scholarly journals Zn2+ influx activates ERK and Akt signaling pathways

2021 ◽  
Vol 118 (11) ◽  
pp. e2015786118
Author(s):  
Kelsie J. Anson ◽  
Giulia A. Corbet ◽  
Amy E. Palmer
Keyword(s):  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Single Cells ◽  
Cell Types ◽  
Cell Physiology ◽  
Kinase Signaling ◽  
Experimental Conditions ◽  
Kinase Activation ◽  
Fluorescent Biosensors ◽  
Stress Dependent

Zinc (Zn2+) is an essential metal in biology, and its bioavailability is highly regulated. Many cell types exhibit fluctuations in Zn2+ that appear to play an important role in cellular function. However, the detailed molecular mechanisms by which Zn2+ dynamics influence cell physiology remain enigmatic. Here, we use a combination of fluorescent biosensors and cell perturbations to define how changes in intracellular Zn2+ impact kinase signaling pathways. By simultaneously monitoring Zn2+ dynamics and kinase activity in individual cells, we quantify changes in labile Zn2+ and directly correlate changes in Zn2+ with ERK and Akt activity. Under our experimental conditions, Zn2+ fluctuations are not toxic and do not activate stress-dependent kinase signaling. We demonstrate that while Zn2+ can nonspecifically inhibit phosphatases leading to sustained kinase activation, ERK and Akt are predominantly activated via upstream signaling and through a common node via Ras. We provide a framework for quantification of Zn2+ fluctuations and correlate these fluctuations with signaling events in single cells to shed light on the role that Zn2+ dynamics play in healthy cell signaling.

scholarly journals Zn2+ influx activates ERK and Akt signaling pathways through a common mechanism

2020 ◽  
Author(s):  
Kelsie J. Anson ◽  
Giulia A. Corbet ◽  
Amy E. Palmer
Keyword(s):  
Cell Signaling ◽  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Single Cells ◽  
The Body ◽  
Common Mechanism ◽  
Cell Physiology ◽  
Kinase Signaling ◽  
Stress Dependent ◽  
Shed Light

AbstractZinc (Zn2+) is an essential metal in biology and its bioavailability is highly regulated. Many cell types exhibit fluctuations in Zn2+ that appear to play an important role in cellular function. However, the detailed molecular mechanisms by which Zn2+ dynamics influence cell physiology remain enigmatic. Here, we use a combination of fluorescent biosensors and cell perturbations to define how changes in intracellular Zn2+ impact kinase signaling pathways. By simultaneously monitoring Zn2+ dynamics and kinase activity in individual cells, we quantify changes in labile Zn2+ and directly correlate changes in Zn2+ with ERK and Akt activity. Under our experimental conditions, Zn2+ fluctuations are not toxic and do not activate stress-dependent kinase signaling. We demonstrate that while Zn2+ can non-specifically inhibit phosphatases leading to sustained kinase activation, ERK and Akt are predominantly activated via upstream signaling, and through a common node via Ras. We provide a framework for quantification of Zn2+ fluctuations and correlate these fluctuations with signaling events in single cells to shed light on the role that Zn2+ dynamics play in healthy cell signaling.Significance StatementWhile zinc (Zn2+) is a vital ion for cell function and human health, little is known about the role it plays in regulating cell signaling. Here, we use fluorescent tools to study the interaction between Zn2+ and cell signaling pathways that play a role in cell growth and proliferation. Importantly, we use small, non-toxic Zn2+concentrations to ensure that our Zn2+ changes are closer to what cells would experience in the body and not stress-inducing. We also demonstrate that these signaling changes are driven by Ras activation, which contradicts one of the major hypotheses in the field. Our sensors shed light on how cells respond to a very important micronutrient in real time.

scholarly journals Tim-3 enhances FcεRI-proximal signaling to modulate mast cell activation

2015 ◽  
Vol 212 (13) ◽  
pp. 2289-2304 ◽  
Author(s):  
Binh L. Phong ◽  
Lyndsay Avery ◽  
Tina L. Sumpter ◽  
Jacob V. Gorman ◽  
Simon C. Watkins ◽  
...  
Keyword(s):  
T Cells ◽  
Mast Cell ◽  
Signaling Pathways ◽  
Cell Activation ◽  
Molecular Mechanisms ◽  
Late Phase ◽  
Cell Types ◽  
Mast Cell Activation ◽  
Positive Role ◽  
Ample Evidence

