Phospholipid Bilayer Vesicles Research Articles

Emerging Microfluidic Tools for Simultaneous Exosomes and Cargo Biosensing in Liquid Biopsy: New Integrated Miniaturized FFF-Assisted Approach for Colon Cancer Diagnosis

The early-stage diagnosis of cancer is a crucial clinical need. The inadequacies of surgery tissue biopsy have prompted a transition to a less invasive profiling of molecular biomarkers from biofluids, known as liquid biopsy. Exosomes are phospholipid bilayer vesicles present in many biofluids with a biologically active cargo, being responsible for cell-to-cell communication in biological systems. An increase in their excretion and changes in their cargo are potential diagnostic biomarkers for an array of diseases, including cancer, and they constitute a promising analyte for liquid biopsy. The number of exosomes released, the morphological properties, the membrane composition, and their content are highly related to the physiological and pathological states. The main analytical challenge to establishing liquid biopsy in clinical practice is the development of biosensors able to detect intact exosomes concentration and simultaneously analyze specific membrane biomarkers and those contained in their cargo. Before analysis, exosomes also need to be isolated from biological fluids. Microfluidic systems can address several issues present in conventional methods (i.e., ultracentrifugation, size-exclusion chromatography, ultrafiltration, and immunoaffinity capture), which are time-consuming and require a relatively high amount of sample; in addition, they can be easily integrated with biosensing systems. A critical review of emerging microfluidic-based devices for integrated biosensing approaches and following the major analytical need for accurate diagnostics is presented here. The design of a new miniaturized biosensing system is also reported. A device based on hollow-fiber flow field-flow fractionation followed by luminescence-based immunoassay is applied to isolate intact exosomes and characterize their cargo as a proof of concept for colon cancer diagnosis.

Plant-derived nanovesicles: Further exploration of biomedical function and application potential.

Extracellular vesicles (EVs) are phospholipid bilayer vesicles actively secreted by cells, that contain a variety of functional nucleic acids, proteins, and lipids, and are important mediums of intercellular communication. Based on their natural properties, EVs can not only retain the pharmacological effects of their source cells but also serve as natural delivery carriers. Among them, plant-derived nanovesicles (PNVs) are characterized as natural disease therapeutics with many advantages such as simplicity, safety, eco-friendliness, low cost, and low toxicity due to their abundant resources, large yield, and low risk of immunogenicity invivo. This review systematically introduces the biogenesis, isolation methods, physical characterization, and components of PNVs, and describes their administration and cellular uptake as therapeutic agents. We highlight the therapeutic potential of PNVs as therapeutic agents and drug delivery carriers, including anti-inflammatory, anticancer, wound healing, regeneration, and antiaging properties as well as their potential use in the treatment of liver disease and COVID-19. Finally, the toxicity and immunogenicity, the current clinical application, and the possible challenges in the future development of PNVs were analyzed. We expect the functions of PNVs to be further explored to promote clinical translation, thereby facilitating the development of a new framework for the treatment of human diseases.

No Life on this Planet Without PHB

AbstractThe history of discovery byRosetta Reuschof oligo‐ and poly‐β‐hydroxybutyrates (OHBs and PHBs) consisting of less thanca. 150 HB units is described. These ‘short‐chain’ biopolymers can be detected in all living organisms and have numerous physiological activities of fundamental importance for the chemistry of life. The largest are components of ion channels such as Ca2+‐polyphosphate‐PHB (Ca‐PPi‐PHB) in genetically competentE. coliand in mammalian mitochondria. Sequences with chain lengths <ca. 30 occur covalently attached to proteins (post‐translational PHBylation), and methyl esters of the dimer and trimer are used by certain bacteria as highly efficient antioxidants. With synthetic monodisperse OHBs (up to 128mer) our group has contributed structural investigations, and we have shown that OHBs≥16 alone make phospholipid bilayer vesicles permeable to Ca ions. An extensive biochemical analysis of the TRPM8 protein channel, responsible for the sense of heat in our skin, proved to be fully active only when PHBylated. Reasons for the difficulty of detecting OHBs and PHBs are discussed: the polyester chain is highly flexible, and there is ester cleavage by base, acid, nucleophiles,Lewisacids, and heat – in stark contrast to peptides. PHBs may be called a ubiquitous butfleetingspecies in the chemistry of life – worth being appreciated and studied much more intensively in the future! A speculation about PHB's possible role in prebiotic compartmentalization is presented, and recent uses of compartmentalization in organic synthesis are briefly mentioned.Portions of the figures used herein were presented in a lecture at the International Symposium on Biopolymers on September 13, 2022, in Sion (Switzerland).

