Activation of signalling pathways during hepatocyte isolation: relevance to toxicology in vitro

2004 ◽  
Vol 18 (2) ◽  
pp. 187-193 ◽  
Author(s):  
Alan J Paine ◽  
Evangelos Andreakos
Keyword(s):  
Signalling Pathways ◽  
Hepatocyte Isolation

scholarly journals An ARF GTPase module promoting invasion and metastasis through regulating phosphoinositide metabolism

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Marisa Nacke ◽  
Emma Sandilands ◽  
Konstantina Nikolatou ◽  
Álvaro Román-Fernández ◽  
Susan Mason ◽  
...  
Keyword(s):  
Metastatic Cancer ◽  
Cellular Responses ◽  
Signalling Pathways ◽  
External Signal ◽  
Phosphoinositide Metabolism ◽  
Invasion And Metastasis ◽  
3 Dimensional

AbstractThe signalling pathways underpinning cell growth and invasion use overlapping components, yet how mutually exclusive cellular responses occur is unclear. Here, we report development of 3-Dimensional culture analyses to separately quantify growth and invasion. We identify that alternate variants of IQSEC1, an ARF GTPase Exchange Factor, act as switches to promote invasion over growth by controlling phosphoinositide metabolism. All IQSEC1 variants activate ARF5- and ARF6-dependent PIP5-kinase to promote PI(3,4,5)P3-AKT signalling and growth. In contrast, select pro-invasive IQSEC1 variants promote PI(3,4,5)P3 production to form invasion-driving protrusions. Inhibition of IQSEC1 attenuates invasion in vitro and metastasis in vivo. Induction of pro-invasive IQSEC1 variants and elevated IQSEC1 expression occurs in a number of tumour types and is associated with higher-grade metastatic cancer, activation of PI(3,4,5)P3 signalling, and predicts long-term poor outcome across multiple cancers. IQSEC1-regulated phosphoinositide metabolism therefore is a switch to induce invasion over growth in response to the same external signal. Targeting IQSEC1 as the central regulator of this switch may represent a therapeutic vulnerability to stop metastasis.

A novel vasculo-angiogenic effect of cilostazol mediated by cross-talk between multiple signalling pathways including the ERK/p38 MAPK signalling transduction cascade

2012 ◽  
Vol 123 (3) ◽  
pp. 147-159 ◽  
Author(s):  
Ting-Hsing Chao ◽  
Shih-Ya Tseng ◽  
Yi-Heng Li ◽  
Ping-Yen Liu ◽  
Chung-Lung Cho ◽  
...  
Keyword(s):  
Protein Kinase ◽  
P38 Mapk ◽  
Umbilical Vein ◽  
Tube Formation ◽  
Mitogen Activated Protein Kinase ◽  
Signalling Pathways ◽  
No Production ◽  
Angiogenic Effect

Cilostazol is an anti-platelet agent with vasodilatory activity that acts by increasing intracellular concentrations of cAMP. Recent reports have suggested that cilostazol may promote angiogenesis. In the present study, we have investigated the effect of cilostazol in promoting angiogenesis and vasculogenesis in a hindlimb ischaemia model and have also examined its potential mechanism of action in vitro and in vivo. We found that cilostazol treatment significantly increased colony formation by human early EPCs (endothelial progenitor cells) through a mechanism involving the activation of cAMP/PKA (protein kinase A), PI3K (phosphoinositide 3-kinase)/Akt/eNOS (endothelial NO synthase) and ERK (extracellular-signal-regulated kinase)/p38 MAPK (mitogen-activated protein kinase) signalling pathways. Cilostazol also enhanced proliferation, chemotaxis, NO production and vascular tube formation in HUVECs (human umbilical vein endothelial cells) through activation of multiple signalling pathways downstream of PI3K/Akt/eNOS. Cilostazol up-regulated VEGF (vascular endothelial growth factor)-A165 expression and secretion of VEGF-A in HUVECs through activation of the PI3K/Akt/eNOS pathway. In a mouse hindlimb ischaemia model, recovery of blood flow ratio (ipsilateral/contralateral) 14 days after surgery was significantly improved in cilostazol-treated mice (10 mg/kg of body weight) compared with vehicle-treated controls (0.63±0.07 and 0.43±0.05 respectively, P<0.05). Circulating CD34+ cells were also increased in cilostazol-treated mice (3614±670 compared with 2151±608 cells/ml, P<0.05). Expression of VEGF and phosphorylation of PI3K/Akt/eNOS and ERK/p38 MAPK in ischaemic muscles were significantly enhanced by cilostazol. Our data suggest that cilostazol produces a vasculo-angiogenic effect by up-regulating a broad signalling network that includes the ERK/p38 MAPK, VEGF-A165, PI3K/Akt/eNOS and cAMP/PKA pathways.