T cell (or transmembrane) immunoglobulin and mucin domain protein 3 (Tim-3) has attracted significant attention as a novel immune checkpoint receptor (ICR) on chronically stimulated, often dysfunctional, T cells. Antibodies to Tim-3 can enhance antiviral and antitumor immune responses. Tim-3 is also constitutively expressed by mast cells, NK cells and specific subsets of macrophages and dendritic cells. There is ample evidence for a positive role for Tim-3 in these latter cell types, which is at odds with the model of Tim-3 as an inhibitory molecule on T cells. At this point, little is known about the molecular mechanisms by which Tim-3 regulates the function of T cells or other cell types. We have focused on defining the effects of Tim-3 ligation on mast cell activation, as these cells constitutively express Tim-3 and are activated through an ITAM-containing receptor for IgE (FcεRI), using signaling pathways analogous to those in T cells. Using a variety of gain- and loss-of-function approaches, we find that Tim-3 acts at a receptor-proximal point to enhance Lyn kinase-dependent signaling pathways that modulate both immediate-phase degranulation and late-phase cytokine production downstream of FcεRI ligation.

MO262THE SINGLE-CELL TRANSCRIPTOMICS OF HUMAN IGA NEPHROPATHY

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Yong Zhong ◽  
Xiangcheng Xiao
Keyword(s):  
Gene Expression ◽  
Single Cell ◽  
Signaling Pathways ◽  
Iga Nephropathy ◽  
Molecular Mechanisms ◽  
Mesangial Cells ◽  
Therapeutic Targets ◽  
Cell Types ◽  
Receptor Crosstalk ◽  
Overt Proteinuria

Abstract Background and Aims The exact molecular mechanisms underlying IgA nephropathy (IgAN) remains incompletely defined. Therefore, it is necessary to further elucidate the mechanism of IgA nephropathy and find novel therapeutic targets. Method Single-cell RNA sequencing (scRNA-seq) was applied to kidney biopsies from 4 IgAN and 1 control subjects to define the transcriptomic landscape at the single-cell resolution. Unsupervised clustering analysis of kidney specimens was used to identify distinct cell clusters. Differentially expressed genes and potential signaling pathways involved in IgAN were also identified. Results Our analysis identified 14 cell subsets in kidney biopsies from IgAN patients, and analyzed changing gene expression in distinct renal cell types. We found increased mesangial expression of several novel genes including MALAT1, GADD45B, SOX4 and EDIL3, which were related to proliferation and matrix accumulation and have not been reported in IgAN previously. The overexpressed genes in tubule cells of IgAN were mainly enriched in inflammatory pathways including TNF signaling, IL-17 signaling and NOD-like receptor signaling. Moreover, the receptor-ligand crosstalk analysis revealed potential interactions between mesangial cells and other cells in IgAN. Specifically, IgAN with overt proteinuria displayed elevated genes participating in several signaling pathways which may be involved in pathogenesis of progression of IgAN. Conclusion The comprehensive analysis of kidney biopsy specimen demonstrated different gene expression profile, potential pathologic ligand-receptor crosstalk, signaling pathways in human IgAN. These results offer new insight into pathogenesis and identify new therapeutic targets for patients with IgA nephropathy.

scholarly journals Nimodipine-Dependent Protection of Schwann Cells, Astrocytes and Neuronal Cells from Osmotic, Oxidative and Heat Stress Is Associated with the Activation of AKT and CREB

2019 ◽  
Vol 20 (18) ◽  
pp. 4578 ◽  
Author(s):  
Sandra Leisz ◽  
Sebastian Simmermacher ◽  
Julian Prell ◽  
Christian Strauss ◽  
Christian Scheller
Keyword(s):  
Heat Stress ◽  
Schwann Cells ◽  
Molecular Mechanisms ◽  
Neuroprotective Effect ◽  
Neuronal Cells ◽  
Cell Types ◽  
Stress Conditions ◽  
Cell Culture Supernatant ◽  
Neuroprotective Effects ◽  
Stress Dependent

