain/loss of function or signaling studies remains possible. A better understanding of the interactions between tumor cells and macrophages may lead to the identification of new therapeutic targets against cancer.

scholarly journals Zingerone Suppresses Tumor Development through Decreasing Cyclin D1 Expression and Inducing Mitotic Arrest

2018 ◽  
Vol 19 (9) ◽  
pp. 2832 ◽  
Author(s):  
Jae-Sun Choi ◽  
Jaewook Ryu ◽  
Woom-Yee Bae ◽  
Aron Park ◽  
Seungyoon Nam ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cyclin D1 ◽  
Molecular Mechanisms ◽  
Neuroblastoma Cells ◽  
Mitotic Arrest ◽  
Therapeutic Drug ◽  
Mouse Tumor ◽  
Human Neuroblastoma Cells ◽  
Human Neuroblastoma ◽  
Mitotic Cells

Cancer cells undergo uncontrolled proliferation resulting from aberrant activity of various cell-cycle proteins. Therefore, despite recent advances in intensive chemotherapy, it is difficult to cure cancer completely. Recently, cell-cycle regulators became attractive targets in cancer therapy. Zingerone, a phenolic compound isolated from ginger, is a nontoxic and inexpensive compound with varied pharmacological activities. In this study, the therapeutic effect of zingerone as an anti-mitotic agent in human neuroblastoma cells was investigated. Following treatment of BE(2)-M17 cells with zingerone, we performed a 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay and colony-formation assay to evaluate cellular proliferation, in addition to immunofluorescence cytochemistry and flow cytometry to examine the mitotic cells. The association of gene expression with tumor stage and survival was analyzed. Furthermore, to examine the anti-cancer effect of zingerone, we applied a BALB/c mouse-tumor model using a BALB/c-derived adenocarcinoma cell line. In human neuroblastoma cells, zingerone inhibited cellular viability and survival. Moreover, the number of mitotic cells, particularly those in prometaphase, increased in zingerone-treated neuroblastoma cells. Regarding specific molecular mechanisms, zingerone decreased cyclin D1 expression and induced the cleavage of caspase-3 and poly (ADP-ribose) polymerase 1 (PARP-1). The decrease in cyclin D1 and increase in histone H3 phosphorylated (p)-Ser10 were confirmed by immunohistochemistry in tumor tissues administered with zingerone. These results suggest that zingerone induces mitotic arrest followed by inhibition of growth of neuroblastoma cells. Collectively, zingerone may be a potential therapeutic drug for human cancers, including neuroblastoma.

The expression, lamin-dependent localization and RNAi depletion phenotype for emerin inC. elegans

2002 ◽  
Vol 115 (5) ◽  
pp. 923-929 ◽  
Author(s):  
Yosef Gruenbaum ◽  
Kenneth K. Lee ◽  
Jun Liu ◽  
Merav Cohen ◽  
Katherine L. Wilson
Keyword(s):  
Nuclear Envelope ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Growth Conditions ◽  
Rnai Phenotype ◽  
Lamin B ◽  
C Elegans ◽  
Nuclear Lamins ◽  
First Time

Emerin belongs to the LEM-domain family of nuclear membrane proteins, which are conserved in metazoans from C. elegans to humans. Loss of emerin in humans causes the X-linked form of Emery-Dreifuss muscular dystrophy(EDMD), but the disease mechanism is not understood. We have begun to address the function of emerin in C. elegans, a genetically tractable nematode. The emerin gene (emr-1) is conserved in C. elegans. We detect Ce-emerin protein in the nuclear envelopes of all cell types except sperm, and find that Ce-emerin co-immunoprecipitates with Ce-lamin from embryo lysates. We show for the first time in any organism that nuclear lamins are essential for the nuclear envelope localization of emerin during early development. We further show that four other types of nuclear envelope proteins, including fellow LEM-domain protein Ce-MAN1, as well as Ce-lamin, UNC-84 and nucleoporins do not depend on Ce-emerin for their localization. This result suggests that emerin is not essential to organize or localize the only lamin (B-type) expressed in C. elegans. We also analyzed the RNAi phenotype resulting from the loss of emerin function in C. elegans under laboratory growth conditions, and found no detectable phenotype throughout development. We propose that C. elegans is an appropriate system in which to study the molecular mechanisms of emerin function in vivo.

