Liposomal Formulation Research Articles

MiRNA‐21 Inhibitor‐Loaded Cationic Liposomes Development using the Quality by Design Approach

AbstractThe success of efficiently delivering genetic material to target cells depends on developing an appropriate vector. Among the variety of nanocarriers used for gene therapy, cationic liposomes are the most investigated for delivering genetic material in different forms of cancer. Cationic liposomes contain lipids with positively charged head groups that form electrostatic bonds with the negatively charged phosphate group of nucleic acids, ensuring efficient loading of the genetic material. The aim of this study was the development and in vitro characterization of liposomal formulations for genetic material delivery using the Quality by Design (QbD) approach. We have employed the Design of Experiments (DoE) methodology to study the impact of selected formulation factors on the quality of the proposed non‐viral vectors. Among the varied factors, the ones that had an impact on the responses were the total lipid concentration and cationic lipid concentration. Two liposomal formulations with adequate critical quality attributes (CQAs) were selected for miRNA‐21 inhibitor encapsulation. We continued with the in vitro evaluation on lung cancer cell line. Fluorescence microscopy helped visualize the internalization of all liposomal formulations and apoptotic effects. Finally, we evaluated the cellular viability and migration events after treatment with the cationic liposomes.

Targeting of M2 macrophages with IL-13-functionalized liposomal prednisolone inhibits melanoma angiogenesis in vivo

The intricate cooperation between cancer cells and nontumor stromal cells within melanoma microenvironment (MME) enables tumor progression and metastasis. We previously demonstrated that the interplay between tumor-associated macrophages (TAMs) and melanoma cells can be disrupted by using long-circulating liposomes (LCLs) encapsulating prednisolone phosphate (PLP) (LCL-PLP) that inhibited tumor angiogenesis coordinated by TAMs. In this study, our goal was to improve LCL specificity for protumor macrophages (M2-like (i.e., TAMs) macrophages) and to induce a more precise accumulation at tumor site by loading PLP into IL-13-conjugated liposomes (IL-13-LCL-PLP), since IL-13 receptor is overexpressed in this type of macrophages. The IL-13-LCL-PLP liposomal formulation was obtained by covalent attachment of thiolated IL-13 to maleimide-functionalized LCL-PLP. C57BL/6 mice bearing B16.F10 s.c melanoma tumors were used to investigate the antitumor action of LCL-PLP and IL-13-LCL-PLP. Our results showed that IL-13-LCL-PLP formulation remained stable in biological fluids after 24h and it was preferentially taken up by M2 polarized macrophages. IL-13-LCL-PLP induced strong tumor growth inhibition compared to nonfunctionalized LCL-PLP at the same dose, by altering TAMs-mediated angiogenesis and oxidative stress, limiting resistance to apoptosis and invasive features in MME. These findings suggest IL-13-LCL-PLP might become a promising delivery platform for chemotherapeutic agents in melanoma.

Phitosomin drug and its use in poultry farming

Solving the problem of normalizing metabolic processes and the morphological and functional state of the liver in poultry through the use of pharmacological agents seems to be an important reserve for increasing the effi ciency of industrial poultry farming and food production. Promising in this regard are studies on the development of medicines based on plant resources, which are characterized by structural diversity, multifunctionality of pharmacological action and low toxicity. The purpose of the research was to develop the liposomal drug Phitosomin, study its pharmacological and toxicological properties and substantiate the eff ectiveness of its use in poultry farming. Biopharmaceutical research has been carried out to develop a liposomal drug for veterinary use with a multifunctional pharmacological eff ect. The component composition of the drug Phitosomin represented by lecithin, dihydroquercetin, extracts of milk thistle, common agrimony and hare’s-ear, has been substantiated. A liposomal dosage form of the drug has been developed. Its physicochemical properties and shelf life have been established. The toxicological characteristics of the drug Phitosomin were studied, which made it possible to determine the degree of safety of its use in rearing of broiler chickens. Data were obtained experimentally on the pharmacological eff ects of Phitosomin on laboratory animals and broiler chickens when modeling various pathologies. The pharmacodynamic eff ect of the drug on blood parameters and productive traits of broiler chickens has been established, and the eff ective dose of its use in rearing broiler chickens has been determined. It was established as a result of the production inspection that when Phitosomin was introduced into the main diet of poultry of the experimental group at a dose of 5 g/kg of feed during the growth and finishing periods of feeding, there was an increase in the live weight of broiler chickens by 12,6 % and the livability of livestock by 1,6 abs.% compare with the control group.

