Novel methods for liposome preparation

Lipid loss and compositional change during preparation of liposomes by common biophysical methods

Liposomes are widely used as model lipid membrane platforms in many fields, ranging from basic biophysical studies to drug delivery and biotechnology applications. Various methods exist to prepare liposomes, but common procedures include thin-film hydration followed by extrusion, freeze-thaw, and/or sonication. These procedures have the potential to produce liposomes at specific concentrations and membrane compositions, and researchers often assume that the concentration and composition of their liposomes are similar to, if not identical, to what would be expected if no lipid loss occurred during preparation. However, lipid loss and concomitant biasing of lipid composition can in principle occur at any preparation step due to nonideal mixing, lipid-surface interactions, etc. Here, we report a straightforward method using HPLC-ELSD to quantify the lipid concentration and membrane composition of liposomes, and apply that method to study the preparation of simple POPC/cholesterol liposomes. We examine many common steps in liposome formation, including vortexing during re-suspension, hydration of the lipid film, extrusion, freeze-thaw, sonication, and the percentage of cholesterol in the starting mixture. We found that the resuspension step can play an outsized role in determining the overall lipid loss (up to ~50% under seemingly rigorous procedures). The extrusion step yielded smaller lipid losses (~10-20%). Freeze-thaw and sonication could both be employed to improve lipid yields. Hydration times up to 60 minutes and increasing cholesterol concentrations up to 50 mole% had little influence on lipid recovery. Fortunately, even conditions with large lipid loss did not substantially influence the target membrane composition more than ~5% under the conditions we tested. From our results, we identify best practices for producing maximum levels of lipid recovery and minimal changes to lipid composition during liposome preparation protocols. We expect our results can be leveraged for improved preparation of model membranes by researchers in many fields.

High Drug Capacity of Nano-Levodopa-Liposomes: Preparation, In Vitro Release and Brain-Targeted Research

In this work, nano-levodopa-liposomes (L-dopa-Lip) suspension was prepared by rotary-evaporated film-ultrasonic method, and freeze-drying powders of L-dopa-Lip were also obtained to improve the stability. The products were characterized by TEM, DLS, and TG-DSC, and the phase-transition temperature (Tm) and encapsulation efficiency were calculated. The brain-targeting and in vitro release of the drug was also studied. The results showed that L-dopa-Lip were well-formed spherical vesicles, and the sizes were about 100 nm, and the encapsulation efficiency was higher than 90%. The drug release temperature of L-dopa-Lip was 68 °C, and the in vitro release property and mathematical model were also studied. The brain targeting of L-dopa-Lip in vivo was explored by injecting the gold nanoparticles (AuNPs) labeled L-dopa-Lip (AuNPs-L-dopa-Lip) through the tail vein. ICP-MS and TEM showed that L-dopa-Lip had brain targeting, suggesting the potential treatment of L-dopa-Lip on brain dysfunction. The results of this work might be helpful for designing drug-loaded liposomes for the treatment of central nervous system (CNS) diseases and monitoring their distributions in vivo.

Advances in Nanoparticles in the Prevention and Treatment of Myocardial Infarction

Myocardial infarction (MI) is one of the most prevalent types of cardiovascular disease. During MI, myocardial cells become ischemic and necrotic due to inadequate blood perfusion, leading to irreversible damage to the heart. Despite the development of therapeutic strategies for the prevention and treatment of MI, their effects are still unsatisfactory. Nanoparticles represent a new strategy for the pre-treatment and treatment of MI, and novel multifunctional nanoparticles with preventive and therapeutic capabilities hold promise for the prevention and treatment of this disease. This review summarizes the common types and properties of nanoparticles, and focuses on the research progress of nanoparticles for the prevention and treatment of MI.

Innovative Delivery Systems for Curcumin: Exploring Nanosized and Conventional Formulations

Curcumin, a polyphenol with a rich history spanning two centuries, has emerged as a promising therapeutic agent targeting multiple signaling pathways and exhibiting cellular-level activities that contribute to its diverse health benefits. Extensive preclinical and clinical studies have demonstrated its ability to enhance the therapeutic potential of various bioactive compounds. While its reported therapeutic advantages are manifold, predominantly attributed to its antioxidant and anti-inflammatory properties, its efficacy is hindered by poor bioavailability stemming from inadequate absorption, rapid metabolism, and elimination. To address this challenge, nanodelivery systems have emerged as a promising approach, offering enhanced solubility, biocompatibility, and therapeutic effects for curcumin. We have analyzed the knowledge on curcumin nanoencapsulation and its synergistic effects with other compounds, extracted from electronic databases. We discuss the pharmacokinetic profile of curcumin, current advancements in nanoencapsulation techniques, and the combined effects of curcumin with other agents across various disorders. By unifying existing knowledge, this analysis intends to provide insights into the potential of nanoencapsulation technologies to overcome constraints associated with curcumin treatments, emphasizing the importance of combinatorial approaches in improving therapeutic efficacy. Finally, this compilation of study data aims to inform and inspire future research into encapsulating drugs with poor pharmacokinetic characteristics and investigating innovative drug combinations to improve bioavailability and therapeutic outcomes.

Current development of theragnostic nanoparticles for women's cancer treatment

In the biomedical industry, nanoparticles (NPs-exclusively small particles with size ranging from 1-100 nanometres) are recently employed as powerful tools due to their huge potential in sophisticated and enhanced cancer theragnostic (i.e. therapeutics and diagnostics). Cancer is a life-threatening disease caused by carcinogenic agents and mutation in cells, leading to uncontrolled cell growth and harming the body's normal functioning while affecting several factors like low levels of reactive oxygen species, hyperactive antiapoptotic mRNA expression, reduced proapoptotic mRNA expression, damaged DNA repair, and so on. NPs are extensively used in early cancer diagnosis and are functionalized to target receptors overexpressing cancer cells for effective cancer treatment. This review focuses explicitly on how NPs alone and combined with imaging techniques and advanced treatment techniques have been researched against 'women's cancer' such as breast, ovarian, and cervical cancer which are substantially occurring in women. NPs, in combination with numerous imaging techniques (like PET, SPECT, MRI, etc) have been widely explored for cancer imaging and understanding tumor characteristics. Moreover, NPs in combination with various advanced cancer therapeutics (like magnetic hyperthermia, pH responsiveness, photothermal therapy, etc), have been stated to be more targeted and effective therapeutic strategies with negligible side effects. Furthermore, this review will further help to improve treatment outcomes and patient quality of life based on the theragnostic application-based studies of NPs in women's cancer treatment.

Liposomes in the cosmetics: present and outlook

Liposomes are small spherical vesicles composed of phospholipid bilayers capable of encapsulating a variety of ingredients, including water- and oil-soluble compound, which are one of the most commonly used piggybacking and delivery techniques for many active ingredients and different compounds in biology, medicine and cosmetics. With the increasing number of active cosmetic ingredients, the concomitant challenge is to effectively protect, transport, and utilize these substances in a judicious manner. Many cosmetic ingredients are ineffective both topically and systemically when applied to the skin, thus changing the method of delivery and interaction with the skin of the active ingredients is a crucial step toward improving their effectiveness. Liposomes can improve the delivery of active ingredients to the skin, enhance their stability, and ultimately, improve the efficacy of cosmetics and and pharmaceuticals. In this review, we summarized the basic properties of liposomes and their recent advances of functionalities in cosmetics and and pharmaceuticals. Also, the current state of the art in the field is discussed and the prospects for future research areas are highlighted. We hope that this review will provide ideas and inspiration on the application and development of cosmetics and pharmaceuticals.

Advancements and prospects of lipid-based nanoparticles: dual frontiers in cancer treatment and vaccine development

Cancer is a complex heterogeneous disease that poses a significant public health challenge. In recent years, lipid-based nanoparticles (LBNPs) have expanded drug delivery and vaccine development options owing to their adaptable, non-toxic, tuneable physicochemical properties, versatile surface functionalisation, and biocompatibility. LBNPs are tiny artificial structures composed of lipid-like materials that can be engineered to encapsulate and deliver therapeutic agents with pinpoint accuracy. They have been widely explored in oncology; however, our understanding of their pharmacological mechanisms, effects of their composition, charge, and size on cellular uptake, tumour penetration, and how they can be utilised to develop cancer vaccines is still limited. Hence, we reviewed LBNPs' unique characteristics, biochemical features, and tumour-targeting mechanisms. Furthermore, we examined their ability to enhance cancer therapies and their potential contribution in developing anticancer vaccines. We critically analysed their advantages and challenges impeding swift advancements in oncology and highlighted promising avenues for future research.

