Decrease in Membrane Fluidity and Traction Force Induced by Silica-Coated Magnetic Nanoparticles

Abstract Background Nanoparticles are being used increasingly due to their unique physical and chemical properties and small size. It is well-known that nanoparticles cause side effects, however their biophysical assessment remains challenging. We addressed this issue by investigating the effects of silica-coated magnetic nanoparticles containing rhodamine B isothiocyanate [MNPs@SiO2(RITC)] on the biophysical aspects, such as membrane fluidity and traction force of human embryonic kidney 293 (HEK293) cells. We further extended our understanding on the biophysical effects of nanoparticles on cells using a combination of metabolic profiling and transcriptomic network analysis. Results Overdose (1.0 μg/µl) treatment of MNPs@SiO2(RITC) induced lipid peroxidation and decreased membrane fluidity in HEK293 cells. During membrane damage, HEK293 cells were morphologically shrunk and aspect ratio of the cells were significantly decreased upon MNPs@SiO2(RITC) treatment. Each of traction force (measured in micropillar) was found to be increased, thereby increasing the total traction force in MNPs@SiO2(RITC)-treated HEK293 cells. Due to the reduction in membrane fluidity and elevation of traction force, velocity of the cell movement was significantly decreased in MNPs@SiO2(RITC)-treated HEK293 cells. Moreover, intracellular ATP also decreased in a dose dependent manner upon MNPs@SiO2(RITC) treatment. To understand the biophysical changes in cells, we analysed transcriptome and metabolic profiles and generated metabotranscriptomics network. The network showed relationships among peroxidation of lipid, focal adhesion, cell movement, and related genes and metabolites. Furthermore, in silico prediction of the network showed increment in the peroxidation of lipid and suppression of focal adhesion and cell movement.Conclusion Taken together, our results demonstrate that overdosage of MNPs@SiO2(RITC) impairs cellular movement, followed by changes in the biophysical properties of cells, thus highlighting the need for biophysical assessment of nanoparticle-induced side effects.

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Silica-Coated Magnetic Nanoparticles Decrease Human Bone Marrow-Derived Mesenchymal Stem Cell Migratory Activity by Reducing Membrane Fluidity and Impairing Focal Adhesion

Nanomaterials ◽

10.3390/nano9101475 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1475 ◽

Cited By ~ 4

Author(s):

Tae Hwan Shin ◽

Da Yeon Lee ◽

Abdurazak Aman Ketebo ◽

Seungah Lee ◽

Balachandran Manavalan ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Stem Cell ◽

Magnetic Nanoparticles ◽

Cell Viability ◽

Membrane Fluidity ◽

Traction Force ◽

Biological Functions ◽

Migratory Activity ◽

Biophysical Effects

For stem cell-based therapies, the fate and distribution of stem cells should be traced using non-invasive or histological methods and a nanomaterial-based labelling agent. However, evaluation of the biophysical effects and related biological functions of nanomaterials in stem cells remains challenging. Here, we aimed to investigate the biophysical effects of nanomaterials on stem cells, including those on membrane fluidity, using total internal reflection fluorescence microscopy, and traction force, using micropillars of human bone marrow-derived mesenchymal stem cells (hBM-MSCs) labelled with silica-coated magnetic nanoparticles incorporating rhodamine B isothiocyanate (MNPs@SiO2(RITC)). Furthermore, to evaluate the biological functions related to these biophysical changes, we assessed the cell viability, reactive oxygen species (ROS) generation, intracellular cytoskeleton, and the migratory activity of MNPs@SiO2(RITC)-treated hBM-MSCs. Compared to that in the control, cell viability decreased by 10% and intracellular ROS increased by 2-fold due to the induction of 20% higher peroxidized lipid in hBM-MSCs treated with 1.0 µg/µL MNPs@SiO2(RITC). Membrane fluidity was reduced by MNPs@SiO2(RITC)-induced lipid oxidation in a concentration-dependent manner. In addition, cell shrinkage with abnormal formation of focal adhesions and ~30% decreased total traction force were observed in cells treated with 1.0 µg/µL MNPs@SiO2(RITC) without specific interaction between MNPs@SiO2(RITC) and cytoskeletal proteins. Furthermore, the migratory activity of hBM-MSCs, which was highly related to membrane fluidity and cytoskeletal abnormality, decreased significantly after MNPs@SiO2(RITC) treatment. These observations indicated that the migratory activity of hBM-MSCs was impaired by MNPs@SiO2(RITC) treatment due to changes in stem-cell biophysical properties and related biological functions, highlighting the important mechanisms via which nanoparticles impair migration of hBM-MSCs. Our findings indicate that nanoparticles used for stem cell trafficking or clinical applications should be labelled using optimal nanoparticle concentrations to preserve hBM-MSC migratory activity and ensure successful outcomes following stem cell localisation.