Clinical and experimental data assumed a neuroprotective effect of the calcium channel blocker nimodipine. However, it has not been proven which neuronal or glial cell types are affected by nimodipine and which mechanisms underlie these neuroprotective effects. Therefore, the aim of this study was to investigate the influence of nimodipine treatment on the in vitro neurotoxicity of different cell types in various stress models and to identify the associated molecular mechanisms. Therefore, cell lines from Schwann cells, neuronal cells and astrocytes were pretreated for 24 h with nimodipine and incubated under stress conditions such as osmotic, oxidative and heat stress. The cytotoxicity was measured via the lactate dehydrogenase (LDH) activity of cell culture supernatant. As a result, the nimodipine treatment led to a statistically significantly reduced cytotoxicity in Schwann cells and neurons during osmotic (p ≤ 0.01), oxidative (p ≤ 0.001) and heat stress (p ≤ 0.05), when compared to the vehicle. The cytotoxicity of astrocytes was nimodipine-dependently reduced during osmotic (p ≤ 0.01), oxidative (p ≤ 0.001) and heat stress (not significant). Moreover, a decreased caspase activity as well as an increased proteinkinase B (AKT) and cyclic adenosine monophosphate response element-binding protein (CREB) phosphorylation could be observed after the nimodipine treatment under different stress conditions. These results demonstrate a cell type-independent neuroprotective effect of the prophylactic nimodipine treatment, which is associated with the prevention of stress-dependent apoptosis through the activation of CREB and AKT signaling pathways and the reduction of caspase 3 activity.

scholarly journals Single-Cell RNA Sequencing to Disentangle the Blood System

2021 ◽  
Vol 41 (3) ◽  
pp. 1012-1018
Author(s):  
Jean Acosta ◽  
Daniel Ssozi ◽  
Peter van Galen
Keyword(s):  
Blood Cell ◽  
Single Cell ◽  
Rna Sequencing ◽  
Molecular Mechanisms ◽  
Single Cells ◽  
Cell Types ◽  
Blood System ◽  
Differentiated Cells ◽  
Tissue Organization ◽  
Single Cell Rna Sequencing

The blood system is often represented as a tree-like structure with stem cells that give rise to mature blood cell types through a series of demarcated steps. Although this representation has served as a model of hierarchical tissue organization for decades, single-cell technologies are shedding new light on the abundance of cell type intermediates and the molecular mechanisms that ensure balanced replenishment of differentiated cells. In this Brief Review, we exemplify new insights into blood cell differentiation generated by single-cell RNA sequencing, summarize considerations for the application of this technology, and highlight innovations that are leading the way to understand hematopoiesis at the resolution of single cells. Graphic Abstract: A graphic abstract is available for this article.

scholarly journals Predicting global dynamics of spatial microbial communities from local interaction rules

2020 ◽  
Author(s):  
Simon van Vliet ◽  
Christoph Hauert ◽  
Martin Ackermann ◽  
Alma Dal Co
Keyword(s):  
Growth Rate ◽  
Microbial Communities ◽  
Molecular Mechanisms ◽  
Single Cells ◽  
Cell Types ◽  
Cell Interactions ◽  
Community Level ◽  
Global Dynamics ◽  
Mathematical Framework ◽  
Cell Cell

AbstractInteractions between cells drive biological processes across all of life, from microbes in the environment to cells in multicellular organisms. Interactions often arise in spatially structured settings, where cells mostly interact with their neighbors. A central question is how the properties of biological systems emerge from local interactions. This question is very relevant in the context of microbial communities, such as biofilms, where cells live close by in space and are connected via a dense network of biochemical interactions. To understand and control the functioning of these communities, it is essential to uncover how community-level properties, such as the community composition, spatial arrangement, and growth rate, arise from these interactions. Here, we develop a mathematical framework that can predict community-level properties from the molecular mechanisms underlying the cell-cell interactions for systems consisting of two cell types. Our predictions match quantitative measurements from an experimental cross-feeding community. For these cross-feeding communities, the community growth rate is reduced when cells interact only with few neighbors; as a result, some communities can co-exist in a well-mixed system, but not in a spatial one. In general, our framework shows that key molecular parameters underlying the cell-cell interactions (e.g. the uptake and leakage rates of molecules) determine community level properties. Our framework can be extended to a variety of systems of two interacting cell types, within and beyond the microbial world, and contributes to our understanding of how biological functions arise from interactions between single cells.