Intrinsic immunogenicity of liposomes for tuberculosis vaccines: Effect of cationic lipid and cholesterol

Tuberculosis (TB) is still among the deadliest infectious diseases, hence there is a pressing need for more effective TB vaccines. Cationic liposome subunit vaccines are excellent vaccine candidates offering effective protection with a better safety profile than live vaccines. In this study, we aim to explore intrinsic adjuvant properties of cationic liposomes to maximize immune activation while minimizing aspecific cytotoxicity. To achieve this, we developed a rational strategy to select liposomal formulation compositions and assessed their physicochemical and immunological properties in vitro models using human monocyte-derived dendritic cells (MDDCs). A broad selection of commercially available cationic compounds was tested to prepare liposomes containing Ag85B-ESAT6-Rv2034 (AER) fusion protein antigen. 1,2-Dioleoyl-sn‑glycero-3-ethylphosphocholine (EPC)-based liposomes exhibited the most advantageous activation profile in MDDCs as assessed by cell surface activation markers, cellular uptake, antigen-specific T-cell activation, cytokine production, and cellular viability. The addition of cholesterol to 20 mol% improved the performance of the tested formulations compared to those without it; however, when its concentration was doubled there was no further benefit, resulting in reduced cell viability. This study provides new insights into the role of cationic lipids and cholesterol in liposomal subunit vaccines.

Exploring the Antimelanoma Potential of Betulinic Acid Esters and Their Liposomal Nanoformulations

Betulinic acid is a naturally occurring pentacyclic triterpene belonging to the lupane-group that exhibits a wide range of pharmacological activities. BA derivatives are continuously being researched due to their improved anticancer efficacy and bioavailability. The current research was conducted in order to determine the antiproliferative potential of three synthesized BA fatty esters using palmitic, stearic and butyric acids and their liposomal nanoformulations. The cytotoxic potential of BA fatty esters (Pal-BA, St-BA, But-BA) and their respective liposomal formulations (Pal-BA-Lip, St-BA-Lip, But-BA-Lip) has been assessed on HaCaT immortalized human keratinocytes and A375 human melanoma cells. Both the esters and their liposomes acted as cytotoxic agents against melanoma cells in a time- and dose-dependent manner. The butyryl ester But-BA outperformed BA in terms of cytotoxicity (IC50 60.77 μM) while the nanoformulations St-BA-Lip, But-BA-Lip and BA-Lip also displayed IC50 values (60.11, 50.71 and 59.01 μM) lower compared to BA (IC50 65.9 μM). The morphological evaluation revealed that the A375 cells underwent morphological changes consistent with apoptosis following 48 h treatment with the tested compounds, while the HaCaT cells’ morphology remained unaltered. Both the esters and their liposomal formulations were able to inhibit the migration of the melanoma cells, suggesting a significant antimetastatic effect. The quantitative real-time PCR revealed that all tested samples were able to significantly increase the expression of the pro-apoptotic Bax and inhibit the anti-apoptotic Bcl-2 proteins. This effect was more potent in the case of liposomal nanoformulations versus non-encapsulated compounds, and overall, But-BA and its formulation exhibited the best results in this regard.