scholarly journals Persistent Newcastle disease virus infection in bladder cancer cells is associated with putative pro-survival and anti-viral transcriptomic changes

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lee-Chin Chan ◽  
Jeevanathan Kalyanasundram ◽  
Sze-Wei Leong ◽  
Mas Jaffri Masarudin ◽  
Abhi Veerakumarasivam ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Newcastle Disease Virus ◽  
Cancer Cells ◽  
Disease Virus ◽  
Newcastle Disease ◽  
Persistent Infection ◽  
Signalling Pathways ◽  
Bladder Cancer Cells ◽  
Transcriptomic Changes

Abstract Background Newcastle disease virus (NDV) is an oncolytic virus with excellent selectivity against cancer cells, both in vitro and in vivo. Unfortunately, prolonged in vitro NDV infection results in the development of persistent infection in the cancer cells which are then able to resist NDV-mediated oncolysis. However, the mechanism of persistency of infection remains poorly understood. Methods In this study, we established persistently NDV-infected EJ28 bladder cancer cells, designated as EJ28P. Global transcriptomic analysis was subsequently carried out by microarray analysis. Differentially expressed genes (DEGs) between EJ28 and EJ28P cells identified by the edgeR program were further analysed by Gene Set Enrichment Analysis (GSEA) and Ingenuity Pathway Analysis (IPA) analyses. In addition, the microarray data were validated by RT-qPCR. Results Persistently NDV-infected EJ28 bladder cancer cells were successfully established and confirmed by flow cytometry. Microarray analysis identified a total of 368 genes as differentially expressed in EJ28P cells when compared to the non-infected EJ28 cells. GSEA revealed that the Wnt/β-catenin and KRAS signalling pathways were upregulated while the TGF-β signalling pathway was downregulated. Findings from this study suggest that the upregulation of genes that are associated with cell growth, pro-survival, and anti-apoptosis may explain the survivability of EJ28P cells and the development of persistent infection of NDV. Conclusions This study provides insights into the transcriptomic changes that occur and the specific signalling pathways that are potentially involved in the development and maintenance of NDV persistency of infection in bladder cancer cells. These findings warrant further investigation and is crucial towards the development of effective NDV oncolytic therapy against cancer.

scholarly journals Network Pharmacology-Based Study of the Underlying Mechanisms of Huangqi Sijunzi Decoction for Alzheimer’s Disease

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Wei Zhang ◽  
Mingti Lv ◽  
Yating Shi ◽  
Yonghui Mu ◽  
Zhaoyang Yao ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Neuroprotective Effect ◽  
Signalling Pathway ◽  
Signalling Pathways ◽  
Network Pharmacology ◽  
Neuroprotective Effects ◽  
Target Network ◽  
Compound Target