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Poldip2 controls vascular smooth muscle cell migration by regulating focal adhesion turnover and force polarization

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00918.2013 ◽

2014 ◽

Vol 307 (7) ◽

pp. H945-H957 ◽

Cited By ~ 30

Author(s):

Srinivasa Raju Datla ◽

Daniel J. McGrail ◽

Sasa Vukelic ◽

Lauren P. Huff ◽

Alicia N. Lyle ◽

...

Keyword(s):

Smooth Muscle ◽

Vascular Smooth Muscle ◽

Focal Adhesion ◽

Focal Adhesions ◽

Traction Force ◽

Force Generation ◽

Dependent Manner ◽

Interacting Protein ◽

Nadph Oxidase 4 ◽

Focal Adhesion Turnover

Polymerase-δ-interacting protein 2 (Poldip2) interacts with NADPH oxidase 4 (Nox4) and regulates migration; however, the precise underlying mechanisms are unclear. Here, we investigated the role of Poldip2 in focal adhesion turnover, as well as traction force generation and polarization. Poldip2 overexpression (AdPoldip2) in vascular smooth muscle cells (VSMCs) impairs PDGF-induced migration and induces a characteristic phenotype of long cytoplasmic extensions. AdPoldip2 also prevents the decrease in spreading and increased aspect ratio observed in response to PDGF and slightly impairs cell contraction. Moreover, AdPoldip2 blocks focal adhesion dissolution and sustains H2O2 levels in focal adhesions, whereas Poldip2 knockdown (siPoldip2) significantly decreases the number of focal adhesions. RhoA activity is unchanged when focal adhesion dissolution is stimulated in control cells but increases in AdPoldip2-treated cells. Inhibition of RhoA blocks Poldip2-mediated attenuation of focal adhesion dissolution, and overexpression of RhoA or focal adhesion kinase (FAK) reverses the loss of focal adhesions induced by siPoldip2, indicating that RhoA and FAK mediate the effect of Poldip2 on focal adhesions. Nox4 silencing prevents focal adhesion stabilization by AdPoldip2 and induces a phenotype similar to siPoldip2, suggesting a role for Nox4 in Poldip2-induced focal adhesion stability. As a consequence of impaired focal adhesion turnover, PDGF-treated AdPoldip2 cells are unable to reduce and polarize traction forces, a necessary first step in migration. These results implicate Poldip2 in VSMC migration via regulation of focal adhesion turnover and traction force generation in a Nox4/RhoA/FAK-dependent manner.

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Mechanisms contributing to ado-trastuzumab emtansine (T-DM1)-induced toxicities: a gateway to better understanding ADC-associated toxicities

Antibody Therapeutics ◽

10.1093/abt/tbab005 ◽

2021 ◽

Author(s):

Yukinori Endo ◽

Nishant Mohan ◽

Milos Dokmanovic ◽

Wen Jin Wu

Keyword(s):

Breast Cancer ◽

Side Effects ◽

Metastatic Breast ◽

Invasive Disease ◽

Dependent Manner ◽

Trastuzumab Emtansine ◽

Antibody Drug Conjugate ◽

Her2 Positive ◽

Humanized Monoclonal Antibody ◽

Significant Efficacy

Abstract In order to improve the safety of novel therapeutic drugs, better understanding of the mechanisms of action is important. Ado-trastuzumab emtansine (also known as T-DM1) is an antibody-drug conjugate (ADC) consisting of a humanized monoclonal antibody directed against HER2 (trastuzumab) and a maytansinoid-derived toxin (DM1), which are linked by a non-cleavable thioether linker. T-DM1 has been approved for the treatment of trastuzumab-resistant HER2-positive metastatic breast cancer and recently for use as an adjuvant treatment option for patients with HER2-positive early breast cancer who have residual invasive disease. While the treatment with T-DM1 results in significant efficacy in the selected patient population, nonetheless, there are also concerns with the side effects such as thrombocytopenia and hepatotoxicity. While current understanding of the mechanism of T-DM1-mediated side effects is still incomplete, there have been several reports of HER2-dependent and/or -independent mechanisms that could be associated with the T-DM1-induced adverse events. The results from our laboratory show that T-DM1 binds to cytoskeleton-associated protein 5 (CKAP5) on the cell surface of hepatocytes via its payload component (DM1). This interaction is independent of HER2 and leads to cell growth inhibition and apoptosis of hepatocytes in a T-DM1 dose dependent manner. This review highlights the importance of HER2-independent mechanism of T-DM1 to induce hepatotoxicity, which offers a new insight into a role for CKAP5 in the overall maytansinoid-based ADC (DM1 and DM4)-mediated cytotoxicity. This discovery provides a molecular basis for T-DM1-induced off-target toxicity and opens a new avenue for developing the next generation of ADCs.

