Lipid Bilayer Vesicles Research Articles

Efficient Loading into and Controlled Release of Lipophilic Compound from Liposomes by Using Cyclodextrin as Novel Trapping Agent.

Lipid bilayer vesicles, liposomes are representative drug delivery carriers. High encapsulation efficiency and release control of drugs are essential for clinical application of liposomes. For efficient drug loading into liposomes, remote loading method using driving force like transmembrane gradients of pH and ions are utilized. Ions are called as "trapping agents," which are also critical for the controlled release of drugs loaded into liposomes inside. It is difficult to apply ions as trapping agents to various drugs because of limited physicochemical compatibility between drugs and ions. Cyclodextrins (CDs) with hydrophobic cavity can make inclusion complexes with various hydrophobic compounds. Therefore, we aimed to evaluate the potential of CDs as a novel trapping agent using sulfobutylether-β-cyclodextrin (SBE-β-CD) and ibuprofen (IB), a weak acid hydrophobic drug. Encapsulation efficiency of IB in liposomes with pH gradient was approximately 27%, and it was enhanced by intraliposomal SBE-β-CD inclusion in addition to pH gradient, which was SBE-β-CD concentration-dependent. In liposomes with pH gradient, a large fraction of IB was released in a short time. This early-stage rapid IB release was significantly suppressed by the inclusion of SBE-β-CD inside liposomes. Thus, novel remote loading technology by intraliposomal SBE-β-CD enabled the efficient encapsulation of the hydrophobic drug into the aqueous phase of liposomes as well as their controlled release. This technology should be applied to various drugs that can be included into CDs in order to enhance their therapeutic benefits.

Rotaxanes with a photoresponsive macrocycle modulate the lipid bilayers of large and giant unilamellar vesicles

Rotaxanes equipped with actuators hold great potential for developing highly functional molecular machines. Such systems could significantly enhance our ability to study and manipulate biological and artificial membranes. Here, we introduce a rotaxane with a ring featuring two azobenzene photoswitches, which retain their photoreversibility and can be stochastically shuttled along the axle in solution. Studies in model bilayers, supported by molecular dynamics simulations, show how azobenzene photoswitching alters the interaction of rotaxanes with surrounding lipids, leading to changes in lipid packing. Such changes in the lipid bilayer were leveraged to induce the light-triggered release of sulforhodamine B from large unilamellar vesicles. Additionally, light activation of the rotaxanes is shown to induce reversible contraction and expansion of giant unilamellar vesicles. The results provide novel insights into the interactions and operation of rotaxanes in lipid bilayers and their impact on membrane properties. This will aid in developing systems for precise membrane manipulation for applications in biomedicine and bioengineering.

A small-molecule carrier for the intracellular delivery of a membrane-impermeable protein with retained bioactivity.

Intracellular protein delivery has the potential to revolutionize cell-biological research and medicinal therapy, with broad applications in bioimaging, disease treatment, and genome editing. Herein, we demonstrate successful delivery of a functional protein, cytochrome c (CYC), by using a boron cluster anion as molecular carrier of the superchaotropic anion type (B12Br11OPr2-). CYC was delivered into lipid bilayer vesicles as well as living cells, with a cellular uptake ratio approaching 90%. Mechanistic studies showed that CYC was internalized into cells through a permeation pathway directly into the cytoplasm, bypassing endosomal entrapment. Upon carrier-assisted internalization, CYC retained its bioactivity, as reflected by an induced cell apoptosis rate of 25% at low dose (1 µM). This study furbishes a direct protein delivery method by a molecular carrier with high efficiency, confirming the potential of inorganic cluster ions as protein transport vehicles with an extensive range of future cell-biological or biomedical applications.

Role of Exosomes in Salivary Gland Tumors and Technological Advances in Their Assessment.

