Process Of Endocytosis Research Articles

Novel Silybin-Conjugated Chitosan Polymeric Micelles for Improving the Oral Absorption of Doxorubicin Based on the Inhibition of P-gp and CYP3A4.

A drug delivery system based on silybin-conjugated chitosan (CS-SB) polymeric micelles was developed to improve the oral absorption of doxorubicin (DOX). SB was grafted to CS via succinic acid, and CS-SB was identified by 1H NMR and FT-IR. The DOX-loaded micelles were prepared by self-assembly, and the characteristics of micelles, including a small particle size of 167.8 ± 2.3 nm, a high drug loading capacity of 8.59%, and a low critical micelle concentration of 1.3 × 10-5 g/mL, were demonstrated. The micelles showed oral bioavailability of up to 193% versus DOX·HCl. The cytotoxicity test showed the biosafety of CS-SB and the potential of reductive DOX-induced cardiotoxicity. The inhibition of P-gp efflux and CYP3A4 enzyme in CS-SB micelles was confirmed by cellular uptake and enzyme activity inhibition tests. The endocytosis process of micelles was revealed by an endocytosis inhibition test. The findings exhibited the potential of CS-SB micelles in drug delivery.

Characterization of atypical BAR domain-containing proteins coded by Toxoplasma gondii

Toxoplasma gondii, the causative agent of toxoplasmosis, infects cells and replicates inside via the secretion of factors stored in specialized organelles (rhoptries, micronemes, dense granules) and the capture of host materials. The genesis of the secretory organelles and the processes of secretion and endocytosis depend on vesicular trafficking events whose molecular bases remain poorly known. Notably, there is no characterization of the BAR (Bin/Amphiphysin/Rvs) domain-containing proteins expressed by T. gondii and other apicomplexans, although such proteins are known to play critical roles in vesicular trafficking in other eukaryotes. Here, by combining structural analyses with in vitro assays and cellular observations, we have characterized TgREMIND (REgulators of Membrane Interacting Domains), involved in the genesis of rhoptries and dense granules, and TgBAR2 found at the parasite cortex. We establish that TgREMIND comprises an F-BAR domain that can bind curved neutral membranes with no strict phosphoinositide requirement and exert a membrane remodeling activity. Next, we establish that TgREMIND contains a new structural domain called REMIND, which negatively regulates the membrane-binding capacities of the F-BAR domain. In parallel, we report that TgBAR2 contains a BAR domain with an extremely basic membrane-binding interface able to deform anionic membranes into very narrow tubules. Our data show that T. gondii codes for two atypical BAR domain-containing proteins with very contrasting membrane-binding properties, allowing them to function in two distinct regions of the parasite trafficking system.

Oral delivery of solid lipid nanoparticles surface decorated with hyaluronic acid and bovine serum albumin: A novel approach to treat colon cancer through active targeting

The present study aims to prepare and evaluate solid lipid nanoparticles (SLNs) loaded with irinotecan (IRN) drug and daidzein (DZN) isoflavonoid and surface coated with ligand materials such as hyaluronic acid (HA) and bovine serum albumin (BSA) with additional coating of chitosan for active targeting to receptors present on colon surface epithelium for oral targeted delivery. The optimized batch was evaluated for particle size, zeta potential exhibiting nanometric size with good entrapment efficiency. Nanoparticles were found to be spherical. FTIR and DSC revealed that all the excipients and formulation were compatabile to each other and showed better encapsulation exhibiting amorphous and crystallinity forms. In vitro drug release of SLNs confirmed that initially a burst release, followed by sustained release pattern was exhibited. Cell lines studied performed on HT-29 cells showed demonstrated that conjugated SLNs inhibited cytotoxicity at 75 μg/ml, indicating that cells were taken up through a receptor-mediated endocytosis process. Cell cycle analysis showed that cell arrest was done at 67.8 % (G0/G1 phase) and inhibited apoptosis by 56 %. Further during In vivo studies, RT-PCR study revealed downregulation of Carcinoembryonic antigen (CEA), a non-specific serum biomarker overexpressed in tumor cells and upregulation of pro-inflammatory cytokine TNF-α. Histopathological study revealed that conjugated (HA-BSA) coated with chitosan SLNs restored normal mucosa and colon architecture, depicting all mucosal layers. Hence, these conjugated SLNs may serve as a novel combination for the treatment of colon cancer.