Electroformation of giant unilamellar vesicles from large liposomes

AbstractGiant unilamellar vesicles (GUVs) are widely used as model systems for biological membranes to study membrane-related processes in a precisely controlled in vitro environment, owing to their biophysical properties. The classical technique for the formation of giant liposomes starts with the dissolution of lipids or lipid mixtures in an organic solvent, which is then deposited as a thin lipid solution film on a support substrate. In this study, we present a comprehensive analysis investigating the effect of different lipid compositions on the generation of GUVs from preformed liposomes under non-ionic and ionic conditions. For all liposome types tested, the electroformation process, whether performed on indium tin oxide-coated glass slides or platinum wires, consistently produced GUVs that typically ranged in size from 5 to 20 μm. However, the yield of GUVs varied depending on the specific non-ionic or ionic conditions and the lipid composition of the preformed liposomes used. In general, the resulting population of giant vesicles was predominantly characterised by the presence of unilamellar and multivesicular vesicles. These findings have the potential to improve the refinement of protocol parameters for the formation of GUVs containing membrane proteins and for the study of the effects of lipid composition on membrane protein activity.

Targeting of focal adhesion kinase enhances the immunogenic cell death of PEGylated liposome doxorubicin to optimize therapeutic responses of immune checkpoint blockade

BackgroundsImmune checkpoint blockade (ICB) is widely considered to exert long-term treatment benefits by activating antitumor immunity. However, many cancer patients show poor clinical responses to ICB due in part to the lack of an immunogenic niche. Focal adhesion kinase (FAK) is frequently amplified and acts as an immune modulator across cancer types. However, evidence illustrates that targeting FAK is most effective in combination therapy rather than in monotherapy.MethodsHere, we used drug screening, in vitro and in vivo assays to filter out that doxorubicin and its liposomal form pegylated liposome doxorubicin (PLD) showed synergistic anti-tumor effects in combination with FAK inhibitor IN10018. We hypothesized that anti-tumor immunity and immunogenic cell death (ICD) may be involved in the treatment outcomes through the data analysis of our clinical trial testing the combination of IN10018 and PLD. We then performed cell-based assays and animal studies to detect whether FAK inhibition by IN10018 can boost the ICD of PLD/doxorubicin and further established syngeneic models to test the antitumor effect of triplet combination of PLD, IN10018, and ICB.ResultsWe demonstrated that the combination of FAK inhibitor IN10018, and PLD/doxorubicin exerted effective antitumor activity. Notably, the doublet combination regimen exhibited response latency and long-lasting treatment effects clinically, outcomes frequently observed in immunotherapy. Our preclinical study confirmed that the 2-drug combination can maximize the ICD of cancer cells. This approach primed the tumor microenvironment, supplementing it with sufficient tumor-infiltrating lymphocytes (TILs) to activate antitumor immunity. Finally, different animal studies confirmed that the antitumor effects of ICB can be significantly enhanced by this doublet regimen.ConclusionsWe confirmed that targeting FAK by IN10018 can enhance the ICD of PLD/doxorubicin, further benefiting the anti-tumor effect of ICB. The animal tests of the triplet regimen warrant further discovery in the real world.

Liposomal Formulation Reduces Transport and Cell Uptake of Colistin in Human Lung Epithelial Calu-3 Cell and 3D Human Lung Primary Tissue Models.

Respiratory tract infections caused by multi-drug-resistant (MDR) bacteria have been a severe risk to human health. Colistin is often used to treat the MDR Gram-negative bacterial infections as a last-line therapy. Inhaled colistin can achieve a high concentration in the lung but none of aerosolized colistin products has been approved in the USA. Liposome has been reported as an advantageous formulation strategy for antibiotics due to its controlled release profile and biocompatibility. We have developed colistin liposomal formulations in our previous study. In the present study, the cellular uptake and transport of colistin in colistin liposomes were examined in two human lung epithelium in vitro models, Calu-3 monolayer and EpiAirway 3D tissue models. In both models, cellular uptake (p < 0.05) and cellular transport (p < 0.01) of colistin were significantly reduced by the colistin liposome compared to the colistin solution. Our findings indicate that inhaled colistin liposomes could be a promising treatment for extracellular bacterial lung infections caused by MDR Pseudomonas aeruginosa (P. aeruginosa).