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Hexagonal boron nitride nanoparticles trigger oxidative stress by modulating thiol/disulfide homeostasis

Human & Experimental Toxicology ◽

10.1177/09603271211002892 ◽

2021 ◽

pp. 096032712110028

Author(s):

F Kar ◽

İ Söğüt ◽

C Hacıoğlu ◽

Y Göncü ◽

H Şenturk ◽

...

Keyword(s):

Oxidative Stress ◽

Boron Nitride ◽

Hexagonal Boron Nitride ◽

Chemical Properties ◽

Heart Tissue ◽

Albino Rats ◽

Dependent Manner ◽

Tissue Samples ◽

Boron Nitride Nanoparticles

Background: Hexagonal boron nitride nanoparticles (hBN NPs) are encouraging nanomaterials with unique chemical properties in medicine and biomedical fields. Until now, the optimal hBN NP’s dosage and biochemical mechanism that can be used for in vivo systems has not been fully revealed. The main aim of this article is to reveal characteristics, serum and tissue interactions and any acute cytotoxic effect of different dose of hBN NPs for the first time. Methods: hBN NPs at concentrations varying between 50–3200 µg/kg was administered by intravenous injection to Wistar albino rats (n = 80) divided into seven dosage and control groups. Blood and tissue samples were taken after 24 hours. Results: Our findings suggested that higher doses hBN NPs caused oxidative stress on the serum of rats dose-dependently. However, hBN NPs did not affect thiol/disulfide homeostasis on kidney, liver, spleen, pancreas and heart tissue of rats. Furthermore, hBN NPs increased serum disulfide formation by disrupting the thiol/disulfide balance in rats. Also, LOOH and MPO levels increased at high doses, while CAT levels decreased statistically. Conclusion: The results revealed that hBN NPs induce oxidative stress in a dose-dependent manner by modulating thiol/disulfide homeostasis in rats at higher concentrations

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The Novel ALG-2 Target Protein CDIP1 Promotes Cell Death by Interacting with ESCRT-I and VAPA/B

International Journal of Molecular Sciences ◽

10.3390/ijms22031175 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1175

Author(s):

Ryuta Inukai ◽

Kanako Mori ◽

Keiko Kuwata ◽

Chihiro Suzuki ◽

Masatoshi Maki ◽

...

Keyword(s):

Cell Death ◽

Essential Gene ◽

Susceptibility Gene ◽

Target Protein ◽

Hek293 Cells ◽

Dependent Manner ◽

Gene Encoding ◽

Endosomal Sorting ◽

Cell Death Pathways ◽

Apoptotic Protein

Apoptosis-linked gene 2 (ALG-2, also known as PDCD6) is a member of the penta-EF-hand (PEF) family of Ca2+-binding proteins. The murine gene encoding ALG-2 was originally reported to be an essential gene for apoptosis. However, the role of ALG-2 in cell death pathways has remained elusive. In the present study, we found that cell death-inducing p53 target protein 1 (CDIP1), a pro-apoptotic protein, interacts with ALG-2 in a Ca2+-dependent manner. Co-immunoprecipitation analysis of GFP-fused CDIP1 (GFP-CDIP1) revealed that GFP-CDIP1 associates with tumor susceptibility gene 101 (TSG101), a known target of ALG-2 and a subunit of endosomal sorting complex required for transport-I (ESCRT-I). ESCRT-I is a heterotetrameric complex composed of TSG101, VPS28, VPS37 and MVB12/UBAP1. Of diverse ESCRT-I species originating from four VPS37 isoforms (A, B, C, and D), CDIP1 preferentially associates with ESCRT-I containing VPS37B or VPS37C in part through the adaptor function of ALG-2. Overexpression of GFP-CDIP1 in HEK293 cells caused caspase-3/7-mediated cell death. In addition, the cell death was enhanced by co-expression of ALG-2 and ESCRT-I, indicating that ALG-2 likely promotes CDIP1-induced cell death by promoting the association between CDIP1 and ESCRT-I. We also found that CDIP1 binds to vesicle-associated membrane protein-associated protein (VAP)A and VAPB through the two phenylalanines in an acidic tract (FFAT)-like motif in the C-terminal region of CDIP1, mutations of which resulted in reduction of CDIP1-induced cell death. Therefore, our findings suggest that different expression levels of ALG-2, ESCRT-I subunits, VAPA and VAPB may have an impact on sensitivity of anticancer drugs associated with CDIP1 expression.