Membrane trafficking of synaptic adhesion molecules.

Synapse formation and stabilization are aided by several families of adhesion molecules, which are generally seen as specialized surface receptors. The function of most surface receptors, including adhesion molecules, is modulated in non-neuronal cells by the processes of endocytosis and recycling, which control the number of active receptors found on the cell surface. These processes have not been investigated extensively at the synapse. This review focuses on the current status of this topic, summarizing general findings on the membrane trafficking of the most prominent synaptic adhesion molecules. Remarkably, evidence for endocytosis processes has been obtained for many synaptic adhesion proteins, including dystroglycans, latrophilins, calsyntenins, netrins, teneurins, neurexins, neuroligins and neuronal pentraxins. Less evidence has been obtained on their recycling, possibly because of the lack of specific assays. We conclude that the trafficking of the synaptic adhesion molecules is an important topic, which should receive more attention in the future.

Endocytosis of Synaptic Vesicle in Motor Nerve Endings of FUS Transgenic Mice with a Model of Amyotrophic Lateral Sclerosis.

In experiments on the motor nerve endings of the diaphragm of transgenic FUS mice with a model of amyotrophic lateral sclerosis at the pre-symptomatic stage of the disease, the processes of transmitter release and endocytosis of synaptic vesicles were studied. In FUS mice, the intensity of transmitter release during high-frequency stimulation of the motor nerve (50 imp/sec) was lowered. At the same duration of stimulation, the loading of fluorescent dye FM1-43 was lower in FUS mice. However, at the time of stimulation, during which an equal number of quanta are released in wild-type and FUS mice, no differences in the intensity of dye loading were found. Thus, endocytosis is not the key factor in the mechanism of synaptic dysfunction in FUS mice at the pre-symptomatic stage.

Pik3c3 expression profiling in the mouse kidney and its role in proximal tubule cell physiology.

The class 3 phosphatidylinositol 3-kinase (Pik3c3) plays critical roles in regulating autophagy, endocytosis, and nutrient sensing, but its expression profile in the kidney remains undefined. Recently, we validated a Pik3c3 antibody through immunofluorescence staining of kidney tissues from cell type-specific Pik3c3 knockout mice. Immunohistochemistry unveiled significant disparities in Pik3c3 expression levels across various kidney cell types. Notably, renal interstitial cells exhibit minimal Pik3c3 expression. Further, coimmunofluorescence staining, utilizing nephron segment- or cell type-specific markers, revealed nearly undetectable levels of Pik3c3 expression in glomerular mesangial cells and endothelial cells. Intriguingly, although podocytes exhibit the highest Pik3c3 expression levels among all kidney cell types, the renal proximal tubule cells (RPTCs) express the highest level of Pik3c3 among all renal tubules. RPTCs are known to express the highest level of the epidermal growth factor receptor (EGFR) in adult kidneys; however, the role of Pik3c3 in EGFR signaling within RPTCs remains unexplored. Therefore, we conducted additional cell culture studies. The results demonstrated that Pik3c3 inhibition significantly delayed EGF-stimulated EGFR degradation and the termination of EGFR signaling in RPTCs. Mechanistically, Pik3c3 inhibition surprisingly did not affect the initial endocytosis process but instead impeded the lysosomal degradation of EGFR. In summary, this study defines, for the first time, the expression profile of Pik3c3 in the mouse kidney and also highlights a pivotal role of Pik3c3 in the proximal tubule cells. These findings shed light on the intricate mechanisms underlying Pik3c3-mediated regulation of EGFR signaling, providing valuable insights into the role of Pik3c3 in renal cell physiology. NEW & NOTEWORTHY This is the first report defining the class 3 phosphatidylinositol 3-kinase (Pik3c3) expression profile in the kidney. Pik3c3 is nearly absent in renal interstitial cells, glomerular mesangial cells, and endothelial cells. Remarkably, glomerular podocytes express the highest Pik3c3 level in the kidney. However, the proximal tubule exhibits the highest expression level among all renal tubules. This study also unveils the pivotal role of Pik3c3 in regulating EGFR degradation and signaling termination in RPTCs, furthering our understanding of Pik3c3 in renal cell physiology.