Backgroud: Salivary gland tumors (SGTs) are rare and diverse neoplasms, presenting significant challenges in diagnosis and management due to their rarity and complexity. Exosomes, lipid bilayer vesicles secreted by almost all cell types and present in all body fluids, have emerged as crucial intercellular communication agents. They play multifaceted roles in tumor biology, including modulating the tumor microenvironment, promoting metastasis, and influencing immune responses. Results: This review focuses on the role of exosomes in SGT, hypothesizing that novel diagnostic and therapeutic approaches can be developed by exploring the mechanisms through which exosomes influence tumor occurrence and progression. By understanding these mechanisms, we can leverage exosomes as diagnostic and prognostic biomarkers, and target them for therapeutic interventions. The exploration of exosome-mediated pathways contributing to tumor progression and metastasis could lead to more effective treatments, transforming the management of SGT and improving patient outcomes. Ongoing research aims to elucidate the specific cargo and signaling pathways involved in exosome-mediated tumorigenesis and to develop standardized techniques for exosome-based liquid biopsies in clinical settings. Conclusions: Exosome-based liquid biopsies have shown promise as non-invasive, real-time systemic profiling tools for tumor diagnostics and prognosis, offering significant potential for enhancing patient care through precision and personalized medicine. Methods like fluorescence, electrochemical, colorimetric, and surface plasmon resonance (SPR) biosensors, combined with artificial intelligence, improve exosome analysis, providing rapid, precise, and clinically valid cancer diagnostics for difficult-to-diagnose cancers.

Extracellular vesicles affecting embryo development in vitro: a potential culture medium supplement.

Extracellular vesicles (EVs) are nanometer-sized lipid bilayer vesicles released by cells, playing a crucial role in mediating cellular communication. This review evaluates the effect of EVs on early embryonic development in vitro by systematically searching the literature across three databases, Embase, PubMed, and Scopus, from inception (Embase, 1947; PubMed, 1996; and Scopus, 2004) to 30 June 2024. A total of 28 studies were considered relevant and included in this review. The EVs included in these investigations have been recovered from a range of sources, including oviduct fluid, follicular fluid, uterine fluid, seminal plasma, embryos, oviduct epithelial cells, endometrial epithelial cells, amniotic cells, and endometrial-derived mesenchymal stem cells collected primarily from mice, rabbits, cattle and pigs. This diversity in EV sources highlights the broad interest and potential applications of EVs in embryo culture systems. These studies have demonstrated that supplementation with EVs derived from physiologically normal biofluids and cells to the embryo culture medium system has positive effects on embryonic development. Conversely, EVs derived from cells under pathological conditions have shown a negative impact. This finding underscores the importance of the source and condition of EVs used in culture media. Further, the addition of EVs as a culture medium supplement holds significant therapeutic potential for optimizing in vitro embryo culture systems. In conclusion, this evaluation offers a thorough assessment of the available data on the role of EVs in embryo culture media and highlights the potential and challenges of using EVs in vitro embryo production.

Unveiling Invisible Extracellular Vesicles: Cutting-Edge Technologies for Their in Vivo Visualization.

Extracellular vesicles (EVs), nanosized lipid bilayer vesicles released by nearly all types of cells, play pivotal roles as intercellular signaling mediators with diverse biological activities. Their adaptability has attracted interest in exploring their role as disease biomarker theranostics. However, the invivo biodistribution and pharmacokinetic profiles of EVs, particularly following administration into living subjects, remain unclear. Thus, invivo imaging is vital to enhance our understanding of the homing and retention patterns, blood and tissue half-life, and excretion pathways of exogenous EVs, thereby advancing real-time monitoring within biological systems and their therapeutic applications. This review examines state-of-the-art methods including EV labeling with various agents, including optical imaging, magnetic resonance imaging, and nuclear imaging. The strengths and weaknesses of each technique are comprehensively explored, emphasizing their clinical translation. Despite the potential of EVs as cancer theranostics, achieving a thorough understanding of their invivo behavior is challenging. This review highlights the urgency of addressing current questions in the biology and therapeutic applications of EVs. It underscores the need for continued research to unravel the complexities surrounding EVs and their potential clinical implications. By identifying these challenges, this review contributes to ongoing efforts to optimize EV imaging techniques for clinical use. Ultimately, bridging the gap between research advancements and clinical applications will facilitate the integration of EV-based theranostics, marking a crucial step toward harnessing the full potential of EVs in medical practice.