Tumor-targeted exosomes for delivery of anticancer drugs

Exosomes are small phospholipid bilayer vesicles that are naturally produced by all living cells, both prokaryotes and eukaryotes. The exosomes due to their unique size, reduced immunogenicity, and their ability to mimic synthetic liposomes in carrying various anticancer drugs have been tested as drug delivery vehicles for cancer treatment. An added advantage of developing exosomes as a drug carrier is the ease of manipulating their intraluminal content and their surface modification to achieve tumor-targeted drug delivery. In the past ten-years, there has been an exponential increase in the number of exosome-related studies in cancer. Preclinical studies demonstrate exosomes-mediated delivery of chemotherapeutics, biologicals and natural products produce potent anticancer activity both, in vitro and in vivo. In contrast, the number of exosome-based clinical trials are few due to challenges in the manufacturing and scalability related to large-scale production of exosomes and their storage and stability. Herein, we discuss recent advances in exosome-based drug delivery for cancer treatment in preclinical and clinical studies and conclude with challenges to be overcome for translating a larger number of exosome-based therapies into the clinic.

The Role and Application of Exosomes and Their Cargos in Reproductive Diseases: A Systematic Review.

In recent years, the incidence of the reproductive diseases is increasing year-by-year, leading to abortion or fetal arrest, which seriously affects the reproductive health of human beings and the reproductive efficiency of animals. Exosomes are phospholipid bilayer vesicles that are widely distributed in living organisms and released by the cells of various organs and tissues. Exosomes contain proteins, RNA, lipids, and other components and are important carriers of information transfer between cells, which play a variety of physiological and pathological regulatory functions. More and more studies have found that exosomes and their connotations play an important role in the diagnosis, prognosis and treatment of diseases. A systematic review was conducted in this manuscript and then highlights our knowledge about the diagnostic and therapeutic applications of exosomes to reproductive diseases, such as polycystic ovary syndrome (PCOS), endometriosis, premature ovarian failure (POF), preeclampsia, polycystic, endometrial cancer, cervical cancer, ovarian cancer, and prostate gland cancer.

Extracellular vesicles derived from microgreens of Raphanus sativus L. var. caudatus Alef contain bioactive macromolecules and inhibit HCT116 cells proliferation

Extracellular vesicles (EVs) are phospholipid bilayer vesicles released from cells, containing natural cargos. Microgreens of Raphanus sativus L. var. caudatus Alef were used in this study as the source of EVs. EVs were isolated by differential centrifugation. The physical properties were determined by dynamic light scattering (DLS) and electron microscopy. The biological and chemical composition were studied by Fourier-transform infrared (FTIR) microspectroscopy and high-performance liquid chromatography analysis, respectively. EVs had a median size of 227.17 and 234.90 ± 23.30 nm determined by electron microscopy and DLS, respectively with a polydispersity index of 0.293 ± 0.019. Electron microscopy indicated the intact morphology and confirmed the size. The FTIR spectra revealed that EVs are composed of proteins as the most abundant macromolecules. Using a curve-fitting analysis, β-pleated sheets were the predominant secondary structure. Notably, the micromolecular biomarkers were not detected. EVs exerted anti-cancer activity on HCT116 colon cancer over Vero normal cells with an IC50 of 448.98 µg/ml and a selectivity index of > 2.23. To conclude, EVs could be successfully prepared with a simple and effective isolation method to contain nano-sized macromolecules possessing anti-cancer activity.

Prospect of exosomal circular RNAs in breast Cancer: presents and future.