Toxicological effects, absorption and biodegradation of bisphenols with different functional groups in Chromochloris zofingiensis

Bisphenols (BPs) are recognized as endocrine disrupting compounds and have garnered increasing attention due to their widespread utilization. However, the varying biological toxicities and underlying mechanisms of BPs with different functional groups remain unknown. In the present study, the toxic effects of four BPs (BPA, BPS, BPAF, and TBBPA) on a photosynthetic microalgae Chromochloris zofingiensis were compared. Results showed that halogen-containing BPs exhibited higher cellular uptake, leading to more severe oxidative stress, lower photosynthetic efficiency, and greater accumulation of starch and lipids. Specifically, TBBPA with bromine groups showed a greater toxicity than BPAF with fluorine groups, possibly due to the incomplete debromination in C. zofingiensis. Transcriptomic analysis revealed that halogen-containing BPs triggered greater number of differentially expressed genes (DEGs), and only 64 common DEGs were found among different BPs, indicating that the effects of BPs with different functional groups varied greatly. Genes involved in endocytosis, peroxisomes, and endoplasmic reticulum protein processing pathways were mostly upregulated across different BPs, while photosynthesis-related genes showed varied expression, possibly due to their distinct functional groups. Additionally, SIN3A, ZFP36L, CHMP, and ATF2 emerged as potential key regulatory genes. Overall, this study thoroughly explained how functional groups impact the toxicity and biodegradation of BPs in C. zofingiensis.

Improving treatment for Parkinson's disease: Harnessing photothermal and phagocytosis-driven delivery of levodopa nanocarriers across the blood-brain barrier

Parkinson's disease (PD) poses a significant therapeutic challenge, mainly due to the limited ability of drugs to cross the blood-brain barrier (BBB) without undergoing metabolic transformations. Levodopa, a key component of dopamine replacement therapy, effectively enhances dopaminergic activity. However, it encounters obstacles from peripheral decarboxylase, hindering its passage through the BBB. Furthermore, levodopa metabolism generates reactive oxygen species (ROS), exacerbating neuronal damage. Systemic pulsatile dosing further disrupts natural physiological buffering mechanisms. In this investigation, we devised a ROS-responsive levodopa prodrug system capable of releasing the drug and reducing ROS levels in the central nervous system. The prodrug was incorporated within second near-infrared region (NIR-II) gold nanorods (AuNRs) and utilized angiopep-2 (ANG) for targeted delivery across the BBB. The processes of tight junction opening and endocytosis facilitated improved levodopa transport. ROS scavenging helped alleviate neuronal oxidative stress, leading to enhanced behavioral outcomes and reduced oxidative stress levels in a mouse model of PD. Following treatment, the PD mouse model exhibited enhanced flexibility, balance, and spontaneous exploratory activity. This approach successfully alleviated the motor impairments associated with the disease model. Consequently, our strategy, utilizing NIR-Ⅱ AuNRs and ANG-mediated BBB penetration, coupled with the responsive release of levodopa, offers a promising approach for dopamine supplementation and microenvironmental regulation. This system holds substantial potential as an efficient platform for delivering neuroprotective drugs and advancing PD therapy.

Nonequilibrium Dynamic Phase Diagram for Transmembrane Transport of Active Particles.