Engineering aspects of lipid-based delivery systems: In vivo gene delivery, safety criteria, and translation strategies

Defects in the genome cause genetic diseases and can be treated with gene therapy. Due to the limitations encountered in gene delivery, lipid-based supramolecular colloidal materials have emerged as promising gene carrier systems. In their non-functionalized form, lipid nanoparticles often demonstrate lower transgene expression efficiency, leading to suboptimal therapeutic outcomes, specifically through reduced percentages of cells expressing the transgene. Due to chemically active substituents, the engineering of delivery systems for genetic drugs with specific chemical ligands steps forward as an innovative strategy to tackle the drawbacks and enhance their therapeutic efficacy. Despite intense investigations into functionalization strategies, the clinical outcome of such therapies still needs to be improved. Here, we highlight and comprehensively review engineering aspects for functionalizing lipid-based delivery systems and their therapeutic efficacy for developing novel genetic cargoes to provide a full snapshot of the translation from the bench to the clinics. We outline existing challenges in the delivery and internalization processes and narrate recent advances in the functionalization of lipid-based delivery systems for nucleic acids to enhance their therapeutic efficacy and safety. Moreover, we address clinical trials using these vectors to expand their clinical use and principal safety concerns.

Research Progress on Liposome Pulmonary Delivery of Mycobacterium tuberculosis Nucleic Acid Vaccine and Its Mechanism of Action

Traditional vaccines have played an important role in the prevention and treatment of infectious diseases, but they still have problems such as low immunogenicity, poor stability, and difficulty in inducing lasting immune responses. In recent years, the nucleic acid vaccine has emerged as a relatively cheap and safe new vaccine. Compared with traditional vaccines, nucleic acid vaccine has some unique advantages, such as easy production and storage, scalability, and consistency between batches. However, the direct administration of naked nucleic acid vaccine is not ideal, and safer and more effective vaccine delivery systems are needed. With the rapid development of nanocarrier technology, the combination of gene therapy and nanodelivery systems has broadened the therapeutic application of molecular biology and the medical application of biological nanomaterials. Nanoparticles can be used as potential drug-delivery vehicles for the treatment of hereditary and infectious diseases. In addition, due to the advantages of lung immunity, such as rapid onset of action, good efficacy, and reduced adverse reactions, pulmonary delivery of nucleic acid vaccine has become a hot spot in the field of research. In recent years, lipid nanocarriers have become safe, efficient, and ideal materials for vaccine delivery due to their unique physical and chemical properties, which can effectively reduce the toxic side effects of drugs and achieve the effect of slow release and controlled release, and there have been a large number of studies using lipid nanocarriers to efficiently deliver target components into the body. Based on the delivery of tuberculosis (TB) nucleic acid vaccine by lipid carrier, this article systematically reviews the advantages and mechanism of liposomes as a nucleic acid vaccine delivery carrier, so as to lay a solid foundation for the faster and more effective development of new anti-TB vaccine delivery systems in the future.

Effects of quercetin on the DNA methylation pattern in tumor therapy: an updated review

Quercetin is a unique bioactive flavonoid, and is an excellent antioxidant and has anti-tumor effects by regulating different tumor-related processes like proliferation, apoptosis, invasion, and spread. The latest investigations reveal that quercetin may have the capability to influence DNA methylation modification, one of the primary factors in the development of tumors. Despite the fact that quercetin has significant therapeutic properties, its use as an anti-tumor medicine is constrained by its poor solubility, short half-life, and ineffective tumor targeting. Here, we review the structure and properties of quercetin, its capacity for DNA methylation modification in tumors, and the possibility of nanoscale delivery of quercetin for future tumor treatment.

Recent Trends in Nanocarrier-Based Drug Delivery System for Prostate Cancer

Prostate cancer remains a significant global health concern, requiring innovative approaches for improved therapeutic outcomes. In recent years, nanoparticle-based drug delivery systems have emerged as promising strategies to address the limitations of conventional cancer chemotherapy. The key trends include utilizing nanoparticles for enhancing drug delivery to prostate cancer cells. Nanoparticles have some advantages such as improved drug solubility, prolonged circulation time, and targeted delivery of drugs. Encapsulation of chemotherapeutic agents within nanoparticles allows for controlled release kinetics, reducing systemic toxicity while maintaining therapeutic efficacy. Additionally, site-specific accumulation within the prostate tumor microenvironment is made possible by the functionalization of nanocarrier with targeted ligands, improving therapeutic effectiveness. This article highlights the basics of prostate cancer, statistics of prostate cancer, mechanism of multidrug resistance, targeting approach, and different types of nanocarrier used for the treatment of prostate cancer. It also includes the applications of nanocarriers for the treatment of prostate cancer and clinical trial studies to validate the safety and efficacy of the innovative drug delivery systems. The article focused on developing nanocarrier-based drug delivery systems, with the goal of translating these advancements into clinical applications in the future.

Development and optimization of a one step process for the production and sterilization of liposomes using supercritical CO2

Liposomes are very interesting drug delivery systems for pharmaceutical and therapeutic purposes. However, liposome sterilization as well as their industrial manufacturing remain challenging. Supercritical carbon dioxide is an innovative technology that can potentially overcome these limitations. The aim of this study was to optimize a one-step process for producing and sterilizing liposomes using supercritical CO2. For this purpose, a design of experiment was conducted. The analysis of the experimental design showed that the temperature is the most influential parameter to achieve the sterility assurance level (SAL) required for liposomes (≤10-6). Optimal conditions (80 °C, 240 bar, 30 min) were identified to obtain the fixed critical quality attributes of liposomes. The conditions for preparing and sterilizing empty liposomes of various compositions, as well as liposomes containing the poorly water-soluble drug budesonide, were validated. The results indicate that the liposomes have appropriate physicochemical characteristics for drug delivery, with a size of 200 nm or less and a PdI of 0.35 or less. Additionally, all liposome formulations demonstrated the required SAL and sterility at concentrations of 5 and 45 mM, with high encapsulation efficiency.

Niosome as a promising tool for increasing the effectiveness of anti-inflammatory compounds

Niosomes are drug delivery systems with widespread applications in pharmaceutical research and the cosmetic industry. Niosomes are vesicles of one or more bilayers made of non-ionic surfactants, cholesterol, and charge inducers. Because of their bilayer characteristics, similar to liposomes, niosomes can be loaded with lipophilic and hydrophilic cargos. Therefore, they are more stable and cheaper in preparation than liposomes. They can be classified into four categories according to their sizes and structures, namely small unilamellar vesicles (SUVs), large unilamellar vesicles (LUVs,), multilamellar vesicles (MLVs), and multivesicular vesicles (MVVs). There are many methods for niosome preparation, such as thin-film hydration, solvent injection, and heating method. The current study focuses on the preparation methods and pharmacological effects of niosomes loaded with natural and chemical anti-inflammatory compounds in kinds of literature during the past decade. We found that most research was carried out to load anti-inflammatory agents like non-steroidal anti-inflammatory drugs (NSAIDs) into niosome vesicles. The studies revealed that niosomes could improve anti-inflammatory agents' physicochemical properties, including solubility, cellular uptake, stability, encapsulation, drug release and liberation, efficiency, and oral bioavailability or topical absorption. See also the graphical abstract(Fig. 1).

