Liposomal Nanocarriers Designed for Subendothelial Matrix Targeting Under Vascular Sheer Stress

Abstract It has been shown that bone cells are more responsive to fluid flow induced shear stress as compared to applied substrate strain (Owan, et al., 1997, Smalt, et al., 1997). Using novel micromechanical analysis techniques, we have measured individual cell strains resulting from 10 minutes of continuous fluid flow at a flow rate that produces a shear stress of 15 dyne/cm2. Individual cell strains varied widely from less than 1.0% to over 25% strain within the same group of cells. The increased sensitivity of cells to fluid flow induced shear stress may be attributed to much greater cellular deformations resulting from fluid flow induced sheer stress.

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PC208 Subendothelial Matrix-Targeted Liposomal Nanoparticles for Vascular Therapeutics

Journal of Vascular Surgery ◽

10.1016/j.jvs.2017.03.369 ◽

2017 ◽

Vol 65 (6) ◽

pp. 195S-196S

Author(s):

Jonathan S. Cudnik ◽

Michael Best ◽

Stacy S. Kirkpatrick ◽

Michael B. Freeman ◽

Oscar H. Grandas ◽

...

Keyword(s):

Subendothelial Matrix ◽

Liposomal Nanoparticles

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Monocyte adhesion to subendothelial components

Blood ◽

10.1182/blood.v69.4.1265.bloodjournal6941265 ◽

1987 ◽

Vol 69 (4) ◽

pp. 1265-1268

Author(s):

JW Tobias ◽

MM Bern ◽

PA Netland ◽

BR Zetter

Keyword(s):

Cell Line ◽

Human Leukocyte ◽

Adhesion Assay ◽

U937 Cells ◽

Monocyte Adhesion ◽

Active Components ◽

Dot Blot ◽

Collagen Types ◽

Subendothelial Matrix ◽

Soluble Acid

Human monocytes have been shown to penetrate the endothelial layer of large blood vessels and to adhere to the subendothelial basement membrane. To determine the active components of this process, we have studied the ability of monocytes to adhere to isolated components of the subendothelial matrix. Using a quantitative dot-blot adhesion assay, we find that monocytes adhere preferentially to immobilized laminin and elastin. The monocytes adhere less well to fibronectin and bind poorly or not at all to collagen types I and IV, or to heparan sulfate. Monocyte binding to elastin requires an intact, crosslinked molecule as no binding was observed to soluble, acid-alcohol elastin extracts, to pepsin or elastase digests of elastin, to tropoelastin monomer, or to desmosine/isodesmosine crosslinks. Similar binding profiles to elastin, laminin, and fibronectin were seen with the established human leukocyte cell line U937. The promyelocytic cell line HL60 adhered equally well to laminin but showed slightly reduced adhesion to elastin when compared with the fresh monocytes or U937 cells. Freshly isolated human erythrocytes did not demonstrate significant adhesion to fibronectin, laminin, or elastin.

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Subendothelial matrix as the playground for “diabetic milieu” factors in development of angiopathy

Biopolymers and Cell ◽

10.7124/bc.000a30 ◽

2020 ◽

Vol 36 (4) ◽

pp. 245-253

Author(s):

K. A. Nizheradze ◽

A. I. Khoruzhenko

Keyword(s):

Subendothelial Matrix

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Ultrasound Microbubble Treatment Enhances Clathrin-Mediated Endocytosis and Fluid-Phase Uptake through Distinct Mechanisms

10.32920/14638422 ◽

2021 ◽

Author(s):

Farnaz Fekri ◽

Ralph Christian Delos Santos ◽

Raffi Karshafian ◽

Costin N. Antonescu

Keyword(s):

Drug Delivery ◽

Fluid Phase ◽

Acid Sphingomyelinase ◽

Coated Pits ◽

Drug Permeability ◽

Membrane Pores ◽

Signaling Mechanisms ◽

Sheer Stress ◽

Cell Plasma ◽

Fluid Phase Endocytosis

Drug delivery to tumors is limited by several factors, including drug permeability of the target cell plasma membrane. Ultrasound in combination with microbubbles (USMB) is a promising strategy to overcome these limitations. USMB treatment elicits enhanced cellular uptake of materials such as drugs, in part as a result of sheer stress and formation of transient membrane pores. Pores formed upon USMB treatment are rapidly resealed, suggesting that other processes such as enhanced endocytosis may contribute to the enhanced material uptake by cells upon USMB treatment. How USMB regulates endocytic processes remains incompletely understood. Cells constitutively utilize several distinct mechanisms of endocytosis, including clathrin-mediated endocytosis (CME) for the internalization of receptor-bound macromolecules such as Transferrin Receptor (TfR), and distinct mechanism(s) that mediate the majority of fluid-phase endocytosis. Tracking the abundance of TfR on the cell surface and the internalization of its ligand transferrin revealed that USMB acutely enhances the rate of CME. Total internal reflection fluorescence microscopy experiments revealed that USMB treatment altered the assembly of clathrin-coated pits, the basic structural units of CME. In addition, the rate of fluid-phase endocytosis was enhanced, but with delayed onset upon USMB treatment relative to the enhancement of CME, suggesting that the two processes are distinctly regulated by USMB. Indeed, vacuolin-1 or desipramine treatment prevented the enhancement of CME but not of fluid phase endocytosis upon USMB, suggesting that lysosome exocytosis and acid sphingomyelinase, respectively, are required for the regulation of CME but not fluid phase endocytosis upon USMB treatment. These results indicate that USMB enhances both CME and fluid phase endocytosis through distinct signaling mechanisms, and suggest that strategies for potentiating the enhancement of endocytosis upon USMB treatment may improve targeted drug delivery.