Unraveling the Connection: Extracellular Vesicles and Non-Small Cell Lung Cancer.

Extracellular vesicles (EVs) are nanoscale lipid bilayer vesicles released during cell activation, cellular damage, or apoptosis. They carry nucleic acids, proteins, and lipids facilitating intercellular communication and activate signaling pathways in target cells. In non-small cell lung cancer (NSCLC), EVs may contribute to tumor growth and metastasis by modulating immune responses, facilitating epithelial-mesenchymal transition, and promoting angiogenesis, while potentially contributing to resistance to chemotherapy drugs. EVs in liquid biopsies serve as non-invasive biomarkers for early cancer detection and diagnosis. Due to their small size, inherent molecular transport properties, and excellent biocompatibility, EVs also act as natural drug delivery vehicles in NSCLC therapy.

Engineering strategies for apoptotic bodies.

Extracellular vesicles (EVs) are lipid bilayer vesicles containing proteins, lipids, nucleic acids, and metabolites secreted by cells under various physiological and pathological conditions that mediate intercellular communication. The main types of EVs include exosomes, microvesicles, and apoptotic bodies (ABs). ABs are vesicles released during the terminal stages of cellular apoptosis, enriched with diverse biological entities and characterized by distinct morphological features. As a result, ABs possess great potential in fields like disease diagnosis, immunotherapy, regenerative therapy, and drug delivery due to their specificity, targeting capacity, and biocompatibility. However, their therapeutic efficacy is notably heterogeneous, and an overdose can lead to side effects such as accumulation in the liver, spleen, lungs, and gastrointestinal system. Through bioengineering, the properties of ABs can be optimized to enhance drug-loading efficiency, targeting precision, and multifunctionality for clinical implementations. This review focuses on strategies such as transfection, sonication, electroporation, surface engineering, and integration with biomaterials to enable ABs to load cargoes and enhance targeting, providing insights into the engineering of ABs.

Exosome theranostics: Comparative analysis of P body and exosome proteins and their mutations for clinical applications.

Exosomes are lipid-bilayered vesicles, originating from early endosomes that capture cellular proteins and genetic materials to form multi-vesicular bodies. These exosomes are secreted into extracellular fluids such as cerebrospinal fluid, blood, urine, and cell culture supernatants. They play a key role in intercellular communication by carrying active molecules like lipids, cytokines, growth factors, metabolites, proteins, and RNAs. Recently, the potential of exosomal delivery for therapeutic purposes has been explored due to their low immunogenicity, nano-scale size, and ability to cross cellular barriers. This review comprehensively examines the biogenesis of exosomes, their isolation techniques, and their diverse applications in theranostics. We delve into the mechanisms and methods for loading exosomes with mRNA, miRNA, proteins, and drugs, highlighting their transformative role in delivering therapeutic payloads. Additionally, the utility of exosomes in stem cell therapy is discussed, showcasing their potential in regenerative medicine. Insights into exosome cargo using pre- or post-loading techniques are critical for exosome theranostics. We review exosome databases such as ExoCarta, Expedia, and ExoBCD, which document exosome cargo. From these databases, we identified 25 proteins common to both exosomes and P-bodies, known for mutations in the COSMIC database. Exosome databases do not integrate with mutation analysis programs; hence, we performed mutation analysis using additional databases. Accounting for the mutation status of parental cells and exosomal cargo is crucial in exosome theranostics. This review provides a comprehensive report on exosome databases, proteins common to exosomes and P-bodies, and their mutation analysis, along with the latest studies on exosome-engineered theranostics.

