A drift on liposomes to proliposomes: recent advances and promising approaches

Engineering marine phospholipid nanoliposomes via glycerol-infused proliposomes: Mechanisms, strategies, and versatile applications in scalable food-grade nanoliposome production

This study presents a novel approach using polyol-based proliposome to produce marine phospholipids nanoliposomes. Proliposomes were formulated by blending glycerol with phospholipids across varying mass ratios (2:1 to 1:10) at room temperature. Analysis employing polarized light microscopy, FTIR, and DSC revealed that glycerol disrupted the stacked acyl groups within phospholipids, lowering the phase transition temperature (Tm). Krill oil phospholipids (KOP) proliposomes exhibited superior performance in nanoliposomes formation, with a mean diameter of 125.60 ± 3.97 nm, attributed to the decreased Tm (-7.64 and 7.00 °C) compared to soybean phospholipids, along with a correspondingly higher absolute zeta potential (-39.77 ± 1.18 mV). The resulting KOP proliposomes demonstrated liposomes formation stability over six months and under various environmental stresses (dilution, thermal, ionic strength, pH), coupled with in vitro absorption exceeding 90 %. This investigation elucidates the mechanism behind glycerol-formulated proliposomes and proposes innovative strategies for scalable, solvent-free nanoliposome production with implications for functional foods and pharmaceutical applications.

2-Monoacylglycerol Mimetic Liposomes to Promote Intestinal Lymphatic Transport for Improving Oral Bioavailability of Dihydroartemisinin

Purpose

Reducing the first-pass hepatic effect via intestinal lymphatic transport is an effective way to increase the oral absorption of drugs. 2-Monoacylglycerol (2-MAG) as a primary digestive product of dietary lipids triglyceride, can be assembled in chylomicrons and then transported from the intestine into the lymphatic system. Herein, we propose a biomimetic strategy and report a 2-MAG mimetic nanocarrier to target the intestinal lymphatic system via the lipid absorption pathway and improve oral bioavailability.

Methods

The 2-MAG mimetic liposomes were designed by covalently bonding serinol (SER) on the surface of liposomes named SER-LPs to simulate the structure of 2-MAG. Dihydroartemisinin (DHA) was chosen as the model drug because of its disadvantages such as poor solubility and high first-pass effect. The endocytosis and exocytosis mechanisms were investigated in Caco-2 cells and Caco-2 cell monolayers. The capacity of intestinal lymphatic transport was evaluated by ex vivo biodistribution and in vivo pharmacokinetic experiments.

Results

DHA loaded SER-LPs (SER-LPs-DHA) had a particle size of 70 nm and a desirable entrapment efficiency of 93%. SER-LPs showed sustained release for DHA in the simulated gastrointestinal environment. In vitro cell studies demonstrated that the cellular uptake of SER-LPs primarily relied on the caveolae- rather than clathrin-mediated endocytosis pathway and preferred to integrate into the chylomicron assembly process through the endoplasmic reticulum/Golgi apparatus route. After oral administration, SER-LPs efficiently promoted drug accumulation in mesenteric lymphatic nodes. The oral bioavailability of DHA from SER-LPs was 10.40-fold and 1.17-fold larger than that of free DHA and unmodified liposomes at the same dose, respectively.

Conclusion

SER-LPs improved oral bioavailability through efficient intestinal lymphatic transport. These findings of the current study provide a good alternative strategy for oral delivery of drugs with high first-pass hepatic metabolism.

Liposomal propranolol for treatment of infantile hemangioma at compounding pharmacies

Infantile hemangiomas (IH) are common benign soft tissue tumors, frequently affecting infants. While Propranolol Hydrochloride (Pro HCl) has emerged as a promising treatment for IH, its topical application remains challenging due to the need for stable and efficacious carriers. This study investigates the potential of preformulated liposomes as carriers for topical delivery of Pro HCl for the treatment of IH in compounding pharmacies. Liposomes loaded with Pro HCl were prepared using active pharmaceutical ingredient or commercially available propranolol tablets and various dilution media, including Water for Injection (WFI), Dextrose 5%, and NaCl 0.9%. The physicochemical properties of the liposomal formulations (Pro HCl content, encapsulation efficiency, loading capacity, and colloidal stability) were assessed over a 90-day storage at 4 °C. In vitro release kinetics and transdermal permeation of Pro HCl from liposomes were also evaluated. Liposome properties were influenced by the dilution medium. Pro HCl content remained stable in liposomes encapsulating API (Lipo-Pro), regardless of the dilution medium. Lipo-Pro showed sustained drug release over time, suggesting its potential for maintaining therapeutic levels. Pro HCl exhibited enhanced transdermal permeability from Lipo-Pro compared to aqueous solution, indicating its potential for topical IH treatment. Preformulated liposomes offer a stable and effective carrier for Pro HCl, potentially suitable for extemporaneous preparations in compounding pharmacies. Their enhanced transdermal permeability presents a promising alternative for topical IH treatment. This study provides valuable insights into the development of innovative and effective drug delivery strategies for managing IH, with future research focusing on in vivo applications and therapeutic potential.