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Collagen-dependent platelet dysfunction and its relevance to either mitochondrial ROS or cytosolic superoxide generation: a question about the quality and functional competence of long-stored platelets

10.21203/rs.3.rs-29731/v2 ◽

2020 ◽

Author(s):

Ehteramolsadat Hosseini ◽

Saba Hojjati ◽

Safoora Afzalniaye gashti ◽

Mehran Ghasemzadeh

Keyword(s):

Platelet Adhesion ◽

Oxidant Stress ◽

Ros Generation ◽

Reverse Correlation ◽

Platelet Dysfunction ◽

Mitochondrial Ros ◽

Ros Accumulation ◽

The Matrix ◽

Subendothelial Matrix ◽

Platelet Spreading

Abstract Background: Upon vascular damage, the exposed subendothelial matrix recruits circulating platelets to site of injury while inducing their firm adhesion mainly via GPVI-collagen interaction. GPVI also supports aggregatory and pro-coagulant functions in arterial shear rate even on the matrix other than collagen. Reactive oxygen species (ROS) modulate these stages of thrombosis; however augmented oxidant stress also disturbs platelet functions. Stored-dependent platelet lesion is associated with the increasing levels of ROS. Whether ROS accumulation is also relevant to collagen-dependent platelet dysfunction is the main interest of this study. Methods: Fresh PRP-PCs (platelet concentrates) were either stimulated with potent ROS-inducers PMA and CCCP or stored for 5 days. Intra-platelet superoxide (O2--) or mitochondrial-ROS and GPVI expression were detected by flowcytometery. GPVI shedding, platelet aggregation and spreading/adhesion to collagen were analyzed by western blot, aggregometry and fluorescence-microscopy respectively. Results: Mitochondrial-ROS levels in 5 days-stored PCs were comparable to those induced by mitochondrial uncoupler, CCCP while O2-- generations were higher than those achieved by PMA. Shedding levels in 5 days-stored PCs were higher than those induced by these potent stimuli. GPVI expressions were reduced comparably in CCCP treated and 5 days-stored PCs. Platelet adhesion was also diminished during storage while demonstrating significant reverse correlation with GPVI shedding. However, only firm adhesion (indicated by spreading or platelet adhesion surface area) was relevant to GPVI expression. Platelet adhesion and aggregation also showed reverse correlations with both O2-- and mitochondrial-ROS formations; nonetheless mitochondrial-ROS was only relevant to firm adhesion. Conclusion: As a sensitive indicator of platelet activation, GPVI shedding correlated with either simple adhesion or spreading to collagen, while GPVI expression was only relevant to platelet spreading. Thereby, if the aim of GPVI evaluation is to examine platelet firm adhesion, expression seems to be a more specific choice. Furthermore, the comparable levels of ROS generation in 5 days-stored PCs and CCCP treated platelets, indicated that these products are significantly affected by oxidative stress. Reverse correlation of accumulating ROS with collagen-dependent platelet dysfunction is also a striking sign of an oxidant-induced lesion that may raise serious question about the post-transfusion quality and competence of longer stored products.

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Transport of insulin-like growth factor-I across endothelial cell monolayers and its binding to the subendothelial matrix

Experimental and Clinical Endocrinology & Diabetes ◽

10.1055/s-2002-23488 ◽

2002 ◽

Vol 110 (02) ◽

pp. 67-73 ◽

Cited By ~ 9

Author(s):

J. Grulich-Henn ◽

J. Ritter ◽

S. Mesewinkel ◽

U. Heinrich ◽

M. Bettendorf ◽

...

Keyword(s):

Endothelial Cell ◽

Growth Factor ◽

Insulin Like Growth Factor ◽

Cell Monolayers ◽

Factor I ◽

Subendothelial Matrix ◽

Growth Factor I

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Abstract 16504: Low Disturbed Flow Induces Dynamic Immune Compartment Alterations in Atherogenesis as Revealed by Single Cell Rna-seq

Circulation ◽

10.1161/circ.142.suppl_3.16504 ◽

2020 ◽

Vol 142 (Suppl_3) ◽

Author(s):

Lili Qu ◽

Chuan Li ◽

Alyssa Matz ◽

Annabelle Rodriguez-Oquendo ◽

Anthony Vella ◽

...