Calcium ions do not influence the Aβ(25–35) triggered morphological changes of lipid membranes

We have studied the effect of calcium ions (Ca2+) at various concentrations on the structure of lipid vesicles in the presence of amyloid-beta peptide Aβ(25–35). In particular, we have investigated the influence of calcium ions on the formation of recently documented bicelle-like structures (BLSs) emerged as a result of Aβ(25–35) triggered membrane disintegration. First, we have shown by using small-angle X-ray and neutron scattering that peptide molecules rigidify the lipid bilayer of gel phase DPPC unilamellar vesicles (ULVs), while addition of the calcium ions to the system hinders this effect of Aβ(25–35). Secondly, the Aβ(25–35) demonstrates a critical peptide concentration at which the BLSs reorganize from ULVs due to heating and cooling the samples through the lipid main phase transition temperature (Tm). However, addition of calcium ions does not affect noticeably the Aβ-induced formation of BLSs and their structural parameters, though the changes in peptide's secondary structure, e.g. the increased α-helix fraction, has been registered by circular dichroism spectroscopy. Finally, according to 31P nuclear magnetic resonance (NMR) measurements, calcium ions do not affect the lipid-peptide arrangement in BLSs and their ability to align in the magnetic field of NMR spectrometer. The influences of various concentrations of calcium ions on the lipid-peptide interactions may prove biologically important because their local concentrations vary widely in in-vivo conditions. In the present work, calcium ions were investigated as a possible tool aimed at regulating the lipid-peptide interactions that demonstrated the disruptive effect of Aβ(25–35) on lipid membranes.

Shedding Light on the Role of Exosomal PD-L1 (ExoPD-L1) in Cancer Progression: an Update.

Exosomes are the primary category of extracellular vesicles (EVs), which are lipid-bilayer vesicles with biological activity spontaneously secreted from either normal or tansformed cells. They serve a crucial role for intercellular communication and affect extracellular environment and the immune system. Tumor-derived exosomes (TEXs) enclose high levels of immunosuppressive proteins, including programmed death-ligand 1 (PD-L1). PD-L1 and its receptor PD-1 act as crucial immune checkpoint molecules, thus facilitating tumor advancement by inhibiting immune responses. PDL-1 is abundantly present on tumor cells and interacts with PD-1 on activated T cells, resulting in T cell suppression and allowing immune evasion of cancer cells. Various FDA-approved monoclonal antibodies inhibiting the PD-1/PD-L1 interaction are commonly used to treat a diverse range of tumors. Although the achieved results are significant, some individuals have a poor reaction to PD-1/PD-L1 blocking. PD-L1-enriched TEXs may mimic the impact of cell-surface PD-L1, consequently potentiating tumor resistance to PD1/PD-L1 based therapy. In light of this, a strong correlation between circulating exosomal PD-L1 levels and response rate to anti-PD-1/PD-L1 antibody treatment has been evinced. This article inspects the function of exosomal PDL-1 in developing resistance to anti-PD-1/PD-L1 therapy for opening new avenues for overcoming tumor resistance to such modalities and development of more favored combination therapy.

Effects of inserting ultrashort carbon nanotubes into lipid bilayers on membrane morphology

AbstractSingle‐walled carbon nanotubes (CNTs) are carbon materials with unique thermal, optical, mechanical, and electrical properties, with hollow cylindrical structures of a few nanometers in diameter. CNTs cut to about 10 nm (Ultrashort CNTs, US‐CNTs) can spontaneously insert into lipid bilayers. Therefore, applications have been proposed to combine CNTs with lipid bilayers to give the membranes the properties of CNTs. However, CNTs interact with membranes to induce morphological changes in the membranes, which may hinder these applications. In this study, to investigate the effects, US‐CNTs are exposed to lipid bilayer vesicles (giant unilamellar vesicles, GUVs), which are used as a model for cell membranes, and the changes in membrane morphology with each US‐CNT concentration were evaluated by fluorescence microscopy. As a result, GUVs show morphological changes upon exposure to US‐CNTs, eventually transforming into a multiple vesicle‐linked shape. This result suggests an increase in the area and asymmetry of the GUV membrane. Based on these results, we have proposed a hypothesis regarding the mechanism of morphological changes induced in the GUV membranes by US‐CNTs exposure.