Background. Huangqi Sijunzi decoction (HQSJZD) is a commonly used conventional Chinese herbal medicine prescription for invigorating Qi, tonifying Yang, and removing dampness. Modern pharmacology and clinical applications of HQSJZD have shown that it has a certain curative effect on Alzheimer’s disease (AD). Methods. The active components and targets of HQSJZD were searched in the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). The genes corresponding to the targets were retrieved using UniProt and GeneCard database. The herb-compound-target network and protein-protein interaction (PPI) network were constructed by Cytoscape. The core targets of HQSJZD were analysed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The main active compounds of HQSJZD were docked with acetylcholinesterase (AChE). In vitro experiments were conducted to detect the inhibitory and neuroprotective effects of AChE. Results. Compound-target network mainly contained 132 compounds and 255 corresponding targets. The main compounds contained quercetin, kaempferol, formononetin, isorhamnetin, hederagenin, and calycosin. Key targets contained AChE, PTGS2, PPARG, IL-1B, GSK3B, etc. There were 1708 GO items in GO enrichment analysis and 310 signalling pathways in KEGG, mainly including the cAMP signalling pathway, the vascular endothelial growth factor (VEGF) signalling pathway, serotonergic synapses, the calcium signalling pathway, type II diabetes mellitus, arginine and proline metabolism, and the longevity regulating pathway. Molecular docking showed that hederagenin and formononetin were the top 2 compounds of HQSJZD, which had a high affinity with AChE. And formononetin has a good neuroprotective effect, which can improve the oxidative damage of nerve cells. Conclusion. HQSJZD was found to have the potential to treat AD by targeting multiple AD-related targets. Formononetin and hederagenin in HQSJZD may regulate multiple signalling pathways through AChE, which might play a therapeutic role in AD.

scholarly journals PhyllanthusSuppresses Prostate Cancer Cell, PC-3, Proliferation and Induces Apoptosis through Multiple Signalling Pathways (MAPKs, PI3K/Akt, NFκB, and Hypoxia)

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Yin-Quan Tang ◽  
InduBala Jaganath ◽  
Rishya Manikam ◽  
Shamala Devi Sekaran
Keyword(s):  
Molecular Mechanisms ◽  
Prostate Cancer Cell ◽  
Prostate Adenocarcinoma ◽  
Signalling Pathways ◽  
Differentially Expressed Proteins ◽  
Signalling Molecules ◽  
Anticancer Properties ◽  
Anticancer Effects ◽  
2D Gel

Phyllanthusis a traditional medicinal plant that has been found to have antihepatitis, antibacterial, and anticancer properties. The present studies were to investigate thein vitromolecular mechanisms of anticancer effects ofPhyllanthus(P. amarus, P. niruri, P. urinaria,andP. watsonii) plant extracts in human prostate adenocarcinoma. The cancer ten-pathway reporter array was performed and revealed that the expression of six pathway reporters were significantly decreased (Wnt, NFκB, Myc/Max, hypoxia, MAPK/ERK, and MAPK/JNK) in PC-3 cells after treatment withPhyllanthusextracts. Western blot was conducted and identified several signalling molecules that were affected in the signalling pathways including pan-Ras, c-Raf, RSK, Elk1, c-Jun, JNK1/2, p38 MAPK, c-myc, DSH,β-catenin, Akt, HIF-1α, GSK3β, NFκB p50 and p52, Bcl-2, Bax, and VEGF, in treated PC-3 cells. A proteomics-based approach, 2D gel electrophoresis, was performed, and mass spectrometry (MS/MS) results revealed that there were 72 differentially expressed proteins identified in treated PC-3 cells and were involved in tumour cell adhesion, apoptosis, glycogenesis and glycolysis, metastasis, angiogenesis, and protein synthesis and energy metabolism. Overall, these findings suggest thatPhyllanthuscan interfere with multiple signalling cascades involved in tumorigenesis and be used as a potential therapeutic candidate for treatment of cancer.

P-444 Presence of pharmacological inhibitors of the PI3K/PTEN/Akt and mTOR signalling pathways during cryopreservation and organotypic cultures of murine ovaries limits early primordial follicle depletion

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
C Terren ◽  
M Nisolle ◽  
C Munaut
Keyword(s):  
In Vitro Culture ◽  
Organotypic Culture ◽  
Primordial Follicle ◽  
Slow Freezing ◽  
Signalling Pathways ◽  
Primordial Follicle Activation ◽  
Mtor Signalling ◽  
Follicle Activation

