Preclinical assessment of nanostructured liquid crystalline particles for the management of bacterial keratitis: in vivo and pharmacokinetics study

Cubosome lipid nanocarriers for delivery of ultra-short antimicrobial peptides

HYPOTHESIS

Although antimicrobial peptides (AMPs) are a promising class of new antibiotics, their inherent susceptibility to degradation requires nanocarrier-mediated delivery. While cubosome nanocarriers have been extensively studied for delivery of AMPs, we do not currently understand why cubosome encapsulation improves antimicrobial efficacy for some compounds but not others. This study therefore aims to investigate the link between the mechanism of action and permeation efficiency of the peptides, their encapsulation efficacy, and the antimicrobial activity of these systems.

EXPERIMENTS

Encapsulation and delivery of Indolicidin, and its ultra-short derivative, Priscilicidin, were investigated using SAXS, cryo-TEM and circular dichroism. Molecular dynamics simulations were used to understand the loading of these peptides within cubosomes. The antimicrobial efficacy was assessed against gram-negative (E. coli) and gram-positive (MRSA) bacteria.

FINDINGS

A high ionic strength solution was required to facilitate high loading of the cationic AMPs, with bilayer encapsulation driven by tryptophan and Fmoc moieties. Cubosome encapsulation did not improve the antimicrobial efficacy of the AMPs consistent with their high permeation, as explained by a recent 'diffusion to capture model'. This suggests that cubosome encapsulation may not be an effective strategy for all antimicrobial compounds, paving the way for improved selection of nanocarriers for AMPs, and other antimicrobial compounds.

Intelligent Drug Delivery: Pioneering Stimuli-Responsive Systems to Revolutionize Disease Management- An In-depth Exploration

In recent years, there has been an escalating interest in stimuli-responsive drug delivery systems (SRDDS) due to their ability to revolutionize the delivery of therapeutics. SRDDSs offer a multitude of benefits in comparison to conventional drug delivery systems (DDS), including spatiotemporal control of drug release, targeted delivery, and improved therapeutic efficacy. The development of various classes of stimuli-responsive DDS, such as pH-responsive, temperature-responsive, photo-responsive, redox responsive systems, has been propelled by advances in materials science, nanotechnology, and biotechnology. These systems exploit specific environmental or physiological cues to trigger drug release in a precisely controlled manner, making them highly promising for the treatment of various diseases. In this review article, an in-depth exploration of the principles, mechanisms, and applications of SRDDS in the context of diverse pathologies such as cancer, arthritis, Alzheimer's disease, atherosclerosis and tissue engineering has been provided. Furthermore, this article delves into the discussion of recent patents, market overview and the progress of research in clinical trials. Overall, this article underscores the transformative potential of SRDDS in enabling personalized, precise, and effective drug delivery for the treatment of the above-mentioned diseases.

Advances in nanomedicine for retinal drug delivery: overcoming barriers and enhancing therapeutic outcomes

Nanomedicine offers a promising avenue for improving retinal drug delivery, effectively addressing challenges associated with ocular diseases like age-related macular degeneration and diabetic retinopathy. Nanoparticles, with their submicron size and customisable surface properties, enable enhanced permeability and retention within retinal tissues, supporting sustained drug release and minimising systemic side effects. Nanostructured scaffolds further provide a supportive environment for retinal cell growth and tissue regeneration, crucial for treating degenerative conditions. Additionally, advanced nanodevices facilitate real-time monitoring and controlled drug release, marking significant progress in retinal therapy. This study reviews recent advancements in nanomedicine for retinal drug delivery, critically analysing design innovations, therapeutic benefits, and limitations of these systems. By advancing nanotechnology integration in ocular therapies, this field holds strong potential for overcoming current barriers, ultimately improving patient outcomes and quality of life.

Recent Advances in Ocular Drug Delivery: Insights into Lyotropic Liquid Crystals

Background/Objectives: This review examines the evolution of lyotropic liquid crystals (LLCs) in ocular drug delivery, focusing on their ability to address the challenges associated with traditional ophthalmic formulations. This study aims to underscore the enhanced bioavailability, prolonged retention, and controlled release properties of LLCs that significantly improve therapeutic outcomes. Methods: This review synthesizes data from various studies on both bulk-forming LLCs and liquid crystal nanoparticles (LCNPs). It also considers advanced analytical techniques, including the use of machine learning and AI-driven predictive modeling, to forecast the phase behavior and molecular structuring of LLC systems. Emerging technologies in biosensing and real-time diagnostics are discussed to illustrate the broader applicability of LLCs in ocular health. Results: LLCs are identified as pivotal in promoting targeted drug delivery across different regions of the eye, with specific emphasis on the tailored optimization of LCNPs. This review highlights principal categories of LLCs used in ocular applications, each facilitating unique interactions with physiological systems to enhance drug efficacy and safety. Additionally, novel applications in biosensing demonstrate LLCs' capacity to improve diagnostic processes. Conclusions: Lyotropic liquid crystals offer transformative potential in ocular drug delivery by overcoming significant limitations of conventional delivery methods. The integration of predictive technologies and biosensing applications further enriches the utility of LLCs, indicating a promising future for their use in clinical settings. This review points to continued advancements and encourages further research in LLC technology to maximize its therapeutic benefits.