Implementing precision oncology for breast cancer (BC) is a critical method for improving patient outcomes, which relies on the use of reliable biomarkers to be effective and safe. exosomes represent a potential alternative for the diagnosis and therapy of BC, As a "liquid biopsy" and a novel source for biomarkers. Exosomes are nanoscale phospholipid bilayer vesicles released by most cells that contain a large payload of various RNA species that can alter recipient cell activity. Circular RNAs (circRNAs) were recently revealed as a looping subclass of competing endogenous noncoding RNAs (ceRNAs) capable of microRNA sponging to regulate gene expression. They provide critical regulatory functions in carcinogenesis, proliferation, invasion, metastasis, and treatment resistance, as well as cancer prognostic. However, there is still a major gap in our understanding of the role of circRNA in the advancement of BC. CircRNAs are abundant in exosomes, according to various studies, and exosomal circRNAs (exo-circRNAs) play a significant role in cancer biology. Exo-circRNAs can be picked up by nearby or distant cells, affecting many features of the target cells' pathophysiological states, thus boosting cell communication and tumor spread. In this review, we have briefly summarized the major properties and functions of exosomes. Then, we have focused on exo-circRNAs, discussing their potential roles in both driving and inhibiting BC, as well as for cancer diagnosis, prognosis, and monitoring.

Liposomes as immunological adjuvants and delivery systems in the development of tuberculosis vaccine: A review

Liposomes are phospholipid bilayer vesicles, which are biocompatible, biodegradable and nontoxic vehicles suitable for numerous drug and gene delivery applications. In this review, we discuss the prospect of using liposome technology in the development of a vaccine for tuberculosis. Tuberculosis remains an important health problem that requires the development of an effective vaccine, especially since the only approved vaccine for it continues to be the Bacille Calmette-Geurin (BCG) one developed 100 years ago. This review focuses on the different applications of liposomes toward achieving this goal. Numerous liposomal formulations showing prospect in the research stage and in clinical trials are discussed.

Latest Trend of Milk Derived Exosomes: Cargos, Functions, and Applications.

Exosomes are nanosized phospholipid bilayer vesicles released to the extracellular environment. Exosomes from various tissues or cells are being studied and there has been a growing interest in milk exosomes research due to their emerging role as messengers between cells and the fact that it can be produced in large quantities with rich source of milk. Milk derived exosomes (MDEs) contain lipids, microRNAs, proteins, mRNAs as well as DNA. Studies of exosome cargo have been conducted widely in many research areas, especially exosomal miRNAs. In this paper, we reviewed the current knowledge in isolation and identification, cargos, functions mainly in intestinal tract and immunity system of MDEs. Its application as drug carriers and diseases biomarker are also discussed. Furthermore, we also consider critical challenges of MDEs application and provide possible directions for future research.

Metal Substrate Selectivity and Mechanism of Transport in a Transmembrane Zn‐pump Revealed by in‐vitro Real‐time Transport