In recent years, there has been considerable push toward the biomedical applications with active particles, which have great potential to revolutionize disease diagnostics and therapy. The direct penetration of active particles through the cell membrane leads to more efficient intracellular delivery than previously considered endocytosis processes but may cause membrane disruption. Understanding fundamental behaviors of cell membranes in response to such extreme impacts by active particles is crucial to develop active particle-based biomedical technologies and manage health and safety issues in this emerging field. Unfortunately, the physical principles underlying the nonequilibrium behaviors from endocytosis to direct penetration remain elusive, and experiments are challenging. Here, we present a computed dynamic phase diagram for transmembrane transport of active particles and identify four characteristic dynamic phases in endocytosis and direct penetration according to the particle activity and membrane tension. The boundaries dividing these phases are analytically obtained with theoretical models, elucidating the nonequilibrium physics and criteria for the transition between different phases. Furthermore, we numerically and experimentally show three distinct dynamic regimes related to the interplay between necking and wrapping during the endocytosis process of active particles, which strikingly contrast the regimes for passive particles. Overall, these findings could be useful for sharpening the understanding of basic principles underlying biological issues related to the safe and efficient biomedical applications of such emerging matters.

(Invited) An in Vitro Model of Mechanical Strain Enhances Cellular Uptake of Single-Walled Carbon Nanotubes

Single-walled carbon nanotubes (SWCNTs) are ideal optical biosensors due to their intrinsic near-infrared (NIR) emission, which is highly sensitive, easily tunable, and indefinitely photostable. Due to such desirable properties coupled with appropriate functionalization strategies, SWCNTs have been used in numerous in vitro, live-cell, and in vivo applications. Depending on the type of functionalization as well as cell type, SWCNTs can be internalized by live cells via demonstrated energy-dependent endocytosis processes where they are retained within the endosomal pathway or are expelled by the cells. While this uptake and intracellular processing of SWCNTs has been recently examined, these studies are usually performed with standard cell culture techniques in petri dishes or 3D cultures. Unlike these cultures, cells in living organisms are continuously exposed to a wide variety of stimuli, e.g., periodic mechanical strain, during both normal and disease-related conditions. Thus, it is important to investigate how cells under physiological stretching compare to those grown in standard cultures. Herein, using a novel cell stretching platform to mimic physiological conditions, we investigate the uptake of SWCNTs into different human cancer cells.Our results indicate that cells exposed to uniform radial stretching display significantly higher rates of nanoparticle uptake, which can be correlated to their increased level of cellular activity. This approach recognizes the importance of studying cellular responses in environments that more closely resemble the complex conditions found in living organisms. It suggests a potential connection between mechanical stimuli and cellular processes related to SWCNT uptake. This finding has implications for understanding how nanotube uptake differs in different cellular stress environments and how cells respond to their dynamic and ever-changing microenvironment.Investigating how the mechanical strain influences the endocytosis processes and subsequent intracellular fate of SWCNTs can provide valuable insights into the interplay between nanomaterials and living cells under more realistic conditions. Further aiding us in the development of more accurate intracellular biosensors and effective drug delivery platforms using SWCNTs.

Computational design of an Au nanohexapod shape for internalization into an idealized plasma membrane, investigating sizes, shapes, and modified surfaces