Advances and Challenges in Kidney Organoids

2021 ◽  
Vol 16 ◽  
Author(s):  
Vikram Sabapathy ◽  
Gabrielle Costlow ◽  
Rajkumar Venkatadri ◽  
Murat Dogan ◽  
Sanjay Kumar ◽  
...  
Keyword(s):  
Cell Fate ◽  
Pluripotent Stem Cells ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Complex Structures ◽  
Cell Culture Systems ◽  
Epigenetic Signatures ◽  
Kidney Organoids

: The advent of organoids has renewed researcher's interest in in vitro cell culture systems. A wide variety of protocols, primarily utilizing pluripotent stem cells, are under development to improve organoid generation to mimic organ development. The complexity of organoids generated is greatly influenced based on the method used. Understanding the process of kidney organoid formation gives developmental insights into how renal cells form, mature, and interact with the adjacent cells to form specific spatiotemporal structural patterns. This knowledge can bridge the gaps in understanding in vivo renal developmental processes. Evaluating genetic and epigenetic signatures in specialized cell types can help interpret the molecular mechanisms governing cell fate. In addition, development in single-cell RNA sequencing and 3D bioprinting and microfluidic technologies has led to better identification and understanding of a variety of cell types during differentiation and designing of complex structures to mimic the conditions in vivo. While several reviews have highlighted the application of kidney organoids, there is no comprehensive review of various methodologies specifically focusing on the kidney organoids. This review summarizes the updated differentiation methodologies, applications, and challenges associated with kidney organoids. Here we have comprehensively collated all the different variables influencing the organoid generation.

Cytokine-induced changes in chromatin structure and in vivo footprints in the inducible NOS promoter

2001 ◽  
Vol 280 (3) ◽  
pp. L390-L399 ◽  
Author(s):  
Jane K. Mellott ◽  
Harry S. Nick ◽  
Michael F. Waters ◽  
Timothy R. Billiar ◽  
David A. Geller ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Protein Interactions ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Specific Pattern ◽  
Mrna Levels ◽  
Inos Gene ◽  
In Vivo Footprinting ◽  
Induced Changes

Transcription of the human inducible nitric oxide synthase ( iNOS) gene is regulated by inflammatory cytokines in a tissue-specific manner. To determine whether differences in cytokine-induced mRNA levels between pulmonary epithelial cells (A549) and hepatic biliary epithelial cells (AKN-1) result from different protein or DNA regulatory mechanisms, we identified cytokine-induced changes in DNase I-hypersensitive (HS) sites in 13 kb of the iNOS 5′-flanking region. Data showed both constitutive and inducible HS sites in an overlapping yet cell type-specific pattern. Using in vivo footprinting and ligation-mediated PCR to detect potential DNA or protein interactions, we examined one promoter region near −5 kb containing both constitutive and cytokine-induced HS sites. In both cell types, three in vivo footprints were present in both control and cytokine-treated cells, and each mapped within a constitutive HS site. The remaining footprint appeared only in response to cytokine treatment and mapped to an inducible HS site. These studies, performed on chromatin in situ, identify a portion of the molecular mechanisms regulating transcription of the human iNOS gene in both lung- and liver-derived epithelial cells.

scholarly journals Tumor quiescence: elevating SOX2 in diverse tumor cell types downregulates a broad spectrum of the cell cycle machinery and inhibits tumor growth

BMC Cancer ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ethan P. Metz ◽  
Erin L. Wuebben ◽  
Phillip J. Wilder ◽  
Jesse L. Cox ◽  
Kaustubh Datta ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Tumor Growth ◽  
Tumor Cell ◽  
Tumor Cells ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Cell Cycle Machinery