P1B-type ATPases are primary active transmembrane metal pumps conserved in all kingdoms of life that play a pivotal role in controlling cellular metal ion levels and homeostasis. In bacteria, they are responsible for selectively exporting essential and toxic metal ions across the cell membrane to maintain concentrations below toxic levels. They are critical virulence factors in pathogenic bacteria and allow selected microorganisms to survive in extreme metal-rich environments. The P1B-2-type Zn(II) ATPase pump subfamily possesses a wide promiscuity towards metal substrate translocation by plastic selection of Zn(II)/Cd(II)/Hg(II)/Pb(II) at their high-affinity transmembrane metal binding site. Despite these substrates stimulate ATP-hydrolysis, direct translocation of all these metals and their mechanism of transport remain to be demonstrated. In this work, we established a platform for purification and in-vitro functional reconstitution in artificial phospholipid bilayer vesicles (proteoliposomes) of ZntA from Cupriavidus metallidurans to dissect the molecular mechanism of divalent metal ion translocation and substrate promiscuity towards first-, second- and the third-row transition metals. Metal-dependent ATPase activity assays of CmΔZntA166–794 in detergent micelles and proteoliposomes revealed stimulation of the ATPase activity by Pb(II), Zn(II), Cd(II) and Hg(II) substrates with the maximal velocities (Vmax) following the order Pb(II) > Zn(II) > Cd(II) > Hg(II), confirming the successful functional reconstitution in lipid vesicles. By selecting and encapsulating divalent metal sensitive fluorescent probes in the proteoliposome lumen, we performed real-time metal transport assays to reveal the ATP-dependent translocation of Pb(II), Zn(II), Cd(II) and Hg(II) across the lipid bilayer, establishing that the translocation rates correlate to the order observed following ATP hydrolysis. Furthermore, to dissect the substrate transport mechanism, we encapsulated the pH sensitive fluorescent probe pyranine to demonstrated that, differently than other P-type ATPases, translocation is not coupled to H+ counter-flux for all the M(II) substrates. By encapsulating the membrane potential sensitive fluorescent probe Oxonol-VI we also revealed that, with all substrates, Zn-pumps act as primary active electrogenic uniporters capable of generating a transmembrane potential. This work establishes a platform to dissect the mechanisms of translocation of various metal substrates in P-type ATPases which is applicable to study other uncharacterized transporter families and to reveal the bioinorganic chemistry of metal ion transport at molecular level.

Insights Into Exosomal Non-Coding RNAs Sorting Mechanism and Clinical Application.

Exosomes are natural nanoscale bilayer phospholipid vesicles that can be secreted by almost all types of cells and are detected in almost all types of body fluids. Exosomes are effective mediators of cell–cell signaling communication because of their ability to carry and transfer a variety of bioactive molecules, including non-coding RNAs. Non-coding RNAs have also been found to exert strong effects on a variety of biological processes, including tumorigenesis. Many researchers have established that exosomes encapsulate bioactive non-coding RNAs that alter the biological phenotype of specific target cells in an autocrine or a paracrine manner. However, the mechanism by which the producer cells package non-coding RNAs into exosomes is not well understood. This review focuses on the current research on exosomal non-coding RNAs, including the biogenesis of exosomes, the possible mechanism of sorting non-coding RNAs, their biological functions, and their potential for clinical application in the future.

Exosomal circular RNA sorting mechanisms and their function in promoting or inhibiting cancer.

Exosomes are nanoscale phospholipid bilayer vesicles that can be artificially engineered into vectors for the treatment of cancer. Circular RNA (circRNA), a type of non-coding RNA, has crucial regulatory functions in various aspects of cancer, such as tumorigenesis, apoptosis, proliferation, invasion, metastasis and chemo- and radiotherapeutic resistance, as well as in cancer prognosis. Notably, the exosomal transfer of circRNAs may function to both promote and inhibit cancer. Numerous studies have addressed the importance of circRNAs in cancer and non-coding RNAs (such as microRNAs and long non-coding RNAs) in exosomes. However, little research has focussed on a class of RNAs called exosomal circRNAs. The present review discusses current studies regarding exosomal circRNAs, including their biogenesis and biological functions, their abundance in exosomes and possible sorting mechanisms and their potential roles in both promoting and inhibiting cancer. It is predicted that in the next five years there will be increasing research exploring the functional mechanisms of exosomal circRNA in various diseases, in particular their roles in cancer genesis and progression.

Cationic liposome-triggered luminol chemiluminescence reaction and its applications.

Liposomes are spherical phospholipid bilayer vesicles. In the present study, we found that cationic liposomes made by (2,3-dioleoyloxy-propyl)-trimethylammonium (DOTAP) could enhance the luminol-H2O2 chemiluminescence (CL) reaction. Mechanism studies showed that the positive charge on the surface of liposomes plays an important role in the CL process. We speculated that the cationic liposomes with quaternary ammonium groups on the surface may be capable of catalyzing the decomposition of H2O2 leading to the formation of oxygen-related free radicals including ˙OH, 1O2, and O2˙-. The luminol anions tend to move close to the surface of the cationic liposomes and then to be oxidized by the oxidizing radical species which may be around the surface of cationic liposomes forming excited-state 3-aminophthalate* (3-APA*). When the 3-APA* returns to the ground state, an enhanced CL is observed. In addition, the single-strand DNA (ssDNA) showed a significant inhibition effect on the proposed CL reaction. The CL intensity decreased linearly with an increasing amount of DNA from 0.05 to 2 pmol. We assumed that the binding of ssDNA with cationic liposomes would neutralize the positive charge on the surface of liposomes and inhibit the catalytic activity of DOTAP cationic liposomes. Based on the ssDNA-inhibited luminol-H2O2-cationic liposome CL reaction, simple label-free CL sensing platforms were developed for the detection of sequence-specific DNA related to the hepatitis B virus (HBV) gene and for the detection of ATP (as a model analyte) using an anti-ATP aptamer as the recognition element.