Aptamer-Based Targeting of Cancer: A Powerful Tool for Diagnostic and Therapeutic Aims

Cancer is known as one of the most significant causes of death worldwide, and, in spite of novel therapeutic methods, continues to cause a considerable number of deaths. Targeted molecular diagnosis and therapy using aptamers with high affinity have become popular techniques for pathological angiogenesis and cancer therapy scientists. In this paper, several aptamer-based diagnostic and therapeutic techniques such as aptamer-nanomaterial conjugation, aptamer-drug conjugation (physically or covalently), and biosensors, which have been successfully designed for biomarkers, were critically reviewed. The results demonstrated that aptamers can potentially be incorporated with targeted delivery systems and biosensors for the detection of biomarkers expressed by cancer cells. Aptamer-based therapeutic and diagnostic methods, representing the main field of medical sciences, possess high potential for use in cancer therapy, pathological angiogenesis, and improvement of community health. The clinical use of aptamers is limited due to target impurities, inaccuracy in the systematic evolution of ligands via exponential enrichment (SELEX)stage process, and in vitro synthesis, making them unreliable and leading to lower selectivity for in vivo targets. Moreover, size, behavior, probable toxicity, low distribution, and the unpredictable behavior of nanomaterials in in vivo media make their usage in clinical assays critical. This review is helpful for the implementation of aptamer-based therapies which are effective and applicable for clinical use and the design of future studies.

Multi-vesicular Liposome and its Applications: A Novel Chemically Modified Approach for Drug Delivery Application

BACKGROUND

This study aimed to elaborate on all the aspects of multivesicular liposomes, including structure, function, topology, etc. Liposomes are a unique drug delivery system, in which both hydrophilic and hydrophobic drug molecules can be incorporated. Particularly, multivesicular liposomes have more advantages than other liposomes because of their unique structure. This study provides an overview of several works already performed by various researchers in this field. Numerous studies have reported on preparing and evaluating multivesicular liposomes for drug delivery applications. This study summarizes the process of formulating multivesicular liposomes and their application in drug delivery systems and provides details about how to resolve the problem of limited solubility and stability of biomolecules, along with controlled drug release kinetics, with the possibility of loading various drugs. There is no doubt that multivesicular liposome opens new avenues to develop novel drug delivery system for achieving the desired functional performances and expanding the applications in the drug delivery area.

Trophoblast-Targeted Liposomes for Placenta-Specific Drug Delivery

A major challenge in developing potential treatments for pregnancy complications is minimizing adverse effects to the fetus and mother. Placenta-targeted drug delivery could reduce the risks of drug treatments in pregnancy by targeting tissue where most pregnancy complications originate and decreasing dosages. We previously developed a tool for the targeted delivery of drug-carrying nanoparticles to the placenta using a synthetic placental chondroitin sulfate A-binding peptide (plCSA-BP) derived from the malarial protein VAR2CSA, which binds a distinct type of chondroitin sulfate A (CSA) exclusively expressed by placental trophoblasts. Liposomes are a type of nanoparticle already approved for use in humans by the Food and Drug Administration (FDA) and used successfully for the treatment of a wide range of diseases. Here, we present a detailed method to create plCSA-BP-decorated liposomes that can be used to deliver drugs specifically to placental trophoblasts. Liposomes are first generated by the standard film method and then conjugated to plCSA-BPs using the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysulfosuccinimide (EDC/NHS) bioconjugate technique. This protocol may facilitate bench-to-bedside translation of drug discovery for the treatment of pregnancy disorders by reducing risks of side effects, and enabling rapid and scalable production.

Indocyanine Green-Loaded Liposomes-Assisted Photoacoustic Computed Tomography for Evaluating In Vivo Tumor Penetration of Liposomal Nanocarriers

Liposomes possess the potential to enhance drug solubility, prolong the duration of circulation, and augment drug accumulation at the tumor site through passive and active targeting strategies. However, there is a lack of studies examining the in vivo tumor penetration capabilities of liposomes of varying sizes, which hampers the development of drug delivery systems utilizing liposomal nanocarriers. Here, we present an indocyanine green (ICG)-loaded liposomes-assisted photoacoustic computed tomography (PACT) for directly evaluating the tumor penetration ability of liposomal nanocarriers in vivo. Through the utilization of microfluidic mixing combined with extrusion techniques, we successfully prepare liposomes encapsulating ICG in both large (192.6 ± 8.0 nm) and small (61.9 ± 0.6 nm) sizes. Subsequently, we designed a dual-wavelength PACT system to directly monitor the in vivo tumor penetration of large- and small-size ICG-encapsulated liposomes. In vivo PACT experiments indicate that ICG-loaded liposomes of smaller size exhibit enhanced penetration capability within tumor tissues. Our work presents a valuable approach to directly assess the penetration ability of liposomal nanocarriers in vivo, thereby facilitating the advancement of drug delivery systems with enhanced tumor penetration and therapeutic efficacy.

Development of tLyP-1 functionalized nanoliposomes with tunable internal water phase for glioma targeting

tLyP-1 peptide is verified to recognize neuropilin (NRP) receptors overexpressed on the surface of both glioma cells and endothelial cells of angiogenic blood vessels. In the present study, tLyP-1 was conjugated with DSPE-PEG2000 to prepare tLyP-1-DSPE-PEG2000, which was further employed to prepare tLyP-1 functionalized nanoliposome (tLyP-1-Lip) to achieve enhancing target of glioblastoma. Process parameters were systematically studied to investigate the feasibility of tuning the internal water phase of nanoliposomes and encapsulating more Temozolomide (TMZ). The particle size, Zeta potential, and encapsulation efficiency of tLyP-1-Lip/TMZ were fully characterized in comparison with conventional nanoliposomes (Lip-TMZ) and PEGylated nanoliposomes (PEG-Lip/TMZ). The release behaviors of TMZ from PEG-Lip/TMZ and tLyP-1-Lip/TMZ are similar and slower than TMZ-Lip in acidic solutions. The tLyP-1-Lip/TMZ demonstrated the strongest cytotoxicity in comparison with TMZ-Lip and PEG-Lip/TMZ in both U87 and HT22 cells, and displayed the highest cellular internalization. The pharmacokinetic studies in rats revealed that tLyP-1-Lip/TMZ showed a 1.4-fold (p < 0.001) increase in AUCINF_obs and a 1.4-fold decrease (p < 0.01) in clearance compared with PEG-Lip/TMZ. We finally confirmed by in vivo imaging that tLyP-1-Lip were able to penetrate the brains and tumors of mice.

Specific surface modification of liposomes for gut targeting of food bioactive agents

Liposomes have become a research hotspot in recent years as food delivery systems with attractive properties, including the bilayer structure assembled like the cell membrane, reducing the side-effect and improving environmental stability of cargos, controlling release, extending duration of functional ingredients, and high biodegradable and biocompatible abilities in the body. However, the conventional liposomes lack stability during storage and are weak in targeted absorption in the gastrointestinal track. At present, surface modification has been approved to be an effective platform to shield these barricades and help liposomes deliver the agents safely and effectively to the ideal site. In this review, the gastrointestinal stability of conventional liposomes, cargo release models from liposomes, and the biological fate of the core materials after release were emphasized. Then, the strategies in both physical and chemical perspectives to improve the stability and utilization of liposomes in the gastrointestinal tract, and the emerging approaches for improving gut targeting by specifically modified liposomes and the intestinal receptors relative to liposomes/cargos absorption were highlighted. Last but not the least, the safety, challenges, and opportunities for the improvement of liposomal bioavailability were also discussed to inspire new applications of liposomes as oral carriers.

Therapeutic efficacy and pharmacokinetics of liposomal-cannabidiol injection: a pilot clinical study in dogs with naturally-occurring osteoarthritis

Introduction

Osteoarthritis is a common disease in dogs resulting in chronic pain and decreased wellbeing. Common analgesics such as non-steroidal anti-inflammatories may fail to control pain and can produce major adverse effects. Study objectives were to evaluate pharmacokinetics, therapeutic efficacy, and safety of subcutaneous liposomal-cannabidiol (CBD) as an additional analgesic therapy in dogs suffering from naturally-occurring osteoarthritis.

Methods

Six such dogs were recruited following ethics approval and owner consent. Dogs were administered a single subcutaneous injection of 5 mg/kg liposomal-CBD. Plasma concentrations of CBD, blood work, activity monitoring collar data, wellbeing questionnaire (owners) and pain scoring (veterinarian) were performed at baseline and monitored up to six weeks following intervention. Data overtime were compared with baseline using linear-regression mixed-effects. P-value was set at 0.05.