scholarly journals Protection of Tong-Sai-Mai Decoction against Apoptosis Induced by H2O2in PC12 Cells: Mechanisms via Bcl-2-Mitochondria-ROS-INOS Pathway

2014 ◽  
Vol 2014 ◽  
pp. 1-18 ◽  
Author(s):  
Maxwell Kim Kit Lee ◽  
Yin Lu ◽  
Liu-qing Di ◽  
Hui-qin Xu
Keyword(s):  
Oxidative Stress ◽  
Pc12 Cells ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
In Vivo Studies ◽  
Marker Genes ◽  
Mitochondria Membrane Potential ◽  
Stress Dependent

Tong-Sai-Mai decoction (TSM) is a Chinese materia medica polyherbal formulation that has been applied in treating brain ischemia for hundreds of years. Because it could repress the oxidative stress in in vivo studies, now we focus on the in vitro studies to investigate the mechanism by targeting the oxidative stress dependent signaling. The relation between the neurogenesis and the reactive oxygen species (ROS) production remains largely unexamined. PC12 cells are excitable cell types widely used as in vitro model for neuronal cells. Most marker genes that are related to neurotoxicity, apoptosis, and cell cycles are expressed at high levels in these cells. The aim of the present study is to explore the cytoprotection of TSM against hydrogen peroxide- (H2O2-) induced apoptosis and the molecular mechanisms underlying PC12 cells. Our findings revealed that TSM cotreatment with H2O2restores the expression of bcl-2, inducible nitric oxide synthase (INOS), and mitochondria membrane potential. Meanwhile, it reduces intracellular [Ca2+] concentration, lactate dehydrogenase (LDH) release, and the expression of caspase-3 and bax. The results of the present study suggested that the cytoprotective effects of the TSM might be mediated, at least in part, by the bcl-2-mitochondria-ROS-INOS pathway. Due to its nontoxic characteristics, TSM could be further developed to treat the neurodegenerative diseases which are closely associated with the oxidative stress.

scholarly journals Lipid Mediators Regulate Pulmonary Fibrosis: Potential Mechanisms and Signaling Pathways

2020 ◽  
Vol 21 (12) ◽  
pp. 4257 ◽  
Author(s):  
Vidyani Suryadevara ◽  
Ramaswamy Ramchandran ◽  
David W. Kamp ◽  
Viswanathan Natarajan
Keyword(s):  
Pulmonary Fibrosis ◽  
Signaling Pathways ◽  
Lung Fibrosis ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Lipid Mediators ◽  
Alveolar Epithelial Cells ◽  
Sphingolipid Metabolism ◽  
Unknown Etiology ◽  
Preclinical Animal Models

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease of unknown etiology characterized by distorted distal lung architecture, inflammation, and fibrosis. The molecular mechanisms involved in the pathophysiology of IPF are incompletely defined. Several lung cell types including alveolar epithelial cells, fibroblasts, monocyte-derived macrophages, and endothelial cells have been implicated in the development and progression of fibrosis. Regardless of the cell types involved, changes in gene expression, disrupted glycolysis, and mitochondrial oxidation, dysregulated protein folding, and altered phospholipid and sphingolipid metabolism result in activation of myofibroblast, deposition of extracellular matrix proteins, remodeling of lung architecture and fibrosis. Lipid mediators derived from phospholipids, sphingolipids, and polyunsaturated fatty acids play an important role in the pathogenesis of pulmonary fibrosis and have been described to exhibit pro- and anti-fibrotic effects in IPF and in preclinical animal models of lung fibrosis. This review describes the current understanding of the role and signaling pathways of prostanoids, lysophospholipids, and sphingolipids and their metabolizing enzymes in the development of lung fibrosis. Further, several of the lipid mediators and enzymes involved in their metabolism are therapeutic targets for drug development to treat IPF.