Enhancing Solubility and Bioefficacy of Stilbenes by Liposomal Encapsulation-The Case of Macasiamenene F.

Stilbenes in food and medicinal plants have been described as potent antiphlogistic and antioxidant compounds, and therefore, they present an interesting potential for the development of dietary supplements. Among them, macasiamenene F (MF) has recently been shown to be an effective anti-inflammatory and cytoprotective agent that dampens peripheral and CNS inflammation in vitro. Nevertheless, this promising molecule, like other stilbenes and a large percentage of drugs under development, faces poor water solubility, which results in trickier in vivo administration and low bioavailability. With the aim of improving MF solubility and developing a form optimized for in vivo administration, eight types of conventional liposomal nanocarriers and one type of PEGylated liposomes were formulated and characterized. In order to select the appropriate form of MF encapsulation, the safety of MF liposomal formulations was evaluated on THP-1 and THP-1-XBlue-MD2-CD14 monocytes, BV-2 microglia, and primary cortical neurons in culture. Furthermore, the cellular uptake of liposomes and the effect of encapsulation on MF anti-inflammatory effectiveness were evaluated on THP-1-XBlue-MD2-CD14 monocytes and BV-2 microglia. MF (5 mol %) encapsulated in PEGylated liposomes with an average size of 160 nm and polydispersity index of 0.122 was stable, safe, and the most promising form of MF encapsulation keeping its cytoprotective and anti-inflammatory properties.

Cardamonin-loaded liposomal formulation for improving percutaneous penetration and follicular delivery for androgenetic alopecia.

Androgenic alopecia (AGA) has a considerable impact on the physical and mental health of patients. Nano preparations have apparent advantages and high feasibility in the treatment of AGA. Cardamonin (CAR) has a wide range of pharmacological activities, but it has the problems of poor solubility in water and low bioavailability. There are few, if any, researches on the use of nano-loaded CAR to improve topical skin delivery of AGA. In this study, a CAR-loaded liposomal formulation (CAR@Lip and CAR@Lip Gel) was developed and characterized. The prepared CAR@Lip exhibited a uniform and rounded vesicle in size. CAR@Lip and CAR@Lip Gel can significantly improve the cumulative release of CAR. Additionally, CAR@Lip can obviously promote the proliferation and migration of human dermal papilla cells (hDPCs). Cell uptake revealed that the uptake of CAR@Lip significantly increased compared with the free drug. Furthermore, both CAR@Lip and CAR@Lip Gel groups could markedly improve the transdermal performance of CAR, and increase the topical content of the drug in the hair follicle compared with CAR. The ratchet effect of hair follicles could improve the skin penetration depth of nanoformulations. Notably, Anti-AGA tests in the mice showed that CAR@Lip and CAR@Lip Gel groups could promote hair growth, and accelerate the transition of hair follicles to the growth stage. The anti-androgen effect was revealed by regulating the expression of IGF-1, VEGF, KGF, and TGF-β, participating in SHH/Gli and Wnt/β-catenin pathways. Importantly, the nanoformulations had no obvious skin irritation. Thus, our study showed that CAR-loaded liposomal formulation has potential application in the treatment of AGA.

Preparation and in vitro evaluation of BBG-250 loaded liposomal formulation for anticancer potential