Results

CBD plasma concentrations were observed for 6 weeks; median (range) peak plasma concentration (Cmax) was 45.2 (17.8-72.5) ng/mL, time to Cmax was 4 (2-14) days and half-life was 12.4 (7.7-42.6) days. Median (range) collar activity score was significantly increased on weeks 5-6; from 29 (17-34) to 34 (21-38). Scores of wellbeing and pain evaluations were significantly improved at 2-3 weeks; from 69 (52-78) to 53.5 (41-68), and from 7.5 (6-8) to 5.5 (5-7), respectively. The main adverse effect was minor local swelling for several days in 5/6 dogs.

Conclusion

Liposomal-CBD administered subcutaneously produced detectable CBD plasma concentrations for 6 weeks with minimal side effects and demonstrated reduced pain and increased wellbeing as part of multimodal pain management in dogs suffering from osteoarthritis. Further placebo-controlled studies are of interest.

Antioxidant Activity of Quercetin-Containing Liposomes-in-Gel and Its Effect on Prevention and Treatment of Cutaneous Eczema

Cutaneous eczema is a kind of skin disease is characterized by inflammation. The main manifestations are various types of dermatitis, eczema, and urticaria. There are usually complications such as erythema, blisters, and epidermal peeling. The quercetin might have a therapeutic effect on cutaneous eczema due to its favorable antioxidant activity and anti-inflammatory effects. Currently, there are few studies on transdermal administration of antioxidant drugs for the treatment of cutaneous eczema. The aim of this study was to prepare quercetin-containing liposomes-in-gel (QU-LG), its antioxidant properties were evaluated, and it was used in the skin of mice suffering from dermal eczema to see if it had preventive and therapeutic effects in an attempt to make it a new option for the treatment of cutaneous eczema. QU-LG was prepared by the injection method to form the quercetin-containing liposomes (QU-L) and evenly dispersed in the natural dissolution of carboxymethylcellulose sodium (1%, CMC-Na). The release of QU-LG across the dialysis membranes was up to 30% and clearance of 1,1-diphenyl-2-picrylhydrazyl (DPPH) was 65.16 ± 3.513%. In anti-oxidation assay QU-LG inhibited malondialdehyde (MDA) production in liver better than the commercially available drug dexamethasone acetate cream. Compared with untreated mice, mice treated with QU-LG showed a statistically significant reduction in dermatopathologic symptoms. The results suggested that QU-LG had good antioxidant activity in vivo and in vitro and could be used for the prevention and treatment of cutaneous eczema.

Recent Progress of Preparation Strategies in Organic Nanoparticles for Cancer Phototherapeutics

Phototherapy has the advantages of being a highly targeted, less toxic, less invasive, and repeatable treatment, compared with conventional treatment methods such as surgery, chemotherapy, and radiotherapy. The preparation strategies are significant in order to determine the physical and chemical properties of nanoparticles. However, choosing appropriate preparation strategies to meet applications is still challenging. This review summarizes the recent progress of preparation strategies in organic nanoparticles, mainly focusing on the principles, methods, and advantages of nanopreparation strategies. In addition, typical examples of cancer phototherapeutics are introduced in detail to inform the choice of appropriate preparation strategies. The relative future trend and outlook are preliminarily proposed.

Rutin: Family Farming Products' Extraction Sources, Industrial Applications and Current Trends in Biological Activity Protection

In vitro and in vivo studies have demonstrated the bioactivity of rutin, a dietary flavonol naturally found in several plant species. Despite widespread knowledge of its numerous health benefits, such as anti-inflammatory, antidiabetic, hepatoprotective and cardiovascular effects, industrial use of rutin is still limited due to its low solubility in aqueous media, the characteristic bitter and astringent taste of phenolic compounds and its susceptibility to degradation during processing. To expand its applications and preserve its biological activity, novel encapsulation systems have been developed. This review presents updated research on the extraction sources and methodologies of rutin from fruit and vegetable products commonly found in a regular diet and grown using family farming approaches. Additionally, this review covers quantitative analysis techniques, encapsulation methods utilizing nanoparticles, colloidal and heterodisperse systems, as well as industrial applications of rutin.

Perspectives on cutting-edge nanoparticulate drug delivery technologies based on lipids and their applications

Numerous nanotech arenas in therapeutic biology have recently provided a scientific platform to manufacture a considerable swath of unique chemical entities focusing on drugs. Recently, nanoparticulate drug delivery systems have emerged to deliver a specific drug to a specified site. Among all other carriers, lipids possess features exclusive to nanostructured dosage forms. The bioavailability of orally administered drugs is typically negatively affected by their poor water solubility, resulting from the unique chemical moieties introduced. Because of their unique advantages, lipid nanoparticles must become increasingly predictable as a robust delivery mechanism. The enhanced biopharmaceutical properties and significance of lipid-based targeting technologies such as liposomes, niosomes, solid lipid nanoparticles and micelles are highlighted in this review. Pharmaceutical implications of lipid nanocarriers for the transport and distribution of various therapeutic agents, such as biotechnological products and small pharmaceutical molecules, is a booming topic. Lipid nanoparticles as drug delivery systems have many appealing properties, including high biocompatibility, ease of preparation, tissue specificity, avoidance of reticuloendothelial systems, delayed drug release, scale-up feasibility, nontoxicity and targeted delivery. The use of lipid nanoparticles to enhance the transport of biopharmaceuticals is currently considered state-of-the-art. Similarly, we critically examine the upcoming guidelines that therapeutic scientists should handle.

Lipid-based nanoparticles as drug delivery systems for cancer immunotherapy

Immune checkpoint inhibitors (ICIs) have shown remarkable success in cancer treatment. However, in cancer patients without sufficient antitumor immunity, numerous data indicate that blocking the negative signals elicited by immune checkpoints is ineffective. Drugs that stimulate immune activation-related pathways are emerging as another route for improving immunotherapy. In addition, the development of nanotechnology presents a promising platform for tissue and cell type-specific delivery and improved uptake of immunomodulatory agents, ultimately leading to enhanced cancer immunotherapy and reduced side effects. In this review, we summarize and discuss the latest developments in nanoparticles (NPs) for cancer immuno-oncology therapy with a focus on lipid-based NPs (lipid-NPs), including the characteristics and advantages of various types. Using the agonists targeting stimulation of the interferon genes (STING) transmembrane protein as an exemplar, we review the potential of various lipid-NPs to augment STING agonist therapy. Furthermore, we present recent findings and underlying mechanisms on how STING pathway activation fosters antitumor immunity and regulates the tumor microenvironment and provide a summary of the distinct STING agonists in preclinical studies and clinical trials. Ultimately, we conduct a critical assessment of the obstacles and future directions in the utilization of lipid-NPs to enhance cancer immunotherapy.

Mechanisms of theaflavins against gout and strategies for improving the bioavailability

BACKGROUND

Gout is a crystal related arthropathy caused by monosodium urate deposition. At present, the identification of appropriate treatments and new drugs to reduce serum uric acid levels and gout risk is a major research area.

PURPOSE

Theaflavins are naturally occurring compounds characterized by a benzodiazepine skeleton. The significant benefits of theaflavins have been well documented. A large number of studies have been carried out and excellent anti-gout results have been achieved in recent years.

STUDY DESIGN

A comprehensive analysis of the mechanism of the anti-gout effect of theaflavins is presented through a literature review and network pharmacology prediction, and strategies for increasing the bioavailability of theaflavins are summarized.

METHODS

In this review, the active components and pharmacological mechanisms of theaflavins in the treatment of gout were summarized, and the relationship between theaflavins and gout, the relevant components, and the potential mechanisms of anti-gout action were clarified by reviewing the literature on the anti-gout effects of theaflavins and network pharmacology.

RESULTS

Theaflavins exert anti-gout effects by down regulating the gene and protein expression of glucose transporter 9 (GLUT9) and uric acid transporter 1 (URAT1), while upregulating the mRNA expression levels of organic anion transporter 1 (OAT1), organic cation transporter N1 (OCTN1), organic cation transporters 1/2 (Oct1/2), and organic anion transporter 2 (OAT2). Network pharmacology prediction indicate that theaflavins can regulate the AGE-RAGE and cancer signaling pathways through ATP-binding cassette subfamily B member 1 (ABCB1), recombinant mitogen activated protein kinase 14 (MAPK14), telomerase reverse tranase (TERT), signal transducer and activator of transcription 1 (STAT1), matrix metalloproteinase 2 (MMP2), B-cell lymphoma-2 (BCL2), and matrix metalloproteinase 14 (MMP14) targets for anti-gout effects.