Chiral Recognition of Lipid Bilayer Membranes by Supramolecular Assemblies of Peptide Amphiphiles.

On the basis of the exclusive existence of homochirality in biomolecules and the well-known phenomenon of chiral recognition, it is obvious that chirality is a crucial factor in biological events. We report here that supramolecular assemblies of peptide amphiphiles interact with lipid bilayer membranes in a stereospecific manner. When negatively charged chiral phospholipid bilayer vesicles were subjected to the assemblies, we found that peptide amphiphiles with l-amino acids show stronger affinity for the liposomes compared to the ones with d-amino acids. To examine their biological functions, we tested the cytotoxicity of nanofibers against mammalian primary cells using human bone marrow mesenchymal stem cells and murine astroglial cells. We demonstrated that cell viability increased when d-amino acids were incorporated in the structure of peptide amphiphiles, which is consistent with our finding of their weaker interactions with lipid bilayer membranes.

Liposomal Formulations In Cancer Therapy: Passive Versus Active Targeting

In Cancer therapy, Nano drug delivery system comprising of Liposomes, are the most successful mode of treatment in present scenario which also has real time clinical application. Recently it is found that the closed bilayer phospholipid vesicles have many technical advantages over the initially used liposomal formulations. The delivery of therapeutics encapsulated in liposomes changes the biological distribution profile and improves the drug therapeutic indices of various drugs. This review article throws light onto many clinical liposomal drug delivery products. The liposome Nano drug delivery by the active and passive targeting is a boon as it can reduce the off-targeting effects. The current development is more focused on the diagnostic and clinical applications. Receptor targeted delivery systems are extensively explored for active targeting. However, these delivery systems are rarely seen in the clinical application because of conjugation chemistry and other implicit hurdles to develop this system.The development of nanocarriers in the cancer treatment have enormous potential in the medical field. Moreover, Immuno liposomes have been used in cancer treatment as attractive drug targeting vehicles. On the other hand, there are many other liposomal drug delivery systems having passive targeting mechanism for cancer treatment which are widely used due to enhanced retention and permeability of formulation. This review majorly focuses on the current challenges encountered in development of liposomal Nano drug delivery systems and its effective development for cancer treatment.

Applications liposome in cancer drug delivery and treatment: A review

In the world the biggest challenges to cure the cancer because of the abnormal cancer cells growth in the human body which is near to uncontrollable. These cells known as the malignant cell because it produced the cancer. There are several treatments for cancer such as surgery, chemotherapy, radiation treatment etc. however such treatments have major side effects like normal cell got killed, loss of hair, the surgery person skill also in consideration and high chances of reoccurrences. Due to such side effects these treatment drugs are less popular. To reduces such side effects the liposomal based treatments are the most preferable solution. The liposomes are the phospholipid bilayer vesicles and it has high encapsulation capacity. Therefore, liposomal based treatment plays significant role in the cancer treatment with less toxicity and other many advantages. The liposomal based drug pegylated liposomal doxorubicin and daunorubicin have advanced effect in the body. Furthermore, the development of the liposomes as immunoliposomes, ligand targeted and molecular targeting. This review explores the liposomal based drug delivery system, its advance effect on the cancer cells and clinically approve liposomes formulations.

Exosome-mediated peritoneal dissemination in gastric cancer and its clinical applications.