Abstract Study question Which signalling pathways are implicated in primordial follicle activation induced by cryopreservation and/or organotypic culture? Is it possible to limit this activation through pharmacological inhibitors? Summary answer Our findings provide support for the hypothesis that mTOR and PI3K inhibitors might represent an attractive tool to delay cryopreservation- and culture-induced primordial follicle activation. What is known already Cryopreservation of ovarian tissue containing immature primordial follicles followed by auto-transplantation (OTCTP) is the only option available to preserve the fertility of prepubertal patients or patients requiring urgent therapy for aggressive malignancies. However, a major obstacle in this process is follicular loss immediately after grafting, possibly due to slow neovascularization, apoptosis and/or massive follicular recruitment. In vitro and in vivo studies indicate that the PI3K/PTEN/Akt and mTOR signalling pathways are involved in follicle activation. The transplantation process seems to be the major cause of primordial follicle activation after OTCTP but information about how cryopreservation itself impacts follicle activation is sparse. Study design, size, duration Whole murine ovaries (4-8-weeks old) were cryopreserved by slow freezing and exposed to LY294002 (a powerful PI3K inhibitor) or rapamycin (a specific mTOR inhibitor) during cryopreservation and/or organotypic in vitro culture for a 24 h or 2 days. Participants/materials, setting, methods Western Blot and immunofluorescence analyses were used to determine the activation of PI3K/PTEN/Akt and mTOR signalling pathways in murine ovaries cryopreserved and/or organotypically cultured with/without inhibitors.Follicles were quantified according to their maturation degree on H&E stained histological sections.  Main results and the role of chance Ratio of phosphorylated Akt or rps6 to total proteins (p-Akt/Akt and p-rps6/rps6) was increased in slow-frozen murine ovaries compared to control fresh ovaries, indicating an activation of the PI3K/PTEN/Akt and mTOR signalling pathways. The use of pharmacological inhibitors of follicle signalling pathways (LY294002 (25µM) and rapamycin (1µM)) during the cryopreservation process decreased p-Akt/Akt and p-rps6/rps6 ratios. In vitro organotypic culture for 24 h increased only the activation of the PI3K/PTEN/Akt pathway, as shown by increased p-Akt/Akt ratio in fresh ovaries cultured for 24 h compared to fresh non-cultured ovaries. This activation can be counteracted by cryopreservation of murine ovaries with rapamycin followed by in vitro culture for 24 h in the presence of LY294002. Follicle density quantifications indicated that when cryopreserved ovaries were maintained in culture for 2 days, a decrease of primordial follicle density concomitant with an increase of secondary and more mature follicles were found in comparison to slow-frozen/thawed ovaries without culture. Supplementation of the culture medium with LY294002 and rapamycin for 24 h or 2 days preserved primordial follicle densities compared to ovaries cultured without inhibitors. Limitations, reasons for caution This study is an in vitro study using murine ovaries. To analyze the efficiency of LY294002 and rapamycin to limit cryopreservation and transplantation induced follicle recruitment, these inhibitors should be tested in an in vivo model. Furthermore, these findings will need to be confirmed with human samples. Wider implications of the findings We showed for the first-time that the sequential use of pharmacological inhibitors, rapamycin during the slow freezing process followed by organotypic culture supplemented with LY294002, is effective to limit early primordial follicle depletion. Trial registration number /

Depletion of lysophosphatidic acid triggers a loss of oriented detyrosinated microtubules in motile fibroblasts

1996 ◽  
Vol 109 (10) ◽  
pp. 2461-2469 ◽  
Author(s):  
T. Nagasaki ◽  
G.G. Gundersen
Keyword(s):  
Lysophosphatidic Acid ◽  
Enzymatic Degradation ◽  
Plasma Membranes ◽  
Contact Inhibition ◽  
Signalling Pathways ◽  
Serum Factor ◽  
Motile Cells ◽  
Inhibition Response ◽  
High Concentrations