Recent advances in nanostructured delivery systems for vancomycin

Despite the development of new generations of antibiotics, vancomycin remained as a high-efficacy antibiotic for treating the infections caused by MRSA. Researchers have explored various nanoformulations, aiming to enhance the therapeutic efficacy of vancomycin. Such novel formulations improve the effectiveness of drug cargoes in treating bacterial infections and minimizing the risk of adverse effects. The vast of researches have focuses on enhancing the permeation ability of vancomycin through different biological barriers especially those of gastrointestinal tract. Increasing the drug loading and tuning the drug release from nanocarrier are other important goal for many conducted studies. This study reviews the newest nano-based formulations for vancomycin as a key antibiotic in treating hospitalized bacterial infections.

Fostering the unleashing potential of nanocarriers-mediated delivery of ocular therapeutics

Ocular delivery is the most challenging aspect in the field of pharmaceutical research. The major hurdle for the controlled delivery of drugs to the eye includes the physiological static barriers such as the complex layers of the cornea, sclera and retina which restrict the drug from permeating into the anterior and posterior segments of the eye. Recent years have witnessed inventions in the field of conventional and nanocarrier drug delivery which have shown considerable enhancement in delivering small to large molecules across the eye. The dynamic challenges associated with conventional systems include limited drug contact time and inadequate ocular bioavailability resulting from solution drainage, tear turnover, and dilution or lacrimation. To this end, various bioactive-based nanosized carriers including liposomes, ethosomes, niosomes, dendrimer, nanogel, nanofibers, contact lenses, nanoprobes, selenium nanobells, nanosponge, polymeric micelles, silver nanoparticles, and gold nanoparticles among others have been developed to circumvent the limitations associated with the conventional dosage forms. These nanocarriers have been shown to achieve enhanced drug permeation or retention and prolong drug release in the ocular tissue due to their better tissue adherence. The surface charge and the size of nanocarriers (10-1000 nm) are the important key factors to overcome ocular barriers. Various nanocarriers have been shown to deliver active therapeutic molecules including timolol maleate, ampicillin, natamycin, voriconazole, cyclosporine A, dexamethasone, moxifloxacin, and fluconazole among others for the treatment of anterior and posterior eye diseases. Taken together, in a nutshell, this extensive review provides a comprehensive perspective on the numerous facets of ocular drug delivery with a special focus on bioactive nanocarrier-based approaches, including the difficulties and constraints involved in the fabrication of nanocarriers. This also provides the detailed invention, applications, biodistribution and safety-toxicity of nanocarriers-based therapeutcis for the ophthalmic delivery.

Recent Advances in the Development of Liquid Crystalline Nanoparticles as Drug Delivery Systems

Due to their distinctive structural features, lyotropic nonlamellar liquid crystalline nanoparticles (LCNPs), such as cubosomes and hexosomes, are considered effective drug delivery systems. Cubosomes have a lipid bilayer that makes a membrane lattice with two water channels that are intertwined. Hexosomes are inverse hexagonal phases made of an infinite number of hexagonal lattices that are tightly connected with water channels. These nanostructures are often stabilized by surfactants. The structure's membrane has a much larger surface area than that of other lipid nanoparticles, which makes it possible to load therapeutic molecules. In addition, the composition of mesophases can be modified by pore diameters, thus influencing drug release. Much research has been conducted in recent years to improve their preparation and characterization, as well as to control drug release and improve the efficacy of loaded bioactive chemicals. This article reviews current advances in LCNP technology that permit their application, as well as design ideas for revolutionary biomedical applications. Furthermore, we have provided a summary of the application of LCNPs based on the administration routes, including the pharmacokinetic modulation property.

Liquid crystalline nanoparticles enable a multifunctional approach for topical psoriasis therapy by co-delivering triptolide and siRNAs

Liquid crystalline nanoparticles (LCNs) are an attractive drugs topical delivery system due to the great internal ordering, wide interfacial area and structural similarities with the skin. In this work, LCNs were designed to encapsulate triptolide (TP) and to complex on its surface small interfering RNAs (siRNA) targeting TNF-α and IL-6, aiming at topical co-delivery and regulating multi-targets in psoriasis. These multifunctional LCNs showed appropriate physicochemical properties for topical application, such as a mean size of 150 nm, low polydispersion, TP encapsulation greater than 90% and efficient complexation with siRNA. The internal reverse hexagonal mesostructure of LCNs was confirmed by SAXS while their morphology was assessed by cryo-TEM. In vitro permeation studies revealed an increase of more than 20-fold in the distribution of TP through the porcine epidermis/dermis was achieved after the application of LCN-TP or LCN TP in hydrogel. In cell culture, LCNs showed good compatibility and rapid internalization, which was attributed to macropinocytosis and caveolin-mediated endocytosis. Anti-inflammatory potential of multifunctional LCNs was assessed by reducing of TNF-α, IL-6, IL-1β and TGF-β1 levels in LPS-stimulated macrophages. These results support the hypothesis that the co-delivery of TP and siRNAs by LCNs may be a new strategy for psoriasis topical therapy.