BackgroundLiposome-mediated drug delivery systems have emerged as a promising avenue for enhancing cancer treatment strategies. This study aims to develop and assess liposomal carriers loaded with Brilliant Blue G-250 (BBG-250), a potent P2X7 receptor antagonist that shows potential as an anti-tumor agent. Specifically, two types of liposomal formulations were designed: conventional liposomes composed of hydrogenated soya phosphatidylcholine (HSPC) and cholesterol, and pH-sensitive liposomes consisting of dioleoylphosphatidylethanolamine (DOPE), distearoylphosphatidylethanolamine-methoxy polyethylene glycol (DSPE-mPEG), dipalmitoylphosphatidylcholine (DPPC), and cholesterol. The investigation focuses on understanding the morphological characteristics, size, stability, drug incorporation efficiency, drug release profiles, blood compatibility, and cytotoxicity of these liposomal formulations.ResultsAdvanced photon correlation spectroscopy using the Nano Plus-3 instrument was employed to evaluate the liposomes. The optimized conventional liposomes (HSPC-cholesterol ratio 7:3) exhibited a size of 125 ± 0.3 nm with a polydispersity index (PDI) of 0.21, indicating uniformity. The pH-sensitive liposomes (DOPE:DPPC:DSPE-PEG2000: Cholesterol 4:3:3:0.3) demonstrated a size of 118 ± 1.2 nm with a PDI of 0.230. Zeta potential measurements confirmed the stability of both formulations under physiological conditions, with values of − 16.93 mV for conventional liposomes and − 25.21 mV for pH-sensitive liposomes. Higher drug-to-lipid ratios were found to enhance drug incorporation efficiency. pH-sensitive liposomes exhibited superior drug release characteristics, with 95% release over 24 h, compared to conventional liposomes, which released 70% of the drug. Blood compatibility assessments revealed the safety of both formulations for intravenous administration. Cytotoxicity studies conducted on A549 cell lines demonstrated the cytocompatibility of both liposomal types across a range of concentrations, with IC50 values surpassing those of the reference drug, docetaxel.ConclusionsThis study underscores the potential of liposomal carriers as effective vehicles for delivering BBG-250, highlighting their stability, biocompatibility, and controlled drug release properties. Despite being slightly less potent than the reference drug, docetaxel, these liposomal formulations hold promise for advancing anticancer strategies. The findings contribute to the evolving landscape of innovative cancer therapy drug delivery systems, offering a novel approach to improving treatment outcomes for cancer patients. The successful development and evaluation of these liposomal carriers pave the way for further investigations and potential clinical applications in the field of cancer therapeutics.

Liposomal formulations of Oleae europaea L.: analyzing the antioxidant and antidiabetic activities along with toxicity profile in pancreatic beta TC6 cell line

ABSTRACT Olea europaea L. (Oleaceae), is rich in phenolic content and has powerful antioxidant and antidiabetic activity. However, there are no medicinal products prepared due to this feature. Therefore, this study aims to characterize an O. europaea extract with strong antioxidant and antidiabetic properties and to prepare nanoformulations containing this extract. To determine the activities of the extracts prepared from the leaves of the plant, DPPH• and ABTS•+ scavenging, Fe+3 reducing activity, α-amylase, and α-glucosidase inhibition assays were performed. The oleuropein content of the absolute ethanol extract with the highest activity was analysed by HPLC. The characterized extract was loaded into liposomes and chitosan coated liposomes, and the long-term sustainability of their activity was investigated. The encapsulation efficiency was 65.2% for the liposome and 66.8% for the chitosan-coated liposome formulation. The amounts of the extracts released from the formulations were evaluated to exhibit antioxidant and antidiabetic activity.

The effect of 3D printed microfluidic array designs on the preparation of liposome nanoparticles

In this study Digital Light Processing (DLP) was used to manufacture microfluidic arrays with complex geometries for the fabrication of stable liposome nanoparticles. For the purposes of the study three different microfluidic array designs were 3D printed featuring herringbone structures.The effect of the herringbone numbers and the length of the microfluidic channels on the formation of liposomes was investigated by varying the Total Flow Rate (TFR) and the Flow Rate Ratio (FRR). Laser diffraction analysis showed the production of liposomes with reproducible particle sizes and narrow polydispersity index. The obtained particle size was affected by the TFR (3, 5 and 10 ml/min) and FRR (8:2 and 6:4) varying from 40 to 90 nm. However, the number of herringbone structures in the printed microfluidic arrays demonstrated no significant variations on the liposome particle sizes. Stability studies of the formed nanoparticles showed no changes for the 8:2 FRR and small increase of 8–10 nm for the 6:4 respectively. Overall, the study demonstrated the 3D printing capabilities for the printing of complex microfluidic arrays and the successful engineering of liposomes.