Computational microscopy is a crucial tool for studying internalization of Au nanohexapods (AuNHs) and can be applied in designing nanostructures for biomedical applications. To further explore the molecular insights into interactions between AuNHs and a plasma membrane (PM), we conducted a coarse-grained molecular dynamic (CGMD) simulation. This simulation aimed to investigate the cellular internalization pathways of AuNHs, considering factors such as sizes (6, 8, 10, and 12 nm diameters) varying rod lengths (LR_S0.6) and spheres at end edges (LR_S0.9), shapes (varying sphere diameters (DS) end edges, and varying pyramid cores (DC) for fixed size at 8 nm AuNH), and surface-charge modifications (neutral and negatively charged). The simulation results indicated that size, shape, and surface modification significantly affect cellular uptake. Each AuNH size facilitated interaction and translocation through the PM by direct permeation and an endocytosis process, utilizing sharp ends or edges to disrupt/penetrate the PM and subsequently enter the inner cell. Direct translocations of shapes (DS and DC AuNHs) were not observed. The surface-charged modification (8 nm sized AuNHs) showed the direct translocation process. When comparing the cellular uptake of shaped AuNHs, the DC AuNH exhibited a higher free-energy barrier. Notably, anionic AuNHs demonstrated the lowest free-energy barrier among the various surface-charged AuNHs compared with neutrally charged AuNHs and bare AuNHs, resulting in anionic charges that were more easily translocated into the inner cell than other shapes and charges. Additionally, the permeability of the surface covering was lower than the unmodified surface due to charges and hydrocarbons facilitating translocation. These findings offer a comprehensive understanding of interactions between AuNHs with various characteristics and a realistic PM, thereby providing insights for the design of nanostructures with biological applications.

Combination of spironolactone and DPP-4 inhibitors for treatment of SARS-CoV-2 infection: a literature review.

Coronavirus disease 2019 (COVID-19) is still causing hospitalization and death, and vaccination appears to become less effective with each emerging variant. Spike, non-spike, and other possible unrecognized mutations have reduced the efficacy of recommended therapeutic approaches, including monoclonal antibodies, plasma transfusion, and antivirals. SARS-CoV-2 binds to angiotensin-converting enzyme 2 (ACE2) and probably dipeptidyl peptidase 4 (DPP-4) to initiate the process of endocytosis by employing host proteases such as transmembrane serine protease-2 (TMPRSS-2) and ADAM metallopeptidase domain 17 (ADAM17). Spironolactone reduces the amount of soluble ACE2 and antagonizes TMPRSS-2 and ADAM17. DPP-4 inhibitors play immunomodulatory roles and may block viral entry. The efficacy of treatment with a combination of spironolactone and DPP-4 inhibitors does not appear to be affected by viral mutations. Therefore, the combination of spironolactone and DPP-4 inhibitors might improve the clinical outcome for COVID-19 patients by decreasing the efficiency of SARS-CoV-2 entry into cells and providing better anti-inflammatory, antiproliferative, and antifibrotic effects than those achieved using current therapeutic approaches such as antivirals and monoclonal antibodies.

Vesicle and reaction-diffusion hybrid modeling with STEPS

Vesicles carry out many essential functions within cells through the processes of endocytosis, exocytosis, and passive and active transport. This includes transporting and delivering molecules between different parts of the cell, and storing and releasing neurotransmitters in neurons. To date, computational simulation of these key biological players has been rather limited and has not advanced at the same pace as other aspects of cell modeling, restricting the realism of computational models. We describe a general vesicle modeling tool that has been designed for wide application to a variety of cell models, implemented within our software STochastic Engine for Pathway Simulation (STEPS), a stochastic reaction-diffusion simulator that supports realistic reconstructions of cell tissue in tetrahedral meshes. The implementation is validated in an extensive test suite, parallel performance is demonstrated in a realistic synaptic bouton model, and example models are visualized in a Blender extension module.

The Plasma Membrane and Mechanoregulation in Cells.

Cells inhabit a mechanical microenvironment that they continuously sense and adapt to. The plasma membrane (PM), serving as the boundary of the cell, plays a pivotal role in this process of adaptation. In this Review, we begin by examining well-studied processes where mechanoregulation proves significant. Specifically, we highlight examples from the immune system and stem cells, besides discussing processes involving fibroblasts and other cell types. Subsequently, we discuss the common molecular players that facilitate the sensing of the mechanical signal and transform it into a chemical response covering integrins YAP/TAZ and Piezo. We then review how this understanding of molecular elements is leveraged in drug discovery and tissue engineering alongside a discussion of the methodologies used to measure mechanical properties. Focusing on the processes of endocytosis, we discuss how cells may respond to altered membrane mechanics using endo- and exocytosis. Through the process of depleting/adding the membrane area, these could also impact membrane mechanics. We compare pathways from studies illustrating the involvement of endocytosis in mechanoregulation, including clathrin-mediated endocytosis (CME) and the CLIC/GEEC (CG) pathway as central examples. Lastly, we review studies on cell-cell fusion during myogenesis, the mechanical integrity of muscle fibers, and the reported and anticipated roles of various molecular players and processes like endocytosis, thereby emphasizing the significance of mechanoregulation at the PM.

