scholarly journals Toxicological Implications of Platinum Nanoparticle Exposure: Stimulation of Intracellular Stress, Inflammatory Response, and Akt Signaling In Vitro

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Claudia J. Labrador-Rached ◽  
Rebecca T. Browning ◽  
Laura K. Braydich-Stolle ◽  
Kristen K. Comfort
Keyword(s):  
Stress Responses ◽  
Health And Safety ◽  
Cellular Responses ◽  
Cellular Interactions ◽  
Platinum Nanoparticle ◽  
Liver Model ◽  
Dependent Signal ◽  
Cell Functionality

Due to their distinctive physicochemical properties, platinum nanoparticles (PtNPs) have emerged as a material of interest for a number of biomedical therapeutics. However, in some instances NP exposure has been correlated to health and safety concerns, including cytotoxicity, activation of cellular stress, and modification to normal cell functionality. As PtNPs have induced differential cellular responses in vitro, the goal of this study was to further characterize the behavior and toxicological potential of PtNPs within a HepG2 liver model. This study identified that a high PtNP dosage induced HepG2 cytotoxicity. However, lower, subtoxic PtNP concentrations were able to elicit multiple stress responses, secretion of proinflammatory cytokines, and modulation of insulin-like growth factor-1 dependent signal transduction. Taken together, this work suggests that PtNPs would not be overtly toxic for acute exposures, but sustained cellular interactions might produce long term health consequences.

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.

scholarly journals Phylogenetic analysis of plant multi-domain SEC14-like phosphatidylinositol transfer proteins and structure–function properties of PATELLIN2

2020 ◽  
Vol 104 (6) ◽  
pp. 665-678
Author(s):  
Karolin Montag ◽  
Jannik Hornbergs ◽  
Rumen Ivanov ◽  
Petra Bauer
Keyword(s):  
Structure Function ◽  
Green Algae ◽  
Stress Responses ◽  
Land Plants ◽  
Modular Structure ◽  
Flowering Plant ◽  
Cellular Interactions ◽  
Phosphatidylinositol Transfer ◽  
Phosphatidylinositol Transfer Proteins

Abstract Key message SEC14L-PITPs guide membrane recognition and signaling. An increasingly complex modular structure of SEC14L-PITPs evolved in land plants compared to green algae. SEC14/CRAL-TRIO and GOLD domains govern membrane binding specificity. Abstract SEC14-like phosphatidylinositol transfer proteins (SEC14L-PITPs) provide cues for membrane identity by exchanging lipophilic substrates, ultimately governing membrane signaling. Flowering plant SEC14L-PITPs often have modular structure and are associated with cell division, development, and stress responses. Yet, structure–function relationships for biochemical–cellular interactions of SEC14L-PITPs are rather enigmatic. Here, we evaluate the phylogenetic relationships of the SEC14L-PITP superfamily in the green lineage. Compared to green algae, land plants have an extended set of SEC14L-PITPs with increasingly complex modular structure. SEC14-GOLD PITPs, present in land plants but not Chara, diverged to three functional subgroups, represented by the six PATELLIN (PATL) proteins in Arabidopsis. Based on the example of Arabidopsis PATL2, we dissect the functional domains for in vitro binding to phosphoinositides and liposomes and for plant cell membrane association. While the SEC14 domain and its CRAL-TRIO-N-terminal extension serve general membrane attachment of the protein, the C-terminal GOLD domain directs it to the plasma membrane by recognizing specific phosphoinositides. We discuss that the different domains of SEC14L-PITPs integrate developmental and environmental signals to control SEC14L-PITP-mediated membrane identity, important to initiate dynamic membrane events.

scholarly journals Potentiality, Limitations, and Consequences of Different Experimental Models to Improve Photodynamic Therapy for Cancer Treatment in Relation to Antiangiogenic Mechanism

Cancers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2118
Author(s):  
Martin Majerník ◽  
Rastislav Jendželovský ◽  
Peter Fedoročko
Keyword(s):  
Photodynamic Therapy ◽  
In Vitro Models ◽  
Experimental Models ◽  
Cellular Interactions ◽  
Wide Range ◽  
Therapy Effect ◽  
Complex Features ◽  
Complex Phenomena

The relevance of experimentally gained information represents a long-term debating issue in the field of molecular biology research. The loss of original conditions in the in vitro environment affects various biological mechanisms and cellular interactions. Consequently, some biochemical mechanisms are lost or critically altered. Analyses in these modified conditions could, therefore, distort the relevancy of experimentally gained information. In some cases, the similarities with original conditions are so small that utilization of simpler in vitro models seems impossible, or could occur in a very limited way. To conclude, the study of more complex phenomena places higher demands on the complexity of the experimental model. The latest information highlights the fact that the tumor angiogenesis mechanism has very complex features. This complexity can be associated with a wide range of angiogenic factors expressed by a variety of malignant and non-malignant cells. Our article summarizes the results from various experimental models that were utilized to analyze a photodynamic therapy effect on tumor angiogenic mechanisms. Additionally, based on the latest information, we present the most important attributes and limitations of utilized experimental models. We also evaluate the essential problems associated with angiogenic mechanism induction after photodynamic therapy application.