CONCLUSION

This review presents the mechanisms of anti-gout action of theaflavins and strategies for improving the bioavailability of theaflavins, as well as providing research strategies for anti-gout treatment measures and the development of novel anti-gout drugs.

Optimization of formulation and atomization of lipid nanoparticles for the inhalation of mRNA

Lipid nanoparticles (LNPs) have demonstrated efficacy and safety for mRNA vaccine administration by intramuscular injection; however, the pulmonary delivery of mRNA encapsulated LNPs remains challenging. The atomization process of LNPs will cause shear stress due to dispersed air, air jets, ultrasonication, vibrating mesh etc., leading to the agglomeration or leakage of LNPs, which can be detrimental to transcellular transport and endosomal escape. In this study, the LNP formulation, atomization methods and buffer system were optimized to maintain the LNP stability and mRNA efficiency during the atomization process. Firstly, a suitable LNP formulation for atomization was optimized based on the in vitro results, and the optimized LNP formulation was AX4, DSPC, cholesterol and DMG-PEG_2K at a 35/16/46.5/2.5 (%) molar ratio. Subsequently, different atomization methods were compared to find the most suitable method to deliver mRNA-LNP solution. Soft mist inhaler (SMI) was found to be the best for pulmonary delivery of mRNA encapsulated LNPs. The physico-chemical properties such as size and entrapment efficiency (EE) of the LNPs were further improved by adjusting the buffer system with trehalose. Lastly, the in vivo fluorescence imaging of mice demonstrated that SMI with proper LNPs design and buffer system hold promise for inhaled mRNA-LNP therapies.

Multifunctional magnetoliposomes as drug delivery vehicles for the potential treatment of Parkinson's disease

Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease. Therefore, development of novel technologies and strategies to treat PD is a global health priority. Current treatments include administration of Levodopa, monoamine oxidase inhibitors, catechol-O-methyltransferase inhibitors, and anticholinergic drugs. However, the effective release of these molecules, due to the limited bioavailability, is a major challenge for the treatment of PD. As a strategy to solve this challenge, in this study we developed a novel multifunctional magnetic and redox-stimuli responsive drug delivery system, based on the magnetite nanoparticles functionalized with the high-performance translocating protein OmpA and encapsulated into soy lecithin liposomes. The obtained multifunctional magnetoliposomes (MLPs) were tested in neuroblastoma, glioblastoma, primary human and rat astrocytes, blood brain barrier rat endothelial cells, primary mouse microvascular endothelial cells, and in a PD-induced cellular model. MLPs demonstrated excellent performance in biocompatibility assays, including hemocompatibility (hemolysis percentages below 1%), platelet aggregation, cytocompatibility (cell viability above 80% in all tested cell lines), mitochondrial membrane potential (non-observed alterations) and intracellular ROS production (negligible impact compared to controls). Additionally, the nanovehicles showed acceptable cell internalization (covered area close to 100% at 30 min and 4 h) and endosomal escape abilities (significant decrease in lysosomal colocalization after 4 h of exposure). Moreover, molecular dynamics simulations were employed to better understand the underlying translocating mechanism of the OmpA protein, showing key findings regarding specific interactions with phospholipids. Overall, the versatility and the notable in vitro performance of this novel nanovehicle make it a suitable and promising drug delivery technology for the potential treatment of PD.

Cell-Sized Lipid Vesicles as Artificial Antigen-Presenting Cells for Antigen-Specific T Cell Activation

In this study, efficient T cell activation is demonstrated using cell-sized artificial antigen-presenting cells (aAPCs) with protein-conjugated bilayer lipid membranes that mimic biological cell membranes. The highly uniform aAPCs are generated by a facile method based on standard droplet microfluidic devices. These aAPCs are able to activate the T cells in peripheral blood mononuclear cells, showing a 28-fold increase in interferon gamma (IFNγ) secretion, a 233-fold increase in antigen-specific CD8 T cells expansion, and a 16-fold increase of CD4 T cell expansion. The aAPCs do not require repetitive boosting or additional stimulants and can function at a relatively low aAPC-to-T cell ratio (1:17). The research presents strong evidence that the surface fluidity and size of the aAPCs are critical to the effective formation of immune synapses essential for T cell activation. The findings demonstrate that the microfluidic-generated aAPCs can be instrumental in investigating the physiological conditions and mechanisms for T cell activation. Finally, this method demonstrates the feasibility of customizable aAPCs for a cost-effective off-the-shelf approach to immunotherapy.

Theranostics Nanomedicine Applications for Colorectal Cancer and Metastasis: Recent Advances

Colorectal cancer (CRC) is the third most common cancer worldwide, and metastatic CRC is a fatal disease. The CRC-affected tissues show several molecular markers that could be used as a fresh strategy to create newer methods of treating the condition. The liver and the peritoneum are where metastasis occurs most frequently. Once the tumor has metastasized to the liver, peritoneal carcinomatosis is frequently regarded as the disease's final stage. However, nearly 50% of CRC patients with peritoneal carcinomatosis do not have liver metastases. New diagnostic and therapeutic approaches must be developed due to the disease's poor response to present treatment choices in advanced stages and the necessity of an accurate diagnosis in the early stages. Many unique and amazing nanomaterials with promise for both diagnosis and treatment may be found in nanotechnology. Numerous nanomaterials and nanoformulations, including carbon nanotubes, dendrimers, liposomes, silica nanoparticles, gold nanoparticles, metal-organic frameworks, core-shell polymeric nano-formulations, and nano-emulsion systems, among others, can be used for targeted anticancer drug delivery and diagnostic purposes in CRC. Theranostic approaches combined with nanomedicine have been proposed as a revolutionary approach to improve CRC detection and treatment. This review highlights recent studies, potential, and challenges for the development of nanoplatforms for the detection and treatment of CRC.

A Hitchhiker's Guide to Supplying Enzymatic Reducing Power into Synthetic Cells

The construction from scratch of synthetic cells by assembling molecular building blocks is unquestionably an ambitious goal from a scientific and technological point of view. To realize functional life-like systems, minimal enzymatic modules are required to sustain the processes underlying the out-of-equilibrium thermodynamic status hallmarking life, including the essential supply of energy in the form of electrons. The nicotinamide cofactors NAD(H) and NADP(H) are the main electron carriers fueling reductive redox reactions of the metabolic network of living cells. One way to ensure the continuous availability of reduced nicotinamide cofactors in a synthetic cell is to build a minimal enzymatic module that can oxidize an external electron donor and reduce NAD(P)+. In the diverse world of metabolism there is a plethora of potential electron donors and enzymes known from living organisms to provide reducing power to NAD(P)+ coenzymes. This perspective proposes guidelines to enable the reduction of nicotinamide cofactors enclosed in phospholipid vesicles, while avoiding high burdens of or cross-talk with other encapsulated metabolic modules. By determining key requirements, such as the feasibility of the reaction and transport of the electron donor into the cell-like compartment, we select a shortlist of potentially suitable electron donors. We review the most convenient proteins for the use of these reducing agents, highlighting their main biochemical and structural features. Noting that specificity toward either NAD(H) or NADP(H) imposes a limitation common to most of the analyzed enzymes, we discuss the need for specific enzymes─transhydrogenases─to overcome this potential bottleneck.

Lipocalin 2, synthesized using a cell-free protein synthesis system and encapsulated into liposomes, inhibits the adhesion of Porphyromonas gingivalis to human oral epithelial cells

BACKGROUND AND OBJECTIVE

Lipocalin 2 (LCN2), a glycoprotein expressed in epithelial cells and leukocytes, has an antibacterial effect and plays a role in innate immunity. The delivery of LCN2 encapsulated in liposomes to oral epithelium may be useful to prevent oral infectious diseases. This study aimed to investigate the inhibitory effect of LCN2, artificially synthesized using a cell-free protein synthesis (CFPS) system, on the adhesion of Porphyromonas gingivalis to oral epithelial cells in order to approach oral healthcare using LCN2.