A Quantitative Method to Distinguish Cytosolic from Endosome-Trapped Cell-Penetrating Peptides.

Cell-penetrating peptides are known to penetrate cells through endocytosis and translocation. The two pathways are hardly distinguished in current cell assays. We developed a reliable, simple and robust method to distinguish and quantify independently the two routes. The assay requires (DABCYL) 4-(dimethylaminoazo)benzene-4-carboxylic acid- and (CF) carboxyfluorescein-labeled peptides. When the labeled peptide is intact, the fluorescence signal is weak thanks to the dark quenching property of DABCYL. A 10-fold higher fluorescence signal is measured when the labeled peptide is degraded. By referring to a standard fluorescent curve according to the concentration of the hydrolyzed peptide, we have access to the internalized peptide quantity. Therefore, cell lysis after internalization permits to determine the total quantity of intracellular peptide. The molecular state of the internalized peptide (intact or degraded), depends on its location in cells (cytosol vs endo-lysosomes), and can be blocked by boiling cells. This boiling step results indeed in denaturation and inhibition of the cellular enzymes. The advantage of this method is the possibility to quantify translocation at 37 °C and to compare it to the 4 °C condition, where all endocytosis processes are inhibited. We found that ranking of the translocation efficacy is DABCYL-R6-(ϵCF)K≫DABCYL-R4-(ϵCF)K≥CF-R9.

A high-throughput screen in mESCs to identify the cross-talk between signaling, endocytosis, and pluripotency.

Embryonic stem cell fate is regulated by various cellular processes. Recently, the process of endocytosis has been implicated in playing a role in the maintenance of self-renewal and pluripotency of mouse embryonic stem cells. A previous siRNA-based screen interrogated the function of core components of the endocytic machinery in maintaining the pluripotency of embryonic stem cells, revealing a crucial role for clathrin mediated endocytosis. A number of other proteins involved in key signaling pathways have also been shown to both regulate and be regulated by endocytosis. We collated a list of 1141 genes in connection to the term "endocytosis" from Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO), excluding those previously interrogated, and examined the effect of their knockdown on the pluripotency of mouse embryonic stem cells (mESCs) using levels of green fluorescent protein driven by the Oct4 promoter. We used high-throughput screening followed by an automatedMATrix LABoratory(MATLAB)-based analysis pipeline and assessed changes in GFP fluorescence as a readout for ESC pluripotency. Through this screen we identified a number of genes, many hitherto not associated with stem cell pluripotency, which upon knockdown either resulted in a significant increase or decrease of GFP fluorescence. We further present validation for some of these hits. We present a workflow aimed to identify genes involved in signaling pathways which can be regulated by endocytosis, and that affect the pluripotency of ESCs.

The EH domain-containing protein, EdeA, is involved in endocytosis, cell wall integrity, and pathogenicity in Aspergillus fumigatus.

Aspergillus fumigatus is a significant human pathogenic fungus known to cause invasive aspergillosis, a disease with a high mortality rate. Understanding the basic principles of A. fumigatus pathogenicity is crucial for developing effective strategies against this pathogen. Previous research has underscored the importance of endocytosis in the infection capacity of pathogenic yeasts; however, its biological function in pathogenic mold remains largely unexplored. Our characterization of EdeA in A. fumigatus sheds light on the role of endocytosis in the development, stress response, and pathogenicity of pathogenic molds. These findings suggest that the components of the endocytosis process may serve as potential targets for antifungal therapy.

Oxidative stress, defective proteostasis and immunometabolic complications in critically ill patients.