scholarly journals An in-depth multi-omics analysis in RLE-6TN rat alveolar epithelial cells allows for nanomaterial categorization

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Isabel Karkossa ◽  
Anne Bannuscher ◽  
Bryan Hellack ◽  
Aileen Bahl ◽  
Sophia Buhs ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Stress Responses ◽  
Chemical Properties ◽  
Cellular Responses ◽  
Alveolar Epithelial Cells ◽  
Alveolar Epithelial ◽  
Physico Chemical ◽  
Key Drivers

Abstract Background Nanomaterials (NMs) can be fine-tuned in their properties resulting in a high number of variants, each requiring a thorough safety assessment. Grouping and categorization approaches that would reduce the amount of testing are in principle existing for NMs but are still mostly conceptual. One drawback is the limited mechanistic understanding of NM toxicity. Thus, we conducted a multi-omics in vitro study in RLE-6TN rat alveolar epithelial cells involving 12 NMs covering different materials and including a systematic variation of particle size, surface charge and hydrophobicity for SiO2 NMs. Cellular responses were analyzed by global proteomics, targeted metabolomics and SH2 profiling. Results were integrated using Weighted Gene Correlation Network Analysis (WGCNA). Results Cluster analyses involving all data sets separated Graphene Oxide, TiO2_NM105, SiO2_40 and Phthalocyanine Blue from the other NMs as their cellular responses showed a high degree of similarities, although apical in vivo results may differ. SiO2_7 behaved differently but still induced significant changes. In contrast, the remaining NMs were more similar to untreated controls. WGCNA revealed correlations of specific physico-chemical properties such as agglomerate size and redox potential to cellular responses. A key driver analysis could identify biomolecules being highly correlated to the observed effects, which might be representative biomarker candidates. Key drivers in our study were mainly related to oxidative stress responses and apoptosis. Conclusions Our multi-omics approach involving proteomics, metabolomics and SH2 profiling proved useful to obtain insights into NMs Mode of Actions. Integrating results allowed for a more robust NM categorization. Moreover, key physico-chemical properties strongly correlating with NM toxicity were identified. Finally, we suggest several key drivers of toxicity that bear the potential to improve future testing and assessment approaches.

scholarly journals Persistent Oxidative Stress and Inflammasome Activation in CD14highCD16− Monocytes From COVID-19 Patients

2022 ◽  
Vol 12 ◽  
Author(s):  
Silvia Lucena Lage ◽  
Eduardo Pinheiro Amaral ◽  
Kerry L. Hilligan ◽  
Elizabeth Laidlaw ◽  
Adam Rupert ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Lipid Peroxidation ◽  
Stress Responses ◽  
Inflammasome Activation ◽  
Strongly Correlated ◽  
Long Term Outcomes ◽  
Caspase 1 ◽  
Mitochondrial Superoxide

The poor outcome of the coronavirus disease-2019 (COVID-19), caused by SARS-CoV-2, is associated with systemic hyperinflammatory response and immunopathology. Although inflammasome and oxidative stress have independently been implicated in COVID-19, it is poorly understood whether these two pathways cooperatively contribute to disease severity. Herein, we found an enrichment of CD14highCD16− monocytes displaying inflammasome activation evidenced by caspase-1/ASC-speck formation in severe COVID-19 patients when compared to mild ones and healthy controls, respectively. Those cells also showed aberrant levels of mitochondrial superoxide and lipid peroxidation, both hallmarks of the oxidative stress response, which strongly correlated with caspase-1 activity. In addition, we found that NLRP3 inflammasome-derived IL-1β secretion by SARS-CoV-2-exposed monocytes in vitro was partially dependent on lipid peroxidation. Importantly, altered inflammasome and stress responses persisted after short-term patient recovery. Collectively, our findings suggest oxidative stress/NLRP3 signaling pathway as a potential target for host-directed therapy to mitigate early COVID-19 hyperinflammation and also its long-term outcomes.

scholarly journals Persistent oxidative stress and inflammasome activation in CD14highCD16- monocytes from COVID-19 patients

2021 ◽  
Author(s):  
Silvia Lucena Lage ◽  
Eduardo Pinheiro Amaral ◽  
kerry L. Hilligan ◽  
Elizabeth Laidlaw ◽  
Adam Rupert ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Lipid Peroxidation ◽  
Stress Responses ◽  
Inflammasome Activation ◽  
Strongly Correlated ◽  
Long Term Outcomes ◽  
Caspase 1 ◽  
Mitochondrial Superoxide