A randomised phase 2 study of liposomal irinotecan in combination with 5-fluorouracil/leucovorin and oxalipalatin versus nab-paclitaxel plus gemcitabine in unresectable locally advanced or metastatic pancreatic cancer.

4141 Background: FOLFIRINOX remained as first-line standard of care. However, FOLFIRINOX often requires dose modifications, delays and growth factor support due to excessive toxicity which can complicate care delivery. Liposomal irinotecan (HE072) is a liposomal formulation that encapsulates irinotecan in a lipid bilayer vesicle, as a generic drug, had been approved for marketing in China on September 15, 2022, and was used in combination with 5-fluorouracil (5-FU) and leucovorin for patients with metastatic pancreatic cancer who progressed after receiving gemcitabine treatment. This study aims to compare with nab-paclitaxel+gemcitabine (AG), which is another first-line stand of care, through substitute HE072 for traditional irinotecan in the standard FOLFIRINOX regimen (NALIRIFOX) and to demonstrate safe and effective delivery. Methods: HE072-CSP-004 was a randomised, open-label, multi-center, phase 2 study. Patients with unresectable locally advanced or metastatic pancreatic cancer were randomly assigned (2:1) to receive NALIRIFOX (HE072 50 mg/m², oxaliplatin 60 mg/m², leucovorin 400 mg/m², and fluorouracil 2400 mg/m², administered sequentially as a continuous intravenous infusion over 46 h) on days 1 and 15 of a 28-day cycle or AG (nab-paclitaxel 125 mg/m² and gemcitabine 1000 mg/m²), administered intravenously, on days 1, 8, and 15 of a 28-day cycle. Other key eligibility criteria include ECOG performance status of 0 to 1, untreated with systematic anti-tumor regimens; Primary endpoint was progression-free survival (PFS). Secondary endpoints included objective response rate (ORR), overall survival (OS), disease control rate (DCR), and duration of response (DOR). Results: As of Dec 12, 2023, 117 patients were randomly assigned (NALIRIFOX, 78; AG, 39). The two groups were comparable on baseline characteristics. The median PFS differences was statistically significant as 7.6 months (95%CI 5.49-9.17) with NALIRIFOX versus 3.7 months (95%CI 3.15-5.06) with AG (hazard ratio 0.55; 95% CI 0.34-0.87; p=0.0104). Median OS was 13.4 months (95%CI 9.89-NE) with NALIRIFOX versus 8.8 months (95%CI 6.87-12.16) with AG (hazard ratio 0.66; 95% CI 0.39-1.11; p=0.1125). Grade 3 or higher treatment-emergent adverse events (TRAE) occurred in 52 (66.7%) of 78 patients receiving NALIRIFOX and 30 (76.9%) of 39 patients receiving AG. No new safety signal was observed. Conclusions: The study met the primary endpoint of PFS demonstrating statistically significant and clinically meaningful improvements in PFS and with a trend of OS benefit for NALIRIFOX over AG. The safety profile was consistent with the known risks of the individual toxicity. This study is consistent with the existing NAPOLI 3 study. Clinical trial information: NCT05047991 .

A phase II study of liposomal irinotecan-based chemotherapy with or without PD-1 inhibitor in patients with unresectable locally advanced or metastatic biliary tract cancer.