Abstract Background Quiescent tumor cells pose a major clinical challenge due to their ability to resist conventional chemotherapies and to drive tumor recurrence. Understanding the molecular mechanisms that promote quiescence of tumor cells could help identify therapies to eliminate these cells. Significantly, recent studies have determined that the function of SOX2 in cancer cells is highly dose dependent. Specifically, SOX2 levels in tumor cells are optimized to promote tumor growth: knocking down or elevating SOX2 inhibits proliferation. Furthermore, recent studies have shown that quiescent tumor cells express higher levels of SOX2 compared to adjacent proliferating cells. Currently, the mechanisms through which elevated levels of SOX2 restrict tumor cell proliferation have not been characterized. Methods To understand how elevated levels of SOX2 restrict the proliferation of tumor cells, we engineered diverse types of tumor cells for inducible overexpression of SOX2. Using these cells, we examined the effects of elevating SOX2 on their proliferation, both in vitro and in vivo. In addition, we examined how elevating SOX2 influences their expression of cyclins, cyclin-dependent kinases (CDKs), and p27Kip1. Results Elevating SOX2 in diverse tumor cell types led to growth inhibition in vitro. Significantly, elevating SOX2 in vivo in pancreatic ductal adenocarcinoma, medulloblastoma, and prostate cancer cells induced a reversible state of tumor growth arrest. In all three tumor types, elevation of SOX2 in vivo quickly halted tumor growth. Remarkably, tumor growth resumed rapidly when SOX2 returned to endogenous levels. We also determined that elevation of SOX2 in six tumor cell lines decreased the levels of cyclins and CDKs that control each phase of the cell cycle, while upregulating p27Kip1. Conclusions Our findings indicate that elevating SOX2 above endogenous levels in a diverse set of tumor cell types leads to growth inhibition both in vitro and in vivo. Moreover, our findings indicate that SOX2 can function as a master regulator by controlling the expression of a broad spectrum of cell cycle machinery. Importantly, our SOX2-inducible tumor studies provide a novel model system for investigating the molecular mechanisms by which elevated levels of SOX2 restrict cell proliferation and tumor growth.

scholarly journals The Rise of Retinal Organoids for Vision Research

2020 ◽  
Vol 21 (22) ◽  
pp. 8484 ◽  
Author(s):  
Kritika Sharma ◽  
Tim U. Krohne ◽  
Volker Busskamp
Keyword(s):  
Molecular Mechanisms ◽  
Cell Types ◽  
Therapeutic Interventions ◽  
Retinal Cell ◽  
Retinal Diseases ◽  
Organ Systems ◽  
Cell Sources ◽  
Retinal Degenerative Diseases

Retinal degenerative diseases lead to irreversible blindness. Decades of research into the cellular and molecular mechanisms of retinal diseases, using either animal models or human cell-derived 2D systems, facilitated the development of several therapeutic interventions. Recently, human stem cell-derived 3D retinal organoids have been developed. These self-organizing 3D organ systems have shown to recapitulate the in vivo human retinogenesis resulting in morphological and functionally similar retinal cell types in vitro. In less than a decade, retinal organoids have assisted in modeling several retinal diseases that were rather difficult to mimic in rodent models. Retinal organoids are also considered as a photoreceptor source for cell transplantation therapies to counteract blindness. Here, we highlight the development and field’s improvements of retinal organoids and discuss their application aspects as human disease models, pharmaceutical testbeds, and cell sources for transplantations.

Hepatobiliary Differentiation: Principles from Embryonic Liver Development

2020 ◽  
Vol 40 (04) ◽  
pp. 365-372
Author(s):  
Scott H. Freeburg ◽  
Wolfram Goessling
Keyword(s):  
Molecular Mechanisms ◽  
Alagille Syndrome ◽  
Cell Types ◽  
Extrinsic Cues ◽  
Hepatic Portal Vein ◽  
Hepatic Portal ◽  
Transcription Factor Expression ◽  
In Vitro Data

AbstractHepatocytes and biliary epithelial cells (BECs), the two endodermal cell types of the liver, originate from progenitor cells called hepatoblasts. Based principally on in vitro data, hepatoblasts are thought to be bipotent stem cells with the potential to produce both hepatocytes and BECs. However, robust in vivo evidence for this model has only recently emerged. We examine the molecular mechanisms that stimulate hepatoblast differentiation into hepatocytes or BECs. In the absence of extrinsic cues, the default fate of hepatoblasts is hepatocyte differentiation. Inductive cues from the hepatic portal vein, however, initiate transcription factor expression in hepatoblasts, driving biliary specification. Defining the mechanisms of hepatobiliary differentiation provides important insights into congenital disorders, such as Alagille syndrome, and may help to better characterize the poorly understood hepatic lineage relationships observed during regeneration from liver injury.

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