The poor outcome of the coronavirus disease-2019 (COVID-19), caused by SARS-CoV-2, is associated with systemic hyperinflammatory response and immunopathology. Although inflammasome and oxidative stress have independently been implicated in COVID-19, it is poorly understood whether these two pathways cooperatively contribute to disease severity. Herein, we found an enrichment of CD14highCD16- monocytes displaying inflammasome activation evidenced by caspase-1/ASC-speck formation in severe COVID-19 patients when compared to mild ones and healthy controls, respectively. Those cells also showed aberrant levels of mitochondrial superoxide (MitoSOX) and lipid peroxidation, both hallmarks of the oxidative stress response, which strongly correlated with caspase-1 activity. In addition, we found that NLRP3 inflammasome-derived IL-1β secretion by SARS-CoV-2-exposed monocytes in vitro was partially dependent on lipid peroxidation. Importantly, altered inflammasome and stress responses persisted after short-term patient recovery. Collectively, our findings suggest oxidative stress/NLRP3 signaling pathway as a potential target for host-directed therapy to mitigate early COVID-19 hyperinflammation as well as its long-term outcomes.

Protein in culture and endogenous lipid interact with embryonic stages in vitro to alter calf birthweight after embryo vitrification and warming

2017 ◽  
Vol 29 (10) ◽  
pp. 1932 ◽  
Author(s):  
E. Gómez ◽  
S. Carrocera ◽  
S. Uzbekova ◽  
D. Martín ◽  
A. Murillo ◽  
...  
Keyword(s):  
Stress Responses ◽  
Regulatory Element ◽  
Pregnancy Rates ◽  
Hormone Sensitive Lipase ◽  
Expression Of Genes ◽  
Element Binding Protein ◽  
Sterol Regulatory Element ◽  
Hormone Sensitive

Short-term protein removal in vitro improves long-term blastocyst competence to survive vitrification. We investigated the mechanisms and effects underlying protein removal. Day-6 morulae and early blastocysts were cultured individually with and without protein for 24 h. Development and lipid content were analysed in expanded blastocysts derived from morulae (M-XB) and from early blastocysts (EB-XB). Expression of genes involved in lipid metabolism, stress responses and apoptosis was analysed in fresh and vitrified–warmed M-XB produced with and without protein. Pregnancy rates, birth rates and birthweight (BW) were recorded after transfer of embryos. Day-7 EB-XB production rates (with, 66.9 ± 6.2 and without, 68.8 ± 6.0 protein) were higher than M-XB rates (with, 21.4 ± 4.6 and without, 9.4 ± 4.6 protein; P < 0.005). EB-XB showed fewer lipids than M-XB (P = 0.03). In fresh M-XB, expression of sterol regulatory element binding protein (SREBP1) was lower with (4.1 ± 2.2) than without (13.6 ± 2.2) protein, contrary to results obtained for Patatin-like phospholipase domain containing 2, Hormone-sensitive lipase and Bcl-2–associated X protein (P < 0.05). Protein did not affect pregnancy rates and birth phenotypes (P > 0.05). However, BW was higher (P < 0.01) in calves born from vitrified M-XB (48.6 ± 3.4 kg) than from EB-XB (39.8 ± 2.9 kg). Such effects were more pronounced in females (P < 0.001). Calves from fresh embryos did not show BW differences. These results indicate that embryonic kinetics and vitrification impact birth phenotypes, at least in females. Alterations might involve exogenous protein and mobilisation of lipid stocks.

Correlated Studies of Cellular Interactions Using TEM, Freeze Etching, and SEM

1974 ◽  
Vol 32 ◽  
pp. 320-321
Author(s):  
J. P. Revel
Keyword(s):  
Developmental Stages ◽  
Three Dimensional ◽  
Cell Movement ◽  
Cellular Interactions ◽  
Serial Sections ◽  
Cell Sheets ◽  
Freeze Etching ◽  
Early Developmental

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.

Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte

1990 ◽  
Vol 48 (3) ◽  
pp. 374-375
Author(s):  
D.E. Loudy ◽  
J. Sprinkle-Cavallo ◽  
J.T. Yarrington ◽  
F.Y. Thompson ◽  
J.P. Gibson
Keyword(s):  
Antidepressant Drug ◽  
Beagle Dogs ◽  
Long Term Effects ◽  
Short Term ◽  
Platelet Counts ◽  
Toxicological Studies ◽  
Induced Aggregation ◽  
Internal Architecture

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.

Sign in / Sign up

Export Citation Format

Share Document