Lipid-Based Nanotechnology: Liposome

Over the past several decades, liposomes have been extensively developed and used for various clinical applications such as in pharmaceutical, cosmetic, and dietetic fields, due to its versatility, biocompatibility, and biodegradability, as well as the ability to enhance the therapeutic index of free drugs. However, some challenges remain unsolved, including liposome premature leakage, manufacturing irreproducibility, and limited translation success. This article reviews various aspects of liposomes, including its advantages, major compositions, and common preparation techniques, and discusses present U.S. FDA-approved, clinical, and preclinical liposomal nanotherapeutics for treating and preventing a variety of human diseases. In addition, we summarize the significance of and challenges in liposome-enabled nanotherapeutic development and hope it provides the fundamental knowledge and concepts about liposomes and their applications and contributions in contemporary pharmaceutical advancement.

Development of Procathepsin L (pCTS-L)-Inhibiting Lanosterol-Carrying Liposome Nanoparticles to Treat Lethal Sepsis

The pathogenesis of microbial infections and sepsis is partly attributable to dysregulated innate immune responses propagated by late-acting proinflammatory mediators such as procathepsin L (pCTS-L). It was previously not known whether any natural product could inhibit pCTS-L-mediated inflammation or could be strategically developed into a potential sepsis therapy. Here, we report that systemic screening of a NatProduct Collection of 800 natural products led to the identification of a lipophilic sterol, lanosterol (LAN), as a selective inhibitor of pCTS-L-induced production of cytokines [e.g., Tumor Necrosis Factor (TNF) and Interleukin-6 (IL-6)] and chemokines [e.g., Monocyte Chemoattractant Protein-1 (MCP-1) and Epithelial Neutrophil-Activating Peptide (ENA-78)] in innate immune cells. To improve its bioavailability, we generated LAN-carrying liposome nanoparticles and found that these LAN-containing liposomes (LAN-L) similarly inhibited pCTS-L-induced production of several chemokines [e.g., MCP-1, Regulated upon Activation, Normal T Cell Expressed and Presumably Secreted (RANTES) and Macrophage Inflammatory Protein-2 (MIP-2)] in human blood mononuclear cells (PBMCs). In vivo, these LAN-carrying liposomes effectively rescued mice from lethal sepsis even when the first dose was given at 24 h post the onset of this disease. This protection was associated with a significant attenuation of sepsis-induced tissue injury and systemic accumulation of serval surrogate biomarkers [e.g., IL-6, Keratinocyte-derived Chemokine (KC), and Soluble Tumor Necrosis Factor Receptor I (sTNFRI)]. These findings support an exciting possibility to develop liposome nanoparticles carrying anti-inflammatory sterols as potential therapies for human sepsis and other inflammatory diseases.

Temperature-Promoted Giant Unilamellar Vesicle (GUV) Aggregation: A Way of Multicellular Formation

The evolution of unicellular to multicellular life is considered to be an important step in the origin of life, and it is crucial to study the influence of environmental factors on this process through cell models in the laboratory. In this paper, we used giant unilamellar vesicles (GUVs) as a cell model to investigate the relationship between environmental temperature changes and the evolution of unicellular to multicellular life. The zeta potential of GUVs and the conformation of the headgroup of phospholipid molecules at different temperatures were examined using phase analysis light scattering (PALS) and attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), respectively. In addition, the effect of increasing temperature on the aggregation of GUVs was further investigated in ionic solutions, and the possible mechanisms involved were explored. The results showed that increasing temperature reduced the repulsive forces between cells models and promoted their aggregation. This study could effectively contribute to our understanding of the evolution of primitive unicellular to multicellular life.