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Chemotactic Responses of Jurkat Cells in Microfluidic Flow-Free Gradient Chambers

Micromachines ◽

10.3390/mi11040384 ◽

2020 ◽

Vol 11 (4) ◽

pp. 384 ◽

Cited By ~ 1

Author(s):

Utku M. Sonmez ◽

Adam Wood ◽

Kyle Justus ◽

Weijian Jiang ◽

Fatima Syed-Picard ◽

...

Keyword(s):

Immune Response ◽

Cancer Progression ◽

Soft Lithography ◽

Cell Movement ◽

Population Level ◽

Jurkat Cells ◽

Dependent Manner ◽

Diverse Range ◽

Microfluidic Flow ◽

Cell Motion

Gradients of soluble molecules coordinate cellular communication in a diverse range of multicellular systems. Chemokine-driven chemotaxis is a key orchestrator of cell movement during organ development, immune response and cancer progression. Chemotaxis assays capable of examining cell responses to different chemokines in the context of various extracellular matrices will be crucial to characterize directed cell motion in conditions which mimic whole tissue conditions. Here, a microfluidic device which can generate different chemokine patterns in flow-free gradient chambers while controlling surface extracellular matrix (ECM) to study chemotaxis either at the population level or at the single cell level with high resolution imaging is presented. The device is produced by combining additive manufacturing (AM) and soft lithography. Generation of concentration gradients in the device were simulated and experimentally validated. Then, stable gradients were applied to modulate chemotaxis and chemokinetic response of Jurkat cells as a model for T lymphocyte motility. Live imaging of the gradient chambers allowed to track and quantify Jurkat cell migration patterns. Using this system, it has been found that the strength of the chemotactic response of Jurkat cells to CXCL12 gradient was reduced by increasing surface fibronectin in a dose-dependent manner. The chemotaxis of the Jurkat cells was also found to be governed not only by the CXCL12 gradient but also by the average CXCL12 concentration. Distinct migratory behaviors in response to chemokine gradients in different contexts may be physiologically relevant for shaping the host immune response and may serve to optimize the targeting and accumulation of immune cells to the inflammation site. Our approach demonstrates the feasibility of using a flow-free gradient chamber for evaluating cross-regulation of cell motility by multiple factors in different biologic processes.

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Polymeric Mesoporous Silica Nanoparticles for Enhanced Delivery of 5-Fluorouracil In Vitro

Pharmaceutics ◽

10.3390/pharmaceutics11060288 ◽

2019 ◽

Vol 11 (6) ◽

pp. 288 ◽

Cited By ~ 19

Author(s):

Thashini Moodley ◽

Moganavelli Singh

Keyword(s):

Side Effects ◽

Mesoporous Silica ◽

Silica Nanoparticles ◽

Therapeutic Potential ◽

Mesoporous Silica Nanoparticles ◽

Drug Loading ◽

Hek293 Cells ◽

Cancer Drug ◽

Delivery Vehicles

There is a need for the improvement of conventional cancer treatment strategies by incorporation of targeted and non-invasive procedures aimed to reduce side-effects, drug resistance, and recurrent metastases. The anti-cancer drug, 5-fluorouracil (5-FU), is linked to a variety of induced-systemic toxicities due to its lack of specificity and potent administration regimens, necessitating the development of delivery vehicles that can enhance its therapeutic potential, while minimizing associated side-effects. Polymeric mesoporous silica nanoparticles (MSNs) have gained popularity as delivery vehicles due to their high loading capacities, biocompatibility, and good pharmacokinetics. MSNs produced in this study were functionalized with the biocompatible polymers, chitosan, and poly(ethylene)glycol to produce monodisperse NPs of 36–65 nm, with a large surface area of 710.36 m2/g, large pore volume, diameter spanning 9.8 nm, and a favorable zeta potential allowing for stability and enhanced uptake of 5-FU. Significant drug loading (0.15–0.18 mg5FU/mgmsn), controlled release profiles (15–65%) over 72 hours, and cell specific cytotoxicity in cancer cells (Caco-2, MCF-7, and HeLa) with reduced cell viability (≥50%) over the non-cancer (HEK293) cells were established. Overall, these 5FU-MSN formulations have been shown to be safe and effective delivery systems in vitro, with potential for in vivo applications.