Simultaneous quantification of 4-hydroxytamoxifen and hesperidin in liposomal formulations: Development and validation of a RP-HPLC method

Breast cancer treatment options are diverse, with tamoxifen commonly used as a selective estrogen receptor modulator (SERM) for hormone receptor-positive breast cancer. However, tamoxifen can have adverse systemic effects. Local transdermal therapy offers a potential solution by delivering the drug directly to the breast and minimizing systemic exposure. Hesperidin, a flavonoid, exerts synergistic effects when combined with anticancer agents. This combination therapy may be a more effective approach to breast cancer management. Analytical methods have been developed to quantify 4-Hydroxytamoxifen (4-HT) and hesperidin separately; however, no method currently exists for their simultaneous quantification in pharmaceutical formulations. This study aimed to develop and validate a reverse-phase high-performance liquid chromatography (RP-HPLC) method for the simultaneous quantification of 4-HT and hesperidin in liposomal formulations. A Design of Experiments (DoE) approach was employed using a Box-Behnken design (BBD) to optimize the RP-HPLC method. BBD allowed for a reduction in the number of required tests by creating a statistical model to estimate the significance of various factors and interactions. The methanol concentration, flow rate, and injection volume were considered as independent variables for optimization. A mobile phase (90:10 ratio of methanol: 0.1% v/v orthophosphoric acid) with a flow rate of 0.4 mL/min, and an injection volume of 10 μL was selected as optimized chromatographic condition. 4-HT showed a retention time (Rt) of 5.05 min and hesperidin showed an Rt of 7.11 min using an optimized analytical method and was detected at 275 nm. The developed RP-HPLC method was validated according to the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines, confirming its accuracy, precision, linearity, selectivity, and robustness. The validated method was then successfully applied to determine the entrapment efficiency and permeation of 4-HT and hesperidin into loaded liposomes. This study fills a gap in the literature by providing a simple and reliable RP-HPLC method for the simultaneous quantification of 4-HT and hesperidin in liposomal formulations.

Resveratrol-Based Liposomes Improve Cardiac Remodeling Induced by Isoproterenol Partially by Modulating MEF2, Cytochrome C and S100A1 Expression.

Isoproterenol (ISO), a chemically synthesized catecholamine, belongs to β-adrenoceptor agonist used to treat bradycardia. The β-adrenergic agonist is an essential regulator of myocardial metabolism and contractility; however, excessive exposure to ISO can initiate oxidative stress and inflammation. This study aims to investigate the molecular mechanisms underlying ISO-induced cardiac remodeling, the protective efficacy of resveratrol (RSVR), and its liposomal formulation (L-RSVR) against such cardiac change. Wistar albino rats were evenly divided into 4 groups. Control group, ISO group received ISO (50mg/kg, s.c.) twice a week for 2weeks, and RSVR- and L-RSVR-treated groups in which rats received either RSVR or L-RSVR (20mg/kg/day, p.o.) along with ISO for 2weeks. ISO caused a significant elevation of the expression levels of BAX and MEF2 mRNA, S100A1 and cytochrome C proteins, as well as DNA fragmentation in cardiac tissue compared to the control group. Treatment with either RSVR or L-RSVR for 14days significantly ameliorated the damage induced by ISO, as evidenced by the improvement of all measured parameters. The present study shows that L-RSVR provides better cardio-protection against ISO-induced cardiac injury in rats, most likely through modulation of cardiac S100A1 protein expression and inhibition of inflammation and apoptosis.

QbD-assisted optimisation of liposomes in chitosan gel for dermal delivery of aceclofenac as synergistic approach to combat pain and inflammation.