e15077 Background: Clinical outcomes for advanced biliary tract cancer (BTC) patients (pt) progressed on first-line therapy remain dismal. Liposomal irinotecan (LI) (HE072) is a formulation encapsulating I in a lipid bilayer vesicle and was approved in China in September 2022. It was used with 5-fluorouracil (5-FU) and leucovorin (LV) for patients with metastatic pancreatic cancer progressing on gemcitabine treatment. We conducted an phase II study to investigate HE072 in combination with 5-FU and LV with or without a novel PD-1 inhibitor SG001 in patients with advanced BTC progressed on prior gemcitabine-based chemotherapy. Methods: This is a multi-center, non-randomized, open label phase II study in pts with unresectable locally advanced or metastatic BTC. Key inclusion factors were ECOG PS 0-1, prior gemcitabine-based chemotherapy, evidence of disease progression with at least one measurable lesion and adequate haematological/organ function. Key exclusion factor was brain metastases. Pts were treated with liposomal irinotecan (70 mg/m2) plus LV (400 mg/m2f) and 5-FU (2400 mg/m2) with or without SG001 (240mg) IV every 2 weeks for up to 2 years in absence of disease progression or unacceptable toxicity. Tumor assessments based on RECIST 1.1 were performed every 6 weeks by investigators. Primary endpoint was objective response rate (ORR). Secondary endpoints include progression free survival (PFS), overall survival (OS), disease control rate (DCR) and safety. Results: As of April 25, 2023, 17 BTC pts were enrolled into liposomal irinotecan-based chemotherapy arm (n = 7) and liposomal irinotecan-based chemotherapy plus SG001 arm (n = 10). ORR and DCR were 14.3% and 71.4% for chemotherapy arm, 20% and 40% for chemotherapy+ SG001 arm. Median OS and PFS for chemotherapy arm was 11.5(95% CI, 3.9-NE) and 4.2(95% CI, 1.4-NE) months, and for chemotherapy+PD-1 arm was 15.3 (95% CI, 3.6-17.0) and 3.8(95% CI, 1.4-6.9) months. All pts experienced treatment-related adverse events (TRAEs). The incidence of grade≥3 TRAEs was 58.8%(10/17), which occurred in 57% (4/7) of pts treated in chemotherapy arm vs 60% (6/10) in chemotherapy+SG001 arm. Among all patients, the most frequent grade ≥3 TRAEs were fatigue (29.4%), neutropenia (23.5%) and leukopenia (23.5%). One grade 4 TRAE leading to dose reduction in liposomal irinotecan was febrile neutropenia in chemotherapy arm. There were no treatment-related deaths. Conclusions: These preliminary results suggested that liposomal irinotecan plus 5-FU and LV was well-tolerated and showed promising and durable clinical activity in advanced BTC pts progressed on first-line treatment. Combined use of SG001 further improved clinical outcome in these pts without increased toxicity. Combination of liposomal irinotecan, 5-FU, LV and PD-1 inhibitor is a treatment strategy which is worthy of further exploration.

A phase 1 study of liposomal irinotecan in patients with advanced breast cancer.

1080 Background: Liposomal irinotecan (HE072) is a liposomal formulation that encapsulates irinotecan in a lipid bilayer vesicle, and as a generic drug, had been approved in China, recently, in patients with pancreatic cancer after gemcitabine treatment. Advanced triple negative breast cancer (TNBC) has very poor prognosis and limited treatment choices. Here we present results of breast cancer treated with HE072 in patients with highly pre-treated metastatic TNBC and HER2 negative breast cancer brain metastasis (BCBM). Methods: HE072-CSP-002 was a phase 1 study, consisting of two parts, dose escalation and expansion part (part 1) and expansion cohort part (part 2). In part 1, standard 3+3 design was used to investigate up to three dose levels of HE072 (50 mg/m2, 70 mg/m2 and 90 mg/m2), up to 6-9 additional subjects may be enrolled for dose expansion. In part 2, patients were enrolled in two cohorts (TNBC cohort and BCBM cohort), and received HE072 70 mg/m2 every two weeks (Q2W). The primary endpoints were the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D), and the incidence and severity of treatment emergent adverse events (TEAEs). Secondary endpoints included progression free survival (PFS), objective response rate (ORR), overall survival (OS). Results: As of June 5th, 2023, 119 patients were enrolled, including 101 patients with TNBC and 18 patients with HER2 negative BCBM (part 1: n=27; part 2: n=92). In the part 1, one dose-limiting toxicity (grade 3 nausea and grade 3 vomiting) was observed at 70 mg/m2 dose level, and MTD was not reached. A total of 115 patients (96.6%) had at least one TEAEs of any grade, and 55 patients (46.2%) had ≥grade 3 TEAEs. The most common ≥grade 3 TEAEs related to HE072 included neutropenia (21.0%), leukopenia (18.5%), diarrhea (10.1%), anemia (9.2%) and hypokalemia (8.4%). Eighty-three (82.2%) of the 101 patients with TNBC were evaluable for response. After a median follow-up of 10.1 months (range 8.8-10.8), 22 patients (26.5%, 95%CI 17.4-37.3) achieved overall response, which were all partial response and 58 patients (69.9%, 95%CI 58.8-79.5) achieved disease control. The median PFS and OS were 4.8 months (95%CI 3.9-5.8) and 14.1 months (95%CI 11.2-not reached), respectively. 12(66.7%) of the 18 patients with HER2 negative BCBM were evaluable for response. 1 patient (8.3%, 95%CI 0.2, 38.5) achieved overall response, which is partial response and 8 patients (66.7%, 95%CI 34.9, 90.1) achieved disease control. The median PFS was 5.6 months (95%CI 1.4~ not reached), 12-month OS rate was 55.5%. Conclusions: HE072 exhibited excellent antitumor activity in heavily pre-treated patients with TNBC and HER2 negative BCBM with acceptable safety profiles. 70 mg/m2 Q2W was determined as the RP2D. Further clinical trials are under plan. Clinical trial information: NCT04728035 .