METHODS

LCN 2 was synthesized using a CFPS system and assayed by Western blotting, mass spectrometry and enzyme-linked immunosorbent assay (ELISA). The bilayer liposomes were prepared by the spontaneous transfer method using 1,2-dioleoyl-sn-glycero-3 phosphocholine (DOPC), 3-sn-phosphatidylcholine from Egg Yolk (Egg-PC), and 1,2-dioleoyl-sn-glycero-3 phosphoethanolamine (DOPE). The cellular and medium fractions derived from the culture of oral epithelial cells with liposome-encapsulated LCN2 were assayed by Western blotting and ELISA. The effect of the synthesized LCN2 on adhesion of the labeled P. gingivalis to oral epithelial cells was investigated as an evaluation of its antibacterial activity.

RESULTS

The synthesized LCN2 protein was identified by Western blotting; its amino acid sequence was similar to that of recombinant LCN2 protein. The additions of DOPE and octa-arginine in the outer lipid-layer components of liposome significantly increased the delivery of liposomes to epithelial cells. When oral epithelial cells were cultured with the synthesized and liposome-encapsulated LCN2, LCN2 was identified in the cellular and medium fractions by Western blotting and its concentration in the cellular fraction from the culture with the synthesized LCN2 was significantly higher than that of a template DNA-free protein. The synthesized LCN2 and liposome-encapsulated LCN2 significantly inhibited the adhesion of P. gingivalis to oral epithelial cells compared with template DNA-free protein.

CONCLUSION

LCN2 was artificially synthesized by a CFPS system, encapsulated in liposomes, and delivered to oral epithelial cells, and demonstrated an antibacterial action against P. gingivalis. This approach may become a useful model for oral healthcare.

Liposomal stem cell extract formulation from Coffea canephora shows outstanding anti-inflammatory activity, increased tissue repair, neocollagenesis and neoangiogenesis

Coffea canephora plant stem cells can have bioactive compounds with tissue repairing and anti-inflammatory action. This study aimed to develop a liposomal stem cell extract formulation obtained from the leaves of C. canephora (LSCECC) and to investigate its capacity to contribute to the dynamic mechanisms of tissue repair. The liposome cream was developed and characterized through the dynamic light scattering technique, atomic force microscopy, and transmission electron microscopy. The excisional full-thickness skin wound model was used and daily topically treated with the LSCECC formulation or vehicle control. On days 2, 7, 14, and 21 after wounding, five rats from each group were euthanized and the rates of wound closure and re-epithelialization were evaluated using biochemical and histological tests. LSCECC resulted in faster re-epithelialization exhibiting a significant reduction in wound area of 36.4, 42.4, and 87.5% after 7, 10, and 14 days, respectively, when compared to vehicle control. LSCECC treated wounds exhibited an increase in granular tissue and a proper inflammatory response mediated by the reduction of pro-inflammatory cytokines like TNF-α and IL-6 and an increase of IL-10. Furthermore, wounds treated with LSCECC showed an increase in the deposition and organization of collagen fibers at the wound site and improved scar tissue quality due to the increase in transforming growth factor-beta and vascular endothelial growth factor. Our data showed that LSCECC improves wound healing, the formation of extracellular matrix, modulates inflammatory response, and promotes neovascularization being consider a promising bioactive extract to promote and support healthy skin. The graphical presents the action of LSCECC in all four phases of wound healing and tissue repair. The LSCECC can reduce the inflammatory infiltrate in the inflammatory phase by decreasing the pro-inflammatory cytokines like IL-6 and TNF-α, in addition to maintaining this modulation through lesser activation and recruitment of macrophages. The LSCECC can also increase the release of IL-10, an anti-inflammatory cytokine, decreasing local edema. The increase in VEGF provides neovascularization and the supply of nutrients to newly repaired tissue. Finally, signaling via TGF-β increases the production and organization of collagen fibers in the remodeling phase.

Precise control of liposome size using characteristic time depends on solvent type and membrane properties

Controlling the sizes of liposomes is critical in drug delivery systems because it directly influences their cellular uptake, transportation, and accumulation behavior. Although hydrodynamic focusing has frequently been employed when synthesizing nano-sized liposomes, little is known regarding how flow characteristics determine liposome formation. Here, various sizes of homogeneous liposomes (50-400 nm) were prepared according to flow rate ratios in two solvents, ethanol, and isopropyl alcohol (IPA). Relatively small liposomes formed in ethanol due to its low viscosity and high diffusivity, whereas larger, more poly-dispersed liposomes formed when using IPA as a solvent. This difference was investigated via numerical simulations using the characteristic time factor to predict the liposome size; this approach was also used to examine the flow characteristics inside the microfluidic channel. In case of the liposomes, the membrane rigidity also has a critical role in determining their size. The increased viscosity and packing density of the membrane by addition of cholesterol confirmed by fluorescence anisotropy and polarity lead to increase in liposome size (40-530 nm). However, the interposition of short-chain lipids de-aligned the bilayer membrane, leading to its degradation; this decreased the liposome size. Adding short-chain lipids linearly decreased the liposome size (130-230 nm), but at a shallower gradient than that of cholesterol. This analytical study expands the understanding of microfluidic environment in the liposome synthesis by offering design parameters and their relation to the size of liposomes.

Construction of redox-sensitive liposomes modified by glycyrrhetinic acid and evaluation of anti-hepatocellular carcinoma activity

The aim of this study was to construct a bifunctional liposome with hepatic-targeting capacity by modifying with a targeting ligand and an intracellular tumor reduction response functional group to deliver drugs precisely to focal liver tissues and release them in large quantities in hepatocellular carcinoma cells. This could improve drug efficacy and reduce toxic side effects at the same time. First, the bifunctional ligand for liposome was successfully obtained by chemically synthesizing it from the hepatic-targeting glycyrrhetinic acid (GA) molecule, cystamine, and the membrane component cholesterol. Then the ligand was used to modify the liposomes. The particle size, PDI and zeta potential of the liposomes were determined with a nanoparticle sizer, and the morphology was observed by transmission electron microscopy. The encapsulation efficiency and drug release behavior were also determined. Further, the stability in vitro of the liposomes and the changes in the simulated reducing environment were determined. Finally, the antitumor activity in vitro and cellular uptake efficiency of the drug-loaded liposomes were investigated by performing cellular assays. The results showed that the prepared liposomes had a uniform particle size of 143.6 ± 2.86 nm with good stability and an encapsulation rate of 84.3 ± 2.1 %. Moreover, the particle size of the liposomes significantly increased and the structure was destroyed in a DTT reducing environment. Cellular experiments showed that the modified liposoes had better cytotoxic effects on hepatocarcinoma cells than both normal liposomes and free drugs. This study has great potential for tumor therapy and provides novel ideas for the clinical use of oncology drugs in dosage forms.

Emerging Trends in Lipid-Based Vaccine Delivery: A Special Focus on Developmental Strategies, Fabrication Methods, and Applications

Lipid-based vaccine delivery systems such as the conventional liposomes, virosomes, bilosomes, vesosomes, pH-fusogenic liposomes, transferosomes, immuno-liposomes, ethosomes, and lipid nanoparticles have gained a remarkable interest in vaccine delivery due to their ability to render antigens in vesicular structures, that in turn prevents its enzymatic degradation in vivo. The particulate form of lipid-based nanocarriers confers immunostimulatory potential, making them ideal antigen carriers. Facilitation in the uptake of antigen-loaded nanocarriers, by the antigen-presenting cells and its subsequent presentation through the major histocompatibility complex molecules, leads to the activation of a cascade of immune responses. Further, such nanocarriers can be tailored to achieve the desired characteristics such as charge, size, size distribution, entrapment, and site-specificity through modifications in the composition of lipids and the selection of the appropriate method of preparation. This ultimately adds to its versatility as an effective vaccine delivery carrier. The current review focuses on the various lipid-based carriers that have been investigated to date as potential vaccine delivery systems, the factors that affect their efficacy, and their various methods of preparation. The emerging trends in lipid-based mRNA vaccines and lipid-based DNA vaccines have also been summarized.