Aceclofenac (ACE) is a drug that was precisely devised to circumvent the shortcomings associated with diclofenac. However, ACE too corresponds to nonsteroidal anti-inflammatory drug (NSAID)-related adverse effects, but with a lower amplitude. The present investigation seeks to develop liposomes loaded with ACE adopting a central composite design (CCD) and formulate a chitosan-based hydrogel for synergistic anti-inflammatory efficacy and improved ACE dermal administration. On the basis of preliminary vesicle size, Poly Dispersity Index (PDI), and drug entrapment, the composition of lipid, cholesterol, and vitamin E TPGS were chosen as independent variables. The formulation composition met the specifications for an optimum liposomal formulation, with total lipid concentration (13.5% w/w), cholesterol concentration (10% w/w), and surfactant concentration (2% w/w). With particle size and PDI of 174.22 ± 5.46nm and 0.285 ± 0.01 respectively, the optimised formulation achieved an entrapment effectiveness of 92.08 ± 3.56%. Based on the CCD design, the optimised formulation Acec-Lipo opt was chosen and was subsequently transformed to a chitosan-based gel formulation for in vitro drug release, penetration through the skin, in vivo analgesic therapeutic activity, and skin irritation testing. % age oedema inhibition was found to be greatest with the Acec-Lipo opt gel formulation, followed by Acec gel. These results reinforce the notion that the inclusion of chitosan resulted in a synergistic effect despite the same strength of the drug. The findings suggested that Acec-Lipo incorporated in chitosan gel for skin targeting might be an effective formulation for topical ACE administration in clinical subjects.

Formulation and characterisation of liposome loaded with shrimp shell chitooligosaccharide‐gallic acid conjugate as influenced by different stabilisers

SummaryEncapsulation efficiency (EE), structure, antioxidant and antimicrobial activities of liposomes loaded with chitooligosaccharide–gallic acid conjugate (COS–GAL) as affected by cholesterol (CHO) and ascorbyl palmitate (AP) as stabilisers were investigated. In addition, release kinetics and in vitro digestion of selected liposomes were also studied. The higher EE was obtained for liposome (AP/COS–GAL) stabilised by 0.50% AP, when used to encapsulate 0.10% COS–GAL conjugate. The highest EE was noticed for 0.25% CHO when used to encapsulate 1.00% conjugate (CHO/COS–GAL) as compared to the counterparts (P &lt; 0.05). Almost similar antioxidant and antimicrobial activities were noticed for all COS–GAL liposomes and COS–GAL powder. Microstructure study suggested the formation of bilayer in liposomes. CHO/COS–GAL showed a lower release efficiency than the AP/COS–GAL. CHO/COS–GAL was also able to protect conjugate during the in vitro digestion. Therefore, liposomes could be used as a promising carrier of COS–GAL conjugate in both foods as well as medical systems.

Impact of Anti-PEG IgM Induced via the Topical Application of a Cosmetic Product Containing PEG Derivatives on the Antitumor Effects of PEGylated Liposomal Antitumor Drug Formulations in Mice.

Poly(ethylene glycol) (PEG) is used in many common products, such as cosmetics. PEG, however, is also used to covalently conjugate drug molecules, proteins, or nanocarriers, which is termed PEGylation, to serve as a shield against the natural immune system of the human body. Repeated administration of some PEGylated products, however, is known to induce anti-PEG antibodies. In addition, preexisting anti-PEG antibodies are now being detected in healthy individuals who have never received PEGylated therapeutics. Both treatment-induced and preexisting anti-PEG antibodies alter the pharmacokinetic properties, which can result in a subsequent reduction in the therapeutic efficacy of administered PEGylated therapeutics through the so-called accelerated blood clearance (ABC) phenomenon. Moreover, these anti-PEG antibodies are widely reported to be related to severe hypersensitivity reactions following the administration of PEGylated therapeutics, including COVID-19 vaccines. We recently reported that the topical application of a cosmetic product containing PEG derivatives induced anti-PEG immunoglobulin M (IgM) in a mouse model. Our finding indicates that the PEG derivatives in cosmetic products could be a major cause of the preexistence of anti-PEG antibodies in healthy individuals. In this study, therefore, the pharmacokinetics and therapeutic effects of Doxil (doxorubicin hydrochloride-loaded PEGylated liposomes) and oxaliplatin-loaded PEGylated liposomes (Liposomal l-OHP) were studied in mice. The anti-PEG IgM antibodies induced by the topical application of cosmetic products obviously accelerated the blood clearance of both PEGylated liposomal formulations. Moreover, in C26 tumor-bearing mice, the tumor growth suppressive effects of both Doxil and Liposomal l-OHP were significantly attenuated in the presence of anti-PEG IgM antibodies induced by the topical application of cosmetic products. These results confirm that the topical application of a cosmetic product containing PEG derivatives could produce preexisting anti-PEG antibodies that then affect the therapeutic efficacy of subsequent doses of PEGylated therapeutics.