Oxidative stress (OS) develops in critically ill patients as a metabolic consequence of the immunoinflammatory and degenerative processes of the tissues. These induce increased and/or dysregulated fluxes of reactive species enhancing their pro-oxidant activity and toxicity. At the same time, OS sustains its own inflammatory and immunometabolic pathogenesis, leading to a pervasive and vitious cycle of events that contribute to defective immunity, organ dysfunction and poor prognosis. Protein damage is a key player of these OS effects; it generates increased levels of protein oxidation products and misfolded proteins in both the cellular and extracellular environment, and contributes to forms DAMPs and other proteinaceous material to be removed by endocytosis and proteostasis processes of different cell types, as endothelial cells, tissue resident monocytes-macrophages and peripheral immune cells. An excess of OS and protein damage in critical illness can overwhelm such cellular processes ultimately interfering with systemic proteostasis, and consequently with innate immunity and cell death pathways of the tissues thus sustaining organ dysfunction mechanisms. Extracorporeal therapies based on biocompatible/bioactive membranes and new adsorption techniques may hold some potential in reducing the impact of OS on the defective proteostasis of patients with critical illness. These can help neutralizing reactive and toxic species, also removing solutes in a wide spectrum of molecular weights thus improving proteostasis and its immunometabolic corelates. Pharmacological therapy is also moving steps forward which could help to enhance the efficacy of extracorporeal treatments. This narrative review article explores the aspects behind the origin and pathogenic role of OS in intensive care and critically ill patients, with a focus on protein damage as a cause of impaired systemic proteostasis and immune dysfunction in critical illness.

Biomechanics-mediated endocytosis in atherosclerosis.

Biomechanical forces, including vascular shear stress, cyclic stretching, and extracellular matrix stiffness, which influence mechanosensitive channels in the plasma membrane, determine cell function in atherosclerosis. Being highly associated with the formation of atherosclerotic plaques, endocytosis is the key point in molecule and macromolecule trafficking, which plays an important role in lipid transportation. The process of endocytosis relies on the mobility and tension of the plasma membrane, which is sensitive to biomechanical forces. Several studies have advanced the signal transduction between endocytosis and biomechanics to elaborate the developmental role of atherosclerosis. Meanwhile, increased plaque growth also results in changes in the structure, composition and morphology of the coronary artery that contribute to the alteration of arterial biomechanics. These cross-links of biomechanics and endocytosis in atherosclerotic plaques play an important role in cell function, such as cell phenotype switching, foam cell formation, and lipoprotein transportation. We propose that biomechanical force activates the endocytosis of vascular cells and plays an important role in the development of atherosclerosis.

Coupling of nanostraws with diverse physicochemical perforation strategies for intracellular DNA delivery

Effective intracellular DNA transfection is imperative for cell-based therapy and gene therapy. Conventional gene transfection methods, including biochemical carriers, physical electroporation and microinjection, face challenges such as cell type dependency, low efficiency, safety concerns, and technical complexity. Nanoneedle arrays have emerged as a promising avenue for improving cellular nucleic acid delivery through direct penetration of the cell membrane, bypassing endocytosis and endosome escape processes. Nanostraws (NS), characterized by their hollow tubular structure, offer the advantage of flexible solution delivery compared to solid nanoneedles. However, NS struggle to stably self-penetrate the cell membrane, resulting in limited delivery efficiency. Coupling with extra physiochemical perforation strategies is a viable approach to improve their performance. This study systematically compared the efficiency of NS coupled with polyethylenimine (PEI) chemical modification, mechanical force, photothermal effect, and electric field on cell membrane perforation and DNA transfection. The results indicate that coupling NS with PEI modification, mechanical force, photothermal effects provide limited enhancement effects. In contrast, NS-electric field coupling significantly improves intracellular DNA transfection efficiency. This work demonstrates that NS serve as a versatile platform capable of integrating various physicochemical strategies, while electric field coupling stands out as a form worthy of primary consideration for efficient DNA transfection.