Cryo-EM images of phase-separated lipid bilayer vesicles analyzed with a machine-learning approach

Lateral lipid heterogeneity (i.e., raft formation) in biomembranes plays a functional role in living cells. Three-component mixtures of low- and high-melting lipids plus cholesterol offer a simplified experimental model for raft domains in which a liquid-disordered (Ld) phase coexists with a liquid-ordered (Lo) phase. Using such models, we recently showed that cryogenic electron microscopy (cryo-EM) can detect phase separation in lipid vesicles based on differences in bilayer thickness. However, the considerable noise within cryo-EM data poses a significant challenge for accurately determining the membrane phase state at high spatial resolution. To this end, we have developed an image-processing pipeline that utilizes machine learning (ML) to predict the bilayer phase in projection images of lipid vesicles. Importantly, the ML method exploits differences in both the thickness and molecular density of Lo compared to Ld, which leads to improved phase identification. To assess accuracy, we used artificial images of phase-separated lipid vesicles generated from all-atom molecular dynamics simulations of Lo and Ld phases. Synthetic ground-truth data sets mimicking a series of compositions along a tieline of Ld + Lo coexistence were created and then analyzed with various ML models. For all tieline compositions, we find that the ML approach can correctly identify the bilayer phase with >90% accuracy, thus providing a means to isolate the intensity profiles of coexisting Ld and Lo phases, as well as accurately determine domain-size distributions, number of domains, and phase-area fractions. The method described here provides a framework for characterizing nanoscopic lateral heterogeneities in membranes and paves the way for a more detailed understanding of raft properties in biological contexts.

The potential roles of exosomes in pathological cardiomyocyte hypertrophy mechanisms and therapy: A review.

Pathological cardiac hypertrophy, characterized by the enlargement of cardiac muscle cells, leads to serious cardiac conditions and stands as a major global health issue. Exosomes, comprising small lipid bilayer vesicles, are produced by various cell types and found in numerous bodily fluids. They play a pivotal role in intercellular communication by transferring bioactive cargos to recipient cells or activating signaling pathways in target cells. Exosomes from cardiomyocytes, endothelial cells, fibroblasts, and stem cells are key in regulating processes like cardiac hypertrophy, cardiomyocyte survival, apoptosis, fibrosis, and angiogenesis within the context of cardiovascular diseases. This review delves into exosomes' roles in pathological cardiac hypertrophy, first elucidating their impact on cell communication and signaling pathways. It then advances to discuss how exosomes affect key hypertrophic processes, including metabolism, fibrosis, oxidative stress, and angiogenesis. The review culminates by evaluating the potential of exosomes as biomarkers and their significance in targeted therapeutic strategies, thus emphasizing their critical role in the pathophysiology and management of cardiac hypertrophy.