Formation of Cell-Sized Liposomes Incorporating a β-Barrel-Structured Porin through Rehydration of a Phospholipid-Membrane Protein Dried Film.

Giant unilamellar vesicles (GUVs) integrated with membrane proteins (proteo-GUVs) are attractive tools for visualizing membrane protein functions such as enzyme reactions and molecular transportation. In the dehydration-rehydration method, one of the methods used to form proteo-GUVs, they are formed by using a dried film containing phospholipids and membrane proteins through rehydration with an alternating current electric field and a supporting gel. However, these methods make it difficult to form proteo-GUVs under physiological salt concentration and charged phospholipid conditions or carry the risk of gel contamination of lipid membranes. Therefore, proteo-GUVs formed by these rehydration methods may be harmful to membrane proteins. Here, we propose a method for the formation of proteo-GUVs containing physiological salt concentrations and negatively charged phospholipids that do not require an electric field and a supporting gel. To investigate the molecular transport of modified outer membrane protein G (OmpG), OmpG-giant unilamellar vesicles (GUVs) and OmpG-large unilamellar vesicles (LUVs) were formed. The structure and function of different mutants reconstituted into LUVs were evaluated by using circular dichroism spectroscopy and electrophysiological measurements. In addition, the molecular transport of OmpG in GUVs was evaluated by monitoring the Ca2+ influx into GUVs and fluorescent molecule leakage from GUVs through OmpG nanopores. We found that the amount of Ca2+ influx into GUVs through the OmpG nanopores depended on the pore size of OmpG. Our method for forming proteo-GUVs can be applied for the functional evaluation of β-barrel porin and in biological sensors using β-barrel porin.

Early Experiences with Intrathecal Administration of Amphotericin B Liposomal Formulation at a Neurosurgical Center.

Intrathecal administration of amphotericin B represents an important adjunctive therapy for management of severe fungal meningitis. Intrathecal preparations have traditionally used amphotericin B deoxycholate. Liposomal amphotericin B is an alternative formulation with good clinical outcomes as systemic therapy, but scant data exist investigating intrathecal use. The aim of this exploratorystudy was to evaluate outcomes following intrathecal administration of liposomal amphotericin B for treatment of severe fungal meningitis. A national shortage of amphotericin B deoxycholate necessitated revision of institutional protocols at a southwestern neurosurgical center in Spring 2023. A starting intrathecal daily dose of 0.125-0.5 mg liposomal amphotericin B was recommended (dependent on insertion device), with 0.125-0.25 mg slow titration every 48 h and up to a 2 mg maximum daily dose. Four cases of fungal meningitis treated with adjunctive intrathecal amphotericin B liposomal formulation were reviewed. This included three cases of coccidioidal meningitis and one case of presumed Fusarium solani meningitis following an outbreak. All patients had initial disease improvement following initiation of intrathecal amphotericin B and were able to tolerate long-term therapy. One coccidioidal meningitis patient expired of neurologic complications shortly after being moved from the intensive care unit (ICU) to a floor unit. All other patients were successfully discharged from the hospital. New headache was the only reported adverse effect, which was managed with dose reduction and did not require therapy discontinuation. Liposomal amphotericin B may be feasibly administered intrathecally for the adjunctive treatment of severe fungal meningitis.