An extracellular vesicular mutant KRAS-associated protein complex promotes lung inflammation and tumor growth

Extracellular vesicles (EVs) contain more than 100 proteins. Whether there are EVs proteins that act as an 'organiser' of protein networks to generate a new or different biological effect from that identified in EV-producing cells has never been demonstrated. Here, as a proof-of-concept, we demonstrate that EV-G12D-mutant KRAS serves as a leader that forms a protein complex and promotes lung inflammation and tumour growth via the Fn1/IL-17A/FGF21 axis. Mechanistically, in contrast to cytosol derived G12D-mutant KRAS complex from EVs-producing cells, EV-G12D-mutant KRAS interacts with a group of extracellular vesicular factors via fibronectin-1 (Fn1), which drives the activation of the IL-17A/FGF21 inflammation pathway in EV recipient cells. We show that: (i), depletion of EV-Fn1 leads to a reduction of a number of inflammatory cytokines including IL-17A; (ii) induction of IL-17A promotes lung inflammation, which in turn leads to IL-17A mediated induction of FGF21 in the lung; and (iii) EV-G12D-mutant KRAS complex mediated lung inflammation is abrogated in IL-17 receptor KO mice. These findings establish a new concept in EV function with potential implications for novel therapeutic interventions in EV-mediated disease processes.

Monascus Red Pigment Liposomes: Microstructural Characteristics, Stability, and Anticancer Activity

Monascus red pigments (MRPs), which are a kind of natural colorant produced by Monascus spp., are widely used in the food and health supplements industry but are not very stable during processing and storage. Thus, MRPs were embedded into liposome membranes using a thin-film ultrasonic method to improve stability in this study. Monascus red pigments liposomes (MRPL) exhibited spherical unilamellar vesicles (UV) with particle size, polydispersity indexes (PDI), and zeta potential of 20-200 nm, 0.362 ± 0.023, and -42.37 ± 0.21 mV, respectively. pH, thermal, light, metal ion, storage, and in vitro simulated gastrointestinal digestion stability revealed that, compared with free MRPs, liposomes embedding significantly enhanced the stability of MRPs when exposed to adverse environmental conditions. Furthermore, anticancer assay suggested that MRPL exhibited a stronger inhibitory effect on MKN-28 cells by damaging the integrity of cells, with the IC₅₀ value at 0.57 mg/mL. Overall, MRPLs possess stronger stability in external environment and in vitro simulated digestion with greater anticancer activity, indicating that MRPLs have the potential for promising application in the functional foods and pharmaceutical industries.

Glycyrrhetinic acid proliposomes mediated by mannosylated ligand: Preparation, physicochemical characterization, environmental stability and bioactivity evaluation

Glycyrrhetinic acid is a bioactive compound extracted from licorice that exhibits inhibition effect on various cancers. However, its hydrophobicity results in low bioavailability that limits application. We aim to overcome this barrier, the present research was performed to prepare glycyrrhetinic acid proliposomes mediated mannosylated ligand (mannose-diester lauric diacid-cholesterol, MDC) and to evaluate its physicochemical characterizations, environmental stability and bioactivity. In preliminary optimization studies of glycyrrhetinic acid proliposomes mediated MDC (MDC-GA-PL), four optimum operating parameters, cryoprotectant of glucose and mannitol, the mixed cryoprotectant ratio (glucose/mannitol) of 1:1, a cryoprotectant/egg phosphatidylcholine mass ratio of 10/1, and -60 ℃ pre-freezing temperature, were obtained after investigation. Under the optimum lyophilization conditions, MDC-GA-PL was freeze-dried and reconstituted proliposomes were characterized. These proliposomes showed that MDC-GA-PL were well-dispersible spherical particles with an average particle size of 120.80 nm, a polydispersity index about 0.095, a zeta potential of -33.15 mV, encapsulation efficiency of 85.9% and drug loading of 6.38%. In vitro drug release study showed that glycyrrhetinic acid release of MDC-GA-PL conforms to the Higuchi release model. In addition, these proliposomes were stable during six months at 4 ℃. Moreover, acute toxicity assay revealed no substantial safety concern for MDC-GA-PL. Finally, in vitro bioactivity of proliposomes was evaluated. Cytotoxicity effect and apoptosis efficiency of MDC-GA-PL by HepG2 cells was significantly higher than that of glycyrrhetinic acid proliposomes without MDC, demonstrating that MDC has a desirable effect on liver target. Overall, we have reason to believe that MDC-GA-PL would be a promising target delivery to improve therapeutic against hepatic diseases.