Advancements and Clinical Significance of Breast Cancer Exosome Detection

Exosomes, which are lipid bilayer vesicles actively secreted by cells with a diameter of 30-100 nm, play a crucial role in the occurrence, development, and formation of the tumor microenvironment in breast cancer. They have become an important component of liquid biopsies for breast cancer and ideal targets for early diagnosis, treatment assessment, and clinical therapy. Breast cancer is the most common malignancy among women. However, traditional exosome detection methods have several limitations, and there are still many difficulties and challenges in achieving widespread clinical application of exosomes. Nowadays, significant progress has been made in exosome detection and analysis techniques, including optical methods such as colorimetry, fluorescence, surface-enhanced Raman scattering, as well as various electrochemical and thermal signal methods. This review summarizes the current biomarkers and novel developments in detection techniques applied to liquid biopsy of exosomes in breast cancer.

Revolutionizing Ischemic Stroke Diagnosis and Treatment: The Promising Role of Neurovascular Unit-Derived Extracellular Vesicles.

Ischemic stroke is a fatal and disabling disease worldwide and imposes a significant burden on society. At present, biological markers that can be conveniently measured in body fluids are lacking for the diagnosis of ischemic stroke, and there are no effective treatment methods to improve neurological function after ischemic stroke. Therefore, new ways of diagnosing and treating ischemic stroke are urgently needed. The neurovascular unit, composed of neurons, astrocytes, microglia, and other components, plays a crucial role in the onset and progression of ischemic stroke. Extracellular vesicles are nanoscale lipid bilayer vesicles secreted by various cells. The key role of extracellular vesicles, which can be released by cells in the neurovascular unit and serve as significant facilitators of cellular communication, in ischemic stroke has been extensively documented in recent literature. Here, we highlight the role of neurovascular unit-derived extracellular vesicles in the diagnosis and treatment of ischemic stroke, the current status of extracellular vesicle engineering for ischemic stroke treatment, and the problems encountered in the clinical translation of extracellular vesicle therapies. Extracellular vesicles derived from the neurovascular unit could provide an important contribution to diagnostic and therapeutic tools in the future, and more studies in this area should be carried out.

Formulation optimization and PK/PD evaluation of novel valsartan bilosomes enhancing transdermal drug delivery

RationaleThe skins capillary network makes it the bodys most accessible organ. However, the topmost layer of skin, known as stratum corneum (SC), is a substantial diffusional barrier for most drugs. It is suggested that edge activators (EAs) may provide the lipid bilayer of innovative elastic vesicles with ultra-flexibility that can penetrate SC employing high self-optimising deformability. It is fact that the therapeutic activity of lipophillic drugs can be improvized by incorporating novel formulations into the colloidal system. Aim and objectThe primary objective of this research work focused to formulation and optimization of novel bilosomes containing valsartan (VLT). MethodsThin film hydration (TFH) technique developed bilosomes in a 33-factorial design. Valsartan bilosomes (VLT-B) and valsartan bilosomal gels (VLT-BG) efficacy was assessed using ex vivo, in vitro and in vivo investigations. ResultsVLTBG had a higher area under the curve (AUC) and plasma concentration (Cmax) in the tested animals than the VLT oral solution. The optimised VLTB had 136.48 ± 7.82 nm diameter, −48.37 ± 0.49 mV of surface charge, and 88.56 ± 1.73 % of drug encapsulation. Oral VLT solution and VLT bilosomal gel Cmax were 52.37 and 215.39 μg/mL at 2 and 16 h, respectively. The AUC(0–∞) with the oral and transdermal application of the VLTBG was found to be 0.430 μg h/mL and 67.21 μg h/mL, respectively. ConclusionThe outcomes supported the hypothesis that bilosomes enhance VLT flow and concluded that the skin is better than the drug solution.