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Mechanical Control of Cell Migration by the Metastasis Suppressor Tetraspanin CD82/KAI1

Cells ◽

10.3390/cells10061545 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1545

Author(s):

Laura Ordas ◽

Luca Costa ◽

Anthony Lozano ◽

Christopher Chevillard ◽

Alexia Calovoulos ◽

...

Keyword(s):

Cell Migration ◽

Cell Surface ◽

Focal Adhesion ◽

Nuclear Translocation ◽

Single Cells ◽

Integral Membrane Protein ◽

Metastasis Suppressor ◽

Dependent Manner ◽

Strong Inhibitor ◽

Caveolin 1

The plasma membrane is a key actor of cell migration. For instance, its tension controls persistent cell migration and cell surface caveolae integrity. Then, caveolae constituents such as caveolin-1 can initiate a mechanotransduction loop that involves actin- and focal adhesion-dependent control of the mechanosensor YAP to finely tune cell migration. Tetraspanin CD82 (also named KAI-1) is an integral membrane protein and a metastasis suppressor. Its expression is lost in many cancers including breast cancer. It is a strong inhibitor of cell migration by a little-known mechanism. We demonstrated here that CD82 controls persistent 2D migration of EGF-induced single cells, stress fibers and focal adhesion sizes and dynamics. Mechanistically, we found that CD82 regulates membrane tension, cell surface caveolae abundance and YAP nuclear translocation in a caveolin-1-dependent manner. Altogether, our data show that CD82 controls 2D cell migration using membrane-driven mechanics involving caveolin and the YAP pathway.

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The G protein βγ subunit mediates reannealing of adherens junctions to reverse endothelial permeability increase by thrombin

Journal of Experimental Medicine ◽

10.1084/jem.20090652 ◽

2009 ◽

Vol 206 (12) ◽

pp. 2761-2777 ◽

Cited By ~ 58

Author(s):

Nebojsa Knezevic ◽

Mohammad Tauseef ◽

Tracy Thennes ◽

Dolly Mehta

Keyword(s):

Vascular Permeability ◽

Focal Adhesion ◽

Inflammatory Mediator ◽

Adherens Junctions ◽

Endothelial Permeability ◽

Endothelial Barrier ◽

Dependent Manner ◽

Permeability Increase ◽

Lung Vascular Permeability

The inflammatory mediator thrombin proteolytically activates protease-activated receptor (PAR1) eliciting a transient, but reversible increase in vascular permeability. PAR1-induced dissociation of Gα subunit from heterotrimeric Gq and G12/G13 proteins is known to signal the increase in endothelial permeability. However, the role of released Gβγ is unknown. We now show that impairment of Gβγ function does not affect the permeability increase induced by PAR1, but prevents reannealing of adherens junctions (AJ), thereby persistently elevating endothelial permeability. We observed that in the naive endothelium Gβ1, the predominant Gβ isoform is sequestered by receptor for activated C kinase 1 (RACK1). Thrombin induced dissociation of Gβ1 from RACK1, resulting in Gβ1 interaction with Fyn and focal adhesion kinase (FAK) required for FAK activation. RACK1 depletion triggered Gβ1 activation of FAK and endothelial barrier recovery, whereas Fyn knockdown interrupted with Gβ1-induced barrier recovery indicating RACK1 negatively regulates Gβ1-Fyn signaling. Activated FAK associated with AJ and stimulated AJ reassembly in a Fyn-dependent manner. Fyn deletion prevented FAK activation and augmented lung vascular permeability increase induced by PAR1 agonist. Rescuing FAK activation in fyn−/− mice attenuated the rise in lung vascular permeability. Our results demonstrate that Gβ1-mediated Fyn activation integrates FAK with AJ, preventing persistent endothelial barrier leakiness.

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