The prognosis of patients with peritoneal dissemination from gastric cancer is poor, and the underlying molecular mechanism remains unclear. Exosomes, as macromolecular phospholipid bilayer vesicles comprising of proteins, nucleic acids and lipids, serve as mediators of cell-cell communication. Gastric cancer tumor-derived exosomes may be involved in the pathological process of peritoneal dissemination by mediating crosstalk between cancer cells and mesothelial cells, to result in the induction of enhanced tumor growth, migratory, adhesive and invasive abilities, peritoneal fibrosis and apoptosis, mesothelial-to-mesenchymal transition, angiogenesis and chemoresistance. The present review focuses on previous studies addressing the exosome-dependent molecular transfer in peritoneal dissemination in gastric cancer and the potential clinical applications.

Binding of the GTPase Sar1 to a Lipid Membrane Monolayer: Insertion and Orientation Studied by Infrared Reflection⁻Absorption Spectroscopy.

Membrane-interacting proteins are polyphilic polymers that engage in dynamic protein–protein and protein–lipid interactions while undergoing changes in conformation, orientation and binding interfaces. Predicting the sites of interactions between such polypeptides and phospholipid membranes is still a challenge. One example is the small eukaryotic GTPase Sar1, which functions in phospholipid bilayer remodeling and vesicle formation as part of the multimeric coat protein complex (COPII). The membrane interaction of Sar1 is strongly dependent on its N-terminal 23 amino acids. By monolayer adsorption experiments and infrared reflection-absorption spectroscopy (IRRAS), we elucidate the role of lipids in inducing the amphipathicity of this N-terminal stretch, which inserts into the monolayer as an amphipathic helix (AH). The AH inserting angle is determined and is consistent with the philicities and spatial distribution of the amino acid monomers. Using an advanced method of IRRAS data evaluation, the orientation of Sar1 with respect to the lipid layer prior to the recruitment of further COPII proteins is determined. The result indicates that only a slight reorientation of the membrane-bound Sar1 is needed to allow coat assembly. The time-course of the IRRAS analysis corroborates a role of slow GTP hydrolysis in Sar1 desorption from the membrane.

Dual-functional drug liposomes in treatment of resistant cancers.

Efficacy of regular chemotherapy is significantly hampered by multidrug resistance (MDR) and severe systemic toxicity. The reduced toxicity has been evidenced after administration of drug liposomes, consisting of the first generation of regular drug liposomes, the second generation of long-circulation drug liposomes, and the third generation of targeting drug liposomes. However, MDR of cancers remains as an unsolved issue. The objective of this article is to review the dual-functional drug liposomes, which demonstrate the potential in overcoming MDR. Herein, dual-functional drug liposomes are referring to the drug-containing phospholipid bilayer vesicles that possess a dual-function of providing the basic efficacy of drug and the extended effect of the drug carrier. They exhibit unique roles in treatment of resistant cancer via circumventing drug efflux caused by adenosine triphosphate binding cassette (ABC) transporters, eliminating cancer stem cells, destroying mitochondria, initiating apoptosis, regulating autophagy, destroying supply channels, utilizing microenvironment, and silencing genes of the resistant cancer. As the prospect of an estimation, dual-functional drug liposomes would exhibit more strength in their extended function, hence deserving further investigation for clinical validation.

Liposomal Formulations in Clinical Use: An Updated Review.

Liposomes are the first nano drug delivery systems that have been successfully translated into real-time clinical applications. These closed bilayer phospholipid vesicles have witnessed many technical advances in recent years since their first development in 1965. Delivery of therapeutics by liposomes alters their biodistribution profile, which further enhances the therapeutic index of various drugs. Extensive research is being carried out using these nano drug delivery systems in diverse areas including the delivery of anti-cancer, anti-fungal, anti-inflammatory drugs and therapeutic genes. The significant contribution of liposomes as drug delivery systems in the healthcare sector is known by many clinical products, e.g., Doxil®, Ambisome®, DepoDur™, etc. This review provides a detailed update on liposomal technologies e.g., DepoFoam™ Technology, Stealth technology, etc., the formulation aspects of clinically used products and ongoing clinical trials on liposomes.