scholarly journals Morphometric Analysis of Rat Prostate Development: Roles of MEK/ERK and Rho Signaling Pathways in Prostatic Morphogenesis

Biomolecules ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1829
Author(s):  
Wen-Yang Hu ◽  
Parivash Afradiasbagharani ◽  
Ranli Lu ◽  
Lifeng Liu ◽  
Lynn A. Birch ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Signaling Pathways ◽  
Light Chain ◽  
Myosin Light Chain ◽  
Molecular Mechanisms ◽  
Rho Kinase ◽  
Branching Morphogenesis ◽  
Kinase Signaling ◽  
Prostate Cell ◽  
Prostate Development

The molecular mechanisms underlying prostate development can provide clues for prostate cancer research. It has been demonstrated that MEK/ERK signaling downstream of androgen-targeted FGF10 signaling directly induces prostatic branching during development, while Rho/Rho-kinase can regulate prostate cell proliferation. MEK/ERK and Rho/Rho kinase regulate myosin light chain kinase (MLCK), and MLCK regulates myosin light chain phosphorylation (MLC-P), which is critical for cell fate, including cell proliferation, differentiation, and apoptosis. However, the roles and crosstalk of the MEK/ERK and Rho/Rho kinase signaling pathways in prostatic morphogenesis have not been examined. In the present study, we used numerical and image analysis to characterize lobe-specific rat prostatic branching during postnatal organ culture and investigated the roles of FGF10-MEK/ERK and Rho/Rho kinase signaling pathways in prostatic morphogenesis. Prostates exhibited distinctive lobe-specific growth and branching patterns in the ventral (VP) and lateral (LP) lobes, while exogenous FGF10 treatment shifted LP branching towards a VP branching pattern. Treatment with inhibitors of MEK1/2, Rho, Rho kinase, or MLCK significantly inhibited VP growth and blocked branching morphogenesis, further supporting critical roles for MEK/ERK and Rho/Rho kinase signaling pathways in prostatic growth and branching during development. We propose that MLCK-regulated MLC-P may be a central downstream target of both signaling pathways in regulating prostate morphogenesis.

scholarly journals ID: 1039 The antidepressant fluoxetine inhibits adenylate cyclase stimulation by FSH or Forskolin in the COV434 human ovarian granulosa tumor cell line

2017 ◽  
Vol 4 (S) ◽  
pp. 117
Author(s):  
Thi Mong Diep Nguyen ◽  
Danièle Klett ◽  
Minh Thu Vo ◽  
Yves Combarnous
Keyword(s):  
Signaling Pathways ◽  
Granulosa Cells ◽  
Molecular Mechanisms ◽  
Follicular Development ◽  
Tumor Cell Line ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Cell Types ◽  
Intracellular Camp ◽  
Human Granulosa Cells

Fluoxetine (Prozac), a selective Serotonin Reuptake Inhibitor antidepressant, exhibits other mechanisms of action in various cell types and has been shown to induce cell death in cancer cells, paving the way for its potential use in cancer therapy. The ovary is a complex endocrine organ responsible for steroidogenesis and folliculogenesis, and human granulosa cells are essential for scientific research to improve the understanding of these two processes. However, little is known about fundamental signaling pathways in human granulosa cells. In this study, we investigated the dynamics of intracellular cyclic adenosine monophosphate AMP, a conserved signaling messenger that can regulate virtually every physiological process. We show that incubating COV434 human ovarian granulosa cells with fluoxetine induces a decrease in intracellular cAMP response to Follicle-stimulating hormone (FSH) and forskolin (FSK). In order to study the intracellular cAMP kinetic responses of COV434 cells to FSH or FSK, we used COV434 cells transiently expressing a chimeric cAMP-responsive luciferase so that real-time variations of intracellular cAMP concentration could be monitored, by using oxiluciferin luminescence produced from catalyzed luciferin oxidation. Our data show that fluoxetine induces an increase in the extracellular Ca2+ entry and reduces ATP concentration as well as cell viability. Targeting these signaling pathways with fluoxetine could permit to get better knowledge in the molecular mechanisms involved in ovarian follicular development

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