We reported earlier that isolated plasma membranes trigger a number of responses comprising contact inhibition of motility, including loss of oriented detyrosinated microtubules (Glu MTs) from the lamella of motile fibroblasts. In this study, we show that the membranes trigger this loss of Glu MTs, not by binding to cells, but by removing an essential component from the medium necessary to maintain oriented Glu MTs. Preincubation of membranes with medium containing serum followed by removal of the membranes by sedimentation rendered the membrane-treated medium capable of triggering the loss of oriented Glu MTs. Membrane activity was inhibited by high concentrations of serum and removal of serum from medium triggered the loss of oriented Glu MTs similar to that triggered by membranes. These results suggest that the membranes trigger the loss of Glu MTs by inactivating factors in serum that are required for the maintenance of oriented Glu MTs. By fractionating serum, we have identified lysophosphatidic acid (LPA) as the principal serum factor that is responsible for supporting oriented Glu MTs. The activity of LPA to maintain oriented Glu MTs upon serum withdrawal was half maximal at 100 nM and no activity was observed with structurally related phospholipids. Serum LPA levels were sufficient to account for the ability of serum to support oriented Glu MTs. Enzymatic degradation of serum LPA strongly reduced the ability of serum to support oriented Glu MTs. That membranes degrade LPA was shown by the ability of membranes to block LPA's ability to maintain oriented Glu MTs, and by direct measurement of the loss of radiolabeled LPA after incubation with membranes in vitro. These results show that isolated plasma membranes trigger the loss of Glu MTs from the lamella of motile cells by degrading serum LPA. Coupled with earlier results showing that membranes trigger a number of contact inhibition responses, our data suggest a new model for contact inhibition of motility in which local degradation of LPA and/or interference with LPA-stimulated signalling pathways initiates a contact inhibition response in colliding cells.

Growth factor-induced activation of a kinase activity which causes regulatory phosphorylation of p42/microtubule-associated protein kinase

1992 ◽  
Vol 12 (5) ◽  
pp. 2222-2229
Author(s):  
G L'Allemain ◽  
J H Her ◽  
J Wu ◽  
T W Sturgill ◽  
M J Weber
Keyword(s):  
Growth Factor ◽  
Protein Kinase ◽  
Kinase Activity ◽  
Growth Control ◽  
Signalling Pathways ◽  
3T3 Cells ◽  
Regulatory Phosphorylation ◽  
Enzymatic Activation

p42/microtubule-associated protein kinase (p42mapk) is activated by tyrosine and threonine phosphorylation, and its regulatory phosphorylation is likely to be important in signalling pathways involved in growth control, secretion, and differentiation. Here we show that treatment of quiescent 3T3 cells with diverse agonists results in the appearance of an activity capable of causing the in vitro phosphorylation of p42mapk on the regulatory tyrosine and to a lesser extent on the regulatory threonine, resulting in enzymatic activation of the p42mapk. This p42mapk-activating activity is capable of phosphorylating a kinase-defective p42mapk mutant, thus confirming its activity as a kinase.

scholarly journals Expression of human colony-stimulating factor-1 (CSF-1) receptor in murine pluripotent hematopoietic NFS-60 cells induces long-term proliferation in response to CSF-1 without loss of erythroid differentiation potential

Blood ◽  
1993 ◽  
Vol 81 (10) ◽  
pp. 2511-2520 ◽  
Author(s):  
RP Bourette ◽  
G Mouchiroud ◽  
R Ouazana ◽  
F Morle ◽  
J Godet ◽  
...  
Keyword(s):  
Receptor Gene ◽  
Erythroid Differentiation ◽  
Signalling Pathways ◽  
Colony Stimulating Factor ◽  
Differentiation Potential ◽  
Self Renewal ◽  
Multipotent Cells ◽  
Stimulating Factor

Abstract NFS-60 and FDCP-Mix cells are interleukin-3--dependent multipotent hematopoietic cells that can differentiate in vitro into mature myeloid and erythroid cells. Retrovirus-mediated transfer of the human colony- stimulating factor-1 (CSF-1) receptor gene (c-fms) enabled NFS-60 cells but not FDCP-Mix cells to proliferate in response to CSF-1. The phenotype of NFS-60 cells expressing the human CSF-1 receptor (CSF-1R) grown in CSF-1 did not grossly differ from that of original NFS-60 as assessed by cytochemical and surface markers. Importantly, these cells retained their erythroid potentiality. In contrast, a CSF-1-dependent variant of NFS-60, strongly expressing murine CSF-1R, differentiated into monocyte/macrophages upon CSF-1 stimulation and almost totally lost its erythroid potentiality. We also observed that NFS-60 but not FDCP-Mix cells could grow in response to stem cell factor, (SCF), although both cell lines express relatively high amounts of SCF receptors. This suggests that SCF-R and CSF-1R signalling pathways share at least one component that may be missing or insufficiently expressed in FDCP-Mix cells. Taken together, these results suggest that human CSF-1R can use the SCF-R signalling pathway in murine multipotent cells and thereby favor self-renewal versus differentiation.

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