Membrane Models and Experiments Suitable for Studies of the Cholesterol Bilayer Domains

Cholesterol (Chol) is an essential component of animal cell membranes and is most abundant in plasma membranes (PMs) where its concentration typically ranges from 10 to 30 mol%. However, in red blood cells and Schwann cells, PMs Chol content is as high as 50 mol%, and in the PMs of the eye lens fiber cells, it can reach up to 66 mol%. Being amphiphilic, Chol molecules are easily incorporated into the lipid bilayer where they affect the membrane lateral organization and transmembrane physical properties. In the aqueous phase, Chol cannot form free bilayers by itself. However, pure Chol bilayer domains (CBDs) can form in lipid bilayer membranes with the Chol content exceeding 50 mol%. The range of Chol concentrations surpassing 50 mol% is less frequent in biological membranes and is consequently less investigated. Nevertheless, it is significant for the normal functioning of the eye lens and understanding how Chol plaques form in atherosclerosis. The most commonly used membrane models are unilamellar and multilamellar vesicles (MLVs) and supported lipid bilayers (SLBs). CBDs have been observed directly using confocal microscopy, X-ray reflectometry and saturation recovery electron paramagnetic resonance (SR EPR). Indirect evidence of CBDs has also been reported by using atomic force microscopy (AFM) and fluorescence recovery after photobleaching (FRAP) experiments. The overall goal of this review is to demonstrate the advantages and limitations of the various membrane models and experimental techniques suitable for the detection and investigation of the lateral organization, function and physical properties of CBDs.

Unveiling growth and dynamics of liposomes by graphene liquid cell-transmission electron microscopy

Liposome is a model system for biotechnological and biomedical purposes spanning from targeted drug delivery to modern vaccine research. Yet, the growth mechanism of liposomes is largely unknown. In this work, the formation and evolution of phosphatidylcholine-based liposomes are studied in real-time by graphene liquid cell-transmission electron microscopy (GLC-TEM). We reveal important steps in the growth, fusion and denaturation of phosphatidylcholine (PC) liposomes. We show that initially complex lipid aggregates resembling micelles start to form. These aggregates randomly merge while capturing water and forming small proto-liposomes. The nanoscopic containers continue sucking water until their membrane becomes convex and free of redundant phospholipids, giving stabilized PC liposomes of different sizes. In the initial stage, proto-liposomes grow at a rate of 10-15 nm s^-1, which is followed by their growth rate of 2-5 nm s^-1, limited by the lipid availability in the solution. Molecular dynamics (MD) simulations are used to understand the structure of micellar clusters, their evolution, and merging. The liposomes are also found to fuse through lipid bilayers docking followed by the formation of a hemifusion diaphragm and fusion pore opening. The liposomes denaturation can be described by initial structural destabilization and deformation of the membrane followed by the leakage of the encapsulated liquid. This study offers new insights on the formation and growth of lipid-based molecular assemblies which is applicable to a wide range of amphiphilic molecules.

Skin drug delivery using lipid vesicles: A starting guideline for their development

Lipid vesicles can provide a cost-effective enhancement of skin drug absorption when vesicle production process is optimised. It is an important challenge to design the ideal vesicle, since their properties and features are related, as changes in one affect the others. Here, we review the main components, preparation and characterization methods commonly used, and the key properties that lead to highly efficient vesicles for transdermal drug delivery purposes. We stand by size, deformability degree and drug loading, as the most important vesicle features that determine the further transdermal drug absorption. The interest in this technology is increasing, as demonstrated by the exponential growth of publications on the topic. Although long-term preservation and scalability issues have limited the commercialization of lipid vesicle products, freeze-drying and modern escalation methods overcome these difficulties, thus predicting a higher use of these technologies in the market and clinical practice.

Optimization of detergents in solubilization and reconstitution of Aquaporin Z: A structural approach

BACKGROUND

The exceptional capacities of aquaporins in terms of water permeation and selectivity have made them an interesting system for membrane applications. Despite the multiple attempts for immobilizing the aquaporins over a porous substrate, there is a lack of studies related to the purification and reconstitution steps, principally associated with the use of detergents in solubilization and destabilization steps. This study analyzed the effect of detergents in Aquaporin Z solubilization, considering the purity and structural homogeneity of the protein.

METHODS

The extraction process was optimized by the addition of detergent at the sonication step, which enabled the omission of the ultracentrifugation and resuspension steps. Two detergents, Triton X-100, and octyl-glucoside were also evaluated. Destabilization mediated by detergents was used as reconstitution method. Saturation and solubilization points were defined by detergent concentration and both, liposomes and proteoliposomes, were analyzed by size distribution and permeability assays. Detergent removal with Bio-beads was also analyzed.

RESULTS

Octyl glucoside ensures structural stability and homogeneity of Aquaporin Z. However, high concentrations of detergents induce the presence of defects in proteoliposomes. While saturated liposomes create homogeneous and functional structures, solubilized liposomes get affected by a reassembly process, creating vesicle defects with anomalous permeability profiles.

CONCLUSIONS

Detergent concentration affects the structural conformation of proteoliposomes in the reconstitution process.

GENERAL SIGNIFICANCE

Since the destabilization process is dependent on vesicle, detergent, and buffer composition, optimization of this process should be mandatory for further studies. All these considerations will allow achieving the potential of Aquaporins and any other integral membrane protein in their applications for industrial purposes.

Current Advances in Lipid Nanosystems Intended for Topical and Transdermal Drug Delivery Applications

Skin delivery is an exciting and challenging field. It is a promising approach for effective drug delivery due to its ease of administration, ease of handling, high flexibility, controlled release, prolonged therapeutic effect, adaptability, and many other advantages. The main associated challenge, however, is low skin permeability. The skin is a healthy barrier that serves as the body's primary defence mechanism against foreign particles. New advances in skin delivery (both topical and transdermal) depend on overcoming the challenges associated with drug molecule permeation and skin irritation. These limitations can be overcome by employing new approaches such as lipid nanosystems. Due to their advantages (such as easy scaling, low cost, and remarkable stability) these systems have attracted interest from the scientific community. However, for a successful formulation, several factors including particle size, surface charge, components, etc. have to be understood and controlled. This review provided a brief overview of the structure of the skin as well as the different pathways of nanoparticle penetration. In addition, the main factors influencing the penetration of nanoparticles have been highlighted. Applications of lipid nanosystems for dermal and transdermal delivery, as well as regulatory aspects, were critically discussed.

An Overview of Drug Delivery Nanosystems for Sepsis-Related Liver Injury Treatment

Sepsis, which is a systemic inflammatory response syndrome caused by infection, has high morbidity and mortality. Sepsis-related liver injury is one of the manifestations of sepsis-induced multiple organ syndrome. To date, an increasing number of studies have shown that the hepatic inflammatory response, oxidative stress, microcirculation coagulation dysfunction, and bacterial translocation play extremely vital roles in the occurrence and development of sepsis-related liver injury. In the clinic, sepsis-related liver injury is mainly treated by routine empirical methods on the basis of the primary disease. However, these therapies have some shortcomings, such as serious side effects, short duration of drug effects and lack of specificity. The emergence of drug delivery nanosystems can significantly improve drug bioavailability and reduce toxic side effects. In this paper, we reviewed drug delivery nanosystems designed for the treatment of sepsis-related liver injury according to their mechanisms (hepatic inflammation response, oxidative stress, coagulation dysfunction in the microcirculation, and bacterial translocation). Although much promising progress has been achieved, translation into clinical practice is still difficult. To this end, we also discussed the key issues currently facing this field, including immune system rejection and single treatment modalities. Finally, with the rigorous optimization of nanotechnology and the deepening of research, drug delivery nanosystems have great potential for the treatment of sepsis-related liver injury.

Polymersome-based protein drug delivery - quo vadis?