Keyword(s):

Immune Cell ◽

Paired Comparison ◽

Cell Types ◽

Cell Interaction ◽

Artery Ligation ◽

Human Artery ◽

Disturbed Flow ◽

Signature Genes ◽

Sheer Stress ◽

The Impact

Low disturbed blood flow (LDF) is a critical contributing factor to atherogenesis but its direct impact on the immune compartment was not well-depict. To fill this knowledge gap, we adopted scRNA-seq to capture sheer-stress induced immune responses during atherogenesis. A partial carotid artery ligation (PCAL) model was selected for its paired comparison of carotid arteries with normal flow (NF) or LDF. Indeed, we observed drastic changes in both endothelial and immune compartment. Macrophages were the most significantly increased population induced by LDF (from 4% to 12% of CD45+ cells) with two well-separated subsets (Mac-c8, Mac-c9). MacSpectrum analyses revealed that Mac-c8 displayed higher inflammatory states than the lipid-laden Mac-c9. Interestingly, three T subtypes displayed unique flow-induced enrichment patterns that were selectively enriched in LDF but not in the NF condition. Furthermore, we created an original algorithms to evaluate the impact of sheer-stress on membrane protein-mediated cell-cell interaction among all cell types in the atheroma. Several pairs of molecular interactions were identified, including multiple APP-ligands interaction pairs and those in BAG2 Signaling. Moreover, signature genes identified in these LDF-induced T cells displayed high correlation to the plaque severity in human artery-aorta samples. Collectively, our study provided a high-resolution and focused analyses of sheer-stress induced immune cell action during atherogenesis. This is also the first identification of unique T subsets, to our knowledge, that are enriched in arterial wall exposed to low and disturbed flow. Further characterization of these cells will provide valuable information to understand and therapeutically treat atherogenesis.

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Abstract 15949: High Intensity Interval Training is Superior to Continuous Training and Reverses RV Remodeling and Dysfunction in a Rat Model of Pulmonary Hypertension

Circulation ◽

10.1161/circ.132.suppl_3.15949 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Mary Beth Brown ◽

Evandro Neves ◽

Rachel Novack ◽

Amanda Fisher ◽

Robert Presson ◽

...

Keyword(s):

Rat Model ◽

High Intensity ◽

Systolic Pressure ◽

Interval Training ◽

Wall Stress ◽

High Intensity Interval Training ◽

Sprague Dawley ◽

Continuous Training ◽

Sheer Stress ◽

High Intensity Interval

Exercise appears to have overall benefit in pulmonary arterial hypertension (PAH); however, studies to date indicate little effect on the elevated pulmonary pressure or RV hypertrophy (RVH) and dysfunction associated with the disease. High intensity interval training (HIIT) is reported to be superior to the more customary prolonged continuous exercise training (CExT) protocol for chronic heart failure but has not been tested for PAH. Therefore, we investigated impact of a 6 wk HIIT vs. CExT treadmill program in a monocrotaline rat model of mild PAH (MCT, 40 mg/kg) on indicators of disease progression. Methods: Treadmill training was performed 5x/wk in male Sprague-Dawley MCT rats (250-300g), following a protocol of either HIIT (5 cycles of 2 min at ~90% VO 2 reserve [VO 2 R] + 3 min at 30% VO 2 R; n=8), or low intensity CExT (60 min at 50% VO 2 R; n=7). Statistical analysis was performed by one-way ANOVA. Results: MCT-induced decrements in VO 2 max were ameliorated by both HIIT and CExT (p < 0.01 vs. sedentary MCT rats, MCT-SED, n=6), and were similar to healthy controls (CON, n=6). Most importantly, RV systolic pressure (RVSP, in mmHg; via Millar catheter) and RVH (ratio of RV to LV+S mass) were lowered (p<0.05) only by HIIT (28.7±2, and 0.32±0.02) and not by CExT (44.1±3, and 0.43±0.01) vs. MCT-SED (40.2±3.2, and 0.41±0.02). Cardiac output (Δ from baseline in μl, via RV echocardiography) was also improved by HIIT (117±28) vs. MCT-SED (6±42, p=0.04). Additional hemodynamic recordings during running, via novel implantable telemetry (DSI), were obtained serially at pre- and 2, 4, 6, and 8 wks post-MCT, and revealed ‘surges’ in RVSP during HIIT, vs. a steady RVSP pattern during CExT. Pulmonary eNOS (per immunoblotting) was increased (p<0.05) with HIIT, consistent with greater endothelial stimulation. Conclusions: HIIT is superior to CExT for improving hemodynamics and RV remodeling and dysfunction in MCT rats and warrants further investigation in other models and in patients. More favorable outcomes may be explained by greater sheer-stress mediated vascular endothelial adaptation to HIIT stimulus, or lower cumulative training-induced RV wall stress with the briefer HIIT session duration.

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