Protein-based therapeutics are an attractive alternative to established therapeutic approaches and represent one of the fastest growing families of drugs. While many of these proteins can be delivered using established formulations, the intrinsic sensitivity of proteins to denaturation sometimes calls for a protective carrier to allow administration. Historically, lipid-based self-assembled structures, notably liposomes, have performed this function. After the discovery of polymersome-based targeted drug-delivery systems, which offer manifold advantages over lipid-based structures, the scientific community expected that such systems would take the therapeutic world by storm. However, no polymersome formulations have been commercialised. In this review article, we discuss key obstacles for the sluggish translation of polymersome-based protein nanocarriers into approved pharmaceuticals, which include limitations imparted by the use of non-degradable polymers, the intricacies of polymersome production methods, and the complexity of the in vivo journey of polymersomes across various biological barriers. Considering this complex subject from a polymer chemist's point of view, we highlight key areas that are worthy to explore in order to advance polymersomes to a level at which clinical trials become worthwhile and translation into pharmaceutical and nanomedical applications is realistic.

Neurogenic Hypertension, the Blood-Brain Barrier, and the Potential Role of Targeted Nanotherapeutics

Hypertension is a major health concern globally. Elevated blood pressure, initiated and maintained by the brain, is defined as neurogenic hypertension (NH), which accounts for nearly half of all hypertension cases. A significant increase in angiotensin II-mediated sympathetic nervous system activity within the brain is known to be the key driving force behind NH. Blood pressure control in NH has been demonstrated through intracerebrovascular injection of agents that reduce the sympathetic influence on cardiac functions. However, traditional antihypertensive agents lack effective brain permeation, making NH management extremely challenging. Therefore, developing strategies that allow brain-targeted delivery of antihypertensives at the therapeutic level is crucial. Targeting nanotherapeutics have become popular in delivering therapeutics to hard-to-reach regions of the body, including the brain. Despite the frequent use of nanotherapeutics in other pathological conditions such as cancer, their use in hypertension has received very little attention. This review discusses the underlying pathophysiology and current management strategies for NH, as well as the potential role of targeted therapeutics in improving current treatment strategies.

Cell-mimicking polyethylene glycol-diacrylate based nanolipogel for encapsulation and delivery of hydrophilic biomolecule

Lipid based nanoparticulate formulations have been widely used for the encapsulation and sustain release of hydrophilic drugs, but they still face challenges such as high initial burst release. Nanolipogel (NLG) emerges as a potential system to encapsulate and deliver hydrophilic drug while suppressing its initial burst release. However, there is a lack of characterization of the drug release mechanism from NLGs. In this work, we present a study on the release mechanism of hydrophilic Dextran-Fluorescein Isothiocyanate (DFITC) from Poly (ethylene glycol) Diacrylate (PEGDA) NLGs by using different molecular weights of PEGDA to vary the mesh size of the nanogel core, drawing inspiration from the macromolecular crowding effect in cells, which can be viewed as a mesh network of undefined sizes. The effect is then further characterized and validated by studying the diffusion of DFITC within the nanogel core using Fluorescence Recovery after Photobleaching (FRAP), on our newly developed cell derived microlipogels (MLG). This is in contrast to conventional FRAP works on cells or bulk hydrogels, which is limited in our application. Our work showed that the mesh size of the NLGs can be controlled by using different Mw of PEGDA, such as using a smaller MW to achieve higher crosslinking density, which will lead to having smaller mesh size for the crosslinked nanogel, and the release of hydrophilic DFITC can be sustained while suppressing the initial burst release, up to 10-fold more for crosslinked PEGDA 575 NLGs. This is further validated by FRAP which showed that the diffusion of DFITC is hindered by the decreasing mesh sizes in the NLGs, as a result of lower mobile fractions. These findings will be useful for guiding the design of PEGDA NLGs to have different degree of suppression of the initial burst release as well as the cumulative release, for a wide array of applications. This can also be extended to other different types of nanogel cores and other nanogel core-based nanoparticles for encapsulation and release of hydrophilic biomolecules.

Liposomes or Extracellular Vesicles: A Comprehensive Comparison of Both Lipid Bilayer Vesicles for Pulmonary Drug Delivery

The rapid and non-invasive pulmonary drug delivery (PDD) has attracted great attention compared to the other routes. However, nanoparticle platforms, like liposomes (LPs) and extracellular vesicles (EVs), require extensive reformulation to suit the requirements of PDD. LPs are artificial vesicles composed of lipid bilayers capable of encapsulating hydrophilic and hydrophobic substances, whereas EVs are natural vesicles secreted by cells. Additionally, novel LPs-EVs hybrid vesicles may confer the best of both. The preparation methods of EVs are distinguished from LPs since they rely mainly on extraction and purification, whereas the LPs are synthesized from their basic ingredients. Similarly, drug loading methods into/onto EVs are distinguished whereby they are cell- or non-cell-based, whereas LPs are loaded via passive or active approaches. This review discusses the progress in LPs and EVs as well as hybrid vesicles with a special focus on PDD. It also provides a perspective comparison between LPs and EVs from various aspects (composition, preparation/extraction, drug loading, and large-scale manufacturing) as well as the future prospects for inhaled therapeutics. In addition, it discusses the challenges that may be encountered in scaling up the production and presents our view regarding the clinical translation of the laboratory findings into commercial products.

What We Need to Know about Liposomes as Drug Nanocarriers: An Updated Review

Liposomes have been attracted considerable attention as phospholipid spherical vesicles, over the past 40 years. These lipid vesicles are valued in biomedical application due to their ability to carry both hydrophobic and hydrophilic agents, high biocompatibility and biodegradability. Various methods have been used for the synthesis of liposomes, so far and numerous modifications have been performed to introduce liposomes with different characteristics like surface charge, size, number of their layers, and length of circulation in biological fluids. This article provides an overview of the significant advances in synthesis of liposomes via active or passive drug loading methods, as well as describes some strategies developed to fabricate their targeted formulations to overcome limitations of the "first-generation" liposomes.

Comparison of different types of liposomal nano structures for microRNA transfection to human mesenchymal stem cell line S1939

Background: Liposomes are utilized as a drug delivery carrier in various fields of biomedicine. They are synthesized in the nanometer-size range and are becoming a viable drug delivery carrier for the treatment of different diseases. MicroRNAs as regulatory elements could be transferred to cells for changing their morphology or physiology. The study's major aim is to find the optimized formula of liposomes for transfection of microRNA to human mesenchymal stem cell line S1939 (HMSCs). Materials and Methods: Various ratios of soybean phosphatidylcholine (SPC), cholesterol, 1, 2 dioleoyloxy-3- (trimethylammonium) propane (DOTAP), and polyethylene glycol (PEG) were combined. The mean diameter of all formulations and their surface properties were determined by a zeta sizer device and scanning electron microscope, respectively. The cytotoxicity of formulations was assessed using MTT (3,4,5-dimethyl thiazol-2-yl) (2,5-diphenyltetrazolium bromide) assay. The transfection effectiveness of liposomal miRNA vs empty liposomes was determined using agarose gel electrophoresis. Results: The optimized liposome vesicles were prepared using 45:30:27.5:5 molar ratios of SPC:DOTAP:cholesterol: DSPE-PEG. The liposome formulations F10 and F18 were the best in terms of biocompatibility because of the higher viabilities of treated cells. The best formulation (F18, containing 0.7 µg of miRNA and 10 µg of liposome) was nearly 100% efficient in sequestering and fixing miRNA. Phase-contrast and fluorescent microscopic examinations showed intra-nuclear as well as intracytoplasmic localization of the particles. Conclusion: Some easily prepared liposomal formulation vehicles are quite efficient in the transfection of miRNA into the HMSCs and could be used for in vitro applications in regenerative medicine.

Encapsulation of Vitamins Using Nanoliposome: Recent Advances and Perspectives

Nowadays the importance of vitamins is clear for everyone. However, many patients are suffering from insufficient intake of vitamins. Incomplete intake of different vitamins from food sources due to their destruction during food processing or decrease in their bioavailability when mixing with other food materials, are factors resulting in vitamin deficiency in the body. Therefore, various lipid based nanocarriers such as nanoliposomes were developed to increase the bioavailability of bioactive compounds. Since the function of nanoliposomes containing vitamins on the body has a direct relationship with the quality of produced nanoliposomes, this review study was planned to investigate the several aspects of liposomal characteristics such as size, polydispersity index, zeta potential, and encapsulation efficiency on the quality of synthesized vitamin-loaded nanoliposomes.